Legacy effects of nitrogen and phosphorus additions on vegetation and carbon stocks of upland heaths
Paassen, José G. van; Britton, Andrea J. ; Mitchell, Ruth J. ; Street, Lorna E. ; Johnson, David ; Coupar, Andrew ; Woodin, Sarah J. - \ 2020
New Phytologist (2020). - ISSN 0028-646X
long term - nitrogen deposition - nutrient cycling - soil - upland heath - vegetation
Soil carbon (C) pools and plant community composition are regulated by nitrogen (N) and phosphorus (P) availability. Atmospheric N deposition impacts ecosystem C storage, but the direction of response varies between systems. Phosphorus limitation may constrain C storage response to N, hence P application to increase plant productivity and thus C sequestration has been suggested. We revisited a 23-yr-old field experiment where N and P had been applied to upland heath, a widespread habitat supporting large soil C stocks. At 10 yr after the last nutrient application we quantified long-term changes in vegetation composition and in soil and vegetation C and P stocks. Nitrogen addition, particularly when combined with P, strongly influenced vegetation composition, favouring grasses over Calluna vulgaris, and led to a reduction in vegetation C stocks. However, soil C stocks did not respond to nutrient treatments. We found 40% of the added P had accumulated in the soil. This study showed persistent effects of N and N + P on vegetation composition, whereas effects of P alone were small and showed recovery. We found no indication that P application could mitigate the effects of N on vegetation or increase C sequestration in this system.
Colonies of the fungus Aspergillus niger are highly differentiated to adapt to local carbon source variation
Daly, Paul ; Peng, Mao ; Mitchell, Hugh D. ; Kim, Young Mo ; Ansong, Charles ; Brewer, Heather ; Gijsel, Peter de; Lipton, Mary S. ; Markillie, Lye Meng ; Nicora, Carrie D. ; Orr, Galya ; Wiebenga, Ad ; Hildén, Kristiina S. ; Kabel, Mirjam A. ; Baker, Scott E. ; Mäkelä, Miia R. ; Vries, Ronald P. de - \ 2020
Environmental Microbiology 22 (2020)3. - ISSN 1462-2912 - p. 1154 - 1166.
Saprobic fungi, such as Aspergillus niger, grow as colonies consisting of a network of branching and fusing hyphae that are often considered to be relatively uniform entities in which nutrients can freely move through the hyphae. In nature, different parts of a colony are often exposed to different nutrients. We have investigated, using a multi-omics approach, adaptation of A. niger colonies to spatially separated and compositionally different plant biomass substrates. This demonstrated a high level of intra-colony differentiation, which closely matched the locally available substrate. The part of the colony exposed to pectin-rich sugar beet pulp and to xylan-rich wheat bran showed high pectinolytic and high xylanolytic transcript and protein levels respectively. This study therefore exemplifies the high ability of fungal colonies to differentiate and adapt to local conditions, ensuring efficient use of the available nutrients, rather than maintaining a uniform physiology throughout the colony.
A review on yolk sac utilization in poultry
Wagt, Ilonka van der; Jong, I.C. de; Mitchell, M.A. ; Molenaar, R. ; Brand, H. van den - \ 2020
Poultry Science 99 (2020)4. - ISSN 0032-5791 - p. 2162 - 2175.
During incubation, embryonic growth and development are dependent on nutrients deposited in the egg. The content of the yolk can be transferred to the embryo in 2 ways: directly into the intestine via the yolk stalk or through the highly vascularized yolk sac membrane. It has been suggested that, as a result of genetic selection and improved management, the increase in posthatch growth rate and concurrently the increase in metabolic rate of broiler chickens during the last 50 yr has also increased embryonic metabolism. A higher metabolic rate during incubation would imply a lower residual yolk weight and possibly lower energy reserve for the hatchling. This might affect posthatch development and performance. This review examined scientific publications published between 1930 and 2018 to compare residual yolk weight at hatch, metabolic heat production, and yolk utilization throughout incubation. This review aimed to investigate 1) whether or not residual yolk weight and composition has been changed during the 88-yr period considered and 2) which abiotic and biotic factors affect yolk utilization in poultry during incubation and the early posthatch period. It can be concluded that 1) residual yolk weight and the total solid amount of the residual yolk at hatch seem to be decreased in the recent decades. It cannot be concluded whether the (lack of) differences between old and modern strains are due to genetic selection, changed management and incubation conditions, or moment of sampling (immediately after hatch or at pulling). It is remarkable that with the genetic progress and improved management and incubation conditions over the last 88 yr, effects on yolk utilization efficiency and embryonic metabolic heat production are limited; 2) factors specially affecting residual yolk weight at hatch include egg size and incubation temperature, whereas breeder age has more influence on nutrient composition of the residual yolk.
Experimental translocations to low predation lead to non-parallel increases in relative brain size
Mitchell, David J. ; Vega-Trejo, Regina ; Kotrschal, Alexander - \ 2020
Biology Letters 16 (2020)1. - ISSN 1744-9561 - 1 p.
cognition - convergent evolution - predator–prey interactions - telencephalon
Predation is a near ubiquitous factor of nature and a powerful selective force on prey. Moreover, it has recently emerged as an important driver in the evolution of brain anatomy, though population comparisons show ambiguous results with considerable unexplained variation. Here, we test the reproducibility of reduced predation on evolutionary trajectories of brain evolution. We make use of an introduction experiment, whereby guppies (Poecilia reticulata) from a single high predation stream were introduced to four low predation streams. After 8-9 years of natural selection in the wild and two generations of common garden conditions in the laboratory, we quantified brain anatomy. Relative brain region sizes did not differ between populations. However, we found a general increase and striking variation in relative brain size of introduced populations, which varied from no change to a 12.5% increase in relative brain weight, relative to the ancestral high predation population. We interpret this as evidence for non-parallel evolution, which implies a weak or inconsistent association of relative brain size with fitness in low predation sites. The evolution of brain anatomy appears sensitive to unknown environmental factors, or contingent on either chance events or historical legacies of environmental change.
Global, regional, and national burden of neurological disorders, 1990–2016: a systematic analysis for the Global Burden of Disease Study 2016
Feigin, Valery L. ; Nichols, Emma ; Alam, Tahiya ; Bannick, Marlena S. ; Beghi, Ettore ; Blake, Natacha ; Culpepper, William J. ; Dorsey, E.R. ; Elbaz, Alexis ; Ellenbogen, Richard G. ; Fisher, James L. ; Fitzmaurice, Christina ; Giussani, Giorgia ; Glennie, Linda ; James, Spencer L. ; Johnson, Catherine Owens ; Kassebaum, Nicholas J. ; Logroscino, Giancarlo ; Marin, Benoît ; Mountjoy-Venning, W.C. ; Nguyen, Minh ; Ofori-Asenso, Richard ; Patel, Anoop P. ; Piccininni, Marco ; Roth, Gregory A. ; Steiner, Timothy J. ; Stovner, Lars Jacob ; Szoeke, Cassandra E.I. ; Theadom, Alice ; Vollset, Stein Emil ; Wallin, Mitchell Taylor ; Wright, Claire ; Zunt, Joseph Raymond ; Abbasi, Nooshin ; Abd-Allah, Foad ; Abdelalim, Ahmed ; Abdollahpour, Ibrahim ; Aboyans, Victor ; Abraha, Haftom Niguse ; Acharya, Dilaram ; Adamu, Abdu A. ; Adebayo, Oladimeji M. ; Adeoye, Abiodun Moshood ; Adsuar, Jose C. ; Afarideh, Mohsen ; Agrawal, Sutapa ; Ahmadi, Alireza ; Ahmed, Muktar Beshir ; Aichour, Amani Nidhal ; Geleijnse, Johanna M. - \ 2019
The Lancet Neurology 18 (2019)5. - ISSN 1474-4422 - p. 459 - 480.
Background: Neurological disorders are increasingly recognised as major causes of death and disability worldwide. The aim of this analysis from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2016 is to provide the most comprehensive and up-to-date estimates of the global, regional, and national burden from neurological disorders. Methods: We estimated prevalence, incidence, deaths, and disability-adjusted life-years (DALYs; the sum of years of life lost [YLLs] and years lived with disability [YLDs]) by age and sex for 15 neurological disorder categories (tetanus, meningitis, encephalitis, stroke, brain and other CNS cancers, traumatic brain injury, spinal cord injury, Alzheimer's disease and other dementias, Parkinson's disease, multiple sclerosis, motor neuron diseases, idiopathic epilepsy, migraine, tension-type headache, and a residual category for other less common neurological disorders) in 195 countries from 1990 to 2016. DisMod-MR 2.1, a Bayesian meta-regression tool, was the main method of estimation of prevalence and incidence, and the Cause of Death Ensemble model (CODEm) was used for mortality estimation. We quantified the contribution of 84 risks and combinations of risk to the disease estimates for the 15 neurological disorder categories using the GBD comparative risk assessment approach. Findings: Globally, in 2016, neurological disorders were the leading cause of DALYs (276 million [95% UI 247–308]) and second leading cause of deaths (9·0 million [8·8–9·4]). The absolute number of deaths and DALYs from all neurological disorders combined increased (deaths by 39% [34–44] and DALYs by 15% [9–21]) whereas their age-standardised rates decreased (deaths by 28% [26–30] and DALYs by 27% [24–31]) between 1990 and 2016. The only neurological disorders that had a decrease in rates and absolute numbers of deaths and DALYs were tetanus, meningitis, and encephalitis. The four largest contributors of neurological DALYs were stroke (42·2% [38·6–46·1]), migraine (16·3% [11·7–20·8]), Alzheimer's and other dementias (10·4% [9·0–12·1]), and meningitis (7·9% [6·6–10·4]). For the combined neurological disorders, age-standardised DALY rates were significantly higher in males than in females (male-to-female ratio 1·12 [1·05–1·20]), but migraine, multiple sclerosis, and tension-type headache were more common and caused more burden in females, with male-to-female ratios of less than 0·7. The 84 risks quantified in GBD explain less than 10% of neurological disorder DALY burdens, except stroke, for which 88·8% (86·5–90·9) of DALYs are attributable to risk factors, and to a lesser extent Alzheimer's disease and other dementias (22·3% [11·8–35·1] of DALYs are risk attributable) and idiopathic epilepsy (14·1% [10·8–17·5] of DALYs are risk attributable). Interpretation: Globally, the burden of neurological disorders, as measured by the absolute number of DALYs, continues to increase. As populations are growing and ageing, and the prevalence of major disabling neurological disorders steeply increases with age, governments will face increasing demand for treatment, rehabilitation, and support services for neurological disorders. The scarcity of established modifiable risks for most of the neurological burden demonstrates that new knowledge is required to develop effective prevention and treatment strategies. Funding: Bill & Melinda Gates Foundation.
The Cultural and Spiritual Significance of Nature in the Management and Governance of Protected Areas and World Heritage Sites
Bernbaum, E. ; Verschuuren, B. - \ 2019
In: Proceedings of the 2018 US/ICOMOS Symposium. - San Francisco : US/ICOMOS - 18 p.
This paper chronicles the evolution of the IUCN Specialist Group on the Cultural and Spiritual Values of Protected Areas (CSVPA) with a focus on the development of its current Cultural and Spiritual Nature Program, which includes IUCN Best Practices Guidelines, a peer-reviewed book, training modules, case studies, and a network -- all dedicated to promoting and integrating the cultural and spiritual significance of nature in the management and governance of protected and conserved areas. The program is being developed in conjunction with the IUCN ICOMOS Nature Culture and Culture Nature Journeys and seeks to create a comprehensive approach to the conservation of natural and cultural heritage. Six principles distilled from the input of 200 international experts and reviewers through editorial work and workshops at the World Parks Congress in Australia, the World Conservation Congress in Hawai’i, and the Isle of Vilm in Germany provide key insights and lessons learned. The paper concludes with next steps for implementing the Best Practice Guidelines through the development of training modules and workshops and a network for providing support and sharing experiences.
|The Role of Visualization in Controversies over Technological Developments
Gommeh, E. ; Metze, T.A.P. ; Dijstelbloem, Huub - \ 2019
Societal controversies over technological development, among them food technologies, often have a visual dimension. For example, an image of flammable tap water (originally from the documentary Gasland) strengthened the association of a contested technology – hydraulic fracturing – with risk and influenced the evolution of the controversy in some countries (Mazur 2016; Metze 2017). Yet, visualizations in controversies over technological developments are often overlooked. To better understand the role of visualization in these controversies we develop the Visual Discourse Coalitions approach by drawing on work on discourse coalitions (Bulkeley, 2000; Dodge & Lee, 2017; Hajer, 1995), the Dynamic Discourse Coalitions approach (Metze & Dodge, 2016) and visual political theory (Bleiker 2018; Mitchell 1994). In this paper we conceptualize ‘Visual Discourse Coalition’ (VDC), a network of actors who share a similar storyline and similar visual representations of the issue at hand, and develop the ‘VDC theoretical framework’ which approaches visualization as a practice that contributes to the evolution of discourse coalitions. We explore a method to identify VDC’s in controversies over technological developments and to reveal manners in which visualization contributes to discourse coalitions evolution. The goal of our research is to reveal how actors use visualization and influence the dynamics of the controversy. Drawing on empirical examples from the shale gas case we reveal four ways in which visualization influences discourse coalitions: (1) visualization repeats and strengthens storylines of discourse coalitions, (2) visualization connects storyline of different discourse coalitions, (3) visualization contributes to breaking apart of a discourse coalition into different ways of interpreting a policy issue, and (4) visualization emphasizes and increases the tension between storylines of different discourse coalitions. We suggest that the VDC theoretical and methodological frameworks can be applied to controversies over food technologies. They can highlight special features of visualizations and a unique way in which they influence the controversy. Moreover, the visual dimension of a controversy can expose new aspects of the controversy, and in some cases can result in an emergence of new actors in it. Thus, it is important for decision makers to acknowledge the visual dimension of a controversy and to study it.
A global synthesis reveals biodiversity-mediated benefits for crop production
Dainese, Matteo ; Martin, Emily A. ; Aizen, Marcelo A. ; Albrecht, Matthias ; Bartomeus, Ignasi ; Bommarco, Riccardo ; Carvalheiro, Luisa G. ; Chaplin-Kramer, Rebecca ; Gagic, Vesna ; Garibaldi, Lucas A. ; Ghazoul, Jaboury ; Grab, Heather ; Jonsson, Mattias ; Karp, Daniel S. ; Kennedy, Christina M. ; Kleijn, David ; Kremen, Claire ; Landis, Douglas A. ; Letourneau, Deborah K. ; Marini, Lorenzo ; Poveda, Katja ; Rader, Romina ; Smith, Henrik G. ; Tscharntke, Teja ; Andersson, Georg K.S. ; Badenhausser, Isabelle ; Baensch, Svenja ; Bezerra, Antonio D.M. ; Bianchi, Felix J.J.A. ; Boreux, Virginie ; Bretagnolle, Vincent ; Caballero-Lopez, Berta ; Cavigliasso, Pablo ; Ćetković, Aleksandar ; Chacoff, Natacha P. ; Classen, Alice ; Cusser, Sarah ; Silva E Silva, Felipe D. Da; Groot, G.A. de; Dudenhöffer, Jan H. ; Ekroos, Johan ; Fijen, Thijs ; Franck, Pierre ; Freitas, Breno M. ; Garratt, Michael P.D. ; Gratton, Claudio ; Hipólito, Juliana ; Holzschuh, Andrea ; Hunt, Lauren ; Iverson, Aaron L. ; Jha, Shalene ; Keasar, Tamar ; Kim, Tania N. ; Kishinevsky, Miriam ; Klatt, Björn K. ; Klein, Alexandra Maria ; Krewenka, Kristin M. ; Krishnan, Smitha ; Larsen, Ashley E. ; Lavigne, Claire ; Liere, Heidi ; Maas, Bea ; Mallinger, Rachel E. ; Pachon, Eliana Martinez ; Martínez-Salinas, Alejandra ; Meehan, Timothy D. ; Mitchell, Matthew G.E. ; Molina, Gonzalo A.R. ; Nesper, Maike ; Nilsson, Lovisa ; O'Rourke, Megan E. ; Peters, Marcell K. ; Plećaš, Milan ; Potts, Simon G. ; L. Ramos, Davi de; Rosenheim, Jay A. ; Rundlöf, Maj ; Rusch, Adrien ; Sáez, Agustín ; Scheper, Jeroen ; Schleuning, Matthias ; Schmack, Julia M. ; Sciligo, Amber R. ; Seymour, Colleen ; Stanley, Dara A. ; Stewart, Rebecca ; Stout, Jane C. ; Sutter, Louis ; Takada, Mayura B. ; Taki, Hisatomo ; Tamburini, Giovanni ; Tschumi, Matthias ; Viana, Blandina F. ; Westphal, Catrin ; Willcox, Bryony K. ; Wratten, Stephen D. ; Yoshioka, Akira ; Zaragoza-Trello, Carlos ; Zhang, Wei ; Zou, Yi ; Steffan-Dewenter, Ingolf - \ 2019
Science Advances 5 (2019)10. - ISSN 2375-2548
Human land use threatens global biodiversity and compromises multiple ecosystem functions critical to food production. Whether crop yield-related ecosystem services can be maintained by a few dominant species or rely on high richness remains unclear. Using a global database from 89 studies (with 1475 locations), we partition the relative importance of species richness, abundance, and dominance for pollination; biological pest control; and final yields in the context of ongoing land-use change. Pollinator and enemy richness directly supported ecosystem services in addition to and independent of abundance and dominance. Up to 50% of the negative effects of landscape simplification on ecosystem services was due to richness losses of service-providing organisms, with negative consequences for crop yields. Maintaining the biodiversity of ecosystem service providers is therefore vital to sustain the flow of key agroecosystem benefits to society.
Elucidating transmission patterns of endemic Mycobacterium avium subsp. paratuberculosis using molecular epidemiology
Mitchell, Rebecca M. ; Beaver, Annabelle ; Knupfer, Elena ; Pradhan, Abani K. ; Fyock, Terry ; Whitlock, Robert H. ; Schukken, Ynte H. - \ 2019
Veterinary Sciences 6 (2019)1. - ISSN 2306-7381
MLSSR typing - Mutation rate - Mycobacterial co-infections - Mycobacterium avium subsp. paratuberculosis (MAP) - Vertical transmission - Within-host evolution
Mycobacterial diseases are persistent and characterized by lengthy latent periods. Thus, epidemiological models require careful delineation of transmission routes. Understanding transmission routes will improve the quality and success of control programs. We aimed to study the infection dynamics of Mycobacterium avium subsp. paratuberculosis (MAP), the causal agent of ruminant Johne's disease, and to distinguish within-host mutation from individual transmission events in a longitudinally MAP-defined dairy herd in upstate New York. To this end, semi-annual fecal samples were obtained from a single dairy herd over the course of seven years, in addition to tissue samples from a selection of culled animals. All samples were cultured for MAP, and multi-locus short-sequence repeat (MLSSR) typing was used to determine MAP SSR types. We concluded from these precise MAP infection data that, when the tissue burden remains low, the majority of MAP infections are not detectable by routine fecal culture but will be identified when tissue culture is performed after slaughter. Additionally, we determined that in this herd vertical infection played only a minor role in MAP transmission. By means of extensive and precise longitudinal data from a single dairy herd, we have come to new insights regarding MAP co-infections and within-host evolution.
Nature and mental health: An ecosystem service perspective
Bratman, Gregory N. ; Anderson, Christopher B. ; Berman, Marc G. ; Cochran, Bobby ; Vries, Sjerp De; Flanders, Jon ; Folke, Carl ; Frumkin, Howard ; Gross, James J. ; Hartig, Terry ; Kahn, Peter H. ; Kuo, Ming ; Lawler, Joshua J. ; Levin, Phillip S. ; Lindahl, Therese ; Meyer-lindenberg, Andreas ; Mitchell, Richard ; Ouyang, Zhiyun ; Roe, Jenny ; Scarlett, Lynn ; Smith, Jeffrey R. ; Bosch, Matilda Van Den; Wheeler, Benedict W. ; White, Mathew P. ; Zheng, Hua ; Daily, Gretchen C. - \ 2019
Science Advances 5 (2019)7. - ISSN 2375-2548 - 15 p.
A growing body of empirical evidence is revealing the value of nature experience for mental health. With rapid urbanization and declines in human contact with nature globally, crucial decisions must be made about how to preserve and enhance opportunities for nature experience. Here, we first provide points of consensus across the natural, social, and health sciences on the impacts of nature experience on cognitive functioning, emotional well-being, and other dimensions of mental health. We then show how ecosystem service assessments can be expanded to include mental health, and provide a heuristic, conceptual model for doing so.
Improving scientific advice for the conservation and management of oceanic sharks and rays : Final report - Study
Coelho, R. ; Apostolaki, P. ; Bach, P. ; Brunel, T.P.A. ; Davies, T. ; Diez, G. ; Ellis, J. ; Escalle, L. ; Lopez, J. ; Merino, Gorka ; Mitchell, R. ; Macias, D. ; Murua, H. ; Overzee, H.M.J. van; Poos, J.J. ; Richardson, H. ; Rosa, D. ; Sanchez, S. ; Santos, C. ; Seret, B. ; Urbina, J.O. ; Walker, N. - \ 2019
Brussels : European Commission - ISBN 9789292024550 - 658 p.
The purpose of this specific study is to provide the Directorate-General for Maritime Affairs and Fisheries (DG MARE) with: Updated information regarding the association or occurrence of pelagic sharks and rays in different fisheries; Updated information regarding data collection and methodological approaches for the assessment of conservation status of sharks; A critical review of existing Conservation and Management Measures (CMMs) for sharks and of the current conservation status of the species concerned; and Proposals to improve and/or provide alternative options for conservation and management of sharks taking into account any recent methodological advances and new data or information. The species of interest are the main pelagic sharks caught by pelagic fisheries, including under Sustainable Fisheries Partnership Agreements (longline and purse seine fisheries). The study also considers some pelagic elasmobranchs included in Article 13 (species prohibitions) of the Council Regulation 2016/72 fixing for 2016 the fishing opportunities for certain fish stocks. The main regions focused are the oceanic regions covered by tuna-RFMOs where those species of elasmobranch are represented in the catches, specifically the Atlantic (ICCAT region), the Indian Ocean (IOTC region) and the Pacific (WCPFC and IATTC regions)
Disentangling the genetics of lean mass
Karasik, David ; Zillikens, M.C. ; Hsu, Yi Hsiang ; Aghdassi, Ali ; Akesson, Kristina ; Amin, Najaf ; Barroso, Inês ; Bennett, David A. ; Bertram, Lars ; Bochud, Murielle ; Borecki, Ingrid B. ; Broer, Linda ; Buchman, Aron S. ; Byberg, Liisa ; Campbell, Harry ; Campos-Obando, Natalia ; Cauley, Jane A. ; Cawthon, Peggy M. ; Chambers, John C. ; Chen, Zhao ; Cho, Nam H. ; Choi, Hyung Jin ; Chou, Wen Chi ; Cummings, Steven R. ; Groot, Lisette C.P.G.M. De; Jager, Phillip L. De; Demuth, Ilja ; Diatchenko, Luda ; Econs, Michael J. ; Eiriksdottir, Gudny ; Enneman, Anke W. ; Eriksson, Joel ; Eriksson, Johan G. ; Estrada, Karol ; Evans, Daniel S. ; Feitosa, Mary F. ; Fu, Mao ; Gieger, Christian ; Grallert, Harald ; Gudnason, Vilmundur ; Lenore, Launer J. ; Hayward, Caroline ; Hofman, Albert ; Homuth, Georg ; Huffman, Kim M. ; Husted, Lise B. ; Illig, Thomas ; Ingelsson, Erik ; Ittermann, Till ; Jansson, John Olov ; Johnson, Toby ; Biffar, Reiner ; Jordan, Joanne M. ; Jula, Antti ; Karlsson, Magnus ; Khaw, Kay Tee ; Kilpeläinen, Tuomas O. ; Klopp, Norman ; Kloth, Jacqueline S.L. ; Koller, Daniel L. ; Kooner, Jaspal S. ; Kraus, William E. ; Kritchevsky, Stephen ; Kutalik, Zoltán ; Kuulasmaa, Teemu ; Kuusisto, Johanna ; Laakso, Markku ; Lahti, Jari ; Lang, Thomas ; Langdahl, Bente L. ; Lerch, Markus M. ; Lewis, Joshua R. ; Lill, Christina ; Lind, Lars ; Lindgren, Cecilia ; Liu, Yongmei ; Livshits, Gregory ; Ljunggren, Östen ; Loos, Ruth J.F. ; Lorentzon, Mattias ; Luan, Jian An ; Luben, Robert N. ; Malkin, Ida ; McGuigan, Fiona E. ; Medina-Gomez, Carolina ; Meitinger, Thomas ; Melhus, Håkan ; Mellström, Dan ; Michaëlsson, Karl ; Mitchell, Braxton D. ; Morris, Andrew P. ; Mosekilde, Leif ; Nethander, Maria ; Newman, Anne B. ; Oconnell, Jeffery R. ; Oostra, Ben A. ; Orwoll, Eric S. ; Palotie, Aarno ; Peacock, Munro ; Perola, Markus ; Peters, Annette ; Prince, Richard L. ; Psaty, Bruce M. ; Räikkönen, Katri ; Ralston, Stuart H. ; Ripatti, Samuli ; Rivadeneira, Fernando ; Robbins, John A. ; Rotter, Jerome I. ; Rudan, Igor ; Salomaa, Veikko ; Satterfield, Suzanne ; Schipf, Sabine ; Shin, Chan Soo ; Smith, Albert V. ; Smith, Shad B. ; Soranzo, Nicole ; Spector, Timothy D. ; StanÄ Áková, Alena ; Stefansson, Kari ; Steinhagen-Thiessen, Elisabeth ; Stolk, Lisette ; Streeten, Elizabeth A. ; Styrkarsdottir, Unnur ; Swart, Karin M.A. ; Thompson, Patricia ; Thomson, Cynthia A. ; Thorleifsson, Gudmar ; Thorsteinsdottir, Unnur ; Tikkanen, Emmi ; Tranah, Gregory J. ; Uitterlinden, André G. ; Duijn, Cornelia M. Van; Schoor, Natasja M. Van; Vandenput, Liesbeth ; Vollenweider, Peter ; Völzke, Henry ; Wactawski-Wende, Jean ; Walker, Mark ; J Wareham, Nicholas ; Waterworth, Dawn ; Weedon, Michael N. ; Wichmann, H.E. ; Widen, Elisabeth ; Williams, Frances M.K. ; Wilson, James F. ; Wright, Nicole C. ; Yerges-Armstrong, Laura M. ; Yu, Lei ; Zhang, Weihua ; Zhao, Jing Hua ; Zhou, Yanhua ; Nielson, Carrie M. ; Harris, Tamara B. ; Demissie, Serkalem ; Kiel, Douglas P. ; Ohlsson, Claes - \ 2019
American Journal of Clinical Nutrition 109 (2019)2. - ISSN 0002-9165 - p. 276 - 278.
body composition - body fat - meta-Analysis of genome-wide association studies - metabolic profile - skeletal muscle
Background Lean body mass (LM) plays an important role in mobility and metabolic function. We previously identified five loci associated with LM adjusted for fat mass in kilograms. Such an adjustment may reduce the power to identify genetic signals having an association with both lean mass and fat mass. Objectives To determine the impact of different fat mass adjustments on genetic architecture of LM and identify additional LM loci. Methods We performed genome-wide association analyses for whole-body LM (20 cohorts of European ancestry with n = 38,292) measured using dual-energy X-ray absorptiometry) or bioelectrical impedance analysis, adjusted for sex, age, age 2, and height with or without fat mass adjustments (Model 1 no fat adjustment; Model 2 adjustment for fat mass as a percentage of body mass; Model 3 adjustment for fat mass in kilograms). Results Seven single-nucleotide polymorphisms (SNPs) in separate loci, including one novel LM locus (TNRC6B), were successfully replicated in an additional 47,227 individuals from 29 cohorts. Based on the strengths of the associations in Model 1 vs Model 3, we divided the LM loci into those with an effect on both lean mass and fat mass in the same direction and refer to those as "sumo wrestler" loci (FTO and MC4R). In contrast, loci with an impact specifically on LM were termed "body builder" loci (VCAN and ADAMTSL3). Using existing available genome-wide association study databases, LM increasing alleles of SNPs in sumo wrestler loci were associated with an adverse metabolic profile, whereas LM increasing alleles of SNPs in "body builder" loci were associated with metabolic protection. Conclusions In conclusion, we identified one novel LM locus (TNRC6B). Our results suggest that a genetically determined increase in lean mass might exert either harmful or protective effects on metabolic traits, depending on its relation to fat mass.
Characterization of Male-Produced Aggregation Pheromone of the Bean Flower Thrips Megalurothrips sjostedti (Thysanoptera: Thripidae)
Niassy, Saliou ; Tamiru, Amanuel ; Hamilton, James G.C. ; Kirk, William D.J. ; Mumm, R. ; Sims, Cassie ; Kogel, W.J. de; Ekesi, Sunday ; Maniania, N.K. ; Bandi, Krishnakumari ; Mitchell, Fraser ; Subramanian, Sevgan - \ 2019
Journal of Chemical Ecology 45 (2019). - ISSN 0098-0331 - p. 348 - 355.
Aggregation of the bean flower thrips, Megalurothrips sjostedti (Trybom) (Thysanoptera: Thripidae), has been observed on cowpea, Vigna unguiculata (L.) Walp. To understand the mechanism underpinning this behavior, we studied
the responses of M. sjostedti to headspace volatiles from conspecifics in a four-arm olfactometer. Both male and female M. sjostedti were attracted to male, but not to female odor. Gas chromatography/mass spectrometry (GC/
MS) analyses revealed the presence of two distinct compounds in male M. sjostedti headspace, namely (R)-lavandulyl 3-methylbutanoate (major compound) and (R)-lavandulol (minor compound); by contrast, both compounds were only present in trace amounts in female headspace collections. A behavioral assay using synthetic compounds showed that male M. sjostedti was attracted to both (R)-lavandulyl 3-methylbutanoate and (R)-lavandulol, while females responded only to (R)-lavandulyl 3-methylbutanoate. This is the first report of a male-produced aggregation pheromone in the genus Megalurothrips. The bean flower thrips is the primary pest of cowpea, which is widely grown in sub-Saharan Africa. The attraction of male and female M. sjostedti to these compounds offers an opportunity to develop ecologically sustainable management methods for M. sjostedti in Africa.
Diacylglycerol acyltransferase 1 contributes to freezing tolerance
Arisz, Steven A. ; Heo, Jae-Yun ; Koevoets, Iko Tamar ; Zhao, Tao ; Egmond, Pieter van; Meyer, Jessica ; Zeng, Weiqing ; Niu, Xiaomu ; Wang, Baosheng ; Mitchell-Olds, Thomas ; Schranz, M.E. ; Testerink, Christa - \ 2018
Plant Physiology 177 (2018)4. - ISSN 0032-0889 - p. 1410 - 1424.
Freezing limits plant growth and crop productivity, and plant species in temperate zones have the capacity to develop freezing tolerance through complex modulation of gene expression affecting various aspects of metabolism and physiology. While many components of freezing tolerance have been identified in model species under controlled laboratory conditions, little is known about the mechanisms that impart freezing tolerance in natural populations of wild species. Here, we performed a quantitative trait locus (QTL) study of acclimated freezing tolerance in seedlings of Boechera stricta, a highly adapted relative of Arabidopsis thaliana native to the Rocky Mountains. A single QTL was identified that contained the gene encoding ACYL-COA:DIACYLGLYCEROL ACYLTRANSFERASE 1 (BstDGAT1), whose expression is highly cold responsive. The primary metabolic enzyme DGAT1 catalyzes the final step in assembly of triacylglycerol (TAG) by acyl transfer from acyl-CoA to diacylglycerol. Freezing tolerant plants showed higher DGAT1 expression during cold acclimation than more sensitive plants and this resulted in increased accumulation of TAG in response to subsequent freezing. Levels of oligogalactolipids which are produced by SFR2 (SENSITIVE TO FREEZING 2), an indispensable element of freezing tolerance in Arabidopsis, were also higher in freezing tolerant plants. Furthermore, overexpression of AtDGAT1 led to increased freezing tolerance. We propose that DGAT1 confers freezing tolerance in plants by supporting SFR2-mediated remodeling of chloroplast membranes.
Understanding meta-population trends of the Australian fur seal, with insights for adaptive monitoring
McIntosh, Rebecca R. ; Kirkman, Steve P. ; Thalmann, Sam ; Sutherland, Duncan R. ; Mitchell, Anthony ; Arnould, John P.Y. ; Salton, Marcus ; Slip, David J. ; Dann, Peter ; Kirkwood, Roger - \ 2018
PLoS ONE 13 (2018)9. - ISSN 1932-6203
Effective ecosystem-based management requires estimates of abundance and population trends of species of interest. Trend analyses are often limited due to sparse or short-term abundance estimates for populations that can be logistically difficult to monitor over time. Therefore it is critical to assess regularly the quality of the metrics in long-term monitoring programs. For a monitoring program to provide meaningful data and remain relevant, it needs to incorporate technological improvements and the changing requirements of stakeholders, while maintaining the integrity of the data. In this paper we critically examine the monitoring program for the Australian fur seal (AFS) Arctocephalus pusillus doriferus as an example of an ad-hoc monitoring program that was co-ordinated across multiple stakeholders as a range-wide census of live pups in the Austral summers of 2002, 2007 and 2013. This 5-yearly census, combined with historic counts at individual sites, successfully tracked increasing population trends as signs of population recovery up to 2007. The 2013 census identified the first reduction in AFS pup numbers (14,248 live pups, -4.2% change per annum since 2007), however we have limited information to understand this change. We analyse the trends at breeding colonies and perform a power analysis to critically examine the reliability of those trends. We then assess the gaps in the monitoring program and discuss how we may transition this surveillance style program to an adaptive monitoring program than can evolve over time and achieve its goals. The census results are used for ecosystem-based modelling for fisheries management and emergency response planning. The ultimate goal for this program is to obtain the data we need with minimal cost, effort and impact on the fur seals. In conclusion we identify the importance of power analyses for interpreting trends, the value of regularly assessing long-term monitoring programs and proper design so that adaptive monitoring principles can be applied.
The functional change and deletion of FLC homologs contribute to the evolution of rapid flowering in Boechera stricta
Lee, Cheng-Ruei ; Hsieh, Jo-Wei ; Schranz, M.E. ; Mitchell-Olds, Thomas - \ 2018
Frontiers in Plant Science 9 (2018). - ISSN 1664-462X
Differences in the timing of vegetative-to-reproductive phase transition have evolved independently and repeatedly in different plant species. Due to their specific biological functions and positions in pathways, some genes are important targets of repeated evolution – independent mutations on these genes caused the evolution of similar phenotypes in distantly related organisms. While many studies have investigated these genes, it remains unclear how gene duplications influence repeated phenotypic evolution. Here we characterized the genetic architecture underlying a novel rapid-flowering phenotype in Boechera stricta and investigated the candidate genes BsFLC1 and BsFLC2. The expression patterns of BsFLC1 suggested its function in flowering time suppression, and the deletion of BsFLC1 is associated with rapid flowering and loss of vernalization requirement. In contrast, BsFLC2 did not appear to be associated with flowering and had accumulated multiple amino acid substitutions in the relatively short evolutionary timeframe after gene duplication. These non-synonymous substitutions greatly changed the physicochemical properties of the original amino acids, concentrated non-randomly near a protein-interacting domain, and had greater substitution rate than synonymous changes. Here we suggested that, after recent gene duplication of the FLC gene, the evolution of rapid phenology was made possible by the change of BsFLC2 expression pattern or protein sequences and the deletion of BsFLC1.
Crop pests and predators exhibit inconsistent responses to surrounding landscape composition
Karp, Daniel S. ; Chaplin-Kramer, Rebecca ; Meehan, Timothy D. ; Martin, Emily A. ; Declerck, Fabrice ; Grab, Heather ; Gratton, Claudio ; Hunt, Lauren ; Larsen, Ashley E. ; Martínez-Salinas, Alejandra ; O’Rourke, Megan E. ; Rusch, Adrien ; Poveda, Katja ; Jonsson, Mattias ; Rosenheim, Jay A. ; Schellhorn, Nancy A. ; Tscharntke, Teja ; Wratten, Stephen D. ; Zhang, Wei ; Iverson, Aaron L. ; Adler, Lynn S. ; Albrecht, Matthias ; Alignier, Audrey ; Angelella, Gina M. ; Zubair Anjum, Muhammad ; Avelino, Jacques ; Batáry, Péter ; Baveco, Johannes M. ; Bianchi, Felix J.J.A. ; Birkhofer, Klaus ; Bohnenblust, Eric W. ; Bommarco, Riccardo ; Brewer, Michael J. ; Caballero-López, Berta ; Carrière, Yves ; Carvalheiro, Luísa G. ; Cayuela, Luis ; Centrella, Mary ; Ćetković, Aleksandar ; Henri, Dominic Charles ; Chabert, Ariane ; Costamagna, Alejandro C. ; La Mora, Aldo De; Kraker, Joop De; Desneux, Nicolas ; Diehl, Eva ; Diekötter, Tim ; Dormann, Carsten F. ; Eckberg, James O. ; Entling, Martin H. ; Fiedler, Daniela ; Franck, Pierre ; Veen, F.J.F. van; Frank, Thomas ; Gagic, Vesna ; Garratt, Michael P.D. ; Getachew, Awraris ; Gonthier, David J. ; Goodell, Peter B. ; Graziosi, Ignazio ; Groves, Russell L. ; Gurr, Geoff M. ; Hajian-Forooshani, Zachary ; Heimpel, George E. ; Herrmann, John D. ; Huseth, Anders S. ; Inclán, Diego J. ; Ingrao, Adam J. ; Iv, Phirun ; Jacot, Katja ; Johnson, Gregg A. ; Jones, Laura ; Kaiser, Marina ; Kaser, Joe M. ; Keasar, Tamar ; Kim, Tania N. ; Kishinevsky, Miriam ; Landis, Douglas A. ; Lavandero, Blas ; Lavigne, Claire ; Ralec, Anne Le; Lemessa, Debissa ; Letourneau, Deborah K. ; Liere, Heidi ; Lu, Yanhui ; Lubin, Yael ; Luttermoser, Tim ; Maas, Bea ; Mace, Kevi ; Madeira, Filipe ; Mader, Viktoria ; Cortesero, Anne Marie ; Marini, Lorenzo ; Martinez, Eliana ; Martinson, Holly M. ; Menozzi, Philippe ; Mitchell, Matthew G.E. ; Miyashita, Tadashi ; Molina, Gonzalo A.R. ; Molina-Montenegro, Marco A. ; O’Neal, Matthew E. ; Opatovsky, Itai ; Ortiz-Martinez, Sebaastian ; Nash, Michael ; Östman, Örjan ; Ouin, Annie ; Pak, Damie ; Paredes, Daniel ; Parsa, Soroush ; Parry, Hazel ; Perez-Alvarez, Ricardo ; Perović, David J. ; Peterson, Julie A. ; Petit, Sandrine ; Philpott, Stacy M. ; Plantegenest, Manuel ; Plećaš, Milan ; Pluess, Therese ; Pons, Xavier ; Potts, Simon G. ; Pywell, Richard F. ; Ragsdale, David W. ; Rand, Tatyana A. ; Raymond, Lucie ; Ricci, Benoît ; Sargent, Chris ; Sarthou, Jean-Pierre ; Saulais, Julia ; Schäckermann, Jessica ; Schmidt, Nick P. ; Schneider, Gudrun ; Schüepp, Christof ; Sivakoff, Frances S. ; Smith, Henrik G. ; Stack Whitney, Kaitlin ; Stutz, Sonja ; Szendrei, Zsofia ; Takada, Mayura B. ; Taki, Hisatomo ; Tamburini, Giovanni ; Thomson, Linda J. ; Tricault, Yann ; Tsafack, Noelline ; Tschumi, Matthias ; Valantin-Morison, Muriel ; Trinh, Mai Van; Werf, Wopke Van Der; Vierling, Kerri T. ; Werling, Ben P. ; Wickens, Jennifer B. ; Wickens, Victoria J. ; Woodcock, Ben A. ; Wyckhuys, Kris ; Xiao, Haijun ; Yasuda, Mika ; Yoshioka, Akira - \ 2018
Proceedings of the National Academy of Sciences of the United States of America 115 (2018)33. - ISSN 0027-8424 - p. E7863 - E7870.
The idea that noncrop habitat enhances pest control and represents a win–win opportunity to conserve biodiversity and bolster yields has emerged as an agroecological paradigm. However, while noncrop habitat in landscapes surrounding farms sometimes benefits pest predators, natural enemy responses remain heterogeneous across studies and effects on pests are inconclusive. The observed heterogeneity in species responses to noncrop habitat may be biological in origin or could result from variation in how habitat and biocontrol are measured. Here, we use a pest-control database encompassing 132 studies and 6,759 sites worldwide to model natural enemy and pest abundances, predation rates, and crop damage as a function of landscape composition. Our results showed that although landscape composition explained significant variation within studies, pest and enemy abundances, predation rates, crop damage, and yields each exhibited different responses across studies, sometimes increasing and sometimes decreasing in landscapes with more noncrop habitat but overall showing no consistent trend. Thus, models that used landscape-composition variables to predict pest-control dynamics demonstrated little potential to explain variation across studies, though prediction did improve when comparing studies with similar crop and landscape features. Overall, our work shows that surrounding noncrop habitat does not consistently improve pest management, meaning habitat conservation may bolster production in some systems and depress yields in others. Future efforts to develop tools that inform farmers when habitat conservation truly represents a win–win would benefit from increased understanding of how landscape effects are modulated by local farm management and the biology of pests and their enemies.
Soil protists: A fertile frontier in soil biology research
Geisen, Stefan ; Mitchell, Edward A.D. ; Adl, Sina ; Bonkowski, Michael ; Dunthorn, Micah ; Ekelund, Flemming ; Fernández, Leonardo D. ; Jousset, Alexandre ; Krashevska, Valentyna ; Singer, David ; Spiegel, Frederick W. ; Walochnik, Julia ; Lara, Enrique - \ 2018
FEMS Microbiology Reviews 42 (2018)3. - ISSN 0168-6445 - p. 293 - 323.
Biogeography - Functional diversity - Plant performance - Soil food web - Soil microbiome - Taxonomic diversity
Protists include all eukaryotes except plants, fungi and animals. They are an essential, yet often forgotten, component of the soil microbiome. Method developments have now furthered our understanding of the real taxonomic and functional diversity of soil protists. They occupy key roles in microbial foodwebs as consumers of bacteria, fungi and other small eukaryotes. As parasites of plants, animals and even of larger protists, they regulate populations and shape communities. Pathogenic forms play a major role in public health issues as human parasites, or act as agricultural pests. Predatory soil protists release nutrients enhancing plant growth. Soil protists are of key importance for our understanding of eukaryotic evolution and microbial biogeography. Soil protists are also useful in applied research as bioindicators of soil quality, as models in ecotoxicology and as potential biofertilizers and biocontrol agents. In this review, we provide an overview of the enormous morphological, taxonomical and functional diversity of soil protists, and discuss current challenges and opportunities in soil protistology. Research in soil biology would clearly benefit from incorporating more protistology alongside the study of bacteria, fungi and animals.
Responses of competitive understorey species to spatial environmental gradients inaccurately explain temporal changes
Lombaerde, Emiel De; Verheyen, Kris ; Perring, Michael P. ; Bernhardt-Römermann, Markus ; Calster, Hans Van; Brunet, Jörg ; Chudomelová, Markéta ; Decocq, Guillaume ; Diekmann, Martin ; Durak, Tomasz ; Hédl, Radim ; Heinken, Thilo ; Hommel, Patrick ; Jaroszewicz, Bogdan ; Kopecký, Martin ; Lenoir, Jonathan ; Macek, Martin ; Máliš, František ; Mitchell, Fraser J.G. ; Naaf, Tobias ; Newman, Miles ; Petřík, Petr ; Reczyńska, Kamila ; Schmidt, Wolfgang ; Świerkosz, Krzysztof ; Vild, Ondřej ; Wulf, Monika ; Baeten, Lander - \ 2018
Basic and Applied Ecology 30 (2018). - ISSN 1439-1791 - p. 52 - 64.
Canopy - Chronosequence - Cover abundance - forestREplot - Global change - Herb layer - Nitrogen deposition - Spatiotemporal resurvey data - Temperate forest - Tree regeneration
Understorey plant communities play a key role in the functioning of forest ecosystems. Under favourable environmental conditions, competitive understorey species may develop high abundances and influence important ecosystem processes such as tree regeneration. Thus, understanding and predicting the response of competitive understorey species as a function of changing environmental conditions is important for forest managers. In the absence of sufficient temporal data to quantify actual vegetation changes, space-for-time (SFT) substitution is often used, i.e. studies that use environmental gradients across space to infer vegetation responses to environmental change over time. Here we assess the validity of such SFT approaches and analysed 36 resurvey studies from ancient forests with low levels of recent disturbances across temperate Europe to assess how six competitive understorey plant species respond to gradients of overstorey cover, soil conditions, atmospheric N deposition and climatic conditions over space and time. The combination of historical and contemporary surveys allows (i) to test if observed contemporary patterns across space are consistent at the time of the historical survey, and, crucially, (ii) to assess whether changes in abundance over time given recorded environmental change match expectations from patterns recorded along environmental gradients in space. We found consistent spatial relationships at the two periods: local variation in soil variables and overstorey cover were the best predictors of individual species’ cover while interregional variation in coarse-scale variables, i.e. N deposition and climate, was less important. However, we found that our SFT approach could not accurately explain the large variation in abundance changes over time. We thus recommend to be cautious when using SFT substitution to infer species responses to temporal changes.
Effect of model root exudate on denitrifier community dynamics and activity at different water-filled pore space levels in a fertilised soil
Langarica-Fuentes, Adrian ; Manrubia, Marta ; Giles, Madeline E. ; Mitchell, Susan ; Daniell, Tim J. - \ 2018
Soil Biology and Biochemistry 120 (2018). - ISSN 0038-0717 - p. 70 - 79.
Denitrification - Microbial community dynamics - nirK - nirS - Nitrous oxide emissions - nosZ - Root exudate addition
Although a “rhizosphere effect” on denitrification rates has been established, a clear understanding of the effects of exudate addition on denitrifier community dynamics remains elusive. A microcosm experiment was designed to explore the interaction between exudate addition and soil moisture on community dynamics and denitrification rates. Artificial root exudate at 5 different carbon concentrations was added daily to soil microcosms at contrasting target WFPS (50, 70 and 90%). After a 7-day period, total denitrification and N2O emission rates were measured and community dynamics assessed using molecular methods. The response of denitrifier genes to exudate addition was different, with nirS and nosZ-I showing a stronger effect than nirK and nosZ-II. Distinct community structures were observed for nirS and nosZ-I at 90% target WFPS when compared to 50% and 70%. NirS denitrifier population size showed a ca. 5-Fold increase in gene copy number at 90% WFPS when exudate was added at the highest C input. Significant total denitrification and N2O emission rates were observed only at 90% WFPS, which increased with C input. Our study improves the understanding of the complex interaction between microbial communities, the abiotic environment and process rates which can inform management practices aimed at increasing complete denitrification and controlling greenhouse gas production from agriculture.
Global environmental change effects on plant community composition trajectories depend upon management legacies
Perring, Michael P. ; Bernhardt-Römermann, Markus ; Baeten, Lander ; Midolo, Gabriele ; Blondeel, Haben ; Depauw, Leen ; Landuyt, Dries ; Maes, Sybryn L. ; Lombaerde, Emiel De; Carón, Maria Mercedes ; Vellend, Mark ; Brunet, Jörg ; Chudomelová, Markéta ; Decocq, Guillaume ; Diekmann, Martin ; Dirnböck, Thomas ; Dörfler, Inken ; Durak, Tomasz ; Frenne, Pieter De; Gilliam, Frank S. ; Hédl, Radim ; Heinken, Thilo ; Hommel, Patrick ; Jaroszewicz, Bogdan ; Kirby, Keith J. ; Kopecký, Martin ; Lenoir, Jonathan ; Li, Daijiang ; Máliš, František ; Mitchell, Fraser J.G. ; Naaf, Tobias ; Newman, Miles ; Petřík, Petr ; Reczyńska, Kamila ; Schmidt, Wolfgang ; Standovár, Tibor ; Świerkosz, Krzysztof ; Calster, Hans Van; Vild, Ondřej ; Wagner, Eva Rosa ; Wulf, Monika ; Verheyen, Kris - \ 2018
Global Change Biology 24 (2018)4. - ISSN 1354-1013 - p. 1722 - 1740.
Biodiversity change - Climate change - Disturbance regime - ForestREplot - Herbaceous layer - Management intensity - Nitrogen deposition - Plant functional traits - Time lag - Vegetation resurvey
The contemporary state of functional traits and species richness in plant communities depends on legacy effects of past disturbances. Whether temporal responses of community properties to current environmental changes are altered by such legacies is, however, unknown. We expect global environmental changes to interact with land-use legacies given different community trajectories initiated by prior management, and subsequent responses to altered resources and conditions. We tested this expectation for species richness and functional traits using 1814 survey-resurvey plot pairs of understorey communities from 40 European temperate forest datasets, syntheses of management transitions since the year 1800, and a trait database. We also examined how plant community indicators of resources and conditions changed in response to management legacies and environmental change. Community trajectories were clearly influenced by interactions between management legacies from over 200 years ago and environmental change. Importantly, higher rates of nitrogen deposition led to increased species richness and plant height in forests managed less intensively in 1800 (i.e., high forests), and to decreases in forests with a more intensive historical management in 1800 (i.e., coppiced forests). There was evidence that these declines in community variables in formerly coppiced forests were ameliorated by increased rates of temperature change between surveys. Responses were generally apparent regardless of sites' contemporary management classifications, although sometimes the management transition itself, rather than historic or contemporary management types, better explained understorey responses. Main effects of environmental change were rare, although higher rates of precipitation change increased plant height, accompanied by increases in fertility indicator values. Analysis of indicator values suggested the importance of directly characterising resources and conditions to better understand legacy and environmental change effects. Accounting for legacies of past disturbance can reconcile contradictory literature results and appears crucial to anticipating future responses to global environmental change.
Seagrass ecosystem trajectory depends on the relative timescales of resistance, recovery and disturbance
O'Brien, Katherine R. ; Waycott, Michelle ; Maxwell, Paul ; Kendrick, Gary A. ; Udy, James W. ; Ferguson, Angus J.P. ; Kilminster, Kieryn ; Scanes, Peter ; McKenzie, Len J. ; McMahon, Kathryn ; Adams, Matthew P. ; Samper-Villarreal, Jimena ; Collier, Catherine ; Lyons, Mitchell ; Mumby, Peter J. ; Radke, Lynda ; Christianen, Marjolijn J.A. ; Dennison, William C. - \ 2018
Marine Pollution Bulletin 134 (2018). - ISSN 0025-326X - p. 166 - 176.
Colonizing - Opportunistic - Persistent - Recovery - Resilience - Resistance - Seagrass - Trajectory
Seagrass ecosystems are inherently dynamic, responding to environmental change across a range of scales. Habitat requirements of seagrass are well defined, but less is known about their ability to resist disturbance. Specific means of recovery after loss are particularly difficult to quantify. Here we assess the resistance and recovery capacity of 12 seagrass genera. We document four classic trajectories of degradation and recovery for seagrass ecosystems, illustrated with examples from around the world. Recovery can be rapid once conditions improve, but seagrass absence at landscape scales may persist for many decades, perpetuated by feedbacks and/or lack of seed or plant propagules to initiate recovery. It can be difficult to distinguish between slow recovery, recalcitrant degradation, and the need for a window of opportunity to trigger recovery. We propose a framework synthesizing how the spatial and temporal scales of both disturbance and seagrass response affect ecosystem trajectory and hence resilience.
Erratum: Large meta-analysis of genome-wide association studies identifies five loci for lean body mass
Zillikens, M.C. ; Demissie, Serkalem ; Hsu, Yi Hsiang ; Yerges-Armstrong, Laura M. ; Chou, Wen Chi ; Stolk, Lisette ; Livshits, Gregory ; Broer, Linda ; Johnson, Toby ; Koller, Daniel L. ; Kutalik, Zoltán ; Luan, J. ; Malkin, Ida ; Ried, Janina S. ; Smith, Albert V. ; Thorleifsson, Gudmar ; Vandenput, Liesbeth ; Hua Zhao, Jing ; Zhang, Weihua ; Aghdassi, Ali ; Åkesson, Kristina ; Amin, Najaf ; Baier, Leslie J. ; Barroso, Inês ; Bennett, David A. ; Bertram, Lars ; Biffar, Rainer ; Bochud, Murielle ; Boehnke, Michael ; Borecki, Ingrid B. ; Buchman, Aron S. ; Byberg, Liisa ; Campbell, Harry ; Campos Obanda, Natalia ; Cauley, Jane A. ; Cawthon, Peggy M. ; Cederberg, Henna ; Chen, Zhao ; Cho, Nam H. ; Jin Choi, Hyung ; Claussnitzer, Melina ; Collins, Francis ; Cummings, Steven R. ; Jager, Philip L. De; Demuth, Ilja ; Dhonukshe-Rutten, Rosalie A.M. ; Diatchenko, Luda ; Eiriksdottir, Gudny ; Enneman, Anke W. ; Erdos, Mike ; Eriksson, Johan G. ; Eriksson, Joel ; Estrada, Karol ; Evans, Daniel S. ; Feitosa, Mary F. ; Fu, Mao ; Garcia, Melissa ; Gieger, Christian ; Girke, Thomas ; Glazer, Nicole L. ; Grallert, Harald ; Grewal, Jagvir ; Han, Bok Ghee ; Hanson, Robert L. ; Hayward, Caroline ; Hofman, Albert ; Hoffman, Eric P. ; Homuth, Georg ; Hsueh, Wen Chi ; Hubal, Monica J. ; Hubbard, Alan ; Huffman, Kim M. ; Husted, Lise B. ; Illig, Thomas ; Ingelsson, Erik ; Ittermann, Till ; Jansson, John Olov ; Jordan, Joanne M. ; Jula, Antti ; Karlsson, Magnus ; Khaw, Kay Tee ; Kilpeläinen, Tuomas O. ; Klopp, Norman ; Kloth, Jacqueline S.L. ; Koistinen, Heikki A. ; Kraus, William E. ; Kritchevsky, Stephen ; Kuulasmaa, Teemu ; Kuusisto, Johanna ; Laakso, Markku ; Lahti, Jari ; Lang, Thomas ; Langdahl, Bente L. ; Launer, Lenore J. ; Lee, Jong Young ; Lerch, Markus M. ; Lewis, Joshua R. ; Lind, Lars ; Lindgren, Cecilia ; Liu, Yongmei ; Liu, Tian ; Liu, Youfang ; Ljunggren, Östen ; Lorentzon, Mattias ; Luben, Robert N. ; Maixner, William ; McGuigan, Fiona E. ; Medina-Gomez, Carolina ; Meitinger, Thomas ; Melhus, Håkan ; Mellström, Dan ; Melov, Simon ; Michaëlsson, Karl ; Mitchell, Braxton D. ; Morris, Andrew P. ; Mosekilde, Leif ; Newman, Anne ; Nielson, Carrie M. ; O'Connell, Jeffrey R. ; Oostra, Ben A. ; Orwoll, Eric S. ; Palotie, Aarno ; Parker, Stephen C.J. ; Peacock, Munro ; Perola, Markus ; Peters, Annette ; Polasek, Ozren ; Prince, Richard L. ; Räikkönen, Katri ; Ralston, Stuart H. ; Ripatti, Samuli ; Robbins, John A. ; Rotter, Jerome I. ; Rudan, Igor ; Salomaa, Veikko ; Satterfield, Suzanne ; Schadt, Eric E. ; Schipf, Sabine ; Scott, Laura ; Sehmi, Joban ; Shen, Jian ; Soo Shin, Chan ; Sigurdsson, Gunnar ; Smith, Shad ; Soranzo, Nicole ; Stančáková, Alena ; Steinhagen-Thiessen, Elisabeth ; Streeten, Elizabeth A. ; Styrkarsdottir, Unnur ; Swart, Karin M.A. ; Tan, Sian Tsung ; Tarnopolsky, Mark A. ; Thompson, Patricia ; Thomson, Cynthia A. ; Thorsteinsdottir, Unnur ; Tikkanen, Emmi ; Tranah, Gregory J. ; Tuomilehto, Jaakko ; Schoor, Natasja M. van; Verma, Arjun ; Vollenweider, Peter ; Völzke, Henry ; Wactawski-Wende, Jean ; Walker, Mark ; Weedon, Michael N. ; Welch, Ryan ; Wichmann, H.E. ; Widen, Elisabeth ; Williams, Frances M.K. ; Wilson, James F. ; Wright, Nicole C. ; Xie, Weijia ; Yu, Lei ; Zhou, Yanhua ; Chambers, John C. ; Döring, Angela ; Duijn, Cornelia M. van; Econs, Michael J. ; Gudnason, Vilmundur ; Kooner, Jaspal S. ; Psaty, Bruce M. ; Spector, Timothy D. ; Stefansson, Kari ; Rivadeneira, Fernando ; Uitterlinden, André G. ; Wareham, Nicholas J. ; Ossowski, Vicky ; Waterworth, Dawn ; Loos, Ruth J.F. ; Karasik, David ; Harris, Tamara B. ; Ohlsson, Claes ; Kiel, Douglas P. - \ 2017
Nature Communications 8 (2017)1. - ISSN 2041-1723 - 1 p.
A correction to this article has been published and is linked from the HTML version of this article.
Large-scale GWAS identifies multiple loci for hand grip strength providing biological insights into muscular fitness
Willems, Sara M. ; Wright, D.J. ; Day, Felix R. ; Trajanoska, Katerina ; Joshi, P.K. ; Morris, John A. ; Matteini, Amy M. ; Garton, Fleur C. ; Grarup, Niels ; Oskolkov, Nikolay ; Thalamuthu, Anbupalam ; Mangino, Massimo ; Liu, Jun ; Demirkan, Ayse ; Lek, Monkol ; Xu, Liwen ; Wang, Guan ; Oldmeadow, Christopher ; Gaulton, Kyle J. ; Lotta, Luca A. ; Miyamoto-Mikami, Eri ; Rivas, Manuel A. ; White, Tom ; Loh, Po Ru ; Aadahl, Mette ; Amin, Najaf ; Attia, John R. ; Austin, Krista ; Benyamin, Beben ; Brage, Søren ; Cheng, Yu Ching ; Ciȩszczyk, Paweł ; Derave, Wim ; Eriksson, Karl Fredrik ; Eynon, Nir ; Linneberg, Allan ; Lucia, Alejandro ; Massidda, Myosotis ; Mitchell, Braxton D. ; Miyachi, Motohiko ; Murakami, Haruka ; Padmanabhan, Sandosh ; Pandey, Ashutosh ; Papadimitriou, Ioannis ; Rajpal, Deepak K. ; Sale, Craig ; Schnurr, Theresia M. ; Sessa, Francesco ; Shrine, Nick ; Groot, Lisette C.P.G.M. De - \ 2017
Nature Communications 8 (2017). - ISSN 2041-1723
Hand grip strength is a widely used proxy of muscular fitness, a marker of frailty, and predictor of a range of morbidities and all-cause mortality. To investigate the genetic determinants of variation in grip strength, we perform a large-scale genetic discovery analysis in a combined sample of 195,180 individuals and identify 16 loci associated with grip strength (P<5 × 10-8) in combined analyses. A number of these loci contain genes implicated in structure and function of skeletal muscle fibres (ACTG1), neuronal maintenance and signal transduction (PEX14, TGFA, SYT1), or monogenic syndromes with involvement of psychomotor impairment (PEX14, LRPPRC and KANSL1). Mendelian randomization analyses are consistent with a causal effect of higher genetically predicted grip strength on lower fracture risk. In conclusion, our findings provide new biological insight into the mechanistic underpinnings of grip strength and the causal role of muscular strength in age-related morbidities and mortality.
Large meta-analysis of genome-wide association studies identifies five loci for lean body mass
Zillikens, M.C. ; Demissie, Serkalem ; Hsu, Yi Hsiang ; Yerges-Armstrong, Laura M. ; Chou, Wen Chi ; Stolk, Lisette ; Livshits, Gregory ; Broer, Linda ; Johnson, Toby ; Koller, Daniel L. ; Kutalik, Zoltán ; Luan, J.A. ; Malkin, Ida ; Ried, Janina S. ; Smith, Albert V. ; Thorleifsson, Gudmar ; Vandenput, Liesbeth ; Hua Zhao, Jing ; Zhang, Weihua ; Aghdassi, Ali ; Åkesson, Kristina ; Amin, Najaf ; Baier, Leslie J. ; Barroso, Inês ; Bennett, David A. ; Bertram, Lars ; Biffar, Rainer ; Bochud, Murielle ; Boehnke, Michael ; Borecki, Ingrid B. ; Buchman, Aron S. ; Byberg, Liisa ; Campbell, Harry ; Campos Obanda, Natalia ; Cauley, Jane A. ; Cawthon, Peggy M. ; Cederberg, Henna ; Chen, Zhao ; Cho, Nam H. ; Jin Choi, Hyung ; Claussnitzer, Melina ; Collins, Francis ; Cummings, Steven R. ; Jager, Philip L. De; Demuth, Ilja ; Dhonukshe-Rutten, Rosalie A.M. ; DIatchenko, Luda ; Eiriksdottir, Gudny ; Enneman, Anke W. ; Erdos, Mike ; Eriksson, Johan G. ; Eriksson, Joel ; Estrada, Karol ; Evans, Daniel S. ; Feitosa, Mary F. ; Fu, Mao ; Garcia, Melissa ; Gieger, Christian ; Girke, Thomas ; Glazer, Nicole L. ; Grallert, Harald ; Grewal, Jagvir ; Han, Bok Ghee ; Hanson, Robert L. ; Hayward, Caroline ; Hofman, Albert ; Hoffman, Eric P. ; Homuth, Georg ; Hsueh, Wen Chi ; Hubal, Monica J. ; Hubbard, Alan ; Huffman, Kim M. ; Husted, Lise B. ; Illig, Thomas ; Ingelsson, Erik ; Ittermann, Till ; Jansson, John Olov ; Jordan, Joanne M. ; Jula, Antti ; Karlsson, Magnus ; Khaw, Kay Tee ; Kilpelaïnen, Tuomas O. ; Klopp, Norman ; Kloth, Jacqueline S.L. ; Koistinen, Heikki A. ; Kraus, William E. ; Kritchevsky, Stephen ; Kuulasmaa, Teemu ; Kuusisto, Johanna ; Laakso, Markku ; Lahti, Jari ; Lang, Thomas ; Langdahl, Bente L. ; Launer, Lenore J. ; Lee, Jong Young ; Lerch, Markus M. ; Lewis, Joshua R. ; Lind, Lars ; Lindgren, Cecilia M. ; Liu, Yongmei ; Liu, Tian ; Liu, Youfang ; Ljunggren, Östen ; Lorentzon, Mattias ; Luben, Robert N. ; Maixner, William ; McGuigan, Fiona E. ; Medina-Gomez, Carolina ; Meitinger, Thomas ; Melhus, Håkan ; Mellström, Dan ; Melov, Simon ; Michaëlsson, Karl ; Mitchell, Braxton D. ; Morris, Andrew P. ; Mosekilde, Leif ; Newman, Anne ; Nielson, Carrie M. ; O'Connell, Jeffrey R. ; Oostra, Ben A. ; Orwoll, Eric S. ; Palotie, Aarno ; Parker, Stephan ; Peacock, Munro ; Perola, Markus ; Peters, Annette ; Polasek, Ozren ; Prince, Richard L. ; Raïkkönen, Katri ; Ralston, Stuart H. ; Ripatti, Samuli ; Robbins, John A. ; Rotter, Jerome I. ; Rudan, Igor ; Salomaa, Veikko ; Satterfield, Suzanne ; Schadt, Eric E. ; Schipf, Sabine ; Scott, Laura ; Sehmi, Joban ; Shen, Jian ; Soo Shin, Chan ; Sigurdsson, Gunnar ; Smith, Shad ; Soranzo, Nicole ; Stančáková, Alena ; Steinhagen-Thiessen, Elisabeth ; Streeten, Elizabeth A. ; Styrkarsdottir, Unnur ; Swart, Karin M.A. ; Tan, Sian Tsung ; Tarnopolsky, Mark A. ; Thompson, Patricia ; Thomson, Cynthia A. ; Thorsteinsdottir, Unnur ; Tikkanen, Emmi ; Tranah, Gregory J. ; Tuomilehto, Jaakko ; Schoor, Natasja M. van; Verma, Arjun ; Vollenweider, Peter ; Völzke, Henry ; Wactawski-Wende, Jean ; Walker, Mark ; Weedon, Michael N. ; Welch, Ryan ; Wichman, H.E. ; Widen, Elisabeth ; Williams, Frances M.K. ; Wilson, James F. ; Wright, Nicole C. ; Xie, Weijia ; Yu, Lei ; Zhou, Yanhua ; Chambers, John C. ; Döring, Angela ; Duijn, Cornelia M. Van; Econs, Michael J. ; Gudnason, Vilmundur ; Kooner, Jaspal S. ; Psaty, Bruce M. ; Spector, Timothy D. ; Stefansson, Kari ; Rivadeneira, Fernando ; Uitterlinden, André G. ; Wareham, Nicholas J. ; Ossowski, Vicky ; Waterworth, Dawn M. ; Loos, Ruth J.F. ; Karasik, David ; Harris, Tamara B. ; Ohlsson, Claes ; Kiel, Douglas P. - \ 2017
Nature Communications 8 (2017)1. - ISSN 2041-1723
Lean body mass, consisting mostly of skeletal muscle, is important for healthy aging. We performed a genome-wide association study for whole body (20 cohorts of European ancestry with n = 38,292) and appendicular (arms and legs) lean body mass (n = 28,330) measured using dual energy X-ray absorptiometry or bioelectrical impedance analysis, adjusted for sex, age, height, and fat mass. Twenty-one single-nucleotide polymorphisms were significantly associated with lean body mass either genome wide (p < 5 × 10-8) or suggestively genome wide (p < 2.3 × 10-6). Replication in 63,475 (47,227 of European ancestry) individuals from 33 cohorts for whole body lean body mass and in 45,090 (42,360 of European ancestry) subjects from 25 cohorts for appendicular lean body mass was successful for five single-nucleotide polymorphisms in/near HSD17B11, VCAN, ADAMTSL3, IRS1, and FTO for total lean body mass and for three single-nucleotide polymorphisms in/near VCAN, ADAMTSL3, and IRS1 for appendicular lean body mass. Our findings provide new insight into the genetics of lean body mass.
Low-Frequency Synonymous Coding Variation in CYP2R1 Has Large Effects on Vitamin D Levels and Risk of Multiple Sclerosis
Manousaki, Despoina ; Dudding, Tom ; Haworth, Simon ; Hsu, Yi Hsiang ; Liu, Ching Ti ; Medina-Gómez, Carolina ; Voortman, Trudy ; Velde, Nathalie Van Der; Melhus, Håkan ; Vandenput, Liesbeth ; Noordam, Raymond ; Forgetta, Vincenzo ; Greenwood, Celia M.T. ; Biggs, Mary L. ; Psaty, Bruce M. ; Rotter, Jerome I. ; Zemel, Babette S. ; Mitchell, Jonathan A. ; Taylor, Bruce ; Lorentzon, Mattias ; Karlsson, Magnus ; Jaddoe, Vincent W.V. ; Tiemeier, Henning ; Campos-Obando, Natalia ; Franco, Oscar H. ; Utterlinden, Andre G. ; Broer, Linda ; Schoor, Natasja M. van; Ham, Annelies C. ; Ikram, Arfan M.A. ; Karasik, David ; Mutsert, Renée De; Rosendaal, Frits R. ; Heijer, Martin den; Wang, Thomas J. ; Lind, Lars ; Orwoll, Eric S. ; Mook-Kanamori, Dennis O. ; Michaëlsson, Karl ; Kestenbaum, Bryan ; Ohlsson, Claes ; Mellström, Dan ; Groot, Lisette C.P.G.M. de; Grant, Struan F.A. ; Kiel, Douglas P. ; Zillikens, M.C. ; Rivadeneira, Fernando ; Sawcer, Stephen ; Timpson, Nicholas J. ; Richards, J.B. - \ 2017
American Journal of Human Genetics 101 (2017)2. - ISSN 0002-9297 - p. 227 - 238.
GWAS - Low-frequency genetic variants - Multiple sclerosis - Vitamin D
Vitamin D insufficiency is common, correctable, and influenced by genetic factors, and it has been associated with risk of several diseases. We sought to identify low-frequency genetic variants that strongly increase the risk of vitamin D insufficiency and tested their effect on risk of multiple sclerosis, a disease influenced by low vitamin D concentrations. We used whole-genome sequencing data from 2,619 individuals through the UK10K program and deep-imputation data from 39,655 individuals genotyped genome-wide. Meta-analysis of the summary statistics from 19 cohorts identified in CYP2R1 the low-frequency (minor allele frequency = 2.5%) synonymous coding variant g.14900931G>A (p.Asp120Asp) (rs117913124[A]), which conferred a large effect on 25-hydroxyvitamin D (25OHD) levels (-0.43 SD of standardized natural log-transformed 25OHD per A allele; p value = 1.5 × 10-88). The effect on 25OHD was four times larger and independent of the effect of a previously described common variant near CYP2R1. By analyzing 8,711 individuals, we showed that heterozygote carriers of this low-frequency variant have an increased risk of vitamin D insufficiency (odds ratio [OR] = 2.2, 95% confidence interval [CI] = 1.78-2.78, p = 1.26 × 10-12). Individuals carrying one copy of this variant also had increased odds of multiple sclerosis (OR = 1.4, 95% CI = 1.19-1.64, p = 2.63 × 10-5) in a sample of 5,927 case and 5,599 control subjects. In conclusion, we describe a low-frequency CYP2R1 coding variant that exerts the largest effect upon 25OHD levels identified to date in the general European population and implicates vitamin D in the etiology of multiple sclerosis.
AntiSMASH 4.0 - improvements in chemistry prediction and gene cluster boundary identification
Blin, Kai ; Wolf, Thomas ; Chevrette, Marc G. ; Lu, Xiaowen ; Schwalen, Christopher J. ; Kautsar, Satria A. ; Suarez Duran, Hernando G. ; Los Santos, Emmanuel L.C. De; Kim, Hyun Uk ; Nave, Mariana ; Dickschat, Jeroen S. ; Mitchell, Douglas A. ; Shelest, Ekaterina ; Breitling, Rainer ; Takano, Eriko ; Lee, Sang Yup ; Weber, Tilmann ; Medema, Marnix H. - \ 2017
Nucleic acids research 45 (2017)W1. - ISSN 0305-1048 - p. W36 - W41.
Many antibiotics, chemotherapeutics, crop protection agents and food preservatives originate from molecules produced by bacteria, fungi or plants. In recent years, genome mining methodologies have been widely adopted to identify and characterize the biosynthetic gene clusters encoding the production of such compounds. Since 2011, the â € antibiotics and secondary metabolite analysis shell - antiSMASH' has assisted researchers in efficiently performing this, both as a web server and a standalone tool. Here, we present the thoroughly updated antiSMASH version 4, which adds several novel features, including prediction of gene cluster boundaries using the ClusterFinder method or the newly integrated CASSIS algorithm, improved substrate specificity prediction for non-ribosomal peptide synthetase adenylation domains based on the new SANDPUMA algorithm, improved predictions for terpene and ribosomally synthesized and post-translationally modified peptides cluster products, reporting of sequence similarity to proteins encoded in experimentally characterized gene clusters on a per-protein basis and a domain-level alignment tool for comparative analysis of trans-AT polyketide synthase assembly line architectures. Additionally, several usability features have been updated and improved. Together, these improvements make antiSMASH up-to-date with the latest developments in natural product research and will further facilitate computational genome mining for the discovery of novel bioactive molecules.
Stadium Coltan : artisanal mining, reforms and social change in eastern Democratic Republic of Congo
Wakenge, Claude Iguma - \ 2017
Wageningen University. Promotor(en): D.J.M. Hilhorst, co-promotor(en): K. Vlassenroot; J.G.R. Cuvelier. - Wageningen : Wageningen University - ISBN 9789463434560 - 210
mining - conflict - economic sociology - cooperatives - reconstruction - poverty - rural sociology - workers - feedstocks - minerals - congo democratic republic - central africa - mijnbouw - conflict - economische sociologie - coöperaties - reconstructie - armoede - rurale sociologie - werkers - industriële grondstoffen - mineralen - democratische republiek kongo - centraal-afrika
In the Democratic Republic of Congo (DRC), the mining sector has the potential to play a pivotal role in post-conflict reconstruction (World Bank, 2008), and artisanal mining sustains the livelihoods of millions people in the country (PACT, 2010). However, in the last 15 years, minerals from this artisanal mining have been ill-reputed. Eastern DRC has often been characterised by chronic instability and violent conflicts (Autesserre, 2010; Stearns, 2011) because it is widely believed that minerals in this region have attracted the greed of national and foreign armed groups, who benefit from the mining business.
Although this ‘greed hypothesis’ has been criticised for its inconsistent performance in explaining resource-related conflicts (Le Billon, 2010; Ross, 2006), various national and international reform initiatives have gained momentum (Verbruggen et al., 2011). These initiatives aim to make the Congolese artisanal mining sector more transparent and to prevent ‘conflict minerals’ from entering the international market. In 2014, 13 reform initiatives—10 focusing on 3T (tantalum, tin and tungsten) and three on gold—were operational in eastern DRC (Cuvelier et al. 2014: 5). The implicit assumptions are that mining reforms will fully ‘clean’ artisanal mining of violence and corruption and that this will contribute to sustaining people’s livelihoods (Garrett and Mitchell, 2009: 12).
This study investigated initiatives intended to ‘formalise’ artisanal mining in DRC—in other words, they aimed to bring mining under state control. The study especially focuses on the effects of one among these initiatives—the ITRI Tin Supply Chain Initiative (iTSCi)—on two groups of actors: miners (creuseurs) and middlemen (négociants). This thesis thus presents a fine-grained case study of the iTSCi. Designed by the International Tin Research Institute in 2009, iTSCi provides a means of determining the origin of 3T and documenting the trading chain for these minerals by ‘tagging and bagging’ the loads of 3T near miners’ shafts (at postes d’achat/selling points or buying stations), at counting offices (comptoirs) and in mineral depots, before the minerals are exported through the international market.
This is a qualitative study undertaken at three coltan mining sites of northern Katanga: Kahendwa, Kisengo and Mai-Baridi. Coltan has been extracted at these sites since 2007. From March 2013 to September 2014, data were collected using participant observation of people’s practices (extraction/sale of coltan and various types of interactions between trading houses, cooperatives, mineworkers (creuseurs) and middlemen (négociants), as well as detailed in-depth interviews with creuseurs, négociants and their households. Data were also collected from the staff of mining cooperatives, trading houses, state authorities and civil servants—predominantly of the Service d’Assistance et d’Encadrement du Small-Scale Mining (SAESSCAM) and the Division des Mines. The last group of informants were a group of clandestine coltan négociants (known as hiboux—literally, ‘owls’), who were followed in the study.
The purpose of this research is to study the micro-dynamics of changes after the reforms following the implementation of iTSCi. The study thus provides insights into how iTSCi is concretely implemented and how it has altered the organisation of mining and the trade of coltan. The study also aims to examine how this organisation affected creuseurs and négociants. The main research question of this study is as follows:
How have initiatives to reform artisanal mining (iTSCi in particular) affected institutional change, how does this relate to changes in patterns of coltan production and trade, how were creuseurs and négociants affected by these changes, and how did these groups respond in the coltan mining areas of Kahendwa, Kisengo and Mai Baridi (northern Katanga) from 2009 to 2014?
Analytically, the study adopted three main theoretical perspectives. First, an actor-oriented approach was taken, building on the premise that individual actors have the agency, knowledge and experience to reflect upon their situation and to respond to changes in their surrounding context (Giddens, 1984). Although the examined mining reforms consist predominantly of ‘ready-made’ techniques such as iTSCi’s ‘tagging and bagging’, analysing reforms with an actor orientation helps to highlight people’s reactions and responses. This includes how reform policies are applied in institutions (e.g. mining cooperatives), how they interact, how they are assigned meaning and how they are negotiated by social actors (Christoplos and Hilhorst, 2009).
Second, the study builds on the sociology of economic life, which holds that economic action is a form of social action that is socially ‘embedded’, meaning that it is linked with or dependent on actions and institutions (such as social networks) that are noneconomic in content, goals and processes (Granovetter, 2005). This perspective facilitates the analysis of the livelihoods of négociants, including mechanisms of smuggling minerals into and beyond the mining areas where iTSCi is in force.
Third, this thesis introduced the original concept of ‘enclaves of regulations’. These enclaves refer to the mining areas where iTSCi or other reforms are in force. This thesis has shown that, although these ‘enclaves’ appear to be ‘closed’ and insulated from the environment in terms of the locally applied rules for the mining and trading of minerals (e.g. ‘tagging and bagging’), in reality, such closure is not complete. This thesis has demonstrated that it would therefore be more appropriate to consider these ‘enclaves’ as semi-autonomous fields with porous boundaries.
Apart from the introduction and the concluding chapters, this thesis is composed of five chapters. Chapter 2 explores the evolution of the mineral sector in the Katanga province. It analyses the history of mining, the initiation of artisanal mining and how the ongoing reforms have been informed by this history. In this chapter, it is shown that there is a long history of the organisation of mining in the Katangese province. The reforms therefore did not enter into a stage of anarchy, or an institutional void, but they added a layer to already existing forms of organisation.
Chapter 3 focuses on mining cooperatives as newly introduced institutions aimed at governing the artisanal mining sites. Through a single case study, the chapter analyses how these cooperatives —especially the Coopérative des Artisanaux Miniers du Congo, CDMC—were introduced into the mining areas and how they interacted and blended with pre-existing miners’ organisations. This chapter demonstrates that cooperatives have been an emergent—rather than durable—solution in terms of representing the interests of artisanal miners.
In Chapter 4, I provide a different perspective on ‘conflict minerals’. I thus introduce the notion of ‘reform conflicts’ to emphasise that, although ongoing reforms aim to sever the supposed linkages between the artisanal mining business and violent conflicts, these reforms have become a driving force behind the emergence of new conflicts over property rights and access to minerals.
Chapter 5 is about livelihoods. It analyses how the reforms have influenced the livelihoods and socioeconomic position of négociants. This chapter also explores what kind of opportunities the reforms have offered to this group of mineral brokers often considered powerful in the mineral supply chain and explains what kind of constraints the négociants have confronted and why they have opted to diversify their livelihood portfolios. The chapter has shown that the reforms have affected this group of mineral brokers in different ways. Some négociants were well off, whereas others have been excluded from the mineral commodity chain. These findings contradict the widespread opinion that négociants are always abusive brokers in the mineral production and commodity chain.
Chapter 6 analyses the responses of creuseurs and négociants to iTSCi. Although the mining sites where iTSCi is in force appear to be ‘enclaves of regulations’, I explore the strategies of creuseurs and négociants to bypass iTSCi and the reforms, especially around the coltan trade. This chapter demonstrates that coltan smuggling is a deeply rooted practice. Despite the reforms, smuggling continues in different forms.
All of the elements highlighted above suggest that mining reforms have undergone a major shift, from addressing the initial problems associated with ‘conflict minerals’ to creating or reinforcing various types of problems, such as the influence of ‘big men’ in the mining business, coltan smuggling and the emergence of new conflicts over accessing minerals. This means that reform initiatives such as iTSCi should be based on knowledge about the actual situation. Thus, understanding and addressing these new types of problems calls for a comprehensive approach at both local and broader levels.
Current remote sensing approaches to monitoring forest degradation in support of countries measurement, reporting and verification (MRV) systems for REDD+
Mitchell, Anthea L. ; Rosenqvist, Ake ; Mora, Brice - \ 2017
Carbon Balance and Management 12 (2017)1. - ISSN 1750-0680
Above-ground biomass - Carbon emissions - Degradation - Disturbance - Forests - Measurement reporting and verification - Monitoring - REDD+ - Time-series
Forest degradation is a global phenomenon and while being an important indicator and precursor to further forest loss, carbon emissions due to degradation should also be accounted for in national reporting within the frame of UN REDD+. At regional to country scales, methods have been progressively developed to detect and map forest degradation, with these based on multi-resolution optical, synthetic aperture radar (SAR) and/or LiDAR data. However, there is no one single method that can be applied to monitor forest degradation, largely due to the specific nature of the degradation type or process and the timeframe over which it is observed. The review assesses two main approaches to monitoring forest degradation: first, where detection is indicated by a change in canopy cover or proxies, and second, the quantification of loss (or gain) in above ground biomass (AGB). The discussion only considers degradation that has a visible impact on the forest canopy and is thus detectable by remote sensing. The first approach encompasses methods that characterise the type of degradation and track disturbance, detect gaps in, and fragmentation of, the forest canopy, and proxies that provide evidence of forestry activity. Progress in these topics has seen the extension of methods to higher resolution (both spatial and temporal) data to better capture the disturbance signal, distinguish degraded and intact forest, and monitor regrowth. Improvements in the reliability of mapping methods are anticipated by SAR-optical data fusion and use of very high resolution data. The second approach exploits EO sensors with known sensitivity to forest structure and biomass and discusses monitoring efforts using repeat LiDAR and SAR data. There has been progress in the capacity to discriminate forest age and growth stage using data fusion methods and LiDAR height metrics. Interferometric SAR and LiDAR have found new application in linking forest structure change to degradation in tropical forests. Estimates of AGB change have been demonstrated at national level using SAR and LiDAR-assisted approaches. Future improvements are anticipated with the availability of next generation LiDAR sensors. Improved access to relevant satellite data and best available methods are key to operational forest degradation monitoring. Countries will need to prioritise their monitoring efforts depending on the significance of the degradation, balanced against available resources. A better understanding of the drivers and impacts of degradation will help guide monitoring and restoration efforts. Ultimately we want to restore ecosystem service and function in degraded forests before the change is irreversible.
Soil protistology rebooted: 30 fundamental questions to start with
Geisen, Stefan ; Mitchell, Edward A.D. ; Wilkinson, David M. ; Adl, Sina ; Bonkowski, Michael ; Brown, Matthew W. ; Fiore-Donno, Anna Maria ; Heger, Thierry J. ; Jassey, Vincent E.J. ; Krashevska, Valentyna ; Lahr, Daniel J.G. ; Marcisz, Katarzyna ; Mulot, Matthieu ; Payne, Richard ; Singer, David ; Anderson, O.R. ; Charman, Dan J. ; Ekelund, Flemming ; Griffiths, Bryan S. ; Rønn, Regin ; Smirnov, Alexey ; Bass, David ; Belbahri, Lassaâd ; Berney, Cédric ; Blandenier, Quentin ; Chatzinotas, Antonis ; Clarholm, Marianne ; Dunthorn, Micah ; Feest, Alan ; Fernández, Leonardo D. ; Foissner, Wilhelm ; Fournier, Bertrand ; Gentekaki, Eleni ; Hájek, Michal ; Helder, Hans ; Jousset, Alexandre ; Koller, Robert ; Kumar, Santosh ; Terza, Antonietta La; Lamentowicz, Mariusz ; Mazei, Yuri ; Santos, Susana S. ; Seppey, Christophe V.W. ; Spiegel, Frederick W. ; Walochnik, Julia ; Winding, Anne ; Lara, Enrique - \ 2017
Soil Biology and Biochemistry 111 (2017). - ISSN 0038-0717 - p. 94 - 103.
Protists are the most diverse eukaryotes. These microbes are keystone organisms of soil ecosystems and
regulate essential processes of soil fertility such as nutrient cycling and plant growth. Despite this,
protists have received little scientific attention, especially compared to bacteria, fungi and nematodes in
soil studies. Recent methodological advances, particularly in molecular biology techniques, have made
the study of soil protists more accessible, and have created a resurgence of interest in soil protistology.
This ongoing revolution now enables comprehensive investigations of the structure and functioning of
soil protist communities, paving the way to a new era in soil biology. Instead of providing an exhaustive
review, we provide a synthesis of research gaps that should be prioritized in future studies of soil
protistology to guide this rapidly developing research area. Based on a synthesis of expert opinion we
propose 30 key questions covering a broad range of topics including evolution, phylogenetics, functional
ecology, macroecology, paleoecology, and methodologies. These questions highlight a diversity of topics
that will establish soil protistology as a hub discipline connecting different fundamental and applied
fields such as ecology, biogeography, evolution, plant-microbe interactions, agronomy, and conservation
biology. We are convinced that soil protistology has the potential to be one of the most exciting frontiers
The genome of Chenopodium quinoa
Jarvis, D.E. ; Shwen Ho, Yung ; Lightfoot, Damien J. ; Schmöckel, Sandra M. ; Li, Bo ; Borm, T.J.A. ; Ohyanagi, Hajime ; Mineta, Katsuhiko ; Mitchell, Craig T. ; Saber, Noha ; Kharbatia, Najeh M. ; Rupper, Ryan R. ; Sharp, Aaron R. ; Dally, Nadine ; Boughton, Berin A. ; Woo, Yong H. ; Gao, Ge ; Schijlen, E.G.W.M. ; Guo, Xiujie ; Momin, Afaque A. ; Negräo, Sónia ; Al-Babili, Salim ; Gehring, Christoph ; Roessner, Ute ; Jung, Christian ; Murphy, Kevin ; Arold, Stefan T. ; Gojobori, Takashi ; Linden, C.G. van der; Loo, E.N. van; Jellen, Eric N. ; Maughan, Peter J. ; Tester, Mark - \ 2017
Nature 542 (2017)7641. - ISSN 0028-0836 - p. 307 - 312.
Chenopodium quinoa (quinoa) is a highly nutritious grain identified as an important crop to improve world food security. Unfortunately, few resources are available to facilitate its genetic improvement. Here we report the assembly of a high-quality, chromosome-scale reference genome sequence for quinoa, which was produced using single-molecule real-time sequencing in combination with optical, chromosome-contact and genetic maps. We also report the sequencing of two diploids from the ancestral gene pools of quinoa, which enables the identification of sub-genomes in quinoa, and reduced-coverage genome sequences for 22 other samples of the allotetraploid goosefoot complex. The genome sequence facilitated the identification of the transcription factor likely to control the production of anti-nutritional triterpenoid saponins found in quinoa seeds, including a mutation that appears to cause alternative splicing and a premature stop codon in sweet quinoa strains. These genomic resources are an important first step towards the genetic improvement of quinoa.
Nutrition for the ageing brain: Towards evidence for an optimal diet
Vauzour, David ; Camprubi-Robles, Maria ; Miquel-Kergoat, Sophie ; Andres-Lacueva, Cristina ; Bánáti, Diána ; Barberger-Gateau, Pascale ; Bowman, Gene L. ; Caberlotto, Laura ; Clarke, Robert ; Hogervorst, Eef ; Kiliaan, Amanda J. ; Lucca, Ugo ; Manach, Claudine ; Minihane, Anne-Marie ; Mitchell, Ellen Siobhan ; Perneczky, Robert ; Perry, Hugh ; Roussel, Anne-Marie ; Schuermans, Jeroen ; Sijben, John ; Spencer, Jeremy P.E. ; Thuret, Sandrine ; De Rest, Ondine Van; Vandewoude, Maurits ; Wesnes, Keith ; Williams, Robert J. ; Williams, Robin S.B. ; Ramirez, Maria - \ 2017
Ageing Research Reviews 35 (2017). - ISSN 1568-1637 - p. 222 - 240.
As people age they become increasingly susceptible to chronic and extremely debilitating brain diseases. The precise cause of the neuronal degeneration underlying these disorders, and indeed normal brain ageing remains however elusive. Considering the limits of existing preventive methods, there is a desire to develop effective and safe strategies. Growing preclinical and clinical research in healthy individuals or at the early stage of cognitive decline has demonstrated the beneficial impact of nutrition on cognitive functions. The present review is the most recent in a series produced by the Nutrition and Mental Performance Task Force under the auspice of the International Life Sciences Institute Europe (ILSI Europe). The latest scientific advances specific to how dietary nutrients and non-nutrient may affect cognitive ageing are presented. Furthermore, several key points related to mechanisms contributing to brain ageing, pathological conditions affecting brain function, and brain biomarkers are also discussed. Overall, findings are inconsistent and fragmented and more research is warranted to determine the underlying mechanisms and to establish dose-response relationships for optimal brain maintenance in different population subgroups. Such approaches are likely to provide the necessary evidence to develop research portfolios that will inform about new dietary recommendations on how to prevent cognitive decline.
Genome-wide analysis identifies 12 loci influencing human reproductive behavior
Barban, Nicola ; Jansen, Rick ; Vlaming, Ronald de; Vaez, Ahmad ; Mandemakers, Jornt J. ; Tropf, Felix C. ; Shen, Xia ; Wilson, James F. ; Chasman, Daniel I. ; Nolte, Ilja M. ; Tragante, Vinicius ; Laan, Sander W. van der; Perry, John R.B. ; Kong, Augustine ; Ahluwalia, Tarunveer S. ; Albrecht, Eva ; Yerges-Armstrong, Laura ; Atzmon, Gil ; Auro, Kirsi ; Ayers, Kristin ; Bakshi, Andrew ; Ben-Avraham, Danny ; Berger, Klaus ; Bergman, Aviv ; Bertram, Lars ; Bielak, Lawrence F. ; Bjornsdottir, Gyda ; Bonder, Marc Jan ; Broer, Linda ; Bui, Minh ; Barbieri, Caterina ; Cavadino, Alana ; Chavarro, Jorge E. ; Turman, Constance ; Concas, Maria Pina ; Cordell, Heather J. ; Davies, Gail ; Eibich, Peter ; Eriksson, Nicholas ; Esko, Tõnu ; Eriksson, Joel ; Falahi, Fahimeh ; Felix, Janine F. ; Fontana, Mark Alan ; Franke, Lude ; Gandin, Ilaria ; Gaskins, Audrey J. ; Gieger, Christian ; Gunderson, Erica P. ; Guo, Xiuqing ; Hayward, Caroline ; He, Chunyan ; Hofer, Edith ; Huang, Hongyan ; Joshi, Peter K. ; Kanoni, Stavroula ; Karlsson, Robert ; Kiechl, Stefan ; Kifley, Annette ; Kluttig, Alexander ; Kraft, Peter ; Lagou, Vasiliki ; Lecoeur, Cecile ; Lahti, Jari ; Li-Gao, Ruifang ; Lind, Penelope A. ; Liu, Tian ; Makalic, Enes ; Mamasoula, Crysovalanto ; Matteson, Lindsay ; Mbarek, Hamdi ; McArdle, Patrick F. ; McMahon, George ; Meddens, S.F.W. ; Mihailov, Evelin ; Miller, Mike ; Missmer, Stacey A. ; Monnereau, Claire ; Most, Peter J. van der; Myhre, Ronny ; Nalls, Mike A. ; Nutile, Teresa ; Kalafati, Ioanna Panagiota ; Porcu, Eleonora ; Prokopenko, Inga ; Rajan, Kumar B. ; Rich-Edwards, Janet ; Rietveld, Cornelius A. ; Robino, Antonietta ; Rose, Lynda M. ; Rueedi, Rico ; Ryan, Kathleen A. ; Saba, Yasaman ; Schmidt, Daniel ; Smith, Jennifer A. ; Stolk, Lisette ; Streeten, Elizabeth ; Tönjes, Anke ; Thorleifsson, Gudmar ; Ulivi, Sheila ; Wedenoja, Juho ; Wellmann, Juergen ; Willeit, Peter ; Yao, Jie ; Yengo, Loic ; Zhao, Jing Hua ; Zhao, Wei ; Zhernakova, Daria V. ; Amin, Najaf ; Andrews, Howard ; Balkau, Beverley ; Barzilai, Nir ; Bergmann, Sven ; Biino, Ginevra ; Bisgaard, Hans ; Bønnelykke, Klaus ; Boomsma, Dorret I. ; Buring, Julie E. ; Campbell, Harry ; Cappellani, Stefania ; Ciullo, Marina ; Cox, Simon R. ; Cucca, Francesco ; Toniolo, Daniela ; Davey-Smith, George ; Deary, Ian J. ; Dedoussis, George ; Deloukas, Panos ; Duijn, Cornelia M. van; Geus, Eco J.C. de; Eriksson, Johan G. ; Evans, Denis A. ; Faul, Jessica D. ; Sala, Cinzia Felicita ; Froguel, Philippe ; Gasparini, Paolo ; Girotto, Giorgia ; Grabe, Hans-Jörgen ; Greiser, Karin Halina ; Groenen, Patrick J.F. ; Haan, Hugoline G. de; Haerting, Johannes ; Harris, Tamara B. ; Heath, Andrew C. ; Heikkilä, Kauko ; Hofman, Albert ; Homuth, Georg ; Holliday, Elizabeth G. ; Hopper, John ; Hyppönen, Elina ; Jacobsson, Bo ; Jaddoe, Vincent W.V. ; Johannesson, Magnus ; Jugessur, Astanand ; Kähönen, Mika ; Kajantie, Eero ; Kardia, Sharon L.R. ; Keavney, Bernard ; Kolcic, Ivana ; Koponen, Päivikki ; Kovacs, Peter ; Kronenberg, Florian ; Kutalik, Zoltan ; Bianca, Martina la; Lachance, Genevieve ; Iacono, William G. ; Lai, Sandra ; Lehtimäki, Terho ; Liewald, David C. ; Lindgren, Cecilia M. ; Liu, Yongmei ; Luben, Robert ; Lucht, Michael ; Luoto, Riitta ; Magnus, Per ; Magnusson, Patrik K.E. ; Martin, Nicholas G. ; McGue, Matt ; McQuillan, Ruth ; Medland, Sarah E. ; Meisinger, Christa ; Mellström, Dan ; Metspalu, Andres ; Traglia, Michela ; Milani, Lili ; Mitchell, Paul ; Montgomery, Grant W. ; Mook-Kanamori, Dennis ; Mutsert, Renée de; Nohr, Ellen A. ; Ohlsson, Claes ; Olsen, Jørn ; Ong, Ken K. ; Paternoster, Lavinia ; Pattie, Alison ; Penninx, Brenda W.J.H. ; Perola, Markus ; Peyser, Patricia A. ; Pirastu, Mario ; Polasek, Ozren ; Power, Chris ; Kaprio, Jaakko ; Raffel, Leslie J. ; Räikkönen, Katri ; Raitakari, Olli ; Ridker, Paul M. ; Ring, Susan M. ; Roll, Kathryn ; Rudan, Igor ; Ruggiero, Daniela ; Rujescu, Dan ; Salomaa, Veikko ; Schlessinger, David ; Schmidt, Helena ; Schmidt, Reinhold ; Schupf, Nicole ; Smit, Johannes ; Sorice, Rossella ; Spector, Tim D. ; Starr, John M. ; Stöckl, Doris ; Strauch, Konstantin ; Stumvoll, Michael ; Swertz, Morris A. ; Thorsteinsdottir, Unnur ; Thurik, A.R. ; Timpson, Nicholas J. ; Tung, Joyce Y. ; Uitterlinden, André G. ; Vaccargiu, Simona ; Viikari, Jorma ; Vitart, Veronique ; Völzke, Henry ; Vollenweider, Peter ; Vuckovic, Dragana ; Waage, Johannes ; Wagner, Gert G. ; Wang, Jie Jin ; Wareham, Nicholas J. ; Weir, David R. ; Willemsen, Gonneke ; Willeit, Johann ; Wright, Alan F. ; Zondervan, Krina T. ; Stefansson, Kari ; Krueger, Robert F. ; Lee, James J. ; Benjamin, Daniel J. ; Cesarini, David ; Koellinger, Philipp D. ; Hoed, Marcel den; Snieder, Harold ; Mills, Melinda C. - \ 2016
Nature Genetics 48 (2016)12. - ISSN 1061-4036 - p. 1462 - 1472.
The genetic architecture of human reproductive behavior—age at first birth (AFB) and number of children ever born (NEB)—has a strong relationship with fitness, human development, infertility and risk of neuropsychiatric disorders. However, very few genetic loci have been identified, and the underlying mechanisms of AFB and NEB are poorly understood. We report a large genome-wide association study of both sexes including 251,151 individuals for AFB and 343,072 individuals for NEB. We identified 12 independent loci that are significantly associated with AFB and/or NEB in a SNP-based genome-wide association study and 4 additional loci associated in a gene-based effort. These loci harbor genes that are likely to have a role, either directly or by affecting non-local gene expression, in human reproduction and infertility, thereby increasing understanding of these complex traits.
|Results of a desk study on best practices for animal transport
Mitchell, M.A. ; Spoolder, H.A.M. - \ 2016
In: Book of Abstracts of the 67th Annual Meeting of the European Association for Animal Production. - EAAP scientific committee - ISBN 9789086868308 - p. 531 - 531.
The EU has provides a harmonised legal framework for animal transport. Part of that framework is the EU adopted Regulation (EC) 1/2005. The content and impact of the Regulation has been the subject of a Scientific Opinion by EFSA in 2011 followed in 2012 by an impact report from the Commission to the European
Parliament and the Council. Three key recommendations were formulated the latter of which stated ‘As regards the gap between the requirements of the legislation and available scientific evidence the Commission sees that this is best addressed by the adoption of guides to good practice’. It is expected that the development of Guides to Good and Best Practice can improve the welfare of animals during transportation, particularly by reducing national and regional differences in interpretation of the requirements of the Regulation. The
Transport Guides project was commissioned by DG SANTE to produce Guides to Good Practice for cattle, sheep, pigs, horses and poultry in the European Union (http://www.animaltransportguides.eu). The project has been undertaken by a research consortium comprised of 16 representative organisations from 9 Member States and a stakeholder platform with 10 member organisations. The first phase of this project involved the examination of a wide range of information sources and literature to identify and evaluate available recommendations for good and best practices during all stages of transport. Good practices are those that reflect the requirements in the legislation. Best Practices are defined as providing additional guidance on how to exceed legally defined minimum welfare requirements. The first results of this project include analyses of the collected information for each of the species: each species section includes analyses of the practices identified, followed by an overview of all available practices presented in tabulated form. These findings are
the basis for the development of Guides to Good and Best Practices in the next steps of the project, and will be presented at the meeting.
Impact of the shedding level on transmission of persistent infections in Mycobacterium avium subspecies paratuberculosis (MAP)
Slater, Noa ; Mitchell, Rebecca Mans ; Whitlock, Robert H. ; Fyock, Terry ; Pradhan, Abani Kumar ; Knupfer, Elena ; Schukken, Ynte Hein ; Louzoun, Yoram - \ 2016
Veterinary Research 47 (2016)1. - ISSN 0928-4249
Super-shedders are infectious individuals that contribute a disproportionate amount of infectious pathogen load to the environment. A super-shedder host may produce up to 10 000 times more pathogens than other infectious hosts. Super-shedders have been reported for multiple human and animal diseases. If their contribution to infection dynamics was linear to the pathogen load, they would dominate infection dynamics. We here focus on quantifying the effect of super-shedders on the spread of infection in natural environments to test if such an effect actually occurs in Mycobacterium avium subspecies paratuberculosis (MAP). We study a case where the infection dynamics and the bacterial load shed by each host at every point in time are known. Using a maximum likelihood approach, we estimate the parameters of a model with multiple transmission routes, including direct contact, indirect contact and a background infection risk. We use longitudinal data from persistent infections (MAP), where infectious individuals have a wide distribution of infectious loads, ranging upward of three orders of magnitude. We show based on these parameters that the effect of super-shedders for MAP is limited and that the effect of the individual bacterial load is limited and the relationship between bacterial load and the infectiousness is highly concave. A 1000-fold increase in the bacterial contribution is equivalent to up to a 2-3 fold increase in infectiousness.
Assessing convergence processes at the intersection of the food and pharmaceutical industries in functional food innovation using different perspectives
Bornkessel, S. - \ 2016
Wageningen University. Promotor(en): Onno Omta; Stefanie Broring. - Wageningen : Wageningen University - ISBN 9789462576599 - 129
functional foods - innovations - food industry - non-food industries - pharmacology - functionele voedingsmiddelen - innovaties - voedselindustrie - non-food industrieën - farmacologie
Assessing convergence processes at the intersection of the food and pharmaceutical industries in functional food innovation using different perspectives
The worldwide growing functional food market (e.g. Menrad, 2003, Ding et al., 2015) is based on the convergence of the food and pharmaceutical sectors (Omta, 2004, Bröring, 2005), since functional foods incorporate a nutritional as well as a health benefit (Spence, 2006, Hasler, 2002). Several studies provide a comprehensive overview of convergence definitions and their different emphases (Bröring, 2005, Curran, 2010, Hacklin, 2008, Preschitschek, 2014), mainly following the common idea summarised by the Organisation for Economic Co‐operation and Development as follows: ‘the blurring of technical and regulatory boundaries between sectors of the economy’ (OECD, 1992). On the one hand, this emerging segment offers a plethora of innovation opportunities. On the other hand, companies focusing on this emerging segment have to employ knowledge and technologies outside of their traditional expertise. The importance of innovation increases, since the emergence of the functional food market implies an intensification of competitive pressure. Due to high failure rates, there is an urgent need to improve the food innovation process (Stewart-Knox and Mitchell, 2003).
The convergence process is considered to follow the consecutive steps of science, technology and market convergence, leading to a complete industry convergence in which companies or whole industry segments fuse (Curran et al., 2010, Hacklin, 2008). Linking these steps to the simplified innovation process, the comparative perspective on the innovation and convergence processes delivers a framework with which to analyse innovation processes in converging industries using different perspectives. Therefore, the present thesis aims
Ø to evaluate convergence processes using different perspectives in order to derive an assessment framework of the innovation process in converging industries.
This study deals with the functional food sector emerging between the food and pharmaceutical industries while using certain functional ingredients as units of analysis.
The present thesis comprises two parts. It first focuses on the procedural perspective of convergence processes in order to deliver a comprehensive analysis of the complete convergence process. This is then complemented in the second part by a focus on the later steps of market and industry convergence.
In the first part, this study delivers quantitative (Chapter 2 – life cycle approach) and qualitative (Chapter 3 – perspective of innovation value chain) measures for the comprehensive analysis of the complete convergence process. While the life cycle approach focuses on the development showing the movement of complete industry sectors, the innovation value chain perspective delivers insights into the underlying strategic cross-industry activities on a company level. Next to the comprehensive analysis of the convergence process, this study delivers two levels with which to analyse the later phases in converging industries: first, the analysis of cross-industry collaborations on a company level (Chapter 4), and second, the analysis of ingredient awareness on a consumer level (Chapter 5). While the analysis on a company level delivers an approach to analyse cross-industry innovation using the resource-based view, the consumer perspective sheds light upon the consumers’ perception of the products delivered in the convergence areas.
In summary, convergence implies a changing competitive environment. The evaluation of this phenomenon is therefore of high importance for researchers and practitioners alike. This thesis enhances the research field of convergence by delivering an overall assessment framework that integrates different perspectives to screen convergence processes and to analyse converging competences. The scope and the unit of analysis, along with the adaptation of theoretical concepts, extend already existing convergence assessment approaches. Besides the analysis of the early phases of convergence processes used to anticipate industrial developments (e.g. Curran et al., 2010), the elaboration of the complete convergence process delivers an approach to face the multifaceted challenges during the innovation process in converging industries. The practical implications of this study is that it provides companies in convergence areas different measures to evaluate convergence processes in order to identify relevant convergence areas. Depending on the phase of the convergence process, the appropriate method or mixture of methods can be used to substantiate strategic corporate decisions such as for instance product positioning.
CCoAOMT down-regulation activates anthocyanin biosynthesis in petunia
Shaipulah, N.F.M. ; Muhlemann, Joëlle K. ; Woodworth, Benjamin D. ; Moerkercke, Alex Van; Verdonk, J.C. ; Ramirez, A.A. ; Haring, Michel A. ; Dudareva, Natalia ; Schuurink, Robert C. - \ 2016
Plant Physiology 170 (2016)2. - ISSN 0032-0889 - p. 717 - 731.
Anthocyanins and volatile phenylpropenes (isoeugenol and eugenol) in petunia (Petunia hybrida) flowers have the precursor 4-coumaryl coenzyme A (CoA) in common. These phenolics are produced at different stages during flower development. Anthocyanins are synthesized during early stages of flower development and sequestered in vacuoles during the lifespan of the flowers. The production of isoeugenol and eugenol starts when flowers open and peaks after anthesis. To elucidate additional biochemical steps toward (iso)eugenol production, we cloned and characterized a caffeoyl-coenzyme A O-methyltransferase (PhCCoAOMT1) from the petals of the fragrant petunia ‘Mitchell’. Recombinant PhCCoAOMT1 indeed catalyzed the methylation of caffeoyl-CoA to produce feruloyl CoA. Silencing of PhCCoAOMT1 resulted in a reduction of eugenol production but not of isoeugenol. Unexpectedly, the transgenic plants had purple-colored leaves and pink flowers, despite the fact that cv Mitchell lacks the functional R2R3-MYB master regulator ANTHOCYANIN2 and has normally white flowers. Our results indicate that down-regulation of PhCCoAOMT1 activated the anthocyanin pathway through the R2R3-MYBs PURPLE HAZE (PHZ) and DEEP PURPLE, with predominantly petunidin accumulating. Feeding cv Mitchell flowers with caffeic acid induced PHZ expression, suggesting that the metabolic perturbation of the phenylpropanoid pathway underlies the activation of the anthocyanin pathway. Our results demonstrate a role for PhCCoAOMT1 in phenylpropene production and reveal a link between PhCCoAOMT1 and anthocyanin production.
Combining satellite data for better tropical forest monitoring
Reiche, Johannes ; Lucas, Richard ; Mitchell, A.L. ; Verbesselt, Jan ; Hoekman, D.H. ; Haarpaintner, Jörg ; Kellndorfer, J.M. ; Rosenqvist, Ake ; Lehmann, E.A. ; Woodcock, C.E. ; Seifert, Frank Martin ; Herold, Martin - \ 2016
Nature Climate Change 6 (2016)2. - ISSN 1758-678X - p. 120 - 122.
Implementation of policies to reduce forest loss challenges the Earth observation community to improve forest monitoring. An important avenue for progress is the use of new satellite missions and the combining of optical and synthetic aperture radar sensor data.
Minimum Information about a Biosynthetic Gene cluster
Medema, M.H. ; Kottmann, Renzo ; Yilmaz, Pelin ; Cummings, Matthew ; Biggins, J.B. ; Blin, Kai ; Bruijn, Irene De; Chooi, Yit Heng ; Claesen, Jan ; Coates, R.C. ; Cruz-Morales, Pablo ; Duddela, Srikanth ; Düsterhus, Stephanie ; Edwards, Daniel J. ; Fewer, David P. ; Garg, Neha ; Geiger, Christoph ; Gomez-Escribano, Juan Pablo ; Greule, Anja ; Hadjithomas, Michalis ; Haines, Anthony S. ; Helfrich, Eric J.N. ; Hillwig, Matthew L. ; Ishida, Keishi ; Jones, Adam C. ; Jones, Carla S. ; Jungmann, Katrin ; Kegler, Carsten ; Kim, Hyun Uk ; Kötter, Peter ; Krug, Daniel ; Masschelein, Joleen ; Melnik, Alexey V. ; Mantovani, Simone M. ; Monroe, Emily A. ; Moore, Marcus ; Moss, Nathan ; Nützmann, Hans Wilhelm ; Pan, Guohui ; Pati, Amrita ; Petras, Daniel ; Reen, F.J. ; Rosconi, Federico ; Rui, Zhe ; Tian, Zhenhua ; Tobias, Nicholas J. ; Tsunematsu, Yuta ; Wiemann, Philipp ; Wyckoff, Elizabeth ; Yan, Xiaohui ; Yim, Grace ; Yu, Fengan ; Xie, Yunchang ; Aigle, Bertrand ; Apel, Alexander K. ; Balibar, Carl J. ; Balskus, Emily P. ; Barona-Gómez, Francisco ; Bechthold, Andreas ; Bode, Helge B. ; Borriss, Rainer ; Brady, Sean F. ; Brakhage, Axel A. ; Caffrey, Patrick ; Cheng, Yi Qiang ; Clardy, Jon ; Cox, Russell J. ; Mot, René De; Donadio, Stefano ; Donia, Mohamed S. ; Donk, Wilfred A. Van Der; Dorrestein, Pieter C. ; Doyle, Sean ; Driessen, Arnold J.M. ; Ehling-Schulz, Monika ; Entian, Karl Dieter ; Fischbach, Michael A. ; Gerwick, Lena ; Gerwick, William H. ; Gross, Harald ; Gust, Bertolt ; Hertweck, Christian ; Höfte, Monica ; Jensen, Susan E. ; Ju, Jianhua ; Katz, Leonard ; Kaysser, Leonard ; Klassen, Jonathan L. ; Keller, Nancy P. ; Kormanec, Jan ; Kuipers, Oscar P. ; Kuzuyama, Tomohisa ; Kyrpides, Nikos C. ; Kwon, Hyung Jin ; Lautru, Sylvie ; Lavigne, Rob ; Lee, Chia Y. ; Linquan, Bai ; Liu, Xinyu ; Liu, Wen ; Luzhetskyy, Andriy ; Mahmud, Taifo ; Mast, Yvonne ; Méndez, Carmen ; Metsä-Ketelä, Mikko ; Micklefield, Jason ; Mitchell, Douglas A. ; Moore, Bradley S. ; Moreira, Leonilde M. ; Müller, Rolf ; Neilan, Brett A. ; Nett, Markus ; Nielsen, Jens ; O'Gara, Fergal ; Oikawa, Hideaki ; Osbourn, Anne ; Osburne, Marcia S. ; Ostash, Bohdan ; Payne, Shelley M. ; Pernodet, Jean Luc ; Petricek, Miroslav ; Piel, Jörn ; Ploux, Olivier ; Raaijmakers, Jos M. ; Salas, José A. ; Schmitt, Esther K. ; Scott, Barry ; Seipke, Ryan F. ; Shen, Ben ; Sherman, David H. ; Sivonen, Kaarina ; Smanski, Michael J. ; Sosio, Margherita ; Stegmann, Evi ; Süssmuth, Roderich D. ; Tahlan, Kapil ; Thomas, Christopher M. ; Tang, Yi ; Truman, Andrew W. ; Viaud, Muriel ; Walton, Jonathan D. ; Walsh, Christopher T. ; Weber, Tilmann ; Wezel, Gilles P. Van; Wilkinson, Barrie ; Willey, Joanne M. ; Wohlleben, Wolfgang ; Wright, Gerard D. ; Ziemert, Nadine ; Zhang, Changsheng ; Zotchev, Sergey B. ; Breitling, Rainer ; Takano, Eriko ; Glöckner, Frank Oliver - \ 2015
Nature Chemical Biology 11 (2015)9. - ISSN 1552-4450 - p. 625 - 631.
A wide variety of enzymatic pathways that produce specialized metabolites in bacteria, fungi and plants are known to be encoded in biosynthetic gene clusters. Information about these clusters, pathways and metabolites is currently dispersed throughout the literature, making it difficult to exploit. To facilitate consistent and systematic deposition and retrieval of data on biosynthetic gene clusters, we propose the Minimum Information about a Biosynthetic Gene cluster (MIBiG) data standard.
Differences in intermittent and continuous fecal shedding patterns between natural and experimental Mycobacterium avium subspecies paratuberculosis infections in cattle
Mitchell, R.M. ; Schukken, Ynte ; Koets, A.P. ; Weber, Maarten ; Bakker, D. ; Stabel, Judy ; Whitlock, R.H. ; Louzoun, Yoram - \ 2015
Veterinary Research 46 (2015). - ISSN 0928-4249 - 10 p.
The objective of this paper is to study shedding patterns of cows infected with Mycobacterium avium subsp. paratuberculosis (MAP). While multiple single farm studies of MAP dynamics were reported, there is not large scale meta-analysis of both natural and experimental infections. Large difference in shedding patterns between experimentally and naturally infected cows were observed. Experimental infections are thus probably driven by different pathological mechanisms. For further evaluations of shedding patterns only natural infections were used. Within such infections, the transition to high shedding was studied as a proxy to the development of a clinical disease. The majority of studied cows never developed high shedding levels. Those that do, typically never reduced their shedding level to low or no shedding. Cows that eventually became high shedders showed a pattern of continuous shedding. In contrast, cows with an intermittent shedding pattern had a low probability to ever become high shedders. In addition, cows that start shedding at a younger age (less than three years of age) have a lower hazard of becoming high shedders compared to cows starting to shed at an older age. These data suggest the presence of three categories of immune control. Cows that are intermittent shedders have the infection process under control (no progressive infection). Cows that start shedding persistently at a young age partially control the infection, but eventually will be high shedders (slow progressive infection), while cows that start shedding persistently at an older age cannot effectively control the infection and become high shedders rapidly.
Root exudates can control soil N dynamics
Langarica Fuentes, A. ; Mitchell, S. ; Manrubia Freixa, M. ; Daniell, T. - \ 2015
In: Proceedings of Rhizosphere 4 Conference Stretching the Interface of Life. - - p. 168 - 168.
Agriculture represents the dominant source of the potent greenhouse gas nitrous oxide (N2O). This is largely due to the conversion of added nitrogen-based fertiliser through the action of the microbial nitrogen cycle in soil. Denitrification represents the main source of nitrous oxide emission and is a carbon driven process, as it maintains respiration under low oxygen conditions with nitrogen oxides acting as alternative electron acceptors. Initial experiments using barley plants (Hordeum vulgare) indicated that different cultivars support significant variation in N2O emission from denitrification from associated soil and that these effects are connected to root exudation difference rather than direct interaction or litter effects. In this study, a controlled microcosm experiment was designed to explore the interaction between root exudation and denitrification in terms of N2O production and community dynamics. Different quantities of artificial root exudates were added daily to soil at three different water regimes. N2O emissions were measured and community dynamics were assessed using T-RFLP and real time PCR. Results suggest that N2O emissions are driven by nitrous oxide reductase activity (consumption) rather than nitrite reductase activity (production). Soil condition, through differential aerobic status and variability, also appeared to have a marked effect both on flux through denitrification and community dynamics. Further work is underway to dissect the role of exudation quality in driving the alteration in nitrogen cycle flux and the end product of denitrification.
Review of Priority Research & Development Topics: R&D related to the use of Remote Sensing in National Forest Monitoring
Mitchell, A. ; Hoekman, D.H. - \ 2014
Geneva, Switzerland : GEO-GFOI (GEO-GFOI R&D-document, version 1 GEO-GFOI R&D-document, version 1) - ISBN 9789299004753 - 163 p.
This document reviews the potential of the various remote sensing-derived forest map products that can be used in implementing and improving national forest monitoring systems8 and help meet the requirements of the IPCC Guidelines. It identifies any research and development topics that need to be addressed to ensure that these products can be widely used by forest countries around the world. The Global Forest Observations Initiative (GFOI) aims to facilitate the supply and use of earth observation information, so that all countries can better manage their forest resources. Initially GFOI aims to support countries’ national forest monitoring systems in accordance with the IPCC Guidelines such as the systems needed to implement the United National Framework Convention on Climate Change (UNFCCC) programme on REDD+ (reducing emissions from deforestation; forest degradation; conservation of forest carbon stocks; sustainable management of forests; and enhancement of forest carbon stocks). GFOI was set up by the Group on Earth Observations (GEO) and has the active support and involvement of 13 space agencies (and data providers). It has been explicitly endorsed by 90 countries plus the EU and 67 international organisations. GFOI engages and coordinates with key organisations and institutions such as the UNFCCC, FAO, World Bank and IPCC as well as developing country participants. GFOI developed from the GEO Forest Carbon Tracking project which successfully demonstrated its approach through selected national demonstrator countries and which started in 2008.GFOI has identified a list of thematic forest map product specifications (see next section) that can be derived from a combination of Earth Observation and ground measurement data, and that are needed for countries to measure and report their changes in carbon stocks in forests and the subsequent greenhouse emissions. A country may not need to use all of these products: their choice will depend on their national circumstances and the additional objectives they have. This review considers these products and for each determines what, if any, additional research and development may be needed before the products can be widely used and recommended for use in long term systematic forest monitoring. These R&D topics are then prioritised by both needs expressed by countries and by the IPCC ´s Greenhouse Gas (GHG) inventory good practice requirements of transparency, completeness, consistency, comparability and accuracy, as endorsed by the UNFCCC. The need for forest information may extend beyond NFMS, MRV, and GHGI objectives. Indeed, the nine societal benefit areas of GEO need some type of information about the forests. Information about the status of forest resources is used in forestry operations, natural resource assessment, conservation and reserve planning and illegal logging detection systems. Similar forest map products may be useful for biodiversity initiatives such as GEOBON. The GEO Initiative provides a unique opportunity for coordination of data and information between different sectors. Global Initiatives such as GEO and GEOBON should consult on cross-cutting information needs and the possibility of generating a suite of forest map products that serve different purposes across sectors. The current report is the first step in the development of a comprehensive R&D Plan. This Plan will be further developed by the GFOI Office, based on inputs from demonstrator countries, interested organisations and relevant research expertise. Priority Research Topics will be presented to donors for funding.
|Inter-organizational network analysis in synergy parks
Nuhoff-Isakhanyan, G. ; Wubben, E.F.M. ; Omta, S.W.F. - \ 2014
Organizational collaborations are important means for organizations to access new resources and enhance the sustainable performance. Recent examples of inter-organizational collaborations towards more sustainable production are synergy parks, such as eco-industrial parks and agroparks. Synergy parks are collaborations among organizations across different sectors, mainly from agriculture and industry, aiming at enhanced economic and environmental performance, sustainable agri-food and bio-energy production through exchanging waste and by-products, creating production synergies. Because synergy parks connect organizations in their non-core business activities, these organizations are not always keen in the realization of synergy parks. A synergy park consists of multiple organizations from various sectors linked through multiple ties, its coordination can be explained by means of organizational network theory (Van de Ven & Fery, 1980). Consequently, a synergy park can be seen as a network where companies are the nodes and their collaborations the ties. Companies with direct ties, can affect the behavior of one another (Rowley, 1997). Recently more and more scholars use network analysis in understanding firms, stakeholders, and their social and behavioral phenomena (Ahuja, 2000; Ahuja, et al., 2009; Corsaro, et al., 2012; Gulati, 2007; Gulati, et al., 2000). Theories that discuss organizational networks, however, pay more attention to relations at dyadic level. Network analysis use in understanding firms, stakeholders, and their social and behavioral phenomena beyond dyadic level is slowly increasing (Ackermann & Eden, 2011; Frooman, 1999; Rowley, 1997). It provides scholars new insights to develop the inter-organizational network theory, to further it from dyadic relationship and examine systems of dyadic interactions capturing the influence of multiple and interdependent relations on network development. The purpose of the study is to understand how the structure of inter-organizational networks impact the realization of synergy parks by analyzing network attributes. In this study we answer the following questions: What is the impact of the network structure attributes (size, type of relation, centrality, and density) on realization of inter-organizational collaborations, such as a synergy park? What alternative network structures are effective in different inter-organizational collaborations? We suggest the following propositions: 1) The relation between the size of the network and the potential of a synergy park realization has an inverse convex shape (n shape) 2) Companies connected with both formal and informal ties have stronger and enduring relationships than the ones connected with formal ties only. 3) Decentralized and dense network structures are more suited for the realization of a synergy park if the set of involved companies are more heterogeneous. We conducted cross-case analysis in three synergy parks through using mixed qualitative and quantitative methods. The unit of analysis is the exchange relationship among the organizations within the networks. We focus on formal, informal, and trust related relations. We identified the boundary spanners in each organization, and asked managers who are the most knowledgeable about the relation of other organizations in the parks. These persons are formally or informally responsible for managing the collaborative relationships with other organizations. The main method of data collection was semi-structured interviews. The network survey has complex design comparing to standard surveys, therefore, we decided to interview each respondent personally by using ONA online survey tools. Concerning to network ties, we gather value and binary data. Each tie among the same companies have been measured and analyzed separately, and compared with one another. The data is coded and analyzed by using UCINET network analysis software (Borgatti, et al., 2002; Hanneman & Riddle, 2005). Networks are framed and analyzed per synergy park separate, which is followed by the analysis across networks. The discussion and the conclusion will be presented in the full paper. Reference Ackermann, F., & Eden, C., 2011. Strategic Management of Stakeholders: Theory and Practice. Long Range Planning, 44(3): 179-196. Ahuja, G., 2000. Collaboration Networks, Structural Holes, and Innovation: A Longitudinal Study. Administrative Science Quarterly, 45(3): 425-455. Ahuja, G., Polidoro, F., & Mitchell, W., 2009. Structural homophily or social asymmetry? The formation of alliances by poorly embedded firms. Strategic Management Journal, 30(9): 941-958. Borgatti, S. P., Everett, M. G., & Freeman, L. C., 2002. UCINET for Windows, Version 6.59: Software for Social Network Analysis. Harvard, MA Analytic Technologies. Corsaro, D., Cantu, C., & Tunisini, A., 2012. Actors' Heterogeneity in Innovation Networks. Industrial Marketing Management, 41(5): 780-789. Frooman, J., 1999. Stakeholder influence strategies. Academy of Management Review, 24(2): 191-205. Gulati, R., 2007. Managing network resources: alliances, affiliations and other relational assets. Oxford: Oxford University Press. Gulati, R., Nohria, N., & Zaheer, A., 2000. Strategic networks. Strategic Management Journal, 21(3): 203-215. Hanneman, R. A., & Riddle, M., 2005. Introduction to Social Network Methods. Riverside CA: University of California. Rowley, T. J., 1997. Moving beyond dyadic ties: A network theory of stakeholder influences. Academy of Management Review, 22(4): 887-910. Van de Ven, A. H., & Fery, D. L., 1980. Measuring and Assessing Organizations: John Wiley & Sons, Inc.
Identification of quantitative trait loci and a candidate locus for freezing tolerance in controlled and outdoor environments in the overwintering crucifer Boechera stricta.
Heo, J. ; Feng, D. ; Niu, X. ; Mitchell-Olds, T. ; Tienderen, P.H. van; Tomes, D. ; Schranz, M.E. - \ 2014
Plant, Cell & Environment 37 (2014)11. - ISSN 0140-7791 - p. 2459 - 2469.
cold-acclimation - arabidopsis-thaliana - chlorophyll fluorescence - transcription factor - natural variation - frost tolerance - genes - temperature - wheat - expression
Development of chilling and freezing tolerance is complex and can be affected by photoperiod, temperature and photosynthetic performance; however, there has been limited research on the interaction of these three factors. We evaluated 108 recombinant inbred lines of Boechera stricta, derived from a cross between lines originating from Montana and Colorado, under controlled long day (LD), short-day (SD) and in an outdoor environment (OE). We measured maximum quantum yield of photosystem II, lethal temperature for 50% survival and electrolyte leakage of leaves. Our results revealed significant variation for chilling and freezing tolerance and photosynthetic performance in different environments. Using both single- and multi-trait analyses, three main-effect quantitative trait loci (QTL) were identified. QTL on linkage group (LG)3 were SD specific, whereas QTL on LG4 were found under both LD and SD. Under all conditions, QTL on LG7 were identified, but were particularly predictive for the outdoor experiment. The co-localization of photosynthetic performance and freezing tolerance effects supports these traits being co-regulated. Finally, the major QTL on LG7 is syntenic to the Arabidopsis C-repeat binding factor locus, known regulators of chilling and freezing responses in Arabidopsis thaliana and other species.
|Recovering? sea populations
Kirkwood, R.J. ; Kirkman, S. ; Arnould, J. ; Carlyon, K. ; Alderman, R. ; Mitchell, T. ; Sutherland, D. ; Brasseur, S.M.J.M. ; Aarts, G.M. - \ 2014
Nature and Health
Hartig, T. ; Mitchell, R. ; Vries, S. de; Frumkin, H. - \ 2014
Annual Review of Public Health 35 (2014). - ISSN 0163-7525 - p. 207 - 228.
urban green space - public open space - quality-of-life - physical-activity - mental-health - inner-city - possible mechanism - nature experience - social cohesion - air-quality
Urbanization, resource exploitation, and lifestyle changes have diminished possibilities for human contact with nature in urbanized societies. Concern about the loss has helped motivate research on the health benefits of contact with nature. Reviewing that research here, we focus on nature as represented by aspects of the physical environment relevant to planning, design, and policy measures that serve broad segments of urbanized societies.Wediscuss difficulties in defining “nature” and reasons for the current expansion of the research field, and we assess available reviews. We then consider research on pathways between nature and health involving air quality, physical activity, social cohesion, and stress reduction. Finally, we discuss methodological issues and priorities for future research. The extant research does describe an array of benefits of contact with nature, and evidence regarding some benefits is strong; however, some findings indicate caution is needed in applying beliefs about those benefits, and substantial gaps in knowledge remain.
|Global Forest Observations Initiative (GFOI) - Review of priority research & development Topics
Mitchell, A. ; Hoekman, D.H. - \ 2013
Geneva, Switserland : GEO-GFOI GEO Geneva (GEO-GFOI R&D document version 1.0 ) - 159 p.
On the origin and evolution of apomixis in Boechera
Lovell, J.T. ; Aliyu, O.M. ; Mau, M. ; Schranz, M.E. ; Koch, M. ; Kiefer, C. ; Song, B.H. ; Mitchell-Olds, T. ; Sharbel, T.F. - \ 2013
Plant Reproduction 26 (2013)4. - ISSN 2194-7953 - p. 309 - 315.
north-american boechera - genus boechera - holboellii brassicaceae - asexual reproduction - arabis-drummondii - hybridization - arabidopsis - angiosperms - expression - reappraisal
The genetic mechanisms causing seed development by gametophytic apomixis in plants are predominantly unknown. As apomixis is consistently associated with hybridity and polyploidy, these confounding factors may either (a) be the underlying mechanism for the expression of apomixis, or (b) obscure the genetic factors which cause apomixis. To distinguish between these hypotheses, we analyzed the population genetic patterns of diploid and triploid apomictic lineages and their sexual progenitors in the genus Boechera (Brassicaceae). We find that while triploid apomixis is associated with hybridization, the majority of diploid apomictic lineages are likely the product of intra-specific crosses. We then show that these diploid apomicts are more likely to sire triploid apomictic lineages than conspecific sexuals. Combined with flow cytometric seed screen phenotyping for male and female components of apomixis, our analyses demonstrate that hybridization is an indirect correlate of apomixis in Boechera.
Cytotoxicity of surface-functionalized silicon and germanium nanoparticles: the dominant role of surface charges
Bhattacharjee, S. ; Rietjens, I.M.C.M. ; Singh, M.P. ; Atkins, T.M. ; Purkait, T.K. ; Xu, Z. ; Regli, S. ; Shukaliak, A. ; Clark, R.J. ; Mitchell, B.S. ; Alink, G.M. ; Marcelis, A.T.M. ; Fink, M.J. ; Veinot, J.G.C. ; Kauzlarich, S.M. ; Zuilhof, H. - \ 2013
Nanoscale 5 (2013). - ISSN 2040-3364 - p. 4870 - 4883.
block copolymer nanoparticles - cerium oxide nanoparticles - quantum dots - in-vitro - oxidative stress - gold nanoparticles - cellular toxicity - dependent endocytosis - hemolytic-activity - epithelial-cells
Although it is frequently hypothesized that surface (like surface charge) and physical characteristics (like particle size) play important roles in cellular interactions of nanoparticles (NPs), a systematic study probing this issue is missing. Hence, a comparative cytotoxicity study, quantifying nine different cellular endpoints, was performed with a broad series of monodisperse, well characterized silicon (Si) and germanium (Ge) NPs with various surface functionalizations. Human colonic adenocarcinoma Caco-2 and rat alveolar macrophage NR8383 cells were used to clarify the toxicity of this series of NPs. The surface coatings on the NPs appeared to dominate the cytotoxicity: the cationic NPs exhibited cytotoxicity, whereas the carboxylic acid-terminated and hydrophilic PEG- or dextran-terminated NPs did not. Within the cationic Si NPs, smaller Si NPs were more toxic than bigger ones. Manganese-doped (1% Mn) Si NPs did not show any added toxicity, which favors their further development for bioimaging. Iron-doped (1% Fe) Si NPs showed some added toxicity, which may be due to the leaching of Fe3+ ions from the core. A silica coating seemed to impart toxicity, in line with the reported toxicity of silica. Intracellular mitochondria seem to be the target for the toxic NPs since a dose-, surface charge- and size-dependent imbalance of the mitochondrial membrane potential was observed. Such an imbalance led to a series of other cellular events for cationic NPs, like decreased mitochondrial membrane potential (¿¿m) and ATP production, induction of ROS generation, increased cytoplasmic Ca2+ content, production of TNF-a and enhanced caspase-3 activity. Taken together, the results explain the toxicity of Si NPs/Ge NPs largely by their surface characteristics, provide insight into the mode of action underlying the observed cytotoxicity, and give directions on synthesizing biocompatible Si and Ge NPs, as this is crucial for bioimaging and other applications in for example the field of medicine.
New tools for studying osteoarthritis genetics in zebrafish
Mitchell, R.E. ; Huitema, L.F. ; Skinner, R.E. ; Brunt, L.H. ; Severn, C. ; Schulte-Merker, S. ; Hammond, C.L. - \ 2013
Osteoarthritis and Cartilage 21 (2013)2. - ISSN 1063-4584 - p. 269 - 278.
nucleotide exchange factor - danio-rerio - osteogenesis-imperfecta - developing skeleton - signaling pathways - cell-migration - bone-formation - retinoic acid - expression - gdf5
Objective: Increasing evidence points to a strong genetic component to osteoarthritis (OA) and that certain changes that occur in osteoarthritic cartilage recapitulate the developmental process of endochondral ossification. As zebrafish are a well validated model for genetic studies and developmental biology, our objective was to establish the spatiotemporal expression pattern of a number of OA susceptibility genes in the larval zebrafish providing a platform for functional studies into the role of these genes in OA. Design: We identified the zebrafish homologues for Mcf2l, Gdf5, PthrP/Pthlh, Co19a2, and Col10a1 from the Ensembl genome browser. Labelled probes were generated for these genes and in situ hybridisations were performed on wild type zebrafish larvae. In addition, we generated transgenic reporter lines by modification of bacterial artificial chromosomes (BACs) containing full length promoters for col2a1 and col10a1. Results: For the first time, we show the spatiotemporal expression pattern of Mcf2l. Furthermore, we show that all six putative OA genes are dynamically expressed during zebrafish larval development, and that all are expressed in the developing skeletal system. Furthermore, we demonstrate that the transgenic reporters we have generated for col2a1 and col10al can be used to visualise chondrocyte hypertrophy in vivo. Conclusion: In this study we describe the expression pattern of six OA susceptibility genes in zebrafish larvae and the generation of two new transgenic lines marking chondrocytes at different stages of maturation. Moreover, the tools used demonstrate the utility of the zebrafish model for functional studies on genes identified as playing a role in OA. (C) 2012 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.
A gain-of-function polymorphism controlling complex traits and fitness in nature
Prasad, K.V.S.K. ; Song, B. ; Olson-Manning, C. ; Anderson, J.T. ; Lee, C. ; Schranz, Eric ; Windsor, A.J. ; Clauss, M.J. ; Manzaneda, A.J. ; Naqvi, I. ; Reichelt, M. ; Gershenzon, J. ; Rupasinghe, S.G. ; Schuler, M.A. ; Mitchell-Olds, T. - \ 2012
glucosinolate - herbivory - ecological genomics - Boechera stricta
Identification of the causal genes that control complex trait variation remains challenging, limiting our appreciation of the evolutionary processes that influence polymorphisms in nature. We cloned a quantitative trait locus that controls plant defensive chemistry, damage by insect herbivores, survival, and reproduction in the natural environments where this polymorphism evolved. These ecological effects are driven by duplications in the BCMA (branched-chain methionine allocation) loci controlling this variation and by two selectively favored amino acid changes in the glucosinolate-biosynthetic cytochrome P450 proteins that they encode. These changes cause a gain of novel enzyme function, modulated by allelic differences in catalytic rate and gene copy number. Ecological interactions in diverse environments likely contribute to the widespread polymorphism of this biochemical function.
In search of the perfect aphrodisiac: Parallel use of bitter tonics in West Africa and the Caribbean
Andel, T.R. van; Mitchell, S. ; Volpato, G. ; Vandebroek, I. ; Swier, J. ; Ruysschaert, S. ; Rentería Jiménez, C.A. ; Raes, N. - \ 2012
Journal of Ethnopharmacology 143 (2012)3. - ISSN 0378-8741 - p. 840 - 850.
male-rats - ethnobotany - medicine - cameroon
Ethnopharmacological relevance Enslaved Africans in the Americas had to reinvent their medicinal flora in an unknown environment by adhering to plants that came with them, learning from Amerindians and Europeans, using their Old World knowledge and trial and error to find substitutes for their homeland herbs. This process has left few written records, and little research has been done on transatlantic plant use. We used the composition of aphrodisiac mixtures across the black Atlantic to discuss the adaptation of herbal medicine by African diaspora in the New World. Since Africans are considered relatively recent migrants in America, their healing flora is often said to consist largely of pantropical and cultivated species, with few native trees. Therefore, we expected Caribbean recipes to be dominated by taxa that occur in both continents, poor in forest species and rich in weeds and domesticated exotics. Materials and methods To test this hypothesis, we compared botanical ingredients of 35 African and 117 Caribbean mixtures, using Dentrended Correspondence Analysis, Cluster Analysis, Indicator Species Analysis and Mann–Whitney U tests. Results Very few of the 324 ingredients were used on both continents. A slightly higher overlap on generic and family level showed that Africans did search for taxa that were botanically related to African ones, but largely selected new, unrelated plants with similar taste, appearance or pharmacological properties. Recipes from the forested Guianas contained more New World, wild and forest species than those from deforested Caribbean islands. We recorded few ‘transatlantic genera’ and weeds never dominated the recipes, so we rejected our hypothesis. Conclusions The popularity of bitter tonics in the Caribbean suggests an African heritage, but the inclusion of Neotropical species and vernacular names of plants and mixtures indicate Amerindian and European influence. We show that enslaved Africans have reinvented their herbal medicine wherever they were put to work, using the knowledge and flora that was available to them with great creativity and flexibility. Our analysis reveals how transplanted humans adapt their traditional medical practises in a new environment.
A Gain-of-Function Polymorphism Controlling Complex Traits and Fitness in Nature
Prasad, K.V.S.K. ; Song, B. ; Olson-Manning, C. ; Anderson, J.T. ; Lee, C. ; Schranz, M.E. ; Windsor, A.J. ; Clauss, M.J. ; Manzaneda, A.J. ; Naqvi, I. ; Reichelt, M. ; Gershenzon, J. ; Rupasinghe, S.G. ; Schuler, M.A. ; Mitchell-Olds, T. - \ 2012
Science 337 (2012)6098. - ISSN 0036-8075 - p. 1081 - 1084.
ecological genomics - boechera-stricta - arabidopsis - biosynthesis - cytochrome-p450 - cyp79f1 - cyp83b1 - plants
Identification of the causal genes that control complex trait variation remains challenging, limiting our appreciation of the evolutionary processes that influence polymorphisms in nature. We cloned a quantitative trait locus that controls plant defensive chemistry, damage by insect herbivores, survival, and reproduction in the natural environments where this polymorphism evolved. These ecological effects are driven by duplications in the BCMA (branched-chain methionine allocation) loci controlling this variation and by two selectively favored amino acid changes in the glucosinolate-biosynthetic cytochrome P450 proteins that they encode. These changes cause a gain of novel enzyme function, modulated by allelic differences in catalytic rate and gene copy number. Ecological interactions in diverse environments likely contribute to the widespread polymorphism of this biochemical function
Transforming governance and institutions for global sustainability: key insights from the Earth System Governance Project
Biermann, F. ; Abbott, K. ; Andresen, S. ; Bäckstrand, K. ; Bernstein, S. ; Betsill, M.M. ; Bulkeley, H. ; Cashore, B. ; Clapp, J. ; Folke, C. ; Gupta, A. ; Gupta, J. ; Haas, P.M. ; Jordan, A. ; Kanie, N. ; Kluvánková-Oravská, T. ; Lebel, L. ; Liverman, D. ; Meadowcroft, J. ; Mitchell, R.B. ; Newell, P. ; Oberthür, S. ; Olsson, L. ; Pattberg, P. ; Sánchez-Rodriguez, R. ; Schroeder, H. ; Underdal, A. ; Camargo Vieira, S. ; Vogel, C. ; Young, O.R. ; Brock, A. ; Zondervan, R. - \ 2012
Current Opinion in Environmental Sustainability 4 (2012)1. - ISSN 1877-3435 - p. 51 - 60.
social-ecological systems - environmental governance - climate-change - information disclosure - adaptive governance - regime complex - world - decentralization - accountability - transparency
The current institutional framework for sustainable development is by far not strong enough to bring about the swift transformative progress that is needed. This article contends that incrementalism—the main approach since the 1972 Stockholm Conference—will not suffice to bring about societal change at the level and speed needed to mitigate and adapt to earth system transformation. Instead, the article argues that transformative structural change in global governance is needed, and that the 2012 United Nations Conference on Sustainable Development in Rio de Janeiro must turn into a major stepping stone for a much stronger institutional framework for sustainable development. The article details core areas where urgent action is required. The article is based on an extensive social science assessment conducted by 32 members of the lead faculty, scientific steering committee, and other affiliates of the Earth System Governance Project. This Project is a ten-year research initiative under the auspices of the International Human Dimensions Programme on Global Environmental Change (IHDP), which is sponsored by the International Council for Science (ICSU), the International Social Science Council (ISSC), and the United Nations University (UNU)
Navigating the Anthropocene: Improving Earth System Governance
Biermann, F. ; Abbott, K. ; Andresen, S. ; Bäckstrand, K. ; Bernstein, S. ; Betsill, M.M. ; Bulkeley, H. ; Cashore, B. ; Clapp, J. ; Folke, C. ; Gupta, A. ; Gupta, J. ; Haas, P.M. ; Jordan, A. ; Kanie, N. ; Kluvánková-Oravská, T. ; Lebel, L. ; Liverman, D. ; Meadowcroft, J. ; Mitchell, R.B. ; Newell, P. ; Oberthür, S. ; Olsson, L. ; Pattberg, P. ; Sánchez-Rodriguez, R. ; Schroeder, H. ; Underdal, A. ; Camargo Vieira, S. ; Vogel, C. ; Young, O.R. ; Brock, A. ; Zondervan, R. - \ 2012
Science 335 (2012)6074. - ISSN 0036-8075 - p. 1306 - 1307.
Science assessments indicate that human activities are moving several of Earth's sub-systems outside the range of natural variability typical for the previous 500,000 years (1, 2). Human societies must now change course and steer away from critical tipping points in the Earth system that might lead to rapid and irreversible change (3). This requires fundamental reorientation and restructuring of national and international institutions toward more effective Earth system governance and planetary stewardship
Green cities and health: a question of scale?
Richardson, E.A. ; Mitchell, R. ; Hartig, T. ; Vries, S. de; Astell-Burt, T. ; Frumkin, H. - \ 2012
Journal of Epidemiology and Community Health 66 (2012). - ISSN 0143-005X - p. 160 - 165.
physical-activity - space - mortality - association - environment - urbanity - children
Background Cities are expanding and accommodating an increasing proportion of the world's population. It is important to identify features of urban form that promote the health of city dwellers. Access to green space has been associated with health benefits at both individual and neighbourhood level. We investigated whether a relationship between green space coverage and selected mortality rates exists at the city level in the USA. Methods An ecological cross-sectional study. A detailed land use data set was used to quantify green space for the largest US cities (n=49, combined population of 43 million). Linear regression models were used to examine the association between city-level ‘greenness’ and city-level standardised rates of mortality from heart disease, diabetes, lung cancer, motor vehicle fatalities and all causes, after adjustment for confounders. Results There was no association between greenness and mortality from heart disease, diabetes, lung cancer or automobile accidents. Mortality from all causes was significantly higher in greener cities. Conclusions While considerable evidence suggests that access to green space yields health benefits, we found no such evidence at the scale of the American city. In the USA, greener cities tend also to be more sprawling and have higher levels of car dependency. Any benefits that the green space might offer seem easily eclipsed by these other conditions and the lifestyles that accompany them. The result merits further investigation as it has important implications for how we increase green space access in our cities.
"En momentos difíciles nosotros somos un pueblo" Haciendo política en la mixteca de Oaxaca: un estudio sobre el ritual, la pasión y el poder
Curiel Covarrubias, L.C. - \ 2011
Wageningen University. Promotor(en): Georg Frerks, co-promotor(en): Monique Nuijten; Pieter de Vries. - [S.l.] : S.n. - ISBN 9789461731067 - 281
sociologie - politiek - organisatie - gewoonterecht - mexico - vs - migratie - sociology - politics - organization - customary law - mexico - usa - migration
In this thesis I decided to explain the re-functionalization of a socio-political organization regimen in a municipality located in the mixteca highlands of Oaxaca. I identified a series of events and conflicts that have been occurring since at least 15 years, and are related to the particular ways of organizing the social and political local life, known as customary law (Sistema de Usos y Costumbres-SUC). This local context is been affected by the migration to the Mexican-North American border, the incoming of federal and state financial resources as an outcome of the decentralization process, the legal recognition of the customary law in the Oaxacan Constitution, and the weakening of the influence and power of the PRI in the state. All together had form a temporal juncture since the middle 1990’s that has testified the fragmentation of the local political field. To explain this process and the relations between the different phenomena, fields of relations, actors and events is my general concern in this thesis.
The present work goes by explaining how the re-functionalization of the SUC occurs because the local political field fragmented since new emergent actors organized the people in groups around particular interests and political activism, pushing changes in the local ‚traditional‛ customs. But they also achieved to reinterpreted them to mobilize the affections and passions of the population. Also, the uses of certain discourses, practices of organization and ritualized spaces and events have been their means to achieve their goals. This have provoked the appearance of a hectic environment –specially in electoral periods- that expresses the transformations that this regime has been experienced in relation to the effects of more broader phenomena. My intention is to explain a process of change of this regimen of customary law in which new and different ways of doing politics can be observed, as well as the constitution of new local subjectivities. This happens also re-functionalizing pre-existing forms of social organization.
What I observed is that in the last years this organization regimen it’s been rationalized by new actors –emerging or previously excluded- who use discourses and practices coming out of this system –manipulating them and reinterpreting them- to participate in the new disputes and competitions for the local power, the municipal administration and the possession of ‚la costumbre‛ (the custom). These disputes take place in a fragmented and divided political field, appealing to the ‚pueblo‛ (the people) as a social entity unified and legitimate. These competitions occur between new actors grouped around leaders from political parties and social organizations, who had the capacity of destabilise the former status quo and subvert the control of the elite linked to the PRI.
Taking into account this temporal juncture, the effects of broader phenomena and what I observed during my fieldwork, I grouped my doubts and interests in these research aspects:
To expose the ways of doing politics within the process of re-functionalization of the SUC;
To show that politics has been done through the use (political, moral, ideological) of ‚la costumbre‛;
To expose the importance of the use of the discourse of ‚el pueblo‛ (as social entity) in the political struggles, and what it is expressing and meaning to who appeal to it;
To show how these ways of doing politics manifest the construction of subjectivities in a socio-political organization regime in a process of transformation.
What I present in this thesis is an extended case study (Mitchell, 2006 ). This is characterized by presenting fieldwork material organized in a time sequence (normally a long period of time) in which the same actor are involved in a series of situations and events in which their positions are redefine. Also is possible, through an extended case study, to illustrate how the ways of doing politics have been changed and how the actors involved have adapted the ideological dimension of the SUC in the context of competition, disputes and struggles for the local power. The choice of presenting the material in this way allows me to expose the analysis of a series of successive events in a period of 15 years.
I chose to do this through the analysis of discourses, practices and rituals spaces. I paid attention to the communal and public events such as assemblies and meetings but also I recur to many open and personalized interviews.
In the introduction of the thesis I expose the research problem and the way I constructed it. Also I draw on my theoretical approach, concepts and ideas about politics and the way I understand it for the purpose of this work. Also I explain the methodological path I constructed in order to develop my four main concerns.
In the second chapter I introduce the municipality of San Miguel Tlacotepec. I explain the history of the Customary Law system and its relation to Mexican politics (local and regional) and with the system of unique party. I include the particularities of this system in the ways of organized socially and politically the town. Also I explain the local institutions, its hierarchies and the role they play in the organization of the communitarian life in general. And the role domestic and international migration has been playing locally. The main goal of this chapter is to set the socio-historical context that prevails without to many and important changes for many years. Is in this context in which the firsts transformations were brewing.
I refer about these innovations in chapter 3. I illustrate the first important changes experienced in the field of the local politics. I explain how the fragmentation starts through the appearance of new actors that emerge from the experience of migration and return. They also participated in regional events that disrupt the regional politics, such as the developing of social organizations opponent to the PRI. In this context, the resources from the municipal decentralization program and the civil positions turned a coveted booty making the municipal elections the first big arena of confrontation and struggle between the new actors. I explain as well how the communal assemblies are consolidate as the legitimate organ of decision making and the new and different discourses start to emerge playing an important role in the disputes for the local power. As I expose this context from the middle of the 1990’s, I show how the trajectories of the actors developed and how new subjectivities appear in the process of reconfigure the local politics.
In chapter four I present an ethnography that show the importance of the antagonism among leaders y and organized groups as a central element to constitute the political field. I expose the kind of practices and discourses that participate –through the new leaders, activists, audience in the assemblies and confronted groups- in the dispute for ‚la costumbre‛ and how the idea of ‚el pueblo‛ was constituted -among the people who participate- and was used as a referent in the political conflict and also as a reaction to the fragmentation of the life in common. These changes also show the linkage –promote by the decentralization process- between the municipality and extra-communitarian institutions. This linkage is been reinforce through the influence the different actors have in those institutions and in the official decisions they take affecting the local dynamics of the municipality.
In chapter five the ethnography refers to the municipal election of 2007. I show the whole process of organization from the pre-electoral environment to the final resolution of the post-electoral conflict. This example is been used to demonstrate how the dispute, confrontation, personal interests and passions influenced the participation of the audience to that event. Is possible as well to observe how appealing to the customary law worked to promote personal interests, channelled the antagonism for this not to turn violence, and constitute an ideological resource that could keep the ‚pueblo‛ united in spite of division.
In chapter six I expose what apparently is a tense relation between the parish and the municipal authority. This relation occurs between the representatives of these local institutions and expresses, beyond the domestic affair, the kind of new relationship they have since the weakening of the local elite closed to the PRI and the rise of new actors who criticized the civil-religious relation. Through the ethnography of a disagreement about the use of the local chapel, my main interest is to show how the field of relationships and confrontations between these two institutions is an arena in which the representatives dispute the use of the discourse of ‚la costumbre‛ and its possession in order to win moral authority and prestige. This occurs through the strategic and instrumental use of certain rituals (from its organization to its accomplishment) and symbols, expressing the renew ways of doing politics in the changing context of the customary law system.
Chapter seven contains my final conclusions based on my findings, presented throughout these pages, and their relations to the ideas and notions that guided my reflections. This work deals with the new ways of doing politics in the light of a particular socio-political system of organization and the changes that migration, municipal decentralization, the legal recognition of the SUC and the reconfiguration of the regional political scenario brought to SMT’s politics. I show this process interpreting the re-functionalization of this system and its rationalization made by the actors who participate in the different spaces of the fragmented local political field. The observance of this process and the outcomes allow me to place this work in two different debates but related to each other: the effects of the transnational organizations en the origin communities and the possibility of the emerging of a democracy of ‚el pueblo‛ facing the ravages of a democratic unease that affects the Mexican politics in general.
To draw on the first of these debates, I argue how the transnational politics has been subordinate to the local and regional politics. In this case these two reinforce –through the leaders relations and influence- the links between the municipality and the extra-local institutions without promoting a transnational governance. The leaders arrived from the experience of transnational and domestic migration invested their experiences to reinforce their presence and influence in the local and regional political fields. This was achieved through the political used of different discourses, one of those completely new that brought the inhabitants of SMT around common concerns. This, I proposed, was expressed in a new way of politics –with the advent of a new kind of subjectivity- in which interests and concerns are shared, but also anxiety, unease and uncertainty. Even though there are some signs to discern a future panorama with place for the emergence and discussion of a ‚democracy of el pueblo‛.
The application of reporter gene assays for the detection of endocrine disruptors in sport supplements
Plotan, M. ; Elliot, C.T. ; Scippo, M.L. ; Müller, M. ; Antignac, J.P. ; Malone, E. ; Bovee, T.F.H. ; Mitchell, S. ; Connolly, L. - \ 2011
Analytica Chimica Acta 700 (2011)1-2. - ISSN 0003-2670 - p. 34 - 40.
dietary-supplements - anabolic-steroids - androgen receptor - sex-hormones - chemicals - estrogen - health - urine
The increasing availability and use of sports supplements is of concern as highlighted by a number of studies reporting endocrine disruptor contamination in such products. The health food supplement market, including sport supplements, is growing across the Developed World. Therefore, the need to ensure the quality and safety of sport supplements for the consumer is essential. The development and validation of two reporter gene assays coupled with solid phase sample preparation enabling the detection of estrogenic and androgenic constituents in sport supplements is reported. Both assays were shown to be of high sensitivity with the estrogen and androgen reporter gene assays having an EC50 of 0.01 ng mL-1 and 0.16 ng mL-1 respectively. The developed assays were applied in a survey of 63 sport supplements samples obtained across the Island of Ireland with an additional seven reference samples previously investigated using LC–MS/MS. Androgen and estrogen bio-activity was found in 71% of the investigated samples. Bio-activity profiling was further broken down into agonists, partial agonists and antagonists. Supplements (13) with the strongest estrogenic bio-activity were chosen for further investigation. LC–MS/MS analysis of these samples determined the presence of phytoestrogens in seven of them. Supplements (38) with androgen bio-activity were also selected for further investigation. Androgen agonist bio-activity was detected in 12 supplements, antagonistic bio-activity was detected in 16 and partial antagonistic bio-activity was detected in 10. A further group of supplements (7) did not present androgenic bio-activity when tested alone but enhanced the androgenic agonist bio-activity of dihydrotestosterone when combined. The developed assays offer advantages in detection of known, unknown and low-level mixtures of endocrine disruptors over existing analytical screening techniques. For the detection and identification of constituent hormonally active compounds the combination of biological and physio-chemical techniques is optimal.
Upgrading, downgrading and out-grading smallholders in the Vietnamese Pangasius value chain
Khiem, N.T. ; Bush, S.R. ; Coles, C. - \ 2011
In: Markets and Rural Poverty. Upgrading in Value Chains / Mitchell, J., Coles, C., London : Earthscan - ISBN 9781849713139 - p. 77 - 90.
Contributions of natural environments to physical activity: theory and evidence base
Vries, S. de; Claßen, T. ; Eigenheer-Hug, S.M. ; Korpela, K. ; Maas, J. ; Mitchell, R. ; Schantz, P. - \ 2011
In: Forests, trees and human health / Nilsson, K., Sangster, M., Gallis, C., Hartig, T., de Vries, S., Seeland, K., Schipperijn, J., Springer Science + Business Media - ISBN 9789048198054 - p. 205 - 243.
The idea that nearby nature stimulates people to be more physically active is quite popular. In this chapter the literature regarding the link between physical activity and the residential environment is scrutinized. More specifically, after introducing the main concepts and a theoretical framework the evidence regarding three categories of activity is examined: physical activity in general, walking and cycling (mainly by adults), and outdoor play by children. Overall activity is deemed important because of its link to total energy expenditure, and thereby health. However, the other two categories are more likely to be linked to green aspects of the environment. Also attention is paid to the possibility that activity undertaken in a natural environment is especially beneficial for one’s health. At the end of the chapter conclusions are summarized, directions for future research are proposed and policy recommendations are given, as far as possible given the current state of affairs.
Current estimates of goose population sizes in western Europe, a gap analysis and assessment of trends
Fox, A.D. ; Ebbinge, B.S. ; Mitchell, C. ; Heinicke, T. ; Aarvak, T. ; Colhoun, K. ; Clausen, P. ; Dereliev, S. ; Farago, S. ; Koffijberg, K. ; Kruckenberg, H. ; Loonen, M.J.J.E. ; Madsen, J. ; Mooij, J. ; Musil, P. ; Nilsson, L. ; Pihl, S. ; Jeugd, H. van der - \ 2010
Ornis Svecica 20 (2010). - ISSN 1102-6812 - p. 115 - 127.
We estimated the size of 30 defined populations of geese
wintering in the Western Palearctic (including five released
or reintroduced populations of three species).
Fourteen populations were accurately estimated from almost
full count coverage or robust sampling and ten were
well estimated based on more than 50% of their total being
counted. An estimated 5.03 million geese wintered
in January 2009, up on 3.10 million in January 1993.
Only two populations numbered less than 10,000 birds
(Scandinavian Lesser White-fronted Goose and Svalbard/
Greenland Light-bellied Brent Goose, the former
being critically small within restricted range). Eighteen
populations numbered 10,000–100,000, eight 100,000–
1,000,000 and the largest 1.2 million individuals. Of 21
populations with known longer term trends, 16 are showing
significant exponential increases, 4 are stable and one
declining. Amongst these same populations, five are declining
since the 1990s. Long term declines in productivity
were found in 7 out of 15 populations. Amongst most
of the 11 populations for which data exist, there were no
significant long-term trends in annual adult survival. Improved
monitoring, including demographic, is required
to retain populations in favorable conservation status.
|Europeanization of climate governance in metropolitan regions
Kern, K. - \ 2010
In: Regions and the Environment / Beauclair, A., Mitchell, E., Seaford, UK : Regional Studies Association - ISBN 9781897721384 - p. 108 - 109.
Effect of temperature and nutrients on the competition between free-floating Salvinia natans and submerged Elodea nuttallii in mesocosms
Netten, J.J.C. ; Arts, G.H.P. ; Gylstra, R. ; Nes, E.H. van; Scheffer, M. ; Roijackers, R.M.M. - \ 2010
Fundamental and Applied Limnology 177 (2010)2. - ISSN 1863-9135 - p. 125 - 132.
eichhornia-crassipes - molesta mitchell - plant-density - growth - macrophytes - climate - lakes - ecosystems - canadensis - vegetation
In many aquatic ecosystems, free-floating plants compete with submerged plants for nutrients and light. Being on top of the water surface free-floating plants are superior competitors for light. Submerged plants can take up nutrients from the sediment and the water column, hereby reducing these levels for free-floating plants. Global warming may change chances of successful species invasion and can alter species dominance. We studied the combined effects of nutrient loading and increased temperature on the competition between the potentially invasive free-floating Salvinia natans (L.) All. and the naturalized submerged Elodea nuttallii Planch. St. John by an outdoor mesocosm experiment under temperate climate conditions (The Netherlands) over a period of 71 days. The free-floating S. natans benefited from increased temperature and increased nutrient loading and limited the chances for the submerged E. nuttallii to take advantage of these changed conditions. S. natans substantially increased temperature in the top layer, while limiting the temperature increase below the mat. Our results suggest that with global warming, invasive free-floating plants might become more successful at the expense of submerged plants.
Relations between sensorial crispness and molecular mobility of model bread crust and its main components as measured by PTA, DSC and NMR
Nieuwenhuijzen, N.H. van; Tromp, R.H. ; Mitchell, J.R. ; Primo-Martin, C. ; Hamer, R.J. ; Vliet, T. van - \ 2010
Food Research International 43 (2010)1. - ISSN 0963-9969 - p. 342 - 349.
glass-transition temperature - wheat-starch - fracture-behavior - pulsed h-1-nmr - water-content - gluten - foods - state
Consumer appreciation of brittle cellular foods, like bread crusts, depends on textural properties such as crispness. This crispy character is lost above a certain water activity. It is not known what exactly is happening in these crusts when water enters. So is it unclear whether it is the change in the starch or the gluten that initiates the loss of crispness with ageing time. In this paper the effect of water on the glass transition of model bread crusts was studied using two complementary techniques: phase transition analysis (PTA) and temperature modulated differential scanning calorimetry (TMDSC). The mobility of water was studied with nuclear magnetic resonance (NMR). The results were compared with sensory data. Bread crusts prepared with different types of flour were tested to evaluate the effect of flour composition on the crispness of model crusts equilibrated at different relative humidities. In addition the single flour components starch and gluten were studied. Sensory crispness scores decreased with increasing aw from 0.55 upwards. At aw 0.70 sensory crispness was completely lost. Both DSC and PTA showed a transition point at an aw of 0.70-0.75. NMR gave a transition point in the mobility of the protons of water at aw 0.58. This supports the hypothesis that loss of crispness starts as a result of processes at a molecular level, before the macroscopic glass transition. This also suggests that the presence of water that is not directly attached to the solid matrix causes the loss of crispness at low aw. At higher aw increased mobility of the macromolecules will start to play a role. NMR experiments with the separate flour components indicate that the T2 transition point in starch samples occurs at a lower RH than for gluten. This could imply that starch loses crispness at lower aw than gluten. Increased mobility of small components and side chains might induce increased energy dissipation upon deformation of the material resulting in less available energy for fracture propagation and with that in a less crispy product.
How atmospheric N deposition affects peatland vegetation composition, production and Sphagnum N concentration: an analysis of 30 fertilization sturdies across the Northern Hemisphere
Limpens, J. ; Granath, G. ; Gunnarsson, U. ; Aerts, R. ; Bragazza, L. ; Breeuwer, A.J.G. ; Bubier, J. ; Berg, L. van den; Franchez, A.J. ; Gerdol, R. ; Heijmans, M.M.P.D. ; Hoosbeek, M.R. ; Hotes, S. ; Ilomets, M. ; Mitchell, E. ; Moore, T. ; Nilsson, M. ; Nordbakken, J.F. ; Paulissen, M.P.C.P. ; Risager, M. ; Rochefort, L. ; Rydin, H. ; Sheppard, L. ; Thormann, M. ; Tomassen, H. ; Williams, B. - \ 2009
In: Working Papers of the Finnish Forest Research Institute 128, Proceedings of the 6th International Symposium on Ecosystem Behaviour BIOGEOMON 2009, Helsinki, Finland, 29 June - 3 July 2009. - Vantaa, Finland : Finnish Forest Research Institute - ISBN 9789514021763 - p. 251 - 251.
Biodiversity conservation planning adapted to climate change
Geertsema, W. ; Opdam, P.F.M. ; Vos, C.C. ; Kramer, K. - \ 2008
In: Abstracts and panels of Resilience 2008. - - p. 109 - 109.
Current conservation planning defines targets for conservation sites that are based on historic references of vegetation types and local species occurrence or density (Margules et al. 1994). The long term effectiveness of such a static, site-oriented strategy is currently challenged by new scientific insight on ecosystem functioning (Gaston et al. 2006) and the unpredictability of the effects of increased perturbations caused by climate change (Mitchell and Hulme 1999). Therefore, a paradigm shift in biodiversity conservation planning is needed. Three main challenges are identified. Firstly, the exclusion of disturbances in current conservation practice ignores the nonequilibrium nature of ecosystems (Holling 1973). Disturbances are increasingly considered on the one hand the base of co-existence of species and therefore of biodiversity. On the other hand disturbances allow ecosystems to adapt to changed environmental conditions and are considered a source of renewal. Preventing disturbances to occur and restoring ecosystems to its original form, if an inadvertent disturbance did occur, results in a loss of biodiversity and adaptive capacity. Disturbances should not be perceived as undesirable, but be incorporated as an integral part of biodiversity conservation planning. Secondly, species differ in their sensitivity and response to different sources of disturbance. This is illustrated by the various responses to changing weather conditions due to climate change. The differences in the responses of species result in changing species composition of communities. Hence, the very base of current conservation policy that community types have high predictive capacity for the occurrence of target species, erodes away as climate change progresses. Instead of a focus on individual species as conservation targets for protected areas, the presence of functional diversity enabling differential responses to disturbances and enabling the continuation of ecosystem functioning should be the focus of biodiversity conservation planning. Thirdly, most existing reserves are too small to incorporate long term and large scale dynamics (Bengtsson et al. 2003). Population studies in fragmented ecosystem patterns on the landscape scale have shown dynamic patterns typical for metapopulations (Hanski & Gilpin 1991; Verboom et al. 2001; Vos et al. 2001), implying that the local occurrence of species is often unpredictable and largely dependent on characteristics of ecosystem networks at the regional scale level (Opdam & Wiens 2002; Opdam et al. 2003). Also the consequences of climate change on species ranges cannot be controlled or counteracted by local management actions. Thus the scale of the individual reserve is too small to sustain nature quality targets. Instead of local sites as the object of planning, a landscape and regional approach in biodiversity conservation planning is needed. Science has to play a key role in the paradigm shift. Science needs to provide evidence to societal partners about the effectiveness of dealing with ecosystems in a more adaptive way. Convincing cases, based on thorough science, of land use planning where biodiversity and ecosystems are considered in a more functional way are pivotal. Huge efforts are demanded before science can provide operational methods for goal setting, design and evaluation for regional planning. For example, a framework for the diagnosis of effect and response diversity should be developed. Ecosystems and ecosystem networks should be analysed for their key structures and processes and feedback mechanisms, based on such an analysis key functional groups are identified. Next the potential variation of functional groups needs to be explored and interpreted to generate a system of reference values for determining an operational framework for goal setting. We need to develop insight in the quantitative relation between the variation of functional groups, the adaptive capacity of ecosystems and ecosystem networks and the spatial characteristics. The challenge to science is not only to make this information quantitatively applicable in a spatial context, but science should also be more effective in transferring this knowledge into societal decision-making than it has been up to now. Implementing the paradigm shift is a societal learning process. Science should be part of that, and learn from practical applications just as well as practice is learning from science. A key issue in this learning process is how to deal with uncertainty. We will not be able to predict exact levels of adaptive capacity, because the nature, frequency and severity of disturbances that ecosystems will be faced with are unpredictable. Ecosystems are moving targets, with multiple potential futures that are uncertain and unpredictable (Holling and Meffe 1996). What we intend to realize with this approach is that we learn, in the end, to manage ecosystems and landscapes in such a way that they are adapted to the unpredictability and uncertainty that we face.
The changing landscape of Clara Bog: the history of an Irish raised bog
Crushell, P.H. ; Connolly, A. ; Schouten, M.G.C. ; Mitchell, F.J.G. - \ 2008
Irish Geography 41 (2008)1. - ISSN 0075-0778 - p. 89 - 111.
Clara Bog is one of the few raised bogs that has not been fully exploited in the Irish midlands and is a reminder of how the landscape of this region once appeared. This paper describes how the Clara Bog landscape has been changing since the commencement of the Holocene 11,500 years ago. Initially change was relatively slow as the bog naturally developed from its origins in an early Holocene lake, which became in-filled to form a fen circa 8000 years ago, before it continued to develop into an acid raised bog reaching its maximum extent by the beginning of the nineteenth century. Clara Bog has changed dramatically in the last 200 years due to human activity. Today less than 50% of its original bog surface remains. The changes in the bog during the historic past have been driven by population change, poverty, economic growth, construction of the Grand Canal, the building of roads, the need for fuel and farmland, nature conservation and tourism. The prehistoric development of the bog and land use in its hinterland was reconstructed from a detailed analysis of published archaeological records, palaeoecological studies and stratigraphical studies. Published maps and historical records have been vital in establishing a chronology for the changes that have occurred on Clara Bog since the beginning of the nineteenth century
A genome-wide functional investigation into the roles of receptor-like proteins in Arabidopsis
Guodong Wang, G. ; Ellendorff, U. ; Kemp, B. ; Mansfield, J.W. ; Forsyth, A. ; Mitchell, K. ; Bastas, K. ; Liu, C.M. ; Woods-Tör, A. ; Zipfel, C. ; Wit, P.J.G.M. de; Jones, J.D.G. ; Tör, M. ; Thomma, B.P.H.J. - \ 2008
Plant Physiology 147 (2008). - ISSN 0032-0889 - p. 503 - 517.
leucine-rich repeat - disease resistance genes - cladosporium-fulvum - pseudomonas-syringae - microbial pathogens - systemic resistance - flower development - plant-pathogen - kinase - thaliana
Receptor-like proteins (RLPs) are cell surface receptors that typically consist of an extracellular leucine-rich repeat domain, a transmembrane domain, and a short cytoplasmatic tail. In several plant species, RLPs have been found to play a role in disease resistance, such as the tomato (Solanum lycopersicum) Cf and Ve proteins and the apple (Malus domestica) HcrVf2 protein that mediate resistance against the fungal pathogens Cladosporium fulvum, Verticillium spp., and Venturia inaequalis, respectively. In addition, RLPs play a role in plant development; Arabidopsis (Arabidopsis thaliana) TOO MANY MOUTHS (TMM) regulates stomatal distribution, while Arabidopsis CLAVATA2 (CLV2) and its functional maize (Zea mays) ortholog FASCINATED EAR2 regulate meristem maintenance. In total, 57 RLP genes have been identified in the Arabidopsis genome and a genome-wide collection of T-DNA insertion lines was assembled. This collection was functionally analyzed with respect to plant growth and development and sensitivity to various stress responses, including susceptibility toward pathogens. A number of novel developmental phenotypes were revealed for our CLV2 and TMM insertion mutants. In addition, one AtRLP gene was found to mediate abscisic acid sensitivity and another AtRLP gene was found to influence nonhost resistance toward Pseudomonas syringae pv phaseolicola. This genome-wide collection of Arabidopsis RLP gene T-DNA insertion mutants provides a tool for future investigations into the biological roles of RLPs
Patterns of interaction specificity of fungus-growing termites and Termitomyces symbionts in South Africa
Aanen, D.K. ; Ros, V.I.D. ; Fine Licht, H.H. de; Mitchell, J. ; Beer, Z.W. de; Slippers, B. ; Rouland-Lefevre, C. ; Boomsma, J.J. - \ 2007
BMC Evolutionary Biology 7 (2007). - ISSN 1471-2148 - 11 p.
multiple sequence alignment - phylogenetic-relationships - evolutionary history - ants - macrotermitinae - isoptera - colonies - models - trees - comb
Background Termites of the subfamily Macrotermitinae live in a mutualistic symbiosis with basidiomycete fungi of the genus Termitomyces. Here, we explored interaction specificity in fungus-growing termites using samples from 101 colonies in South-Africa and Senegal, belonging to eight species divided over three genera. Knowledge of interaction specificity is important to test the hypothesis that inhabitants (symbionts) are taxonomically less diverse than 'exhabitants' (hosts) and to test the hypothesis that transmission mode is an important determinant for interaction specificity. Results Analysis of Molecular Variance among symbiont ITS sequences across termite hosts at three hierarchical levels showed that 47 % of the variation occurred between genera, 18 % between species, and the remaining 35 % between colonies within species. Different patterns of specificity were evident. High mutual specificity was found for the single Macrotermes species studied, as M. natalensis was associated with a single unique fungal haplotype. The three species of the genus Odontotermes showed low symbiont specificity: they were all associated with a genetically diverse set of fungal symbionts, but their fungal symbionts showed some host specificity, as none of the fungal haplotypes were shared between the studied Odontotermes species. Finally, bilaterally low specificity was found for the four tentatively recognized species of the genus Microtermes, which shared and apparently freely exchanged a common pool of divergent fungal symbionts. Conclusion Interaction specificity was high at the genus level and generally much lower at the species level. A comparison of the observed diversity among fungal symbionts with the diversity among termite hosts, indicated that the fungal symbiont does not follow the general pattern of an endosymbiont, as we found either similar diversity at both sides or higher diversity in the symbiont. Our results further challenge the hypothesis that transmission-mode is a general key-determinant of interaction specificity in fungus-growing termites.
Diploid apomicts of the Boechera holboelli complex display large scale chromosome substitutions and aberrant chromosomes
Kantama, L. ; Sharbel, T.F. ; Schranz, M.E. ; Mitchell-Olds, T. ; Vries, S.C. de; Jong, J.H.S.G.M. de - \ 2007
Proceedings of the National Academy of Sciences of the United States of America 104 (2007). - ISSN 0027-8424 - p. 14026 - 14031.
in-situ hybridization - gene-expression - pennisetum-squamulatum - cenchrus-ciliaris - arabis-drummondii - b-chromosome - brassicaceae - evolution - arabidopsis - apomixis
We conducted a cytogenetic study of sexual lines of Boechera stricta and Boechera holboellii (2n = 14) and seven diploid apomictic accessions of their interspecific hybrid Boechera divaricarpa and B. holboellii (2n = 14 or 15). By studying chromosome morphology, rDNA repeats, genome painting, male meiosis, pollen morphology, and flow-cytometry seed screens, we revealed an unexpected plethora of chromosome forms, pairing behavior, and hybrid composition in all apomictic lines. Genome painting demonstrated that the apomicts are alloploid with variable numbers of B. stricta and B. holboellii-like chromosomes. We assume that large-scale homeologous chromosome substitutions took place in the apomictic hybrids that resulted from recurrent diploid-polyploid transitions through restitutional meiosis and polyploicly-diploid transitions through reductional meiosis. A second peculiarity was the presence of a largely heterochromatic chromosome (Het) in all apomictic accessions (2n = 14 and 15) and an additional smaller chromosome (Den in the aneuploids (2n = 15). Both chromosomes share repetitive pericentromere repeats with those from the sexual B. stricta, suggesting that they originated from this species. Pairing and behavior at meiosis I of the Het share features with both Y and B chromosomes and suggest that the Del arose from a translocation event or homeologous recombination between a B. holboellii (or related taxon) and a B. stricta chromosome. Based on its presence exclusively in apomictic accessions, we propose that the Het chromosome plays a role in the genetic control of apomixis.
Reference material for radionuclides in sediment IAEA-384 (Fangataufa Lagoon sediment)
Povinec, P.P. ; Pham, M.K. ; Sanchez-Cabeza, J.A. ; Barci-Funel, G. ; Bojanowski, R. ; Boshkova, T. ; Burnett, W.C. ; Carvalho, F. ; Chapeyron, B. ; Cunha, I.L. ; Dahlgaard, H. ; Galabov, N. ; FiField, L.K. ; Gastaud, J. ; Geering, J.J. ; Gomez, I.F. ; Green, N. ; Hamilton, T. ; Ibanez, F.L. ; Ibn Majah, M. ; John, M. ; Kanisch, G. ; Kenna, T.C. ; Kloster, M. ; Korun, M. ; Liong Wee Kwong, L. ; Rosa, J. la; Lee, S.H. ; Levy-Palomo, I. ; Malatova, M. ; Maruo, Y. ; Mitchell, P. ; Murciano, I.V. ; Nelson, R. ; Nouredine, A. ; Oh, J.S. ; Origioni, B. ; Petit, G. le; Petterson, H.B.L. ; Reineking, A. ; Smedley, P.A. ; Suckow, A. ; Struijs, T.D.B. van der; Voors, P.I. ; Yoshimizu, K. ; Wyse, E. - \ 2007
Journal of Radioanalytical and Nuclear Chemistry 273 (2007)2. - ISSN 0236-5731 - p. 383 - 393.
certified reference material - pacific-ocean - irish sea - seawater - water - pu
A reference material designed for the determination of anthropogenic and natural radionuclides in sediment, IAEA-384 (Fangataufa Lagoon sediment), is described and the results of certification are presented. The material has been certified for 8 radionuclides (40K, 60Co, 155Eu, 230Th, 238U, 238Pu, 239+240Pu and 241Am). Information values are given for 12 radionuclides (90Sr, 137Cs, 210Pb (210Po), 226Ra, 228Ra, 232Th, 234U, 235U, 239Pu, 240Pu and 241Pu). Less reported radionuclides include 228Th, 236U, 239Np and 242Pu. The reference material may be used for quality management of radioanalytical laboratories engaged in the analysis of radionuclides in the environment, as well as for the development and validation of analytical methods and for training purposes. The material is available from IAEA in 100 g units.
Characterisation of BDPH1, a membrane localised receptor like protein involved in basal defence of Arabidopsis thaliana
Kemp, B. ; Mitchell, K. ; Forsyth, A. ; Çevik, V. ; Thomma, B. ; Holub, E. ; Mansfield, J. ; Tör, M. - \ 2007
In: Book of Abstracts XIII International Congress on Molecular Plant-Microbe Interactions, Sorrento, Italy, 21-27 July 2007. - - p. 205 - 205.
Asexual reproduction in a close relative of Arabidopsis: a genetic investigation of apomixis in Boechera ( Brassicaceae).
Schranz, M.E. ; Kantama, L. ; Jong, J.H.S.G.M. de; Mitchell-Olds, T. - \ 2006
New Phytologist 171 (2006)2. - ISSN 0028-646X - p. 425 - 438.
holboellii brassicaceae - dandelions taraxacum - molecular markers - arabis-drummondii - poa-pratensis - apomixis - apospory - evolution - populations - inheritance
Understanding apomixis (asexual reproduction through seeds) is of great interest to both plant breeders and evolutionary biologists. The genus Boechera is an excellent system for studying apomixis because of its close relationship to Arabidopsis, the occurrence of apomixis at the diploid level, and its potentially simple inheritance by transmission of a heterochromatic (Het) chromosome. ¿ Diploid sexual Boechera stricta and diploid apomictic Boechera divaricarpa (carrying a Het chromosome) were crossed. Flow cytometry, karyotype analysis, genomic in situ hybridization, pollen staining and seed-production measurements were used to analyse the parents and resulting F1, F2 and selected F3 and test-cross (TC) generations. ¿ The F1 plant was a low-fertility triploid that produced a swarm of aneuploid and polyploid F2 progeny. Two of the F2 plants were fertile near-tetraploids, and analysis of their F3 and TC progeny revealed that they were sexual and genomically stabilized. ¿ The apomictic phenotype was not transmitted by genetic crossing as a single dominant locus on the Het chromosome, suggesting a complex genetic control of apomixis that has implications for future genetic and evolutionary analyses in this group
|Problem Framing in Assessment Processes: the case of Biosafety.
Gupta, A. - \ 2006
In: Global Environmental Assessments: Information and Influence. / Mitchell, R.B., Clark, W.C., Cash, D., Dickson, N.M., Cambridge : MIT Press - ISBN 9780262633369 - p. 57 - 86.
Biogeographic distribution of polyploidy and B chromosomes in the apomictic Boechera holboellii complex
Sharbel, T.F. ; Mitchell-Olds, T. ; Dobes, C. ; Kantama, L. ; Jong, J.H.S.G.M. de - \ 2005
Cytogenetic and Genome Research 109 (2005)1-3. - ISSN 1424-8581 - p. 283 - 292.
arabis-holboellii - molecular systematics - natural-populations - rust infection - brassicaceae - evolution - plants - arabidopsis - mechanisms - apomixis
The Boechera holboellii complex comprises B. holboellii and B. drummondii, both of which can reproduce through sex or apomixis. Sexuality is associated with diploid individuals, whereas apomictic individuals are diploid or triploid and may additionally have B chromosomes. Using flow cytometry and karyotype analysis, we have shown that B chromosomes (a) occur in both diploid and triploid apomictic B. holboellii, (b) may occur in triploid B. drummondii, and (c) are dispensable for the plant. Both diploid and triploid karyotypes are found in multiple chloroplast haplotypes of both species, suggesting that triploid forms have originated multiple times during the evolution of this complex. B chromosome carriers are found in geographically and genetically distinct popu-lations, but it is unknown whether the extra chromosomes are shared by common descent (single origin) or have originated via introgressive hybridization and repeated transitions from diploidy to triploidy. Diploid plants containing the Bs reproduce apomictically, suggesting that the supernumerary elements are associated with apomixis. Finally, our analyses of pollen size and viability suggest that irregular chromosome segregation in some triploid lineages may lead to the generation of diploid individuals which carry the B chromosomes.
Ecosystem Service Supply and Vulnerability to Global Change in Europe
Schröter, D. ; Cramer, W. ; Leemans, R. ; Prentice, I.C. ; Araujo, M.B. ; Arnell, N.W. ; Bondeau, A. ; Brugmann, H. ; Carter, T.R. ; Gracia, C.A. ; Vega-Leinert, A.C. de la; Erhard, M. ; Ewert, F. ; Glendining, M. ; House, J.I. ; Kankaanpää, S. ; Klein, R.J.T. ; Lavorel, S. ; Lindner, M. ; Metzger, M.J. ; Meyer, J. ; Mitchell, T. ; Reginster, I. ; Rounsevell, M. ; Sabate, S. ; Stich, S. ; Smith, B. ; Smith, J. ; Smith, P. ; Sykes, M.T. ; Thonicke, K. ; Thuiller, W. ; Tuck, G. ; Zaehle, S. ; Zierl, B. - \ 2005
Science 310 (2005)5752. - ISSN 0036-8075 - p. 1333 - 1337.
climate-change - land-use - future scenarios - biodiversity
Global change will alter the supply of ecosystem services that are vital for human well-being. To investigate ecosystem service supply during the 21st century, we used a range of ecosystem models and scenarios of climate and land-use change to conduct a Europe-wide assessment. Large changes in climate and land use typically resulted in large changes in ecosystem service supply. Some of these trends may be positive (for example, increases in forest area and productivity) or offer opportunities (for example, "surplus land" for agricultural extensification and bioenergy production). However, many changes increase vulnerability as a result of a decreasing supply of ecosystem services (for example, declining soil fertility, declining water availability, increasing risk of forest fires), especially in the Mediterranean and mountain regions.
Advanced terrestrial ecosystem analysis and modelling (ATEAM)
Schröter, D. ; Acosta-Michlik, L. ; Arnell, A.W. ; Araújo, M.B. ; Badeck, F. ; Bakker, Martha ; Bondeau, A. ; Brugmann, H. ; Carter, T. ; Vega de la-Leinert, A.C. ; Erhard, M. ; Espineira, G.Z. ; Ewert, F. ; Fritsch, U. ; Friedlingstein, P. ; Glendining, M. ; Gracia, C.A. ; Hickler, T. ; House, J. ; Hulme, M. ; Kankaanpää, S. ; Klein, R.J.T. ; Krukenberg, B. ; Lavorel, S. ; Leemans, R. ; Lindner, M. ; Liski, J. ; Metzger, M.J. ; Meyer, J. ; Mitchell, T. ; Mohren, G.M.J. ; Morales, P. ; Moreno, J.M. ; Reginster, I. ; Reidsma, P. ; Rounsevell, M. ; Pla, E. ; Pluimers, J.C. ; Prentice, I.C. ; Pussinen, A. ; Sánchez, A. ; Sabaté, S. ; Sitch, S. ; Smith, B. ; Smith, P. ; Sykes, M.T. ; Thonicke, K. ; Thuiller, W. ; Tuck, G. ; Werf, G. van der; Vayreda, J. ; Wattenbach, M. ; Wilson, D.W. ; Woodward, F.I. ; Zaehle, S. ; Zierl, B. ; Zudin, S. ; Cramer, W. - \ 2004
Potsdam : Potsdam Institute for Climate Impact Research (PIK)
Is the aneuploid chromosome in an apomictic Boechera holboellii a genuine B chromosome?
Sharbel, T.F. ; Voigt, M.L. ; Mitchell-Olds, T. ; Kantama, L. ; Jong, J.H.S.G.M. de - \ 2004
Cytogenetic and Genome Research 106 (2004)2-4. - ISSN 1424-8581 - p. 173 - 183.
arabis-holboellii - evolutionary genetics - molecular systematics - natural-populations - rust infection - brassicaceae - apomixis - arabidopsis - plants - parthenogenesis
The Boechera holboellii complex comprises B. holboellii and B. drummondii, both of which can reproduce through sex or apomixis. Sexuality is associated with diploidy, whereas apomictic individuals can either be diploid, aneuploid or triploid. Aneuploid individuals are found in geographically and genetically distinct populations and contain a single extra chromosome. It is unknown whether the supernumerary chromosomes are shared by common descent (single origin) or have originated via introgressive hybridizations associated with the repeated transition from diploidy to triploidy. Diploid plants containing the extra chromosome(s) reproduce apomictically, suggesting that the supernumerary elements are associated with apomixis. In this study we compared flow cytometry data, chromosome morphology, and DNA sequences of sexual diploid and apomictic aneuploids in order to establish whether the extra chromosome fits the classical concept of a B chromosome. Karyotype analyses revealed that the supernumerary chromosome in the metaphase complement is heterochromatic and often smaller than the A chromosomes, and differs in length between apomictic plants from different populations. DNA sequence analyses furthermore demonstrated elevated levels of non-synonymous substitutions in one of the alleles, likely that on the aneuploid chromosome. Although the extra chromosome in apomictic Boechera does not go through normal reductional meiosis, in which it may get eliminated or accumulated by a B-chromosome-specific process, its variable size and heterochromatic nature does meet the remaining criteria for a genuine B chromosome in other species. Its prevalence and conserved genetic composition nonetheless implies that this chromosome, if truly a B, may be atypical with respect to its influence on its carriers. Copyright (C) 2004 S. Karger AG, Basel.
ATEAM (advanced Terrestrial Ecosystem Analysis and Modelling) final project report, EC project EVK2-2000-00075
Schröter, D. ; Acosta-Michlik, L. ; Arnell, A.W. ; Araujo, M.B. ; Badeck, F. ; Bakker, M. ; Bondeau, A. ; Bugmann, H. ; Carter, T. ; Vega-Leinert, A.C. de la; Erhard, M. ; Espineira, G.Z. ; Ewert, F. ; Friedlingstein, P. ; Fritsch, U. ; Glendining, M. ; Gracia, C.A. ; Hickler, T. ; House, J. ; Hulme, M. ; Klein, R.J.T. ; Krukenberg, B. ; Lavorel, S. ; Leemans, R. ; Lindner, M. ; Liski, J. ; Metzger, M.J. ; Meyer, J. ; Mitchell, T. ; Mohren, G.M.J. ; Morales, P. ; Moreno, J.M. ; Reginster, I. ; Reidsma, P. ; Rounsevell, M. ; Pluimers, J.C. ; Prentice, I.C. ; Pussinen, A. ; Sanchez, A. ; Sabaté, S. ; Sitch, S. ; Smith, B. ; Smith, J. ; Smith, P. ; Sykes, M.T. ; Thonicke, K. ; Thuiller, W. ; Tuck, G. ; Werf, W. van der; Vayreda, J. ; Wattenbach, M. ; Wilson, D.W. ; Woodward, F.I. ; Zaehle, S. ; Zierl, B. ; Zudin, S. ; Cramer, W. - \ 2004
Postdam : Potsdam Institute for Climate Impact Research (PIK) - 139 p.
Fitting of the beat pattern observed in NMR free-induction decay signals of concentrated carbohydrate-water solutions
Derbyshire, W. ; Bosch, M. van den; Dusschoten, D. van; MacNaughtan, W. ; Farhat, I.A. ; Hemminga, M.A. ; Mitchell, J.R. - \ 2004
Journal of Magnetic Resonance 168 (2004)2. - ISSN 1090-7807 - p. 278 - 283.
molecular mobility - transition - systems - glasses
A series of mathematical functions has been used to fit the proton free-induction decays (FIDs) of concentrated carbohydrate-water samples. For the solid protons, these functions included a sine function, as well as the Fourier transforms of single and multiple Pake functions multiplied by a Gaussian broadening. The NMR signal from the mobile protons is described by an exponential function. It is found that in most cases the sine function gives a satisfactory result and provides valuable information about the second moment M-2 and the ratio of solid to mobile protons (f(s)/f(m)). A good indication for using the sine function is the presence of a beat in the FID. For high temperatures this approach breaks down, and a biexponential fit is more appropriate. If a clear dipolar splitting is observable in the NMR spectra, the Pake function (or a multiple Pake fit) should be used. In this case information about M-2 and f(s)/f(m) can also be obtained. (C) 2004 Elsevier Inc. All rights reserved.
Effects of elevated CO2 and N deposition on CH4 emissions from European mires
Silvola, J. ; Saarnio, S. ; Foot, J. ; Sundh, I. ; Greenup, A. ; Heijmans, M.M.P.D. ; Ekberg, A. ; Mitchell, E.P. ; Breemen, N. van - \ 2003
Global Biogeochemical Cycles 17 (2003)2 - 1068. - ISSN 0886-6236 - p. 37 - 1-37-12.
atmospheric carbon-dioxide - methane emissions - boreal mire - raised co2 - northern peatlands - water-table - nitrogen deposition - bog vegetation - forest soils - temperature
 Methane fluxes were measured at five sites representing oligotrophic peatlands along a European transect. Five study plots were subjected to elevated CO2 concentration (560 ppm), and five plots to NH4NO3 (3 or 5 g N yr(-1)). The CH4 emissions from the control plots correlated in most cases with the soil temperatures. The depth of the water table, the pH, and the DOC, N and SO4 concentrations were only weakly correlated with the CH4 emissions. The elevated CO2 treatment gave nonsignificantly higher CH4 emissions at three sites and lower at two sites. The N treatment resulted in higher methane emissions at three sites (nonsignificant). At one site, the CH4 fluxes of the N-treatment plots were significantly lower than those of the control plots. These results were not in agreement with our hypotheses, nor with the results obtained in some earlier studies. However, the results are consistent with the results of the vegetation analyses, which showed no significant treatment effects on species relationships or biomass production.
Reduced hybrid cluster proteins (HCP) from Desulfovibrio desulfuricans ATCC 27774 and Desulfovibrio vulgaris (Hildenborough): X-ray structures at high resolution using synchrotron radiation
Aragao, D. ; Macedo, S. ; Mitchell, E.P. ; Romao, C.V. ; Liu, M.Y. ; Frazao, C. ; Saraiva, L.M. ; Xavier, A.V. ; LeGall, J. ; Dongen, W.M.A.M. van; Hagen, W.R. ; Teixeira, M. ; Carrondo, M.A. ; Lindley, P. - \ 2003
Journal of Biological Inorganic Chemistry 8 (2003). - ISSN 0949-8257 - p. 540 - 548.
electron-density maps - escherichia-coli - angstrom resolution - nitrite reductase - sulfite reductase - prismane protein - identification - spectroscopy - refinement - errors
The hybrid cluster proteins from the sulfate reducing bacteria Desulfovibrio desulfuricans ATCC 27774 (Dd) and Desulfovibrio vulgaris strain Hildenborough(Dv) have been isolated and crystallized anaerobically. In each case, the protein has been reduced with dithionite and the crystal structure of the reduced form elucidated using X-ray synchrotron radiation techniques at 1.25 Angstrom and 1.55 Angstrom resolution for Dd and Dv, respectively. Although the overall structures of the proteins are unchanged upon reduction, there are significant changes at the hybrid cluster centres. These include significant movements in the position of the iron atom linked to the persulfide moiety in the oxidized as-isolated proteins and the sulfur atom of the persulfide itself. The nature of these changes is described and the implications with respect to the function of hybrid cluster proteins are discussed.
Regulation of floral scent production in petunia revealed by targeted metabolomics
Verdonk, J.C. ; Vos, C.H. de; Verhoeven, H.A. ; Haring, M.A. ; Tunen, A.J. van; Schuurink, R.C. - \ 2003
Phytochemistry 62 (2003). - ISSN 0031-9422 - p. 997 - 1008.
solid-phase microextraction - snapdragon flowers - linalool synthase - rosa-hybrida - in-situ - emission - volatiles - biosynthesis - expression - gene
Petunia hybrida line W115 (Mitchell) has large white flowers that produce a pleasant fragrance. By applying solid phase micro extraction (SPME) techniques coupled to GC-MS analysis, volatile emission was monitored in vivo using a targeted metabolomics approach. Mature flowers released predominantly benzenoid compounds of which benzaldehyde, phenylacetaldehyde, methylbenzoate, phenylethylalcohol, iso-eugenol and benzylbenzoate were most abundant. This emission had a circadian rhythm reaching its maximum at dusk. During petal limb expansion two sesquiterpenes were emitted by the petunia flowers, tentatively identified as germacrene D and cadina-3,9-diene. In vitro analysis showed that the petal limbs and stigma were the main producers of the benzenoids and sesquiterpenes, respectively. Moreover, comparison of in vivo and in vitro analysis indicated that volatiles were not stored during periods of low emission but rather were synthesized de novo. DNA-microarray analysis revealed that genes of the pathways leading to the production of volatile benzenoids were upregulated late during the day, preceding the increase of volatile emission. RNA-gel blot analyses confirmed that the levels of phenylalanine ammonia lyase (PAL) and S-adenosyl methionine (SAM) synthase transcripts increased towards the evening. Our results suggest that the circadian production of volatile benzenoids in petunia W115 is, at least partly, regulated at the transcript level.
Conolly, A. ; Kelly, L. ; Lamers, L. ; Mitchell, F.J.G. ; Schaaf, S. van der; Schouten, M.G.C. ; Streefkerk, J.G. ; Wirdum, G. van - \ 2002
In: Conservation and restoration of raised bogs: geological, hydrological and ecological studies / Schouten, M.G.C., Dublin : Dept. of the Env. and Local Government; Staatsbosbeheer - ISBN 9780755715596 - p. 170 - 185.
Effects of elevated CO2 and drought on wheat : testing crop simulation models for different experimental and climatic conditions
Ewert, F. ; Rodriguez, D. ; Jamieson, P. ; Semenov, M.A. ; Mitchell, R.A.C. ; Goudriaan, J. ; Porter, J.R. ; Kimball, B.A. ; Pinter, P.J. ; Manderscheid, R. ; Weigel, H.J. ; Fangmeier, A. ; Fereres, E. ; Villalobos, F. - \ 2002
Agriculture, Ecosystems and Environment 93 (2002). - ISSN 0167-8809 - p. 249 - 266.
Effects of increasing carbon dioxide concentration [CO2] on wheat vary depending on water supply and climatic conditions, which are difficult to estimate. Crop simulation models are often used to predict the impact of global atmospheric changes on food production. However, models have rarely been tested for effects on crops of [CO2] and drought for different climatic conditions due to limited data available from field experiments. Simulations of the effects of elevated [CO2] and drought on spring wheat (Triticum aestivum L.) from three crop simulation models (LINTULCC2, AFRCWHEAT2, Sirius), which differ in structure and mechanistic detail, were compared with observations. These were from 2 years of free-air carbon dioxide enrichment (FACE) experiments in Maricopa, Arizona and 2 years of standardised (in crop management and soil conditions) open-top chamber (OTC) experiments in Braunschweig and Giessen, Germany. In a simulation exercise, models were used to assess the possible impact of increased [CO2] on wheat yields measured between 1987 and 1999 at one farm site in the drought prone region of Andalucia, south Spain. The models simulated well final biomass (BM), grain yield (GY), cumulative evapotranspiration (ET) and water use efficiency (WUE) of wheat grown in the FACE experiments but simulations were unsatisfactory for OTC experiments. Radiation use efficiency (RUE) and yield responses to [CO2] and drought were on average higher in OTC than in FACE experiments. However, there was large variation among OTC experiments. Plant growth in OTCs was probably modified by several factors related to plot size, the use (or not use) of border plants, airflow pattern, modification of radiation balance and/or restriction of rooting volume that were not included in the models. Variation in farm yields in south Spain was partly explained by the models, but sources of unexplained yield variation could not be identified and were most likely related to effects of pests and diseases that were not included in the models. Simulated GY in south Spain increased in the range between 30 and 65 ue to doubling [CO2]. The simulated increase was larger when a [CO2]xdrought interaction was assumed (LINTULCC2, AFRCWHEAT2) than when it was not (Sirius). It was concluded that crop simulation models are able to reproduce wheat growth and yield for different [CO2] and drought treatments in a field environment. However, there is still uncertainty about the combined effects of [CO2] and drought including the timing of drought stress and about relationships that determine yield variation at farm and larger scales that require further investigation including model testing.
|Periphyton boosts production in pond aquaculture systems
Azim, E.A. ; Verdegem, M.C.J. ; Wahab, M.A. ; Dam, A.A. van; Beveridge, M.C.M. - \ 2001
World Aquaculture 32 (2001). - ISSN 1041-5602 - p. 57 - 61.
Silver perch (Bidyanus bidyanus, Mitchell) of 65 g average weight were reared at high density under controlled conditions on diets containing 24.8nd 40.6␙rotein. Diets were fed at 2␘r 4␘f the fish biomass day1. Both protein concentrations and feeding level of the diet influenced growth and proximate composition of the fish at the end of the 50-day growth trial. Energy requirement for maintenance for these fish was found to be 77 cal BW0.8 and for each unit of energy retained 3.78 cal BW0.8 needed to be supplied, and for each gram of protein retained per metabolic body weight 5.04 g were required. The results indicate that it is possible to obtain the same weight increment when feeding a 24.8␙rotein diet at a level of 4␋ody weight day1 as compared with only 2␋ody weight day1 of a 40.6␙rotein diet. This study indicates that the nutritional requirements for early grow-out are similar to those found in a previous study with juvenile silver perch and adds information concerning the required relationships between dietary amino acids. The results provide information required for further refinement of nutrition for this species
The sustainable agriculture farming system project in California's Sacramento Valley
Poudel, D.D. ; Ferris, H. ; Klonsky, K. ; Horwath, K. ; Scow, K.M. ; Bruggen, A.H.C. van; Lanini, W.T. ; Mitchell, J.P. ; Temple, S.R. - \ 2001
Outlook on Agriculture 30 (2001). - ISSN 0030-7270 - p. 109 - 116.
Can testate amoebae (protozoa) and other micro-organisms help to overcome biogeographic bias in large scale global change research?
Mitchell, E.A.D. ; Gilbert, D. ; Butler, A. ; Grosvernier, P. ; Albinsson, C. ; Rydin, H. ; Heijmans, M.M.P.D. ; Hoosbeek, M.R. ; Greenup, A. ; Foot, J. ; Saarinen, T. ; Vasander, H. - \ 2001
In: Global Change and Protected Areas / Visconti, G., - p. 301 - 310.
klimaatverandering - kooldioxide - vegetatie - micro-organismen - climatic change - carbon dioxide - vegetation - microorganisms
Raised atmospheric CO2 levels and increased N deposition cause shifts in plant species composition and production in Sphagnum bogs
Berendse, F. ; Breemen, N. van; Rydin, H. ; Buttler, A. ; Heijmans, M. ; Hoosbeek, M.R. ; Lee, J.A. ; Mitchell, E. ; Saarinen, T. ; Vasander, H. ; Wallen, B. - \ 2001
Global Change Biology 7 (2001). - ISSN 1354-1013 - p. 591 - 598.
broeikaseffect - emissie - kooldioxide - nitraten - veenplanten - greenhouse effect - emission - carbon dioxide - nitrates - bog plants
Part of the missing sink in the global CO2 budget has been attributed to the positive effects of CO2 fertilization and N deposition on carbon sequestration in Northern Hemisphere terrestrial ecosystems. The genus Sphagnum is one of the most important groups of plant species sequestrating carbon in temperate and northern bog ecosystems, because of the low decomposability of the dead material it produces. The effects of raised CO2 and increased atmospheric N deposition on growth of Sphagnum and other plants were studied in bogs at four sites across Western Europe. Contrary to expectations, elevated CO2 did not significantly affect Sphagnum biomass growth. Increased N deposition reduced Sphagnum mass growth, because it increased the cover of vascular plants and the tall moss Polytrichum strictum. Such changes in plant species composition may decrease carbon sequestration in Sphagnum-dominated bog ecosystems
|Effects on elevated CO2 and N deposition on CH4 emissions from European bogs
Saarnio, S. ; Silvola, J. ; Foot, J.P. ; Sundh, I. ; Greenup, A. ; Heijmans, M. ; Joabsson, A. ; Mitchell, E. ; Breemen, N. van - \ 2000
In: Sustaining Our Peatlands : 11th International Peat Congress, Canada 2000 / Rochefort, L., Daigle, J.Y., Canada : Gerry Hood - ISBN 9789519774442 - p. 1088 - 1088.
|Testate amoebae (protozoa) and other micro-organisms in sphagnum peatlands : biogeography, ecology and effect of elevated CO2
Mitchell, E.A.D. ; Gilbert, D. ; Buttler, A. ; Grosvernier, P. ; Albinsson, C. ; Rydin, H. ; Heijmans, M.M.P.D. ; Hoosbeek, M.R. ; Greenup, A. ; Foot, J.P. ; Saarinen, T. ; Vasander, H. ; Gobat, J.M. - \ 2000
In: Sustaining Our Peatlands : 11th International Peat Congress, Canada 2000 / Rochefort, L., Daigle, J.Y., Canada : Gerry Hood - ISBN 9789519774442 - p. 1087 - 1087.
|Effects of elevated CO2 and N deposition on bog vegetation dynamics
Hoosbeek, M.R. ; Breemen, N. van; Vasander, H. ; Saarinen, T. ; Silvola, J. ; Saarnio, S. ; Grosvernier, P. ; Mitchell, E. ; Berendse, F. ; Heijmans, M. ; Wallen, B. ; Rydin, H. ; Lee, J.A. ; Foot, J. - \ 2000
In: Core Research for Evolution Science and Technology : Face 2000, Japan 2000 - p. 19 - 19.
|Modeling the effects of elevated CO2 and N on the biogeochemistry of European bogs
Hoosbeek, M.R. ; Berendse, F. ; Foot, J.P. ; Greenup, A. ; Grosvernier, P. ; Mitchell, E.A.D. ; Rydin, H. ; Saarinen, T. ; Saarnio, S. ; Wallen, B. - \ 2000
In: Sustaining Our Peatlands : 11th International Peat Congress, Canada 2000 / Rochefort, L., Daigle, J.Y., Canada : Gerry Hood - ISBN 9789519774442 - p. 1086 - 1086.
|High N deposition affects competition between sphagnum and other bog plant species
Heijmans, M.M.P.D. ; Berendse, F. ; Breemen, N. van; Rydin, H. ; Buttler, A. ; Hoosbeek, M.R. ; Lee, J.A. ; Mitchell, E.A.D. ; Saarnio, S. ; Vasander, H. ; Wallen, B. - \ 2000
In: Sustaining Our Peatlands : 11th International Peat Congress, Canada 2000 / Rochefort, L., Daigle, J.Y., Canada : Gerry Hood - ISBN 9789519774442 - p. 1085 - 1085.
Relationships among testate amoebae (Protozoa), vegetation and water chemistry in five Sphagnum-dominated peatlands in Europe
Mitchell, E.A.D. ; Buttler, A. ; Grosvernier, P. ; Rydin, H. ; Albinsson, C. ; Greenup, A.L. ; Heijmans, M.M.P.D. ; Hoosbeek, M.R. ; Saarinen, T. - \ 2000
New Phytologist 145 (2000). - ISSN 0028-646X - p. 95 - 106.
turf - hoogveengronden - veengronden - grondanalyse - vegetatie - amoeba - grondwater - peat - bog soils - peat soils - soil analysis - vegetation - amoeba - groundwater
To study the relationships between groups of organisms and the degree to which these relationships are consistent across major climatic gradients, we analysed the testate amoeba (Protozoa) communities, vegetation and water chemistry of one peatland in five countries: Switzerland, The Netherlands, Great Britain, Sweden and Finland, as part of the BERI (Bog Ecosystem Research Initiative) project. The relationships between the different data sets and subsets were investigated by means of detrended correspondence analysis, canonical correspondence analysis and Mantel permutation tests. The comparison of data on vegetation and testate amoebae showed that inter-site differences are more pronounced for the vegetation than for the testate amoebae species assemblage. Testate amoebae are a useful tool in multi-site studies and in environmental monitoring of peatlands because: (1) the number of species in Sphagnum-dominated peatlands is much higher than for mosses or vascular plants; (2) most peatland species are cosmopolitan in their distributions and therefore less affected than plants by biogeographical distribution patterns, thus differences in testate amoeba assemblages can be interpreted primarily in terms of ecology; (3) they are closely related to the ecological characteristics of the exact spot where they live, therefore they can be used to analyse small-scale gradients that play a major role in the functioning of peatland ecosystems. This study revealed the existence of small-scale vertical gradients within the vegetation and life-form niche separation in response to water chemistry. The deep-rooted plants such as Carex spp. and Eriophorum spp. are related to the chemistry of water sampled at or near the ground water table, whereas the mosses are not. Testate amoebae were shown to be ecologically more closely related to the chemistry of water sampled at or near the water table level and to the mosses than to the deep-rooted plants.
|Microtus oeconomus (Pallas, 1776)
Apeldoorn, R.C. van - \ 1999
In: The atlas of European mammals / Mitchell-Jones, A.J., Amori, G., Bogdanowicz, W., Krystufek, B., Reijnders, P.J.H., Spitzenberger, F., Stubbe, M., Thissen, J.B.M., Vohralik, V., Zima, J., - p. 244 - 245.
|The atlas of European mammals
Mitchell-Jones, A.J. ; Amori, G. ; Bogdanowicz, W. ; Krystufek, B. ; Reijnders, P.J.H. ; Spitzenberger, F. ; Stubbe, M. ; Thissen, J.B.M. ; Vohralik, V. ; Zima, J. - \ 1999
London : Poyser (Poyser natural history ) - ISBN 9780856611308 - 484
zoogdieren - soorten - zoögeografie - populatiedynamica - distributie - populatiedichtheid - bescherming - kaarten - europa - mammals - species - zoogeography - population dynamics - distribution - population density - protection - maps - europe
Photosynthetic responses in spring wheat grown under elevated CO2 concentrations and stress conditions in the European, multiple-site experiment 'ESPACE-wheat'
Mitchell, R.A.C. ; Black, C.R. ; Burkart, S. ; Burke, J.I. ; Donnelly, A. ; Temmerman, L. de; Fangmeier, A. ; Mulholland, B.J. ; Theobald, J.C. ; Oijen, M. van - \ 1999
European Journal of Agronomy 10 (1999)3-4. - ISSN 1161-0301 - p. 205 - 214.
Spring wheat cv. Minaret crop stands were grown under ambient and elevated CO2 concentrations at seven sites in Germany, Ireland, the UK, Belgium and the Netherlands. Six of the sites used open-top chambers and one used a controlled environment mimicking field conditions. The effect of elevated CO2 for a range of N application regimes, O3 concentrations, and growth temperatures on flag leaf photosynthesis was studied. Before anthesis, flag leaf photosynthesis was stimulated about 50% by 650 compared with 350 μmol mol-1 CO2 at all sites, regardless of other treatments. Furthermore, there was no evidence of a decrease in photosynthetic capacity of flag leaves due to growth at elevated CO2 before anthesis, even for low N treatments. However, photosynthetic capacity, particularly carboxylation capacity, of flag leaves was usually decreased by growth at elevated CO2 after anthesis, especially in low N treatments. Acclimation of photosynthesis to elevated CO2 therefore appears to occur only slowly, consistent with a response to changes in sink-source relationships, rather than a direct response. Effect of elevated CO2 on stomatal conductance was much more variable between sites and treatments, but on average was decreased by ~ 10% at 650 compared with 350 μmol mol-1 CO2. Carboxylation capacity of flag leaves was decreased by growth at elevated O3 both before and after anthesis, regardless of CO2 concentration.
|Inter and intraspecific variation in composition of herbivore-induced synomones that attract predatory mites
Takabayashi, J. ; Dicke, M. ; Posthumus, M.A. ; Takahashi, S. - \ 1999
In: Acarology IX, Proceedings 9th International Congress of Acarology / Needham, G.R., Mitchell, R., Horn, D.J., Welbourn, W.C., Columbus Ohio : Ohio Biological Survey - p. 239 - 244.
Effects on nutrients and on grain quality in spring wheat crops grown under elevated CO2 concentrations and stress conditions in the European, multiple-site experiment 'ESPACE-wheat'
Fangmeier, A. ; Temmerman, L. de; Mortensen, L. ; Kemp, K. ; Burke, J. ; Mitchell, J.R.A.C. ; Oijen, M. van; Weigel, H.J. - \ 1999
European Journal of Agronomy 10 (1999)3-4. - ISSN 1161-0301 - p. 215 - 229.
Nutrient element concentrations and grain quality were assessed in spring wheat grown under elevated CO2 concentrations and contrasting levels of tropospheric ozone at different nitrogen supply rates at several European sites. Carbon dioxide enrichment proved to affect nutrient concentrations in a complex manner. In green leaves, all elements (with exception of phosphorus and iron) decreased. In contrast, effects on the element composition of grains were restricted to reductions in nitrogen, calcium, sulphur and iron. Ozone exposure resulted in no significant effects on nutrient element concentrations in different tissues in the overall analysis. The nitrogen demand of green tissues was reduced due to CO2 enrichment as shown by reductions in the critical leaf nitrogen concentration and also enhanced nitrogen use efficiency. Reductions in the content of ribulose-bisphosphate carboxylase/oxygenase and repression of the photorespiratory pathway and reduced nitrogen allocation to enzymes driving the photosynthetic carbon oxidation cycle were chiefly responsible for this effect. Thus, nitrogen acquisition by the crop did not match carbon acquisition under CO2 enrichment. Since crop nitrogen uptake from the soil was already completed at anthesis, nitrogen allocated to the grain after anthesis originated from vegetative pools - causing grain nitrogen concentrations to decrease under CO2 enrichment (on average by 15% when CO2 concentrations increased from 360 to 680 μmol mol-1). Correspondingly, grain quality was reduced by CO2 enrichment. The Zeleny value, Hagberg value and dry/wet gluten content decreased significantly with increasing [CO2]. Despite the beneficial impact of CO2 enrichment on growth and yield of C3 cereal crops, declines in flour quality due to reduced nitrogen content are likely in a future, [CO2]-rich world.