Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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    Effect of exogenous enzymes (phytase and xylanase) supplementation on nutrient digestibility and growth performance of Nile tilapia (Oreochromis niloticus) fed different quality diets
    Maas, Roel M. ; Verdegem, Marc C.J. ; Stevens, Theodor L. ; Schrama, Johan W. - \ 2020
    Aquaculture 529 (2020). - ISSN 0044-8486
    Diet formulation - Feed additives - Fibre - Non-starch polysaccharides - Phytate

    The use of plant by-products in aqua-feeds contributes to improving the sustainability of aquaculture, but also leads to increased levels of undesirable non-starch polysaccharides (NSP) and phytate. NSP-degrading enzymes (i.e. xylanase) and phytase can be used as a tool to deal with NSP and phytate. A feeding trial was conducted to test whether the effects of phytase and xylanase supplementation on growth performance and nutrient digestibility in Nile tilapia are dependent on diet quality. Two diets were formulated, a control quality (CQ diet; 36% protein and 17% NSP) and a low quality diet (LQ diet; 32% protein and 30% NSP). The difference in diet quality was created by using higher levels of wheat bran, rapeseed meal, sunflower meal, rice bran and wheat dried distiller's grain with solubles in the LQ diet. Both diets had the following enzyme treatments: 1) no enzymes, 2) phytase, and 3) phytase and xylanase. Phytase (Buttiauxella sp.) was supplemented at ca. 660 FTU/kg and xylanase at ca. 6596 U/kg. In total, 18 tanks (6 treatments, 3 replicates per treatment) were used with 30 fish each (mean initial body weight 39 g). Fish were restrictively fed at 80% of expected satiation for 42 days, by hand twice daily. Growth was determined by batch weighing of the fish at the start and at the end of the trial. Faeces were collected non-invasively using settling units in order to determine the nutrient digestibility, using yttrium as an inert marker. Fish fed the LQ diet had lower growth (1.35 g/d vs. 1.52 g/d) and nutrient digestibility (except for calcium and ash), compared to the CQ diet (P <.05). Phytase improved the digestibility of dry matter, total carbohydrates, NSP, energy, ash, phosphorus and calcium (P <.01) Phytase improved growth (g/d) by ca. 7% and phosphorus availability by ca. 29%. The improvement in growth with phytase was comparable between the two diets, improving the FCR from 1.04 to 0.97 and from 1.17 to 1.10 for the CQ and LQ diet, respectively. Xylanase supplementation, on top of phytase, did not enhance growth (P >.05). Xylanase improved digestibility of dry matter, energy, total carbohydrates and NSP (from 29.7% to 36.6%) of the LQ diet, but not of the CQ diet (interaction; P <.05). In conclusion, the effect of phytase on improved nutrient digestibility and performance was independent of diet quality, whereas the effect of xylanase was dependent on diet quality.

    Beneficial health effects of chitin and chitosan
    Dong, Liyou ; Wichers, H.J. ; Govers, C.C.F.M. - \ 2020
    In: Chitin and Chitosan / van den Broek, Lambertus A.M., Boeriu, Carmen G., Stevens, Christian V., John Wiley and Sons (Wiley Series in Renewable Research ) - ISBN 9781119450436 - p. 145 - 164.
    Chitin and chitosan have been recognised for their beneficial health effects since the 1980s. Over the past few decades, numerous studies and several clinical trials have been performed which demonstrated that these compounds can reduce body weight and cardiovascular disease (CVD), improve wound healing, but can also modulate the immune system and demonstrate antifungal and antibacterial activity. In particular, weight reduction and improvement of cardiovascular status are interesting targets as the prevalence of obesity and CVD are increasing. Both diseases are associated with various pathological disorders, including diabetes and hypertension and put a strain on healthcare costs and capacity. In general, lifestyle‐based interventions such as the oral intake of chitin and/or chitosan are becoming increasingly popular as these are easily integrated into current treatments and improve the self‐assertiveness of patients. Of interest, but beyond the scope of this chapter, is the use of chitin‐glucans as supplements in cosmetics. Several studies have demonstrated that chitin‐glucan reduced wrinkling and skin‐ageing, suggesting an interaction between the chitin‐glucan and cells of the epidermis. Although these effects may not be attributed to chitin alone, this does demonstrate the strong biological potential of chitin on cells of the human body. In this chapter, scientific literature has been reviewed that demonstrated the beneficial health effects of chitin and chitosan from an immunomodulatory point‐of‐view. First, we provide an overview of in vitro studies that offer in‐depth mechanistic insights, followed by describing preclinical animal studies. Finally, we list various human intervention trials that most clearly demonstrate the beneficial health effects of chitin and chitosan. Furthermore, we purposely discriminate between data on chitin and chitosan as they are chemically distinct and therefore possibly demonstrate unique effects on health
    The FLUXNET2015 dataset and the ONEFlux processing pipeline for eddy covariance data
    Pastorello, Gilberto ; Trotta, Carlo ; Canfora, Eleonora ; Chu, Housen ; Christianson, Danielle ; Cheah, You Wei ; Poindexter, Cristina ; Chen, Jiquan ; Elbashandy, Abdelrahman ; Humphrey, Marty ; Isaac, Peter ; Polidori, Diego ; Ribeca, Alessio ; Ingen, Catharine van; Zhang, Leiming ; Amiro, Brian ; Ammann, Christof ; Arain, M.A. ; Ardö, Jonas ; Arkebauer, Timothy ; Arndt, Stefan K. ; Arriga, Nicola ; Aubinet, Marc ; Aurela, Mika ; Baldocchi, Dennis ; Barr, Alan ; Beamesderfer, Eric ; Marchesini, Luca Belelli ; Bergeron, Onil ; Beringer, Jason ; Bernhofer, Christian ; Berveiller, Daniel ; Billesbach, Dave ; Black, Thomas Andrew ; Blanken, Peter D. ; Bohrer, Gil ; Boike, Julia ; Bolstad, Paul V. ; Bonal, Damien ; Bonnefond, Jean Marc ; Bowling, David R. ; Bracho, Rosvel ; Brodeur, Jason ; Brümmer, Christian ; Buchmann, Nina ; Burban, Benoit ; Burns, Sean P. ; Buysse, Pauline ; Cale, Peter ; Cavagna, Mauro ; Cellier, Pierre ; Chen, Shiping ; Chini, Isaac ; Christensen, Torben R. ; Cleverly, James ; Collalti, Alessio ; Consalvo, Claudia ; Cook, Bruce D. ; Cook, David ; Coursolle, Carole ; Cremonese, Edoardo ; Curtis, Peter S. ; Andrea, Ettore D'; Rocha, Humberto da; Dai, Xiaoqin ; Davis, Kenneth J. ; Cinti, Bruno De; Grandcourt, Agnes de; Ligne, Anne De; Oliveira, Raimundo C. De; Delpierre, Nicolas ; Desai, Ankur R. ; Bella, Carlos Marcelo Di; Tommasi, Paul di; Dolman, Han ; Domingo, Francisco ; Dong, Gang ; Dore, Sabina ; Duce, Pierpaolo ; Dufrêne, Eric ; Dunn, Allison ; Dušek, Jiří ; Eamus, Derek ; Eichelmann, Uwe ; ElKhidir, Hatim Abdalla M. ; Eugster, Werner ; Ewenz, Cacilia M. ; Ewers, Brent ; Famulari, Daniela ; Fares, Silvano ; Feigenwinter, Iris ; Feitz, Andrew ; Fensholt, Rasmus ; Filippa, Gianluca ; Fischer, Marc ; Frank, John ; Galvagno, Marta ; Gharun, Mana ; Gianelle, Damiano ; Gielen, Bert ; Gioli, Beniamino ; Gitelson, Anatoly ; Goded, Ignacio ; Goeckede, Mathias ; Goldstein, Allen H. ; Gough, Christopher M. ; Goulden, Michael L. ; Graf, Alexander ; Griebel, Anne ; Gruening, Carsten ; Grünwald, Thomas ; Hammerle, Albin ; Han, Shijie ; Han, Xingguo ; Hansen, Birger Ulf ; Hanson, Chad ; Hatakka, Juha ; He, Yongtao ; Hehn, Markus ; Heinesch, Bernard ; Hinko-Najera, Nina ; Hörtnagl, Lukas ; Hutley, Lindsay ; Ibrom, Andreas ; Ikawa, Hiroki ; Jackowicz-Korczynski, Marcin ; Janouš, Dalibor ; Jans, Wilma ; Jassal, Rachhpal ; Jiang, Shicheng ; Kato, Tomomichi ; Khomik, Myroslava ; Klatt, Janina ; Knohl, Alexander ; Knox, Sara ; Kobayashi, Hideki ; Koerber, Georgia ; Kolle, Olaf ; Kosugi, Yoshiko ; Kotani, Ayumi ; Kowalski, Andrew ; Kruijt, Bart ; Kurbatova, Julia ; Kutsch, Werner L. ; Kwon, Hyojung ; Launiainen, Samuli ; Laurila, Tuomas ; Law, Bev ; Leuning, Ray ; Li, Yingnian ; Liddell, Michael ; Limousin, Jean Marc ; Lion, Marryanna ; Liska, Adam J. ; Lohila, Annalea ; López-Ballesteros, Ana ; López-Blanco, Efrén ; Loubet, Benjamin ; Loustau, Denis ; Lucas-Moffat, Antje ; Lüers, Johannes ; Ma, Siyan ; Macfarlane, Craig ; Magliulo, Vincenzo ; Maier, Regine ; Mammarella, Ivan ; Manca, Giovanni ; Marcolla, Barbara ; Margolis, Hank A. ; Marras, Serena ; Massman, William ; Mastepanov, Mikhail ; Matamala, Roser ; Matthes, Jaclyn Hatala ; Mazzenga, Francesco ; McCaughey, Harry ; McHugh, Ian ; McMillan, Andrew M.S. ; Merbold, Lutz ; Meyer, Wayne ; Meyers, Tilden ; Miller, Scott D. ; Minerbi, Stefano ; Moderow, Uta ; Monson, Russell K. ; Montagnani, Leonardo ; Moore, Caitlin E. ; Moors, Eddy ; Moreaux, Virginie ; Moureaux, Christine ; Munger, J.W. ; Nakai, Taro ; Neirynck, Johan ; Nesic, Zoran ; Nicolini, Giacomo ; Noormets, Asko ; Northwood, Matthew ; Nosetto, Marcelo ; Nouvellon, Yann ; Novick, Kimberly ; Oechel, Walter ; Olesen, Jørgen Eivind ; Ourcival, Jean Marc ; Papuga, Shirley A. ; Parmentier, Frans Jan ; Paul-Limoges, Eugenie ; Pavelka, Marian ; Peichl, Matthias ; Pendall, Elise ; Phillips, Richard P. ; Pilegaard, Kim ; Pirk, Norbert ; Posse, Gabriela ; Powell, Thomas ; Prasse, Heiko ; Prober, Suzanne M. ; Rambal, Serge ; Rannik, Üllar ; Raz-Yaseef, Naama ; Reed, David ; Dios, Victor Resco de; Restrepo-Coupe, Natalia ; Reverter, Borja R. ; Roland, Marilyn ; Sabbatini, Simone ; Sachs, Torsten ; Saleska, Scott R. ; Sánchez-Cañete, Enrique P. ; Sanchez-Mejia, Zulia M. ; Schmid, Hans Peter ; Schmidt, Marius ; Schneider, Karl ; Schrader, Frederik ; Schroder, Ivan ; Scott, Russell L. ; Sedlák, Pavel ; Serrano-Ortíz, Penélope ; Shao, Changliang ; Shi, Peili ; Shironya, Ivan ; Siebicke, Lukas ; Šigut, Ladislav ; Silberstein, Richard ; Sirca, Costantino ; Spano, Donatella ; Steinbrecher, Rainer ; Stevens, Robert M. ; Sturtevant, Cove ; Suyker, Andy ; Tagesson, Torbern ; Takanashi, Satoru ; Tang, Yanhong ; Tapper, Nigel ; Thom, Jonathan ; Tiedemann, Frank ; Tomassucci, Michele ; Tuovinen, Juha Pekka ; Urbanski, Shawn ; Valentini, Riccardo ; Molen, Michiel van der; Gorsel, Eva van; Huissteden, Ko van; Varlagin, Andrej ; Verfaillie, Joseph ; Vesala, Timo ; Vincke, Caroline ; Vitale, Domenico ; Vygodskaya, Natalia ; Walker, Jeffrey P. ; Walter-Shea, Elizabeth ; Wang, Huimin ; Weber, Robin ; Westermann, Sebastian ; Wille, Christian ; Wofsy, Steven ; Wohlfahrt, Georg ; Wolf, Sebastian ; Woodgate, William ; Li, Yuelin ; Zampedri, Roberto ; Zhang, Junhui ; Zhou, Guoyi ; Zona, Donatella ; Agarwal, Deb ; Biraud, Sebastien ; Torn, Margaret ; Papale, Dario - \ 2020
    Scientific Data 7 (2020)1. - ISSN 2052-4463 - 1 p.

    The FLUXNET2015 dataset provides ecosystem-scale data on CO2, water, and energy exchange between the biosphere and the atmosphere, and other meteorological and biological measurements, from 212 sites around the globe (over 1500 site-years, up to and including year 2014). These sites, independently managed and operated, voluntarily contributed their data to create global datasets. Data were quality controlled and processed using uniform methods, to improve consistency and intercomparability across sites. The dataset is already being used in a number of applications, including ecophysiology studies, remote sensing studies, and development of ecosystem and Earth system models. FLUXNET2015 includes derived-data products, such as gap-filled time series, ecosystem respiration and photosynthetic uptake estimates, estimation of uncertainties, and metadata about the measurements, presented for the first time in this paper. In addition, 206 of these sites are for the first time distributed under a Creative Commons (CC-BY 4.0) license. This paper details this enhanced dataset and the processing methods, now made available as open-source codes, making the dataset more accessible, transparent, and reproducible.

    Fysisch-chemische inductie van plantweerbaarheid
    Stevens, L.H. ; Breeuwsma, S.J. ; Griekspoor, Y. ; Rutgers, B. - \ 2020
    Wageningen : Stichting Wageningen Research, Wageningen Plant Research Biointeracties en Plantgezondheid - 67
    In dit rapport wordt verslag gedaan van onderzoek naar de interactie tussen rood/verrood-LED-stuurlicht en inductie van plantweerbaarheid middels elicitors. Het onderzoek bestond uit een reeks min of meer uniforme kasexperimenten uitgevoerd met groepen van jonge tomatenplanten als modelgewas, aangevuld met gerbera en enkele perkplanten als sierteeltgewassen. Het beoogde weerbaarheidseffect betrof het zogenoemde systemic acquired resistance (SAR). De effecten van de behandelingen werden vastgesteld door bepaling van salicylzuur, van expressie van pathogenesis related (PR) proteins, en van de meeldauwontwikkeling.
    Repositioning of the global epicentre of non-optimal cholesterol
    Taddei, Cristina ; Zhou, Bin ; Bixby, Honor ; Carrillo-Larco, Rodrigo M. ; Danaei, Goodarz ; Jackson, Rod T. ; Farzadfar, Farshad ; Sophiea, Marisa K. ; Cesare, Mariachiara Di; Iurilli, Maria Laura Caminia ; Martinez, Andrea Rodriguez ; Asghari, Golaleh ; Dhana, Klodian ; Gulayin, Pablo ; Kakarmath, Sujay ; Santero, Marilina ; Voortman, Trudy ; Riley, Leanne M. ; Cowan, Melanie J. ; Savin, Stefan ; Bennett, James E. ; Stevens, Gretchen A. ; Paciorek, Christopher J. ; Aekplakorn, Wichai ; Cifkova, Renata ; Giampaoli, Simona ; Kengne, Andre Pascal ; Khang, Young Ho ; Kuulasmaa, Kari ; Laxmaiah, Avula ; Margozzini, Paula ; Mathur, Prashant ; Nordestgaard, Børge G. ; Zhao, Dong ; Aadahl, Mette ; Abarca-Gómez, Leandra ; Rahim, Hanan Abdul ; Abu-Rmeileh, Niveen M. ; Acosta-Cazares, Benjamin ; Adams, Robert J. ; Ferrieres, Jean ; Geleijnse, Johanna M. ; He, Yuna ; Jacobs, Jeremy M. ; Kromhout, Daan ; Ma, Guansheng ; Dam, Rob M. van; Wang, Qian ; Wang, Ya Xing ; Wang, Ying Wei - \ 2020
    Nature 582 (2020)7810. - ISSN 0028-0836 - p. 73 - 77.

    High blood cholesterol is typically considered a feature of wealthy western countries1,2. However, dietary and behavioural determinants of blood cholesterol are changing rapidly throughout the world3 and countries are using lipid-lowering medications at varying rates. These changes can have distinct effects on the levels of high-density lipoprotein (HDL) cholesterol and non-HDL cholesterol, which have different effects on human health4,5. However, the trends of HDL and non-HDL cholesterol levels over time have not been previously reported in a global analysis. Here we pooled 1,127 population-based studies that measured blood lipids in 102.6 million individuals aged 18 years and older to estimate trends from 1980 to 2018 in mean total, non-HDL and HDL cholesterol levels for 200 countries. Globally, there was little change in total or non-HDL cholesterol from 1980 to 2018. This was a net effect of increases in low- and middle-income countries, especially in east and southeast Asia, and decreases in high-income western countries, especially those in northwestern Europe, and in central and eastern Europe. As a result, countries with the highest level of non-HDL cholesterol—which is a marker of cardiovascular risk—changed from those in western Europe such as Belgium, Finland, Greenland, Iceland, Norway, Sweden, Switzerland and Malta in 1980 to those in Asia and the Pacific, such as Tokelau, Malaysia, The Philippines and Thailand. In 2017, high non-HDL cholesterol was responsible for an estimated 3.9 million (95% credible interval 3.7 million–4.2 million) worldwide deaths, half of which occurred in east, southeast and south Asia. The global repositioning of lipid-related risk, with non-optimal cholesterol shifting from a distinct feature of high-income countries in northwestern Europe, north America and Australasia to one that affects countries in east and southeast Asia and Oceania should motivate the use of population-based policies and personal interventions to improve nutrition and enhance access to treatment throughout the world.

    Green Challenges: plant en bodemweerbaarheidtegen ondergrondse ziekten
    Streminska, Marta ; Breeuwsma, Suzanne ; Huisman, Huei Ming ; Vos, Ric de; Eekelen, Henriette van; Stevens, Luc ; Salm, Caroline van der - \ 2020
    Bleiswijk : Stichting Wageningen Research, Wageningen Plant Research, Business unit Glastuinbouw (Rapport WPR 943) - 61
    Crops in soil-based and soilless greenhouse cultivation systems are susceptible to various soilborne diseases, such as foot and root rot and wilting, caused by pathogens as Fusarium and Pythium. The Grºeen Challenges project aims to reduce the use of chemical plant protection products and to develop new measures and strategies for disease and pest control through a system approach. This project investigated which measures can be taken to promote soil disease suppression and induced plant resistance against soilborne pathogens (Fusarium and Pythium) in different horticultural crops: vegetable crops (tomato and cucumber) and ornamental crop (lisianthus).
    Pioneering in the virtual classroom
    Dijksma, Roel ; Honing, Hannie van der; Stevens, Tim - \ 2020
    Social media dynamics in agro-food governance : Hypes, emotions and master terms
    Stevens, Tim M. - \ 2020
    Wageningen University. Promotor(en): M.N.C. Aarts; A.R.P.J. Dewulf, co-promotor(en): C.J.A.M. Termeer. - Wageningen : Wageningen University - ISBN 9789463953146 - 231

    This thesis examines the role of social media in the public debate about animal farming and food production in The Netherlands. The results of this case study provide insights into social media dynamics in the governance of wicked problems. More specifically, this thesis provides insights into: (1) the issues, events and actors that generate peak attention on social media; (2) the emergent dynamics that result from frame interactions; (3) the influence of social media dynamics on public debates and policies. The results demonstrate how social media create a public playing field that connects arenas and players, and changes the governance game.

    How farmers got to grips with social media
    Stevens, Tim - \ 2020
    Using Emotions to Frame Issues and Identities in Conflict: Farmer Movements on Social Media
    Stevens, Tim M. ; Aarts, Noelle ; Dewulf, Art - \ 2020
    Negotiation and Conflict Management Research (2020). - ISSN 1750-4708
    animal husbandry - animal welfare - conflict - emotion - framing - identity - social media

    Polarization and group formation processes on social media networks have received ample academic attention, but few studies have looked into the discursive interactions on social media through which intergroup conflicts develop. In this comparative case study, we analyzed two social media conflicts between farmers and animal right advocates to understand how conflicts establish, escalate, and return dormant through issue and identity framing and the discursive use of emotions. The results show that the two groups used the same set of frames throughout the three phases. We identify this as a symmetric conflict framing repertoire. The groups both use a dominant moral frame (animal welfare is of absolute value), but express distinct views on policy solutions. This triggers a contestation of credibility (who knows best and who cares most for animals) in which the two groups use the same set of issue and identity frames to directly oppose each other. The binary opposition is initially established through issue framing but escalates into an identity conflict that involves group labeling and blaming. The discursive use of emotion reinforces this escalation in two ways. First, it reinforces a vicious cycle in the contestation of credibility: While emotions are implicitly used to frame oneself as caring and trustworthy, emotion is explicitly used to frame the other party as deceptive and irrational. Second, disputants use collective emotions as a response to the other group’s offensive actions (blaming) and as a justification of one’s own collective actions. We discuss how this conflict differs from previously studied conflicts to provide plausible explanations for these findings.

    The emergence and evolution of master terms in the public debate about livestock farming: Semantic fields, communication strategies and policy practices
    Stevens, T.M. ; Aarts, M.N.C. ; Dewulf, A.R.P.J. - \ 2019
    Discourse, Context & Media 31 (2019). - ISSN 2211-6958
    master term - master frame - social media - hashtag - framing - agricultural policy
    In the new public space shaped by short, fast, and networked interactions on social media, single keywords, often used in combination with a hashtag, have become important framing devices that structure conversations and communities. This study provides insight into how keywords become dominant framing devices. We conduct a longitudinal comparative case study on the emergence and evolution of two dominant keywords in the Dutch livestock debate: plofkip (booster-broiler) and megastal (mega-stable). Based on an analysis of social media messages, news articles, and policy debates and documents, we study the role of keywords in semantic fields, communication strategies, and policy practices. We present four dynamics that help to understand how keywords become ‘master terms’: (1) loaded keywords for contested politicized objects can become powerful framing devices because they carry normative meaning and yet are open enough to be applied widely; (2) if activists explicitly and consistently relate the meaning of a loaded term to realities and responsibilities in the sector, the term becomes the signifier of an activist frame; (3) counter terms and frames increase attention, broaden the involvement of actors and deepen the conversation to a value-based debate, through which keywords become master terms; (4) master terms shape policy practices, which in turn reinforces the affordance of the terms in the conversation. We propose the concept of ‘master term’ as a keyword that not only reflects, but activates and establishes a master frame around which conversations and practices revolve.
    Browse preference in bonobos
    Depauw, Sarah ; Janssens, Geert P.J. ; Stevens, Jeroen M.G. ; Bosch, G. - \ 2019
    Rising rural body-mass index is the main driver of the global obesity epidemic in adults
    Bixby, Honor ; Bentham, James ; Zhou, Bin ; Cesare, Mariachiara Di; Paciorek, Christopher J. ; Bennett, James E. ; Taddei, Cristina ; Stevens, Gretchen A. ; Rodriguez-Martinez, Andrea ; Carrillo-Larco, Rodrigo M. ; Khang, Young Ho ; Sorić, Maroje ; Gregg, Edward W. ; Miranda, J.J. ; Bhutta, Zulfiqar A. ; Savin, Stefan ; Sophiea, Marisa K. ; Iurilli, Maria L.C. ; Solomon, Bethlehem D. ; Cowan, Melanie J. ; Riley, Leanne M. ; Danaei, Goodarz ; Bovet, Pascal ; Chirita-Emandi, Adela ; Hambleton, Ian R. ; Hayes, Alison J. ; Ikeda, Nayu ; Kengne, Andre P. ; Laxmaiah, Avula ; Li, Yanping ; McGarvey, Stephen T. ; Mostafa, Aya ; Neovius, Martin ; Starc, Gregor ; Zainuddin, Ahmad A. ; Abarca-Gómez, Leandra ; Abdeen, Ziad A. ; Abdrakhmanova, Shynar ; Abdul Ghaffar, Suhaila ; Abdul Hamid, Zargar ; Abubakar Garba, Jamila ; Ferrieres, Jean ; He, Yuna ; Jacobs, Jeremy M. ; Kromhout, Daan ; Ma, Guansheng ; Visser, Marjolein ; Wang, Qian ; Wang, Ya Xing ; Wang, Ying Wei - \ 2019
    Nature 569 (2019)7755. - ISSN 0028-0836 - p. 260 - 264.

    Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities 1,2 . This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity 3–6 . Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55% of the global rise in mean BMI from 1985 to 2017—and more than 80% in some low- and middle-income regions—was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing—and in some countries reversal—of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories.

    Het Online debat over de Oostvaardersplassen : De invloed van sociale media op natuurbeheer
    Mattijssen, T.J.M. ; Breman, B.C. ; Stevens, T.M. - \ 2019
    Landschap : tijdschrift voor landschapsecologie en milieukunde 36 (2019)1. - ISSN 0169-6300 - p. 4 - 13.
    Begin is gemaakt met gesekst sperma bij varkens
    Woelders, H. - \ 2019
    Temporal stability of Orbicella annularis symbioses: a case study in The Bahamas
    Kennedy, E.V. ; Tonk, Linda ; Foster, N.L. ; Mumby, P.J. ; Stevens, J.R. - \ 2019
    Bulletin of Marine Science 95 (2019)2. - ISSN 0007-4977 - p. 289 - 304.
    Orbicella annularis (Ellis and Solander, 1786), a key reef building species, is unusual among Caribbean corals in the flexibility it displays in its symbioses with dinoflagellates in the family Symbiodiniaceae. This variability has been documented at a range of spatial scales; from within and between colonies to scales spanning the entire species range. However, temporal variability in Symbiodiniaceae communities found within O. annularis colonies is not well understood. Evidence suggests that symbiont communities in this coral species fluctuate temporally in response to environmental stressors (sporadic changes in abundance and in community composition). In this study, we investigated temporal stability of symbiont communities in O. annularis at four sites in The Bahamas over a period spanning 6 yrs. While the dominant symbiont species, Breviolum minutum (LaJeunesse et al.) J.E.Parkinson & LaJeunesse (formerly ITS2-type B1), remained stable across four patch-reef study sites, finer resolution molecular techniques revealed inter-annual variability in the presence/ absence of cryptic species Durusdinium trenchii (LaJeunesse) LaJeunesse (formerly ITS2-type D1a). Durusdinium trenchii is known to play a role in resistance to environmental stress and may have a protective effect under warm conditions. These results suggest that, while it might take an extreme environmental perturbation to trigger a long-term shift in the dominant symbiont, at background levels, less prevalent symbiont taxa are likely to be continually shuffling their relative abundances as they change in response to seasonal or environmental changes.
    Species-specific alterations in Anopheles mosquito olfactory responses caused by Plasmodium infection
    Stanczyk, N.M. ; Brugman, V.A. ; Austin, V. ; Sanchez-Roman Teran, F. ; Gezan, S.A. ; Emery, M. ; Visser, T.M. ; Dessens, J.T. ; Stevens, W. ; Smallegange, R.C. ; Takken, W. ; Hurd, H. ; Caulfield, John ; Birkett, M. ; Pickett, J. ; Logan, J.G. - \ 2019
    Scientific Reports 9 (2019)1. - ISSN 2045-2322

    Mosquitoes infected with malaria parasites have demonstrated altered behaviour that may increase the probability of parasite transmission. Here, we examine the responses of the olfactory system in Plasmodium falciparum infected Anopheles gambiae, Plasmodium berghei infected Anopheles stephensi, and P. berghei infected An. gambiae. Infected and uninfected mosquitoes showed differential responses to compounds in human odour using electroantennography coupled with gas chromatography (GC-EAG), with 16 peaks triggering responses only in malaria-infected mosquitoes (at oocyst, sporozoite or both stages). A selection of key compounds were examined with EAG, and responses showed differences in the detection thresholds of infected and uninfected mosquitoes to compounds including lactic acid, tetradecanoic acid and benzothiazole, suggesting that the changes in sensitivity may be the reason for differential attraction and biting at the oocyst and sporozoite stages. Importantly, the different cross-species comparisons showed varying sensitivities to compounds, with P. falciparum infected An. gambiae differing from P. berghei infected An. stephensi, and P. berghei infected An. gambiae more similar to the P. berghei infected An. stephensi. These differences in sensitivity may reflect long-standing evolutionary relationships between specific Plasmodium and Anopheles species combinations. This highlights the importance of examining different species interactions in depth to fully understand the impact of malaria infection on mosquito olfactory behaviour.

    Gezocht: nieuwe grondstoffen voor varkensvoer
    Zanten, H.H.E. van - \ 2019

    Met het toewerken naar een circulaire landbouw moet de varkenshouderij minder afhankelijk worden van import van grondstoffen uit verre oorden. Alleen met reststromen gaat de sector het echter niet redden.

    Natuur 2.0 : Het natuurdebat op social media
    Breman, B.C. ; Mattijssen, T.J.M. ; Stevens, T.M. - \ 2018
    Wageningen : Wettelijke Onderzoekstaken Natuur & Milieu (WOt-technical report 131) - 92
    Social media are playing an increasingly important role in public debate. The aim of this analysis is to get a clear picture of how the subject of nature is represented on social media and how this affects the public debate on nature in the Netherlands. A range of software was used to collect social media posts about nature. These posts were then analysed using a combination of quantitative and qualitative methods at different levels (macro, meso, micro). The results show that nature is a live issue online and that it generally has positive connotations. At the same time, the confluence of different ideas about what nature really is can sometimes lead to heated discussions and a polarised debate. For a long time now the influence of this digital debate has extended beyond the online domain into the world of practical conservation management and nature policy.
    Using 'omic approaches to compare temporal bacterial colonization of lolium perenne, lotus corniculatus, and trifolium pratensein the Rumen
    Elliott, Christopher L. ; Edwards, Joan E. ; Wilkinson, Toby J. ; Allison, Gordon G. ; McCaffrey, Kayleigh ; Scott, Mark B. ; Rees-Stevens, Pauline ; Kingston-Smith, Alison H. ; Huws, Sharon A. - \ 2018
    Frontiers in Microbiology 9 (2018)SEP. - ISSN 1664-302X - 16 p.
    16S rRNA gene - Birds foot trefoil - CowPI - FTIR - Microbiome - Perennial ryegrass - Red clover - Rumen

    Understanding rumen plant-microbe interactions is central for development of novel methodologies allowing improvements in ruminant nutrient use efficiency. This study investigated rumen bacterial colonization of fresh plant material and changes in plant chemistry over a period of 24 h period using three different fresh forages: Lolium perenne (perennial ryegrass; PRG), Lotus corniculatus (bird's foot trefoil; BFT) and Trifolium pratense (red clover; RC). We show using 16S rRNA gene ion torrent sequencing that plant epiphytic populations present pre-incubation (0 h) were substantially different to those attached post incubations in the presence of rumen fluid on all forages. Thereafter primary and secondary colonization events were evident as defined by changes in relative abundances of attached bacteria and changes in plant chemistry, as assessed using Fourier transform infrared (FTIR) spectroscopy. For PRG colonization, primary colonization occurred for up to 4 h and secondary colonization from 4 h onward. The changes from primary to secondary colonization occurred significantly later with BFT and RC, with primary colonization being up to 6 h and secondary colonization post 6 h of incubation. Across all 3 forages the main colonizing bacteria present at all time points post-incubation were Prevotella, Pseudobutyrivibrio, Ruminococcus, Olsenella, Butyrivibrio, and Anaeroplasma (14.2, 5.4, 1.9, 2.7, 1.8, and 2.0% on average respectively), with Pseudobutyrivibrio and Anaeroplasma having a higher relative abundance during secondary colonization. Using CowPI, we predict differences between bacterial metabolic function during primary and secondary colonization. Specifically, our results infer an increase in carbohydrate metabolism in the bacteria attached during secondary colonization, irrespective of forage type. The CowPI data coupled with the FTIR plant chemistry data suggest that attached bacterial function is similar irrespective of forage type, with the main changes occurring between primary and secondary colonization. These data suggest that the sward composition of pasture may have major implications for the temporal availability of nutrients for animal.

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