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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Relaxation Behavior and Nonlinear Surface Rheology of PEO-PPO-PEO Triblock Copolymers at the Air-Water Interface
Moghimikheirabadi, Ahmad ; Fischer, Peter ; Kröger, Martin ; Sagis, Leonard M.C. - \ 2019
Langmuir 35 (2019)44. - ISSN 0743-7463 - p. 14388 - 14396.

Surface dilatational viscoelasticity of adsorbed layers of pluronics triblock copolymers at the air-water interface was measured using the oscillating barrier technique. The effect of molecular architecture and concentration on surface viscoelasticity was explored for two different types of pluronics with different degrees of hydrophobicity, Pluronic F-108 (Mw ≈ 14600 g/mol) and Pluronic P-123 (Mw ≈ 5800 g/mol), the former exhibiting a larger hydrophilic to hydrophobic block length ratio. Frequency sweeps in the linear regime suggested that interfacial films of F-108 have higher surface limiting elasticity and larger in-plane and out-of-plane relaxation times at the same bulk concentration (the former possibly related to in-plane microstructure rearrangements, the latter to surface/bulk diffusion). Increasing the bulk concentration of pluronics from 1 to 100 μM led to a decrease in both in- and out-of-plane relaxation times. Large amplitude oscillatory dilatation (LAOD) tests were performed to capture nonlinear behavior of these interfacial films by means of elastic and viscous Lissajous plots. Nonlinearities in elastic responses were quantified through calculation of the strain-stiffening indices in extension SE and compression SC. Both pluronics exhibited strain softening in extension. In compression, P-123 showed strain-hardening and F-108 displayed a relatively linear response. Apparent strain hardening in extension was observed for the P-123 adsorbed film, at high strain, at a bulk concentration of 100 μM. However, at these strains, the response was dominated by the viscous contribution and calculation of strain rate-thickening factors in extension and compression showed that the overall response was strain rate-thinning in extension and strain rate-thickening in compression.

Comparison of different invasive and non-invasive methods to characterize intestinal microbiota throughout a production cycle of broiler chickens
Kers, Jannigje G. ; Fischer, Egil A.J. ; Stegeman, J.A. ; Smidt, Hauke ; Velkers, Francisca C. - \ 2019
Microorganisms 7 (2019)10. - ISSN 2076-2607
16S rRNA - Avian - Gut - Methods - Microbiome - Poultry

In the short life of broiler chickens, their intestinal microbiota undergoes many changes. To study underlying biological mechanisms and factors that influence the intestinal microbiota development, longitudinal data from flocks and individual birds is needed. However, post-mortem collection of samples hampers longitudinal data collection. In this study, invasively collected cecal and ileal content, cloacal swabs collected from the same bird, and boot sock samples and cecal droppings from the litter of the broilers’ poultry house, were collected on days 0, 2, 7, 14 and 35 post-hatch. The different sample types were evaluated on their applicability and reliability to characterize the broiler intestinal microbiota. The microbiota of 247 samples was assessed by 16S ribosomal RNA gene amplicon sequencing. Analyses of α and β measures showed a similar development of microbiota composition of cecal droppings compared to cecal content. Furthermore, the composition of cecal content samples was comparable to that of the boot socks until day 14 post-hatch. This study shows that the value of non-invasive sample types varies at different ages and depends on the goal of the microbiota characterization. Specifically, cecal droppings and boot socks may be useful alternatives for cecal samples to determine intestinal microbiota composition longitudinally.

A nexus modeling framework for assessing water scarcity solutions
Kahil, Taher ; Albiac, Jose ; Fischer, Guenther ; Strokal, Maryna ; Tramberend, Sylvia ; Greve, Peter ; Tang, Ting ; Burek, Peter ; Burtscher, Robert ; Wada, Yoshihide - \ 2019
Current Opinion in Environmental Sustainability 40 (2019). - ISSN 1877-3435 - p. 72 - 80.

Water scarcity has become a crucial environmental issue worldwide. It has increased substantially in the last decades in many parts of the world, and it is expected to further exacerbate in the future driven by socio-economic and climatic changes. Several solution options could be implemented to address this growing water scarcity, including supply and demand-side management options that span the water, energy, and agricultural sectors. However, these options involve tradeoffs among various societal objectives, especially when the interactions between these objectives are not properly considered. This paper provides a review of the impending water scarcity challenges and suggests assessing water scarcity solution options using a nexus modeling framework that links well-established sectoral-oriented models.

Effect of challenge dose of plasmid-mediated extended-spectrum β-lactamase and AmpC β-lactamase producing Escherichia coli on time-until-colonization and level of excretion in young broilers
Dame-Korevaar, Anita ; Fischer, Egil A.J. ; Goot, Jeanet van der; Velkers, Francisca ; Broek, Jan van den; Veldman, Kees ; Ceccarelli, Daniela ; Mevius, Dik ; Stegeman, Arjan - \ 2019
Veterinary Microbiology 239 (2019). - ISSN 0378-1135
Animal model - Antibiotic resistance - Dose-response - Inoculation - Poultry - Transmission

Plasmid-mediated extended-spectrum β-lactamase and AmpC β-lactamase (ESBL/pAmpC) producing bacteria are present at all levels of the broiler production pyramid. Young birds can be found positive for ESBL/pAmpC-producing Escherichia coli shortly after arrival at farm. The aim of this study was to determine the effect of different challenge doses of ESBL/pAmpC-producing E. coli on time-until-colonization and the level of excretion in young broilers. One-day-old broilers (specific-pathogen free (SPF) and conventional Ross 308) were housed in isolators and challenged with 0.5 ml ESBL/pAmpC-producing E. coli strains of varying doses (101–105 CFU/ml). Presence and concentration (CFU/gram feces) of ESBL/pAmpC-producing E. coli and total E. coli were determined longitudinally from cloacal swabs, and in cecal content 72 h after challenge. Higher challenge doses resulted in shorter time-until-colonization. However, even the lowest dose (101 CFU/ml) resulted in colonization of the broilers which excreted >106 CFU/gram feces 72 h after inoculation. Conventional broilers were colonized later than SPF broilers, although within 72 h after challenge all broilers were excreting ESBL/pAmpC-producing E. coli. A probabilistic model was used to estimate the probability of colonization by initial inoculation or transmission. The higher the dose the higher the probability of excreting ESBL/pAmpC-producing E. coli as a result of inoculation. In conclusion, low initial doses of ESBL/pAmpC-producing E. coli can result in rapid colonization of a flock. Interventions should thus be aimed to eliminate ESBL/pAmpC-producing bacteria in the environment of the hatchlings and measures focusing at reducing colonization and transmission of ESBL/pAmpC-producing E. coli should be applied shortly after hatching.

Competition between Escherichia coli Populations with and without Plasmids Carrying a Gene Encoding Extended-Spectrum Beta-Lactamase in the Broiler Chicken Gut
Fischer, Egil A.J. ; Dierikx, Cindy M. ; Essen-Zandbergen, Alieda van; Mevius, Dik ; Stegeman, Arjan ; Velkers, Francisca C. ; Klinkenberg, Don - \ 2019
Applied and Environmental Microbiology 85 (2019)17. - ISSN 0099-2240
antibiotic resistance - Bayesian model - challenge - conjugation - experiment - poultry

Extended-spectrum-beta-lactamase (ESBL)/AmpC-producing Escherichia coli strains are widely found in E. coli isolates from broiler feces, largely due to the presence of the blaCTX-M-1 gene on IncI1 plasmids. Plasmid carriage is theorized to cause fitness loss and thus should decrease under conditions of reduced antibiotic use. However, in vitro studies showed plasmid carriage to increase in the absence of antimicrobials, due to plasmid conjugation. We investigated whether this translates to increased levels of plasmid in the gastrointestinal tracts of chickens, where conjugation rates may be different and subtle differences in growth rates may have a larger impact on colonization. Eight groups of five chickens were orally inoculated at 4 days of age with a 0.5-ml volume containing 106 CFU/ml E. coli cells, of which 0%, 0.1%, 10%, or 100% carried the IncI1 plasmid with the gene blaCTX-M-1 At 13 time points during 41 days, fecal samples were taken from each chicken. E. coli strains with and without plasmids were quantified. Trends in E. coli subpopulations were analyzed using generalized linear mixed models, and population dynamics were studied by fitting to a mechanistic model. Trends in E. coli subpopulations were different between groups rather than between individual chickens, suggesting substantial levels of E. coli exchange between chickens in a group. The IncI1 plasmid carrying blaCTX-M-1 was transferred with conjugation coefficients at levels higher than those observed in vitro Across groups, the plasmids disappeared or were established independently of the initial fraction of plasmid-carrying E. coli, but no major increase occurred as observed in vitro Differences in growth rates were observed, but competitive exclusion of plasmid-carrying variants was counteracted by conjugation.IMPORTANCE Bacteria that produce extended-spectrum beta-lactamases are resistant to an important class of antimicrobials in human and veterinary medicine. Reduction in antibiotic use is expected to decrease the prevalence of resistance. However, resistance genes often lie on plasmids which can be copied and transferred to other bacteria by conjugation, so in vitro resistance was observed to increase in the absence of antimicrobials. We sought to determine whether this also occurs in the chicken gut and if competitive exclusion by similar E. coli variants without the resistance occurred. We studied the excretion of E. coli carrying IncI1 plasmids with the blaCTX-M-1 resistance gene in small groups of broiler chickens, after inoculating the chickens with E. coli suspensions containing different fractions of plasmid-carrying cells. Our results showed little variation between chickens within groups but large differences between groups that were independent of the ratio of variants with and without the plasmid and with persistence or extinction of the plasmid. However, there was no major plasmid increase as observed in vitro We conclude that in vivo studies with sufficient independent replications are important for intervention studies on plasmid-mediated antimicrobial resistance.

Transferring biodiversity-ecosystem function research to the management of ‘real-world’ ecosystems
Manning, P. ; Loos, Jacqueline ; Barnes, Andrew D. ; Batáry, Péter ; Bianchi, Felix J.J.A. ; Buchmann, Nina ; Deyn, Gerlinde B. De; Ebeling, Anne ; Eisenhauer, Nico ; Fischer, Markus ; Fründ, Jochen ; Grass, Ingo ; Isselstein, Johannes ; Jochum, M. ; Klein, Alexandra M. ; Klingenberg, Esther O.F. ; Landis, Douglas A. ; Lepš, Jan ; Lindborg, Regina ; Meyer, Sebastian T. ; Temperton, Vicky M. ; Westphal, Catrin ; Tscharntke, Teja - \ 2019
In: Advances in Ecological Research Academic Press Inc. (Advances in Ecological Research )
BEF research - Biodiversity experiments - Ecosystem management - Ecosystem services - Grasslands - Knowledge transfer

Biodiversity-ecosystem functioning (BEF) research grew rapidly following concerns that biodiversity loss would negatively affect ecosystem functions and the ecosystem services they underpin. However, despite evidence that biodiversity strongly affects ecosystem functioning, the influence of BEF research upon policy and the management of ‘real-world’ ecosystems, i.e., semi-natural habitats and agroecosystems, has been limited. Here, we address this issue by classifying BEF research into three clusters based on the degree of human control over species composition and the spatial scale, in terms of grain, of the study, and discussing how the research of each cluster is best suited to inform particular fields of ecosystem management. Research in the first cluster, small-grain highly controlled studies, is best able to provide general insights into mechanisms and to inform the management of species-poor and highly managed systems such as croplands, plantations, and the restoration of heavily degraded ecosystems. Research from the second cluster, small-grain observational studies, and species removal and addition studies, may allow for direct predictions of the impacts of species loss in specific semi-natural ecosystems. Research in the third cluster, large-grain uncontrolled studies, may best inform landscape-scale management and national-scale policy. We discuss barriers to transfer within each cluster and suggest how new research and knowledge exchange mechanisms may overcome these challenges. To meet the potential for BEF research to address global challenges, we recommend transdisciplinary research that goes beyond these current clusters and considers the social-ecological context of the ecosystems in which BEF knowledge is generated. This requires recognizing the social and economic value of biodiversity for ecosystem services at scales, and in units, that matter to land managers and policy makers.

Data from: The interplay of landscape composition and configuration: new pathways to manage functional biodiversity and agro-ecosystem services across Europe
Martin, Emily A. ; Dainese, Matteo ; Clough, Yann ; Báldi, András ; Bommarco, R. ; Gagic, Vesna ; Garratt, Michael P.D. ; Holzschuh, Andrea ; Kleijn, D. ; Kovács-Hostyánszki, Anikó ; Marini, Lorenzo ; Potts, Simon G. ; Smith, Henrik G. ; Hassan, Diab Al; Albrecht, Matthias ; Andersson, Georg K.S. ; Asís, Josep D. ; Aviron, Stéphanie ; Balzan, M.V. ; Baños-Picón, Laura ; Bartomeus, Ignasi ; Batáry, Péter ; Burel, Francoise ; Caballero-lópez, Berta ; Concepción, Elena D. ; Coudrain, Valérie ; Dänhardt, Juliana ; Diaz, Mario ; Diekötter, Tim ; Dormann, Carsten F. ; Duflot, Rémi ; Entling, Martin H. ; Farwig, Nina ; Fischer, Christina ; Frank, Thomas ; Garibaldi, Lucas A. ; Hermann, John ; Herzog, Felix ; Inclán, Diego J. ; Jacot, Katja ; Jauker, Frank ; Jeanneret, Philippe ; Kaiser, Marina ; Krauss, Jochen ; Féon, Violette Le; Marshall, Jon ; Moonen, Anna Camilla ; Moreno, Gerardo ; Riedinger, Verena ; Rundlöf, Maj ; Rusch, Adrien ; Scheper, J.A. ; Schneider, Gudrun ; Schüepp, Christof ; Stutz, Sonja ; Sutter, Louis ; Tamburini, Giovanni ; Thies, Carsten ; Tormos, José ; Tscharntke, Teja ; Tschumi, Matthias ; Uzman, Deniz ; Wagner, Christian ; Zubair Anjum, Muhammad ; Steffan-Dewenter, Ingolf - \ 2019
biodiversity - agroecosystem - landscape composition - landscape configuration - functional traits - arthropods - natural pest control - pollination - yields
Managing agricultural landscapes to support biodiversity and ecosystem services is a key aim of a sustainable agriculture. However, how the spatial arrangement of crop fields and other habitats in landscapes impacts arthropods and their functions is poorly known. Synthesising data from 49 studies (1515 landscapes) across Europe, we examined effects of landscape composition (% habitats) and configuration (edge density) on arthropods in fields and their margins, pest control, pollination and yields. Configuration effects interacted with the proportions of crop and non‐crop habitats, and species’ dietary, dispersal and overwintering traits led to contrasting responses to landscape variables. Overall, however, in landscapes with high edge density, 70% of pollinator and 44% of natural enemy species reached highest abundances and pollination and pest control improved 1.7‐ and 1.4‐fold respectively. Arable‐dominated landscapes with high edge densities achieved high yields. This suggests that enhancing edge density in European agroecosystems can promote functional biodiversity and yield‐enhancing ecosystem services.
Dynamics of faecal shedding of ESBL- or AmpC-producing Escherichia coli on dairy farms
Hordijk, Joost ; Fischer, Egil A.J. ; Werven, Tine van; Sietsma, Steven ; Gompel, Liese Van; Timmerman, Arjen J. ; Spaninks, Mirlin P. ; Heederik, Dick J.J. ; Nielen, Mirjam ; Wagenaar, Jaap A. ; Stegeman, Arjan - \ 2019
Journal of Antimicrobial Chemotherapy 74 (2019)6. - ISSN 0305-7453 - p. 1531 - 1538.

OBJECTIVES: To explore the dynamics of faecal ESBL/AmpC shedding in dairy cattle and farmers, a study was conducted to examine changes in shedding by individual animals, as well as environmental exposure, and to study the association between antimicrobial use (AMU) and ESBL/AmpC shedding. METHODS: The study comprised a cross-sectional survey of 20 farms and a 1 year follow-up of 10 farms. Faecal samples were cultured by both direct inoculation on MacConkey agar + 1 mg/L cefotaxime (MC+) and enrichment in LB-broth + 1 mg/L cefotaxime with subsequent inoculation on MC+. Dust samples were collected using electrostatic dustfall collectors (EDCs). Human faecal samples were collected by the farmers. Presence of ESBL/AmpC genes was screened for by PCR and sequencing. Using mixed effects logistic regression, ORs were determined and population-attributable fractions (PAFs) calculated subsequently. RESULTS: In Phase 1, 8/20 farms were positive for ESBL/AmpC and, with 2 negative farms, were selected for Phase 2. Transient shedding of dominant allele variants was observed in the animals. EDCs and human faecal samples did not reflect what was observed in the animals. AMU was related to shedding of ESBLs in the next sampling moment [OR 14.6 (95% CI 3.0-80.0)] and the PAF of AMU was 0.36 (95% CI 0.08-0.77). Calves fed with colostrum from cows on dry-off therapy was not a risk factor [OR 1.7 (95% CI 0.7-4.9, P = 0.28)]. CONCLUSIONS: The presence of ESBL/AmpC could only be partly explained by AMU. No link was shown between shedding in cattle and humans or the environment. Interventions should focus on prevention of introduction.

What is the best housing temperature to translate mouse experiments to humans?
Keijer, Jaap ; Li, Min ; Speakman, John R. - \ 2019
Molecular Metabolism 25 (2019). - ISSN 2212-8778 - p. 168 - 176.
Basal metabolic rate - Comparative physiology - Housing temperature - Human - Mouse - Thermoneutrality

Objectives: Ambient temperature impinges on energy metabolism in a body size dependent manner. This has implications for the housing temperature at which mice are best compared to humans. In 2013, we suggested that, for comparative studies, solitary mice are best housed at 23–25 °C, because this is 3–5 °C below the mouse thermoneutral zone and humans routinely live 3–5 °C below thermoneutrality, and because this generates a ratio of DEE to BMR of 1.6–1.9, mimicking the ratio found in free-living humans. Methods: Recently, Fischer et al. (2017) challenged this estimate. By studying mice at 21 °C and at 30 °C (but notably not at 23–25 °C) they concluded that 30 °C is the optimal housing temperature. Here, we measured energy metabolism of C57BL/6 mice over a range of temperatures, between 21.4 °C and 30.2 °C. Results: We observed a ratio of DEE to BMR of 1.7 at 27.6 °C and of 1.8 at 25.5 °C, suggesting that this is the best temperature range for housing C57BL/6 mice to mimic human thermal relations. We used a 24 min average to calculate the ratio, similar to that used in human studies, while the ratio calculated by Fisher et al. dependent on short, transient metabolic declines. Conclusion: We concur with Fisher et al. and others that 21 °C is too cool, but we continue to suggest that 30 °C is too warm. We support this with other data. Finally, to mimic living environments of all humans, and not just those in controlled Western environments, mouse experimentation at various temperatures is likely required.

The interplay of landscape composition and configuration: new pathways to manage functional biodiversity and agroecosystem services across Europe
Martin, Emily A. ; Dainese, Matteo ; Clough, Yann ; Báldi, András ; Bommarco, Riccardo ; Gagic, Vesna ; Garratt, Michael P.D. ; Holzschuh, Andrea ; Kleijn, David ; Kovács-Hostyánszki, Anikó ; Marini, Lorenzo ; Potts, Simon G. ; Smith, Henrik G. ; Hassan, Diab Al; Albrecht, Matthias ; Andersson, Georg K.S. ; Asís, Josep D. ; Aviron, Stéphanie ; Balzan, Mario V. ; Baños-Picón, Laura ; Bartomeus, Ignasi ; Batáry, Péter ; Burel, Francoise ; Caballero-López, Berta ; Concepción, Elena D. ; Coudrain, Valérie ; Dänhardt, Juliana ; Diaz, Mario ; Diekötter, Tim ; Dormann, Carsten F. ; Duflot, Rémi ; Entling, Martin H. ; Farwig, Nina ; Fischer, Christina ; Frank, Thomas ; Garibaldi, Lucas A. ; Hermann, John ; Herzog, Felix ; Inclán, Diego ; Jacot, Katja ; Jauker, Frank ; Jeanneret, Philippe ; Kaiser, Marina ; Krauss, Jochen ; Féon, Violette Le; Marshall, Jon ; Moonen, Anna Camilla ; Moreno, Gerardo ; Riedinger, Verena ; Rundlöf, Maj ; Rusch, Adrien ; Scheper, Jeroen ; Schneider, Gudrun ; Schüepp, Christof ; Stutz, Sonja ; Sutter, Louis ; Tamburini, Giovanni ; Thies, Carsten ; Tormos, José ; Tscharntke, Teja ; Tschumi, Matthias ; Uzman, Deniz ; Wagner, Christian ; Zubair-Anjum, Muhammad ; Steffan-Dewenter, Ingolf - \ 2019
Ecology Letters 22 (2019)7. - ISSN 1461-023X - p. 1083 - 1094.
Agroecology - arthropod community - biological control - edge density - pest control - pollination - response trait - semi-natural habitat - trait syndrome - yield

Managing agricultural landscapes to support biodiversity and ecosystem services is a key aim of a sustainable agriculture. However, how the spatial arrangement of crop fields and other habitats in landscapes impacts arthropods and their functions is poorly known. Synthesising data from 49 studies (1515 landscapes) across Europe, we examined effects of landscape composition (% habitats) and configuration (edge density) on arthropods in fields and their margins, pest control, pollination and yields. Configuration effects interacted with the proportions of crop and non-crop habitats, and species’ dietary, dispersal and overwintering traits led to contrasting responses to landscape variables. Overall, however, in landscapes with high edge density, 70% of pollinator and 44% of natural enemy species reached highest abundances and pollination and pest control improved 1.7- and 1.4-fold respectively. Arable-dominated landscapes with high edge densities achieved high yields. This suggests that enhancing edge density in European agroecosystems can promote functional biodiversity and yield-enhancing ecosystem services.

Extrinsic wheat fibre consumption enhances faecal bulk and stool frequency; A randomized controlled trial
Wit, Nicole De; Esser, Diederik ; Siebelink, Els ; Fischer, Anne ; Sieg, Juergen ; Mes, Jurriaan - \ 2019
Food & Function 10 (2019)2. - ISSN 2042-6496 - p. 646 - 651.

The beneficial effect of wheat fibres on faecal bulk and stool pattern has mainly been observed with intact wheat fibres. This study investigates the effect of extrinsic wheat fibre (VITACEL® wheat fibre), which can be easily incorporated in many food products, on faecal bulk, stool pattern, gastrointestinal complaints, satiety and food liking. In a double-blind randomized crossover trial, healthy male volunteers received meal boxes for 10 days, containing various food products enriched with extrinsic wheat fibre (∼20 grams of additional fibre per day) or control food products containing conventional levels of fibre with similar taste, appearance and caloric values. Meal boxes were integrated in the normal dietary pattern. Stool frequency, stool consistency, gastrointestinal complaints, satiety and product liking were assessed daily, and the last 5 days of each intervention, participants collected all their faeces to analyse faecal bulk. We found that consumption of extrinsic wheat fibre-enriched products significantly enhanced faecal bulk; faecal wet and dry weight showed a 1.41 ± 0.1 and 1.55 ± 0.1 times increase compared to control, respectively (p < 0.01). Extrinsic wheat fibre intervention furthermore increased stool frequency (1.3 ± 0.1 defecations per day compared to 1.1 ± 0.1 defecations per day during control diet, p < 0.05), but did not affect stool consistency, satiety, gastrointestinal complaints or product liking. So, increased consumption of extrinsic wheat fibre enhances faecal bulk and stool frequency. As this extrinsic wheat fibre can be easily incorporated in many food products without affecting appearance or taste, it might facilitate the increase of overall fibre intake and subsequently improve (intestinal) health.

Highly Porous Nanocrystalline UiO-66 Thin Films via Coordination Modulation Controlled Step-by-Step Liquid-Phase Growth
Semrau, A.L. ; Wannapaiboon, Suttipong ; Pujari, Sidharam P. ; Vervoorts, Pia ; Albada, Bauke ; Zuilhof, Han ; Fischer, Roland A. - \ 2019
Crystal Growth and Design 19 (2019)3. - ISSN 1528-7483 - p. 1738 - 1747.

Metal-organic frameworks (MOFs) possess exciting properties, which can be tailored by rational material design approaches. Integration of MOFs in functional nano- and mesoscale systems require selective crystallite positioning and thin-film growth techniques. Stepwise layer-by-layer liquid-phase epitaxy (LPE) emerged as one of the methods of choice to fabricate MOF@substrate systems. The layer-by-layer approach of LPE allows a precise control over the film thickness and crystallite orientation. However, these advantages were mostly observed in cases of tetra-connected dinuclear paddle-wheel MOFs and Hoffmann-type MOFs. Higher connected MOFs (consisting of nodes with 8-12 binding sites), such as the Zr-oxo cluster based families, are notoriously hard to deposit in an acceptable quality by the stepwise liquid-phase process. Herein, we report the use of coordination modulation (CM) to assist and enhance the LPE growth of UiO-66, Zr 6 O 4 (OH) 4 (bdc) 6 (bdc 2- = 1,4-benzene-dicarboxylate) films. Highly porous and crystalline thin films were obtained with good control of the crystallite domain size and film thickness in the nanoscale regime. The crystallinity (by grazing incidence X-ray diffraction), morphology (by scanning electron microscopy, atomic form microscopy), elemental composition (by X-ray photoelectron spectroscopy), binding properties (by infrared spectroscopy), and adsorption capacity (by quartz crystal microbalance adsorption experiments) for volatile organic compounds (e.g. CH 3 OH) of the fabricated thin films were investigated. These results substantiate a proof-of-concept of CM-LPE of MOFs and could be the gateway to facilitate in general the deposition of chemically very robust and higher-connected MOF thin films with automatic process-controlled LPE techniques under mild synthetic conditions.

Transmission routes of ESBL/pAmpC producing bacteria in the broiler production pyramid, a literature review
Dame-Korevaar, Anita ; Fischer, Egil A.J. ; Goot, Jeanet van der; Stegeman, Arjan ; Mevius, Dik - \ 2019
Preventive Veterinary Medicine 162 (2019). - ISSN 0167-5877 - p. 136 - 150.
Antimicrobial resistance - Evidence - Mechanisms - Poultry - Spread

Plasmid mediated Extended Spectrum Beta-Lactamase and AmpC Beta-Lactamase (ESBL/pAmpC) producing bacteria are resistant to beta-lactam antimicrobials and are widespread in humans, the environment and animals. Animals, especially broilers, are an important reservoir of ESBL/pAmpC producing bacteria. To control ESBL/pAmpC prevalence in broilers, transmission within the entire broiler production pyramid should be considered. This study, including 103 articles originating from two electronic databases, searched for evidence for possible routes of transmission of ESBL/pAmpC producing bacteria in the broiler production pyramid. Possible routes of transmission were categorised as 1) vertical between generations, 2) at hatcheries, 3) horizontal on farm, and 4) horizontal between farms and via the environment of farms. This review presents indications for transmission of ESBL/pAmpC producing bacteria for each of these routes. However, the lack of quantitative results in the literature did not allow an estimation of the relative contribution or magnitude of the different routes. Future research should be specifically targeted towards such information as it is crucial to guide reduction strategies for the spread of ESBL/pAmpC producing bacteria in the broiler production chain.

Modelling consumer choice through the random regret minimization model : An application in the food domain
Biondi, Beatrice ; Lans, Ivo A. Van der; Mazzocchi, Mario ; Fischer, Arnout R.H. ; Trijp, Hans C.M. Van; Camanzi, Luca - \ 2019
Food Quality and Preference 73 (2019). - ISSN 0950-3293 - p. 97 - 109.
Choice experiment - Consumer behaviour - Discrete-choice model - Food choice - Individual differences - Regret minimization

In line with findings on post-purchase food-choice regret, one can expect that pre-purchase anticipated regret with respect to forgone (non-chosen) alternatives has an impact on consumer food choices, especially when the choice is considered to be important. The traditional Random Utility Maximization (RUM) models for discrete choices may not fully capture this impact. This study investigates the usefulness and potential in the food domain of a discrete choice model that follows the regret minimization principle, the Random Regret Minimization (RRM) model, as an alternative and complement to existing RUM models. The two models are applied to consumer stated choices of cheese in a choice experiment. The study also investigates whether and to what extent a number of personality traits determine whether particular consumers rather choose according to utility-maximization, or regret-minimization principles. Results show that at the aggregate level the two models have a similar goodness of fit to the data and prediction ability. Still, each of them shows better fit for particular subgroups of consumers, based on personality traits. Hence, the present study reveals a potential for the RRM model applications in the food domain, and adds to the empirical literature supporting previous findings on the RRM model found in other contexts. Further research is needed to explore in which situations and for which consumer segments the RRM model is the most useful model.

Farming and food systems potentials
Dixon, J. ; Boffa, J.M. ; Williams, T.O. ; Leeuw, J. de; Fischer, G. ; Velthuizen, H. van - \ 2019
In: Farming Systems and Food Security in Africa / Dixon, J., Garrity, D., Boffa, J.M., Williams, T.O., Amede, T., Auricht, C., Lott, R., Mburathi, G., Routledge, Taylor & Francis Group (Earthscan food and agriculture ) - ISBN 9781138963351
Plant species richness and functional groups have different effects on soil water content in a decade-long grassland experiment
Fischer, Christine ; Leimer, Sophia ; Roscher, Christiane ; Ravenek, Janneke ; Kroon, Hans de; Kreutziger, Yvonne ; Baade, Jussi ; Beßler, Holger ; Eisenhauer, Nico ; Weigelt, Alexandra ; Mommer, Liesje ; Lange, Markus ; Gleixner, Gerd ; Wilcke, Wolfgang ; Schröder, Boris ; Hildebrandt, Anke - \ 2019
Journal of Ecology 107 (2019)1. - ISSN 0022-0477 - p. 127 - 141.
biodiversity - functional groups - Jena Experiment - plant–soil–water relation - soil water content - spatial–temporal variability - species richness

The temporal and spatial dynamics of soil water are closely interlinked with terrestrial ecosystems functioning. The interaction between plant community properties such as species composition and richness and soil water mirrors fundamental ecological processes determining above-ground–below-ground feedbacks. Plant–water relations and water stress have attracted considerable attention in biodiversity experiments. Yet, although soil scientific research suggests an influence of ecosystem productivity on soil hydraulic properties, temporal changes of the soil water content and soil hydraulic properties remain largely understudied in biodiversity experiments. Thus, insights on how plant diversity—productivity relationships affect soil water are lacking. Here, we determine which factors related to plant community composition (species and functional group richness, presence of plant functional groups) and soil (organic carbon concentration) affect soil water in a long-term grassland biodiversity experiment (The Jena Experiment). Both plant species richness and the presence of particular functional groups affected soil water content, while functional group richness played no role. The effect of species richness changed from positive to negative and expanded to deeper soil with time. Shortly after establishment, increased topsoil water content was related to higher leaf area index in species-rich plots, which enhanced shading. In later years, higher species richness increased topsoil organic carbon, likely improving soil aggregation. Improved aggregation, in turn, dried topsoils in species-rich plots due to faster drainage of rainwater. Functional groups affected soil water distribution, likely due to plant traits affecting root water uptake depths, shading, or water-use efficiency. For instance, topsoils in plots containing grasses were generally drier, while plots with legumes were moister. Synthesis. Our decade-long experiment reveals that the maturation of grasslands changes the effects of plant richness from influencing soil water content through shading effects to altering soil physical characteristics in addition to modification of water uptake depth. Functional groups affected the soil water distribution by characteristic shifts of root water uptake depth, but did not enhance exploitation of the overall soil water storage. Our results reconcile previous seemingly contradictory results on the relation between grassland species diversity and soil moisture and highlight the role of vegetation composition for soil processes.

Biocultural diversity: A novel concept to assess human-nature interrelations, nature conservation and stewardship in cities
Elands, B.H.M. ; Vierikko, K. ; Andersson, E. ; Fischer, L.K. ; Gonçalves, P. ; Haase, D. ; Kowarik, Ingo ; Luz, A.C. ; Niemelä,, J. ; Santos-Reis, M. ; Wiersum, K.F. - \ 2019
Urban Forestry and Urban Greening 40 (2019). - ISSN 1618-8667 - p. 29 - 34.
Biocultural diversity is an evolving perspective for studying the interrelatedness between people and their natural environment, not only in ecoregional hotspots and cultural landscapes, but also in urban green spaces. Developed in the 1990s in order to denote the diversity of life in all its manifestations―biological, cultural and linguistic―co-evolving within complex socio-ecological systems such as cities, biocultural diversity was identified in the GREEN SURGE project as a response to recent challenges cities face. Most important challenges are
the loss of nature and degradation of ecosystems in and around cities as well as an alienation of urban residents from and loss of interaction with nature. The notion of biocultural diversity is dynamic in nature and takes local values and practices of relating to biodiversity of different cultural groups as a starting point for sustainable living with biodiversity. The issue is not only how to preserve or restore biocultural practices and values, but also how to modify, adapt and create biocultural diversity in ways that resonate with urban transformations. As future societies will largely diverge from today’s societies, the cultural perspective on living with (urban) nature needs careful reconsideration. Biocultural diversity is not conceived as a definite concept providing prescriptions of what to see and study, but as a reflexive and sensitising concept that can be used to assess the different values and knowledge of people that reflect how they live with biodiversity. This short communication paper introduces a conceptual framework for studying the multi-dimensional features of biocultural diversity in cities along the three key dimensions of materialized, lived and stewardship, being departure points from which biocultural diversity can be studied.
Duckweed as human food. The influence of meal context and information on duckweed acceptability of Dutch consumers
Beukelaar, Myrthe F.A. de; Zeinstra, Gertrude G. ; Mes, Jurriaan J. ; Fischer, Arnout R.H. - \ 2019
Food Quality and Preference 71 (2019). - ISSN 0950-3293 - p. 76 - 86.
Consumer attitude - Duckweed - Fit - Information - Meal - Protein

Duckweed is considered a promising source of protein for human food products due to its high protein content and environmentally friendly production properties. In order to achieve successful inclusion in the diet, duckweed should be presented to consumers in an acceptable way. This paper explores Western consumers’ perceptions towards duckweed as human food and investigates in what contexts duckweed could be acceptable to consumers who are not used to eating it. In a first interview study (N = 10), consumers generally responded positively towards duckweed as human food, although associations with turbid ponds also did come up. According to the respondents, duckweed belonged to the food category vegetables. So, duckweed was considered to fit best in meals where vegetables and greens are expected. In a larger online survey (N = 669), it was confirmed that consumers had a more positive deliberate evaluation of duckweed and were more likely to accept a meal with duckweed if duckweed was applied in a fitting meal. It was also shown that providing information about nutritional and sustainability benefits increased deliberate evaluation and acceptability for fitting meals, but decreased it for non-fitting meals. Automatic evaluations positively influenced deliberate evaluation and acceptability, supporting the ‘yuck’ effect, but they did not differ between the meal applications. The current paper shows that if applied in a meal context that fits with consumer expectations, under the assumption that sensory properties like taste are satisfactory, there appear no major objections from consumers against the introduction of duckweed as human food at a larger scale.

Direct and indirect drivers of change in biodiversity and nature's contributions to people
Sluis, T. van der; Elbakidze, M. ; Hahn, T. ; Zimmermann, N.E. ; Cudlín, P. ; Friberg, N. ; Genovesi, P. ; Helm, A. ; Jonsson, B. ; Lengyel, S. ; Leroy, B. ; Luzzati, T. ; Milbau, A. ; Pérez-Ruzafa, A. ; Roche, P. ; Roy, H. ; Sabyrbekov, R. ; Vanbergen, A. ; Vandvik, V. - \ 2018
In: The regional assessment report on Biodiversity and Ecosystem Services for Europe and Central Asia / Rounsevell, Mark, Fischer, Markus, Torre-Marin Rando, Amor, Mader, André, - p. 390 - 568.
Exploratory stock assessments for North Sea skates using the SPiCT model
Fischer, Simon ; McCully Phillips, Sophy ; Poos, J.J. ; Oliveira, José De; Overzee, H.M.J. van; Ellis, Jim - \ 2018
- 1 p.
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