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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    Understanding variation in food oral processing behaviorof consumers differing in age, gender and ethnicity : a physiological perspective
    Ketel, Eva - \ 2020
    Wageningen University. Promotor(en): M. Stieger; K. de Graaf, co-promotor(en): R. de Wijk. - Wageningen : Wageningen University - ISBN 9789463954952 - 183
    Food security in rural Burkina Faso: The importance of consumption of own-farm sourced food versus purchased food
    Fraval, Simon ; Yameogo, Viviane ; Ayantunde, Augustine ; Hammond, James ; Boer, Imke J.M. De; Oosting, Simon J. ; Wijk, Mark T. Van - \ 2020
    Agriculture & Food Security 9 (2020)1. - ISSN 2048-7010
    Market-orientated agriculture - Nutrition-sensitive interventions - Resilient systems

    Background: The number of undernourished people and the risk of micro-nutrient deficiency remain high in sub-Saharan Africa (SSA). Decades of policy designed to reverse the trends of food insecurity have illustrated that the causal pathways of intervention to end-point outcomes, such as nutrition, are not necessarily straightforward. Utilising proxies for dimensions of food security, this study investigates the relative importance of different pathways to food security in two subtly contrasting communities in the Sahelian and Sudanian Savanna zones of Burkina Faso. Results: In Yatenga province, approximately 31% of households were classified as 'severely food insecure' in the 'lean' period. In contrast, over 84% of households sampled in Seno province were classified as being 'severely food insecure' in the 'lean' period. There were statistically significant associations between food security indicators and off-farm income, farm income and production diversity. The source of income had significantly different associations with diet diversity in the two provinces. In Yatenga province, higher gross farm income in the absence of off-farm income was predicted to result in more diverse diets; in Seno province, however, gross farm income was only predicted to result in more diverse diets when households are also earning off-farm income. Conclusions: Our analysis shows that households were most differentiated by income generating pathways to food security in the 'lean' period. This finding should not detract from the essential role played by home-produced foods in improving food security. Rather, market-orientated agriculture and production for home consumption, as shown by households in this study, can be combined as part of a more resilient livelihood strategy. Policy needs to be targeted towards agro-ecological conditions, as well as socioeconomic factors in order to facilitate improved on-farm income, farm resilience and off-farm employment opportunities.

    Verkenning van de zelf voedselproducerende consument in Almere | Flevo Campus Livecast
    Jansma, Jan-Eelco - \ 2020
    Jan-Eelco Jansma heeft onderzoek gedaan naar inwoners van Almere die ook zelf voedsel produceren: de prosument. De kern van prosumptie is dat consumenten (een deel van) de verantwoordelijkheid gaan overnemen. Stadslandbouw is een van de speerpunten in de nieuwe wijk Oosterwold in Almere; Jan-Albert Blaauw is bezig met een concept om de productie van Oosterwold te vermarkten. Moderatie door Joris Lohman.
    Communicatie van statistische informatie over onzekerheid bij de beheersing van risico’s van wateroverlast
    Poortvliet, P.M. ; Knotters, M. ; Verstoep, Joël ; Wijk, Jiska van; Bergsma, Petra - \ 2020
    Stromingen : vakblad voor hydrologen 26 (2020)2. - ISSN 1382-6069 - p. 1 - 16.
    Onzekerheidsanalyse is niet vanzelfsprekend bij de onderbouwing van beslissingen in het strategisch kwantitatief waterbeheer. Toch is informatie over onzekerheid nuttig, omdat inzicht in risico’s en daaraan gerelateerde kosten en baten bijdraagt aan de doelmatigheid van beslissingen. We onderzochten daarom de rol van statistische informatie over onzekerheid bij strategische beslissingen van waterschappen bij het beheersen van risico’s van wateroverlast: hoe wordt deze informatie gepresenteerd, geïnterpreteerd en benut, en ook of de communicatie over statistisch gekwantificeerde onzekerheid kan worden verbeterd.
    Zorg-sportinitiatieven in de wijk. Wonen en leven in een gezonde wijk. Projectencatalogus Gezonde Wijk
    Mulderij, L.S. ; Verkooijen, K.T. ; Wagemakers, A. - \ 2020
    ZonMw
    Integrale lokale zorg-sportinitiatieven onder de loep: wat is de impact op deelnemers? Wat zijn de werkzame elementen in praktijk en beleid? En hoe wordt een initiatief ook organisatorisch en financieel een succes?
    Modelling food security : Bridging the gap between the micro and the macro scale
    Müller, Birgit ; Hoffmann, Falk ; Heckelei, Thomas ; Müller, Christoph ; Hertel, Thomas W. ; Polhill, J.G. ; Wijk, Mark van; Achterbosch, Thom ; Alexander, Peter ; Brown, Calum ; Kreuer, David ; Ewert, Frank ; Ge, Jiaqi ; Millington, James D.A. ; Seppelt, Ralf ; Verburg, Peter H. ; Webber, Heidi - \ 2020
    Global environmental change : human and policy dimensions 63 (2020). - ISSN 0959-3780
    Agent-based models - Crop models - Economic equilibrium models - Food security - Land use - Model integration - Multi-scale interactions - Social-ecological feedbacks

    Achieving food and nutrition security for all in a changing and globalized world remains a critical challenge of utmost importance. The development of solutions benefits from insights derived from modelling and simulating the complex interactions of the agri-food system, which range from global to household scales and transcend disciplinary boundaries. A wide range of models based on various methodologies (from food trade equilibrium to agent-based) seek to integrate direct and indirect drivers of change in land use, environment and socio-economic conditions at different scales. However, modelling such interaction poses fundamental challenges, especially for representing non-linear dynamics and adaptive behaviours. We identify key pieces of the fragmented landscape of food security modelling, and organize achievements and gaps into different contextual domains of food security (production, trade, and consumption) at different spatial scales. Building on in-depth reflection on three core issues of food security – volatility, technology, and transformation – we identify methodological challenges and promising strategies for advancement. We emphasize particular requirements related to the multifaceted and multiscale nature of food security. They include the explicit representation of transient dynamics to allow for path dependency and irreversible consequences, and of household heterogeneity to incorporate inequality issues. To illustrate ways forward we provide good practice examples using meta-modelling techniques, non-equilibrium approaches and behavioural-based modelling endeavours. We argue that further integration of different model types is required to better account for both multi-level agency and cross-scale feedbacks within the food system.

    De hittebestendige stad : Een koele kijk op de inrichting van de buitenruimte
    Kluck, Jeroen ; Klok, Lisette ; Solcerová, Anna ; Kleerekoper, Laura ; Wilschut, Liesbeth ; Jacobs, Cor ; Loeve, Ronald ; Daniels, E.E. ; Dankers, Rutger - \ 2020
    Amsterdam : Hogeschool van Amsterdam - ISBN 9789492644800 - 128
    openbare ruimte - klimaatadaptatie - warmte - zorg - groene infrastructuur - public space - climate adaptation - heat - care - green infrastructure
    Het klimaat verandert. Het wordt natter en heter. Nederland moet zich aanpassen aan het veranderende klimaat. Daarom staan de gemeenten voor de uitdaging om er vanaf 2020 voor te zorgen dat een (her)inrichting van een straat of wijk klimaatbestendig is. Voor wateroverlast en waterveiligheid weten we ongeveer hoe dat moet. Voor hitte is eigenlijk nog niet duidelijk wat er moet gebeuren. En dat is zorgelijk, want hitte kan grote problemen geven. Hitte kan leiden tot extra sterfte en zal het leven in de stad bovendien steeds vaker onaangenaam maken. Duidelijk is dat er aandacht nodig is op het sociale vlak (o.a. in de zorg), voor gebouwen (koele binnenruimtes) en voor de buitenruimte. Dit rapport richt zich op dat laatste: op het hittebestendig inrichten van de buitenruimte, omdat daar nog veel kennis ontbreekt.
    Towards actionable farm typologies : Scaling adoption of agricultural inputs in Rwanda
    Hammond, Jim ; Rosenblum, Nathaniel ; Breseman, Dana ; Gorman, Léo ; Manners, Rhys ; Wijk, Mark T. van; Sibomana, Milindi ; Remans, Roseline ; Vanlauwe, Bernard ; Schut, Marc - \ 2020
    Agricultural Systems 183 (2020). - ISSN 0308-521X
    Adoption of agricultural innovations - Intensification - Rural development - Scaling - Smallholders - Typologies

    Rollout of development interventions using a one-size-fits-all model can achieve economies of scale but neglects to account for variability in farm and farmer characteristics. A data-driven approach to incorporate farmer diversity in scaling strategies may help to achieve greater development impact. However, interpreting the multiplicity of smallholder characteristics is complex, time-consuming, and the ways in which the insights gained can be implemented is poorly understood. Navigating these tensions, we present a farm typology study carried out in collaboration with a large development organisation (the “scaling partner”) promoting agricultural inputs in Rwanda. This study was conducted late in the scaling pathway, in order to finesse the scaling strategy, rather than to target intervention selection. Drawing on nearly 3000 interviews from 17 districts of the Western, Southern, and Eastern Provinces of Rwanda, the typology differentiates households along two axes: 1. prosperity (a cornerstone of conventional typologies), and 2. adoption of inputs (fertilisers and improved crop varieties). We used an efficient household survey tool, a minimum-variable approach, and concepts from the study of adoption of agricultural innovations. Through an action-research collaboration with the scaling organisation we adapted the methods and the findings to be “actionable. Approximately two-thirds of the study population were using fertilisers and improved seed to some extent. Along each prosperity stratum, however, there were multiple degrees of adoption, demonstrating the value of including adoption information in typology constructions. Ten farm types were identified, where the key differences along the prosperity axis were land area cultivated and livestock owned, and the key differences along the adoption axis were perceptions of input efficacy, access to training, and education level. We also present a simple decision tree model to assign new households to a farm type. The findings were used in three ways by the scaling organisation: (i) characterisation of the population into discrete groups; (ii) prioritisation, of farm types for engagement, and geographical locations for further investment; and (iii) design of decision support tools or re-design of packages to support technology adoption for specific farm types. The need for field-level validation of the typologies was also stressed by the scaling organisation.

    Does the face show what the mind tells? A comparison between dynamic emotions obtained from facial expressions and Temporal Dominance of Emotions (TDE)
    Bommel, Roelien van; Stieger, Markus ; Visalli, Michel ; Wijk, Rene de; Jager, Gerry - \ 2020
    Food Quality and Preference 85 (2020). - ISSN 0950-3293
    Explicit measures - FaceReader™ (FR) - Facial expressions - Implicit measures - Multiple bite assessment - Temporal Dominance of Emotions (TDE)

    Measuring food-evoked emotions dynamically during consumption can be done using explicit self-report methods such as Temporal Dominance of Emotions (TDE), and implicit methods such as recording facial expressions. It is not known whether or how dynamic explicit and implicit emotion measures correspond. This study investigated how explicit self-reported food-evoked emotions evaluated with TDE are related to implicit food-evoked emotions determined from facial expressions. Fifty-six participants evaluated six yogurts with granola pieces varying in size, hardness and concentration, using multiple bite assessment employing TDE for the first, third and fifth bite of consumption. Consumers were video recorded during each bite of consumption and facial expressions were analysed using FaceReader™. Happy, interested, disgusted and bored were similar descriptors measured explicitly and implicitly. Little overlap was observed regarding the type of emotion characterization by FaceReader™ and TDE. Products were mainly discriminated along the valence dimension (positive – negative), and directly reflected product discrimination in terms of liking. FaceReader™ further differentiated the least liked products from each other on arousal and negative facial expressions. Our results indicated little dynamics in food-evoked emotions within and between bites. Facial expressions seemed more dynamic within bites, while explicit food-evoked emotion responses seemed more dynamic between bites. We conclude that FaceReader™ intensities of emotions and dominance durations observed in TDE are not directly comparable and show little overlap. Moreover, food-evoked emotion responses were fairly stable from first to last bite and only very limited changes were observed using implicit and explicit emotions measures.

    Consumer preferences for different formats of personalised nutrition and health services
    Bouwman, Emily ; Dijksterhuis, G.B. ; Hogenelst, Koen ; Reinders, M.J. ; Taufik, D. ; Wijk, R.A. de - \ 2020
    Wageningen University & Research - 60 p.
    Concordance of SNP-and allele-based typing workflows in the context of a large-scale international Salmonella enteritidis outbreak investigation
    Coipan, Claudia E. ; Dallman, Timothy J. ; Brown, Derek ; Hartman, Hassan ; Voort, Menno van der; Berg, Redmar R. van den; Palm, Daniel ; Kotila, Saara ; Wijk, Tom van; Franz, Eelco - \ 2020
    Microbial Genomics 6 (2020)3. - ISSN 2057-5858
    Epidemiology - Hierarchical clustering - Infectious disease - Surveillance - Unsupervised machine learning - Whole-genome sequencing

    A large European multi-country Salmonella enterica serovar Enteritidis outbreak associated with Polish eggs was character-ized by whole-genome sequencing (WGS)-based analysis, with various European institutes using different analysis workflows to identify isolates potentially related to the outbreak. The objective of our study was to compare the output of six of these different typing workflows (distance matrices of either SNP-based or allele-based workflows) in terms of cluster detection and concordance. To this end, we analysed a set of 180 isolates coming from confirmed and probable outbreak cases, which were representative of the genetic variation within the outbreak, supplemented with 22 unrelated contemporaneous S. enterica serovar Enteritidis isolates. Since the definition of a cluster cut-off based on genetic distance requires prior knowledge on the evolutionary processes that govern the bacterial populations in question, we used a variety of hierarchical clustering methods (single, average and complete) and selected the optimal number of clusters based on the consensus of the silhouette, Dunn2, and McClain–Rao internal validation indices. External validation was done by calculating the concordance with the WGS-based case definition (SNP-address) for this outbreak using the Fowlkes–Mallows index. Our analysis indicates that with complete-linkage hierarchical clustering combined with the optimal number of clusters, as defined by three internal validity indices, the six different allele-and SNP-based typing workflows generate clusters with similar compositions. Furthermore, we show that even in the absence of coordinated typing procedures, but by using an unsupervised machine learning methodology for cluster delineation, the various workflows that are currently in use by six European public-health authorities can identify concordant clusters of genetically related S. enterica serovar Enteritidis isolates; thus, providing public-health researchers with compara-ble tools for detection of infectious-disease outbreaks.

    Implementing immersive technologies in consumer testing : Liking and Just-About-Right ratings in a laboratory, immersive simulated café and real café
    Zandstra, E.H. ; Kaneko, D. ; Dijksterhuis, G.B. ; Vennik, E. ; Wijk, R.A. De - \ 2020
    Food Quality and Preference 84 (2020). - ISSN 0950-3293
    Context - Engagement - Immersive technology - Just-About-Right ratings - Liking

    Initial research indicates that the use of immersive technologies may improve the predictive validity and reliability of liking scores in consumer testing. However, how immersive technologies impact Just-About-Right ratings is hardly known. Forty-five participants took part in three tasting sessions, each in a different context: 1) laboratory, 2) immersive context simulating a café using audiovisual cues, and 3) real café. Each session, participants tasted four tomato soups varying in salt content preceded by a warm-up sample. Liking, optimal levels of sensory attributes (JAR) and engagement were measured. Results showed that there were no differences in liking or JAR ratings on sensory attributes of the soups across the three contexts. Nevertheless, participants felt more engaged in the real café and simulated café than in the laboratory. These results contribute to a better understanding of how sensory differences as assessed in a laboratory or immersive context relate to sensory differences that consumers would notice when they use the products in real-life.

    IgE cross-reactivity measurement of cashew nut, hazelnut and peanut using a novel IMMULITE inhibition method
    Bastiaan-Net, Shanna ; Batstra, Manou R. ; Aazamy, Nasrin ; Savelkoul, Huub F.J. ; Valk, Johanna P.M. Van Der; Gerth Van Wijk, Roy ; Schreurs, Marco W.J. ; Wichers, Harry J. ; Jong, Nicolette W. De - \ 2020
    Clinical Chemistry and Laboratory Medicine (2020). - ISSN 1434-6621
    allergy diagnostics - cashew nut - hazelnut - IgE cross-reactivity - IMMULITE technology - peanut

    Tree nut-allergic individuals are often sensitised towards multiple nuts and seeds. The underlying cause behind a multi-sensitisation for cashew nut, hazelnut, peanut and birch pollen is not always clear. We investigated whether immunoglobulin E antibody (IgE) cross-reactivity between cashew nut, hazelnut and peanut proteins exists in children who are multi-allergic to these foods using a novel IMMULITE®-based inhibition methodology, and investigated which allergens might be responsible. In addition, we explored if an allergy to birch pollen might play a role in this co-sensitisation for cashew nut, hazelnut and peanut. Serum of five children with a confirmed cashew nut allergy and suffering from allergic symptoms after eating peanut and hazelnut were subjected to inhibition immunoassays using the IMMULITE® 2000 XPi. Serum-specific IgE (sIgE) to seed storage allergens and pathogenesis-related protein 10 (PR10) allergens were determined and used for molecular multicomponent allergen correlation analyses with observed clinical symptoms and obtained inhibition data. IgE cross-reactivity was observed in all patients. Hazelnut extract was a strong inhibitor of cashew nut sIgE (46.8%), while cashew nut extract was less able to inhibit hazelnut extract (22.8%). Peanut extract showed the least inhibition potency. Moreover, there are strong indications that a birch pollen sensitisation to Bet v 1 might play a role in the observed symptoms provoked upon ingestion of cashew nut and hazelnut. By applying an adjusted working protocol, the IMMULITE® technology can be used to perform inhibition assays to determine the risk of sIgE cross-reactivity between very different food components.

    The Rural Household Multiple Indicator Survey, data from 13,310 farm households in 21 countries
    Wijk, Mark van; Hammond, James ; Gorman, Leo ; Adams, Sam ; Ayantunde, Augustine ; Baines, David ; Bolliger, Adrian ; Bosire, Caroline ; Carpena, Pietro ; Chesterman, Sabrina ; Chinyophiro, Amon ; Daudi, Happy ; Dontsop, Paul ; Douxchamps, Sabine ; Emera, Willy Desire ; Fraval, Simon ; Fonte, Steven ; Hok, Lyda ; Kiara, Henry ; Kihoro, Esther ; Korir, Luke ; Lamanna, Christine ; Long, Chau T.M. ; Manyawu, Godfrey ; Mehrabi, Zia ; Mengistu, Dejene K. ; Mercado, Leida ; Meza, Katherin ; Mora, Vesalio ; Mutemi, Jacob ; Ng’endo, Mary ; Njingulula, Paulin ; Okafor, Chris ; Pagella, Tim ; Phengsavanh, Phonepaseuth ; Rao, James ; Ritzema, Randall ; Rosenstock, Todd S. ; Skirrow, Tom ; Steinke, Jonathan ; Stirling, Clare ; Gabriel Suchini, Jose ; Teufel, Nils ; Thorne, Peter ; Vanek, Steven ; Etten, Jacob van; Vanlauwe, Bernard ; Wichern, Jannike ; Yameogo, Viviane - \ 2020
    Scientific Data 7 (2020)1. - ISSN 2052-4463

    The Rural Household Multiple Indicator Survey (RHoMIS) is a standardized farm household survey approach which collects information on 758 variables covering household demographics, farm area, crops grown and their production, livestock holdings and their production, agricultural product use and variables underlying standard socio-economic and food security indicators such as the Probability of Poverty Index, the Household Food Insecurity Access Scale, and household dietary diversity. These variables are used to quantify more than 40 different indicators on farm and household characteristics, welfare, productivity, and economic performance. Between 2015 and the beginning of 2018, the survey instrument was applied in 21 countries in Central America, sub-Saharan Africa and Asia. The data presented here include the raw survey response data, the indicator calculation code, and the resulting indicator values. These data can be used to quantify on- and off-farm pathways to food security, diverse diets, and changes in poverty for rural smallholder farm households.

    Relating oral physiology and anatomy of consumers varying in age, gender and ethnicity to food oral processing behavior
    Ketel, Eva C. ; Wijk, Rene A. de; Graaf, Cees de; Stieger, Markus - \ 2020
    Physiology and Behavior 215 (2020). - ISSN 0031-9384
    Age - Ethnicity - Gender - Oral anatomy - Oral physiology - Oral processing behavior

    The aim of this study was to link parameters describing oral physiology and anatomy of consumers varying in age, gender and ethnicity to food oral processing behavior. Three groups of healthy consumers were compared: Dutch, Caucasian adults (18–30 yrs, n =32), Chinese, Asian adults (18–30 yrs, n =32) and Dutch, Caucasian older adults (65–85 yrs, n =32). Mastication performance, salivary flow rate (stimulated and unstimulated) and dental status were quantified to characterize oral physiology. Volume of oral cavity, tongue dimensions, facial anthropometry, height and weight were quantified to characterize anatomy. Oral processing behavior of three solid foods (carrot, cheese and sausage) was quantified by video recordings and eating rate (g/s), average consumption time (s), chews per bite (-) and average bite size (g) were determined. Dutch, Caucasian older adults had smaller volume of oral cavity, lower number of teeth and larger head width compared to Dutch, Caucasian adults. Chinese, Asian adults showed significantly higher mastication performance and larger head width compared to Dutch, Caucasian consumers, while dental status did not significantly differ between groups. Males had significantly larger volumes of oral cavity and larger head height and width compared to females. Dutch, Caucasian adults had a shorter average consumption time (s), less chews per bite and consumed the three foods with higher eating rate (g/s) compared to Dutch, Caucasian older adults. Chinese, Asian adults had a significantly longer average consumption time (s), more chews per bite, smaller average bite size (g) and lower eating rate (g/s) compared to Dutch, Caucasian adults. Twenty-one significant relationships were found between oral physiological and anatomical parameters and oral processing behavior. Body weight resulted in the largest β-values, indicating to be the anatomical parameter of largest influence on oral processing behavior. We conclude that only few oral physiological and anatomical parameters related with food oral processing behavior. We suggest that other factors, including cultural factors contribute to variation in food oral processing behavior between different consumer groups more than saliva flow, volume of oral cavity, mastication performance and dental status.

    The Rural Household Multiple Indicator Survey (RHoMIS) data of 13,310 farm households in 21 countries
    Wijk, Mark van; Hammond, James ; Gorman, Leo ; Adams, Sam ; Ayantunde, Augustine ; Baines, David ; Bolliger, Adrian ; Bosire, Caroline ; Carpena, Pietro ; Chesterman, Sabrina ; Chinyophiro, Amon ; Daudi, Happy ; Dontsop, Paul ; Douxchamps, Sabine ; Emera, Willy Desire ; Fraval, Simon ; Fonte, Steven ; Hok, Lyda ; Kiara, Henry ; Kihoro, Esther ; Korir, Luke ; Lamanna, Christine ; Long, Chau T.M. ; Manyawu, Godfrey ; Mehrabi, Zia ; Mengistu, Dejene K. ; Mercado, Leida ; Meza, Katherin ; Mora, Vesalio ; Mutemi, Jacob ; Ng’endo, Mary ; Njingulula, Paulin ; Okafor, Chris ; Pagella, Tim ; Phengsavanh, Phonepaseuth ; Rao, James ; Ritzema, Randall ; Rosenstock, Todd S. ; Skirrow, Tom ; Steinke, Jonathan ; Stirling, Clare ; Gabriel Suchini, Jose ; Teufel, Nils ; Thorne, Peter ; Vanek, Steven ; Etten, Jacob van; Vanlauwe, Bernard ; Wichern, Jannike ; Yameogo, Viviane - \ 2019
    International Livestock Research Institute (ILRI)
    household surveys - food security - smallholders - agriculture
    The Rural Household Multiple Indicator Survey (RHoMIS) is a standardized farm household survey approach which collects information on 753 variables covering household demographics, farm area, crops grown and their production, livestock holdings and their production, agricultural product use and variables underlying standard socio-economic and food security indicators like the Poverty Probability Index, the Household Food Insecurity Access Scale and dietary diversity. These variables are used to quantify more than 40 different aggregate indicators on farm household characteristics, welfare, productivity and economic performance. Between 2015 and the beginning of 2018, the survey instrument has been applied in 21 countries in Central America, sub-Saharan Africa and Asia. The data presented here cover the raw data, the indicator calculation code and the resulting indicator values, and can be used to quantify on- and off-farm pathways to food security, diverse diets and reduced poverty of rural smallholder farm households.
    Experiences and Drivers of Food Insecurity in Guatemala's Dry Corridor: Insights From the Integration of Ethnographic and Household Survey Data
    Beveridge, Louise ; Whitfield, Stephen ; Fraval, Simon ; Wijk, Mark van; Etten, Jacob van; Mercado, Leida ; Hammond, James ; Davila Cortez, Luz ; Gabriel Suchini, Jose ; Challinor, Andrew - \ 2019
    Frontiers in Sustainable Food Systems 3 (2019). - ISSN 2571-581X
    agriculture - Central America - climate - ethnography - food security - household survey - participatory - underlying drivers

    Eradicating hunger is a complex and multifaceted challenge, requiring evidence bases that can inform wide scale action, but that are also participatory and grounded to have local relevance and effectiveness. The Rural Household Multi-Indicator Surveys (RHoMIS) provides a broad assessment of household capabilities and food security outcomes, while ethnographic approaches evidence how individuals' perceptions, experiences and local socio-political context shape food security experiences and intervention outcomes. However, integrating these research approaches presents methodological and ontological challenges. We combine a quantitative approach with life history interviews to understand the drivers, experiences and outcomes of food insecurity in Guatemala's dry corridor region. We also reflect on the effectiveness and challenges of integrating the two methods for purposes of selective sampling, triangulating evidence, and producing a cohesive analyses of food insecurity in the region. Variables with a statistically significant association with severe food insecurity in the region are: coffee cultivation (when market participation is low), dependence on agricultural labor income, and poverty level. Drivers of food insecurity experiences most commonly identified by participants are: consecutive drought; ill health and displacement of income for medicine; social marginalization; high start-up costs in production; absence or separation of a household head; and a lack of income and education opportunity. Ethnographic approaches identify a broader range of drivers contributing to food insecurity experiences, and add explanatory power to a statistical model of severe food insecurity. This integrated analysis provides a holistic picture of food insecurity in Guatemala's dry corridor region.

    Food Access Deficiencies in Sub-saharan Africa: Prevalence and Implications for Agricultural Interventions
    Fraval, Simon ; Hammond, James ; Bogard, Jessica R. ; Ng'endo, Mary ; Etten, Jacob van; Herrero, Mario ; Oosting, Simon J. ; Boer, Imke J.M. de; Lannerstad, Mats ; Teufel, Nils ; Lamanna, Christine ; Rosenstock, Todd S. ; Pagella, Tim ; Vanlauwe, Bernard ; Dontsop-Nguezet, Paul M. ; Baines, David ; Carpena, Pietro ; Njingulula, Paulin ; Okafor, Christopher ; Wichern, Jannike ; Ayantunde, Augustine ; Bosire, Caroline ; Chesterman, Sabrina ; Kihoro, Esther ; Rao, Elizaphan J.O. ; Skirrow, Tom ; Steinke, Jonathan ; Stirling, Clare M. ; Yameogo, Viviane ; Wijk, Mark T. van - \ 2019
    Frontiers in Sustainable Food Systems 3 (2019). - ISSN 2571-581X
    Bayesian - crops - diet diversity - farm systems - livestock - nutrition-sensitive - rural development

    Our understanding of food security in sub-Saharan Africa (SSA) has been hampered by limitations in the temporal and spatial representativeness of data. Food balance sheets provide scalable estimates of per capita food availability, but fail to represent food access, stability and their causal linkages. In contrast, rural household surveys represent detailed conditions for one or multiple points in time, but are influenced by survey timing and are often limited in geographical coverage. This study draws on a large sample of rural land-holding households in SSA (n = 6,353) to identify household level food access deficiencies and to understand the associations with rural livelihoods and food sourcing behavior throughout the year. Food access deficiencies were identified using food security of access and diet diversity indicators. Dietary diversity and channel of access (farm or purchased) were enumerated for the “flush” and “lean” periods and food security of access was enumerated for the lean period only - making the results of this study independent of survey timing. As many as 39% of households were classified as severely food insecure (in terms of food access) and as many as 49% of households were likely to be deficient in micronutrients in the lean period. Vulnerability to food insecurity and micronutrient deficiencies differed by household composition, agricultural livelihood characteristics and agro-ecological zone. Dairy, fruit and vitamin A-rich produce were predominantly accessed through the farm channel. Households with a livestock component to their farm had a lower prevalence of severe food insecurity and higher diet diversity scores. These findings have implications for the development of nutrition-sensitive and nutrition-specific interventions. Interventions need to be tailored to agro-ecological zone, household composition, scale of operation and production mix. Increasing income will not necessarily result in improved diet diversity or healthy dietary choices. Interventions focused on income generation should monitor and promote crop and livestock production diversity and provide nutrition education.

    Implementing immersive technologies in consumer testing: Taste perception and liking in a laboratory, immersive simulated café and real café
    Dijksterhuis, G.B. ; Kaneko, D. ; Wijk, R.A. de; Zoggel, M. van; Schiona, Irene ; Zandstra, E.H. - \ 2019
    Implementing immersive technologies in consumer testing: Taste perception and liking in a laboratory, immersive simulated café and real café
    Zandstra, Liesbeth ; Kaneko, D. ; Dijksterhuis, G.B. de; Vennik, E. van; Wijk, R.A. de; Zandstra, E.H. - \ 2019
    Food perception and emotion measured over time in-lab and in-home
    Wijk, R.A. De; Kaneko, D. ; Dijksterhuis, G.B. ; Zoggel, M. van; Schiona, I. ; Visalli, M. ; Zandstra, Liesbeth - \ 2019
    Eating context - Facial expressions - Heart rate - Repeated sensory tests
    Background: Real-life human eating behaviour does not take place in a vacuum, rather it happens in context. The context in which consumers eat their foods influences the acceptance of the consumed foods. Consequently, consumers’ hedonic and sensory ratings elicited in a natural consumption context will differ from those elicited under controlled sensory laboratory conditions. Moreover, foods are rarely consumed on one single occasion but are typically consumed repeatedly and ratings may change over repeated consumptions as well. Often, consumer acceptance is tested explicitly, for example with liking ratings, especially when the testing is done outside the laboratory. Implicit tests such as facial expressions and physiological measurements of the autonomic nervous system can provide additional information on consumer acceptance. As a result of technological advantages, such tests are no longer limited to the laboratory but can also be used in natural consumption contexts. Method: Eighteen healthy Dutch consumers (18–65 years of age) tested four test foods plus a warm-up sample ten times on consecutive weekdays and on similar hours using their own laptop and webcam. Test locations alternated between the sensory laboratory and the participant's own home. Explicit measures included liking scores and scores on ten sensory taste/flavour/texture attributes, and implicit measures included facial expressions, heart rate and consumption duration using Face Reader TM . This study was the first to validate the Face Reader TM for usage at home. Results: The liking scores and sensory profiles varied between test foods (p < 0.05), but not between test locations and only some specific sensory attributes showed systematic variation over repeated consumption. In contrast, implicit measures showed systematic effects of test foods, test locations, and repeated consumptions (p < 0.05). Compared to consumption in the laboratory, consumption at home was faster, triggered higher heart rates, and triggered more intense facial expressions of happiness, contempt, disgust and boredom. Conclusions: Implicit tests were more sensitive to effects of test location and repeated consumption than explicit tests. Additional research is required to investigate the relevance of these measures to long term consumer acceptance of food products.
    Effects of eating context on food perception are not caused by the eating location itself
    Dijksterhuis, G.B. ; Kaneko, D. ; Wijk, R.A. de; Zoggel, M. van; Schiona, Irene ; Zandstra, Liesbeth - \ 2019
    Effects of eating context on food perception are not caused by the eating location itself
    Dijksterhuis, G.B. ; Kaneko, D. ; Wijk, R.A. de; Zoggel, M. van; Schiona, Irene ; Zandstra, E.H. - \ 2019
    PPS-project onderzoekt effect omgeving op voedselgewoonten
    Wijk, Rene de; Dijksterhuis, Garmt - \ 2019
    Impact of on-pack visual cues on household premeditated food waste
    Janssen, A.M. ; Bos-Brouwers, H.E.J. ; Schnabel, S.K. ; Wijk, R.A. de; Tromp, S.O. - \ 2019
    Gezonde Wijk en SEGV Lokale aanpak
    Mulderij, Lisanne ; Wagemakers, Annemarie - \ 2019
    Gezonde Wijk
    Mulderij, Lisanne ; Verkooijen, Kirsten - \ 2019
    Minder ADHD in groene wijk
    Vries, S. de - \ 2019
    In wijken met meer groen gebruiken minder kinderen ADHD-medicatie, blijkt uit Wagenings onderzoek. Dit geldt vooral voor armere wijken. Ook zijn de verschillen in mentale gezondheid tussen mensen met lagere en hogere inkomens aanzienlijk kleiner in een groene woonomgeving dan wanneer de woonomgeving minder groen is. Met adviezen aan overheden, projectontwikkelaars en stedenbouwkundigen dragen Wageningse onderzoekers bij aan een gezondere leefomgeving. Denk je dat we meer kunnen investeren in groen voor onze gezondheid?

    Schone wiet telen: deze onderzoeker bewijst dat het kan
    Poot, E.H. - \ 2019
    A perspective on water quality in connected systems: modelling feedback between upstream and downstream transport and local ecological processes
    Teurlincx, Sven ; Wijk, Dianneke van; Mooij, Wolf M. ; Kuiper, Jan J. ; Huttunen, Inese ; Brederveld, Robert J. ; Chang, Manqi ; Janse, Jan H. ; Woodward, Ben ; Hu, Fenjuan ; Janssen, Annette B.G. - \ 2019
    Current Opinion in Environmental Sustainability 40 (2019). - ISSN 1877-3435 - p. 21 - 29.

    Food production for a growing world population relies on application of fertilisers and pesticides on agricultural lands. However, these substances threaten surface water quality and thereby endanger valued ecosystem services such as drinking water supply, food production and recreational water use. Such deleterious effects do not merely arise on the local scale, but also on the regional scale through transport of substances as well as energy and biota across the catchment. Here we argue that aquatic ecosystem models can provide a process-based understanding of how these transports by water and organisms as vectors affect – and are affected by – ecosystem state and functioning in networks of connected lakes. Such a catchment scale approach is key to setting critical limits for the release of substances by agricultural practices and other human pressures on aquatic ecosystems. Thereby, water and food production and the trade-offs between them may be managed more sustainably.

    Integrated modelling and management of water resources: the ecosystem perspective on the nexus approach
    Hülsmann, Stephan ; Sušnik, Janez ; Rinke, Karsten ; Langan, Simon ; Wijk, Dianneke van; Janssen, Annette B.G. ; Mooij, Wolf M. - \ 2019
    Current Opinion in Environmental Sustainability 40 (2019). - ISSN 1877-3435 - p. 14 - 20.

    Addressing challenges of water, energy and food security, nexus approaches towards resources management are being developed and starting to be implemented. However, the ecosystem perspective, essential for sustainable resources management, has been identified as a missing element within earlier nexus assessments. With regard to water they have mainly focused on the allocation to different sectors and users, while ecosystem services were rarely explicitly addressed. Existing aquatic ecosystem models are capable of quantifying a wide range of ecosystem services, but have thus far not been comprehensively used in a nexus context. Recent developments in aquatic ecosystem modelling approaches provide opportunities to achieve the sought integration of ecosystem services in the nexus approach. Therefore, we argue for a stronger role of aquatic ecosystem models in nexus assessments.

    A Generically Parameterized model of Lake eutrophication (GPLake) that links field-, lab- and model-based knowledge
    Chang, Manqi ; Teurlincx, Sven ; DeAngelis, Donald L. ; Janse, Jan H. ; Troost, Tineke A. ; Wijk, Dianneke van; Mooij, Wolf M. ; Janssen, Annette B.G. - \ 2019
    Science of the Total Environment 695 (2019). - ISSN 0048-9697
    Consumer-resource interactions - Nutrient versus light limitation - PCLake - Phytoplankton - Vollenweider - Water quality management

    Worldwide, eutrophication is threatening lake ecosystems. To support lake management numerous eutrophication models have been developed. Diverse research questions in a wide range of lake ecosystems are addressed by these models. The established models are based on three key approaches: the empirical approach that employs field surveys, the theoretical approach in which models based on first principles are tested against lab experiments, and the process-based approach that uses parameters and functions representing detailed biogeochemical processes. These approaches have led to an accumulation of field-, lab- and model-based knowledge, respectively. Linking these sources of knowledge would benefit lake management by exploiting complementary information; however, the development of a simple tool that links these approaches was hampered by their large differences in scale and complexity. Here we propose a Generically Parameterized Lake eutrophication model (GPLake) that links field-, lab- and model-based knowledge and can be used to make a first diagnosis of lake water quality. We derived GPLake from consumer-resource theory by the principle that lacustrine phytoplankton is typically limited by two resources: nutrients and light. These limitations are captured in two generic parameters that shape the nutrient to chlorophyll-a relations. Next, we parameterized GPLake, using knowledge from empirical, theoretical, and process-based approaches. GPLake generic parameters were found to scale in a comparable manner across data sources. Finally, we show that GPLake can be applied as a simple tool that provides lake managers with a first diagnosis of the limiting factor and lake water quality, using only the parameters for lake depth, residence time and current nutrient loading. With this first-order assessment, lake managers can easily assess measures such as reducing nutrient load, decreasing residence time or changing depth before spending money on field-, lab- or model- experiments to support lake management.

    Wageningen University meet hitte boven Amsterdam met weerballon
    Steeneveld, G.J. ; Heusinkveld, B.G. - \ 2019

    Onderzoekers van Wageningen University lieten woensdag meerdere weerballonnen op vanaf de Dam in Amsterdam. Het uiteindelijke doel: een weerbericht per wijk.

    Household-level drivers of dietary diversity in transitioning agricultural systems : Evidence from the Greater Mekong Subregion
    Ritzema, R.S. ; Douxchamps, S. ; Fraval, S. ; Bolliger, A. ; Hok, L. ; Phengsavanh, P. ; Long, C.T.M. ; Hammond, J. ; Wijk, M.T. van - \ 2019
    Agricultural Systems 176 (2019). - ISSN 0308-521X
    Agricultural transition - Cambodia - Dietary diversity - Greater Mekong Subregion - Household Dietary Diversity Score - Laos - Vietnam

    Over the past four decades, agricultural systems in the Greater Mekong Subregion (GMS) have largely evolved from a subsistence orientation toward commercial production, but the multi-faceted changes behind this evolution vary in substance and degree. Despite connoting economic progress, effects of these changes on household welfare indicators such as dietary diversity have been unclear. By taking a comprehensive view of the farm household, this study discerns the drivers of household dietary diversity in this transitional context by linking the Household Dietary Diversity Score (HDDS), as an indicator of dietary diversity, to key household characteristics, livelihood strategies and indicators of farm performance in three study sites in Cambodia, Laos and Vietnam. The Rural Household Multi-Indicator Survey (RHoMIS) tool, a combined survey and analysis platform, was employed to collect data from over 1300 farm households. HDDS is found to increase among the sites in a way that is roughly associated with their state of agricultural transition, though differing combinations of market orientation, specialisation, and intensification traits that describe such a transition suggest that the pathway to commercialisation, and dietary diversity, is not a linear one. Drivers of dietary diversity vary markedly between the sites. In the Laos site, HDDS is most closely correlated to a set of variables closely linked with agricultural transition, while in the Cambodia site it is associated more with other farm and household characteristics. In the Vietnam site, dietary diversity is correlated to the overall value of crop production. Findings point to the need to contextualise site-specific knowledge of linkages between dietary diversity and ongoing agricultural transition in the GMS, as well as policy and interventions seeking to improve dietary diversity in the face of such transition.

    Vulnerability and adaptation options to climate change for rural livelihoods – A country-wide analysis for Uganda
    Wichern, Jannike ; Descheemaeker, Katrien ; Giller, Ken E. ; Ebanyat, Peter ; Taulya, Godfrey ; Wijk, Mark T. van - \ 2019
    Agricultural Systems 176 (2019). - ISSN 0308-521X
    Crop suitability - East Africa - Household food security - Impact assessment - Multi-level

    Rural households in sub-Saharan Africa earn a substantial part of their living from rain-fed smallholder agriculture, which is highly sensitive to climate change. There is a growing number of multi-level assessments on impacts and adaptation options for African smallholder systems under climate change, yet few studies translate impacts at the individual crop level to vulnerability at the household level, at which other livelihood activities need to be considered. Further, these assessments often use representative household types rather than considering the diversity of households for the identification of larger-scale patterns at sub-national and national levels. We developed a framework that combines crop suitability maps with a household food availability analysis to quantify household vulnerability to climate-related impacts on crop production and effects of adaptation options. The framework was tested for Uganda, identifying four hotspots of household vulnerability across the country. Hotspots were visually identified as areas with a relatively high concentration of vulnerable households, experiencing a decline in household crop suitability. About 30% of the households in the hotspots in (central) southwest were vulnerable to a combination of 3 °C temperature increase and 10% rainfall decline through declining suitability for several key crops (including highland banana, cassava, maize and sorghum). In contrast only 10% of the households in West Nile and central northern Uganda were negatively affected, and these were mainly affected by declining suitability of common beans. Households that depended on common beans and lived at lower elevations in West Nile and central north were vulnerable to a 2 to 3 °C temperature increase, while households located at higher elevations (above 1100–2000 m.a.s.l. depending on the crop) benefited from such an increase. Options for adaptation to increasing temperatures were most beneficial in northern Uganda, while drought-related adaptation options were more beneficial in the southwest. This framework provides a basis for decision makers who need information on where the vulnerable households are, what crops drive the vulnerability at household level and which intervention efforts are most beneficial in which regions.

    On the communication of statistical information about uncertainty in flood risk management
    Poortvliet, P.M. ; Knotters, Martin ; Bergsma, Petra ; Verstoep, Joël ; Wijk, Jiska van - \ 2019
    Safety Science 118 (2019). - ISSN 0925-7535 - p. 194 - 204.
    Decision analysis - Flood risk management - Risk communication - Uncertainty

    Uncertainty analysis is not typically performed in hydrological and hydraulic modelling. This is problematic because this may lead to inefficient decision making in water management. We therefore explored the role of statistical knowledge on uncertainty in decision-making processes in long term flood risk management within the context of regional water boards in the Netherlands. Research questions were: (1) in which parts of flood risk management statistical information about uncertainty is presented to professionals of district water boards, and in which forms?; (2) how is this information interpreted and used by these professionals, and how does this influence decision-making processes in district water boards?; and (3) how can communication about statistically quantified uncertainty be improved? To answer these questions we conducted interviews and surveys among professionals and board members of Dutch district water boards. Results suggest that statistical information on uncertainty is hard to interpret by professionals. The amount of statistical information on uncertainty strongly reduces during the decision making process, during which the information transforms from quantitative to qualitative. As a result the statistical information on uncertainty is not utilized to solve flood risk management decision problems. These decision problems are not formulated within statistical frameworks for decision making, and statistical information on uncertainty is not collected and presented with the purpose to be input of such frameworks. Practical recommendations for long term flood risk management are discussed.

    Food security in a changing world : disentangling the diversity of rural livelihood strategies across Uganda
    Wichern, Jannike - \ 2019
    Wageningen University. Promotor(en): K.E. Giller, co-promotor(en): K.K.E. Descheemaeker; Mark T. van Wijk. - Wageningen : Wageningen University - ISBN 9789463439411 - 224

    Climate change increasingly challenges smallholder farming and our ability to achieve Sustainable Development Goal 2 (Zero Hunger) in sub-Saharan Africa. Agricultural interventions are needed that aim at improving the food insecurity of the most vulnerable rural households. Interventions must fit the local context of a diverse population of rural households, and a key challenge is to identify which kinds of interventions work in which regions and for which households. Micro-level information can account for this diversity, but is an underused source of information for planning of interventions at national and sub-national levels.

    In this thesis, I explored how micro-level information from cross-country household survey data can be used for effective planning of interventions. A further research aim was to understand within-country patterns of livelihood strategies in relation to food security and vulnerability to climate change of rural households in Uganda. Cross-country household data from the World Bank Living Standard Measurement Survey – Integrated Surveys on Agriculture (LSMS-ISA) were used to 1) aggregate household level information to higher levels (e.g. districts, regions, livelihood zones), 2) spatially interpolate household level information and 3) identify hotspot areas of household vulnerability. I used data that I collected from two sites in Uganda for an in-depth analysis on current coping strategies of households for climate and price variability. Household food security was approximated using a food availability indicator that quantified the contribution of livelihood activities to household food availability.

    Livelihood strategies of rural households across Uganda varied with household food availability. They changed from subsistence-oriented on-farm activities to market-oriented on-farm and off-farm activities as household food availability increased. Aggregation revealed spatial differences in food availability and livelihood activities. However, a geostatistical interpolation approach showed that local variability in food availability and livelihood activities was often larger than variability across larger areas. These findings stress that the large diversity in livelihood activities within any given area must be recognised in decision making at higher levels.

    Climate change scenarios were linked to the household livelihood activities to identify hotspot areas of vulnerable households in a country-wide assessment of climate change impacts on crop suitability. Groups of crop-related adaptation options were determined per hotspot area. Adaptation options related to temperature were suitable in the north, while drought-related adaptation options were more suitable in the southwest of Uganda. An in-depth analysis indicated that few ex-ante coping strategies were applied under current climate and price variability. Such coping strategies mostly required little financial investment such as switching crops, which was common for households with more land available. Households tended to react to shocks rather than taking preventive action. Better-off households compensated for crop losses by selling livestock or relying more on off-farm income, while the poor and food insecure lacked the resources to do so. These findings suggest that lack of resources can prevent households from adapting to climate change, even when adaptation options are useful from an agronomic perspective. Therefore, contextualised research is needed to understand local barriers to adoption, so that adaptation options can be tailored to local contexts and underpinned by enabling policies and institutional arrangements.

    Current top-down approaches to planning interventions ignore local diversity of livelihood strategies and food security. However, my results demonstrate that food security and vulnerability tend to be locally driven with large variability at small scale. Therefore, I propose a three-step approach for using micro-level information for multi-level planning. Step 1 disentangles livelihood diversity using cross-country household surveys. Step 2 locates important production activities (Pathway 2a) or vulnerable households and suitable adaptation options (Pathway 2b). Step 3 uses site-specific household surveys to assess which interventions work for which groups of households in the local context. This approach adds to existing approaches by generating spatially-explicit and quantitative information on livelihood activities for food availability and on household vulnerability, while accounting for the diversity of households within and across areas. It enables the exploration and tailoring of intervention options under different future scenarios. In this way, my work contributes to identifying pathways to achieve zero hunger by 2030 in sub-Saharan Africa.

    Success of lake restoration depends on spatial aspects of nutrient loading and hydrology
    Janssen, Annette B.G. ; Wijk, Dianneke van; Gerven, Luuk P.A. van; Bakker, Elisabeth S. ; Brederveld, Robert J. ; DeAngelis, Donald L. ; Janse, Jan H. ; Mooij, Wolf M. - \ 2019
    Science of the Total Environment 679 (2019). - ISSN 0048-9697 - p. 248 - 259.
    Alternative stable states - Diffuse source - Management - PCLake - Point source - Spatial heterogeneity

    Many aquatic ecosystems have deteriorated due to human activities and their restoration is often troublesome. It is proposed here that the restoration success of deteriorated lakes critically depends on hitherto largely neglected spatial heterogeneity in nutrient loading and hydrology. A modelling approach is used to study this hypothesis by considering four lake types with contrasting nutrient loading (point versus diffuse)and hydrology (seepage versus drainage). By comparing the longterm effect of common restoration measures (nutrient load reduction, lake flushing or biomanipulation)in these four lake types, we found that restoration through reduction of nutrient loading is effective in all cases. In contrast, biomanipulation only works in seepage lakes with diffuse nutrient inputs, while lake flushing will even be counterproductive in lakes with nutrient point sources. The main conclusion of the presented analysis is that a priori assessment of spatial heterogeneity caused by nutrient loading and hydrology is essential for successful restoration of lake ecosystems.

    Food security in rural sub-Saharan Africa : a household level assessment of crop-livestock systems
    Fraval, Simon - \ 2019
    Wageningen University. Promotor(en): I.J.M. de Boer, co-promotor(en): S.J. Oosting; M.T. van Wijk. - Wageningen : Wageningen University - ISBN 9789463435734 - 179

    Members of rural households in sub-Saharan Africa (SSA) are both vulnerable to the health burdens that stem from food insecurity and central to improving the availability and affordability of wholesome foods. It has been estimated that chronic and hidden hunger can be alleviated by implementing a suite of nutrition-specific interventions at a cost of US\$9.6 billion per annum. This can be accelerated with complementary food system-based interventions. However, such interventions are hampered by a limited understanding of food security status and its associations with rural livelihoods. Therefore, the primary objective of this thesis was to describe, analyse and understand food security in rural landholding households in predominantly mixed crop-livestock agricultural systems of sub-Saharan Africa (SSA). The secondary objective was to improve the methodological basis of household level food security studies.

    The rural household multi-indicator survey (RHOMIS) tool was developed to describe and analyse the circumstances of rural households. The RHOMIS tool aims to adhere to the principles of being time-efficient, utilitarian, user-friendly, flexible and reliable. The credibility, consistency and reliability of data collected using three different farm household surveys. The shorter and more targeted survey tool, RHOMIS, performed better in terms of staying within credible bounds. Measurements of maize yields and land area owned were found to be less reliable than other variables. Despite the limitations in data quality, our analysis shows that if the same farm households are followed over time, the sample sizes needed to detect substantial changes are in the order of hundreds of surveys, and not in the thousands.

    The RHOMIS tool was then used to quantify changes in livelihoods and food security status in an urban linked, high potential region of Tanzania. Households in the study site adaptively responded to local and national circumstances. Changes in land ownership, livestock-holdings and high value crop production were most likely related to market opportunities and personal circumstances, rather than to direct interventions. Several households made strategic changes by expanding land ownership, planting perennial crops and investing in exotic cattle breeds; many households tactically utilised their land for diversified, mixed crop-livestock production. A central finding of this study is that the complex risk management strategies and market responsiveness demonstrated by the `Rising' clusters are at odds with single focus activities that external organisations tend to promote.

    Subsequently, instances of chronic and hidden hunger were analysed in two provinces of Burkina Faso. The results of this study show that in both provinces, the ability to purchase food is what differentiates the more food secure households from their less food secure counterparts. This finding does not detract from the utility of subsistence production -- where consumption of own-farm sourced food catered for between 72\% and 91\% of the annual energy requirements. Further, households were observed to be pursuing market-oriented strategies in combination with production diversification -- likely to reduce risk exposure to climatic or economic shocks.

    In a large sample of households across SSA, we found that as many as 40\% of households were classified as chronically hungry in the lean period. Prevalence of micronutrient dietary gaps were high, ranging from 35\% of households to 68\%. Vulnerability to dietary gaps differed by household composition, livelihood characteristics and agro-ecological zone (AEZ). It is the combination of livelihood characteristics and the agro-ecological production potential that drive the availability of food and income. It was found that households fail to purchase food categories that nutritionally complement their own agricultural products. Furthermore, households with a livestock component to their farm were found to have a lower prevalence of chronic and hidden hunger.

    In extended analyses, the gender of household head and stage of life were found to be associated with the number of household inhabitants and thus influence nutritional requirements and food security status throughout the year. The high prevalence of food insecurity, the complexity of associations and the failure to nutritionally complement own-production with purchases have implications for developing effective interventions. Programs can be designed as `packages' of agricultural and non-agricultural interventions to maximise adoption and maximise the positive impact on food and nutrition security throughout the year.

    Food perception and emotion measured over time in-lab and in-home
    Wijk, R.A. De; Kaneko, D. ; Dijksterhuis, G.B. ; Zoggel, M. van; Schiona, I. ; Visalli, M. ; Zandstra, E.H. - \ 2019
    Food Quality and Preference 75 (2019). - ISSN 0950-3293 - p. 170 - 178.
    Eating context - Facial expressions - Heart rate - Repeated sensory tests
    Background: Real-life human eating behaviour does not take place in a vacuum, rather it happens in context. The context in which consumers eat their foods influences the acceptance of the consumed foods. Consequently, consumers’ hedonic and sensory ratings elicited in a natural consumption context will differ from those elicited under controlled sensory laboratory conditions. Moreover, foods are rarely consumed on one single occasion but are typically consumed repeatedly and ratings may change over repeated consumptions as well. Often, consumer acceptance is tested explicitly, for example with liking ratings, especially when the testing is done outside the laboratory. Implicit tests such as facial expressions and physiological measurements of the autonomic nervous system can provide additional information on consumer acceptance. As a result of technological advantages, such tests are no longer limited to the laboratory but can also be used in natural consumption contexts. Method: Eighteen healthy Dutch consumers (18–65 years of age) tested four test foods plus a warm-up sample ten times on consecutive weekdays and on similar hours using their own laptop and webcam. Test locations alternated between the sensory laboratory and the participant's own home. Explicit measures included liking scores and scores on ten sensory taste/flavour/texture attributes, and implicit measures included facial expressions, heart rate and consumption duration using Face Reader TM . This study was the first to validate the Face Reader TM for usage at home. Results: The liking scores and sensory profiles varied between test foods (p < 0.05), but not between test locations and only some specific sensory attributes showed systematic variation over repeated consumption. In contrast, implicit measures showed systematic effects of test foods, test locations, and repeated consumptions (p < 0.05). Compared to consumption in the laboratory, consumption at home was faster, triggered higher heart rates, and triggered more intense facial expressions of happiness, contempt, disgust and boredom. Conclusions: Implicit tests were more sensitive to effects of test location and repeated consumption than explicit tests. Additional research is required to investigate the relevance of these measures to long term consumer acceptance of food products.
    Food security in rural sub-Saharan Africa: a household level assessment
    Fraval, S. ; Oosting, S.J. ; Boer, I.J.M. de; Lannerstad, Mats ; Wijk, M.T. van - \ 2019
    In: Trade-offs in Science - Keeping the Balance. - Wageningen University & Research - p. 14 - 14.
    Rural households in sub-Saharan Africa (SSA) are both vulnerable to the health burdens that stem from food insecurity and central to improving the availability and affordability of food. In order to understand the occurrence of food insecurity in rural landholding households, this study draws on 6,353 Household interviews, conducted in eight SSA countries. Multiple indicators of food security were enumerated alongside farm and socio-economic variables. As many as 38% of households were classified as chronically hungry in the months of food scarcity. Prevalence of micronutrient dietary gaps were high, ranging from 40% of households lacking daily sources of vitamin B6, to 73% lacking daily sources of calcium. Chronic and hidden hunger were associated with market participation, livestock product diversity, crop product diversity and gross income, where the direction of association differed by agro-ecological zone (AEZ). These livelihood characteristics – in isolation – had limited impact on food security indicators. Rather, it is the combination of these livelihood characteristics and AEZ that drive food security status throughout the year.The high prevalence of food insecurity and the complexity of associations have implications for developing effective nutrition specific and nutrition sensitive interventions. Interventions need to be tailored to agroecological zone, household composition, scale of operation and production mix. Increasing income will not necessarily result in improved diet diversity or healthy dietary choices. Interventions focused on income generation can maximise nutritional impact by promoting crop and livestock production diversity and by providing nutrition education.
    Age, gender, ethnicity and eating capability influence oral processing behaviour of liquid, semi-solid and solid foods differently
    Ketel, Eva C. ; Aguayo-Mendoza, Monica G. ; Wijk, René A. de; Graaf, Cees de; Piqueras-Fiszman, Betina ; Stieger, Markus - \ 2019
    Food Research International 119 (2019). - ISSN 0963-9969 - p. 143 - 151.
    Age - Eating capability - Ethnicity - Gender - Inter-individual variation - Oral processing

    Food oral processing depends on food properties and consumer characteristics. The aim of this study was to determine the effect of age, gender, ethnicity and eating capability on oral processing behaviour of liquid, semi-solid and solid foods. Oral processing behaviour of 18 commercially available foods, ranging from liquids, semi-solids to solids, was compared between Dutch, Caucasian adults (18-30 yrs), Chinese, Asian adults (18-30 yrs), Dutch, Caucasian elderly (60-80 yrs), and consumers with mild swallowing problems and/or low mastication efficiency (18-80 yrs). Participants were video recorded during food consumption and six oral processing parameters extracted. Elderly consumed all foods with lower eating rates (g/s) than young adults by increasing consumption time (s). Females consumed solid foods with lower eating rates (g/s) than males by reducing bite size (g). Chinese, Asian consumers consumed liquid and solid foods with lower eating rates (g/s) than Dutch, Caucasian consumers by reducing bites size (g). Chinese, Asian consumers consumed semi-solid foods with lower eating rates (g/s) than Dutch, Caucasian consumers by reducing bite size (g) and increasing consumption time (s). Consumers with decreased mastication efficiency or mild swallowing problems showed similar oral processing behaviour than healthy consumers, probably because reduction in eating capability was limited in the group. This demonstrates that different consumer groups adapt eating rate (g/s) in different ways by modifying bite size (g), consumption time (s) or both. To conclude, age, gender and ethnicity influence oral processing behaviour of liquid, semi-solid and solid foods differently. Understanding differences in oral processing behaviour of specific consumer groups can assist in steering sensory perception, food choice and energy intake of specific consumer groups such as the elderly.

    Making the most of imperfect data: a critical evaluation of standard information collected in farm household surveys
    Fraval, Simon ; Hammond, James ; Wichern, Jannike ; Oosting, Simon J. ; Boer, Imke J.M. De; Teufel, Nils ; Lannerstad, Mats ; Waha, Katharina ; Pagella, Tim ; Rosenstock, Todd S. ; Giller, Ken E. ; Herrero, Mario ; Harris, David ; Wijk, Mark T. van - \ 2019
    Experimental Agriculture 55 (2019)2. - ISSN 0014-4797 - p. 230 - 250.
    Household surveys are one of the most commonly used tools for generating insight into rural communities. Despite their prevalence, few studies comprehensively evaluate the quality of data derived from farm household surveys. We critically evaluated a series of standard reported values and indicators that are captured in multiple farm household surveys, and then quantified their credibility, consistency and, thus, their reliability. Surprisingly, even variables which might be considered ‘easy to estimate’ had instances of non-credible observations. In addition, measurements of maize yields and land owned were found to be less reliable than other stationary variables. This lack of reliability has implications for monitoring food security status, poverty status and the land productivity of households. Despite this rather bleak picture, our analysis also shows that if the same farm households are followed over time, the sample sizes needed to detect substantial changes are in the order of hundreds of surveys, and not in the thousands. Our research highlights the value of targeted and systematised household surveys and the importance of ongoing efforts to improve data quality. Improvements must be based on the foundations of robust survey design, transparency of experimental design and effective training. The quality and usability of such data can be further enhanced by improving coordination between agencies, incorporating mixed modes of data collection and continuing systematic validation programmes.
    Towards a global model for wetlands ecosystem services
    Janse, Jan H. ; Dam, Anne A. van; Hes, Edwin M.A. ; Klein, Jeroen J.M. de; Finlayson, C.M. ; Janssen, Annette B.G. ; Wijk, Dianneke van; Mooij, Wolf M. ; Verhoeven, Jos T.A. - \ 2019
    Current Opinion in Environmental Sustainability 36 (2019). - ISSN 1877-3435 - p. 11 - 19.

    Wetlands play an important role in the provision of important ecosystem services like the provision of clean water to the world, adaptation to climate change, and support for biodiversity; although they are sometimes also associated with adverse climate effects. Wetlands are, however, currently grossly underrepresented in global environmental models. In this paper, we explore the required functionality of a generic model of the effects of climate and land-use changes on wetlands ecosystem services worldwide. We briefly review existing models to identify elements which can be combined to compile a generic wetland model. The proposed global wetland model should be integrated into and receive data from existing hydrology and climate models. Wetland delineation can be based on local hydrological and topographical conditions and verified with global wetland databases. We conclude that an integrated approach combining hydrology, biogeochemistry and vegetation for wetlands is not available yet, however, useful building blocks exist that can be combined.

    How to model algal blooms in any lake on earth
    Janssen, Annette B.G. ; Janse, Jan H. ; Beusen, Arthur H.W. ; Chang, Manqi ; Harrison, John A. ; Huttunen, Inese ; Kong, Xiangzhen ; Rost, Jasmijn ; Teurlincx, Sven ; Troost, Tineke A. ; Wijk, Dianneke van; Mooij, Wolf M. - \ 2019
    Current Opinion in Environmental Sustainability 36 (2019). - ISSN 1877-3435 - p. 1 - 10.

    Algal blooms increasingly threaten lake and reservoir water quality at the global scale, caused by ongoing climate change and nutrient loading. To anticipate these algal blooms, models to project future algal blooms worldwide are required. Here we present the state-of-the-art in algal projection modelling and explore the requirements of an ideal algal projection model. Based on this, we identify current challenges and opportunities for such model development. Since most building blocks are present, we foresee that algal projection models for any lake on earth can be developed in the near future. Finally, we think that algal bloom projection models at a global scale will provide a valuable contribution to global policymaking, in particular with respect to SDG 6 (clean water and sanitation).

    Modulation of sensory perception of cheese attributes intensity and texture liking via ortho- and retro-nasal odors
    Han, Pengfei ; Fark, Therese ; Wijk, Rene A. de; Roudnitzky, Natacha ; Iannilli, Emilia ; Seo, Han Seok ; Hummel, Thomas - \ 2019
    Food Quality and Preference 73 (2019). - ISSN 0950-3293 - p. 1 - 7.
    Cheese - Congruency - Cross-modal sensory enhancement - Orthonasal - Retronasal - Texture

    Cross-modal sensory integration plays a key role in food flavor perception and acceptance during consumption. The current study investigated the effect of a butter odor, delivered at various stages of the oral processing cycle, on modulating the sensory properties of cheese. Twenty healthy volunteers (aged between 25 and 29 years, 12 women) were measured for their detection thresholds for the butter odor. In the sensory evaluation sessions, participants chewed and swallowed three types of cheese (low-fat, 20% fat content, LF; a medium-fat, 30% fat content, MF; high-fat, 40% fat content, HF, served in 16 × 16 × 12 mm3 cubes) while the butter odor was presented ortho- and retronasally in two concentrations at various points of the oral processing cycle. After swallowing, participants rated on a visual analogue scale for the intensities of cheese creaminess, butter note, overall flavor, and the pleasantness for cheese texture. Enhancement of added butter odor on perceived sensory attributes differed as a function of the delivery routes and timings. Creaminess intensity increased significantly when butter odor presented retro-nasally at the start of chewing. Butter note was enhanced when the retro-nasal odor was added during chewing. The texture pleasantness was increased with ortho-nasal odor presentation. In addition, for the creaminess intensity and texture liking enhancement, the observed effects were more pronounced with butter odor presentation at the lower concentration. Taken together, these findings suggested the importance of temporal congruency for cross-modal sensory enhancement in food flavor perception. The findings help to better understand flavor perception during oral processing of solid food and add value for future development of foods with nutritional benefits.

    Modeling water quality in the Anthropocene: directions for the next-generation aquatic ecosystem models
    Mooij, W.M. ; Wijk, Dianneke van; Beusen, A.H.W. ; Brederveld, R.J. ; Chang, M. ; Cobben, Marleen M.P. ; DeAngelis, D.L. ; Downing, A.S. ; Janssen, A.B.G. ; Hengeveld, G.M. - \ 2019
    Current Opinion in Environmental Sustainability 36 (2019). - ISSN 1877-3435 - p. 85 - 95.
    Everything changes and nothing stands still” (Heraclitus). Here we review three major improvements to freshwater aquatic ecosystem models — and ecological models in general — as water quality scenario analysis tools towards a sustainable future. To tackle the rapid and deeply connected dynamics characteristic of the Anthropocene, we argue for the inclusion of eco-evolutionary, novel ecosystem and social-ecological dynamics. These dynamics arise from adaptive responses in organisms and ecosystems to global environmental change and act at different integration levels and different time scales. We provide reasons and means to incorporate each improvement into aquatic ecosystem models. Throughout this study we refer to Lake Victoria as a microcosm of the evolving novel social-ecological systems of the Anthropocene. The Lake Victoria case clearly shows how interlinked eco-evolutionary, novel ecosystem and social-ecological dynamics are, and demonstrates the need for transdisciplinary research approaches towards global sustainability.
    IgE Cross-Reactivity of Cashew Nut Allergens
    Bastiaan-Net, Shanna ; Reitsma, Marit ; Cordewener, Jan H.G. ; Valk, Johanna P.M. van der; America, Twan A.H.P. ; Dubois, Anthony E.J. ; Gerth van Wijk, Roy ; Savelkoul, Huub F.J. ; Jong, Nicolette W. de; Wichers, Harry J. - \ 2019
    International Archives of Allergy and Immunology 178 (2019)1. - ISSN 1018-2438 - p. 19 - 32.
    Allergenicity - Cashew nut - Food allergy - IgE cross-reactivity - Immunoblotting - Tree nut allergy

    Background: Allergic sensitisation towards cashew nut often happens without a clear history of eating cashew nut. IgE cross-reactivity between cashew and pistachio nut is well described; however, the ability of cashew nut-specific IgE to cross-react to common tree nut species and other Anacardiaceae, like mango, pink peppercorn, or sumac is largely unknown. Objectives: Cashew nut allergic individuals may cross-react to foods that are phylogenetically related to cashew. We aimed to determine IgE cross-sensitisation and cross-reactivity profiles in cashew nut-sensitised subjects, towards botanically related proteins of other Anacardiaceae family members and related tree nut species. Method: Sera from children with a suspected cashew nut allergy (n = 56) were assessed for IgE sensitisation to common tree nuts, mango, pink peppercorn, and sumac using dot blot technique. Allergen cross-reactivity patterns between Anacardiaceae species were subsequently examined by SDS-PAGE and immunoblot inhibition, and IgE-reactive allergens were identified by LC-MS/MS. Results: From the 56 subjects analysed, 36 were positive on dot blot for cashew nut (63%). Of these, 50% were mono-sensitised to cashew nuts, 19% were co-sensitised to Anacardiaceae species, and 31% were co-sensitised to tree nuts. Subjects co-sensitised to Anacardiaceae species displayed a different allergen recognition pattern than subjects sensitised to common tree nuts. In pink peppercorn, putative albumin- and legumin-type seed storage proteins were found to cross-react with serum of cashew nut-sensitised subjects in vitro. In addition, a putative luminal binding protein was identified, which, among others, may be involved in cross-reactivity between several Anacardiaceae species. Conclusions: Results demonstrate the in vitro presence of IgE cross-sensitisation in children towards multiple Anacardiaceae species. In this study, putative novel allergens were identified in cashew, pistachio, and pink peppercorn, which may pose factors that underlie the observed cross-sensitivity to these species. The clinical relevance of this widespread cross-sensitisation is unknown.

    Sensory analysis of characterising flavours : Evaluating tobacco product odours using an expert panel
    Krüsemann, Erna J.Z. ; Lasschuijt, Marlou P. ; Graaf, C. de; Wijk, René A. de; Punter, Pieter H. ; Tiel, Loes van; Cremers, Johannes W.J.M. ; Nobelen, Suzanne van de; Boesveldt, Sanne ; Talhout, Reinskje - \ 2019
    Tobacco Control 28 (2019). - ISSN 0964-4563 - p. 152 - 160.
    advertising and promotion - prevention - public policy

    Objectives: Tobacco flavours are an important regulatory concept in several jurisdictions, for example in the USA, Canada and Europe. The European Tobacco Products Directive 2014/40/EU prohibits cigarettes and roll-your-own tobacco having a characterising flavour. This directive defines characterising flavour as 'a clearly noticeable smell or taste other than one of tobacco [⋯]'. To distinguish between products with and without a characterising flavour, we trained an expert panel to identify characterising flavours by smelling. Methods: An expert panel (n=18) evaluated the smell of 20 tobacco products using self-defined odour attributes, following Quantitative Descriptive Analysis. The panel was trained during 14 attribute training, consensus training and performance monitoring sessions. Products were assessed during six test sessions. Principal component analysis, hierarchical clustering (four and six clusters) and Hotelling's T-tests (95% and 99% CIs) were used to determine differences and similarities between tobacco products based on odour attributes. Results: The final attribute list contained 13 odour descriptors. Panel performance was sufficient after 14 training sessions. Products marketed as unflavoured that formed a cluster were considered reference products. A four-cluster method distinguished cherry-flavoured, vanilla-flavoured and menthol-flavoured products from reference products. Six clusters subdivided reference products into tobacco leaves, roll-your-own and commercial products. Conclusions: An expert panel was successfully trained to assess characterising odours in cigarettes and roll-your-own tobacco. This method could be applied to other product types such as e-cigarettes. Regulatory decisions on the choice of reference products and significance level are needed which directly influences the products being assessed as having a characterising odour.

    Using household survey data to identify large-scale food security patterns across Uganda
    Wichern, Jannike ; Heerwaarden, Joost van; Bruin, Sytze de; Descheemaeker, Katrien ; Asten, Piet J.A. van; Giller, Ken E. ; Wijk, Mark T. van - \ 2018
    PLoS ONE 13 (2018)12. - ISSN 1932-6203 - 23 p.
    To target food security interventions for smallholder households, decision makers need large-scale information, such as maps on poverty, food security and key livelihood activities. Such information is often based on expert knowledge or aggregated data, despite the fact that food security and poverty are driven largely by processes at the household level. At present, it is unclear if and how household level information can contribute to the spatial prediction of such welfare indicators or to what extent local variability is ignored by current mapping efforts. A combination of geo-referenced household level information with spatially continuous information is an underused approach to quantify local and large-scale variation, while it can provide a direct estimate of the variability of welfare indicators at the most relevant scale. We applied a stepwise regression kriging procedure to translate point information to spatially explicit patterns and create country-wide predictions with associated uncertainty estimates for indicators on food availability and related livelihood activities using household survey data from Uganda. With few exceptions, predictions of the indicators were weak, highlighting the difficulty in capturing variability at larger scale. Household explanatory variables identified little additional variation compared to environmental explanatory variables alone. Spatial predictability was strongest for indicators whose distribution was determined by environmental gradients. In contrast, indicators of crops that were more ubiquitously present across agroecological zones showed large local variation, which often overruled large-scale patterns. Our procedure adds to existing approaches that often only show large-scale patterns by revealing that local variation in welfare is large. Interventions that aim to target the poor must recognise that diversity in livelihood activities for income generation within any given area often overrides the variability of livelihood activities between distant regions in the country.
    Role for Arabidopsis PLC7 in Stomatal Movement, Seed Mucilage Attachment, and Leaf Serration
    Wijk, Ringo van; Zhang, Qianqian ; Zarza, Xavier ; Lamers, M. ; Reyes Marquez, F.C. ; Guardia, Aisha ; Scuffi, Denise ; García-Mata, Carlos ; Ligterink, W. ; Haring, M.A. ; Laxalt, A.M. ; Munnik, Teun - \ 2018
    Frontiers in Plant Science 9 (2018). - ISSN 1664-462X
    Phospholipase C (PLC) has been suggested to play important roles in plant stress and development. To increase our understanding of PLC signaling in plants, we have started to analyze knock-out (KO), knock-down (KD) and overexpression mutants of Arabidopsis thaliana, which contains nine PLCs. Earlier, we characterized PLC2, PLC3 and PLC5. Here, the role of PLC7 is functionally addressed. Promoter-GUS analyses revealed that PLC7 is specifically expressed in the phloem of roots, leaves and flowers, and is also present in trichomes and hydathodes. Two T-DNA insertion mutants were obtained, i.e., plc7-3 being a KO- and plc7-4 a KD line. In contrast to earlier characterized phloem-expressed PLC mutants, i.e., plc3 and plc5, no defects in primary- or lateral root development were found for plc7 mutants. Like plc3 mutants, they were less sensitive to ABA during stomatal closure. Double-knockout plc3 plc7 lines were lethal, but plc5 plc7 (plc5/7) double mutants were viable, and revealed several new phenotypes, not observed earlier in the single mutants. These include a defect in seed mucilage, enhanced leaf serration, and an increased tolerance to drought. Overexpression of PLC7 enhanced drought tolerance too, similar to what was earlier found for PLC3-and PLC5 overexpression. In vivo 32Pi-labeling of seedlings and treatment with sorbitol to mimic drought stress, revealed stronger PIP2 responses in both drought-tolerant plc5/7 and PLC7-OE mutants. Together, these results show novel functions for PLC in plant stress and development. Potential molecular mechanisms are discussed.
    An exploration of the three-layer model including stakeholders, markets and technologies for assessments of residential smart grids
    Reinders, Angèle ; übermasser, Stefan ; Sark, Wilfried van; Gercek, Cihan ; Schram, Wouter ; Obinna, Uchechi ; Lehfuss, Felix ; Mierlo, Barbara van; Robledo, Carla ; Wijk, Ad van - \ 2018
    Applied Sciences 8 (2018)12. - ISSN 2076-3417
    Electricity market - End-users - Energy products and services - Flexibility - Renewable energy - Smart grids - Stakeholders

    In this paper, a framework is presented for the evaluation of smart grid environment which is called the three-layer model. This three-layer model comprises three specific categories, or 'layers', namely, the stakeholder, market and technologies layers. Each layer is defined and explored herein, using an extensive literature study regarding their key elements, their descriptions and an overview of the findings from the literature. The assumption behind this study is that a solid understanding of each of the three layers and their interrelations will help in more effective assessment of residential smart grid pilots in order to better design products and services and deploy smart grid technologies in networks. Based on our review, we conclude that, in many studies, social factors associated with smart grid pilots, such as markets, social acceptance, and end-user and stakeholder demands, are most commonly defined as uncertainties and are therefore considered separately from the technical aspects of smart grids. As such, it is recommended that, in future assessments, the stakeholder and market layers should be combined with the technologies layer so as to enhance interaction between these three layers, and to be able to better evaluate residential smart energy systems in a multidisciplinary context.

    Managing Nutrients for Climatic Resilience in African Smallholder Maize Production
    Rurinda, Jairos ; Wijk, Mark Van; Mapfumo, Paul ; Giller, Ken - \ 2018
    Better crops with plant food 102 (2018)1. - ISSN 0006-0089 - p. 29 - 32.
    This paper presents the results of field studies conducted in Zimbabwe to quantify the yield response of maize to current and projected climatic conditions. The effect of management practices, such as cultivar choice, planting date and fertilizer use, were evaluated. The long-term impact of these management options was assessed through crop simulation modelling. It was shown that NPK fertilizer and manure use increased maize yield under both current and projected changes in climatic conditions in the area. The yield benefits of nutrient management were further increased when maize was planted within 3 weeks of the start of the wet season.
    Zorg-sport initiatieven in de wijk
    Mulderij, Lisanne - \ 2018
    Samenwerking met partners in de wijk en gemeente, verzekeraars
    Wagemakers, Annemarie - \ 2018
    Trade-offs in livestock development at farm level: Different actors with different objectives
    Salmon, Gareth ; Teufel, Nils ; Baltenweck, Isabelle ; Wijk, M. van; Claessens, L.F.G. ; Marshall, Karen - \ 2018
    Global Food Security 17 (2018). - ISSN 2211-9124 - p. 103 - 112.
    The livestock sector in Low and Middle Income Countries (LMICs) is evolving. In response to growing demand for livestock products, it is likely that smallholder production systems will experience varying forms of intensification. Associated decision making is made complex, not only with the intrinsic characteristics of livestock in LMICs (for instance as sources of income, assets, or social symbols), but also by diverse objectives of stakeholders and agricultural development paradigms. This paper discusses trade-offs that are likely to arise in the choice of livestock production systems; with a focus at household and farm level, economic gains, gender equity, environmental concerns, human nutrition and food safety are all considered. We begin by describing trajectories of livestock intensification in LMICs. Then potential trade-offs during such intensification are depicted; with examples concerning environmental, economic and social aspects. Recognising and understanding trade-offs is imperative; therefore we discuss decision making methods, the management of trade-offs and the balance between providing an average benefit for a population and the variation in benefit for individuals. Finally, a (partial) trade-off analysis is illustrated by use of a case study on household dairy cattle enterprises in Senegal. The discussion advocates for holistic approaches to agricultural development efforts, which include recognition of the multiple objectives and the associated trade-offs.
    Brechas de rendimeinto en el cultivo de palma de aceite: una revision cuantitativa de factores determinantes
    Woittiez, L.S. ; Wijk, Mark T. van; Slingerland, M.A. ; Noordwijk, M. van; Giller, K.E. - \ 2018
    Revista Palmas 39 (2018)1. - p. 16 - 68.
    Arabidopsis phospholipase C3 is involved in lateral root initiation and ABA responses in seed germination and stomatal closure
    Zhang, Qianqian ; Wijk, Ringo van; Shahbaz, Muhammad ; Roels, Wendy ; Schooten, Bas Van; Vermeer, Joop E.M. ; Zarza, Xavier ; Guardia, Aisha ; Scuffi, Denise ; García-Mata, Carlos ; Laha, Debabrata ; Williams, Phoebe ; Willems, Leo A.J. ; Ligterink, Wilco ; Hoffmann-Benning, Susanne ; Gillaspy, Glenda ; Schaaf, Gabriel ; Haring, Michel A. ; Laxalt, Ana M. ; Munnik, Teun - \ 2018
    Plant and Cell Physiology 59 (2018)3. - ISSN 0032-0781 - p. 469 - 486.
    ABA - Arabidopsis - Drought tolerance - Lateral root formation - Seed germination - Stomatal closure

    Phospholipase C (PLC) is well known for its role in animal signaling, where it generates the second messengers, inositol 1,4,5-trisphosphate (IP3) and diacylglycerol (DAG), by hydrolyzing the minor phospholipid, phosphatidylinositol 4,5-bisphosphate (PIP2), upon receptor stimulation. In plants, PLC's role is still unclear, especially because the primary targets of both second messengers are lacking, i.e. the ligand-gated Ca2+ channel and protein kinase C, and because PIP2 levels are extremely low. Nonetheless, the Arabidopsis genome encodes nine PLCs. We used a reversed-genetic approach to explore PLC's function in Arabidopsis, and report here that PLC3 is required for proper root development, seed germination and stomatal opening. Two independent knock-down mutants, plc3-2 and plc3-3, were found to exhibit reduced lateral root densities by 10-20%. Mutant seeds germinated more slowly but were less sensitive to ABA to prevent germination. Guard cells of plc3 were also compromised in ABA-dependent stomatal closure. Promoter-b-glucuronidase (GUS) analyses confirmed PLC3 expression in guard cells and germinating seeds, and revealed that the majority is expressed in vascular tissue, most probably phloem companion cells, in roots, leaves and flowers. In vivo 32Pi labeling revealed that ABA stimulated the formation of PIP2 in germinating seeds and guard cell-enriched leaf peels, which was significantly reduced in plc3 mutants. Overexpression of PLC3 had no effect on root system architecture or seed germination, but increased the plant's tolerance to drought. Our results provide genetic evidence for PLC's involvement in plant development and ABA signaling, and confirm earlier observations that overexpression increases drought tolerance. Potential molecular mechanisms for the above observations are discussed.

    Akkervogelvriendelijk bouwplan met zomergraan en overwinterende stoppels : Eindrapportage
    Geerts, R.H.E.M. ; Korevaar, H. ; Koole, B. ; Wijk, G.C.A. - \ 2018
    Wageningen UR, Wageningen Universiteit (Rapport WPR ) - 90 p.
    Agricultural diversification as an important strategy for achieving food security in Africa
    Waha, Katharina ; Wijk, Mark T. Van; Fritz, Steffen ; See, Linda ; Thornton, Philip K. ; Wichern, Jannike ; Herrero, Mario - \ 2018
    Global Change Biology 24 (2018)8. - ISSN 1354-1013 - p. 3390 - 3400.
    Farmers in Africa have long adapted to climatic and other risks by diversifying their farming activities. Using a multi‐scale approach, we explore the relationship between farming diversity and food security and the diversification potential of African agriculture and its limits on the household and continental scale. On the household scale, we use agricultural surveys from more than 28,000 households located in 18 African countries. In a next step, we use the relationship between rainfall, rainfall variability, and farming diversity to determine the available diversification options for farmers on the continental scale. On the household scale, we show that households with greater farming diversity are more successful in meeting their consumption needs, but only up to a certain level of diversity per ha cropland and more often if food can be purchased from off‐farm income or income from farm sales. More diverse farming systems can contribute to household food security; however, the relationship is influenced by other factors, for example, the market orientation of a household, livestock ownership, nonagricultural employment opportunities, and available land resources. On the continental scale, the greatest opportunities for diversification of food crops, cash crops, and livestock are located in areas with 500–1,000 mm annual rainfall and 17%–22% rainfall variability. Forty‐three percent of the African cropland lacks these opportunities at present which may hamper the ability of agricultural systems to respond to climate change. While sustainable intensification practices that increase yields have received most attention to date, our study suggests that a shift in the research and policy paradigm toward agricultural diversification options may be necessary.
    Origin and Processing Methods Slightly Affect Allergenic Characteristics of Cashew Nuts (Anacardium occidentale)
    Reitsma, Marit ; Bastiaan-Net, Shanna ; Sijbrandij, Lutske ; Weert, Evelien de; Sforza, Stefano ; Gerth van Wijk, Roy ; Savelkoul, Huub F.J. ; Jong, Nicolette W. de; Wichers, Harry J. - \ 2018
    Journal of Food Science 83 (2018)4. - ISSN 0022-1147 - p. 1153 - 1164.
    2D electrophoresis - Anacardium occidentale - cashew - in vitro gastric digestion
    The protein content and allergen composition was studied of cashews from 8 different origins (Benin, Brazil, Ghana, India, Ivory Coast, Mozambique, Tanzania, Vietnam), subjected to different in-shell heat treatments (steamed, fried, drum-roasted). On 2D electrophoresis, 9 isoforms of Ana o 1, 29 isoforms of Ana o 2 (11 of the acidic subunit, 18 of the basic subunit), and 8 isoforms of the large subunit of Ana o 3 were tentatively identified. Based on 1D and 2D electrophoresis, no difference in allergen content (Ana o 1, 2, 3) was detected between the cashews of different origins (P > 0.5), some small but significant differences were detected in allergen solubility between differently heated cashews. No major differences in N- and C-terminal microheterogeneity of Ana o 3 were detected between cashews of different origins. Between the different heat treatments, no difference was detected in glycation, pepsin digestibility, or IgE binding of the cashew proteins.
    Aroma effects on food choice task behavior and brain responses to bakery food product cues
    Wijk, Rene A. de; Smeets, Paul A.M. ; Polet, Ilse A. ; Holthuysen, Nancy T.E. ; Zoon, Jet ; Vingerhoeds, Monique H. - \ 2018
    Food Quality and Preference 68 (2018). - ISSN 0950-3293 - p. 304 - 314.
    Aroma - Bakery products - Food choice behavior - Functional magnetic resonance imaging - Reward
    Bread, and especially whole grain bread is an important source of dietary fibers. It was tested with behavioral and fMRI measures whether bread becomes more attractive when it is presented with bread aroma. Twenty-eight healthy normal-weight women were exposed to images of bakery products (brown bread, white bread and cookies) without aroma or with a congruent (bread aroma) or non-congruent (“warm wood”) aroma. In general, product effects were larger than aroma effects. Images of brown bread were preferred over images of white bread as shown by direct comparisons, choice reaction times, as well as liking and wanting scores. Aroma had no effect on liking and wanting, but did affect food choice task behavior, where images of brown bread were preferred more often in the presence of warm wood aroma and images of cookies were preferred more often in the presence of bread aroma. The fMRI data suggest that bread aroma may increase the salience of bakery products compared to no aroma and a non-food aroma. Specifically, bread aroma induced greater activation for cookies in areas related to reward anticipation. The correlations between behavioral measures and brain responses suggest lower attention for and a habitual response to brown bread and higher attention and a more goal-directed response to white bread. In conclusion, aroma can affect choice task behavior for brown and white bread albeit in an incongruent manner. The more habitual response to brown compared with white bread suggested by the neural data underscores that nudging towards brown bread consumption with (bread) aroma will probably not be effective.
    Can food choice be influenced by priming with food odours?
    Polet, I.A. ; Vingerhoeds, M.H. ; Perez-Cueto, F.J.A. ; Wijk, R.A. de - \ 2018
    Food Quality and Preference 66 (2018). - ISSN 0950-3293 - p. 148 - 152.
    Food choice - Odour - Priming - Real life
    Recent research suggests that non-attentively perceived odours may significantly influence people's food choices. This study's aim was to examine the effects of different types of non-attentively perceived food odours, namely, bread odour and cucumber odour, on subsequent lunch choices in a real-life setting. The study was conducted using a within-participant design (n = 37, age 21–55 years). Participants took part in three sessions: two priming conditions (bread and cucumber odour) and one control condition (no odour). During each session, participants started by answering a questionnaire for20 min, in a room in which they were exposed to one of the odour conditions. The questionnaire functioned as a ‘lure’ task. Subsequently, participants were guided to the restaurant where they could choose lunch from a buffet. Besides lunch choice, sociodemographic factors, personality traits, and eating behaviour factors were assessed. Odour priming and control conditions did not affect lunch selections (χ 2 (2, N = 37) = 28.1, p = 0.46). Self-reported positive mood was significantly affected by odour condition (F (2, 72) = 3.26, p = 0.044). In conclusion, odour condition did affect mood but not lunch choice. It is therefore questionable whether an odour prime can be used as a nudge to contribute to healthy food choice behaviour.
    Potenties voor herstel getijdenatuur in het Haringvliet, Hollands Diep en de Biesbosch
    Wijsman, Jeroen ; Escaravage, Vincent ; Huismans, Ymkje ; Nolte, Arno ; Wijk, Remi van der; Wang, Zheng Bing ; Ysebaert, Tom - \ 2018
    Yerseke : Wageningen Marine Research (Wageningen Marine Research rapport C008/18) - 110
    In verband met de verwachte positieve effecten op de natuur, met name het herstel van vismigratie, gaan vanaf 2018 de Haringvlietsluizen op een kier. Als gevolg van deze aanpassing kan er tijdens vloed zoutwater binnendringen in het westelijk deel van het Haringvliet. Het verder openzetten van de Haringvlietsluizen dan alleen op een kier, biedt ook de mogelijkheid voor meer getijdynamiek in het Haringvliet, maar ook verder landinwaarts, het Hollands Diep en de Biesbosch, waardoor er meer intergetijdengebied ontstaat. In deze studie is een verkenning gedaan naar de mogelijkheden van het herstel van getijdenatuur in het Haringvliet, Hollands Diep en de Biesbosch. In deze studie zijn vijf varianten doorgerekend: (1) Huidig beheer, (2) Kierbesluit, (3) 80 cm getij, (4) Stormvloedkering en (5) Klimaatscenario (met stormvloedkering).
    The effect of a default-based nudge on the choice of whole wheat bread
    Kleef, Ellen van; Seijdell, Karen ; Vingerhoeds, Monique H. ; Wijk, René A. de; Trijp, Hans C.M. van - \ 2018
    Appetite 121 (2018). - ISSN 0195-6663 - p. 179 - 185.
    Behavioural economics - Default effect - Food choice behaviour - Intervention - Nudging - Whole wheat bread
    Consumer choices are often influenced by the default option presented. This study examines the effect of whole wheat bread as a default option in a sandwich choice situation. Whole wheat bread consists of 100% whole grain and is healthier than other bread types that are commonly consumed, such as brown or white bread. A pilot survey (N = 291) examined the strength of combinations of toppings and bread type as carrier to select stimuli for the main study. In the main experimental study consisting of a two (bread type) by two (topping type) between-subjects design, participants (N = 226) were given a free sandwich at a university stand with either a relatively unhealthy deep-fried snack (croquette) or a healthy topping. About half of the participants were offered a whole wheat bun unless they asked for white bun, and the other half were offered a white bun unless they asked for a whole wheat bun. Regardless of the topping, the results show that when the whole wheat bun was the default option, 108 out of 115 participants (94%) decided to stick with this default option. When the default of bread offered was white, 89 out of 111 participants (80%) similarly chose to stick with this default. Across conditions, participants felt equally free to make a choice. The attractiveness of and willingness to pay for the sandwich were not affected by default type of bread. This study demonstrated a strong default effect of bread type. This clearly shows the benefit of steering consumers towards a healthier bread choice, by offering healthier default bread at various locations such as restaurants, schools and work place canteens.
    Small percentage of anaphylactic reactions treated with epinephrine during food challenges in Dutch children
    Valk, Johanna P.M. van der; Berends, Irene ; Wijk, Roy Gerth van; Arends, Nicolette J.T. ; Maaren, Maurits S. van; Groot, Hans de; Wichers, Harry J. ; Emons, Joyce A.M. ; Dubois, Anthony E.J. ; Jong, Nicolette W. de - \ 2018
    Annals of Allergy, Asthma and Immunology 120 (2018)3. - ISSN 1081-1206 - p. 300 - 303.
    Background: Severe allergic reactions, including anaphylaxis, occur during oral food challenges (OFCs) and the first-line treatment of anaphylaxis is epinephrine. Objective: To evaluate the percentage of anaphylactic reactions treated with epinephrine during OFCs and to identify associated factors for the administration of epinephrine. Methods: Children who underwent an OFC with peanut, hazelnut, cow's milk, hen's egg, or cashew nut from 2005 through 2015 in the Netherlands were evaluated. Children with reactions meeting the criteria for anaphylaxis according to the European Academy of Allergy and Clinical Immunology guidelines for food allergy and anaphylaxis were included. Children with an anaphylactic reaction treated with vs without epinephrine were compared. Possible factors associated with the administration of epinephrine, such as age, sex, symptoms consistent with asthma, history of an allergic reaction to the tested allergen, and symptom types during the anaphylactic reaction, were evaluated using logistic regression analysis. Results: Eighty-three children in clinical and research settings (43% boys; median age, 7 years; range, 1-17) who met the criteria for anaphylaxis were included in this study. Thirty-two of 83 children (39%) with anaphylaxis were treated with epinephrine. Respiratory symptoms during the OFC were treated significantly more often with epinephrine than gastrointestinal symptoms (P = .01). Conclusion: Only 39% of children with anaphylaxis, according to the guideline criteria, were treated with epinephrine during the OFC and most of these children had respiratory symptoms. There is need for an easy-to-use international guideline for the treatment of allergic symptoms during OFCs.
    Supermarket shopper movements versus sales and the effects of scent, light, and sound
    Wijk, René A. de; Maaskant, Anna M. ; Kremer, Stefanie ; Holthuysen, Nancy T.E. ; Stijnen, Daniella A.J.M. - \ 2018
    Food Quality and Preference 70 (2018). - ISSN 0950-3293 - p. 32 - 39.
    Light - Scent - Shopper movements/sales - Sound - Supermarket

    Common sense assumes that supermarket sales of specific products are driven by the number of visitors and by their behavior during their visit. In addition, certain shopping ambiances probably stimulate a certain shopper behavior, resulting in more sales. Surprisingly, these relationships have rarely been experimentally tested in real-life supermarkets. Number of shoppers, shopper movement patterns, and sales of selections of white wines, coffees, and fruits in a medium-size supermarket were monitored over an 18-week period. Wines were visited for longer (9.5. s) than coffees (4.4. s) and fruits (4.5. s), but visitors to wines were relatively stationary and visits resulted less often in a sale (1 sale per 41.2 visits) than visits to coffees (1 sale per 21.7 visits) and fruits (1 sale per 3.7 visits). Visit frequency correlated positively with higher sales for coffee (Beta = 0.64, p <. 0.001) and for fruit (Beta = 0.33, p = 0.02) but not for wine. Wine, fruit, and coffee sales increased with the number of directional changes during a visit (p <. 0.001). Sales correlated positively with visit duration only for wine (Beta = 0.74, p <. 0.001). Local variations in scent, sound, and light conditions did not affect visit frequency or sales, but did affect speed during coffee (p = 0.04) and wine (p = 0.03) visits.

    Agricultural intensification scenarios, household food availability and greenhouse gas emissions in Rwanda : Ex-ante impacts and trade-offs
    Paul, B.K. ; Frelat, R. ; Birnholz, C. ; Ebong, C. ; Gahigi, A. ; Groot, J.C.J. ; Herrero, M. ; Kagabo, D.M. ; Notenbaert, A. ; Vanlauwe, B. ; Wijk, M.T. van - \ 2018
    Agricultural Systems 163 (2018). - ISSN 0308-521X - p. 16 - 26.
    Climate smart agriculture - Ex-ante impact assessment - Household modeling - Low carbon development - Sub-Saharan Africa - Sustainable intensification
    Rwanda's agricultural sector is facing severe challenges of increasing environmental degradation, resulting in declining productivity. The problem is likely to be further aggravated by the growing population pressure. A viable pathway is climate smart agriculture, aiming at the triple win of improving food security and climate change adaptation, while contributing to mitigation if possible. The Government of Rwanda has initiated ambitious policies and programs aiming at low emission agricultural development. Crop focused policies include the Crop Intensification Program (CIP) which facilitates access to inorganic fertilizer and improved seeds. In the livestock subsector, zero-grazing and improved livestock feeding are encouraged, and the Girinka program provides poor farm households with a crossbred dairy cow. In this study, we aimed at assessing the potential impact of these policy programs on food availability and greenhouse gas (GHG) emissions of 884 households across different agro-ecologies and farming systems in Rwanda. Household level calculations were used to assess the contribution of current crops, livestock and off-farm activities to food availability and GHG emissions. Across all sites, 46% of households were below the 2500kcalMAE-1 yr-1 line, with lower food availability in the Southern and Eastern Rwanda. Consumed and sold food crops were the mainstay of food availability, contributing between 81.2% (low FA class) to 53.1% (high FA class). Livestock and off-farm income were the most important pathways to higher FA. Baseline GHG emissions were low, ranging between 395 and 1506kg CO2e hh-1 yr-1 per site, and livestock related emissions from enteric fermentation (47.6-48.9%) and manure (26.7-31.8%) were the largest contributors to total GHG emissions across sites and FA classes. GHG emissions increased with FA, with 50% of the total GHG being emitted by 22% of the households with the highest FA scores. Scenario assessment of the three policy options showed strong differences in potential impacts: Girinka only reached one third of the household population, but acted highly pro-poor by decreasing the households below the 2500kcalMAE-1 yr-1 line from 46% to 35%. However, Girinka also increased GHG by 1174kg CO2e hh-1 yr-1, and can therefore not be considered climate-smart. Improved livestock feeding was the least equitable strategy, decreasing food insufficient households by only 3%. However, it increased median FA by 755kcalMAE-1 yr-1 at a small GHG increase (50kg CO2e hh-1 yr-1). Therefore, it is a promising option to reach the CSA triple win. Crop and soil improvement resulted in the smallest increase in median FA (FA by 755kcalMAE-1 yr-1), and decreasing the proportion of households below 2500kcalMAE-1 yr-1 by 6%. This came only at minimal increase in GHG emissions (23kg CO2e hh-1 yr-1). All policy programs had different potential impacts and trade-offs on different sections of the farm household population. Quick calculations like the ones presented in this study can assist in policy dialogue and stakeholder engagement to better select and prioritize policies and development programs, despite the complexity of its impacts and trade-offs.
    The Rural Household Multi-Indicator Survey (RHoMIS) for rapid characterisation of households to inform climate smart agriculture interventions: Description and applications in East Africa and Central America
    Hammond, James ; Fraval, Simon ; Etten, Jacob van; Suchini, Jose Gabriel ; Mercado, Leida ; Pagella, Tim ; Frelat, Romain ; Lannerstad, Mats ; Douxchamps, Sabine ; Teufel, Nils ; Valbuena, Diego ; Wijk, Mark T. van - \ 2017
    Agricultural Systems 151 (2017). - ISSN 0308-521X - p. 225 - 233.
    Farm household - Monitoring - Multiple indicators - Smallholder farming

    Achieving climate smart agriculture depends on understanding the links between farming and livelihood practices, other possible adaptation options, and the effects on farm performance, which is conceptualised by farmers as wider than yields. Reliable indicators of farm performance are needed in order to model these links, and to therefore be able to design interventions which meet the differing needs of specific user groups. However, the lack of standardization of performance indicators has led to a wide array of tools and ad-hoc indicators which limit our ability to compare across studies and to draw general conclusions on relationships and trade-offs whereby performance indicators are shaped by farm management and the wider social-environmental context. RHoMIS is a household survey tool designed to rapidly characterise a series of standardised indicators across the spectrum of agricultural production and market integration, nutrition, food security, poverty and GHG emissions. The survey tool takes 40–60 min to administer per household using a digital implementation platform. This is linked to a set of automated analysis procedures that enable immediate cross-site bench-marking and intra-site characterisation. We trialled the survey in two contrasting agro-ecosystems, in Lushoto district of Tanzania (n = 150) and in the Trifinio border region of Guatemala, El Salvador and Honduras (n = 285). The tool rapidly characterised variability between farming systems at landscape scales in both locations identifying key differences across the population of farm households that would be critical for targeting CSA interventions. Our results suggest that at both sites the climate smartness of different farm strategies is clearly determined by an interaction between the characteristics of the farm household and the farm strategy. In general strategies that enabled production intensification contributed more towards the goals of climate smart agriculture on smaller farms, whereas increased market orientation was more successful on larger farms. On small farms off-farm income needs to be in place before interventions can be promoted successfully, whereas on the larger farms a choice is made between investing labour in off-farm incomes, or investing that labour into the farm, resulting in a negative association between off-farm labour and intensification, market orientation and crop diversity on the larger farms, which is in complete opposition to the associations found for the smaller farms. The balance of indicators selected gave an adequate snap shot picture of the two sites, and allowed us to appraise the ‘CSA-ness’ of different existing farm strategies, within the context of other major development objectives.

    Groene initiatieven voor dagbesteding in de stad
    Hassink, J. ; Vaandrager, L. ; Bruin, S.R. de; Buist, Y. ; Lindhout, M. - \ 2017
    Voorzieningen voor dagbesteding sluiten niet altijd aan op de wensen en mogelijkheden van mensen met dementie. Dagbesteding op een zorgboerderij blijkt een voorziening die mensen met dementie en hun mantelzorgers vaak wel aanspreekt. Gezien deze positieve ervaringen is er interesse voor vergelijkbare plekken in steden. Dit gebeurt steeds vaker in de vorm van stadsboerderijen, buurttuinen die worden opgezet door wijkbewoners en zorginstellingen die hun tuin openstellen voor thuiswonende mensen met dementie in de buurt. Er is echter nog weinig bekend over deze initiatieven. Hoe zien deze groene initiatieven eruit? Wat betekenen ze voor mensen met dementie, hun mantelzorgers en de wijk? Wat zijn sterke en zwakke punten? Hoe zijn dergelijke initiatieven te financieren?
    Hydroponically grown leek : Slowly growing to maturity
    Os, E.A. van; Weel, P.A. van; Wilms, J.A.M. ; Bruins, M.A. ; Verhoeven, J. ; Wijk, K. van - \ 2017
    In: Proceedings of the ICESC2015. - International Society for Horticultural Science (Acta Horticulturae ) - ISBN 9789462611726 - p. 79 - 86.
    Deep flow technique - Floating panels - Nitrogen - Nitrogen efficiency - Water

    Leek traditionally grows in a sandy soil in the open field in The Netherlands. However, the vulnerability of sandy soils to leaching of nutrients to ground- and surface water is high. Therefore leek was chosen for experiments to be grown out of the soil in the open field. Investigations took place to certain aspects of system development which were reported in 2011. During the following years the research focused on commercializing the design (supporting tubes in floating panels in a DFT system), upscaling the system to several ponds of 200 m2, marketing the product, solving specific problems which appear during those experiments (oxygen content of the nutrient solution, continuous circulation, virus symptoms) and economic aspects. The semi-commercial system developed was based on various trials at which a plant density of more than 70 plants m-2 is needed to achieve plants of more than 200 g which are thicker than 2.0 cm. Hydroponically grown leek should be graded before planting on the panels. Fast growing cultivars should be chosen year round. Uniform planting material is needed for a uniform, single date, harvest. The age of the plant is of less importance for the quality of the harvested product. This gives flexibility in the planting date which often depends on the harvesting date of the former crop and, consequently the weather before. Besides the plants should be >20 g to be planted in the 20 cm long tubes, otherwise the growth is delayed (no catchment of light inside the tube). The cultivation period was similar to earlier trials (50-75 d). The taste of hydroponically grown leek was comparable with leeks raised in soil. During cultivation, symptoms of the yellow stripe virus were seen more frequent compared to soil grown leek. Reuse of the nutrient solution during 4 crops a year saves about 50% of the fertilizers required. Another aspect of importance in The Netherlands is the surplus of rainfall (800 mm average year-1) during the growing season compared to the water uptake (300-500 mm). Adaptation of the system or discharge strategy was investigated Hydroponically grown leek slowly grows to a mature cultivation system by solving the topics mentioned-above, therefor it can be used by commercial growers now. The importance of a slow upscale was proven by the appearance of several unforeseen aspects (oxygen, rainfall, duration of irrigation), while in marketing a first step is taken to bring hydroponically grown leek as a distinguishable product.

    Food availability and livelihood strategies among rural households across Uganda
    Wichern, Jannike ; Wijk, Mark T. van; Descheemaeker, Katrien ; Frelat, Romain ; Asten, Piet J.A. van; Giller, Ken E. - \ 2017
    Food Security 9 (2017)6. - ISSN 1876-4517 - p. 1385 - 1403.
    Crop choice - District - East Africa - Food security - Household level - Smallholder farms
    Despite continuing economic growth, Uganda faces persistent challenges to achieve food security. The effectiveness of policy and development strategies to help rural households achieve food security must improve. We present a novel approach to relate spatial patterns of food security to livelihood strategies, including the contribution of on- and off-farm activities to household food availability. Data from 1927 households from the World Bank Living Standards Measurement Study were used to estimate the calorific contribution of livelihood activities to food availability. Consumption of crops produced on-farm contributed most to food availability for households with limited food availability, yet the majority of these households were not food self-sufficient. Off-farm and market-oriented on-farm activities were more important for households with greater food availability. Overall, off-farm income was important in the north, while market-oriented on-farm activities were important in western and central Uganda. Food availability patterns largely matched patterns of agroecological conditions and market access, with households doing worst in Uganda’s drier and remote northeast. Less food-secure households depended more on short-cycle food crops as compared with better-off households, who focused more on plantation (cash) crops, although this varied among regions. Targeting interventions to improve food security should consider such differences in enterprise choice and include options to improve household market access and off-farm income opportunities.
    Bringing food availability to scale : Mapping livelihood strategies for household food availability across Uganda
    Wichern, J. ; Wijk, M.T. van; Heerwaarden, J. van; Bruin, S. de; Descheemaeker, K.K.E. ; Asten, P.J.A. van; Giller, K.E. - \ 2017
    - 2 p.
    De kracht van sport in de wijk voor: Kwetsbare jongeren
    Goor, Roel van; Super, Sabina ; Holman, Marije - \ 2017
    In: Kracht van Sport in de Wijk / Vervoorn, Cees, Deutekom, Marije, Dekkers, Vera, - p. 29 - 46.
    Lezingenreeks 2017: Kracht van Sport in de Wijk

    Biedt sport kwetsbare jongeren meer structuur in hun dagelijkse leven? Voelt een vluchteling zich eerder welkom door sportdeelname? Leert sport mensen met psychiatrische problemen beter om te gaan met tegenslag? In de vijfdelige lezingreeks ‘Kracht van Sport’ stond in 2017 de problematiek en inzet van sport bij diverse doelgroepen in de wijk centraal.

    In de lezingenreeks Kracht van Sport in de Wijk gingen experts op zoek naar manieren waarop welzijnswerkers, zorgverleners en professionals sport gezamenlijk als middel kunnen inzetten om de leefkwaliteit van wijkbewoners te verhogen.
    De kracht van sport in de wijk voor: Mensen met een beperking
    Kampen, Thomas ; Leenaars, Karlijn ; Weidemann, Kim - \ 2017
    In: Kracht van Sport in de Wijk / Vervoorn, Cees, Deutekom, Marije, Dekkers, Vera, - p. 13 - 28.
    Lezingenreeks 2017: Kracht van Sport in de Wijk

    Biedt sport kwetsbare jongeren meer structuur in hun dagelijkse leven? Voelt een vluchteling zich eerder welkom door sportdeelname? Leert sport mensen met psychiatrische problemen beter om te gaan met tegenslag? In de vijfdelige lezingreeks ‘Kracht van Sport’ stond in 2017 de problematiek en inzet van sport bij diverse doelgroepen in de wijk centraal.

    In de lezingenreeks Kracht van Sport in de Wijk gingen experts op zoek naar manieren waarop welzijnswerkers, zorgverleners en professionals sport gezamenlijk als middel kunnen inzetten om de leefkwaliteit van wijkbewoners te verhogen.
    Rapid Buffer and Ligand Screening for Affinity Chromatography by Multiplexed Surface Plasmon Resonance Imaging
    Geuijen, K.P.M. ; Wijk-Basten, Danielle E.J.W. van; Egging, Davis F. ; Schasfoort, Richard B.M. ; Eppink, M.H.M. - \ 2017
    Biotechnology Journal 12 (2017). - ISSN 1860-6768 - 9 p.
    Protein purifications are often based on the principle of affinity chromatography, where the protein of interest selectively binds to an immobilized ligand. The development of affinity purification requires selecting proper wash and elution conditions. In recent years, miniaturization of the purification process is applied to speed up the development (e.g., microtiterplates, robocolumns). The application of surface plasmon resonance imaging (SPRi) as a tool to simultaneously screen many buffer conditions for wash and elution steps in an affinity-based purification process is studied. Additionally, the protein A ligand stability after exposure to harsh cleaning conditions often limits the reuse of resins and is determined at lab scale. The SPRi technology to screen ligand life-time with respect to alkali stability is used. It is also demonstrated that SPRi can successfully be applied in screening experiments for process developments in a miniaturized approach. The amount of resin, protein and buffer in these studies is reduced 30–300-fold compared to 1 mL column scale, and approximately 10–1000-fold compared to filter plate experiments. The overall development time can be decreased from several months towards days. The multiplexed SPRi can be applied in screening affinity chromatography conditions in early stage development for ligand development and recombinant protein production
    Kick-off bijeenkomst project 'Zorg-sport initiatieven in de wijk: onderzoek naar participatie, actie-elementen, impact en financieringsmodellen.
    Mulderij, Lisanne - \ 2017
    Zorg-sport initiatieven in de wijk
    Communiceren van statistische informatie over onzekerheid in het tactisch-strategische waterkwantiteitsbeheer
    Knotters, Martin ; Poortvliet, P.M. ; Verstoep, Joël ; Wijk, Jiska van; Bergsma, Petra - \ 2017
    Amersfoort : Stowa (Stowa rapport 2017-21) - ISBN 9789057737459 - 41
    Om doelmatige beslissingen te kunnen nemen hebben waterschappen voortdurend informatie nodig over de toestand van het watersysteem in hun beheergebied. Hiervoor wordt gemonitord, onderzoek gedaan, worden (model)berekeningen gemaakt en worden op basis daarvan adviezen voor investeringen voorgelegd aan het bestuur. De basis van deze adviezen is veelal geen hard cijfer, maar een getal dat omgeven is met inschattingen en onzekerheden. Zo bestaat dé opgave voor wateroverlast in de vorm van een hard getal in kuubs of hectares niet, maar is dit een inschatting met een bepaalde onzekerheid, zeker als om lange tijdsperioden tot 2050 gaat. In deze studie is onderzocht hoe over onzekerheden gecommuniceerd wordt richting bestuurders, met als casus de wateropgave voor wateroverlast.
    Understanding heterogeneity in decision-making among elderly consumers: the case of functional foods
    Zanden, Lotte D.T. van der - \ 2017
    Wageningen University. Promotor(en): J.C.M. van Trijp, co-promotor(en): P.W. Kleef; R.A. de Wijk. - Wageningen : Wageningen University - ISBN 9789463431439 - 161
    voedselopname - ouderen - voedselsamenstellingtabellen - voedselverrijking - ouderenvoeding - leeftijdsgroepen - marketing - marketing van voedingsmiddelen - ziekenhuisdiëten - besluitvorming - consumenten - voedselconsumptie - food intake - elderly - food composition tables - food enrichment - elderly nutrition - age groups - marketing - food marketing - hospital diets - decision making - consumers - food consumption

    The population of elderly has grown considerably over the past few decades, due to reduced birth rates and increased life expectancy. Old age is, however, still associated with a higher incidence of various health conditions that pose a threat to quality of life and result in high healthcare costs. Various products and services could help elderly to stay active and healthy for longer if they were adopted, such as mobility aids, home modifications and functional foods. A key challenge is to position products and services like these on the market in such a way that elderly can see their value and will start using them. In doing this, it is crucial to know what elderly need and to understand how they make decisions. This thesis therefore aims to provide a deeper understanding of decision-making among elderly consumers. It does so using functional foods as an example, and concentrates on answering the following research questions: 1) Which types of wants, inferences and intentions characterize the elderly consumer population? 2) What are relevant ways to distinguish between elderly consumers? and 3) How can elderly consumers be motivated to form consumption intentions for products and services aimed at promoting their wellbeing?

    An experience-sampling paradigm shows that there are age-related differences in both desires (i.e. wants), such as the desire for food, and goals, such as the goal to work (i.e. intentions), but not in the way these wants and intentions interact with each other (Chapter 2). Young and old consumers experience the same types of conflict between their wants and intentions. The extent of conflict does change with age however, such that older adults experience conflict less often and less strongly than younger adults. This age-related difference can be partly explained by the way in which consumers perceive the time they have left in their lives. Those who perceive time as limited, experience more conflict. Zooming in on product-specific decision-making, a series of focus groups indicates that elderly consumers overall want to use healthy products that they use frequently as a basis for enrichment with protein (Chapter 3). Most elderly do not display intentions to purchase and use such products, however, either because they do not feel the need to use functional foods or because they hold various negative inferences regarding functional foods, such as a high price or bad taste. Importantly, elderly consumers differ strongly in their wants, inferences and intentions, suggesting that segmentation of this population is warranted.

    A narrative review reveals that there are various ways to segment the elderly consumer population, for example based on age, future time perspective or purchase behaviour, and every approach has its strengths and weaknesses (Chapter 4). Based on the objectives of a segmentation approach one can, however, make an informed decision regarding which segmentation base to use. In the functional food market, elderly consumers may best be segmented using a segmentation base on the food or product level (i.e. rather than the person level) that results in segments in which consumers have similar needs and wants, for example the attributes benefits that consumers seek. A segmentation study shows that using such a segmentation base results in segments that provide concrete instructions for the development of functional foods (Chapter 5). The resulting segments of elderly have unique preferences that do not necessarily reflect those of the average elderly consumer and thereby provide useful insights that can help increase our understanding of elderly consumers.

    Segmentation also provides a basis for tailoring products to the needs and wants of elderly consumers. A segmentation study illustrates that such tailoring can increase elderly consumers’ willingness to try protein-enriched foods for the first time (i.e. trial purchase), as well as their willingness to use such products on a more regular basis (i.e. repeat purchase) (Chapter 5). For a small group of elderly, tailoring proves to be ineffective, however, as they categorically reject all types of protein-enriched foods presented to them. These elderly are relatively uninterested in the concept of functional foods, which may be due to negative inferences surrounding such products. Overcoming the activation of such negative inferences may be useful in motivating elderly consumers to use protein-enriched foods. A field study in a hospital setting shows that the implementation of a verbal prompt intervention that motivates consumers to make decisions without much can increase the consumption of protein (Chapter 6). By understanding and capitalizing on cognitive biases in human decision-making, interventions like these can motivate consumers to form consumption intentions even when they hold negative inferences about products or services.

    Overall, this thesis shows that although elderly consumers share an age bracket they are strongly heterogeneous in their wants, inferences and intentions. This heterogeneity is robust, as it can even be observed when zooming in on decision-making regarding a specific product category (i.e. protein-enriched foods). Our understanding of the elderly consumer population increases by studying this heterogeneity, as it provides insights beyond those that apply to the group of elderly that reflect the average. In studying heterogeneity, it pays off to focus on bases that are predictive of behaviour while demographic characteristics like age provide only few insights. Industry and health institutions can also benefit from an increased understanding of the composition of the elderly population and how they make decisions. Such understanding may provide them with concrete instructions for the development and commercialization of products and services for this growing group of consumers.

    Prediction of cashew nut allergy in sensitized children
    Valk, Johanna P.M. van der; Vergouwe, Yvonne ; Wijk, R.G. van; Steyerberg, Ewout W. ; Reitsma, Marit ; Wichers, Harry J. ; Savelkoul, Huub F.J. ; Vlieg-Boerstra, Berber ; Groot, Hans de; Dubois, Anthony E.J. ; Jong, Nicolette W. De - \ 2017
    Pediatric Allergy and Immunology 28 (2017)5. - ISSN 0905-6157 - p. 487 - 490.
    Kracht van sport - kwetsbare jongeren
    Super, Sabina - \ 2017
    Lezing binnen de reeks Kracht van Sport in de Wijk - InHolland Hogeschool
    Zintuigen prikkelen stimuleert verkoop niet
    Wijk, Rene de - \ 2017

    De geur van vers gebrande koffie, sfeervolle verlichting bij het wijnassortiment. Retailers prikkelen onze zintuigen om onze kooplust te stimuleren. Maar het werkt niet, blijkt uit Wageningse onderzoek.

    Habituation and adaptation to odors in humans
    Pellegrino, R. ; Sinding, C. ; Wijk, R.A. de; Hummel, T. - \ 2017
    Physiology and Behavior 177 (2017). - ISSN 0031-9384 - p. 13 - 19.
    Adaptation - Desensitization - Human - Neuroscience - Olfaction - Smell

    Habituation, or decreased behavioral response, to odors is created by repeated exposure and several detailed characteristics, whereas adaptation relates to the neural processes that constitute this decrease in a behavioral response. As with all senses, the olfactory system continually encounters an enormous variety of odorants which is why mechanisms must exist to segment them and respond to changes. Although most olfactory habitation studies have focused on animal models, this non-systematic review provides an overview of olfactory habituation and adaptation in humans, and techniques that have been used to measure them. Thus far, psychophysics in combination with modern techniques of neural measurement indicate that habituation to odors, or decrease of intensity, is relatively fast with adaptation occurring more quickly at higher cerebral processes than peripheral adaptation. Similarly, it has been demonstrated that many of the characteristics of habitation apply to human olfaction; yet, evidence for some characteristics such as potentiation of habituation or habituation of dishabituation need more support. Additionally, standard experimental designs should be used to minimize variance across studies, and more research is needed to define peripheral-cerebral feedback loops involved in decreased responsiveness to environmental stimuli.

    Governing Nature Tourism in Eastern and Southern Africa
    Duim, V.R. van der; Wijk, J.J. van; Lamers, M.A.J. - \ 2017
    In: Nature Tourism / Chen, J.S., Prebensen, Nina K., London/New York : Routledge, Taylor & Francis Group (Contemporary Geographies of Leisure, Tourism and Mobility ) - ISBN 9781138961739 - p. 146 - 158.
    Gezondheidsmakelaars verbeteren het Gezondheidsbevorderend Systeem van hun wijk of gemeente
    Fransen, G.A.J. ; Riet, A. v.d.; Ham, L.T.J. v.d.; Wagemakers, Annemarie ; Molleman, G.R.M. - \ 2017
    In: Nederlands Congres Volksgezondheid 2017 - De professional maakt het verschil. -
    Achtergrond en doelstelling:
    Sinds 2009 zijn er gezondheidsmakelaars werkzaam bij GGD Gelderland-Zuid, iedere gezondheidsmakelaar heeft zijn eigen wijken of gemeenten. Zij hebben als taak om het GezondheidsBevorderend Systeem (GBS) in hun gemeente/wijk te verbeteren, zoals beschreven in ons logisch model (gepresenteerd op NCVGZ 2015). Het doel van dit onderzoek is om een monitoringsinstrument te ontwikkelen voor het meten van het GBS en een eerste meting uit te voeren, zodat we inzicht krijgen in hoe “sterk” het GBS van iedere gemeente/wijk is.

    Methode:
    8 variabelen zijn benoemd om het GBS te operationaliseren: samenwerking; samenhang; duurzaamheid; integrale aanpak; draagvlak; aanpak gebaseerd op een gezondheidsprofiel; in staat zijn tussentijdse resultaten zichtbaar te maken; bereik einddoelgroep. Vanuit literatuurstudie is gezocht naar valide instrumenten om deze variabelen te meten en te kwantificeren en is een monitoringsinstrument ontwikkeld.
    Per gemeente/wijk zijn 8 stakeholders uitgenodigd om de vragenlijst in te vullen: de gezondheidsmakelaar, ambtenaar volksgezondheid, huisarts, wijkverpleegkundige, welzijn, sportservice, fysiotherapeut en adviseur gezonde school. De meting vindt nu plaats in het hele werkgebied van GGD Gelderland-Zuid (16 gemeenten waaronder Nijmegen (8 wijken) en Wijchen (2 wijken)). Naast de vragenlijst vindt er documentanalyse plaats en gesprekken met gezondheidsmakelaar en evt andere stakeholders om de resultaten goed te kunnen duiden en in de context te beoordelen.

    Resultaten:
    Per gemeente/wijk zal een factsheet gemaakt worden met daarop de scores per variabele (gemiddelde van de 8 stakeholders). De resultaten verwachten wij in februari 2017.

    Conclusie en aanbevelingen: Met dit monitoringsinstrument zijn we in staat om de sterke van het GBS te meten, waarmee de gezondheidsmakelaar beter kan bepalen waar het GBS van zijn/haar gemeente versterkt kan worden en hij/zij op zou kunnen inzetten. Daarnaast dragen deze metingen bij aan het zichtbaar maken van de resultaten van de gezondheidsmakelaars.
    Low percentage of clinically relevant pistachio nut and mango co-sensitisation in cashew nut sensitised children
    Valk, J.P.M. van der; Bouche, R. el; Gerth van Wijk, R. ; Groot, H. de; Wichers, H.J. ; Dubois, A.E.J. ; Jong, N.W. de - \ 2017
    Clinical and Translational Allergy 7 (2017)1. - ISSN 2045-7022
    Cashew nut allergy - Children - Co-sensitisation - Food challenge test - Mango allergy - Pistachio nut allergy

    Background: Cashew nut, pistachio nut and mango belong to the Anacardiaceae family and are botanically related. Therefore, cashew nut sensitised children are frequently advised to eliminate cashew nuts and pistachio nuts from their diet. The ‘Improvement of Diagnostic mEthods for ALlergy assessment (IDEAL trial number NTR3572) study showed that cashew nut sensitised children were co-sensitised to pistachio nut in 98% of cases and to mango in 21% of cases. The aim of this follow-up study to IDEAL is to assess the clinical relevance of co-sensitisation to pistachio nut and mango in cashew nut sensitised children. Methods: Children were recruited from the study: ‘Improvement of Diagnostic mEthods for ALlergy assessment (IDEAL trial number NTR3572). Inclusion criterion for the IDEAL study was sensitization to cashew nut as demonstrated by either SPT or sIgE, and a clinical history of reactions to cashew nuts or no previous (known) exposure. Sensitized children who were tolerant to cashew nuts were excluded. Inclusion criterion for this IDEAL follow-up study was co-sensitization to pistachio nut, regardless the result of the DBPCFC with cashew nut. In this follow-up study a double-blind placebo-controlled food challenge with pistachio nut and an open food challenge with mango were performed. Results: Twenty-nine children (mean age of 11.6 years, 62% male) were included. Pistachio nut sensitisation was clinically relevant in only 34% of cashew-sensitised children and only 31% of cashew challenge positive children. None of the children was challenge positive to mango. Conclusion: Although co-sensitisation between cashew nut and pistachio nut was observed in 98%, pistachio nut sensitisation was only clinically relevant in 34% of the children. Therefore, a challenge test with pistachio nut is recommended in children with cashew nut and pistachio nut sensitisation.

    "Welcome on board" : Overall liking and just-about-right ratings of airplane meals in three different consumption contexts-laboratory, re-created airplane, and actual airplane
    Holthuysen, Nancy T.E. ; Vrijhof, Milou N. ; Wijk, René A. de; Kremer, Stefanie - \ 2017
    Journal of Sensory Studies 32 (2017)2. - ISSN 0887-8250

    The main objective of this study was to evaluate the effect of contexts on overall liking and just-about-right (JAR) ratings of airplane meals. A rice dish (meal type A) and a pasta dish (meal type B) were assessed. Per meal type, two variants were produced (variant 1 and 2). Two hundred forty-two consumers were randomly allocated to evaluate one of the four meals, first in a laboratory setting and then in a re-created airplane environment. In addition, 222 passengers did the same assessments during an actual flight. Specific meals (A1, B1) were less liked in the laboratory than in the re-created airplane. In general, no differentiation in overall liking occurred per meal type between the two tested variants in the laboratory, whereas these two variants were significantly differentiated in liking in the re-created airplane and the actual airplane. Mean overall liking ratings in the re-created airplane did not significantly differ from the mean overall liking ratings in the actual airplane. The observed JAR ratings did not differ much between the re-created airplane and the actual airplane. In summary, the re-created airplane as a testing location produced more similar test results to the actual airplane than the traditional laboratory. Practical applications: Sensory consumer testing in re-created contexts may produce results with a higher external validity than laboratory testing and therefore offer a cost-efficient alternative to extensive sensory consumer testing in real-life contexts.

    Is production intensification likely to make farm households food-adequate? A simple food availability analysis across smallholder farming systems from East and West Africa
    Ritzema, R.S. ; Frelat, R. ; Douxchamps, S. ; Silvestri, S. ; Rufino, M.C. ; Herrero, M. ; Giller, K.E. ; López-ridaura, S. ; Teufel, N. ; Paul, B.K. ; Wijk, M.T. Van - \ 2017
    Food Security 9 (2017)1. - ISSN 1876-4517 - p. 115 - 131.
    Despite considerable development investment, food insecurity remains prevalent throughout East and West Africa. The concept of ‘sustainable intensification’ of agricultural production has been promoted as a means to meet growing food needs in these regions. However, inadequate attention has been given to assessing whether benefits from intensification would be realized by farm households considering highly diverse resource endowments, household and farm characteristics, and agroecological contexts. In this study, we apply a simple energy-based index of food availability to 1800 households from research sites in 7 countries in East and West Africa to assess the food availability status of each of these households and to quantify the contribution of different on- and off-farm activities to food availability. We estimate the effects of two production intensification strategies on food availability: increased cereal crop production from crop-based options, and increased production of key livestock products from livestock-based options. These two options are contrasted with a third strategy: increased off-farm income for each household from broader socioeconomic-based options. Using sensitivity analysis, each strategy is tested against baseline values via incremental production increases. Baseline results exhibit considerable diversity within and across sites in household food availability status and livelihood strategies. Interventions represented in the crop and livestock options may primarily benefit food-adequate and marginally food-inadequate households, and have little impact on the most food-inadequate households. The analysis questions what production intensification can realistically achieve for East and West African smallholders, and how intensification strategies must be augmented with transformational strategies to reach the poorest households.
    Yield gaps in oil palm : A quantitative review of contributing factors
    Woittiez, Lotte S. ; Wijk, Mark T. van; Slingerland, Maja ; Noordwijk, Meine van; Giller, Ken E. - \ 2017
    European Journal of Agronomy 83 (2017). - ISSN 1161-0301 - p. 57 - 77.
    Intensification - Management - Palm oil - Perennial - Physiology - Yield
    Oil palm, currently the world's main vegetable oil crop, is characterised by a large productivity and a long life span (≥25 years). Peak oil yields of 12 t ha−1 yr−1 have been achieved in small plantations, and maximum theoretical yields as calculated with simulation models are 18.5 t oil ha−1 yr−1, yet average productivity worldwide has stagnated around 3 t oil ha−1 yr−1. Considering the threat of expansion into valuable rainforests, it is important that the factors underlying these existing yield gaps are understood and, where feasible, addressed. In this review, we present an overview of the available data on yield-determining, yield-limiting, and yield-reducing factors in oil palm; the effects of these factors on yield, as measured in case studies or calculated using computer models; and the underlying plant-physiological mechanisms. We distinguish four production levels: the potential, water-limited, nutrient-limited, and the actual yield. The potential yield over a plantation lifetime is determined by incoming photosynthetically active radiation (PAR), temperature, atmospheric CO2 concentration and planting material, assuming optimum plantation establishment, planting density (120–150 palms per hectares), canopy management (30–60 leaves depending on palm age), pollination, and harvesting. Water-limited yields in environments with water deficits >400 mm year−1 can be less than one-third of the potential yield, depending on additional factors such as temperature, wind speed, soil texture, and soil depth. Nutrient-limited yields of less than 50% of the potential yield have been recorded when nitrogen or potassium were not applied. Actual yields are influenced by yield-reducing factors such as unsuitable ground vegetation, pests, and diseases, and may be close to zero in case of severe infestations. Smallholders face particular constraints such as the use of counterfeit seed and insufficient fertiliser application. Closing yield gaps in existing plantations could increase global production by 15–20 Mt oil yr−1, which would limit the drive for further area expansion at a global scale. To increase yields in existing and future plantations in a sustainable way, all production factors mentioned need to be understood and addressed.
    Sensory-specific satiety: Added insights from autonomic nervous system responses and facial expressions
    He, Wei ; Boesveldt, Sanne ; Delplanque, Sylvain ; Graaf, Kees de; Wijk, René A. De - \ 2017
    Physiology and Behavior 170 (2017). - ISSN 0031-9384 - p. 12 - 18.
    As a food is consumed, its perceived pleasantness declines compared to that of other foods. Although this phenomenon, referred to as sensory-specific satiety, is well-established by means of measuring food intake and pleasantness ratings, this study was aimed at gaining more insight into the mechanisms that underlie such cognitive output behavior using two measures used in (food) emotion research, namely Autonomic Nervous System (ANS) responses and facial expressions. Twenty-four healthy female participants visited four times in a hungry state, in which they received 4 different semi-liquid meals (2 sweet and 2 savory) delivered via a time-controlled pump leading to sensory-specific satiety. Before and after the meals they were presented with a sip of all four different test meals where ANS responses (heart rate, skin conductance and skin temperature) and facial expressions were recorded. As expected, pleasantness ratings showed a significant decrease after eating the same meal or a meal similar in taste (sweet or savory) (p < 0.001), and less decrease after eating a meal with a different taste. In general, consumption of the test meals resulted in increased heart rate, reduced skin conductance and skin temperature, as well as intensified anger and disgusted facial expressions (p < 0.05). In addition, skin conductance, skin temperature, sad and angry expressions also showed effects reflecting sensory-specific satiety. In conclusion, ANS responses and facial expressions indicate that sensory specific satiety of foods 1) not only reduces the food's pleasantness but also arousal and 2) are possibly mediated by changes in food emotions.
    Modelling cereal crops to assess future climate risk for family food self-sufficiency in southern Mali
    Traore, Bouba ; Descheemaeker, Katrien ; Wijk, Mark T. van; Corbeels, Marc ; Supit, Iwan ; Giller, Ken E. - \ 2017
    Field Crops Research 201 (2017). - ISSN 0378-4290 - p. 133 - 145.
    APSIM - Climate change - Crop simulation modelling - Fertilizer use - Planting date - Sub-Saharan Africa

    Future climate change will have far reaching consequences for smallholder farmers in sub-Saharan Africa, the majority of whom depend on agriculture for their livelihoods. Here we assessed the farm-level impact of climate change on family food self-sufficiency and evaluated potential adaptation options of crop management. Using three years of experimental data on maize and millet from an area in southern Mali representing the Sudano-Sahelian zone of West Africa we calibrated and tested the Agricultural Production Systems sIMulator (APSIM) model. Changes in future rainfall, maximum and minimum temperature and their simulated effects on maize and millet yield were analysed for climate change predictions of five Global Circulation Models (GCMs) for the 4.5 Wm−2 and 8.5 Wm−2 radiative forcing scenario (rcp4.5 and rcp8.5). In southern Mali, annual maximum and minimum temperatures will increase by 2.9 °C and 3.3 °C by the mid-century (2040–2069) as compared with the baseline (1980–2009) under the rcp4.5 and rcp8.5 scenario respectively. Predicted changes in the total seasonal rainfall differed between the GCMs, but on average, seasonal rainfall was predicted not to change. By mid-century maize grain yields were predicted to decrease by 51% and 57% under current farmer's fertilizer practices in the rcp4.5 and rcp8.5 scenarios respectively. APSIM model predictions indicated that the use of mineral fertilizer at recommended rates cannot fully offset the impact of climate change but can buffer the losses in maize yield up to 46% and 51% of the baseline yield. Millet yield losses were predicted to be less severe under current farmer's fertilizer practices by mid-century i.e. 7% and 12% in the rcp4.5 and rcp8.5 scenario respectively. Use of mineral fertilizer on millet can offset the predicted yield losses resulting in yield increases under both emission scenarios. Under future climate and current cropping practices, food availability is expected to reduce for all farm types in southern Mali. However, large and medium-sized farms can still achieve food self–sufficiency if early planting and recommended rates of fertilizer are applied. Small farms, which are already food insecure, will experience a further decrease in food self-sufficiency, with adaptive measures of early planting and fertilizer use unable to help them achieve food self-sufficiency. By taking into account the diversity in farm households that is typical for the region, we illustrated that crop management strategies must be tailored to the capacity and resource endowment of local farmers. Our place-based findings can support decision making by extension and development agents and policy makers in the Sudano-Sahelian zone of West Africa.

    sIgE Ana o 1, 2 and 3 accurately distinguish tolerant from allergic children sensitized to cashew nuts
    Valk, J.P.M. van der; Gerth van Wijk, R. ; Vergouwe, Y. ; Steyerberg, E.W. ; Reitsma, M. ; Wichers, H.J. ; Savelkoul, H.F.J. ; Vlieg-Boerstra, B. ; Groot, H. de; Dubois, A.E.J. ; Jong, N.W. de - \ 2017
    Clinical and Experimental Allergy 47 (2017)1. - ISSN 0954-7894 - p. 113 - 120.
    Ana o 2 and Ana o 3 - Cashew nut allergy - Children - Component-resolved diagnosis - Components Ana o 1 - Food challenge test

    Background: The double-blind, placebo-controlled food challenge test (DBPCFC) is the gold standard in cashew nut allergy. This test is costly, time consuming and not without side effects. Analysis of IgE reactivity to cashew nut components may reduce the need for food challenge tests. Methods: In a prospective and multicentre study, children with suspected cashew nut allergy underwent a DBPCFC with cashew nut. Specific IgE to cashew nut and to the components Ana o 1, 2 and 3 were determined. A skin prick test (SPT) with cashew nut extract was performed. The association between the outcome of the food challenge test and specific IgE to Ana o 1, 2 and 3 was assessed with logistic regression analyses, unadjusted and adjusted for other diagnostic variables. Discriminative ability was quantified with a concordance index (c). Results: A total of 173 children (103 boys, 60%) with a median age of 9 years were included. About 79% had a positive challenge test outcome. A steep rise in the risk of a positive challenge was observed for specific IgE to each individual component Ana o 1, 2 and 3 with estimated risks up to approximately 100%. Median values of Ana o 1, 2, 3 were 1.29 kU/l (range 0-100 kU/l), 4.77 kU/l (range 0-100 kU/l) and 8.33 kU/l (range 0-100 kU/l) respectively and varied significantly (p <0.001). Specific IgE to Ana o 1, 2 and 3 was better distinguished between cashew-allergic and tolerant children (c = 0.87, 0.85 and 0.89, respectively) than specific IgE to cashew nut or SPT (c = 0.76 and 0.83, respectively). Conclusion: The major cashew nut allergens Ana o 1, 2 and 3 are each individually predictive for the outcome of food challenge tests in cashew-allergic children.

    Getting Emotional About Food Choice
    Wijk, Rene de; Kremer, Stefanie - \ 2016

    Emotions play a role in our food choice.
    Marketing uses this finding effectively by associating specific foods such as snacks with improved mood.

    Phosphatidic acid binding proteins display differential binding as a function of membrane curvature stress and chemical properties
    Putta, Priya ; Rankenberg, Johanna ; Korver, Ruud A. ; Wijk, Ringo van; Munnik, Teun ; Testerink, Christa ; Kooijman, Edgar E. - \ 2016
    Biochimica et Biophysica Acta. Biomembranes 1858 (2016)11. - ISSN 0005-2736 - p. 2709 - 2716.
    Epsin-like clathrin adaptor (ECA) - Liposome binding assays - Membrane curvature stress - PA target proteins - PA-binding - Phosphatidic acid - Type I and type II lipids

    Phosphatidic acid (PA) is a crucial membrane phospholipid involved in de novo lipid synthesis and numerous intracellular signaling cascades. The signaling function of PA is mediated by peripheral membrane proteins that specifically recognize PA. While numerous PA-binding proteins are known, much less is known about what drives specificity of PA-protein binding. Previously, we have described the ionization properties of PA, summarized in the electrostatic-hydrogen bond switch, as one aspect that drives the specific binding of PA by PA-binding proteins. Here we focus on membrane curvature stress induced by phosphatidylethanolamine and show that many PA-binding proteins display enhanced binding as a function of negative curvature stress. This result is corroborated by the observation that positive curvature stress, induced by lyso phosphatidylcholine, abolishes PA binding of target proteins. We show, for the first time, that a novel plant PA-binding protein, Arabidopsis Epsin-like Clathrin Adaptor 1 (ECA1) displays curvature-dependence in its binding to PA. Other established PA targets examined in this study include, the plant proteins TGD2, and PDK1, the yeast proteins Opi1 and Spo20, and, the mammalian protein Raf-1 kinase and the C2 domain of the mammalian phosphatidylserine binding protein Lact as control. Based on our observations, we propose that liposome binding assays are the preferred method to investigate lipid binding compared to the popular lipid overlay assays where membrane environment is lost. The use of complex lipid mixtures is important to elucidate further aspects of PA binding proteins.

    Methods for environment: Productivity trade-off analysis in agricultural systems
    Wijk, M.T. van; Klapwijk, C.J. ; Rosenstock, T.S. ; Asten, P.J.A. van; Thornton, P.K. ; Giller, K.E. - \ 2016
    In: Methods for Measuring Greenhouse Gas Balances and Evaluating Mitigation Options in Smallholder Agriculture / , T.S. Rosenstock, Rufino, M.C., Butterbach-Bahl, K., Wollenberg, E., Richards, M., Cham : Springer International Publishing - ISBN 9783319297927 - p. 189 - 198.
    Trade-off analysis has become an increasingly important approach for evaluating system level outcomes of agricultural production and for prioritising and targeting management interventions in multi-functional agricultural landscapes. We review the strengths and weakness of different techniques available for performing trade-off analysis. These techniques, including mathematical programming and participatory approaches, have developed substantially in recent years aided by mathematical advancement, increased computing power, and emerging insights into systems behaviour. The strengths and weaknesses of the different approaches are identified and discussed, and we make suggestions for a tiered approach for situations with different data availability.
    Groenten uit de stad
    Valk, Arnold van der - \ 2016
    urban agriculture - urban areas - health - social welfare - participation - volunteers

    Stadslandbouw geeft niet alleen een krachtige impuls aan de leefbaarheid van de wijk, maar kan ook een positieve bijdrage leveren aan de gezondheid. Hoe komen buurtprojecten voor stadslandbouw tot stand en wanneer zijn ze succesvol? AGORA ging hierover in gesprek met onderzoekers Beatriz Pineda Revilla (Universiteit van Amsterdam) en Arnold van der Valk (Wageningen Universiteit.

    Co-evolution of smart energy products and services: A novel approach towards smart grids
    Reinders, Angele ; Respinis, Moreno de; Loon, Jorien van; Stekelenburg, Anton ; Bliek, Frits ; Schram, Wouter ; Sark, Wilfried van; Esteri, Tara ; Uebermasser, Stefan ; Lehfuss, Felix ; Gultekin, Esin ; Mierlo, Barbara Van; Markocic, Elena ; Hassewend, Brigitte ; Robledo, Carla ; Papaioannou, Ioulia ; Wijk, Ad van; Lagler, Mike ; Schmautzer, Ernst ; Hohn, Thomas ; Fickert, Lothar - \ 2016
    In: 2016 Asian Conference on Energy, Power and Transportation Electrification, ACEPT 2016 IEEE - 6 p.
    In this paper we present our project on interdisciplinary evaluations of existing smart grid environments regarding (1) the technical performance of smart energy products and services, (2) end users perceptions, (3) stakeholder processes and (4) market aspects. Our evaluations are based on data and information originating from real life pilots and demonstration projects in the field of smart grids in residential areas in the Netherlands and in Austria. The so-called CESEPS project is executed in the European ERA-Net Smart Grids Plus program. CESEPS stands for Co-Evolution of Smart Energy Product and Services. Its main objective is to support the development of smart energy products and services for local smart grids that better respond to the demands and concerns of all stakeholders in terms of performance, cost, reliability, safety and robustness, sustainability and energy-efficiency, and end users' comfort. Besides comparative data analyses and user surveys, this three year project comprises simulation activities to model existing and innovative smart grid energy products to evaluate their feasibility, given the aspects above mentioned. In this paper our approach will be explained and illustrated by several examples of ongoing subtopics of research and knowledge dissemination among stakeholders in the smart grid sector.
    Beweeg- en sportstimulering door professionals in de wijk : Rapportage van de resultaten van een Delphi studie
    Smit, E. ; Leenaars, K.E.F. ; Wagemakers, M.A.E. ; Molleman, G.R.M. - \ 2016
    Radboudumc en Wageningen Universiteit
    A review of efforts to integrate nutrition in systems research
    Raneri, Jessica ; Ritzema, Randall ; Nga, Le Thi ; Yang, Ray-Yu ; Groot, J.C.J. ; Kae, Christina ; Bolliger, Adrian ; Chau, Long ; Hammond, James ; Wijk, Mark T. van; Kennedy, Gina - \ 2016
    In: Integrated Systems Research for Sustainable Smallholder Agriculture in the Central Mekong / Hiwasaki, L., Bolliger, A., Lacombe, G., Raneri, J., Schut, M., Staal, S., Hanoi, Viet Nam : World Agroforestry Centre - ISBN 9786049434341 - p. 65 - 99.
    What Works Where for Whom? Farm Household Strategies for Food Security Across Uganda
    Wichern, J. ; Wijk, M.T. van; Descheemaeker, K.K.E. ; Heerwaarden, J. van; Frelat, Romain ; Giller, K.E. - \ 2016
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