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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    Considering a healthy future : effects of time orientation on eating and exercising behavior
    Beek, Jannette van - \ 2016
    Wageningen University. Promotor(en): Gerrit Antonides, co-promotor(en): Michel Handgraaf. - Wageningen : Wageningen University - ISBN 9789462579286 - 167
    exercise - health behaviour - time - food preferences - future - eating patterns - lichaamsbeweging - gezondheidsgedrag - tijd - voedselvoorkeuren - toekomst - eetpatronen

    Trade-offs between current and future consequences are characteristic for the domain of health behavior. Therefore, both eating and exercising behavior could be determined by time orientation, which refers to an individual’s general orientation toward the present or the future. The main aim of this dissertation is to provide insight into the relations between time orientation and both eating and exercising behavior. The results of this dissertation confirm that time orientation is a shared determinant of eating and exercising behavior. Nevertheless, time orientation for food and for exercise are different constructs that, in turn, have differential relations with eating and exercising behavior. Specifically, eating behavior is mainly predicted by consideration of immediate consequences, whereas exercising behavior is mainly predicted by consideration of future consequences. In addition, these relations can be partly explained by construal level. Theoretically, the results of this dissertation contribute in various ways to a better understanding of the construct of time orientation and its relations with eating and exercising behavior. Methodologically, the results of this dissertation have several implications for the measurement of time orientation as well as the measurement of eating and exercising behavior. Practically, the results of this dissertation can be used in the development of campaigns to stimulate healthy eating and exercising behavior. Overall, the insights that have been gained in this dissertation contribute to a better understanding of individuals’ intertemporal decision making in the health domain and can ultimately be used in order to promote and stimulate healthy eating and exercising behavior.

    Modeling an inventory routing problem for perishable products with environmental considerations
    Soysal, M. ; Bloemhof, J.M. ; Haijema, R. ; Vorst, J.G.A.J. van der - \ 2015
    International Journal of Production Economics 164 (2015). - ISSN 0925-5273 - p. 118 - 133.
    service-level constraints - transshipment - heuristics - systems - stock - time
    The transition to sustainable food supply chain management has brought new key logistical aims such as reducing food waste and environmental impacts of operations in the supply chain besides the traditional cost minimization objective. Traditional assumptions of constant distribution costs between nodes, unlimited product shelf life and deterministic demand used in the Inventory Routing Problem (IRP) literature restrict the usage of the proposed models in current food logistics systems. From this point of view, our interest in this study is to enhance the traditional models for the IRP to make them more useful for the decision makers in food logistics management. Therefore, we present a multi-period IRP model that includes truck load dependent (and thus route dependent) distribution costs for a comprehensive evaluation of CO2 emission and fuel consumption, perishability, and a service level constraint for meeting uncertain demand. A case study on the fresh tomato distribution operations of a supermarket chain shows the applicability of the model to a real-life problem. Several variations of the model, each differing with respect to the considered aspects, are employed to present the benefits of including perishability and explicit fuel consumption concerns in the model. The results suggest that the proposed integrated model can achieve significant savings in total cost while satisfying the service level requirements and thus offers better support to decision makers.
    Experimental illumination of natural habitat - an experimental set-up to assess the direct and indirect ecological consequences of artificial light of different spectral composition
    Spoelstra, K. ; Grunsven, R.H.A. van; Donners, M. ; Huijgens, T. ; Slaterus, R. ; Berendse, F. ; Visser, M.E. ; Veenendaal, E.M. - \ 2015
    Philosophical Transactions of the Royal Society B. Biological sciences 370 (2015). - ISSN 0962-8436 - 8 p.
    predation risk - beach mice - bats - night - ultraviolet - wavelength - pollution - responses - vision - time
    Artificial night-time illumination of natural habitats has increased dramatically over the past few decades. Generally, studies that assess the impact of artificial light on various species in the wild make use of existing illumination and are therefore correlative. Moreover, studies mostly focus on short-term consequences at the individual level, rather than long-term consequences at the population and community level—thereby ignoring possible unknown cascading effects in ecosystems. The recent change to LED lighting has opened up the exciting possibility to use light with a custom spectral composition, thereby potentially reducing the negative impact of artificial light. We describe here a large-scale, ecosystem-wide study where we experimentally illuminate forest-edge habitat with different spectral composition, replicated eight times. Monitoring of species is being performed according to rigid protocols, in part using a citizen-science-based approach, and automated where possible. Simultaneously, we specifically look at alterations in behaviour, such as changes in activity, and daily and seasonal timing. In our set-up, we have so far observed that experimental lights facilitate foraging activity of pipistrelle bats, suppress activity of wood mice and have effects on birds at the community level, which vary with spectral composition. Thus far, we have not observed effects on moth populations, but these and many other effects may surface only after a longer period of time.
    Hypothesis: the sound of the individual metabolic phenotype? Acoustic detection of NMR experiments
    Cacciatore, S. ; Saccenti, E. ; Piccioli, M. - \ 2015
    OMICS - A Journal of Integrative Biology 19 (2015)3. - ISSN 1536-2310 - p. 147 - 156.
    breast-cancer - personalized medicine - disease - profiles - models - health - time - classification - identification - metabonomics
    We present here an innovative hypothesis and report preliminary evidence that the sound of NMR signals could provide an alternative to the current representation of the individual metabolic fingerprint and supply equally significant information. The NMR spectra of the urine samples provided by four healthy donors were converted into audio signals that were analyzed in two audio experiments by listeners with both musical and non-musical training. The listeners were first asked to cluster the audio signals of two donors on the basis of perceived similarity and then to classify unknown samples after having listened to a set of reference signals. In the clustering experiment, the probability of obtaining the same results by pure chance was 7.04% and 0.05% for non-musicians and musicians, respectively. In the classification experiment, musicians scored 84% accuracy which compared favorably with the 100% accuracy attained by sophisticated pattern recognition methods. The results were further validated and confirmed by analyzing the NMR metabolic profiles belonging to two other different donors. These findings support our hypothesis that the uniqueness of the metabolic phenotype is preserved even when reproduced as audio signal and warrants further consideration and testing in larger study samples
    Dynamic texture perception and oral processing of semi-solid food gels: Part 1: Comparison between QDA, progressive profiling and TDS
    Devezeaux de Lavergne, M.S.M. ; Delft, J.M. van; Velde, F. van de; Boekel, M.A.J.S. van; Stieger, M.A. - \ 2015
    Food Hydrocolloids 43 (2015). - ISSN 0268-005X - p. 207 - 217.
    emulsion-filled gels - sensory texture - rheological properties - mechanical-properties - temporal dominance - time - microstructure - sensations
    Texture perception of food is a dynamic phenomenon depending on food properties and oral processing. Several sensory techniques enable to measure texture perception over time. The aim of this study was to compare quantitative descriptive analysis (QDA), temporal dominance of sensation (TDS) and progressive profiling in the assessment of dynamic texture of emulsion filled gels varying in fracture stress (low/high), fracture strain (low/high) and oil release (oil droplets bound/unbound to the gel matrix). The QDA results revealed that the variation of mechanical properties led to significant differences in texture properties perceived at first bite (firmness and brittleness). Texture attributes perceived at later stages of mastication showed significant differences between gels depending on the first bite properties e.g. soft gels were perceived as more melting. Progressive profiling showed that creaminess increased over eating time while firmness decreased. TDS results were in agreement with the other methods and additionally conveyed information on the succession of perceived attributes over time. The TDS sensory trajectories demonstrated that for all gels dynamic perception evolved in a similar fashion but samples with a high or low fracture strain differed at the end of oral processing. We conclude that texture perception of semi-solid gels is dynamic and can be measured by either of the three sensory methods. The mechanical properties of the gels influence the perception of texture attributes at first bite and at later stages of mastication. QDA, TDS and progressive profiling gave matching and complementary results in the assessment of dynamic sensory texture.
    The effect of product–context appropriateness on emotion associations in evoked eating occasions
    Piqueras Fiszman, B. ; Jaeger, S.R. - \ 2015
    Food Quality and Preference 40 (2015)Part A. - ISSN 0950-3293 - p. 49 - 60.
    food choice - consumption contexts - acceptability - responses - experience - situation - ratings - impact - liking - time
    The aim of this research was to investigate the impact that perceived product–context appropriateness exerts on elicited emotion associations. The experimental approach consisted in creating eating occasions (as a multi-component entity) varying in appropriateness, which consumers were instructed to vividly imagine while they completed emotion surveys for selected products. Multiple studies were purposefully designed to include different products, contextual dimensions (comprising internal and external conditions) and presentation formats, consumer populations, test locations, and emotion survey formats. The results from 1336 consumers consistently revealed an effect of appropriateness on the emotion associations toward food products and eating occasions. The frequency and intensity of positive emotion terms was generally higher with more appropriate contexts, decreasing with the appropriateness ratings (and vice versa for the negative emotion terms). In addition, the impact of perceived appropriateness was asymmetrical, having a stronger impact on positive than on negative emotion terms. These insights support the idea that emotion responses are subject to a large number of contextual influences, and make a robust case for including appropriateness measures in context and emotion research.
    Mapping ecosystem services: The supply and demand of flood regulation services in Europe
    Sturck, J. ; Poortinga, A. ; Verburg, P.H. - \ 2014
    Ecological Indicators 38 (2014). - ISSN 1470-160X - p. 198 - 211.
    land-use changes - climate-change - changing climate - runoff - soil - protection - catchments - forests - areas - time
    Ecosystem services (ES) feature highly distinctive spatial and temporal patterns of distribution, quantity, and flows. The flow of ecosystem goods and services to beneficiaries plays a decisive role in the valuation of ES and the successful implementation of the ES concept in environmental planning. This is particularly relevant to regulating services where demands emerge often spatially separated from supply. However, spatial patterns of both supply and demand are rarely incorporated in ES assessments on continental scales. In this paper, we present an ES modeling approach with low data demand, fit to be employed in scenario analysis and on multiple scales. We analyze flood regulation services at a European scale by explicitly addressing the spatial distribution of ES demand. A flood regulation supply indicator is developed based on scenario runs with a hydrological model in representative river catchments, incorporating detailed information on land, cover, land use and management. Land use sensitive flood damage estimates in the European Union (EU) are employed to develop a spatial indicator for flood regulation demand. Findings are transferred to the EU territory to create a map of the current supply of flood regulation and the potential supply under conditions of natural vegetation. Regions with a high capacity to provide flood regulation are mainly characterized by large patches of natural vegetation or extensive agriculture. The main factor limiting supply on a continental scale is a low water holding capacity of the soil. Flood regulation demand is highest in central Europe, at the foothills of the Alps and upstream of agglomerations. We were able to identify areas with a high potential capacity to provide flood regulation in conjunction with land use modifications. When combined with spatial patterns of current supply and demand, we could identify priority areas for investments in ES flood regulation supply through conservation and land use planning. We found that only in a fraction of the EU river catchments exhibiting a high demand, significant increases in flood regulation supply are achievable by means of land use modifications. (C) 2013 Elsevier Ltd. All rights reserved.
    Inconsistency of Phenotypic and Genomic Characteristics of Campylobacter fetus Subspecies Requires Reevaluation of Current Diagnostics
    Bloois, L. van; Miller, W.G. ; Yee, E. ; Rijnsburger, M. ; Wagenaar, J.A. ; Duim, B. - \ 2014
    Journal of Clinical Microbiology 52 (2014)12. - ISSN 0095-1137 - p. 4183 - 4188.
    pcr assay - identification - time
    Classifications of the Campylobacter fetus subspecies fetus and venerealis were first described in 1959 and were based on the source of isolation (intestinal versus genital) and the ability of the strains to proliferate in the genital tract of cows. Two phenotypic assays (1% glycine tolerance and H2S production) were described to differentiate the subspecies. Multiple molecular assays have been applied to differentiate the C. fetus subspecies, but none of these tests is consistent with the phenotypic identification methods. In this study, we defined the core genome and accessory genes of C. fetus, which are based on the closed genomes of five C. fetus strains. Phylogenetic analysis of the core genomes of 23 C. fetus strains of the two subspecies showed a division into two clusters. The phylogenetic core genome clusters were not consistent with the phenotypic classifications of the C. fetus subspecies. However, they were consistent with the molecular characteristics of the strains, which were determined by multilocus sequence typing, sap typing, and the presence/absence of insertion sequences and a type I restriction modification system. The similarity of the genome characteristics of three of the phenotypically defined C. fetus subsp. fetus strains to C. fetus subsp. venerealis strains, when considering the core genome and accessory genes, requires a critical evaluation of the clinical relevance of C. fetus subspecies identification by phenotypic assays.
    Application of the Taguchi method in poultry science: estimation of the in vitro optimum intrinsic phytase activity of rye, wheat and barley
    Sedghi, M. ; Golian, A. ; Esmaeilipour, O. ; Krimpen, M.M. van - \ 2014
    British Poultry Science 55 (2014)2. - ISSN 0007-1668 - p. 246 - 252.
    experimental-design - optimization - stability - culture - time - ph
    1. In poultry investigations, the main interest is often to study the effects of many factors simultaneously. Two or three level factorial designs are the most commonly used for this type of investigation. However, it is often too costly to perform when number of factors increase. So a fractional factorial design, which is a subset or a fraction of a full factorial design, is an alternative. The Taguchi method has been proposed for simplifying and standardising fractional factorial designs. 2. An experiment was conducted to evaluate the applicability of the Taguchi method to optimise in vitro intrinsic phytase activity (IPA) of rye, wheat and barley under different culture conditions. 3. In order to have a solid base for judging the suitability of the Taguchi method, the results of the Taguchi method were compared with those of an experiment that was conducted as a 34 full factorial arrangement with three feed ingredients (rye, wheat and barley), three temperatures (20 degrees C, 38 degrees C and 55 degrees C), three pH values (3.0, 5.5 and 8.0) and three incubation times (30, 60 and 120 min), with two replicates per treatment. 4. After data collection, a Taguchi L 9 (3(4)) orthogonal array was used to estimate the effects of different factors on the IPA, based on a subset of only 9 instead of 81 treatments. The data were analysed with both Taguchi and full factorial methods and the main effects and the optimal combinations of these 4 factors were obtained for each method. 5. The results indicated that according to both the full factorial experimental design and the Taguchi method, the optimal culture conditions were obtained with the following combination: rye, pH = 3, temperature = 20 degrees C and time of incubation = 30 min. The comparison between the Taguchi and full factorial results showed that the Taguchi method is a sufficient and resource saving alternative to the full factorial design in poultry science.
    Sensitivity of power functions to aggregation: bias and uncertainty in radar rainfall retrieval
    Sassi, M.G. ; Leijnse, H. ; Uijlenhoet, R. - \ 2014
    Water Resources Research 50 (2014)10. - ISSN 0043-1397 - p. 8050 - 8065.
    zero-rainfall - semi-variance - resolution - hydrology - time - multifractals - distributions - attenuation - variability - netherlands
    Rainfall retrieval using weather radar relies on power functions between radar reflectivity Z and rain rate R. The nonlinear nature of these relations complicates the comparison of rainfall estimates employing reflectivities measured at different scales. Transforming Z into R using relations that have been derived for other scales results in a bias and added uncertainty. We investigate the sensitivity of Z-R relations to spatial and temporal aggregation using high-resolution reflectivity fields for five rainfall events. Existing Z-R relations were employed to investigate the behavior of aggregated Z-R relations with scale, the aggregation bias, and the variability of the estimated rain rate. The prefactor and the exponent of aggregated Z-R relations systematically diverge with scale, showing a break that is event-dependent in the temporal domain and nearly constant in space. The systematic error associated with the aggregation bias at a given scale can become of the same order as the corresponding random error associated with intermittent sampling. The bias can be constrained by including information about the variability of Z within a certain scale of aggregation, and is largely captured by simple functions of the coefficient of variation of Z. Several descriptors of spatial and temporal variability of the reflectivity field are presented, to establish the links between variability descriptors and resulting aggregation bias. Prefactors in Z-R relations can be related to multifractal properties of the rainfall field. We find evidence of scaling breaks in the structural analysis of spatial rainfall with aggregation.
    Of Monkeys and Men: A Metabolomic Analysis of Static and Dynamic Urinary Metabolic Phenotypes in Two Species
    Saccenti, E. ; Tenori, L. ; Verbruggen, P. ; Timmerman, M.E. ; Bouwman, J. ; Greef, J. de; Luchinat, C. ; Smilde, A.K. - \ 2014
    PLoS ONE 9 (2014)9. - ISSN 1932-6203
    multilevel component analysis - time - creatinine - evolution - pathways - humans - diet
    Background Metabolomics has attracted the interest of the medical community for its potential in predicting early derangements from a healthy to a diseased metabolic phenotype. One key issue is the diversity observed in metabolic profiles of different healthy individuals, commonly attributed to the variation of intrinsic (such as (epi)genetic variation, gut microbiota, etc.) and extrinsic factors (such as dietary habits, life-style and environmental conditions). Understanding the relative contributions of these factors is essential to establish the robustness of the healthy individual metabolic phenotype. Methods To assess the relative contribution of intrinsic and extrinsic factors we compared multilevel analysis results obtained from subjects of Homo sapiens and Macaca mulatta, the latter kept in a controlled environment with a standardized diet by making use of previously published data and results. Results We observed similarities for the two species and found the diversity of urinary metabolic phenotypes as identified by nuclear magnetic resonance (NMR) spectroscopy could be ascribed to the complex interplay of intrinsic factors and, to a lesser extent, of extrinsic factors in particular minimizing the role played by diet in shaping the metabolic phenotype. Moreover, we show that despite the standardization of diet as the most relevant extrinsic factor, a clear individual and discriminative metabolic fingerprint also exists for monkeys. We investigate the metabolic phenotype both at the static (i.e., at the level of the average metabolite concentration) and at the dynamic level (i.e., concerning their variation over time), and we show that these two components sum up to the overall phenotype with different relative contributions of about 1/4 and 3/4, respectively, for both species. Finally, we show that the great degree diversity observed in the urinary metabolic phenotype of both species can be attributed to differences in both the static and dynamic part of their phenotype
    A genetic linkage map of Sole (Solea solea): A tool for evolutionary and comparative analyses of exploited (flat)fishes
    Diopere, E. ; Maes, G.E. ; Komen, J. ; Volckaert, F.A.M. ; Groenen, M. - \ 2014
    PLoS ONE 9 (2014)12. - ISSN 1932-6203 - 16 p.
    turbot scophthalmus-maximus - common sole - microsatellite markers - comparative genomics - marine fishes - populations - time - divergence - pleuronectiformes - senegalensis
    Linkage maps based on markers derived from genes are essential evolutionary tools for commercial marine fish to help identify genomic regions associated with complex traits and subject to selective forces at play during exploitation or selective breeding. Additionally, they allow the use of genomic information from other related species for which more detailed information is available. Sole (solea solea L.) is a commercially important flatfish species in the North Sea, subject to overexploitation and showing evidence of fisheries-induced evolutionary changes in growth- and maturation-related traits. Sole would definitely benefit from a linkage map to better understand how evolution has shaped its genome structure. This study presents a linkage map of sole based on 423 single nucleotide polymorphisms derived from expressed sequence tags and 8 neutral microsatellite markers. The total map length is 1233.8 cM and consists of 38 linkage groups with a size varying between 0 to 92.1 cM. Being derived from expressed sequence tags allowed us to align the map with the genome of four model fish species, namely medaka (Oryzias latipes), Nile tilapia (Oreochromis niloticus), three-spined stickleback (Gasterosteus aculeatus) and green spotted pufferfish (Tetraodon nigroviridis). This comparison revealed multiple conserved syntenic regions with all four species, and suggested that the linkage groups represent 21 putative sole chromosomes. The map was also compared to the linkage map of turbot (Scophthalmus maximus), another commercially important flatfish species and closely related to sole. For all putative sole chromosomes (except one) a turbot homolog was detected, confirming the even higher degree of synteny between these two flatfish species.
    Approaches to defining a planetary boundary for biodiversity
    Mace, G.M. ; Reyers, B. ; Alkemade, R. ; Biggs, R. ; Stuart Chapin, F. ; Cornell, S.E. ; Diaz, S. - \ 2014
    Global environmental change : human and policy dimensions 28 (2014). - ISSN 0959-3780 - p. 289 - 297.
    plant functional traits - global biodiversity - ecosystem services - phylogenetic diversity - tree mortality - tipping points - conservation - extinction - time - biosphere
    The idea that there is an identifiable set of boundaries, beyond which anthropogenic change will put the Earth system outside a safe operating space for humanity, is attracting interest in the scientific community and gaining support in the environmental policy world. Rockstrom et al. (2009) identify nine such boundaries and highlight biodiversity loss as being the single boundary where current rates of extinction put the Earth system furthest outside the safe operating space. Here we review the evidence to support a boundary based on extinction rates and identify weaknesses with this metric and its bearing on humanity's needs. While changes to biodiversity are of undisputed importance, we show that both extinction rate and species richness are weak metrics for this purpose, and they do not scale well from local to regional or global levels. We develop alternative approaches to determine biodiversity loss boundaries and extend our analysis to consider large-scale responses in the Earth system that could affect its suitability for complex human societies which in turn are mediated by the biosphere. We suggest three facets of biodiversity on which a boundary could be based: the genetic library of life; functional type diversity; and biome condition and extent. For each of these we explore the science needed to indicate how it might be measured and how changes would affect human societies. In addition to these three facets, we show how biodiversity's role in supporting a safe operating space for humanity may lie primarily in its interactions with other boundaries, suggesting an immediate area of focus for scientists and policymakers.
    Vitality of the General Food: Wear and tear of the substantive approach to food
    Meulen, B.M.J. van der - \ 2014
    Journal für Verbraucherschutz und Lebensmittelsicherheit 9 (2014). - ISSN 1661-5751 - p. 414 - 417.
    escherichia-coli o157 - manure-amended soil - mass-spectrometry - survival - incision - bovine - origin - time
    Genetic divergence and evidence for sympatric host-races in the highly polyphagous brown tail moth, Euproctis chrysorrhoea (Lepidoptera: Erebidae)
    Marques, J.F. ; Wang, H.L. ; Svensson, G.P. ; Frago Clols, E. ; Anderbrant, O. - \ 2014
    Evolutionary Ecology 28 (2014)5. - ISSN 0269-7653 - p. 829 - 848.
    plant-feeding insects - tree arbutus-unedo - evolutionary history - mitochondrial - populations - speciation - refugia - time - diversification - differentiation
    The brown tail moth (BTM) Euproctis chrysorrhoea (Linnaeus 1758) (Lepidoptera: Erebidae) is a forest and ornamental pest in Europe and the United States. Its extreme polyphagy, and documented phenological shift associated with host use suggest the presence of distinct host-races. To test this hypothesis, we sampled BTM infesting different host species in several locations along its distribution, and used DNA sequence data (a total of 1,672 bp from cytochrome c oxidase subunit I, elongation factor 1-alpha, and wingless) to produce haplotype networks and reconstruct the phylogenetic relationships between individuals. Population genetic diversity indices pointed out a higher genetic diversity in Europe, particularly in the samples from southern Spain and southern England. Lower F ST values were found between geographically closer populations when compared to more distant ones, but analyses of molecular variance and Mantel tests failed to reveal geographically associated genetic differentiation. However, haplotype networks and phylogenetic reconstructions revealed a previously unknown genetic differentiation within the BTM, with one lineage circumscribed to southern Europe. Although BTM haplotypes did not cluster according to their host plant, host-associated haplotypes were observed within certain geographic regions. Hence, our data support the existence of host-races of BTM within southern Spain and southern England, where populations from different hosts occur in sympatry.
    Quantifying levels of animal activity using camera trap data
    Rowcliffe, J.M. ; Kays, R. ; Kranstauber, B. ; Carbone, C. ; Jansen, P.A. - \ 2014
    Methods in Ecology and Evolution 5 (2014)11. - ISSN 2041-210X - p. 1170 - 1179.
    home-range size - predator avoidance - circadian activity - microtus-arvalis - activity pattern - common vole - time - food - determinants - ecology
    1.Activity level (the proportion of time that animals spend active) is a behavioural and ecological metric that can provide an indicator of energetics, foraging effort and exposure to risk. However, activity level is poorly known for free-living animals because it is difficult to quantify activity in the field in a consistent, cost-effective and non-invasive way. 2.This article presents a new method to estimate activity level with time-of-detection data from camera traps (or more generally any remote sensors), fitting a flexible circular distribution to these data to describe the underlying activity schedule, and calculating overall proportion of time active from this. 3.Using simulations and a case study for a range of small- to medium-sized mammal species, we find that activity level can reliably be estimated using the new method. 4.The method depends on the key assumption that all individuals in the sampled population are active at the peak of the daily activity cycle. We provide theoretical and empirical evidence suggesting that this assumption is likely to be met for many species, but may be less likely met in large predators, or in high-latitude winters. Further research is needed to establish stronger evidence on the validity of this assumption in specific cases; however, the approach has the potential to provide an effective, non-invasive alternative to existing methods for quantifying population activity levels.
    Stimulation of colonic motility by oral PEG electrolyte bowel preparation assessed by MRI: comparison of split vs single dose
    Marciani, L. ; Garsed, K.C. ; Hoad, C.L. ; Fields, A. ; Fordham, I. ; Pritchard, S.E. ; Placidi, E. ; Murray, K. ; Chaddock, G. ; Costigan, C. ; Lam, C. ; Jalanka-Tuovinen, J. ; Vos, W.M. de; Gowland, P.A. ; Spiller, R.C. - \ 2014
    Neurogastroenterology & Motility 26 (2014)10. - ISSN 1365-2982 - p. 1426 - 1436.
    randomized controlled-trial - whole-gut transit - water-content - polyethylene-glycol - gastric-motility - healthy-subjects - ascorbic-acid - colonoscopy - time - constipation
    Background Most methods of assessing colonic motility are poorly acceptable to patients. Magnetic resonance imaging (MRI) can monitor gastrointestinal motility and fluid distributions. We predicted that a dose of oral polyethylene glycol (PEG) and electrolyte solution would increase ileo-colonic inflow and stimulate colonic motility. We aimed to investigate the colonic response to distension by oral PEG electrolyte in healthy volunteers (HVs) and to evaluate the effect of single 2 L vs split (2 × 1 L) dosing. Methods Twelve HVs received a split dose (1 L the evening before and 1 L on the study day) and another 12 HVs a single dose (2 L on the main study day) of PEG electrolyte. They underwent MRI scans, completed symptom questionnaires, and provided stool samples. Outcomes included small bowel water content, ascending colon motility index, and regional colonic volumes. Key Results Small bowel water content increased fourfold from baseline after ingesting both split (p = 0.0010) and single dose (p = 0.0005). The total colonic volume increase from baseline was smaller for the split dose at 35 ± 8% than for the single dose at 102 ± 27%, p = 0.0332. The ascending colon motility index after treatment was twofold higher for the single dose group (p = 0.0103). Conclusions & Inferences Ingestion of 1 and 2 L PEG electrolyte solution caused a rapid increase in the small bowel and colonic volumes and a robust rise in colonic motility. The increase in both volumes and motility was dose dependent. Such a challenge, being well-tolerated, could be a useful way of assessing colonic motility in future studies.
    Visualizing stakeholder perspectives for reflection and dialogue on scale dynamics in social–ecological systems
    Vervoort, J.M. ; Hoogstra, M.A. ; Kok, K. ; Lammeren, R.J.A. van; Bregt, A.K. ; Janssen, R. - \ 2014
    Human Ecology Review 20 (2014)2. - ISSN 1074-4827 - p. 157 - 181.
    scenario development - global change - time - capacity - limits
    An understanding among societal actors of how social–ecological systems interact across multiple levels and scales contributes to better governance of those systems. This paper introduces a tool, Scale Perspectives, developed to help societal actors share their perspectives on issues of social–ecological systems governance in a multilevel framework. A first version showed that participants in a local and European case study associated a diverse range of levels and time frames with the same issues, but the version was not able to capture cross-level dynamics. A second version of the tool did allow for the visualization of cross-level dynamics, and was tested in live workshops where more opportunities for individual and group reflection were offered. The tool proved useful for sharing perspectives and strategic dialogue among the participants. The results show the potential of such tools to help societal actors tackle challenges related to scale dynamics in social–ecological systems governance.
    Evaluation of Different Cooking Conditions on Broccoli (Brassica oleracea var. italica) to Improve the Nutritional Value and Consumer Acceptance
    Bongoni, R. ; Verkerk, R. ; Steenbekkers, B. ; Dekker, M. ; Stieger, M.A. - \ 2014
    Plant Foods for Human Nutrition 69 (2014)3. - ISSN 0921-9668 - p. 228 - 234.
    antioxidant capacity - vegetables - texture - health - cabbage - time
    This paper reviews the main results of EU-action: “COST 926: Impact of new technologies on the health benefits and safety of bioactive plant compounds”. The bioavailability and the effects on gene expression of various bioactive components in plant foods are described in relation with their implication for human health. The objective of this study was to gain insights into the effect of the cooking method on the liking as well as the retention of glucosinolates in broccoli. With this knowledge it can be concluded whether the health aspects of broccoli be improved by the cooking method without deteriorating sensory perception. For this, broccoli was cooked by methods commonly applied by consumers: boiling with a cold (water) start; boiling with a hot (water) start; and steaming. Firmness, greenness and amount of total glucosinolates in cooked broccoli were instrumentally determined. Sensory evaluation by untrained consumers (n¿=¿99) for liking and sensory attributes intensity rating were performed on broccoli cooked by steaming and boiling-cold start at three time points, which resulted in ‘high’, ‘medium’, ‘low’ firm broccoli samples. At the end of cooking, steaming showed an increase in the amount of total glucosinolates (+17 %). Boiling-hot start (-41 %) and boiling-cold start (-50 %) showed a decrease in amount of total glucosinolates. Sensory evaluation did not show statistically significant differences between steaming and boiling-cold start in liking at ‘high’ and ‘medium’ firmness; and in the attribute intensity ratings (except for juiciness at ‘medium’ firmness, and flavour at ‘medium’ and ‘low’ firmness). This study demonstrates that medium firm broccoli showed optimum liking and that steaming compared to boiled-cold start showed higher amount of glucosinolates. It is concluded that the health aspects of broccoli can be improved without reducing the sensory aspects by optimising the cooking method.
    Identification, cloning and characterization of the tomato TCP transcription factor family
    Parapunova, V.A. ; Busscher, M. ; Busscher-Lange, J. ; Lammers, M. ; Karlova, R.B. ; Bovy, A.G. ; Angenent, G.C. ; Maagd, R.A. de - \ 2014
    BMC Plant Biology 14 (2014). - ISSN 1471-2229
    mads-box gene - arabidopsis-thaliana - fruit-development - leaf development - high-throughput - plant-growth - dna-binding - expression - time - interference
    Background: TCP proteins are plant-specific transcription factors, which are known to have a wide range of functions in different plant species such as in leaf development, flower symmetry, shoot branching, and senescence. Only a small number of TCP genes has been characterised from tomato (Solanum lycopersicum). Here we report several functional features of the members of the entire family present in the tomato genome. Results: We have identified 30 Solanum lycopersicum SlTCP genes, most of which have not been described before. Phylogenetic analysis clearly distinguishes two homology classes of the SlTCP transcription factor family - class I and class II. Class II differentiates in two subclasses, the CIN-TCP subclass and the CYC/TB1 subclass, involved in leaf development and axillary shoots formation, respectively. The expression patterns of all members were determined by quantitative PCR. Several SlTCP genes, like SlTCP12, SlTCP15 and SlTCP18 are preferentially expressed in the tomato fruit, suggesting a role during fruit development or ripening. These genes are regulated by RIN (RIPENING INHIBITOR), CNR (COLORLESS NON-RIPENING) and SlAP2a (APETALA2a) proteins, which are transcription factors with key roles in ripening. With a yeast one-hybrid assay we demonstrated that RIN binds the promoter fragments of SlTCP12, SlTCP15 and SlTCP18, and that CNR binds the SlTCP18 promoter. This data strongly suggests that these class I SlTCP proteins are involved in ripening. Furthermore, we demonstrate that SlTCPs bind the promoter fragments of members of their own family, indicating that they regulate each other. Additional yeast one-hybrid studies performed with Arabidopsis transcription factors revealed binding of the promoter fragments by proteins involved in the ethylene signal transduction pathway, contributing to the idea that these SlTCP genes are involved in the ripening process. Yeast two-hybrid data shows that SlTCP proteins can form homo and heterodimers, suggesting that they act together in order to form functional protein complexes and together regulate developmental processes in tomato.
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