Staff Publications

Staff Publications

  • external user (warningwarning)
  • Log in as
  • language uk
  • About

    '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.

    We have a manual that explains all the features 

    Records 1 - 20 / 290

    • help
    • print

      Print search results

    • export
      A maximum of 250 titles can be exported. Please, refine your queryYou can also select and export up to 30 titles via your marked list.
    Check title to add to marked list
    Monitoren, niet berekenen
    Hermans, Tia - \ 2020
    Quantifying solvent action in oil paint using portable laser speckle imaging
    Baij, Lambert ; Buijs, Jesse ; Hermans, Joen J. ; Raven, Laura ; Iedema, Piet D. ; Keune, Katrien ; Sprakel, Joris - \ 2020
    Scientific Reports 10 (2020)1. - ISSN 2045-2322

    The exposure of oil paintings to organic solvents for varnish removal or to water for the removal of surface dirt can affect the chemical and physical properties of oil paint in an undesired way. Solvents can temporarily plasticise and swell the polymerised oil paint binding medium, enhancing both the thermal mobility and mechanical displacement of pigments embedded in this film. The enhancement of these microscopic motions can affect both the chemical and physical stability of the object as a whole. In order to minimise solvent exposure during cleaning, an analytical method that can quantitatively measure the microscopic motions induced by solvent uptake, is required first. In this study, we use Fourier Transform Laser Speckle Imaging (FT-LSI) and a newly developed portable FT-LSI setup as highly resolved motion detection instruments. We employ FT-LSI to probe pigment motion, with high spatiotemporal resolution, as a proxy for the destabilising effects of cleaning solvents. In this way, we can study solvent diffusion and evaporation rates and the total solvent retention time. In addition, qualitative spatial information on the spreading and homogeneity of the applied solvent is obtained. We study mobility in paint films caused by air humidity, spreading of solvents as a result of several cleaning methods and the protective capabilities of varnish. Our results show that FT-LSI is a powerful technique for the study of solvent penetration during oil paint cleaning and has a high potential for future use in the conservation studio.

    Tackling the nitrogen problem in five stages
    Hermans, Tia ; Dijkstra, Jan ; Smits, Nina ; Groenestein, Karin ; Ogink, Nico ; Huijsmans, Jan ; Velthof, Gerard ; Jongschaap, Raymond ; Geerdink, Peter ; Munniks, Sandra ; Jongeneel, Roel ; Ravesloot, Marc - \ 2020

    interview met Tia Hermans en Jan Dijstra en Nina Smits

    Deciphering interwoven drivers of environment-related migration – A multisite case study from the Ethiopian highlands
    Groth, Juliane ; Ide, Tobias ; Sakdapolrak, Patrick ; Kassa, Endeshaw ; Hermans, Kathleen - \ 2020
    Global environmental change : human and policy dimensions 63 (2020). - ISSN 0959-3780
    Adaptation - Africa - Climate change - Environment-related migration - Qualitative comparative analysis (QCA)

    Global environmental change is increasing livelihood pressure for many communities, and agricultural households in the Global South are particularly vulnerable. Extant research has debated whether and to what degree this amplifies migration flows while also acknowledging that migration can be an adaptive strategy. However, little is known about which contextual factors are most relevant and how they interact in shaping environment-related migration. We shed light on this issue by conducting an in-depth qualitative, yet multisite and medium-N study of farming households in the northern Ethiopian highlands. We utilized qualitative comparative analysis (QCA) – a novel approach in the research field – to overcome the existing methodological challenges. We found that the migration experience within the household in combination with either the usage of the longer summer rainy season (Kiremt) or non-farm in situ diversification are sufficient causes for migration. Non-farm income activities and favorable environmental conditions during the Kiremt season increases economic household resources and as such migration ability. However, only together with migrant networks, which can reduce the costs and risks of migration and shape migration aspirations, can these drivers explain why households engage in migration. Our findings reveal that capabilities and networks, rather than commonly cited push factors, are far more important drivers of environment-related migration at the household level. Additionally, we illustrate that while migration is an important adaptation strategy, it cannot be adopted equally among households and as a result often reinforces existing inequalities.

    Nieuwe aanpak voor het stikstofprobleem
    Hermans, Tia - \ 2020
    Nutrient solutions for Arabidopsis thaliana : A study on nutrient solution composition in hydroponics systems
    Delden, Sander H. Van; Nazarideljou, Mohammad Javad ; Marcelis, Leo F.M. - \ 2020
    Plant Methods 16 (2020)1. - ISSN 1746-4811
    Electrical conductivity (EC) - Growth - Hydroponic system - Nutrient solution - Salt (NaCl) response

    Background: There is little information on the effect of nutrient solutions composition on Arabidopsis growth. Therefore, we compared growth performance of Arabidopsis thaliana (Col-0) grown on the most commonly used nutrient solutions in deep water culture: Hoagland and Arnon, Murashige and Skoog, Tocquin, Hermans, and Conn. In addition to these nutrient solution composition experiments, we established Arabidopsis growth response curves for nutrient solution concentration and salt stress (NaCl). Results: Arabidopsis rosette fresh and dry weight showed an approximate linear decline with NaCl dose in deep water culture, i.e. 9% reduction relative to control per unit of electrical conductivity (EC in dS m-1, for scale comprehension 1 dS m-1 equals ~ 10 mM NaCl). The Tocquin, ½Hoagland and Conn nutrient solutions had equal and optimal growth performance. Optimal nutrient solution concentration for Tocquin and Hoagland was 0.8 to 0.9 dS m-1. Close to the EC of ½Hoagland (1.1 dS m-1), which is frequently used in Arabidopsis research. Conn solution showed optimal growth at much higher EC (2 dS m-1) indicating that it is a balanced nutrient solution that matches the needs of Arabidopsis. Full Murashige and Skoog solution (5.9 dS m-1) was lethal and diluted solutions (EC of 1.6 and 1.1 dS m-1) caused stress symptoms and severe growth retardation at later developmental stages. Conclusions: Arabidopsis thaliana (Col-0) plants grown in deep water culture showed a sixfold growth difference when commonly used nutrient solutions were compared. Murashige and Skoog solution should not be used as nutrient solution in deep water culture. Conn, Tocquin and ½Hoagland are balanced nutrient solutions which result in optimal Arabidopsis growth in hydroponic systems.

    Integrative policy development for healthier people and ecosystems : A European case analysis
    White, Piran C.L. ; Guégan, Jean François ; Keune, Hans ; Bell, Sian De; Geijzendorffer, Ilse R. ; Hermans, Tia ; Prieur-Richard, Anne Hélène ; Iroegbu, Chinny ; Stone, Dave ; Vanwambeke, Sophie ; Vries, Sjerp de; Ford, Adriana ; Graham, Hilary - \ 2020
    Area (2020). - ISSN 0004-0894
    biodiversity - cross-sectoral policy - ecosystem services - environment - evidence - public health

    There is growing evidence of the inter-relationships between ecosystems and public health. This creates opportunities for the development of cross-sectoral policies and interventions that provide dual benefits to public health and to the natural environment. These benefits are increasingly articulated in strategy documents at national and regional level, yet implementation of integrative policies on the ground remains limited and fragmented. Here, we use a workshop approach to identify some features of this evidence–implementation gap based on policy and practice within a number of western European countries. The driving forces behind some recent moves towards more integrative policy development and implementation show important differences between countries, reflecting the non-linear and complex nature of the policy-making process. We use these case studies to illustrate some of the key barriers to greater integrative policy development identified in the policy analysis literature. Specific barriers we identify include: institutional barriers; differing time perspectives in public health and ecosystem management; contrasting historical development of public health and natural environment disciplinary policy agendas; an incomplete evidence base relating investment in the natural environment to benefits for public health; a lack of appropriate outcome measures including benefit–cost trade-offs; and finally a lack of integrative policy frameworks across the health and natural environment sectors. We also identify opportunities for greater policy integration and examples of good practice from different countries. However, we note there is no single mechanism that will deliver integrative policy for healthier people and ecosystems in all countries and situations. National governments, national public agencies, local governments, research institutions, and professional bodies all share a responsibility to identify and seize opportunities for influencing policy change, whether incremental or abrupt, to ensure that ecosystems and the health of society are managed so that the interests of future generations, as well as present generations, can be protected.

    Nature-Inclusive Design options : infographic
    Hermans, A. ; Bos, O.G. ; Prusina, I. - \ 2020
    Witteveen+Bos - 1 p.
    Natuurinclusieve ontwerpopties : infographic
    Hermans, A. ; Bos, O.G. ; Prusina, I. - \ 2020
    Witteveen+Bos - 1 p.
    Nature-Inclusive Design: a catalogue for offshore wind infrastructure : Technical report
    Hermans, A. ; Bos, O.G. ; Prusina, I. - \ 2020
    Den Haag : Witteveen+Bos (Technical report 114266/20-004.274) - 50 p.
    soortenrijkdom - biodiversiteit - mariene ecologie - Noordzee - Nederland - Species - Species richness - Biodiversity - Marine ecology - North Sea - Netherlands - Offshore windergie - Natuurherstel - Nature restoration - Platte oester - Flat oysters
    Offshore wind farms in the Dutch North Sea must make demonstrable efforts to stimulate native nature within the wind farm. For example, suitable scour protection or fish hotels can be placed around wind turbines that serve as nursery areas or offer shelter. Also flat oysters can be placed, which can form reefs and attract great biodiversity. Commissioned by the Ministry of Agriculture, Nature and Food Quality, Witteveen+Bos and Wageningen Marine Research have produced a catalog of such Nature Inclusive Design options. The catalog shows the target species for which the option is suitable, the expected construction costs, and where the materials can be purchased.
    How does nature contribute to human mobility? A conceptual framework and qualitative analysis
    Wiederkehr, Charlotte ; Schröter, Matthias ; Adams, Helen ; Seppelt, Ralf ; Hermans, Kathleen - \ 2019
    Ecology and Society 24 (2019)4. - ISSN 1708-3087
    Bangladesh - Ethiopia - Immobility - Mobility - Nature’s contributions to people - Place attachment

    Different types of mobility are known as longstanding strategies used by humans to deal with environmental pressure. Immobility is relevant in this context as population groups may be at considerable risk but lacking the capacity or willingness to move. Despite significant advances in this research field, grasping especially the subjective dimension of people’s migration decision remains challenging. Moreover, the conceptualization of cultural factors in this context has received rather marginal attention thus far. In light of this, we propose a framework that integrates the novel concept of nature’s contributions to people (NCP) with migration theory, in particular the triad of migration need, ability, and aspiration. NCP goes beyond the popular notion of ecosystem services by conceiving nature-society relations in a more inclusive way with culture being a key element of these. Combined with migration need, ability, and aspiration, we argue that this approach offers a valuable nuanced perspective on nature-mobility interactions, including cultural aspects of natural resource use and varying degrees of agency related to mobility decision making. We apply the framework to two archetypal climate-related migration situations, southwestern coastal Bangladesh and the northern Ethiopian highlands, to delineate the diverse mechanisms through which environmental change shapes population movement in highly resource-dependent livelihoods. We show that based on the analyzed case studies most links can be drawn between material and regulating NCP and migration need, and that nonenvironmental factors play a crucial role in mediating nature’s contributions to human mobility. More knowledge is needed though in particular on the influence of nonmaterial NCP on mobility decision making and on migration aspirations in general to better account for important cultural factors. We formulate a number of hypotheses and questions relevant for guiding future research that can inform policy interventions.

    Plantbenefits : intervention study on the effects of office plants on indoor climate, the appreciation of the environment by employees, and their functioning and wellbeing
    Vries, S. de; Hermans, C.M.L. ; Duijn, Bert van; Oppedijk, Berry - \ 2019
    In: International Conference on Environmental Psychology 2019. - Plymouth : ICEP
    A field experiment with a controlled pretest-posttest design was conducted in three organizations. In each organization, two offices were selected. One month after the pretest, plants were introduced in one of the offices. The plants are aimed at increasing the air humidity in wintertime by 15%-points. After three months, a posttest was conducted. Temperature and air humidity were monitored for one year. In total, 75 employees participated during both pre- and posttest. Analyses of variance were conducted, with Time as within-subjects factor and Condition and Organization as between-subjects factors. Positive effects of the plants were observed for the visual appearance of the office, having positive feelings and self-rated functioning. A negative effect was observed for the need for recovery after a working day. No effect was observed for other measures, o.a. thermal comfort, ability to concentrate, stress level, social climate. The most striking result was a logistic regression for having reported sick during the previous three months (control = reference), adjusting for organization and sickness reporting on the pretest, showing a rather substantial effect of Condition: OR = 0.22 (0.05-0.93). At the moment, the study is being replicated at more locations, with a larger number of participants.
    Toll-Like Receptor-dependent immunomodulatory activity of Pycnogenol
    Verlaet, Annelies A.J. ; Bolt, Nieke van der; Meijer, Ben ; Breynaert, Annelies ; Naessens, Tania ; Konstanti, Prokopis ; Smidt, Hauke ; Hermans, Nina ; Savelkoul, Huub ; Teodorowicz, Gosia - \ 2019
    Wageningen University
    PRJEB29793 - ERP112142 - metagenome
    Background: Pycnogenol® (PYC), a patented herbal extract of French maritime pine bark, consists of a complex mixture of bioflavonoids. The main constituents of PYC are procyanidins; biopolymers consisting of units of catechin (CAT) and epicatechin. PYC is shown to exert immunomodulatory properties, nevertheless its underlying mechanisms are not yet fully elucidated. Methods: In this study, the effect of PYC and its constituent CAT on membrane Toll like receptor (TLR) activity was examined using stably transfected Human Embryonic Kidney cells. The Human monocytic leukaemia cell line THP-1 was used to examine the effect of PYC and CAT on pro-inflammatory cytokine release.Findings: We showed that non-metabolised PYC acts as agonist of TLR1/2, TLR2/6 and a partial agonist of TLR5, which resulted in the induction of pro-inflammatory cytokine secretion from THP-1 macrophages as well as activation of Nf-κB transcription factor. This effect was altered due to gastrointestinal metabolism, which revealed immuno-suppressive potential against TLR 1/2 and TLR 2/6 of the retentate fraction compared to the control sample. Moreover, the dialysed fraction did not show potential to induce pro-inflammatory cytokine secretion by THP-1 macrophages but the capacity to induce anti-inflammatory IL-10. Moreover, we showed that PYC on its own does not activate TLR4 but the formation of complexes with lipopolysaccharides (LPS) is required to stimulate the TLR4 receptor. We found that PYC and PYC-LPS complexes to the same extend dose-dependently increase pro-inflammatory cytokine levels (IL-8, IL-1β and TNF) and upregulate phosphorylation of the transcription factor NF-ĸB. No effects for CAT were observed on TLR activation and pro-inflammatory cytokine production levels. Conclusions: Our study stresses the importance of metabolism for biological activity of PYC compounds. Moreover our results suggest that bot non-metabolised as well as metabolised PYC acts via TLR 1/2 and TLR 2/6 next to TLR4.
    Effects of eating with an augmented fork with vibrotactile feedback on eating rate and body weight: a randomized controlled trial
    Hermsen, Sander ; Mars, Monica ; Higgs, Suzanne ; Frost, Jeana H. ; Hermans, Roel C.J. - \ 2019
    International journal of behavioral nutrition and physical activity 16 (2019)1. - ISSN 1479-5868 - 1 p.
    Eating rate - Feedback - Randomized controlled trial - Sensory - Weight loss

    BACKGROUND: Eating rate is a basic determinant of appetite regulation: people who eat more slowly feel sated earlier and eat less. A high eating rate contributes to overeating and potentially to weight gain. Previous studies showed that an augmented fork that delivers real-time feedback on eating rate is a potentially effective intervention to decrease eating rate in naturalistic settings. This study assessed the impact of using the augmented fork during a 15-week period on eating rate and body weight. METHODS: In a parallel randomized controlled trial, 141 participants with overweight (age: 49.2 ± 12.3 y; BMI: 31.5 ± 4.48 kg/m2) were randomized to intervention groups (VFC, n = 51 or VFC+, n = 44) or control group (NFC, n = 46). First, we measured bite rate and success ratio on five consecutive days with the augmented fork without feedback (T1). The intervention groups (VFC, VFC+) then used the same fork, but now received vibrotactile feedback when they ate more than one bite per 10 s. Participants in VFC+ had additional access to a web portal with visual feedback. In the control group (NFC), participants ate with the fork without either feedback. The intervention period lasted four weeks, followed by a week of measurements only (T2) and another measurement week after eight weeks (T3). Body weight was assessed at T1, T2, and T3. RESULTS: Participants in VFC and VFC+ had a lower bite rate (p < .01) and higher success ratio (p < .0001) than those in NFC at T2. This effect persisted at T3. In both intervention groups participants lost more weight than those in the control group at T2 (p < .02), with no rebound at T3. CONCLUSIONS: The findings of this study indicate that an augmented fork with vibrotactile feedback is a viable tool to reduce eating rate in naturalistic settings. Further investigation may confirm that the augmented fork could support long-term weight loss strategies. TRIAL REGISTRATION: The research reported in this manuscript was registered on 4 November 2015 in the Netherlands Trial Register with number NL5432 ( https://www.trialregister.nl/trial/5432 ).

    Op naar precisielandbouw 2.0 : eindrapport PPS PL2.0 2015-2019 topsectorproject AF-14275
    Kempenaar, Corné ; Dijk, Chris van; Hermans, Geert ; Steele-Dun, Susan ; Sande, Corné van de; Verschoore, Jeroen ; Wal, Tamme van der; Roerink, Gerbert ; Visser, Juriaan ; Kamp, Jan ; Blok, Pieter ; Polder, Gerrit ; Wolf, Jan van de; Jalink, Henk ; Bulle, Annette ; Meurs, Bert ; Michielsen, Jean-Marie ; Zande, Jan van de; Hoving, Idse ; Riel, Johan van; Holshof, Gertjan ; Boheemen, Koen van; Evert, Frits van; Riemens, Marleen ; Keizer, Paul ; Schnabel, Sabine ; Egmond, Fenny van; Walvoort, Dennis ; Janssen, Henk ; Riviėre, Inge La; Kocks, Corné ; Pot, Alfred - \ 2019
    Lelystad : Stichting Wageningen Research, Wageningen University & Research (Rapport WPR 921) - 138
    De publiek private samenwerking (PPS) ‘Op naar precisielandbouw 2.0’ (PL2.0) is een R&D project van de topsector AgriFood. Het project is gestart in 2015 met doorlooptijd van 4 jaar. Voor u ligt het eindrapport. In deze PPS werkten ruim 20 private bedrijven en organisaties, publieke kennisinstellingen en overheden samen aan strategische onderwerpen binnen precisielandbouw. Het project omvatte 13 deelprojecten verdeeld over vijf specifieke R&D thema’s, te weten slim satellietbeeldengebruik, sensorontwikkeling (ziektedetectie), slimme integratie van technologieën in toepassingen, perceelkarakteristieken voor schatten van opbrengstpotentie en ondersteunende ICT, en een generiek thema communicatie en kennisverspreiding.Met betrekking tot het thema satellietbeeldengebruik is uitgezocht hoe optische satellietbeelden in combinatie met radarbeelden of beelden verkregen via drone-camera’s beter gebruikt kunnen worden om de variatie en status van de bovengrondse hoeveelheid biomassa van gewassen in kaart te brengen en opbrengsten te voorspellen. Op het gebied van ziektedetectie is door middel van sensor fusion en artificial intelligence de detectie van virus- en bacterieziekten in aardappelplanten verbeterd. En werd een prototype sensorsysteem voor veldonderzoek ontwikkeld. Door slimme integratie van data, adviesmodellen en mechanisatie zijn er enkele variabel-doseertoepassingen ontwikkeld en gevalideerd. Het gaat hier om variabel doseren van Stikstof en herbiciden binnen teelten d.m.v. taakkaarten. In het verlengde hiervan is ook een ontwerp geleverd en als prototype gevalideerd voor een innovatieve beddenspuit in bloembollenteelt. Op grond van perceelkarakteristieken en ondersteunende ICT zijn inzichten en tools voor het inschatten van opbrengst(potentie) geleverd en wordt een doorkijk gegeven naar software voor verbeterde rijpadenplanning en perceelinformatie. De inzet op communicatie en kennisdeling heeft ca. 100 publicaties en presentaties in 4 jaar tijd opgeleverd. Voor meer details over resultaten wordt naar de rapportage met samenvatting per deelproject verwezen in de hoofdstukken 2 tot en met 7.Het grote succes van PL2.0 ligt vooral bij ruime aandacht voor integratie van componenten van precisielandbouwtoepassingen en de doorstroming daarvan naar de praktijk en onderwijs.Geconcludeerd mag worden dat PL2.0 een bijdrage leverde aan gewasmonitoringtoepassingen en diverse variabel-doseertoepassingen (variable rate applications, VRA). Die VRA-toepassingen zien we nu op de agenda in het in 2018 gestarte precisielandbouw-adoptie project ‘Nationale Proeftuin Precisielandbouw’ (NPPL). Meerdere bedrijven passen taakkaarten variabel doseren op een resolutie van 30-50 m2 op praktijkschaal toe en besparen zo’n 20 -30% op gewasbeschermingsmiddelen met behoud van goede werking. De basis hiervoor is een bodem- of gewaskaart die de relevante variatie binnen de bodem of gewas in kaart brengt. Ook zijn er via PL2.0 mooie resultaten met optimalisatie van plantdichtheid en vermindering van meststoffengebruik via deze kaarten. Doorstroming van kennis naar het groene onderwijs werd gerealiseerd via PL2.0 en een versterkend WURKS-traject. Negen lesmodules over gebruik software en inzet taakkaarten in precisielandbouw werden opgeleverd. Precisielandbouw is geen doel op zich, maar een manier om de duurzaamheid van landbouw te vergroten. Met PL2.0 toepassingen kan meer met minder en beter geproduceerd worden. De trend van precisielandbouw c.q. data-gedreven landbouw of smart farming, zal zich alleen maar doorzetten. Er zal gewerkt gaan worden met meer en hoog-resolutie data, complexere adviesmodellen en meer robotisering. Daarmee zullen de doelen van kringlooplandbouw beter en sneller gerealiseerd kunnen worden.
    Supplementation with Akkermansia muciniphila in overweight and obese human volunteers: a proof-of-concept exploratory study
    Depommier, Clara ; Everard, Amandine ; Druart, Céline ; Plovier, Hubert ; Hul, Matthias Van; Vieira-Silva, Sara ; Falony, Gwen ; Raes, Jeroen ; Maiter, Dominique ; Delzenne, Nathalie M. ; Barsy, Marie de; Loumaye, Audrey ; Hermans, Michel P. ; Thissen, Jean Paul ; Vos, Willem M. de; Cani, Patrice D. - \ 2019
    Nature Medicine 25 (2019)7. - ISSN 1078-8956 - p. 1096 - 1103.

    Metabolic syndrome is characterized by a constellation of comorbidities that predispose individuals to an increased risk of developing cardiovascular pathologies as well as type 2 diabetes mellitus1. The gut microbiota is a new key contributor involved in the onset of obesity-related disorders2. In humans, studies have provided evidence for a negative correlation between Akkermansia muciniphila abundance and overweight, obesity, untreated type 2 diabetes mellitus or hypertension3–8. Since the administration of A. muciniphila has never been investigated in humans, we conducted a randomized, double-blind, placebo-controlled pilot study in overweight/obese insulin-resistant volunteers; 40 were enrolled and 32 completed the trial. The primary end points were safety, tolerability and metabolic parameters (that is, insulin resistance, circulating lipids, visceral adiposity and body mass). Secondary outcomes were gut barrier function (that is, plasma lipopolysaccharides) and gut microbiota composition. In this single-center study, we demonstrated that daily oral supplementation of 1010A. muciniphila bacteria either live or pasteurized for three months was safe and well tolerated. Compared to placebo, pasteurized A. muciniphila improved insulin sensitivity (+28.62 ± 7.02%, P = 0.002), and reduced insulinemia (−34.08 ± 7.12%, P = 0.006) and plasma total cholesterol (−8.68 ± 2.38%, P = 0.02). Pasteurized A. muciniphila supplementation slightly decreased body weight (−2.27 ± 0.92 kg, P = 0.091) compared to the placebo group, and fat mass (−1.37 ± 0.82 kg, P = 0.092) and hip circumference (−2.63 ± 1.14 cm, P = 0.091) compared to baseline. After three months of supplementation, A. muciniphila reduced the levels of the relevant blood markers for liver dysfunction and inflammation while the overall gut microbiome structure was unaffected. In conclusion, this proof-of-concept study (clinical trial no. NCT02637115) shows that the intervention was safe and well tolerated and that supplementation with A. muciniphila improves several metabolic parameters.

    Planten voor een prima binnenklimaat : Industriële spoor
    Hermans, Tia ; Vries, Sjerp de; Jeurissen, Leonn ; Kraan, Jolanda ; Oppedijk, Berry ; Duijn, Bert van - \ 2019
    Wageningen : Wageningen Environmental Research (Wageningen Environmental Research rapport 2952) - 167
    A conceptual model was developed, describing the short-term, medium and long-term effects of plants on the indoor climate and the health and well-being of people. The model was tested by means of intervention research at three companies and eight homes for the elderly. The effect of plants on the physical indoor climate was measured with sensors, the effect on the health and well-being of employees with questionnaires. In principle, a ‘Before After Control Impact’ approach was used at the locations. A control room and an intervention room were selected for each location. After a pre-measurement, plants were placed in the intervention room and up to three post-measurements were conducted. At the companies, significant effects were found on relative humidity (up), attractiveness of the workplace (more attractive), state of mind (more positive), satisfaction with own functioning (higher) and sickness absence reporting (less). The need for recovery after a working day showed a reversed effect (rising). No significant effects were found for the other variables in the model. Similar effects were not observed in the homes for the elderly. Possible reasons for the latter are: the small number of employees working in the same room (i.e., living room for clients), a low willingness amongst these employees to participate in the study (high work pressure), a high mobility amongst employees and working in both the intervention and the control room.
    Bioturbation of Ag2S-NPs in soil columns by earthworms
    Baccaro, Marta ; Harrison, Samuel ; Berg, Hans van den; Sloot, Laura ; Hermans, Davy ; Cornelis, Geert ; Gestel, Cornelis A.M. van; Brink, Nico W. van den - \ 2019
    Environmental Pollution 252 (2019). - ISSN 0269-7491 - p. 155 - 162.
    Bioturbation - Earthworms - Nanoparticles - Soil - Transport

    Sewage sludge contains Ag2S-NPs causing NP exposure of soil fauna when sludge is applied as soil amendment. Earthworm bioturbation is an important process affecting many soil functions. Bioturbation may be affected by the presence of Ag2S-NPs, but the earthworm activity itself may also influence the displacement of these NPs that otherwise show little transport in the soil. The aim of this study was to determine effects of Ag2S-NPs on earthworm bioturbation and effect of this bioturbation on the vertical distribution of Ag2S-NPs. Columns (12 cm) of a sandy loamy soil with and without Lumbricus rubellus were prepared with and without 10 mg Ag kg−1, applied as Ag2S-NPs in the top 2 cm of the soil, while artificial rainwater was applied at ∼1.2 mm day−1. The soil columns were sampled at three depths weekly for 28 days and leachate collected from the bottom. Total Ag measurements showed more displacement of Ag to deeper soil layers in the columns with earthworms. The application of rain only did not significantly affect Ag transport in the soil. No Ag was detected in column leachates. X-ray tomography showed that changes in macro porosity and pore size distribution as a result of bioturbation were not different between columns with and without Ag2S-NPs. Earthworm activity was therefore not affected by Ag2S-NPs at the used exposure concentration. Ag concentrations along the columns and the earthworm density allowed the calculation of the bioturbation rate. The effect on the Ag transport in the soil shows that earthworm burrowing activity is a relevant process that must be taken into account when studying the fate of nanoparticles in soils. Earthworm bioturbation plays a more important role than rainfall in the vertical transport of Ag2S-NPs in soil.

    Oxidative stress and immune aberrancies in attention-deficit/hyperactivity disorder (ADHD): a case–control comparison
    Verlaet, Annelies A.J. ; Breynaert, Annelies ; Ceulemans, Berten ; Bruyne, Tess De; Fransen, Erik ; Pieters, Luc ; Savelkoul, Huub F.J. ; Hermans, Nina - \ 2019
    European Child & Adolescent Psychiatry 28 (2019)5. - ISSN 1018-8827 - p. 719 - 729.
    ADHD - Antioxidants - Diet - Immunity - Oxidative stress

    The objective of this study is to compare oxidative stress and immune biomarkers between attention-deficit/hyperactivity disorder (ADHD) patients and controls without ADHD. A case–control comparison between 57 paediatric (6–12 years) untreated ADHD patients from the Antwerp University Hospital and 69 controls without ADHD from random schools in Flanders, Belgium, was conducted. Erythrocyte glutathione (GSH) and plasma lipid-soluble antioxidants (retinol, α-tocopherol, γ-tocopherol, retinyl palmitate, β-carotene, and co-enzyme Q10) were determined by HPLC with electrochemical detection, plasma malondialdehyde (MDA) by HPLC with fluorescence detection, plasma cytokines (interleukin (IL)-1β, IL-5, IL-6, IL-8, IL-10, tumour necrosis factor (TNF) and interferon (INF)-γ) and immunoglobulins (IgE, IgG and IgM) by flow cytometry and urinary 8-hydroxy-2′deoxyguanosine (8-OHdG) levels by ELISA assay. Dietary habits were determined by a food frequency questionnaire. Plasma MDA levels were on average 0.031 µM higher in patients than in controls (p < 0.05), and a trend for higher urinary 8-OHdG was observed. Erythrocyte GSH and plasma retinyl palmitate levels, as well as IgG and IgE levels, were higher in patients than in controls as well (on average 93.707 µg/ml, 0.006 µg/ml, 301.555 µg/ml and 125.004 µg/ml, resp., p < 0.05). Finally, a trend for lower plasma IL-5 levels was observed. After Bonferroni correction for multiple testing, the difference in GSH levels remained statistically significant (nominally significant for retinyl palmitate), while significance was lost for MDA, IgG and IgE levels. Dietary habits do not appear to cause the observed differences. These results point at the potential involvement of slight oxidative stress and immune disturbances in ADHD.

    Binnengroen méér dan mooi alleen! : perspectief voor Human Resource en Facilitair Management
    Hermans, C.M.L. - \ 2019
    Check title to add to marked list
    << previous | next >>

    Show 20 50 100 records per page

     
    Please log in to use this service. Login as Wageningen University & Research user or guest user in upper right hand corner of this page.