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Aanpak van vogelmijt bij pluimvee
No full textTo manage Red Poultry Mite (RPM) in laying hen farms, a large project has bene carried out. With 20 commercial test farms the total concept IPM (Integrated Pest Management) has been tested and optimized. The RPM populations on these farms as well as on 10 control farms have been monitored. Monitoring has been optimized and an advice has been formed how this can best be done. The economic consequences of RPM are listed. For the use of chemicals against PRM an overview has been made of the allowed chemicals and under what legislation they are allowed. Also for new chemicals the possibilities are given for registration or obtaining allowance to use
Classification of the European marsh vegetation (Phragmito-Magnocaricetea) to the association level
No full textAims: To create a comprehensive, consistent and unequivocal phytosociological classification of European marsh vegetation of the class Phragmito-Magnocaricetea. Location: Europe. Methods: We applied the Cocktail method to a European data set of 249,800 vegetation plots. We identified the main purposes and attributes on which to base the classification, defined assignment rules for vegetation plots, and prepared formal definitions for all the associations, alliances and orders of the class Phragmito-Magnocaricetea using formal logic. Each formula consists of the combination of “functional species groups”, cover values of individual species, and in the case of high-rank syntaxa also of “discriminating species groups” created using the Group Improvement (GRIMP) method. Results: The European Phragmito-Magnocaricetea vegetation was classified into 92 associations grouped in 11 alliances and six orders. New syntaxa (previously invalidly published according to the International Code of Phytosociological Nomenclature) were introduced: Bolboschoeno maritimi-Schoenoplection tabernaemontani, Glycerio maximae-Sietum latifolii, Glycerio notatae-Veronicetum beccabungae, Schoenoplectetum corymbosi and Thelypterido palustris-Caricetum elongatae. Based on a critical revision, some other syntaxa were rejected or excluded from the class Phragmito-Magnocaricetea. Conclusions: This work provides the first consistent classification of the class Phragmito-Magnocaricetea at the European scale, which is an important tool for nature conservation. Our classification largely respects previously existing concepts of syntaxa, but it also proposes modifications to the recently published EuroVegChecklist. This work also provides a protocol that can be used for extending the current classification to new syntaxa and geographical regions.</p
Microbiome-derived carnitine mimics as previously unknown mediators of gut-brain axis communication
No full textAlterations to the gut microbiome are associated with various neurological diseases, yet evidence of causality and identity of microbiome-derived compounds that mediate gut-brain axis interaction remain elusive. Here, we identify two previously unknown bacterial metabolites 3-methyl-4-(trimethylammonio)butanoate and 4-(trimethylammonio)pentanoate, structural analogs of carnitine that are present in both gut and brain of specific pathogen-free mice but absent in germ-free mice. We demonstrate that these compounds are produced by anaerobic commensal bacteria from the family Lachnospiraceae (Clostridiales) family, colocalize with carnitine in brain white matter, and inhibit carnitine-mediated fatty acid oxidation in a murine cell culture model of central nervous system white matter. This is the first description of direct molecular inter-kingdom exchange between gut prokaryotes and mammalian brain cells, leading to inhibition of brain cell function.</p
The ex/inclusion paradox in heritage management : the Mobarak mosque in The Hague
No full textPurpose: In the field of critical heritage studies, it has often been argued that a more inclusive and participatory heritage management approach neutralises differences and can contribute to a more contemporary, plural, democratic and inclusive notion of heritage. Yet, the needs and aspirations of those assumed being excluded from heritage making are not always taken into account, because the analysis and critique often focussed on the dominant heritage discourses, organisations and institutions. This paper conceptualises heritage from below and explores and reconceptualises how subdominant notions of heritage relate to dominant, institutionalised conceptualisations of heritage. Design/methodology/approach: Based on a case study of the Mobarak mosque in The Hague, the authors present the multiplicity of subdominant conceptualisations of heritage, the ways heritage is (expected to be) recognised and represented by the community and the complexity of issues of social inclusion/exclusion. Findings: The authors conclude that inclusive and/or participatory heritage management practices are inclusive in name only when the needs and aspirations of those seemingly being “excluded” are not fully understood and taken into account. Originality/value: A binary heritage/non-heritage framework, the authors argue, is limited to understand matter that matters. Also the authors find that the assumption that there is a growing desire among local community groups to include their histories and related materialities as heritage in the dominant heritage discourse should be challenged.</p
Evaluation of equine rectal inoculum as representative of the microbial activities within the horse hindgut using a fully automated in vitro gas production technique system
No full textThe in vitro gas production technique (IVGPT) has been a valuable tool in ruminant nutrition research for decades and has more recently been used in horse nutrition studies to investigate fermentation activities of the equine hindgut though primarily using feces as inoculum. This study was conducted to evaluate the use of equine rectal content in the IVGPT system as a viable inoculum that can be considered representative of the activities throughout the equine hindgut. Additionally, the study was conducted to measure the effects on fermentation kinetics and end-product production using inoculum from horses fed supplemental levels of coated sodium butyrate in an IVGPT system. Eight warmblood horses were fed a diet consisting of haylage (1% DM intake based on ideal body weight [BW]) and a mash concentrate formulated to provide 2.5 g nonstructural carbohydrate (NSC)/kg BW per meal. The diet was intended to create a NSC challenge to the microbial populations of the hindgut. The horses were randomly assigned to treatment or control group and after a 1-wk diet-adaptation period, the treatment group received 0.4 g/kg BW per day of a coated sodium butyrate supplement, while the control group received a placebo (coating only). After a 3-wk treatment period, the animals were sacrificed and digesta from the cecum, left ventral colon, right dorsal colon, and the rectum were collected within 30 min postmortem and used as inocula for the IVGPT trial. Haylage and concentrates fed to the test animals were also used as substrates in vitro. Sodium butyrate supplementation was not significant for gas production parameters or VFA measured suggesting no effect of sodium butyrate supplementation on the extent or kinetics of gas production or microbial end-product production (P ≥ 0.073). Differences in inocula were significant for organic matter corrected cumulative gas production (P = 0.0001), asymptotic gas production of the second phase (A2) (P < 0.0001); and maximal rate of OM degradation of the second phase (Rmax2) (P = 0.002). Inocula had a significant effect on total VFA (P = 0.0002), butyrate (Bu) (P = 0.015), branched chain fatty acids (P < 0.0001), pH (P < 0.0001), and ammonia (NH3) (P = 0.0024). In conclusion, based on observed results from this study, total tract digestibility may be overestimated if using rectal content inoculum to evaluate forage-based feeds in an IVGPT system.</p
Land use and land cover scenarios : An interdisciplinary approach integrating local conditions and the global shared socioeconomic pathways
No full textLand Use and Land Cover (LULC) changes have profound impacts on the functioning of (agro)ecosystems and have potential to mitigate global climate change. However, we still lack interdisciplinary methods to project future LULC scenarios at spatial scales that are relevant for local decision making and future environmental assessments. Here we apply an interdisciplinary approach to develop spatially explicit projections of LULC at a resolution of 30 × 30 m informed by historic relationships between LULC and their key drivers, within the context of the four qualitative scenarios of global shared socioeconomic pathways. We apply this methodology to a case study in the Zona da Mata, Brazil, which has a history of major LULC changes. The analysis of LULC changes from 1986 to 2015 indicates that pasture area decreased from 76 to 58 % of total area, while forest areas increased from 18 to 24 %, and coffee from 3 to 11 %. Environmental protection legislation, rural credit for smallholder farmers, and demand for agricultural and raw products were identified as main drivers of LULC changes. Projected LULC for 2045 strongly depends on the global socioeconomic pathway scenarios, and forest and coffee areas may increase substantially under strong government measures in the environmentally conscious Green Road scenario or decrease in the high consumption Rocky Road scenario. Our study shows that under the set of drivers during the past three decades reforestation can go hand in hand with increase of agricultural production, but that major and contrasting changes in LULC can be expected depending on the socioeconomic pathway that will be followed in the future. To guide this process, LULC scenarios at the local scale can inform the planning of local and regional development and forest conservation.</p
Microbial lifestyle engineering
Get PDFUsing Pseudomonas putida KT2440 as a proof-of-concept organism, this thesis was aimed at microbial lifestyle engineering for industrial applications. In this thesis, a structured approach was applied by first determining what microbial improvements industry is looking for by conducting a series of interviews with both industry and academia. Besides pinpointing the fields of interest from an industrial perspective, the interviews also clarified the limitations of the actual implementation of novel or (synthetically) adapted strains developed. Strain safety being at the top of their list, we first checked the claimed GRAS safety level of P. putida KT2440. A major obstacle for the breakthrough of P. putida KT2440 to be widely used as a biotechnological host is its obligate aerobic metabolism. In silico-directed strain improvement were initiated by the adaptation of strict aerobic P. putida KT2440 to micro-oxic and anoxic conditions. Adaptation to micro-oxic levels was done by first creating a design for a recombinant strain capable of anaerobic fermentation. The bottlenecks uncovered were resolved by insertion of three genes, and the recombinant strains were monitored through an adaptive laboratory evolution method with oxygen gradients set up specifically for this purpose. Recombinant strains were able to grow under micro-oxic conditions. Strain performance did not improve compared to the negative control under anoxic conditions. A more elaborate in-silico analysis was performed, combining protein domain analysis, transcriptomic analysis and genome-scale metabolic models to design a recombinant P. putida KT2440 strain capable of anaerobic respiration. Another general limitation in strains is their limited thermo-tolerance. We discovered a strong universal connection between NAD+ availability and thermo-tolerance. By replacing one single gene for a thermophilic heterolog in mesophilic prokaryotes, both P. putida and E. coli showed instant improved thermo-tolerance. Insertion of the aspartate NAD+ biogeneration pathway in eukaryotic yeast S. cerevisiae resulted in a similar effect. To determine the value of this thermo-tolerance in industry, a down-scaled microfluidics system was developed to mimic temperature fluctuations occurring in large scale bioreactors. The novel discovery between thermo-tolerance and NAD+ availabilty was patented
Aanzet Kennisprogramma Circulair Terreinbeheer : Landbouwkundig relevante eigenschappen van maaisel, bokashi en compost
Get PDFToepassing van maaisel uit bermen, openbaar groen en natuurgebieden voor een betere bodemkwaliteit sluit aan op de doelen van circulair terreinbeheer.In dit rapport zijn zowel de positieve effecten op bodemkwaliteit als de potentiële risico’s van drie bewerkingswijzen verkend: rechtstreeks onderwerken van maaisel, toepassing van bokashi en van compost. De beschouwde positieve effecten van het gebruik van organische bodemverbeteraars zijn onder meer koolstofvastlegging in de bodem na toepassing, nutriënten-leverend vermogen, ziektewerendheid en stimulering van de bodembiodiversiteit. Aan de andere kant komen aspecten als emissie van broeikasgassen, risico’s van accumulatie van zware metalen en onkruiddruk aan de orde. Voorts is aangegeven welke kennis nog ontbreekt. Het rapport sluit af met aanbevelingen voor een kennisagenda
Green Challenges : De ziekte- en plaagdichte kas
No full textPrevention is an important pillar in the control of diseases and pests in the greenhouse. This report gives an overview of the different routes of entry for pests and diseases, the importance of these routes, and methods and possibilities for prevention. The (semi-)closed greenhouse and a clean corridor for material and people could offer options to reduce risks of entry. Surveys and workshops with growers indicated that they questioned the importance of diseases and pests entering the greenhouse through ventilation windows, but that they saw perspective in a clean corridor. Therefore, the study paid specific attention to these topics. The importance of entry of winged insects by the ventilation openings was monitored but this limited trial did not reveal a strong relationship between the amount of insects outside and inside the greenhouse. A design has been made for a clean corridor, with detection and treatment options. In addition, the possibility of removing insects with an air shower and a detection method for mildew spores were specifically examined. The air shower does not seem to offer an effective and safe solution for horticulture at this time. The mildew spore pressure could be quantified with the selected approach. These are just two examples of an elimination and a detection tool that can be part of a clean corridor; it is recommended to investigate various other techniques as well
Forecasted freezing level height from the numerical weather prediction model HARMONIE-AROME
No full textDataset of forecasted freezing level height from the numerical weather prediction model HARMONIE-AROME cycle 38, as of 3 April 2018 cycle 40. HARMONIE-AROME is a non-hydrostatic regional numerical weather prediction model used operationally at the Royal Netherlands Meteorological Institute (KNMI) and various other European weather centers. At KNMI, the HARMONIE-AROME model operates at 2.5 times 2.5 km horizontal resolution and 65 vertical levels, and 48-hour long forecasts are initiated every three hours. A subset of the full output was archived on model-levels for a 300 times 300 cell domain covering part of the full 800 times 800 cell simulation domain. For each cell and simulation output time-step, the freezing level height was determined by scanning from the top of the atmosphere downwards to the first level for which the temperature reached 273.15K. The subset covers the Netherlands and surroundings, coinciding with the coverage of the two KNMI ground-based weather radars. This dataset has been employed for a study on rainfall-induced attenuation correction for two dual-pol C-band radars in the Netherlands, for which a paper is in preparation. For this, HARMONIE data which would have been available in real-time for coupling with real-time 5-min radar data were obtained, resulting in the selection of the forecasts with +2, +3, +4 or +5 h lead time, being available every 3 h (32 files per day). The HARMONIE data allow for distinguishing between rain and other types of precipitation. This dataset may also be useful for other (radar) applications