Possible implications of the presence of the raccoon dog (Nyctereutes procyonoides) in The Netherlands

Mogelijke implicaties van de aanwezigheid van de wasbeerhond (Nyctereutes procyoniodes) in Nederland. De soort is tussen 1929 en 1955 geïntroduceerd in Europese delen van de voormalige Sovjet Unie. Uit dit literatuuronderzoek blijkt dat de wasbeerhond sinds 1990 ook in Nederland is waargenomen

Aeroacoustic and flow assessments of the poro-serrated trailing edges

This paper reports an aeroacoustic study of a NACA0012 aerofoil with a nonflat plate type serrated trailing edge, and a number of Poro-Serrated trailing edge devices that contain porous materials of various air flow resistances at the gaps between adjacent members of the serrated sawtooth. Free field noise measurements were performed inside an aeroacoustic wind tunnel facility, where the range of jet speeds was between 20 ms-1 and 60 ms-1. Flow measurements were also conducted in the same facility for the very near wake. The main objective of this work is to determine whether multiple-mechanisms on the broadband noise reduction can co-exist on a poro-serrated trailing edge. The results demonstrate that having low flow resistivity at the sawtooth gaps could not completely suppress the vortex shedding tone at low frequency, but it can achieve reasonably well broadband noise reduction at high frequency. With high flow resistivity at the sawtooth gaps, the denser porous material almost renders the poro-serrated trailing edge to becoming a straight trailing edge again, thus undermining the serration effect and causing a drop in the noise performance. The optimal range of flow resistivity for the poro-serrated trailing edge is found to be around 10 kN.s.m-4, where it can even perform slightly better than the conventional serrated trailing edge in terms of the turbulent broadband noise reduction while still completely suppresses the vortex shedding noise. From the analysis of the wake data, the overall drag force will not increase when a poro-serrated trailing edge is used.The EPSRC Impact Acceleration Account – Readiness in the United Kingdom

Modelling job crafting behaviours: Implications for work engagement

In this study among 206 employees (103 dyads), we followed the job demands–resources approach of job crafting to investigate whether proactively changing one’s work environment influences employee’s (actor’s) own and colleague s (partner’s) work engagement. Using social cognitive theory, we hypothesized that employees would imitate each other’s job crafting behaviours, and therefore influence each other’s work engagement. Results showed that the crafting of social and structural job resources, and the crafting of challenge job demands was positively related to own work engagement, whereas decreasing hindrance job demands was unrelated to own engagement. As predicted, results showed a reciprocal relationship between dyad members’ job crafting behaviours – each of the actor’s job crafting behaviours was positively related to the partner’s job crafting behaviours. Finally, employee’s job crafting was related to colleague’s work engagement through colleague’s job crafting, suggesting a modelling process

Evaluatie van de landbouwregeling in de omzetbelasting

In artikel 27 Wet OB 1968 is de landbouwregeling uitgewerkt. Landbouwers, veehouders, tuinbouwers en bosbouwers zijn over prestaties genoemd in dit artikel geen omzetbelasting verschuldigd, maar hebben ook geen recht op aftrek van voorbelasting. De ondernemer kan opteren om in de heffing van de omzetbelasting te worden betrokken als een normale ondernemer. In deze evaluatie wordt onderzocht of de landbouwregeling op een doeltreffende (effectieve) en doelmatige (efficiënte) manier leidt tot het bereiken van de geformuleerde doelstelling. Daarnaast wordt aandacht besteed aan de neveneffecten van de regeling

De prijs van pensioenrisico

De afgelopen jaren is het aantal werknemers dat is aangewezen op een beschikbare premieregeling fors toegenomen. Simulaties laten zien dat het risico van deze nieuwe contracten groot is. Werknemers dragen onbewust dit hoge risico

Partitioning of melt energy and meltwater fluxes in the ablation zone of the west Greenland ice sheet

We present four years (August 2003–August 2007) of surface mass balance data from the ablation zone of the west Greenland ice sheet along the 67° N latitude circle. Sonic height rangers and automatic weather stations continuously measured accumulation/ablation and near-surface climate at distances of 6, 38 and 88 km from the ice sheet margin at elevations of 490, 1020 and 1520 m a.s.l. Using a melt model and reasonable assumptions about snow density and percolation characteristics, these data are used to quantify the partitioning of energy and mass fluxes during melt episodes. The lowest site receives very little winter accumulation, and ice melting is nearly continuous in June, July and August. Due to the lack of snow accumulation, little refreezing occurs and virtually all melt energy is invested in runoff. Higher up the ice sheet, the ice sheet surface freezes up during the night, making summer melting intermittent. At the intermediate site, refreezing in snow consumes about 10% of the melt energy, increasing to 40% at the highest site. The sum of these effects is that total melt and runoff increase exponentially towards the ice sheet margin, each time doubling between the stations. At the two lower sites, we estimate that radiation penetration causes 20–30% of the ice melt to occur below the surface

Creatine Kinase–Mediated ATP Supply Fuels Actin-Based Events in Phagocytosis

Phagocytosis requires locally coordinated cytoskeletal rearrangements driven by actin polymerization and myosin motor activity. How this actomyosin dynamics is dependent upon systems that provide access to ATP at phagosome microdomains has not been determined. We analyzed the role of brain-type creatine kinase (CK-B), an enzyme involved in high-energy phosphoryl transfer. We demonstrate that endogenous CK-B in macrophages is mobilized from the cytosolic pool and coaccumulates with F-actin at nascent phagosomes. Live cell imaging with XFP-tagged CK-B and β-actin revealed the transient and specific nature of this partitioning process. Overexpression of a catalytic dead CK-B or CK-specific cyclocreatine inhibition caused a significant reduction of actin accumulation in the phagocytic cup area, and reduced complement receptor–mediated, but not Fc-γR–mediated, ingestion capacity of macrophages. Finally, we found that inhibition of CK-B affected phagocytosis already at the stage of particle adhesion, most likely via effects on actin polymerization behavior. We propose that CK-B activity in macrophages contributes to complement-induced F-actin assembly events in early phagocytosis by providing local ATP supply

Distinct fermentation of human milk oligosaccharides 3-FL and LNT2 and GOS/inulin by infant gut microbiota and impact on adhesion of Lactobacillus plantarum WCFS1 to gut epithelial cells

Human milk oligosaccharides (hMOs) are unique bioactive components in human milk. 3-Fucosyllactose (3-FL) is an abundantly present hMO that can be produced in sufficient amounts to allow application in infant formula. Lacto-N-triaose II (LNT2) can be obtained by acid hydrolysis of lacto-N-neotetraose (LNnT). Both 3-FL and LNT2 have been shown to have health benefits, but their impact on infant microbiota composition and microbial metabolic products such as short-chain fatty acids (SCFAs) is unknown. To gain more insight in fermentability, we performed in vitro fermentation studies of 3-FL and LNT2 using pooled fecal microbiota from 12-week-old infants. The commonly investigated galacto-oligosaccharides (GOS)/inulin (9 : 1) served as control. Compared to GOS/inulin, we observed a delayed utilization of 3-FL, which was utilized at 60.3% after 36 h of fermentation, and induced the gradual production of acetic acid and lactic acid. 3-FL specifically enriched bacteria of Bacteroides and Enterococcus genus. LNT2 was fermented much faster. After 14 h of fermentation, 90.1% was already utilized, and production of acetic acid, succinic acid, lactic acid and butyric acid was observed. LNT2 specifically increased the abundance of Collinsella, as well as Bifidobacterium. The GOS present in the GOS/inulin mixture was completely fermented after 14 h, while for inulin, only low DP was rapidly utilized after 14 h. To determine whether the fermentation might lead to enhanced colonization of commensal bacteria to gut epithelial cells, we investigated adhesion of the commensal Lactobacillus plantarum WCFS1 to Caco-2 cells. The fermentation digesta of LNT2 collected after 14 h, 24 h, and 36 h, and GOS/inulin after 24 h of fermentation significantly increased the adhesion of L. plantarum WCFS1 to Caco-2 cells, while 3-FL had no such effect. Our findings illustrate that fermentation of hMOs is very structure-dependent and different from the commonly applied GOS/inulin, which might lead to differential potencies to stimulate adhesion of commensal cells to gut epithelium and consequent microbial colonization. This knowledge might contribute to the design of tailored infant formulas containing specific hMO molecules to meet the need of infants during the transition from breastfeeding to formula