Linoleic acid intake, plasma cholesterol and 10-year incidence of CHD in 20.000 middle-aged men and women in the Netherlands

We studied the associations of a difference in linoleic acid or carbohydrate intake with plasma cholesterol levels and risk of CHD in a prospective cohort study in the Netherlands. Data on diet (FFQ) and plasma total and HDL-cholesterol were available at baseline (1993–7) of 20 069 men and women, aged 20–65 years, who were initially free of CVD. Incidence of CHD was assessed through linkage with mortality and morbidity registers. During an average of 10 years of follow-up, 280 CHD events occurred. The intake of linoleic acid ranged from 3·6 to 8·0 % of energy (en%), whereas carbohydrate intake ranged from 47·6 to 42·5 en% across quintiles of linoleic acid intake. Linoleic acid intake was inversely associated with total cholesterol and HDL-cholesterol in women but not in men. Linoleic acid intake was not associated with the ratio of total to HDL-cholesterol. No association was observed between linoleic acid intake and CHD incidence, with hazard ratios varying between 0·83 and 1·00 (all P>0·05) compared to the bottom quintile. We conclude that a 4–5 en% difference in linoleic acid or carbohydrate intake did not translate into either a different ratio of total to HDL-cholesterol or a different CHD incidenc

High Frequency Plasma Generators for Ion Thrusters

The results of a one year program to experimentally adapt two new types of high frequency plasma generators to Argon ion thrusters and to analytically study a third high frequency source concept are presented. Conventional 30 cm two grid ion extraction was utilized or proposed for all three sources. The two plasma generating methods selected for experimental study were a radio frequency induction (RFI) source, operating at about 1 MHz, and an electron cyclotron heated (ECH) plasma source operating at about 5 GHz. Both sources utilize multi-linecusp permanent magnet configurations for plasma confinement. The plasma characteristics, plasma loading of the rf antenna, and the rf frequency dependence of source efficiency and antenna circuit efficiency are described for the RFI Multi-cusp source. In a series of tests of this source at Lewis Research Center, minimum discharge losses of 220+/-10 eV/ion were obtained with propellant utilization of .45 at a beam current of 3 amperes. Possible improvement modifications are discussed

Modelling the Effects and Costs of Colorectal Cancer Screening

__Abstract__ The thesis focused on the potential effects and costs of population-based colorectal cancer (CRC) screening by considering two overarching questions. In the first part of the thesis the potential impact of current screening policies on the CRC disease burden and costs in the population was investigated. In this part the situations in the US as a whole, the states of Louisiana and New Jersey in par

Global Justice and the Shift in Property Rights for Plant Genetic Resources

Although new technologies in plant breeding have the potential to reduce poverty and improve global food security, a shift in property regime for plant genetic resources (PGRs) prevents this potential from being realised. As the emergence of biotechnology has increased the value of PGRs, rents-seeking behaviour by the plant breeding industry spurred the emergence of intellectual property rights (IPRs) for improved plant varieties. Whereas this system is globally implemented through the TRIPS agreement, biodiversity-rich developing countries increasingly use the Convention on Biological Diversity (CBD) to protect their PGRs through state sovereignty. By using an economic perspective, this article aims to explain the appropriation of PGRs and the efficiency rationale that is used for its justification. However, as this perspective disregards the alarming consequences for smallholder farmers in developing countries, a global justice perspective is used to explore these effects. Focusing on distributional justice and the provision of the right to food, this article will demonstrate that the property regime shift for PGRs leads to decreased availability of, and access to, crops that are used by resource-poor farmers. Instead of promoting organic agricultural practices, based on the diversity of traditional seed systems and minimal external inputs, this regime merely stimulates the growth of an unsustainable and highly concentrated seed industry. The International Treaty on Plant Genetic Resources for Food and Agriculture (ITPGRFA) and Consultative Group on International Agriculture Research (CGIAR) seem to be most promising in challenging the shift in property regime for PGRs and the global justice concerns this shift entails

Sprays from droplets impacting a mesh

In liquid spray applications, the sprays are often created by the formation and destabilization of a liquid sheet or jet. The disadvantage of such atomization processes is that the breakup is often highly irregular, causing a broad distribution of droplet sizes. As these sizes are controlled by the ligament corrugation and size, a monodisperse spray should consist of ligaments that are both smooth and of equal size. A straightforward way of creating smooth and equally sized ligaments is by droplet impact on a mesh. In this work we show that this approach does however not produce monodisperse droplets, but instead the droplet size distribution is very broad, with a large number of small satellite drops. We demonstrate that the fragmentation is controlled by a jet instability, where initial perturbations caused by the injection process result in long-wavelength disturbances that determine the final ligament breakup. During destabilization the crests of these disturbances are connected by thin ligaments which are the leading cause of the large number of small droplets. A secondary coalescence process, due to small relative velocities between droplets, partly masks this effect by reducing the amount of small droplets. Of the many parameters in this system, we describe the effect of varying the mesh size, mesh rigidity, impact velocity, wetting properties, keeping the liquid properties the same by focusing on water droplets only. We further perform Lattice Boltzmann modeling of the impact process that reproduces key features seen in the experimental data.Comment: 11 pages, 12 figures, 6 supplemental movies (not included

Soil biological quality of grassland fertilized with adjusted cattle manure slurries in comparison with organic and inorganic fertilizers

We studied the effect of five fertilizers (including two adjusted manure slurries) and an untreated control on soil biota and explored the effect on the ecosystem services they provided. Our results suggest that the available N (NO3- and NH4+) in the soil plays a central role in the effect of fertilizers on nematodes and microorganisms. Microorganisms are affected directly through nutrient availability and indirectly through grass root mass. Nematodes are affected indirectly through microbial biomass and grass root mass. A lower amount of available N in the treatment with inorganic fertilizer was linked to a higher root mass and a higher abundance and proportion of herbivorous nematodes. A higher amount of available N in the organic fertilizer treatments resulted in a twofold higher bacterial activity (measured as bacterial growth rate, viz. thymidine incorporation), a higher proportion of bacterivorous nematodes, a 30% higher potential N mineralization (aerobic incubation), and 25–50% more potentially mineralizable N (anaerobic incubation). Compared to inorganic fertilizer, organic fertilization increased the C total, the N total, the activity of decomposers, and the supply of nutrients via the soil food web. Within the group of organic fertilizers, there was no significant difference in C total, abundances of soil biota, and the potential N mineralization rate. There were no indications that farmyard manure or the adjusted manure slurries provided the ecosystem service “supply of nutrients” better than normal manure slurry. Normal manure slurry provided the highest bacterial activity and the highest amount of mineralizable N and it was the only fertilizer resulting in a positive trend in grass yield over the years 2000–2005. The number of earthworm burrows was higher in the treatments with organic fertilizers compared to the one with the inorganic fertilizer, which suggests that organic fertilizers stimulate the ecosystem service of water regulation more than inorganic fertilizer. The trend towards higher epigeic earthworm numbers with application of farmyard manure and one of the adjusted manure slurries, combined with the negative relation between epigeic earthworms and bulk density and a significantly lower penetration resistance in the same fertilizer types, is preliminary evidence that these two organic fertilizer types contribute more to the service of soil structure maintenance than inorganic fertilize

Microscopic Mechanism of Specific Peptide Adhesion to Semiconductor Substrates

The design of hybrid peptide-solid interfaces for nanotechnological applications such as biomolecular nanoarrays requires a deep understanding of the basic mechanisms of peptide binding and assembly at solid substrates. Here we show by means of experimental and computational analyses that the adsorption properties of mutated synthetic peptides at semiconductors exhibit a clear sequence-dependent adhesion specificity. Our simulations of a novel hybrid peptide-substrate model reveal the correspondence between proline mutation and binding affinity to a clean silicon substrate. After synthesizing theoretically suggested amino-acid sequences with different binding behavior, we confirm the relevance of the selective mutations upon adhesion in our subsequent atomic force microscopy experiments.Comment: 14 pages, 4 figure