Serum HIV-1 RNA levels and time to development of AIDS in the Multicenter Hemophilia Cohort Study

Normal women produce small amounts of active androgens. When androgen levels are elevated, such as for example in the polycystic ovary syndrome, this is followed by the development of male physical characteristics and muscle mass, structure and function as well as android adipose tissue distribution and function. Psychological features and stress reactions also seem similar to those of men. Such women have an increased risk of developing hypertension, non-insulin-dependent diabetes mellitus and cardiovascular disease. Recent data have shown that these physical, and psychological characteristics, as well as risk of ill health, are also found in the population of women selected at random. Women in the lowest quintiles of levels of sex-hormone-binding globulin--an indicator inversely related to active androgens--are at risk of developing hypertension, non-insulin-dependent diabetes mellitus and cardiovascular mortality. The mechanism probably includes muscular insulin resistance, following a relative androgen excess. It is thus apparent that androgens, even within the highest levels of the nonselected population of women, are powerful predictors of serious disease development. The population at risk might be as large as about 20% of middle-aged women. This is an area of female disease risk which requires more attention in screening and intervention procedures.     

Wood‐Plastic‐Composites: Rheologische Charakterisierung und Füllverhalten im Spritzgießprozess

Wood‐plastic composites (WPC) show a complex and completely different material and flow behavior in comparison to pure polymers. Especially the flow behavior is very important for the processing of these composites. In the following article results of rheological characterization and investigations of the filling behavior during the injection molding process are presented. Furthermore, appearing challenges and possible methods of resolution are discussed.     

Dietary and host-related factors influencing carotenoid bioaccessibility from spinach (Spinacia oleracea)

Several dietary and host related factors potentially influencing carotenoid (beta-carotene, lutein and zeaxanthin) bioaccessibility from spinach, including different concentrations of sodium, calcium and magnesium, were systematically investigated by means of an in vitro digestion model. Bioaccessibility was highest when milk (4% fat) and lowest when skimmed milk or more complex food matrices such as sausage were added to the meal. Micellarisation significantly depended on the presence and concentration of bile salts and pancreatin (p < 0.001, Bonferroni) but was unaffected by pepsin. Micellarisation significantly decreased to 61.4 ± 3.0% of control (p < 0.001, Dunnett’s) at high cholesterol (114 mg/test meal) but not at similar stigmasterol concentrations. Calcium and magnesium ?13.8 mM individually inhibited micelle formation ( >40% on average), presumably due to the generation of insoluble soaps with fatty acids and bile salts. Increased sodium concentrations (280 and 460 mM) altered carotenoid micellarisation patterns, favoring beta-carotene isomers (p < 0.001, Bonferroni) but decreasing lutein and zeaxanthin (p < 0.001 and p < 0.05, respectively, Bonferroni). This study suggests that minerals may impact carotenoid bioavailability.     

Fracture properties of marble–mortar compounds

Marble panels for outdoor cladding of buildings are generally fastened with mortar and/or anchors. Due to environmental influences (e.g. solar heat, rain and snow), such panels can start to bow and crack, such that eventually they may detach from the wall, possibly causing damage to humans and the environment. Different marble–mortar compounds have been tested for their mechanical and fracture-mechanical characteristics (adhesive strength, notch tensile strength, specific fracture energy, crack growth resistance and characteristic length) by means of the pull-out test and the wedge-splitting method. The propagation of a crack in the marble–mortar compound is characterized on the basis of fracture-mechanics and by use of the load displacement curve. The advantages of using a mortar bed rather than anchors are considered.      

Metabolite channeling and compartmentation in the human cell line AGE1.HN determined by 13C labeling experiments and 13C metabolic flux analysis

This study focused on analyzing active pathways and the metabolic flux distribution in human neuronal AGE1.HN cells that is a desirable basis for a rational design and optimization of producing cell lines and production processes for biopharmaceuticals. ¹³C-labeling experiments and ¹³C metabolic flux analysis were conducted using glucose, glutamine, alanine and lactate tracers in parallel experiments. Connections between cytosolic and mitochondrial metabolite pools were verified, e.g., flux from TCA cycle metabolite ¹³C to glycolytic metabolites. It was also found that lactate and alanine are produced from the same pyruvate pool and that consumed alanine is mainly directly metabolized and secreted as lactate. Activity of the pentose phosphate pathway was low being around 2.3% of the glucose uptake flux. This might be compensated in AGE1.HN by high mitochondrial malic enzyme flux producing NADPH. Mitochondrial pyruvate transport was almost zero. Instead pyruvate carbons were channeled via oxaloacetate into the TCA cycle which was mainly fed via α-ketoglutarate and oxaloacetate during the investigated phase. The data indicate that further optimization of this cell line should focus on the improved substrate usage which can be accomplished by an improved connectivity between glycolytic and mitochondrial pyruvate pools or by better control of the substrate uptake.     

Towards a conceptualisation of quality in information technology projects

Quality has been extensively studied in repetitive operations, but it remains under-researched in projects. The uncertainty and dynamics of projects challenge the principles of quality developed for repetitive operations, and call for project-tailored solutions. This article explores the attributes of quality in projects, based on interviews conducted within a large IT-services company. An adapted repertory grid was used to investigate the understanding of quality by comparing concrete examples of projects considered as high or low quality. Eight attributes of quality were identified, which indicate a tension between a mechanistic standpoint of quality, and the need to incorporate less tangible aspects.     

Water diffusion in polymer nano-films measured with microcantilevers

We present a method to measure the absorption of water molecules from the liquid and the vapour phase into polymer nano-films and the diffusion inside these films. Film thickness can be down to 45 nm. To demonstrate the possibilities of this method we use polymer films that are deposited on the upper side of a silicon cantilever by plasma polymerization of norbornene. When a microdrop of water is deposited onto the initially straight cantilever, the drop causes the cantilever to bend while it evaporates. Evaporation of such small water drops usually takes less than a second. An upwards bending is due to capillary forces and a downwards bending is due to the diffusion of water into the polymer film – and the consequent volume expansion (swelling) of the film. The magnitude of the capillary forces and the extent of swelling continuously change during drop evaporation. When drop evaporation is over the cantilever returns to its initial straight position. We simulate the time dependent bending with a numerical model that qualitatively agrees with the experiment. From the time dependence of cantilever bending we are able to determine the diffusion coefficient of water in the thin polymer film.