Studies of blood pressures in children, ages 5-14 years, in a total biracial community: the Bogalusa Heart Study

Blood pressure, height, weight, maturation, triceps skinfold thickness, serum lipids, and hemoglobin were measured as risk factors for coronary artery disease in 3,524 children (93% of the eligible population) in Bogalusa, Louisiana. Nine blood pressures were taken on each child by trained observers with mercury sphygmomanometers (Baumanometer) and Physiometrics automatic recorders in a rigid randomized design in a relaxed atmosphere with other children present. The pressures observed were low compared to reported data. Black children had significantly higher blood pressures than white children. This difference, starting before age 10, was largest in the children in the upper five percent of the pressure ranks. Stepwise multiple regression analysis revealed that this racial differnce was significant when measured by an automatic recorder. Body size, expressed by height and by weight/height3 index, was a strong determinant of blood pressure level. Other positive determinants were blood hemoglobin and external maturation.     

Calculation of cosmic ray limited maximum DC blocking voltages of high voltage silicon PIN diodes

A power law approach as used by Fulop for the treatment of impact ionization and breakdown in abrupt silicon P–N junctions [Fulop W. Calculation of avalanche breakdown voltages of silicon P–N junctions. Solid-State Electron. 1967;10:39–43] is developed in this paper to provide simple-to-use equations for the quantitative evaluation of cosmic ray related phenomena in high voltage power devices. Being empirical in nature, such approaches have no physical background and only serve the purpose of generating a simple and compact mathematical framework. The resulting compact model allows for a quick and straightforward computation of DC blocking voltages as a function of FIT rate, n-base doping and temperature. The determination of model parameters is based on the theory and data given in [Zeller HR. Cosmic ray induced failures in high power semiconductor devices. Solid-State Electron. 1995;38(12):2041–6]. With the new approach, calculating first-hand maximum DC blocking voltages for high voltage power semiconductor devices becomes as effortless as the calculation of the breakdown voltage.     

Optimization of the Liquid Distributor in a Falling Film Evaporator by Means of Air‐Water Experiments

Air‐water experiments (cold‐flow experiments) were performed for the liquid distributor of an industrial falling film evaporator (FFE). The feed to the FFE is superheated and a flash evaporation occurs in the head of the FFE. The aim of the experiments was to investigate the vapor‐liquid flow in the head and the resulting liquid distribution to the evaporator tubes. Several different designs of the distributor were investigated and explanations for the performance losses of the real evaporator over time were found. Several measures were finally concluded and also implemented for the real FFE.     

Effects of catch crops on silage maize (<Emphasis Type="Italic">Zea mays</Emphasis> L.): yield,nitrogen uptake efficiency and losses

Under the climatic conditions of north-western Europe, silage maize (Zea mays L.) production optimized with respect to nitrogen (N) fertilization and crop rotation is required to reduce N losses. Whether winter catch crops (CC) can serve as a beneficial biological tool in terms of N-loss abatement as well as maize yield also under optimized N management, is unclear. Therefore, a 2-year field experiment was conducted to study the short-term effects of a continuous maize-catch cropping system on maize yield performance, N₂O emission and N leaching, as affected by maize harvest/CC sowing date (10, 20, 30 September and 15 October, respectively, hd₁–hd₄) and CC species (rye, Secale cereale L. and Italian ryegrass, Lolium multiflorum Lam.). Treatments without CC served as control and N fertilization was applied as synthetic N to better adjust to maize N demand. The CC treatment (with or without) had no effect on maize dry matter and N yields, but the N uptake efficiency of maize responded significantly to the N accumulation (N_tot) of CC. Nitrate leaching mostly stayed below the critical load value for EU drinking water and rye significantly reduced nitrate leaching, given that environmental conditions allowed sufficiently high CC biomass accumulation. Annual nitrous oxide emission was unaffected by CC treatment. Restricted N fertilization of maize following CC led to N deficiency, since CC decomposition obviously was not synchronized with maize N demand. Under the given environmental conditions, rye may serve as beneficial CC in continuous maize cropping even in already optimized N management.     

Optisch aktive Amine durch Lipase-katalysierte Methoxyacetylierung

Optically Active Amines via Lipase-Catalyzed Methoxyacetylation Racemic amines can be efficiently resolved using ethylmethoxyacetate as acylating agent in a lipase-catalyzed reaction. The reaction of 1-phenyethylamine with ethylmethoxyacetate in the presence of a lipase from Burkholderia plantarii is presented. Excellent yields and selectivity and minimal amount of enzyme characterize this new process.     

Fluorescence Techniques Using Dehydroergosterol to Study Cholesterol Trafficking

Cholesterol itself has very few structural/chemical features suitable for real-time imaging in living cells. Thus, the advent of dehydroergosterol [ergosta-5,7,9(11),22-tetraen-3β-ol, DHE] the fluorescent sterol most structurally and functionally similar to cholesterol to date, has proven to be a major asset for real-time probing/elucidating the sterol environment and intracellular sterol trafficking in living organisms. DHE is a naturally occurring, fluorescent sterol analog that faithfully mimics many of the properties of cholesterol. Because these properties are very sensitive to sterol structure and degradation, such studies require the use of extremely pure (>98%) quantities of fluorescent sterol. DHE is readily bound by cholesterol-binding proteins, is incorporated into lipoproteins (from the diet of animals or by exchange in vitro), and for real-time imaging studies is easily incorporated into cultured cells where it co-distributes with endogenous sterol. Incorporation from an ethanolic stock solution to cell culture media is effective, but this process forms an aqueous dispersion of DHE crystals which can result in endocytic cellular uptake and distribution into lysosomes which is problematic in imaging DHE at the plasma membrane of living cells. In contrast, monomeric DHE can be incorporated from unilamellar vesicles by exchange/fusion with the plasma membrane or from DHE-methyl-β-cyclodextrin (DHE-MβCD) complexes by exchange with the plasma membrane. Both of the latter techniques can deliver large quantities of monomeric DHE with significant distribution into the plasma membrane. The properties and behavior of DHE in protein-binding, lipoproteins, model membranes, biological membranes, lipid rafts/caveolae, and real-time imaging in living cells indicate that this naturally occurring fluorescent sterol is a useful mimic for probing the properties of cholesterol in these systems.     

Chip integrated fuel cell accumulator

A unique new design of a chip integrated fuel cell accumulator is presented. The system combines an electrolyser and a self-breathing polymer electrolyte membrane (PEM) fuel cell with integrated palladium hydrogen storage on a silicon substrate. Outstanding advantages of this assembly are the fuel cell with integrated hydrogen storage, the possibility of refuelling it by electrolysis and the opportunity of simply refilling the electrolyte by adding water. By applying an electrical current, wiring the palladium hydrogen storage as cathode and the counter-electrode as anode, the electrolyser produces hydrogen at the palladium surface and oxygen at the electrolyser cell anode. The generated hydrogen is absorbed by the palladium electrode and the hydrogen storage is refilled consequently enabling the fuel cell to function.     

The job demands-resources model of burnout.

The job demands-resources (JD-R) model proposes that working conditions can be categorized into 2 broad categories, job demands and job resources, that are differentially related to specific outcomes. A series of LISREL analyses using self-reports as well as observer ratings of the working conditions provided strong evidence for the JD-R model: Job demands are primarily related to the exhaustion component of burnout, whereas (lack of) job resources are primarily related to disengagement. Highly similar patterns were observed in each of 3 occupational groups: human services, industry, and transport (total N?=?374). In addition, results confirmed the 2-factor structure (exhaustion and disengagement) of a new burnout instrument—the Oldenburg Burnout Inventory—and suggested that this structure is essentially invariant across occupational groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)