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1.
The authors conducted an assessment study of newly developed motor performance items for the diagnosis of myopathy. 17 children who had had muscle biopsy for this diagnosis in the recent past were administered 14 items based on the measurement of static, dynamic and explosive muscle strength and muscle endurance. Individual items did not have perfect discriminative power, but the results were encouraging enough to warrant detailed study with combinations of the items, so that in future fewer children will have to undergo unnecessary muscle biopsies.  相似文献   
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Currently, in the photovoltaic industry, wet chemical etching technologies are used for saw damage removal and surface texturing. Alternative to wet chemical etching is plasma etching. However, as for example, the linear microwave plasma technique, developed by Roth&Rau, has not been implemented in the photovoltaic industry for etching, because of the very low etch rate (<1 µm/min) and the high cost of ownership related to the etching process. In this study, different front surface textured crystalline silicon wafers obtained by means of the linear microwave plasma technique and the expanding thermal plasma technique are investigated in terms of weighted reflection by using reflectometry (250–1200 nm) to study the optical properties of the textures in detail. In addition, atomic force microscopy is used to measure the surface topography to determine statistical roughness parameters, as presented in this paper. Effective light trapping can be obtained by multiple reflections as well as by a graded layer, which leads to a diffuse front surface, or a combination of both. A graded layer can be described as a smooth transition with increasing refractive index from air to silicon with typical thickness of (200 ± 50) nm. We have found that the average plane tilt angle correlates to the measured weighted reflection. Moreover, we can determine from the aspect ratio whether the light trapping is effective by multiple reflections. From the roughness exponent, which is a measure for the micro roughness, we can determine whether the light trapping is effective by a graded layer. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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G. Booch (see ibid., vol.SE-12, no.2, p.211-21, Feb. 1986) has analyzed a problem involving the software of a set of free-floating buoys. The correspondence points out that Booch's analysis fails to address one important system issue, namely the fact that the software must support two concurrent activities, and shows that an analysis according to the M.A. Jackson method will reveal this difficulty at an early design stage. On the other hand, the Jackson approach does not deal with some configuration issues, which are handled in Booch's analysis. This shows that one method is sometimes not enough to address all important, systemwide aspects of a problem. Rather than arguing about which one design method is best, the author recommends taking an electric view and using any combination of approaches that yields important results in a given situation  相似文献   
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There is a continuing interest in the fate of DNA from genetically modified organisms (GMO) in the food chain including the uptake of DNA by intestinal cells from dietary sources containing GM feed ingredients. The objective of this study was to elucidate the uptake and persistence of foreign DNA in the intestinal tract of Atlantic salmon Salmo salar L. using in situ hybridization (ISH) that enables the intracellular localization of the DNA, and polymerase chain reaction (PCR) to verify the ISH results qualitatively. Two salmon intestinal models were employed for the investigations; intestinal tissues were sampled in two models namely (a) in vivo from salmon-fed diets containing 30% GM soybeans or 30% nonGM (nGM) soybeans, and (b) ex vivo from intestinal sleeves incubated using different concentrations of PCR-amplified test DNAs (211 and 305 bp) designed from the 35S promoter/plant DNA junction of the RoundupReady soybean (RRS) genome. Additionally, for the incubation study, the effect of a mucolytic agent dithiothreitol (DTT) and a permeability enhancer sodium deoxycholate (SDA) on DNA uptake were investigated. Both treatments were found to enhance DNA uptake ex vivo. Dietary DNA and PCR-amplified DNA could be visualized by ISH in the salmon intestine with more frequently observed signals in the ex vivo model compared to the in vivo model. All results could be verified by PCR. Dietary DNA was localized in the cell vacuolar system and in lamina propria of the mid intestine. Thus, based on the investigated DNA fragment lengths, this study shows that foreign DNA, can be taken up by Atlantic salmon intestinal tissue.  相似文献   
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Aluminum-doped zinc oxide films exhibiting a rough surface morphology are deposited on glass substrates utilizing expanding thermal plasma. Spectroscopic ellipsometry is used to evaluate optical and electronic film properties. The presence of aluminum donors in doped films is confirmed by a shift in the zinc oxide bandgap energy from 3.32 to 3.65 eV. In combination with transmission reflection measurements in the visible and NIR ranges, charge carrier densities, optical mobilities, and film resistivities have been obtained from the free carrier absorption. Film resistivities are consistent with direct measurements, values as low as 6.0×10−4 ω cm have been obtained. The interdependence of electrical conductivity, film composition, and film morphology is addressed.  相似文献   
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Multi-product plants are very flexible units which are finding increasing use in the chemical industry, e. g. for the production of fine chemicals, pharmaceutical active compounds and automotive paints. Various concepts have become established for multi-product plants, depending on the area of use and existing conditions. Technical equipment fitting in with these plant concepts is characterized by standardization, multi-product suitability and a particularly broad area of use. The paper describes four multi-product plant concepts and suggests criteria for selecting the suitable concept for a particular case.  相似文献   
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