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991.
992.
The results of a pluridisciplinary epidemiological study carried out on a series of 225 adults from rural areas, in whom the prevalence of arterial hypertension disease (AHTD) and borderline (AHTB) was of 19.0% and 14.4%, respectively, are presented. In 19.0% of the carriers of over five associated risk factors for cardiovascular disease, the classical lipid constants (triglycerides-TG. total lipids-TL. total cholesterol-TC. HDL-cholesterol-HDL-c), plasma (PML) and erythrocyte magnesium level (EML), as compared to the degree of drinking water mineralization were determined. The environmental conditions, also expressed in water hardness (21.650 G) or magnesium water intake (85.13 mg/l) correlate in 41.0% of the subjects with a decrease in PML (1.8 mg/l) and in 70.48 with a decrease in EML (4.8 mg/l) through the association of some behavioral or metabolic risk factors: stress, consumption of atherogenic foods, excess alcohol and lipid dysmetabolism (TG: 130-140 mg/l = 59.5%; TL: 8 g%-30.9%; TC: 220 mg/l = 19%; HDL-c: 35 mg/l + 1.9%).  相似文献   
993.
According to contingent-processing accounts, peripheral cuing effects are due to the cues' inadvertent selection for processing by control settings set up for targets (e.g., C. L. Folk, R. W. Remington, & J. C. Johnston, 1992). Consequently, cues similar to targets should have stronger effects than do dissimilar cues. In the current study, this prediction is confirmed for cue-target combinations similar or dissimilar in the static features of color (Experiments 1-3) and location (Experiment 4), even when both cues and targets share the dynamic feature of abrupt onset. Perceptual priming (Experiment 2) and reallocation of attention did not account for similar-dissimilar differences (Experiments 3 and 4). The results are best explained by top-down-contingent attentional effects of the similar cues. Implications for bottom-up accounts of peripheral cuing effects are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
994.
995.
996.
Summary Several dialkoxicarbenium ions have proved to initiate the cationic polymerization of styrene. In order to elucidate the mechanism of initiation, some of these dialkoxicarbenium ions were reacted with 1.1-diphenyl ethene and the reaction products are described.  相似文献   
997.
Electron microscopic investigations of magnetron sputtered amorphous SiNx-coatings showed, that morphology changes with variation of working gas pressure and substrate position corresponding to the Structure Zone Model by Thornton. Increasing working gas pressure and displacement of substrate to larger radial distances influence columnar structures. Energy of particles and adatom mobility decrease with increasing pressure. In positions far from the centre of deposition there are more particles with oblique incidence. This leads to a shadowing mechanism. Columnar diameter increases and packing density decreases. The influence of working gas pressure and angle of incidence bears also an effect on the behaviour of mechanical stress. Coatings with coarse columnar structures have lower mechanical stress than coatings with fine columnar structures.  相似文献   
998.
999.
Grain Boundary Films in Rare-Earth-Glass-Based Silicon Nitride   总被引:2,自引:0,他引:2  
The thickness of the intergranular films in Si3N4 densified with lanthanide oxides has been systematically investigated using high-resolution transmission electron microscopy. Four lanthanide oxides—La2O3, Nd2O3, Gd2O3, and Yb2O3—as well as Y2O3 are chosen so that the results will reflect the overall trend in the effect of the lanthanide utilized. The film thicknesses increase with increasing ionic radius of the lanthanide. In addition, Si3N4 particles flocculated into isolated clusters in the lanthanide-based glasses are also characteristically separated by an amorphous film whose thickness is similar to that in the comparable polycrystalline ceramics, demonstrating that the film thickness is dictated entirely by the composition and not by the amount of the glass phase present.  相似文献   
1000.
This paper presents the design of a new multiplier architecture for normal integer multiplication of positive and negative numbers as well as for multiplication in finite fields of order 2n. It has been developed to increase the performance of algorithms for cryptographic and signal processing applications on implementations of the Instruction Systolic Array (ISA) parallel computer model [M. Kunde, H.W. Lang, M. Schimmler, H. Schmeck, H. Schröder, Parallel Computing 7 (1988) 25-39, H.W. Lang, Integration, the VLSI Journal 4 (1986) 65-74]. The multiplier operates least significant bit (LSB)-first for integer multiplication and most significant bit ( )-first for finite field multiplication. It is a modular bit-serial design, which on the one hand can be efficiently implemented in hardware and on the other hand has the advantage that it can handle operands of arbitrary length.  相似文献   
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