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81.
Basic mechanisms through which men and women self-regulate arousal have received little attention in human experimental addiction research, although stress-response-dampening and craving theories suggest an important role of emotional arousal in motivating alcohol use. This study examined gender differences in the effects of acute alcohol intoxication on psychophysiological and self-reported arousal in response to emotionally negative, positive, and neutral, and alcohol-related, picture cues. Thirty-six social drinkers (16 women) were randomly assigned to an alcohol, placebo, or control beverage group and exposed to picture cues every 10 s (0.1 Hz presentation frequency). Psychophysiological arousal was assessed via a 0.1-Hz heart rate variability (HRV) index. A statistically significant beverage group-by-gender interaction effect on psychophysiological, but not self-reported, arousal was found. The 0.1-Hz HRV responses to picture cues were suppressed by alcohol only in men. This gender-specific suppression pattern did not differ significantly across picture cue types. There were no significant gender differences in the placebo or control group. Greater dampening of arousal by alcohol intoxication in men, compared with women, may contribute to men’s greater tendency to use alcohol to cope with stress. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
82.
Amorphous Si (a-Si) films with lower hydrogen contents show better adhesion to glass during flash lamp annealing (FLA). The 2.0 µm-thick a-Si films deposited by plasma-enhanced chemical vapor deposition (PECVD), containing 10% hydrogen, start to peel off even at a lamp irradiance lower than that required for crystallization, whereas a-Si films deposited by catalytic CVD (Cat-CVD) partially adhere even after crystallization. Dehydrogenated Cat-CVD a-Si films show much better adhesion to glass, and are converted to polycrystalline Si (poly-Si) without serious peeling, but are accompanied by the generation of crack-like structures. These facts demonstrate the superiority of as-deposited Cat-CVD a-Si films as a precursor material for micrometer-thick poly-Si formed by FLA.  相似文献   
83.
Summary Static and dynamic light scattering measurements have been made on a sodium salt sample of succinoglycan in 0.01 M aqueous NaCl at different temperatures between 25 and 75°C where the polysaccharide undergoes a thermally induced change from an ordered (helical) to disordered conformation with raising temperature T. The weight-average molecular weight M w, the z-average radius of gyration, and the hydrodynamic radius sharply decrease in a relatively narrow T range (around 55°C) in which the specific rotation was previously found to change sigmoidally with T. In particular, the value of M w (4.55 × 105) in the ordered state at 25°C is twice as large as that (2.27 × 105) in the disordered state at 75°C, giving decisive evidence that the helical structure of the polysaccharide in aqueous NaCl is composed of paired chains. It is concluded that this structure is a double-stranded helix and breaks directly into two disordered chains with increasing T. Received: 6 July 2001 / Accepted: 24 July 2001  相似文献   
84.
85.
Abstract

Ba1?x Sr x TiO3 thin film capacitors have been successfully prepared using rf-sputtering and a metal organic deposition (MOD) method. The structure, microstructure and composition of the BSTO films are presented. Films grown on lanthanum aluminate LAO(100) showed c-axis preferred growth orientation. Broad paraelectric-to-ferroelectric transitions were observed in films prepared by both methods. The tunability of the capacitance by means of an appplied electric field is examined using various capacitor geometries. A decrease in the capacitance exceeding 75% at 77 K was obtained from the MOD deposited films under an electric field strength of 0.3 MV/cm. On the other hand, the tunability of the capacitance in the rf-sputtered films ranged from 5 to 10% at 77 K and at 20 kV/cm, while it exceeds 50% in some films. The results are compared with the predictions of Devonshire's phenomenological theory.  相似文献   
86.
The leaching behavior of Na from soda–lime–silicate glass was investigated by preparing glass powders with average particle diameters of 53 and 19 μm, and leaching in HNO3 at 90°−140°C. A new theoretical equation for Na leaching from a spherical particle is proposed based on the assumption that a rate-determining process is the three-dimensional self-diffusion of Na in glass. The diffusion constant ( D ) of Na in glass was obtained by fitting the experimental data to a theoretical equation. The values of D and activation energy obtained are comparable to those obtained in other studies on larger particles.  相似文献   
87.
We isolated three highly homologous genes, PIR1, PIR2 and PIR3, collectively called the PIR genes. The remarkable feature of their putative amino acid sequence is that they contain a sequence consisting of 18–19 amino acid residues repeated tandemly seven to ten times. Genes homologous to PIR were found in Kluyveromyces lactis and Zygosaccharomyces rouxii but not in Schizosaccharomyces pombe, suggesting that a set of PIR genes plays some role in budding yeast. Bias of codon usage seen in each of the PIR translation products suggests that they are expressed abundantly. The fact that disruption of each gene is viable indicates that none of them is essential. The double disruptants, pir1 pir2, were viable under various conditions, such as higher temperature (37°C) or high salt concentration, but showed a slow-growing phenotype on an agar slab. Furthermore, they were sensitive to heat shock. Addition of a pir3 disruption to the pir1 pir2 double disruptant brought about no phenotypic difference from the original double mutant. PIR1 and PIR3 are closely linked to each other and are on chromosome XI.  相似文献   
88.
This paper presents the preparation, results and analysis of the BioNLP’09 shared task on event extraction, organized to address the automatic extraction of fine‐grained information from the scientific literature on molecular biology. A representation of this information was defined taking into account both the biological and computational requirements of the task, and corpus resources manually annotated by domain experts provided to task participants. To create a basis for further progress, emphasis was placed on providing fine‐grained evaluation that isolates different subtasks and allows the analysis of different aspects of the results through various evaluation criteria. In introducing this new task to the community, we made an effort to reduce the cost of participation by making common natural language processing tools, data, and evaluation methods easily accessible. The task received community‐wide participation, establishing the state‐of‐the‐art performance at fine‐grained event extraction as well as allowing the identification of remaining challenges and suggesting directions for future improvements. All the resources and results of the shared task are publicly available and an online evaluation on blind test data accessible at http://www‐tsujii.is.s.u‐tokyo.ac.jp/GENIA/SharedTask/ .  相似文献   
89.
The melt spinning of Pb-Bi-Ge alloys with Pyrex glass was investigated as a means of producing a superconducting long filament with highT c. Continuous filaments with maximumT c of more than 10 K of Pb100-x-y Bi x Ge y (15x37 and 725) were obtained from the molten state at 1500 K with a winding speed of 0.95 m sec–1. The Pb49Bi33Ge18 filament, which was 34×10–6 m diameter and a ductile material with a tensile strength of 20 MPa and elongation of 2.7%, exhibited superconductivity at the highestT c of 14.3 K. These filaments were found to be polycrystalline with a grain size of more than 5000×10–10 m and had a mixed structure of germanium (diamond) (h c p) and bismuth phases. The germanium element distributed homogeneously in the filament.  相似文献   
90.
High toughness glass-coated metallic fibres show great promise for use in composite materials as reinforcement for brittle matrixes such as fine ceramics. This paper describes the glass-coated melt spinning of austenitic steel and Fe-B base alloys in order to prepare a ductile high strength filament. The toughness was estimated from the area of the stress-strain curves of the filament obtained. Continuous high toughness steel filament, which had a maximum toughness of 6600 MPa% with a tensile strength of 3050 MPa and an elongation of 3.1% was obtained from the molten state at 1600 K for a winding speed of 7.95 m sec–1. The filament was 3×10–6m diameter and polycrystalline with a grain size of 1000×10–10m. The crystal structure of the filament was a single b c c phase and the phase transformed into a stable f c c structure by heat treatment at 1073 K for 600sec. Ductile filaments of Fe78-x Co5Ni5Cu2B10M x (M x Cr5–20, Cr5Si3, Cr5Co5, Cr5Ni5, Cr10Mo0.5, Cr10Nb0.5) alloys were also successfully produced. The Fe67.5Co5Cr10Ni5Cu2B10Mo0.5 filament had the highest toughness of 13 900 MPa% with tensile strength of 3760 MPa and an elongation of 4.8%. The filament had a single b c c phase.  相似文献   
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