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1.
Safron Adam; Barch Bennett; Bailey J. Michael; Gitelman Darren R.; Parrish Todd B.; Reber Paul J. 《Canadian Metallurgical Quarterly》2007,121(2):237
Men exhibit much higher levels of genital and subjective arousal to sexual stimuli containing their preferred sex than they do to stimuli containing only the nonpreferred sex. This study used event-related functional magnetic resonance imaging to investigate how this category-specific pattern would be reflected in the brains of homosexual (n = 11) and heterosexual (n = 11) men. Comparisons of activation to preferred sexual stimuli, nonpreferred sexual stimuli, and sports stimuli revealed large networks correlated with sexual arousal, spanning multiple cortical and subcortical areas. Both homosexual and heterosexual men exhibited category-specific arousal in brain activity. Within the amygdala, greater preference-related activity was observed in homosexual men, but it is unclear whether this is a cause or a consequence of their sexuality. In a subsequent analysis of regions hypothesized to support arousal, both participant groups demonstrated widespread increases in evoked activity for preferred stimuli. Aggregate data from these regions produced significant differences between stimulus types in 16 out of 22 participants. Significant activational differences matched reported sexual orientation in 15 of these 16 participants, representing an advance in psychophysiological measures of arousal. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The man-machine dialog is very important for the design process. In this paper a program system, based on the minicomputer KRS 4201 (ROBOTRON), is demonstrated by using an interactive graphical screen. This program system provides the opportunity to analyze and synthesize mechanisms up to 16 links. The application is demonstrated by designing a front-loader-system for a truck. Real-time animation of seven-bar linkages and coupler curves, including velocity and acceleration, are shown. 相似文献
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Reviews the book, The handbook of humanistic psychology: Leading edges in theory, research, and practice by Kirk J. Schneider, James F. T. Bugental, and J. Fraser Pierson (see record 2001-01409-000). Over 30 years ago Abraham Maslow (1971) envisioned a 3rd force psychology that would bring about “a change of basic thinking along the total front of man’s endeavors, a potential change in every social institution, in every one of the ‘fields’ of intellectual endeavor, and in every one of the professions.” Schneider, Bugental, and Pierson must have been guided by a similar vision as they edited the Handbook of humanistic psychology: Leading edges in theory, research, and practice. The breadth of the handbook is impressive with chapters addressing everything from psychotherapy, pedagogy, medicine, and spirituality to ecology, literature, social action and the workplace. The editors have successfully recruited authors from a variety of disciplines—including psychology, psychiatry, philosophy, education, and politics—who are well respected both inside and outside humanistic circles and who are exceptionally qualified to address their topics. Fortunately, despite this far-reaching breadth, the editors have not spread the handbook too thin. In fact, in areas where it seems especially needed (e.g., methodology) there is a much welcome depth and detail that is far from typical of other handbooks. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The available data suggest that lymph node involvement is an important prognostic factor in patients with carcinoma of the head of the pancreas. Lymph node metastases occur in as many as 50% of the cases of even the smallest pancreatic cancers now being diagnosed and resected (i.e., those < 2 cm in diameter). There is some evidence, especially from clinical experience in Japan, that wider lymphatic dissections (i.e., wider than those commonly done with the standard Whipple resection) may prolong survival. Unfortunately, many of the available data around the world are retrospective and are not randomized between the standard and the radical operation. Moreover, the pathologic material has not been staged uniformly according to accepted criteria. Thus the various series are not comparable. Comparisons between series require standardization with respect to stage of disease, pathologic classification, and treatment protocols. Before any modification of the standard pancreaticoduodenectomy is adopted, an appropriately designed study should be performed to test its efficacy. This study would also require a more comprehensive analysis of the pathologic material than is commonly performed today in the United States and Europe. 相似文献
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Direct epitaxial crystalline silicon thin film (CSiTF) solar cells on low-cost silicon sheets from powder (SSP) ribbons have been prepared using rapid thermal chemical vapour deposition (CVD) growth. The characterisation of CSiTF solar cells was investigated by electron and spectrally resolved light beam induced current (EBIC and SR-LBIC, respectively). All EBIC measurements were performed on both the front-side surface as well as on the cross-section of CSiTF solar cells. The electrical recombination was detected by EBIC and compared with their morphologies. The results of EBIC scan show that recombination centres are situated at grain boundaries (GBs); higher the density of grain, higher the recombination activities (higher contrast). Recombination of different intensity (strong and weak) takes place at vertical GBs. Compared with the high recombination at GBs, the contrast in intragrain is low. The dark contrast of the GBs and intragrain defects is clearly reduced near the surface due to the passivation by hydrogen, which indicates that the minority carrier diffusion length decreases gradually with the depth perpendicular to the surface. The diffusion length was determined by SR-LBIC. The results show that the diffusion length distribution is quite inhomogeneous over the whole cell area. A maximum Leff of about 25 μm and mean values around 15 μm are calculated for the best solar cell. 相似文献
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We report about the current performance of crystalline silicon thin-film (cSiTF) solar cells that are a very attractive alternative to conventional wafer-based silicon solar cells if sufficiently high cell efficiencies are achieved at acceptable cost of production. Applying a standard cell process (diffused POCl3 emitter, front contacts by photolithography, no surface texture) to thin-films deposited with a lab-type reactor, specifically designed for high-throughput photovoltaic applications, on highly-doped Cz substrates we routinely obtain efficiencies above 16%. On 1 Ω cm FZ material substrates we reach efficiencies up to 18.0%, which is among the highest thin-film efficiencies ever reported. Additionally, a comparison to microelectronic-grade epitaxially grown cSiTF material underlines the excellent electrical quality of the epitaxial layers deposited. 相似文献
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PU Reber MP Lewis AG Patel A Andren-Sandberg SW Ashley HA Reber 《Canadian Metallurgical Quarterly》1998,43(12):2610-2615
Ethanol is a common cause of both acute and chronic pancreatitis. Studies in other organs suggest that polymorphonuclear neutrophils activated by ethanol may cause tissue injury in a variety of conditions. The aim of this study was to investigate the effects of ethanol on neutrophil extravasation in the feline pancreas. Pancreata were isolated and perfused at different flow rates with varying concentrations of ethanol in either a physiological or neutrophil depleted perfusate. Neutrophil extravasation was assessed by measuring pancreatic tissue myeloperoxidase (MPO) activity. Ethanol at 2.5% (54.25 mmol/liter) was the lowest concentration that still caused significant neutrophil extravasation (3.1+/-0.8 vs 1.9+/-0.2 units, P<0.05) and was accompanied by an increase in vascular resistance of 15%. Reduction of pancreatic perfusion by 15% did not significantly increase neutrophil extravasation. (1.1+/-0.3 vs 1.6+/-0.2 units, NS) Perfusion of the pancreas with neutrophil-depleted blood containing either ethanol or saline, followed by perfusion with an ethanol-free perfusate, showed an increase in neutrophil extravasation in the ethanol group compared to the control group (3.2+/-0.9 vs 1.9+/-0.2 units, P<0.05). In conclusion, ethanol causes neutrophil extravasation in the feline pancreas independent of blood flow changes and occurs despite the absence of direct neutrophil exposure to ethanol. 相似文献
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Participants solving the Balls and Boxes puzzle for the first time were slowed in proportion to the level of working memory (WM) reduction resulting from a concurrent secondary task. On a second and still challenging solution of the same puzzle, performance was greatly improved, and the same WM load did not impair problem-solving efficiency. Thus, the effect of WM capacity reduction was selective for the first solution of the puzzle, indicating that learning to solve the puzzle, a vital part of the first solution, is slowed by the secondary WM-loading task. Retrospective verbal reports, tests of specific puzzle knowledge, and a recognition test of potential strategies all indicated that participants were unaware of their knowledge of the puzzle, suggesting that it had been learned implicitly. Concurrent protocols collected from participants supported this conclusion and further suggested that participants were not aware of learning to solve the puzzle as this learning occurred. These results provide evidence that implicit learning depends on WM capacity and that implicit memory can play an important role in problem solving. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献