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11.
This study evaluated relations among optimism, perceived stress management skills (PSMS), and positive mood in 46 men who had surgical treatment for localized prostate cancer. The authors found that optimism, PSMS, and positive mood scores were positively correlated. Positive mood was unrelated to demographic and disease-related control variables. In a hierarchical regression model controlling for PSMS, the relationship between optimism and positive mood became nonsignificant, whereas PSMS remained a correlate of positive mood. Results suggest that the relationship between optimism and positive mood may be mediated by belief in being able to use stress management techniques effectively. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Roasting coffee led to a drop in the ochratoxin A (OTA) concentration, as measured by the reference method, especially for dark type roasts. The way the beverage was prepared also affected the OTA content, which could paradoxically be higher than that of the initial roasted coffee. Assays on the thermal stability of pure OTA showed that it ought to be found in larger quantities in roasted coffee. This suggested that OTA was masked by reactions with the substrate during roasting. The absence of OTA in green coffee is therefore the best guarantee of safety.  相似文献   
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We report on a single‐layer organic memory device made of poly(N‐vinylcarbazole) embedded between an Al electrode and ITO modified with Ag nanodots (Ag‐NDs). Devices exhibit high ON/OFF switching ratios of 104. This level of performance could be achieved by modifying the ITO electrodes with some Ag‐NDs that act as trapping sites, reducing the current in the OFF state. Temperature dependence of the electrical characteristics suggest that the current of the low‐resistance state can be attributed to Schottky charge tunnelling through low‐resistance pathways of Al particles in the polymer layer and that the high‐resistance state can be controlled by charge trapping by the Al particles and Ag‐NDs.  相似文献   
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A manufacturability evaluation decision model is formulated and analyzed based on fuzzy logic and multiple attribute decision-making under the concurrent engineering environment. The study emphasizes on the treatment of the linguistic and vagueness at the early product development stage. The study also considers the function integration of the total life cycle of a product. Hence, the integrated decision model covers the multi-level, multi-goal requirements of the products. Multiple criteria such as the goal space, the decision space, the function space, the development (i.e., product & process design) space, and the activity space, are then applied under different analysis of decision-making methods. For instances, the fuzzy multiple attribute decision-making (FMADM) combined with activity-based costing (ABC) can be used in the activity decision space. The fuzzy logic decision model can be applied in the goal decision space. The results of this study point out the importance of early decision making capability. An example of a high-pressure vessel is provided to demonstrate the proposed model for evaluating the manufacturability.  相似文献   
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The determination of planar properties—cross sectional areas, centroids, moments of inertia, and so forth—plays a central role in the solution of many diverse engineering problems. Despite the increasing availability of computational power to engineers and students alike in recent years with the advent of small desktop computers, however, the traditionally laborious and error-prone methods of making these determinations, involving area decomposition or strip integration, are still being taught to the present generation of engineering students, mostly due to a lack of suitable alternative techniques. These classical methods are found to be particularly difficult to adapt to general computational algorithms. This work presents a novel approach, requiring only the peripheral points of any planar area as inputs, and is ideally suited for numerical methods. It is shown that all planar properties of technical interest can be generated, once and for all, with straightforward algorithms that are readily programmed in any scientific computing language, or adapted to typical spreadsheet formats. These algorithms are fully general and require no decision-making on the part of the user. Various worked examples are presented.  相似文献   
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This study was motivated by some difficulties encountered by the authors when trying to express temporal knowledge using Sowa's conceptual graph (CG) approach. An overview of Sowa's approach is given and the difficulties encountered when trying to model temporal knowledge are outlined: the disparity of notations allowed by CG theory for expressing temporal information; the ambiguity and incompleteness of tense sspecification; the difficulty of harmonizing tenses and intergraph temporal relations. Various approaches suggested for representing time both in artificial intelligence and linguistics are presented, and an extension to Sowa's approach is proposed in which temporal and nontemporal knowledge are differentiated. In this model points in time are represented as well as time intervals. A semantic interpretation of verbs is provided based on an extension of Reichenbach's model of temporal markers. The authors show how their approach enables the representation of tenses as well as the aspectual properties of natural language sentences.  相似文献   
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We examined spatial-temporal patterns of neural activity, as inferred from 700 nm light reflectance, from the dorsal hippocampus and surrounding neocortex in seven freely behaving cats following 1.5, 2.5, 3.5 and 5.0 mg/kg intravenous cocaine administration. Images were acquired using a new technique which gathered reflected light from cortical and subcortical structures. Cardiac and respiratory patterning, collected simultaneously with optical images, revealed increased rates and diminished variation after intravenous cocaine administration. Cocaine increased reflectance correlates of hippocampal neural activity in a dose-dependent fashion over a 120 min period, with a lengthening time-to-peak effect (22-76 min). The largest dose resulted in an initial decrease, followed by the greatest enhancement in neuronal activity. Correlates of neural activation in the neocortex displayed an inverse dose-response curve to that found in the hippocampus; the time-to-peak effect was shorter (6-43 min) and the maximal change was reduced. Regional patches and bands of activation occurred during the period of the cocaine response, and were more pronounced in the hippocampus than the neocortex. Procaine, administered in a similar dose, slightly increased neural activity for 10 min in both the hippocampus and neocortex, and elicited a small increase in respiration. Cocaine induces a pronounced enhancement of neural activation in the neocortex and dorsal hippocampus; the time course of activation in the hippocampus parallels an increased respiratory pattern and outlasts the neocortical response. We speculate that hippocampal activation may be related to the profound respiratory acceleration found in response to cocaine.  相似文献   
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