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991.
 The physical phases of microsystem design are concerned with generating all data needed to fabricate microstructures. As lithography-based technologies are used to fabricate MEMS, this includes the design of two-dimensional mask layouts as well as the design of process step sequences and parameters which determine the object extensions in the third dimension. LIDO is a MEMS physical design system that supports this concurrent design strategy by providing tools to easily configure appropriate process sequences, to derive consistent sets of geometric layout design rules from them and to use these design rules to verify mask layouts. Received: 11 March August 1996 / Accepted: 1 August 1996  相似文献   
992.
993.
The recent creation of global-area computer networks invites the development of tools and resources that can reap the scholarly advantages of such technology. In this paper, we discuss prospects for the productive use of computer-mediated communication (CMC) for scholarly interaction. We begin by describing the technology used to deliver information over academic networks and the kinds of disciplinary services that the technology enables. In the second half of the paper we consider factors that bear upon the development of CMC-based disciplinary centers and we call attention to their potential to create a highly interactive form of scholarship.Teresa Harrison and Timothy Stephen are Associate Professors of Communication. Teresa Harrison's research focusses on communication theory and organizational communication. Timothy Stephen specializes in interpersonal communication and the development of community.This research was funded, in part, by the Paul Beer Trust, administered by the School of Humanities and Social Sciences, Rensselaer Polytechnic Institute.  相似文献   
994.
In the decades of 1960s–1980s, Air Force Materials Laboratory pioneered many programs and training of personnel that led to major advances in the understanding and utilization of composite materials and structures. The early involvement of industry resulted in rapid identification of the advantages and technical hurdles to be overcome. Through extensive use of postdoctoral appointments, ROTC at universities, visiting and exchange scientists, the Laboratory was able to reach many talented young people who in the years following have assumed leadership in teaching and research of composite materials worldwide. A recount of the activities during these three decades is timely because most of the “young” men and women who had spent time at the Laboratory will be ready to retire in the next few years.  相似文献   
995.
Legal decision-makers frequently assess the credibility of reports of traumatic victimization. In this study, we compared the memory features and post-traumatic symptoms associated with truthful and malingered reports of trauma. Participants (N=126) described in writing both a genuine and a fabricated traumatic experience (counterbalanced) and completed scales relating to the severity of the associated trauma symptoms. Relative to accounts of genuine trauma, the information in fabricated accounts was less plausible and contained fewer contextual details. However, truthful and false reports were qualitatively similar on other criteria such as coherence and relevance. Fabricated traumatic experiences were associated with extreme ratings on multiple, diverse psychological measures of emotional distress and a higher level of apparent post-traumatic stress disorder. However, most participants were able to "fool" widely used validity scales. Implications for evaluating the credibility of claims of victimization in legal cases are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
996.
In a cohort of gay men responding to the threat of AIDS, dispositional optimism was associated with less distress, less avoidant coping, positive attitudes as a coping strategy, and fewer AIDS-related concerns. Men who knew they were seropositive for HIV were significantly more optimistic about not developing AIDS than men who knew they were seronegative for HIV. This AIDS-specific optimism was related to higher perceived control over AIDS and to active coping among seropositive men only and to health behaviors in both serostatus groups. There was no relation of optimism to risk-related sexual behavior. It is concluded that optimism is psychologically adaptive without necessarily compromising health behavior. It is also concluded that it is useful to distinguish between event-based optimistic expectations and dispositional optimism. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
997.
998.
The synthesis and chemical compatibility of a ‘traceless’ thiohydroxamic acid (THA) linker is reported. The linker is shown to be stable to visible light and heat. This paper also describes preliminary work in the application of the THA linker to act as a polymer-supported source of radicals.  相似文献   
999.
Red wine contains a diversity of polyphenolic compounds that exert beneficial health effects including anti-cancer effects. This trial evaluated the anti-proliferative potential of red muscadine (Vitis rotundifolia) and red cabernet sauvignon (Vitis vinifera) wines in cell culture. Chemical properties of wines were determined by HPLC-PDA analysis and concentrated extracts of each wine were evaluated before and after glycosidic hydrolysis in MOLT-4 leukemia cells. Cell growth and the induction of apoptosis were evaluated after exposure to various extract dilutions. Wine extracts reduced cell viability up to 68% and cell numbers up to 50% after 48 h with muscadine extracts being more effective than cabernet sauvignon. Caspase-3 activity was induced similarly by all extracts in a dose dependent manner. Cell cycle arrest in the G2/M phase was observed for both muscadine and the non-hydrolyzed cabernet sauvignon extract. Collectively, extracts from both wines exerted anti-cancer effects in leukemia cells.  相似文献   
1000.
For the purpose of investigating the role of self-heating effects on the electrical characteristics of nano-scale devices, we implemented a two-dimensional Monte Carlo device simulator that self-consistently includes the solution of the energy balance equations for both, acoustic and optical phonons. We find less degradation in the current in smaller device structures because of the more pronounced velocity overshoot.  相似文献   
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