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11.
Strain endurance experiments on a filled elastomer were performed at several temperatures. It was found that superimposed prestraining accelerated the ageing process. This process was caused by microstructural changes in the elastomer. In order to evaluate the mechanical properties of a filled elastomer it is necessary to take into consideration not only the ageing effects but also the loading history.  相似文献   
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We report a case of myasthenia gravis in a young Melanesian woman. It is only the second case described from Papua New Guinea and the first in which antibodies to the acetylcholine receptor have been demonstrated. The patient's complaint of occasional dysarthria was initially dismissed as hysterical in nature due to her apparent normal speech on conversation. The true nature of her problem only became apparent when she was asked to read a prolonged monologue. Myasthenia gravis may present without involvement of the eye muscles and the diagnosis may only become apparent if muscle groups are specifically tested for fatiguability.  相似文献   
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Innovation is often left to insight and serendipity. A lot of what researchers call innovation is actually a process by which one can make the individual consumer or practitioner more ‘creative’. Although it is important to work with the creative individual in hopes of coming up with the better ‘idea’ and new product/service opportunity, an equally valid albeit novel and counterintuitive approach systematizes creativity in a ‘research-driven machine’. This paper presents an approach to the systematization, based upon the point of view that creativity and innovation comprise the recombination of components into new blends. Given this point of view, to then spur innovation requires a systematic database that the user can access, with tools to help manipulate that database. The paper shows how such a database can be constructed and then used to create a novel product. The approach provides a general framework for the sensory professional to become more involved in the early stages of product development, where the focus is on the conceptual aspects of food features rather than on their physical manifestations in actual products.  相似文献   
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如今的数字信号处理器(DSP)在性能、外围设备集成、功耗和成本方面都具备很多优势,很多系统设计人员希望在原有系统设计中利用DSP获得比传统处理器更好的效益。但其中一个  相似文献   
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The application of the finite-difference time-domain (FDTD) method to various radiating structures is considered. These structures include two- and three-dimensional waveguides, flared horns, a two-dimensional parabolic reflector, and a two-dimensional hyperthermia application. Numerical results for the horns, waveguides, and parabolic reflectors are compared with results from using the method of moments (MM). The results for the hyperthermia application are shown as extensions of the previously validated models. This new application of the FDTD method is shown to be useful when other numerical or analytic methods cannot be applied  相似文献   
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在嵌入式应用中。随着“开源”C/C 代码越来越成为流行的用于替代基于版权算法的另一选择,挑战也随之而来。其中,最重要的问题是如何优化代码.使其在选定的处理器中更好地运行。本文将探讨开源算法在Blockfin处理器上的移植以及代码优化。  相似文献   
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Responsiveness, the ability to detect meaningful clinical change, is a critical attribute of instruments used to evaluate outcomes of treatments. The authors hypothesized that self-administered symptom severity and functional status questionnaires are more responsive to clinical improvement after carpal tunnel release than traditional physical examination measures of strength and sensibility. Data were obtained from a randomized clinical trial of endoscopic versus open carpal tunnel release conducted in four university medical centers. Patients were evaluated before surgery and 3 months after surgery. Seventy-four patients indicating that they were more than 80% satisfied with the results of surgery were assumed to have clinically meaningful improvement and were the focus of the analysis. Evaluations included questionnaires assessing symptom severity, functional status, and activities of daily living as well as measurement of grip, pinch, and abductor pollicus brevis strength, and 2-point discrimination and Semmes-Weinstein pressure sensibility. Responsiveness was calculated with the standardized response mean (mean change/standard deviation of change) as well as the effect size (mean change/standard deviation of baseline values). The symptom severity scale was four times as responsive, and the functional status and activities of daily living scales were twice as responsive, as the measures of strength and sensibility. Self-administered symptom severity and functional status scales are much more responsive to clinical improvement than measures of neuromuscular impairment and should severe as primary outcomes in clinical studies of therapy for carpal tunnel syndrome.  相似文献   
20.
A new technique for understanding the organization of complex circuits in the vertebrate brain, scanning laser photostimulation, is described. This approach is based on the photolysis of a caged form of the excitatory neurotransmitter glutamate. Computer-controlled photostimulation and whole cell recording in brain slices allow the construction of detailed maps of the position, strength, sign and number of inputs converging on a single postsynaptic neuron. Scanning laser photostimulation offers many advantages over current techniques: spatial resolution is superb, fibers of passage are not activated, and thousands of presynaptic locations can be stimulated. This review describes the technique of photostimulation, outlines the instrumentation, necessary to implement it, and discusses the interpretation of photostimulation-derived data. Several examples of applications, ranging from mapping circuits in the mammalian visual cortex to determining receptor distributions on single neurons are considered. Although still in its early stages, scanning laser photostimulation offers neuroscientists a powerful tool for determining the organization and function of local brain circuits.  相似文献   
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