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Wireless Personal Communications - In recent years, the emergence of Internet of things and cyber-physical system provide a proactive and efficacious solution to enable remote monitoring, machine... 相似文献
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BS Kendrick BS Chang T Arakawa B Peterson TW Randolph MC Manning JF Carpenter 《Canadian Metallurgical Quarterly》1997,94(22):11917-11922
Understanding the mechanism for sucrose-induced protein stabilization is important in many diverse fields, ranging from biochemistry and environmental physiology to pharmaceutical science. Timasheff and Lee [Lee, J. C. & Timasheff, S. N. (1981) J. Biol. Chem. 256, 7193-7201] have established that thermodynamic stabilization of proteins by sucrose is due to preferential exclusion of the sugar from the protein's surface, which increases protein chemical potential. The current study measures the preferential exclusion of 1 M sucrose from a protein drug, recombinant interleukin 1 receptor antagonist (rhIL-1ra). It is proposed that the degree of preferential exclusion and increase in chemical potential are directly proportional to the protein surface area and that, hence, the system will favor the protein state with the smallest surface area. This mechanism explains the observed sucrose-induced restriction of rhIL-1ra conformational fluctuations, which were studied by hydrogen-deuterium exchange and cysteine reactivity measurements. Furthermore, infrared spectroscopy of rhlL-1ra suggested that a more ordered native conformation is induced by sucrose. Electron paramagnetic resonance spectroscopy demonstrated that in the presence of sucrose, spin-labeled cysteine 116 becomes more buried in the protein's interior and that the hydrodynamic diameter of the protein is reduced. The preferential exclusion of sucrose from the protein and the resulting shift in the equilibrium between protein states toward the most compact conformation account for sucrose-induced effects on rhIL-1ra. 相似文献
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The design and simulation of a bit-sliced processor for relational database aggregation functions, are discussed. The processor, which addresses an important, computationally expensive problem in database computers, takes two tuples as input (one bit at a time) and returns two bits as output every clock cycle. A larger aggregation unit uses a number of identical slice processors, connected according to odd-even network topology, to achieve improved performance on a parallel pipelined processor. The data processing time is completely overlapped with the input and output of data to and from the unit. The design is independent of the tuple size, and since a bit-serial computation is used, the system requires limited interconnection 相似文献
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Sood Johanna R.; Cisek Edward; Zimmerman Joan; Zaleski Ellen H.; Fillmore Herbert H. 《Canadian Metallurgical Quarterly》2003,48(1):44
Objective: To replicate and extend P. A. Lichtenberg and colleagues' (1996) cross-disciplinary intervention to improve physical and mental health among older adults. Participants: 14 depressed older adults (6 treatment, 8 control). Setting: The short-term rehabilitation unit of an urban nursing home. Intervention: Occupational therapists were trained to treat depression using pleasant events and cognitive-behavioral therapies. Outcome Measures: Geriatric Depression Scale, the Short Form-12, and the Multi-Level Assessment Instrument: Activities of Daily Living. Results: No significant group differences were found in physical or mental health. However, more control group members (75%) than treatment group members (33%) were depressed at study completion. Conclusions: The treatment of depressive symptoms can be integrated with a nonmental health treatment modality. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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Because many testicular toxicants cause damage to specific stages of spermatogenesis, the present study has investigated the utility of a model in which the testis is synchronized to contain only a few closely related spermatogenic stages. The susceptibility of different stages to 1,3-dinitrobenzene (1,3-DNB) toxicity was investigated in rats, the testes of which had been stage synchronized by a vitamin A depletion/repletion (VADR) procedure. 1,3-DNB (25 mg/kg, IP) or vehicle was injected 58, 61, or 78 d after vitamin A readministration, and testicular histopathology was evaluated 48 h later. At the time of sacrifice, testes in the three groups were synchronized to stages I-VI, VII-IX, or X-XIV+I. The data indicated that tubules in all stages of spermatogenesis, in both synchronized and unsynchronized animals, demonstrated histopathologic changes in response to 1,3-DNB. However, the lesion seen in synchronized animals was more severe and less stage specific than that seen in weight-matched, unsynchronized animals. This increase in degree of susceptibility could be partially explained by differences in toxicokinetics. Stage-synchronized testes could provide unique insights into stage-specific cellular and molecular events, especially for in vitro studies where the stage enrichment could be maximally exploited. However, results obtained from in vivo toxicity studies using animals subjected to VADR should be interpreted carefully in light of the confounding physiologic/metabolic perturbations potentially induced by the VADR procedure. 相似文献
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A deletion mutant of the catalytic RNA component of Escherichia coli RNase P missing residues 87-241 retains the ability to interact with the protein component to form a functional catalyst. The deletion of this phylogenetically conserved region significantly increases the Km, indicating that the deleted structures may be important for binding to the precursor tRNA substrate but not for the cleavage reaction. Under some reaction conditions, this RNase P deletion mutant can become a relatively non-specific nuclease, indicating that this RNA's catalytic center may be more exposed. The catalytic core of the RNase P is formed by less than one third of the 377 residues of the RNase P RNA. 相似文献
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