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991.
992.
A simple language called Swarm is used as a vehicle for the investigation of the shared dataspace approach to concurrent computation. An important feature of Swarm is its ability to bring a variety of programming paradigms under a single, unified model. In a series of related examples Swarm's capacity to express shared-variable, message-passing, and rule-based computations; to specify synchronous and asynchronous processing modes; and to accommodate highly dynamic program and data structure is explored. Several illustrations make use of a programming construct unique to Swarm, the synchrony relation and explain how this feature can be used to construct dynamically structured, partially synchronous computations. An overview of the Swarm programming notation, an examination of Swarm programming strategies via a series of related example programs, and a discussion of the distinctive features of the shared dataspace model are given. A formal operational model for Swarm is presented  相似文献   
993.
This study used a genetic correlational strategy to characterize the neurobiological basis of ethanol's (0, 2, or 4 g/kg) aversive effects as indexed by conditioned taste aversion. Substantial strain differences in taste aversion and hypothermia were observed, but the genetic correlation between these phenotypes was not significant. However, significant genetic correlations were observed between taste aversion and ethanol-related behaviors measured in previous studies, including home-cage ethanol preference (r = .68) and ethanol withdrawal severity (r = -.69). Strains showing stronger taste aversion tended to show lower ethanol preference and higher withdrawal severity. This pattern of findings is consistent with previous studies suggesting a commonality in neurobiological mechanisms underlying these phenotypes. These results do not support the hypothesis that ethanol-induced taste aversion is mediated by the drug's rewarding properties. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
994.
Proactive personality was expected to moderate the relationship between controllable work and nonwork stressors (e.g., time-based work-family interference) and job/life satisfaction. Moderated multiple regression analyses of survey data from a sample of professionals (N=133) revealed a significant interaction between time-based family interfering-with work and proactive personality predicting life satisfaction and several main effects offering partial support for the hypothesized relationships (α  相似文献   
995.
新一代移动系统的设计出发点主要在于通过将无线收发、坚固耐用、结构紧凑的读取器安装在车辆和其他便携设备上,在最大范围内增加RFID的作用距离。 这一设计的效果非常明显,就像是一个数据“强光灯”照亮了分销流程的每一个角落,提高了精确度,实现了更加智能化的资产管理及更加明智的决策和更高的工作效率。  相似文献   
996.
997.
Cunningham  R. J.  Dick  A. J. J. 《Acta Informatica》1985,22(2):149-169
Summary Re-writing systems for partial algebras are developed by modifying the Knuth-Bendix completion algorithm to permit the use of latticestructured domains. Some problems with the original algorithm, such as the treatment of division rings, are overcome conveniently by this means. The use of a type lattice also gives a natural framework for specifying data types in Computer Science without over-specifying error situations. The soundness and meaning of the major concepts involved in re-writing systems are reviewed when applied to such structures.  相似文献   
998.
Adverse influence of cigarette smoking on the endothelium   总被引:2,自引:0,他引:2  
The effect of smoking on the blood vessel intima was examined by comparing indices of endothelial activity in serum from smokers with that from non-smokers. Serum from smokers contained higher levels of von Willebrand factor (p < 0.01), the smoking markers cotinine (p < 0.02) and thiocyanate (p < 0.01), and was more cytotoxic to endothelial cells in vitro (p < 0.02) than serum from non-smokers. The acute effects of smoking two unfiltered medium tar cigarettes was to briefly increase von Willebrand factor (p < 0.001) and cytotoxicity of serum to endothelial cells in vitro (p < 0.005), but lipid peroxides or thiocyanate were not increased by this short exposure to tobacco smoke. Although there were correlations between von Willebrand factor and smokers consumption of cigarettes (r = 0.28, p < 0.02), number of years smoking (r = 0.41, p < 0.001) and cotinine (r = 0.45, p < 0.01), the tissue culture of endothelial cells with physiological levels of thiocyanate or nicotine suggested that these two smoking markers were not cytotoxic. They are therefore unlikely to be directly responsible for increased von Willebrand factor in the serum of smokers. We suggest that smoking exerts a deleterious influence on the endothelium and that the mechanism is complex.  相似文献   
999.
An unusual case of cervicofacial actinomycosis presenting as acute upper airway obstruction and demanding urgent tracheostomy is reported. Diagnosis was established by microscopic examination of the pus and culture of Actinomyces israelii. Repeated surgical drainage of the purulent foci and prolonged treatment with penicillin obtained resolution of the disease. Clinicians dealing with acute head and neck swellings should always consider actinomycosis as a possible diagnosis.  相似文献   
1000.
Memory for text that required active construction (generation) on the part of the reader to comprehend some of the information was examined. (Letters were deleted from the words composing some of the idea units of the text). For both high school students and older adults, idea units that had letters deleted were remembered better than idea units with intact words on a cued-recall test. This pattern held for easier as well as for harder letter deletions. It was concluded that retention of textually presented information can be improved in older adults if the presentation format of the text induces or guides mental operations that support good encoding. Production-deficiency accounts and attentional/resource deficiency accounts of age-related memory decrements are discussed in light of the present results. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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