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The functional reanimation of paralyzed limbs has been a longstanding goal of neural prosthetic research, but clinically successful applications have been elusive. Natural voluntary limb movement requires four major elements: actuators (i.e., motor units), sensors (i.e., somatosensory afferents), commands (i.e., cerebral cortical activity), and control (i.e., integration of the previous three elements at various levels of the neuraxis). Prosthetic equivalents of each of these elements are, as yet, primitive and often cumbersome to deploy, but new technologies promise substantial improvements for all. This article focuses on one such technology, bionic neuon (BION) modular microimplants, and its relationship to alternative and complementary technologies. The challenge remains to select and integrate them into systems that can be tailored efficiently to the widely disparate needs of patients with various patterns of weakness and paralysis. 相似文献
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Gerald Leach 《Energy Policy》1991,19(10):918-925
The UK differs from may other industrialized nations in that its carbon dioxide (CO2) emissions from energy use have declined in recent years despite relatively rapid economic growth. In all sectors but transport, substantial reductions have already occurred in the level of carbon emissions per unit of GDP output. At the same time, a number of official and unofficial studies have pointed out that the UK has one of the largest remaining potentials amongst comparable industrialized countries for achieving further CO2 reductions through the implementation of cost-effective energy efficiency and fuel switching measures. This paper discusses past and present patterns of energy use and carbons emissions in the UK. The analysis then examines historical trends in UK energy policy and presents policy options for further reducing the UK's energy-use and carbon emissions in the future. 相似文献
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Allen Daniel N.; Strauss Gregory P.; Kemtes Karen A.; Goldstein Gerald 《Canadian Metallurgical Quarterly》2007,21(6):713
Hemispheric involvement in reasoning abilities has been debated for some time, and it remains unclear whether the right hemisphere's involvement in problem solving is modality specific or dependent on the type of spatial reasoning required. In the current study, 2 types of nonverbal reasoning abilities were examined, spatial reasoning and proportional reasoning, in 109 patients with cerebrovascular disease that was confined to either the right or the left hemisphere or was diffuse in nature. Results indicated that no lateralizing effects were present based on type of spatial reasoning. Findings are consistent with the suggestion that higher order cognitive processes involved in nonverbal abstraction and problem solving are not strongly lateralized to the right hemisphere but rather are more generally distributed throughout the cortex. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The effects of age stereotyping on subjects' ratings of interviewee potential were investigated using a simulated auditory interview. Male and female participants (N?=?156) listened to a 12-min interview of a supervisory candidate applying for a temporary position in industry and then rated the interviewee's qualifications for the supervisory position. Participants gave higher overall interview ratings to a younger interviewee even though he had the same qualifications as an older interviewee. Ratings given to the older interviewee, however, were not significantly different from those given to an interviewee whose age was not designated. The findings are discussed in terms of the influence of both positive and negative age stereotypes on ratings of applicant potential. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Comments on the article by S. T. Fiske et al (see record 1992-07509-001) praising the American Psychological Association's (APA's) amicus brief intended to inform the Supreme Court of current scientific thinking regarding gender stereotyping. A balanced perspective, it is argued, should include both research supporting an argument and findings that are inconsistent with that argument. The APA brief gave no indication of contradictory findings. Moreover, review of the research cited indicates that more than half of the studies do not support the argument for which they were cited. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Gerald Foley 《Utilities Policy》1992,2(4)
The institutional aspects of rural electrification programmes are often given much less attention than their importance warrants. In a number of important ways, rural electrification is in conflia with the primary concerns of the utilities mandated to implement it. Resolving this dilemma requires a separation of functions, with the agency responsible for rural electrification being given substantial autonomy. The range of institutional options for achieving this is wide and the choice should be tailored to the local context ana programme objectives. 相似文献
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Matthews Gerald; Jones Dylan M.; Chamberlain A. Graham 《Canadian Metallurgical Quarterly》1992,77(4):406
Personality and cognitive predictors of mail coding were investigated in 2 samples, 1 of high coding ability (N?=?56) and 1 of mixed ability (N?=?158). Two approaches to predicting correlates of skill within groups of differing ability were compared: P. L. Ackerman's (1988) ability theory and D. A. Norman and T. Shallice's (1985) account of levels of action control. The predictors of mail-coding skill varied with ability: Personality variables were more predictive among higher ability Ss, and cognitive measures were more predictive among lower ability Ss. Implications of the findings for theories of individual differences in skill are discussed. There were 2 main practical conclusions. First, the measures used were more predictive than a standard psychometric selection test. Second, correlates of skill may be different among unselected job applicants and among the subset of applicants hired for subsequent operational training. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献