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This paper summarizes some of the experimental evidence of the apparent biological effects produced by atmospheric ionization. Thermionic ion sources are discussed and the results of experimental determinations of their characteristics are presented.  相似文献   
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Linguistic influences on networks of professional communication and recognition among engineers at two Quebec universities were examined. It was hypothesized that chemists and engineers affiliated with the French medium University of Montreal and the Ecole Polytechnique would be less active in research and more likely to obtain scientific recognition locally and to feel professionally unrecognized outside Quebec compared to their colleagues at McGill University. The findings suggest that the localizing effects of using a medium of scientific training which is not the predominant language of international scientific communication and recognition (French) are ambiguous. Although chemists and engineers at the French medium institutions were less active researchers, their language of professional communication with other scientific communities was English and there was little sense of isolation.This research has been supported by grants from the Canadian Council and the Ecole Polytechnique of Montreal. The authors also wish to thank Miss Madeleine Palmer, Miss Daniella Quiniou and Miss Rosalba Casas for their help in data collection for this paper.  相似文献   
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Black and white male schoolchildren covertly evaluated their own performance at a verbal task administered by black and white male experimenters. It was hypothesized that academically successful children would be predisposed to appraise themselves favorably, whereas relatively unsuccessful pupils would be biased toward self-criticism. The covert self-evaluations were assumed to represent at internalization of early experiences of predominantly positive or negative social reinforcement from adult socializing agents. The predicition for self-criticism was upheld in the white experimenter condition but not in the black experimenter condition. Relationships consistent with the theory were found between subjects' self-appraisals and their retrospective reports of positive and negative reinforcements received from parents and teachers in various typical situations. These relationships were more evident for black subjects than for white subjects. The extent to which children's self-praise and self-criticism mediated affect was assessed by means of a color conditioning technique. Contrary to predicition, possibly due to the easy nature of the experimental task.  相似文献   
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The classical criteria for controllability and observability are given a tensorial formulation which is then extended into Boolean form directly related to a digraph interpretation of system structure. This is examined in detail with particular reference to group theoretic aspects, invariant properties under transformation, the term rank test and the existence of zero eigenvalues.Within this framework the structural design concepts of potential controllability and observability are presented in generalised terms.  相似文献   
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