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281.
Although our study was conducted in only one physical science discipline, and although most of the individual tests did not yield statistically significant differences, the data consistently yielded a trend in the direction of the existence of discrimination against women in academia. This leads us to the tentative conclusion that when two equally qualified applicants are being considered for an academic position, a male would be chosen over a female. However, a woman with clearly superior qualifications, in competition with an average man, is likely to be recognized. The bias seems to hold especially for higher-quality schools, in departments with younger and newer chairmen, and for chairmen from schools located in the eastern and western parts of the country. The underutilization of potentially qualified women in science represents lost opportunities to society and to science in terms of the overall goal of advancing science. To the extent that the bias reflects strongly held cultural norms, change will come slowly. However, structural changes within the institutions that employ and train women scientists may be achieved sooner through the active intervention of outside agencies, for example, the enforcement by the Department of Health, Education, and Welfare of the Equal Opportunities Act in colleges and universities (19). In addition, such federal grant-awarding agencies as the National Science Foundation and the National Institutes of Health could be given a mandate to make a special effort to identify and award grants and other forms of recognition to deserving women scientist.  相似文献   
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The surprising genetics of bottlenecked flies   总被引:1,自引:0,他引:1  
R Lewin 《Science (New York, N.Y.)》1987,235(4794):1325-1327
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Root, stem and leaf tissues, from cotton plants exposed to CO2 at ambient (370 μmol mol−1 (control)) or elevated (550 μmol mol−1 (FACE; free-air carbon dioxide enrichment)) levels in the field during the 1990 and 1991 growing seasons, were analyzed for nonstructural carbohydrates (glucose, fructose, sucrose and starch). Besides the FACE treatment, these plants were also exposed to two irrigation levels: 100% and 67% replacement of evapotranspiration. FACE had a greater effect upon cotton plant nonstructural carbohydrates than did irrigation treatments. Leaf carbohydrate content was increased by FACE, but this increase was much more pronounced in the stems and roots. Starch and soluble sugars in leaves in FACE plots tended to be consistently greater than in control leaves, without much change in carbohydrate content during the growing season. In contrast, root and stem, starch and soluble sugar pools were strongly increased by FACE and fluctuated strongly during the growing season. In both seasons, stem and taproot nonstructural carbohydrate content passed through a minimum during periods of heavy boll set. The fluctuations in stem and root carbohydrate content were therefore probably caused by the varying metabolic demands of the developing plant. These results suggest that a significant effect of CO2 enrichment on starch-accumulating plants is an increase of nonstructural carbohydrate, especially starch, in nonleaf storage pools. This buildup occurs somewhat independently of the water status of the plant, and these enlarged pools can be drawn upon by the growing plant to maintain growth during periods of high metabolic demand.  相似文献   
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