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The gender composition of faculty is an important issue on many campuses. Substantial efforts are taken by colleges to hire a diverse faculty where women are equitably represented. Several papers suggest that female faculty can act as role models for female students. This issue is particularly emphasized in science and engineering programs. However, empirical research finds mixed support for this hypothesis. We provide a new test of this issue by examining whether female students have higher first-year retention rates when a greater percentage of their classes are taught by female faculty. There is a positive relationship between retention of female students and the percentage of their science and mathematics classes taught by female faculty. Also faculty gender has a greater impact on female students when their classes have few female students. Thus this study provides support for gender-based programs for hiring. 相似文献
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The American Physical Society (APS) has been a leader in using markup languages for publishing. ViewPlus has led development of innovative technologies for graphical information accessibility by people with print disabilities. APS, ViewPlus, and other collaborators in the Enhanced Reading Project are working together to develop the necessary technology and infrastructure for APS to publish its journals in the DAISY (Digital Accessible Information SYstem) eXtended Markup Language (XML) format, in which all text, math, and figures would be accessible to people who are blind or have other print disabilities. The first APS DAISY XML publications are targeted for late 2010. 相似文献
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The authors examined internalizing behavior problems at middle childhood, adolescence, and young adulthood and brain-based measures of stress vulnerability in 154 right-handed, nonimpaired young adults ( M age = 23 years): 71 (30 males, 41 females) born at extremely low birth weight (ELBW; < 1,000 g) and 83 (35 males, 48 females) controls born at normal birth weight (NBW). Internalizing behavior problems increased from adolescence to young adulthood among ELBW individuals. ELBW adults exhibited greater relative right frontal electroencephalogram activity at rest and more concurrent internalizing behavior problems than NBW controls. Being born at ELBW may have subtle influences on brain–behavior relations even in survivors without major impairments and evidence of these influences may not emerge until young adulthood. 相似文献
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In most communication networks, error probabilities 1?→?0 and 0?→?1 are equally likely to occur. However, in some optical networks, such as local and access networks, this is not the case. In these networks, the number of received photons never exceeds the number of transmitted ones. Hence, if the receiver operates correctly, only 1?→?0 errors can occur. Motivated by this fact, in this paper, we present a class of integer codes capable of correcting burst and random asymmetric (1?→?0) errors within a b-bit byte. Unlike classical codes, the proposed codes are defined over the ring of integers modulo 2b ?1. As a result, they have the potential to be implemented in software without any hardware assist. 相似文献
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Annalisa Caloffi Marco Mariani Federica Rossi Margherita Russo 《Research Policy》2018,47(8):1437-1447
We analyse whether public subsidies supporting collaborative research and development (R&D) projects in small and medium-sized enterprises (SMEs) are able to encourage persistent R&D investment and interorganisational networking more than subsidies supporting individual R&D projects. Adopting a counterfactual approach to policy evaluation, we compare subsidies for collaborative R&D and for individual R&D implemented in the same Italian region in the same period. Our findings suggest that, once public support is no longer available, the two subsidies have different effects on different types of SMEs. If the policymakers’ objective is to increase the number of R&D-performing SMEs over time, they should provide subsidies for collaborative R&D to firms with modest R&D experience. If their objective is to increase the amount of spontaneous R&D investment over time, they should target SMEs with some prior R&D experience, using either subsidy. Finally, if their objective is to induce SMEs to network with external organisations, subsidies for collaborative R&D projects should be preferred to subsidies for individual R&D projects. 相似文献
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Fabio Lucidi Arnaldo Zelli Luca Mallia Caterina Grano Paolo M. Russo Cristiano Violani 《Journal of sports sciences》2013,31(5):447-456
Abstract In this study, we assessed the longitudinal effects of social-cognitive mechanisms on the self-reported use of doping substances and supplements among Italian high school students. In total, 1232 students completed questionnaires measuring various psychological factors hypothesized to influence students' intention to use substances. Three months later, 762 of the students completed the same questionnaires a second time and also reported their use of substances during the time between assessments. Overall, the percentages of students using doping substances (2.1%) or supplements (14.4%) were consistent with values reported in the literature. Analysis of the data showed that adolescents' intention to use doping substances increased with stronger attitudes about doping, stronger beliefs that significant others would approve of their use, a stronger conviction that doping use can be justified, and a lowered capacity to resist situational pressure or personal desires. In turn, stronger intentions and moral disengagement contributed to a greater use of doping substances during the previous 3 months. Doping use was also correlated significantly to supplementation. In conclusion, our results provide novel information about some of the psychological processes possibly regulating adolescents' use of doping substances and supplements. The results also highlight possible areas for future study and intervention, focusing on the prevention of adolescents' substance use. 相似文献
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When induction meets memory: evidence for gradual transition from similarity-based to category-based induction 总被引:3,自引:0,他引:3
The ability to perform induction appears early; however, underlying mechanisms remain unclear. Some argue that early induction is category based, whereas others suggest that early induction is similarity based. Category- and similarity-based induction should result in different memory traces and thus in different memory accuracy. Performing induction resulted in low memory accuracy in adults and 11-year-olds, whereas 5-, and 7-year-olds were highly accurate (Experiment 1). After training to perform category-based induction, 5- and 7-year-olds exhibited patterns of accuracy similar to those of adults (Experiment 2). Furthermore, 7-year-olds, but not 5-year-olds, retained this training over time (Experiment 3). With novel categories, even adults performed similarity-based induction, exhibiting high memory accuracy (Experiment 4). These results suggest a gradual transition from similarity- to category-based induction with familiar categories. 相似文献
40.
The emigration of highly-qualified academics (‘brain drain’) is considered an essential factor in the decline of the human capital of post-Soviet Russia. However, statistics show that the scale of this phenomenon since 2000 was minor. The Russian scientists who went abroad for permanent residence or for a contract job abroad represented no more than 2% of Russian scientists with Candidate or Doctor of Science degrees. Yet, at the same time, the relatively new concept of ‘brain circulation’ gains more popularity. The departure of Russian scientists abroad is not only a threat to the development of domestic science but, paradoxically, also the chance to give additional stimulus to its development. 相似文献