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51.
52.
David P. Colvin 《The Journal of Technology Transfer》1995,20(2):5-7
Historically, small businesses have been the innovation engine of the United States, with significantly more than half of the new technologies and products coming from small enterprises. In 1992, there were more than 21 million small businesses with fewer than 500 employees each in the United States, including 4.5 million small corporations, 1.6 million partnerships, and 15.1 million sole proprietorships. Although most small businesses have considerably fewer than 100 employees, they employ more than half the private U.S. work force, contribute more than half of all sales in the country, and are responsible for over half of the private sector's products. From 1976 to 1990, small firms also generated 65% of the net new jobs. From 1988 to 1990, all of the net new jobs in the U.S. economy were created by small firms. Indeed, small business is really big business in the United States. 相似文献
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Netherlands International Law Review - 相似文献
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This introduction presents the core concepts that shape this special issue on the impact of violence and the processes of development in Central and South America. The understanding of development is considered in terms broader than the economic context alone, in order to assess wider social and political aspects. With a similarly expansive scope, forms of violence are addressed that range from direct physical harm and bodily attack to the often more subtle aggression of racialised abuse or the pressures on community-centred production from dominant market forces. In these contexts, violence, economic initiatives, and political allegiances form unintended and often dangerous networks of consequence for development matters. All the articles in this volume exemplify further the spatial environments of violence and diverse ‘landscapes of fear’ that shape our existence and help to define our actions, territories, and understanding of what happens around us. 相似文献
56.
Sixteen major evaluations of programs to prevent school bullying, conducted in 11 different countries, are reviewed in detail. Of these 16 evaluations, 8 produced desirable results, 2 produced mixed results, 4 produced small or negligible effects, and 2 produced undesirable results. These varying findings may reflect variations in programs, in implementation, in assessment methods, or in evaluation designs. It is concluded that high-quality evaluations are needed in the future, with randomized designs, theoretically grounded interventions, multiple measures of bullying, and attempts to disentangle the effectiveness of different program components. 相似文献
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The impact of high temperatures (24 to 39 degrees C) and low to moderately high humidities (20 to 70%) on the applicability of TLC systems for drug identification was studied during a 6 month climatologic cycle in Burkina Faso (West Africa). In general, the Rf values as observed on the plates were found to be substantially affected as compared with values obtained at temperate climates. Some TLC systems were more affected than others and the largest deviations of up to 30 Rf units were at low humidities. Tropical conditions also had a negative effect on the reproducibility of Rf values. However, when an Rf-correction procedure was applied, using reference mixtures of known drugs on each plate, accuracy as well as reproducibility of the resulting Rfc values were drastically improved and data thus corrected were found to be compatible with existing TLC data bases developed under moderate climatological conditions. The impact of high to extremely high humidities (70 to 100%) remains to be investigated. 相似文献
59.
Veto Players and Civil War Duration 总被引:1,自引:0,他引:1
David E. Cunningham 《American journal of political science》2006,50(4):875-892
Civil wars show a remarkable variation in how long they last. Some end within days; others continue for decades. What explains the extreme intractability of some wars while others are resolved quickly? This article argues that conflicts with multiple actors who must approve a settlement (veto players) are longer because there are fewer acceptable agreements, information asymmetries are more acute, and shifting alliances and incentives to hold out make negotiation more difficult. This veto player approach to explaining variation in civil war duration is tested using a new dataset containing monthly data on all parties to each civil war begun since World War II. The statistical analysis shows a strong correlation between the number of veto players and the duration of civil war. 相似文献
60.
测定了痢疾杆菌福氏 2a 30 1株与喹喏酮类药物耐药性相关的 gyrA基因和 parC基因的序列 ,并对其环丙沙星耐药诱变株的 gyrA和 parC基因喹喏酮类药物耐药性决定区 (QRDR)序列进行了测定分析。结果表明 ,痢疾杆菌福氏 2a 30 1株 gyrA和 parC基因分别为 2 6 2 5bp和2 2 5 6bp ,环丙沙星诱导的耐药菌 gyrA基因QRDR(2 4 5bp)发生氨基酸残基 6 9 Ala→Val和 87 Tyr→Asp改变 ,parC基因QRDR(2 37b)发生氨基酸残基 79 Ala→Asp、84 Ala→Glu和 85 Pro→Ala改变。这一研究结果对认识痢疾杆菌喹喏酮类药物耐药性的分子机理具有重要意义 相似文献