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51.
The geography of opportunity: spatial heterogeneity in founding rates and the performance of biotechnology firms 总被引:3,自引:0,他引:3
One of the most commonly observed features of the organization of markets is that similar business enterprises cluster in physical space. In this paper, we develop an explanation for firm co-location in high-technology industries that draws upon a relational account of new venture creation. We argue that industries cluster because entrepreneurs find it difficult to leverage the social ties necessary to mobilize essential resources when they reside far from those resources. Therefore, opportunities for high tech entrepreneurship mirror the distribution of critical resources. The same factors that enable high tech entrepreneurship, however, do not necessary promote firm performance. In the empirical analyses, we investigate the effects of geographic proximity to established biotechnology firms, sources of biotechnology expertise (highly-skilled labor), and venture capitalists on the location-specific founding rates and performance of biotechnology firms. The paper finds that the local conditions that promote new venture creation differ from those that maximize the performance of recently established companies. 相似文献
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AllynJackson 《学会》2003,(12):30-32
20 0 2国际数学家大会 (ICM ) ,于 2 0 0 2年 8月2 0 - 2 8日在中国北京举行。这次大会充满了“第一” :ICM第一次在一个发展中国家举行 ;第一次有举办国的最高领导人出席ICM的开幕式 ;许多出席大会的数学家是第一次来到中国 ;即使对那些以前曾来过中国的与会者 ,由于这个国家近年来的巨大变化 ,他们也觉得是到了一个新地方。中国的组织者的友好和热情 ,不仅反映了这个国家历史悠久的对学问和知识的尊重 ,也说明了他们已认识到加强中国的科学研究能力 ,对国家未来的发展有举足轻重的作用。“这是一次非常特别的ICM ,确实是绝无仅有的”… 相似文献
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Jacqueline Leonard Joy Barnes-Johnson Scott Jackson Dantley Charles Kimber 《The Urban Review》2011,43(1):124-150
This paper reports on a study of elementary preservice teachers’ inquiry-based practices, their efficacy beliefs, and the
role beliefs had on two preservice teachers’ practices in urban classrooms. Results show inquiry-based practices can be cultivated
through field-based experiences and preservice teachers’ efficacy beliefs, as it relates to practice in urban settings, are
malleable. Specifically, personal efficacy beliefs about teaching science improved or were sustained for one cohort of preservice
teachers. However, beliefs about students’ ability to learn science, that is outcome beliefs, were less stable. The results
of two case studies show that science content knowledge was a factor in preservice teachers’ inquiry-based practices. However,
why preservice teachers’ beliefs about student learning declined is less clear. More research is needed, along with follow-up
data on teacher induction, to learn how preservice teachers’ beliefs impact urban students’ science education. 相似文献
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For decades, the HIV epidemic has exacted an enormous toll worldwide. However, trend analyses have discerned significant declines in the overall prevalence of HIV over the last two decades. More recently, advances in biomedical, behavioural, and structural interventions offer considerable promise in the battle against generalised epidemics. Despite advances in the prevention of transmission and new infections, morbidity and mortality of HIV among young people remains a considerable concern for individuals, couples, families, communities, practitioners, and policy-makers around the globe. To accelerate the end of the global HIV epidemic among young people, we must merge existing efficacious interventions with more novel, cost-effective implementation strategies to develop integrated, multi-level combination interventions. The benefits of conceptualising the HIV epidemic more broadly and adopting ecological frameworks for the development of HIV prevention programmes are critical. 相似文献
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Decision-making is a complex process that is largely studied from an experimental perspective or in specific organizational contexts. As such, no generalizable framework exists with which to study decision-making from an individual differences perspective for predictive/selection purposes. By generalising a context-specific decision model proposed by Koriat and Goldsmith (1996), the focus of this research was to therefore test a novel framework for studying individual differences in decision-making tendencies. Utilising this framework within a fictitious Medical Decision-Making Test (MDMT) yielded five novel variables that provided unique insight into individuals’ decision tendencies: Optimal, Realistic, Incompetent, Hesitant and Congruent. Metacognitive confidence and its calibration (bias and CAQ) were used as predictor variables to validate this framework. One hundred ninety-three undergraduate students completed the MDMT and three cognitive ability tests with confidence ratings, a personality questionnaire, and the Need for Closure questionnaire. All decision tendency variables demonstrated excellent internal consistency and were predicted by the metacognitive variables incrementally to the remaining variables as hypothesized. Additionally, the metacognitive indices were found to generalize across the decision-making and cognitive tests. The results imply that this novel framework and MDMT reliably capture individuals’ decision behaviour that shares a meaningful relationship with their general confidence and calibration. 相似文献
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Robert Craig's constitutive meta-model of communication reminds us that while communication scholarship may feel like discovery of communication's natural properties, it is also often (if not always) on a path to invention of new possibilities and reconstitution. The constitutive meta-model suggests that every theory of communication is also a design language for communication, and that design itself may be a path to theory development. Design inquiry can be conducted in all subdisciplines of communication, incorporating and contributing to widely disparate communication theories. Design work itself takes many forms, producing artifacts as diverse as individual messages, persuasive campaigns, interaction protocols, large-scale participation frameworks for public decision-making, and more. This special issue explores design scholarship in the field of communication, with five original essays representing different subfields and different theoretical approaches. In this introduction, we argue that design work is more than application of theory; design itself is a theory-building enterprise. It is a distinct form of inquiry that builds new knowledge, complementary to, but different in kind from, empirical and critical scholarship. 相似文献