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We provide causal evidence that regulation induced product shocks significantly impact aggregate demand and firm performance in pharmaceutical markets. Event study results suggest an average loss between $569 million and $882 million. Affected products lose, on average, $186 million over their remaining effective patent life. This leaves a loss of between $383 million and $696 million attributable to declines in future innovation. Our findings complement research that shows drugs receiving expedited review are more likely to suffer from regulation induced product shocks. Thus, it appears we may be trading off quicker access to drugs today for less innovation tomorrow. Results remain robust to variation across types of relabeling, market sizes, and levels of competition.  相似文献   
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Supplemental reading instruction provides a way to improve the reading outcomes of students at risk for reading difficulties and to meet the challenges produced by increases in student diversity in today’s classrooms. The research–based intervention described in this article includes intensive, explicit, and systematic reading instruction in five areas: fluency, phonemic awareness, instructional–level reading with an emphasis on comprehension, word analysis, and spelling. This intervention was effective in improving the reading skills of low SES, second–grade English monolingual and English–language learners.  相似文献   
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A new set of standards to guide professional development in assessment among student affairs professionals and faculty members is poised to revolutionize how educators learn to conduct this essential work.  相似文献   
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Although little is known about learning disabilities (LDs) in English language learners (ELLs), there is a substantial knowledge base about the identification, assessment, and intervention of and for LDs in monolingual native English‐speaking students. Building on this knowledge, participants at an October 2003 National Symposium on Learning Disabilities in English Language Learners were asked to suggest research questions, priorities, and suggestions on how to build the necessary infrastructure to address critical research needs. In the discussions that took place, important themes emerged: (1) identification and assessment of LD and/or reading disabilities (RD) in ELLs (ELL/Ds), (2) understanding of the language and literacy developmental trajectories of ELLs, (3) understanding of the individual and contextual factors affecting outcomes, (4) the intersection of all of these areas with neurobiology, and (5) developing and testing the effectiveness of interventions for learning disabilities in ELL/Ds. These themes, and the research agenda that was forged around them, are presented. In addition, the practice implications of this agenda are presented, along with some suggestions for current practice while we await future research findings.  相似文献   
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This paper addresses the role that scientific status plays in initial public offerings of technology focused firms. The paper builds on the literature of the sociology of science as well as the work of Spence (1974) and Podolny (1993) and argues that the presence of a Nobel laureate affiliated with a firm making an IPO provides a signal of firm quality to potential investors. Moreover, and building on the work of Podolny and Scott Morton (1999) and Stuart et al. (1999) we hypothesize that the importance of status diminishes as other measures of firm quality become available. We test our hypothesis for two periods of initial public offerings in biotechnology. We document that there is a clear difference in “maturity” of the firms across the two windows on a number of metrics. Consistent with our hypothesis that Nobel laureates play an important role as a non-financial signal of firm quality, we find that first-window firms with a Nobel laureate affiliate realize greater IPO proceeds in the amount of $24 million. In the second window the amount of money raised is not significantly different between Nobel and non-Nobel firms. This finding is consistent with the signaling literature that argues that the importance of a signal is inversely related to the availability of cogent information on firm quality. Consistent with this view, we also find a change between the two windows in the importance of other non-financial metrics used to convey value. Our research is one of the first to examine the dynamic nature of signals. Because we are unable to distinguish the extent to which the reduction in uncertainty at the firm level is correlated with the reduction of uncertainty at the industry level, the question remains as to the extent to which the diminished importance of signals in our second period is due to a change in market uncertainty versus a change in firm uncertainty.  相似文献   
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Education and Information Technologies - Online collaborative learning (OCL) has received significant attention, but the ultimate goal of adopting OCL is neglected, especially in higher education...  相似文献   
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