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This paper addresses the evaluation of real growth forecasts made by impact studies. Intervention analysis is used to estimate the ex post impact of blockbuster exhibits on economic growth in Jackson, Mississippi (chosen because state and local governments provide regular subsidies to finance the exhibitions). Non-farm employment measures real economic growth and dummy variables capture the occurrence of the exhibitions. Univariate time series techniques identify and estimate a stationary process after filtering the data for seasonal and cyclical effects. The analysis estimates the short run impact on Jackson’s filtered employment series due to the blockbuster exhibitions as approximately 700 jobs.  相似文献   
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This paper explores a theoretical and methodological basis for studying foreign immigrants' acculturation processes from a communication perspective. Communication patterns of immigrants are conceptualized on three levels — behavioral, attitudinal, and perceptual. The behavioral level of communication includes the immigrant's participation in communication channels of the host society as well as the ethnic community. The perceptual level refers to the immigrant's cognitive structure in perceiving the host society. The attitudinal level is examined by the immigrant's affective-evaluative orientation toward the host society. The three levels of communication patterns were empirically investigated in a survey of 400 randomly selected Koreans in the Chicago area. The communication variables were assessed through composite scores using questionnaire items that were tested for reliability. The results show an overall linear trend in the immigrant's interethnic communication with Americans, positive attitude toward Americans, cognitive complexity in perceiving the American society, and satisfaction level. A simultaneous increase is observed in the immigrant's interpersonal communication with Americans and with other Koreans. The immigrant's use of ethnic media rapidly decreases over the years while that of American media steadily increases. Findings are discussed in comparison to previous studies of foreign immigrants and students and to sociological theories of acculturation of minority groups.  相似文献   
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This article, which examines variables affecting scores on a test of library skills, finds that the frequency with which students receive assignments requiring library research is the best predictor of a score. The unevenness is students' research skills has implications for bibliographic instruction.  相似文献   
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In this paper, we have presented a non-lithographic embedded template method for rapid and cost-effective fabrication of a selectively permeable calcium-alginate (Ca-alginate) based microfluidic device with long serpentine delay channel. To demonstrate the versatility of the presented method, we have demonstrated two different strategies to fabricate serpentine long delay channels without using any sophisticated microfabrication techniques, in formal lab atmosphere. The procedure presented here, also, enables the preparation of a multilayered microfluidic device with channels of varying dimensions, in a single device without using any sophisticated micromachining instrumentation. In addition, we have also qualitatively studied the diffusion of small and large molecules from a Ca-alginate based microfluidic device and proposed a method to effectively control the out-flow of macro biomolecules from the crosslinked Ca-alginate matrix to create a selectively permeable matrix required for various biological and biomimetic applications, as mentioned in the Introduction section of this work.  相似文献   
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Lee K  Kim C  Young Yang J  Lee H  Ahn B  Xu L  Yoon Kang J  Oh KW 《Biomicrofluidics》2012,6(1):14114-141147
We propose a simple method for forming massive and uniform three-dimensional (3-D) cell spheroids in a multi-level structured microfluidic device by gravitational force. The concept of orienting the device vertically has allowed spheroid formation, long-term perfusion, and retrieval of the cultured spheroids by user-friendly standard pipetting. We have successfully formed, perfused, and retrieved uniform, size-controllable, well-conditioned spheroids of human embryonic kidney 293 cells (HEK 293) in the gravity-oriented microfluidic device. We expect the proposed method will be a useful tool to study in-vitro 3-D cell models for the proliferation, differentiation, and metabolism of embryoid bodies or tumours.  相似文献   
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