排序方式： 共有29条查询结果，搜索用时 15 毫秒
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James V. Devine Luther C. Jones Janice W. Neville Dilys J. Sakai 《Learning & behavior》1977,5(1):57-62
Two experiments were performed to determine the effect of sample duration (0.1, 2, and 4 sec), delay interval (.03, 4, 8, 16, and 32 sec), and type of stimulus (color and shape) on the matching performance of rhesus monkeys. In Experiment 1, the 15 possible delay-duration combinations were randomly presented in blocks of 15 trials. In Experiment 2, each duration was held constant and the five delays randomly presented. Then each delay interval was held constant with the three durations randomly varied. Matching performance increased as sample duration increased (ps < .01 and .005), while length of delay did not significantly affect performance. The type of stimuli paired in the matching test significantly affected performance (ps < .05 and .10) with the shape/shape choices leading to the poorest performance. Stimulus discriminability and amount of training with brief sample durations were implicated as significant determinants of matching performance. 相似文献
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Oxygen and glucose supply is one of the important factors for the growth and viability of the cells in cultivation of tissues, e.g., spheroid, multilayered cells, and three-dimensional tissue construct. In this study, we used finite element methods to simulate the flow profile as well as oxygen and glucose supply to the multilayered cells in a microwell array chip for static and perfusion cultures. The simulation results indicated that oxygen supply is more crucial than glucose supply in both static and perfusion cultures, and that the oxygen supply through the wall of the perfusion culture chip is important in perfusion cultures. Glucose concentrations decline with time in static cultures, whereas they can be maintained at a constant level over time in perfusion cultures. The simulation of perfusion cultures indicated that the important parameters for glucose supply are the flow rate of the perfusion medium and the length of the cell culture chamber. In a perfusion culture chip made of oxygen-permeable materials, e.g., polydimethylsiloxane, oxygen is hardly supplied via the perfusion medium, but mainly supplied through the walls of the perfusion culture chip. The simulation of perfusion cultures indicated that the important parameters for oxygen supply are the thickness of the flow channel and the oxygen permeability of the walls of the channel, i.e., the type of material and the thickness of the wall. 相似文献
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Qinglei Wang Yanan Qian Ruihua Song Zhicheng Dou Fan Zhang Tetsuya Sakai Qinghua Zheng 《Information Retrieval》2013,16(4):484-503
Web search queries are often ambiguous or faceted, and the task of identifying the major underlying senses and facets of queries has received much attention in recent years. We refer to this task as query subtopic mining. In this paper, we propose to use surrounding text of query terms in top retrieved documents to mine subtopics and rank them. We first extract text fragments containing query terms from different parts of documents. Then we group similar text fragments into clusters and generate a readable subtopic for each cluster. Based on the cluster and the language model trained from a query log, we calculate three features and combine them into a relevance score for each subtopic. Subtopics are finally ranked by balancing relevance and novelty. Our evaluation experiments with the NTCIR-9 INTENT Chinese Subtopic Mining test collection show that our method significantly outperforms a query log based method proposed by Radlinski et al. (2010) and a search result clustering based method proposed by Zeng et al. (2004) in terms of precision, I-rec, D-nDCG and D#-nDCG, the official evaluation metrics used at the NTCIR-9 INTENT task. Moreover, our generated subtopics are significantly more readable than those generated by the search result clustering method. 相似文献
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Takako Yuki Keiko Mizuno Keiichi Ogawa Sakai Mihoko 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2013,59(1):47-66
Many girls are not sent to school in Yemen, despite basic education being free as well as compulsory for all children aged 6–15. Aiming to improve girls’ enrolment by increasing parental and community involvement, the Japan International Cooperation Agency (JICA) offered a technical cooperation project in June 2005 called Broadening Regional Initiative for Developing Girls’ Education (BRIDGE). Phase 1 of this project ran for three and a half years, piloting a participatory school management model supported by school grants in six districts of the Taiz Governorate in the Southwest of Yemen. To find out how successful this approach has been in a traditional society, the authors of this paper analysed the gender parity index (GPI) of the project’s pilot schools. Based on data collected at three points in time (in the initial and final years of the project, and two years after the project’s end), their findings suggest that interventions in school management which strongly emphasise girls’ education can be effective in improving gender parity rather quickly, regardless of the schools’ initial conditions. However, the authors also observe that the pilot schools’ post-project performance in terms of gender parity is mixed. While the local government allocated budgets for school grants to all pilot schools even after the project’s end, training and monitoring activities were cut back. The authors further observe that the variation in performance appears to be significantly correlated with school leaders’ initial perceptions of gender equality and with the number of female teachers employed. These findings point to the importance of providing schools with continuous long-term guidance and of monitoring those which implement school improvement programmes. 相似文献
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In this study, we propose a microfluidic cell culture device mimicking the microscopic structure in liver tissue called hepatic cords. The cell culture area of the device was designed to align hepatocytes in two lines in a similar way to hepatic cords. Thanks to the structural design together with a cell seeding procedure, rat primary hepatocytes were successfully aligned in two lines and cultured under perfusion condition. It is shown that aligned hepatocytes gradually self-organize and form bile canaliculi along the hepatic cord-like structure. The present technique to culture hepatocytes with functional bile canaliculi could be used as an alternative to animal testing in the field of drug discovery and toxicological studies, and also be beneficial to tissue engineering applications. 相似文献
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Counseling development models have many of the same purposes and address many of the same phenomena as the cognitive science models of expertise. But these two model types have been developed independently and each has drawn only minimally from the other. The purpose of this article is to point out some of the similarities and differences between the model types. 相似文献
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Hiroaki Takehara Akira Nagaoka Jun Noguchi Takanori Akagi Takamasa Sakai Ung-il Chung Haruo Kasai Takanori Ichiki 《Biomicrofluidics》2013,7(5)
Hydrogels have several excellent characteristics suitable for biomedical use such as softness, biological inertness and solute permeability. Hence, integrating hydrogels into microfluidic devices is a promising approach for providing additional functions such as biocompatibility and porosity, to microfluidic devices. However, the poor mechanical strength of hydrogels has severely limited device design and fabrication. A tetra-poly(ethylene glycol) (tetra-PEG) hydrogel synthesized recently has high mechanical strength and is expected to overcome such a limitation. In this research, we have comprehensively studied the implementation of tetra-PEG gel into microfluidic device technology. First, the fabrication of tetra-PEG gel/PDMS hybrid microchannels was established by developing a simple and robust bonding technique. Second, some fundamental features of tetra-PEG gel/PDMS hybrid microchannels, particularly fluid flow and mass transfer, were studied. Finally, to demonstrate the unique application of tetra-PEG-gel-integrated microfluidic devices, the generation of patterned chemical modulation with the maximum concentration gradient: 10% per 20 μm in a hydrogel was performed. The techniques developed in this study are expected to provide fundamental and beneficial methods of developing various microfluidic devices for life science and biomedical applications. 相似文献