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191.
Cell fusion consists of inducing the formation of a hybridoma cell containing the genetic properties of the progenitor cells. Such an operation is usually performed chemically or electrically. The latter method, named electrofusion, is considered as having a strong potential, due to its efficiency and non-toxicity, but deserves further investigations prior to being applicable for key applications like antibody production and cancer immunotherapy. Indeed, to envision such applications, a high amount of hybrid cells is needed. In this context, we present in this paper a device for massive cell pairing and electrofusion, using a microarray of non-connected conductive pads. The electrofusion chamber––or channel––exposes cells to an inhomogeneous electric field, caused by the pads array, enabling the trapping and pairing of cells with dielectrophoresis (DEP) forces prior to electrofusion. Compared to a mechanical trapping, such electric trapping is fully reversible (on/off handling). The DEP force is contactless and thus eases the release of the produced hybridoma. Moreover, the absence of wire connections on the pads permits the high density trapping and electrofusion of cells. In this paper, the electric field mapping, the effect of metallic pads thickness, and the transmembrane potential of cells are studied based on a numerical model to optimize the device. Electric calculations and experiments were conducted to evaluate the trapping force. The structure was finally validated for cell pairing and electrofusion of arrays of cells. We believe that our approach of fully electric trapping with a simple structure is a promising method for massive production of electrofused hybridoma.  相似文献   
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A comparison of institutional enrollment data and counseling center service utilization data at 66 universities showed that neither ethnic minority students nor European American students under‐ or overutilized counseling services (Study 1). Data from Study 2 examining students in the general campus bodies at 45 institutions indicated that utilization of counseling center services for students of various ethnicities was predicted by the ethnic composition of the counseling center staff. Among students of color, utilization of campus counseling services was predicted by greater psychological distress, less family support, and a history of previous psychological problems.  相似文献   
193.
Conclusion Primary teachers will continue to be confronted with topics about which they themselves may not share the understandings of experts in the area. They are surely not alone there. Secondary and tertiary science teachers who have more extensive backgrounds find themselves in the same situation. Increasing the number of areas in which primary teachers share the understandings of scientists would be of value. However the data of this study suggest that it would also be worthwhile to focus attention on the strategies and understandings they may use to increase their familiarity with scientist's understandings of natural phenomena. The Interactive Teaching Approach (Biddulph and Osborne, 1984) offers an appropriate model for such activity.  相似文献   
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Despite rapid growth of the biotechnology industry worldwide, a number of public concerns about the application of biotechnology and its regulation remain. In response to these concerns, greater emphasis has been placed on promoting biotechnologists’ public engagement. As tertiary science degree programmes form the foundation of the biotechnology sector by providing a pipeline of university graduates entering into the profession, it has been proposed that formal science communication training be introduced at this early stage of career development. The aim of the present study was to examine the views of biotechnology students towards science communication and science communication training. Using an Australian biotechnology degree programme as a case study, 69 undergraduates from all three years of the programme were administered a questionnaire that asked them to rank the importance of 12 components of a biotechnology curriculum, including two science communication items. The results were compared to the responses of 274 students enrolled in other science programmes. Additional questions were provided to the second year biotechnology undergraduates and semi‐structured interviews were undertaken with 13 of these students to further examine their views of this area. The results of this study suggest that the biotechnology students surveyed do not value communication with non‐scientists nor science communication training. The implications of these findings for the reform of undergraduate biotechnology courses yet to integrate science communication training into their science curriculum are discussed.  相似文献   
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This paper analyses the outcome of a reform of the academic career structure in Norway. From 1993 on, associate professors can apply for promotion to full professorships on the basis of individual research competence irrespective of vacant professorships. This has now become a more important way of attaining a full professorship than through competition with other applicants. Only 30% of new professors are appointed the traditional way. The reform has led to a substantial increase in the number of full professors in the university sector, from 37% of the tenured academic staff in 1991 to 47% in 2001.  相似文献   
197.
A letter-search task was used to test the hypothesis that affixes are chunked during morphological processing and that such chunking might operate differently for prefixes and suffixes. Participants had to detect a letter target that was embedded either in a prefix or suffix (e.g., ‘R’ in propoint or filmure) or in a non-prefix beginning or non-suffix ending (e.g., ‘R’ in cropoint or filmire). Prefixed and suffixed letter-strings comprised real stems and affixes but never formed a real word. Effects of letter cluster frequency were also investigated by manipulating the frequency of non-affix beginnings and endings. Letter search took longer in suffixes compared with non-suffix endings but not for prefixes compared with non-prefix beginnings. Moreover, performance was not affected by letter cluster frequency. We interpret our findings in the light of recent accounts of morpho-orthographic segmentation and the different function of prefixes and suffixes.  相似文献   
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After Phnom Penh was liberated from the Khmer Rouge in 1979, health science education in Cambodia had to be completely rebuilt. In this article, the authors report the results of a teaching collaboration between the University of Melbourne (Australia), the International University (Cambodia), and the University of Health Sciences (Cambodia). The main objectives in this collaboration were to provide the opportunity for dental and medical students in Cambodia to attend resourced anatomy workshops and to provide an opportunity for anatomy teachers in Cambodia to gain experience in implementing anatomy workshops of the style that are routinely used in the medical and dental curricula at the University of Melbourne. Experienced anatomy educators from the Department of Anatomy and Cell Biology, University of Melbourne, designed and resourced a series of workshops and then delivered these in collaboration with Cambodian teaching staff in Phnom Penh. The Cambodian students who participated in the workshops were incredibly engaged and enthusiastic. The students' evaluations (by questionnaire) indicated a very positive response to the workshops. All of the workshop resources were donated to the two universities so that the staff could continue to implement similar workshops, and plans were developed to continue our collaboration by developing more resourced workshops for this purpose in the future. Two staff members from Cambodia will travel to Melbourne to participate in anatomy workshops and dissection classes at the University of Melbourne. We hope that this extension of the collaboration provides further support and impetus for the development of anatomy education in Cambodia in the future.  相似文献   
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