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51.

This study examined determinants of underachievement as perceived by 148 Black fifth‐and sixth‐grade students in an urban school district. Explored were the respective influences of social, psychological, and cultural determinants of underachievement as perceived by Black students in three different academic programs (gifted, above‐average, and average). Students were placed into groups based on profiles of achievement behavior (Types I through V) and compared relative to their perceptions and attitudes. Findings from the statistical analyses (frequency analyses, t‐tests, analyses of variance, and multiple regression) suggest that psychological factors played the greatest role in underachievement or poor achievement motivation, and that underachievement behaviors were noted among all students, irrespective of their academic program. Implications and recommendations are suggested for educators working with gifted, above‐average, and average Black students in urban areas.  相似文献   
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Competence to work in schools is an important dimension of professional competence, although it is often a neglected dimension of teacher development. This article reports a qualitative study that examined student teachers’ learning experiences in initial teacher education (ITE) in relation to competence to work in schools. In-depth interviews were conducted with 12 student teachers on an undergraduate ITE programme in Hong Kong. The findings of the study show that competence to work in schools is characterised by student teachers’ deep contextualised learning. In addition, it offers a deeper understanding of this competence in the ITE context by identifying its three facets, namely understanding of the micro-political realities of schools, social capital building and social strategies. The study provides insights for ITE and schools to support student teachers’ development of their competence to work in schools, including the design of ITE curricula, ITE processes and co-curricular activities in undergraduate studies. Moreover, it suggests the importance of developing schools as growth-fostering and positive micro-political sites for ITE fieldwork and teacher induction.  相似文献   
54.
We present a straightforward and rapid surface acoustic wave (SAW) atomization-based technique for encapsulating proteins into 10 μm order particles composed of a biodegradable polymeric excipient, using bovine serum albumin (BSA) as an exemplar. Scans obtained from confocal microscopy provide qualitative proof of encapsulation and show the fluorescent conjugated protein to be distributed in a relatively uniform manner within the polymer shell. An ELISA assay of the collected particles demonstrates that the BSA survives the atomization, particle formation, and collection process with a yield of approximately 55%. The SAW atomization universally gave particles with a textured morphology, and increasing the frequency and polymer concentration generally gave smaller particles (to 3 μm average) with reduced porosity.  相似文献   
55.
Children with learning disabilities in four types of special education settings were compared in terms of social acceptance, number of friends, quality of relationship with best friends, self‐concept, loneliness, depression, social skills, and problem behaviors. Two of the placements (In‐Class Support and Resource Room) were for children with mild to moderate learning disabilities and involved between 30 and 90 minutes of special education per school day. The other two placements (Inclusion Class and Self‐Contained Special Education Class) were designated for children with severe learning disabilities and involved at least a half‐day of special education. Children in the more inclusive placements had more positive social and emotional functioning. Children receiving In‐Class Support were more accepted by peers, had higher self‐perceptions of mathematics competence, and fewer problem behaviors than children receiving Resource Room Support. Children in Inclusion Classes had more satisfying relationships with their best school friends, were less lonely, and had fewer problem behaviors than children in Self‐Contained Special Education Classes.  相似文献   
56.
Verbal intelligence, English-language skills, personality, and attitude scales were used as predictors of academic performance in 230 male and female arts students at the University of Hong Kong. A series of bivariate, multiple, and canonical correlation analyses were performed. The results showed that verbal intelligence and attitudes, excepting study orientation, were not predictive of performance. English-language skills had the most predictive value, accounting for about 10% of the variance of performance measures. Personality variables failed to predict performance when composite criterion measures (GPAs) were used; however, they proved to be of predictive value when results of individual academic subjects were used as criterion measures. The study points to the importance of using noncomposite criterion measures in prediction and of considering the cultural context of achievement.  相似文献   
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<正> 全国化工院校情报中心站第四届年会于1988年10月17日-21日在武汉化工学院召开。中心站21个成员单位的代表出席了会议。化工部情报所的有关同志参加了会议。湖北省及武汉市图书馆情报界的知名人士、武汉化工学院领导等均到会致词祝贺。年会的主要议程有:一、就高校情报工作的服务方向、情报有偿服务、情报教学等方面的改革进行了广泛的交流和探讨。华东化工学院和青岛化工学院的代表介绍了图书馆实行定编定岗、优化组合、工资包干和情报实行定额承包、面向企业的改革尝试,引起了代表们的极大兴趣和热烈讨论。  相似文献   
59.
This paper describes a method for the quantitative detection of cells expressing BlaC, a β-lactamase naturally expressed by Mycobacterium tuberculosis, intended for the diagnosis of tuberculosis. The method is based on the compartmentalization of bacteria in picoliter droplets at limiting dilutions such that each drop contains one or no cells. The co-encapsulation of a fluorogenic substrate probe for BlaC allows the quantification of bacteria by enumerating the number of fluorescent drops. Quantification of 10 colony forming units per milliliter is demonstrated. Furthermore, the encapsulation of single cell in drops maintains the specificity of the detection scheme even when the concentration of bacteria that do not express BlaC exceeds that expressing BlaC by one million-fold.  相似文献   
60.
Many self-propelled microorganisms are attracted to surfaces. This makes their dynamics in restricted geometries very different from that observed in the bulk. Swimming along walls is beneficial for directing and sorting cells, but may be detrimental if homogeneous populations are desired, such as in counting microchambers. In this work, we characterize the motion of human sperm cells ∼60 μm long, strongly confined to ∼25 μm shallow chambers. We investigate the nature of the cell trajectories between the confining surfaces and their accumulation near the borders. Observed cell trajectories are composed of a succession of quasi-circular and quasi-linear segments. This suggests that the cells follow a path of intermittent trappings near the top and bottom surfaces separated by stretches of quasi-free motion in between the two surfaces, as confirmed by depth resolved confocal microscopy studies. We show that the introduction of artificial petal-shaped corrugation in the lateral boundaries removes the tendency of cells to accumulate near the borders, an effect which we hypothesize may be valuable for microfluidic applications in biomedicine.  相似文献   
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