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51.
Whilst laboratory-on-chip cell separation systems using dielectrophoresis are increasingly reported in the literature, many systems are afflicted by factors which impede “real world” performance, chief among these being cell loss (in dead spaces, attached to glass and tubing surfaces, or sedimentation from flow), and designs with large channel height-to-width ratios (large channel widths, small channel heights) that make the systems difficult to interface with other microfluidic systems. In this paper, we present a scalable structure based on 3D wells with approximately unity height-to-width ratios (based on tubes with electrodes on the sides), which is capable of enriching yeast cell populations whilst ensuring that up to 94.3% of cells processed through the device can be collected in tubes beyond the output.  相似文献   
52.
This article contextualizes the significance of lived experience in relation to personal narratives and learning largely by examining Zainab Salbi’s autobiography Between Two Worlds: Escape from Tyranny: Growing Up in the Shadow of Saddam. Discussing Salbi’s education and personal life as the daughter of Saddam’s private pilot, the article explores the learner’s reluctance to share what Donald Winnicott calls ‘the secret self’. This resistance on the part of the learner complicates the notion of communication as a therapeutic method that educators usually use as the bases for teaching and learning, as explicated by Alice Pitt. In Salbi’s politicized world, she explains how suppressed memory and reluctance to express oneself are tools of survival that ultimately turn into a lifestyle inside and outside the classroom. By employing Winnicott’s metaphor of hide and seek to demonstrate ambivalence in communication, this study explores how Salbi’s experience as a woman with a suppressed personal history can culturally and psychologically be very similar to teachers and students who are reluctant to share their own memories. In effect, this paper examines the implications of suppressed memory and knowledge among reluctant learners for pedagogical practices worldwide.  相似文献   
53.
    
Abstract

Outdoor education is emerging as a compulsory component of the school curriculum in Singapore. As more and more young people are involved in outdoor education programmes, the motivational factors that influence students' participation in outdoor activities is an important area of study. The purpose of this study was to use the self-determination theory framework to examine post course satisfaction level among young adolescents. A total of 314 secondary school students aged from 12 to 16 years took part in the survey. Results showed that external regulation negatively predicted self-reported satisfaction whereas intrinsic motivation positively predicted participants' satisfaction levels of the course. It is highlighted that young adolescents should not be coerced into outdoor education programmes. They should be provided with a meaningful rationale for participation, given some autonomy for decision-making and to have a positive and enjoyable experience during the programme.  相似文献   
54.
This study reviews the higher education movement, and the development of Universities in Jordan. Academic libraries use of Arabized software packages (MINISIS and CDS/ISIS), rationale for selection, applications, services, problems, solutions, and future plans are surveyed. Types of hardware, staff, and material entries are discussed. The study samples included 20 libraries. All of 17 (85%) respondent libraries are computerized. Six (35·3%) use MINISIS, nine (52·9%) use CDS/ISIS, and two (11·8%) use customized packages. Systems are mostly employed in technical processing, reference services, bibliographies, and acquisitions. Adaptability to Arab libraries functions, handling of bi-lingual documents, and networking ability are the prime priority, inter alia , reasons for packages selection. Insufficient funds and equipment, and unskilled staff are the major hindrances which obstruct the full use of packages. This study stresses the need to develop packages conducive to meet particular Arab libraries demands, plans for manpower academic training, and the necessity for libraries linkage to networks.  相似文献   
55.
Chlorella vulgaris (CV) has been reported to have antioxidant and anticancer properties. We evaluated the effect of CV on apoptotic regulator protein expression in liver cancer-induced rats. Male Wistar rats (200∼250 g) were divided into eight groups: control group (normal diet), CDE group (choline deficient diet supplemented with ethionine in drinking water to induce hepatocarcinogenesis), CV groups with three different doses of CV (50, 150, and 300 mg/kg body weight), and CDE groups treated with different doses of CV (50, 150, and 300 mg/kg body weight). Rats were sacrificed at various weeks and liver tissues were embedded in paraffin blocks for immunohistochemistry studies. CV, at increasing doses, decreased the expression of anti-apoptotic protein, Bcl-2, but increased the expression of pro-apoptotic protein, caspase 8, in CDE rats, which was correlated with decreased hepatoctyes proliferation and increased apoptosis as determined by bromodeoxy-uridine (BrdU) labeling and terminal deoxynucleotidyl transferase mediated dUTP nick-end labeling (TUNEL) assay, respectively. Our study shows that CV has definite chemopreventive effect by inducing apoptosis via decreasing the expression of Bcl-2 and increasing the expression of caspase 8 in hepatocarcinogenesis-induced rats. Project supported by Department of Biochemistry, Faculty of Medicine, UKM Medical Center, Universiti Kebangsaan Malaysia, and the Malaysian Ministry of Science and Technological Innovation (MOSTI)  相似文献   
56.
An experimental machine vision apparatus was used to identify and extract recyclable plastic bottles out of a conveyor belt. Color images were taken with a commercially available Webcam, and the recognition was performed by our homemade software, based on the shape and dimensions of object images. The software was able to manage multiple bottles in a single image and was additionally extended to cases involving touching bottles. The identification was fulfilled by comparing the set of measured features with an existing database and meanwhile integrating various recognition techniques such as minimum distance in the feature space, self-organized maps, and neural networks. The recognition system was tested on a set of 50 different bottles and provided so far an accuracy of about 97% on bottle identification. The extraction of the bottles was performed by means of a pneumatic arm, which was activated according to the plastic type; polyethylene-terephthalate (PET) bottles were left on the conveyor belt, while non-PET bottles were extracted. The software was designed to provide the best compromise between reliability and speed for real-time applications in view of the commercialization of the system at existing recycling plants.  相似文献   
57.
INTRODUCTION Rice (Oryza sativa L.) is one of the most im-portant crops in Pakistan. It is the third largest crop interms of area and production after wheat and cotton.Although rice in Pakistan is consuming large acreage,Pakistan is still far behind other rice producingcountries. The average yield is very low (2 t/ha) ascompared to Egypt (8.4 t/ha) and USA (6.6 t/ha).There are many reasons for this low yield. The mostimportant are high temperature (40?50 °C), low hu-midity at …  相似文献   
58.
A growing body of research argues that teachers’ beliefs and practices should be studied within the sociocultural contexts of their work because the relationship between their beliefs and practices is both complex and context-dependent. There is a need for further research in this area in understudied contexts such as developing countries, in order to promote effective education in schools and the professional development of teachers. This paper argues that if this ‘black box’ of sociocultural contexts in which science teachers are embedded is better understood, it may be possible to identify specific aspects of these contexts related to educational organizations that act as either supports or barriers to pedagogical reform or to implementing innovations in science education. Consequently, the main purpose of this study is to explore the sociocultural contexts of ten Egyptian science teachers and to what extent these sociocultural contexts help in understanding teachers’ pedagogical beliefs and practices. This paper, by utilizing a multi-grounded theory approach and qualitative methods, reveals a variety of sociocultural contexts that are related to teachers’ pedagogical beliefs and practices.  相似文献   
59.
Job performance can be defined as the extent to which one exhibits behaviors that further the goals of the organization, and leaders try to manage the factors influencing the performance in an organization to guide it toward organizational goals. A main factor that influences the performance is emotions and behavior of other people. The influence of people on each other can be divided into physical and metaphysical contagions in the scientific literature. In this article, we introduce a new kind of metaphysical contagion that has a close relationship with individual and organizational performance. We name it performance contagion and introduce two kinds of factors (content and process) and subfactors. We conceptualize a new concept in performance management defined as human resource layout. Tools are suggested for applying the steps of this model to improve both individual and organizational performance.  相似文献   
60.
This study seeks to describe the teachers’ professional development activities in Bangladesh and explores the hypotheses about the relationship between teachers’ traditional professional development activities and school improvement. Data from a representative sample of City secondary schools from Bangladesh (n = 127) were gathered through questionnaires from 127 principals and 694 teachers. Hierarchical multiple regression analysis was used in this research. This study found significant impacts of some of teachers’ professional development activities on school improvement. Also found that the maximum school improvement can be achieved if schools put more emphasis on teachers’ collaboration, in-service training and classroom observation and less emphasis on individual action enquiry. The findings of this study provide important information for the policy makers, educational managers and especially for the headmasters and teachers concerned with the improvement of teachers’ quality in secondary schools of Bangladesh. This study adopts a concurrent approach of data collection and analysis.  相似文献   
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