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41.
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   
42.
The present study aims to assess and compare the biochemical oxidative stress markers in male smokers and non-smokers with chronic periodontitis. One hundred thirty-four male chronic periodontitis patients and 64 apparently healthy male volunteers were recruited for the study. The periodontal status was evaluated by measuring gingival index, plaque index, papillary bleeding index and clinical attachment loss using UNC-15 probe. The biochemical markers estimated were total antioxidant capacity, RBC-superoxide dismutase, glutathione peroxidase, vitamin C, malondialdehyde and C-reactive protein. The obtained results indicate higher oxidative stress in chronic periodontitis. Smokers with chronic periodontitis show significantly higher periodontal clinical parameters and relatively higher systemic oxidative stress. Vitamin C estimation may be an important biochemical parameter in conjunction with clinical parameters for diagnosis of chronic periodontitis in smokers.  相似文献   
43.
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   
44.
Abdul Jamil Urfi 《Resonance》2013,18(5):468-474
Since evolution forms the core of modern biology, teaching about natural selection is extremely important as this equips the student to frame the ‘why’ questions properly and, at the same time, sharpens their understanding about a host of issues pertaining to behaviour, diversity and genetics.  相似文献   
45.
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   
46.
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   
47.
建立知识社会   总被引:1,自引:0,他引:1  
人类社会正经历着向知识社会的转变;知识正日益成为经济发展和社会进步的核心因素.身处全球迈向知识社会的进程之中,我们目睹和亲历着世界性的合作、竞争、流动和创新.技术变革无疑是这一进程的强大驱动力之一;而在技术不断取得极大进步,知识与信息以空前的数量产生和极快的速度传播的同时,也存在着知识鸿沟或数字鸿沟现象.  相似文献   
48.
Since its inception 30 years ago, the then Department of Engineering Science, Institut Teknologi MARA (ITM) was given the responsibility of preparing all the students in the first year engineering programmes by giving enough knowledge in basic science and mathematics. The nation's vision to become a fully‐industrialised economy by the year 2020 required all institutes of higher learning (IHLs) in Malaysia to increase their intake of students in the science and technology courses, especially in engineering. However, at the upper secondary education level, students have the freedom to choose between the science‐based or non‐science combination of subjects. This has led to a dearth of science‐based students enrolling in IHLs. Because ITM believes that it is possible to educate individuals from various backgrounds, the engineering courses are open to students with a variety of academic qualifications. Special bridging courses were designed and created for such students since late 1996. The success or failure of the new courses can be assessed after the students have gone through the proper first year engineering courses which consist of Mathematics, Physics and Chemistry. This paper reports on a pilot study on the pioneer groups of students with variable entry qualifications to assess the effectiveness of the courses. The study involved the analysis of the students’ examination results as a performance indicator, and it was found that the bridging programme for non‐science students needed to be redesigned. It is also proposed that to improve the quality of the programme, and hence students’ performance, a regular review be conducted, student support activities be continued and to expand the use of self‐study materials.  相似文献   
49.
INTRODUCTION Biosphere pollution by heavy metals and nu-cleotides was accelerated dramatically during the last few decades due to mining, smelting, manufacturing, treatment of agricultural soils with agro-chemicals and soil sludge, etc. Problems associated with the contamination of soil and water such as animal wel-fare, health, fatalities and disruptions of natural eco-systems are well documented (He et al., 2005). Heavy metals such as Pb, Cr, As, Cu, Cd, and Hg, being added to our so…  相似文献   
50.
Abstract

This paper is a conceptual analysis in methodology. The purpose it fulfils is that of analysing the critical and dialogic pedagogy of Paulo Freire, to arrive at implications of Freire’s philosophy and approach for the current educational context of the Kingdom of Bahrain. The Bahraini context is currently one of major economic, social, and educational reforms. Despite several reform initiatives, however, schools in Bahrain are still not advancing as they should be and deficiencies continue to exist in students’ development of higher-order thinking skills, such as critical thinking, problem-solving, and analysis. Among the implications made by this study are ones related to: teaching and learning practices within a classroom, cultivation of 21st Century skills, curriculum development and planning, and the role played by the teacher. The paper ends with a number of significant recommendations for teachers and policy-makers, which can enhance education in Bahrain and help it progress faster. These recommendations can also prove to be useful to other parallel contexts regionally and internationally.  相似文献   
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