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1.
Akinboro A Mohamed KB Asmawi MZ Sulaiman SF Sofiman OA 《Journal of Zhejiang University. Science. B》2011,12(11):915-922
In this study, freeze-dried water extract from the leaves of Myristica fragrans (Houtt.) was tested for mutagenic and antimutagenic potentials using the Allium cepa assay. Freeze-dried water extract alone and its combination with cyclophosphamide (CP) (50 mg/kg) were separately dissolved
in tap water at 500, 1000, 2000, and 4000 mg/kg. Onions (A. cepa) were suspended in the solutions and controls for 48 h in the dark. Root tips were prepared for microscopic evaluation. 2,2-Diphenyl-1-picrylhydrazyl
(DPPH) free radicals’ scavenging power of the extract was tested using butylated hydroxyanisole (BHA) and butylated hydroxytoluene
(BHT) as standards. Water extract of Myristica fragrans scavenged free radicals better than BHA, but worse than BHT. The extract alone, as well as in combination with CP suppressed
cell division, and induced chromosomal aberrations that were insignificantly different from the negative control (P≤0.05). However, cytotoxic and mutagenic actions of CP were considerably suppressed. The observed effects on cell division
and chromosomes of A. cepa may be principally connected to the antioxidant properties of the extract. The obtained results suggest mitodepressive and
antimutagenic potentials of water extract of the leaves of M. fragrans as desirable properties of a promising anticancer agent. 相似文献
2.
Melissa Ng Lee Yen Abdullah See Ching Mey Tan Kok Eng Rosly Othman Ahmad Fairuz Omar 《Journal of Research in Special Educational Needs》2013,13(4):259-271
Transition services are required by law for students with disabilities in many developed countries. In Malaysia, however, there is still no specific legislation mandating that school‐to‐work transition planning and services be provided to students with disabilities. This study investigated the state of the transition services provided by educational organisations to students with disabilities in Malaysia. A mixed method research design, which utilises both quantitative and qualitative research techniques, was employed to obtain information from 23 government organisations and NGOs involved in the education and training of students with disabilities. This study found that the organisations surveyed were aware of the lack of transition support and call attention to the importance of instituting a national policy on school‐to‐work transition services and supported employment systems for students with disabilities. The legislative and educational implications for Malaysia are discussed. 相似文献
3.
Izatus Shima Taib Siti Balkis Budin Seri Maseran Siti Nor Ain Jamaludin Mohamed Santhana Raj Louis Srijit Das Sulaiman Sallehudin Nor Fadilah Rajab Othman Hidayatulfathi 《Journal of Zhejiang University. Science. B》2009,10(11):813-819
Litsea elliptica Blume leaves have been traditionally used as medicinal herbs because of its antimutagenicity, che-mopreventative and insecticidal properties. In this study, the toxic effects of L. elliptica essential oil against Sprague-Dawley rat's red blood cells (RBCs) were evaluated. L. elliptica essential oil was given by oral gavage 5 times per week for 3 treated groups in the doses of 125, 250, and 500 mg/(kg body weight), respectively, and the control group received distilled water. Full blood count, RBC osmotic fragility, RBC morphological changes, and RBC membrane lipid were analyzed 28 d after the treatment. Although L. elliptica essential oil administration had significantly different effects on hemoglobin (Hb), mean cell hemoglobin concentration (MCHC), mean cell volume (MCV), and mean cell hemoglobin (MCH) in the experimental groups as compared to the control group (P<0.05), the values were still within the normal range. L. elliptica induced morphological changes of RBC into the form of echinoeyte. The percentage of echinocyte increased significantly among the treated groups in a dose-response manner (P<0.001). The concentrations of RBC membrane phospholipids and cholesterol of all treated groups were significantly lower than those of control group (P<0.001). However, the RBC membrane osmotic fragility and total proteins of RBC membrane findings did not differ significantly between control and treated groups (P>0.05). It is concluded that structural changes in the RBC membrane due to L. elliptica essential oil administration did not cause severe membrane damage. 相似文献
4.
Muhammad Khalifa 《International journal of qualitative studies in education》2013,26(2):259-282
This study examines Black student and parental perceptions of exclusionary practices of Black school principals. I ask why students and parents viewed two Black principals as contributing to abusive and exclusionary school environments that marginalized Black students. After a two-year ethnographic study, it was revealed that exclusionary behaviors toward Black students—which was viewed as “abuse” by students and parents—was a reproduction of the district's racism, and thus adds new considerations for discussions around the value of racially-like (i.e., all Black) educators and students. Parents perceived these two Black principals as dealing more harshly and rigidly with the Black students and their families; moreover, analysis of the interview data revealed that the principals rejected the cultural and social capital, and proclivities of Black students, and blamed Black students for their lower achievement and unique behaviors. I draw significant attention to the larger contexts of White supremacy and racism as I examine how Black principals negotiate their own roles, how they understand their own treatment of urban Black students, and how they are (knowing or unknowingly) reproducing oppressive practices of White supremacy on Black students in school. 相似文献
5.
Khalifa S. Al-Jabri 《Journal of The Franklin Institute》2011,348(7):1695-1716
This paper presents an overview of the modelling and simulation methods, which have recently been developed in the literature to simulate the behaviour of the beam-to-column joints at elevated temperature. These include curve-fit models, component-based models, finite element models, and artificial neural network models. The study concluded that the various numerical modelling methods can be used reliably to predict the behaviour of joints at elevated temperature to an acceptable degree of accuracy. 相似文献
6.
Hesham Khalifa Sherif A El-Safty Abdullah Reda Mohamed A Shenashen Alaa I Eid 《国家科学评论(英文版)》2020,7(5):863
We report on low-cost fabrication and high-energy density of full-cell lithium-ion battery (LIB) models. Super-hierarchical electrode architectures of Li2SiO3/TiO2@nano-carbon anode (LSO.TO@nano-C) and high-voltage olivine LiMnPO4@nano-carbon cathode (LMPO@nano-C) are designed for half- and full-system LIB-CR2032 coin cell models. On the basis of primary architecture-power-driven LIB geometrics, the structure keys including three-dimensional (3D) modeling superhierarchy, multiscale micro/nano architectures and anisotropic surface heterogeneity affect the buildup design of anode/cathode LIB electrodes. Such hierarchical electrode surface topologies enable continuous in-/out-flow rates and fast transport pathways of Li+-ions during charge/discharge cycles. The stacked layer configurations of pouch LIB-types lead to excellent charge/discharge rate, and energy density of 237.6 Wh kg−1. As the most promising LIB-configurations, the high specific energy density of hierarchical pouch battery systems may improve energy storage for long-driving range of electric vehicles. Indeed, the anisotropic alignments of hierarchical electrode architectures in the large-scale LIBs provide proof of excellent capacity storage and outstanding durability and cyclability. The full-system LIB-CR2032 coin cell models maintain high specific capacity of ∼89.8% within a long-term life period of 2000 cycles, and average Coulombic efficiency of 99.8% at 1C rate for future configuration of LIB manufacturing and commercialization challenges. 相似文献
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8.
Lam Wai Leong Othman Ibrahim Mohammad Dalvi-Esfahani Hamed Shahbazi Mehrbakhsh Nilashi 《Education and Information Technologies》2018,23(6):2477-2498
With numerous benefits of utilising mobile social network sites (SNSs) for learning purposes, limited studies have been conducted to determine the factors that influence the adoption of mobile SNSs in facilitating learning. Accordingly, the main purpose of this study is to explore the determinants of students’ behavioural intention to use mobile SNSs for their pedagogical purposes by utilising an extended version of Technology Acceptance Model. Furthermore, the moderating effect of users’ experience on their behavioural intention was investigated. Using a structured questionnaire, data were collected from 600 students from top-five public universities of Malaysia. The results revealed perceived task-technology fit as the great predictor of users’ intention and perceived usefulness. Although the moderating impact of students’ experience on the model found to be positive, it was not supported in this study. The contributions of this study both to the literature and practice are discussed. 相似文献
9.
Dr Othman N Alsawaie 《British journal of educational technology : journal of the Council for Educational Technology》2012,43(4):E128-E128
The book describes a five‐year teacher education programme at US's University of New Hampshire (unh ). It includes several research articles about what supports the programme, especially the internship (teaching practice) component, which is a full year long. The book is useful for educators especially those involved in teacher training and preparation. If the content of this book is likely to be relevant to you, I recommend that you arrange to borrow a copy for a while. Othman N Alsawaie 相似文献
10.
Hani T. S. Benamer Amin Bredan Omran Bakoush 《Health information and libraries journal》2009,26(3):240-245
Background: It is well established that Libya is lagging behind its peers in biomedical research. The aim of this study is to analyse all the original biomedical publications affiliated with Libya from 1973 to 2007. Methods: PubMed and the Science Citation Index Expanded were searched for ‘original research’ biomedical studies affiliated with Libya. The generated data were hand searched and 329 ‘original research’ studies were included in the analysis. Results: The first study was published in 1973. Publication rate peaked to an average of 15.2 studies per year during 1986–1996 and dropped to an average of 8.8 studies per year during 1997–2007. Of 166 first authors; 41% were Libyans and 59% were expatriates. The latter contributed 104 studies between 1986 and 1996 and 36 studies between 1997 and 2007, while the Libyans contributed 63 and 61 studies in the two respective periods. Authors affiliated with Benghazi produced 67% of the published studies, while authors from Tripoli produced 30% and other medical schools, hospitals and research centres from other Libyan cities produced only 3%. Conclusion: This study showed a decline in biomedical research publication in Libya. We propose that the lack of a research culture among the Libyan medical professionals is one of the factors contributing to this decline, which coincided with the departure of expatriate doctors from Libya. Raising awareness of the importance of research and improving research skills among Libyan medical professionals may help to reverse the current trend. 相似文献