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51.
目的:探索稻壳灰和人工砂在轻质油棕壳混凝土中部分替换水泥和细骨料对混凝土力学性能的影响,期望得到力学性能较高的轻质混凝土。方法:1.将不同比例的稻壳灰(5%,10%,15%和20%)替换水泥和100%的人工砂或石粉替换沙子,研究它们对混凝土抗压强度的影响;2.研究不同替换比例的稻壳灰(0和15%)和人工砂(0,50%和100%)对混凝土力学性能的综合影响。结论:1.在15%的稻壳灰替换水泥和100%人工砂替换沙子的情况下,最大抗压强度为51.49 MPa;2.替换比例为15%稻壳灰和100%人工砂的组合表现出最好的力学性能,包括抗压强度、抗拉强度、抗弯强度和杨氏模量。  相似文献   
52.
Human polycystic ovary syndrome (PCOS)—a cluster of diseases displays various symptoms associated with endocrine and gynecological disorders in childbearing women. Oral contraceptive pills (OCP) being a drug of choice minimizes symptoms and complications associated with the disorder. But, the controversial data available in literature regarding use of OCPs compels us to setup a study design regarding effect of OCP treatment in PCOS subjects and the possible outcomes specifically regarding coagulation pathways. Two PCOS study groups have been selected according to Rotterdam Criteria: one with OCP treatment (n = 50) and other without any drug treatment i.e., drug naive (n = 50). Anthropometry, Biochemistry, Hormones, Insulin and various clotting factors like Factor XI, Factor V, tPA, TAT-III and D-dimer were analyzed in both groups. The results showed worsening of IR, Metabolic parameters and coagulopathy in OCP group comparative to drug naive group indicating adverse effects of the OCP treatment which puts these women at risk for number of future clinical implications especially Cardiovascular and metabolic complications.  相似文献   
53.
Endothelial cell death due to increased reactive oxygen species(ROS) may contribute to the initial endothelial injury,which promotes atherosclerotic lesion formation.Piper sarmentosum(PS),a natural product,has been shown to have an antioxidant property,which is hypothesized to inhibit production of ROS and prevent cell injury.Thus,the present study was designed to determine the effects of PS on the hydrogen peroxide(H2O2)-induced oxidative cell damage in cultured human umbilical vein endothelial cells(HUVECs).In this experiment,HUVECs were obtained by collagenase perfusion of the large vein in the umbilical cord and cultured in medium M200 supplemented with low serum growth supplementation(LSGS).HUVECs were treated with various concentrations of H2O2(0-1000 μmol/L) and it was observed that 180 μmol/L H2O2 reduced cell viability by 50% as denoted by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay.Using the above concentration as the positive control,the H2O2-induced HUVECs were concomitantly treated with various concentrations(100,150,250 and 300 μg/ml) of three different extracts(aqueous,methanol and hexane) of PS.Malondialdehyde(MDA),superoxide dismutase(SOD),catalase(CAT) and glutathione peroxidase(GPX) levels showed a significant increase(P0.05) in HUVECs compared to the negative control.However,PS extracts showed a protective effect on HUVECs from H2O2-induced cell apoptosis with a significant reduction in MDA,SOD,CAT and GPX levels(P0.05).Furthermore,PS had exhibited ferric reducing antioxidant power with its high phenolic content.Hence,it was concluded that PS plays a beneficial role in reducing oxidative stress in H2O2-induced HUVECs.  相似文献   
54.
Communication technology is changing things. Language is no exception. Some language researchers argue that language is deteriorating due to increased use in electronic communication. The present paper investigated 100 randomly selected electronic mails (e-mails) and 50 short messaging system (SMS) messages of a representative sample of international students in University Putra Malaysia (UPM) to find out the impact of these two specific modes of electronic communication on written language use. The e-mails from UPM International Students Association (UPM-ISA) yahoo group were content analyzed. A non-probability convenience sampling was used to select the 50 short message services sent to the researcher about different subject matters by Malaysian and international students at UPM. Then, they were also content analyzed. The results indicated that the language used in students' e-mails and SMS messaging was full of spoken-like spelling, unconventional use of punctuation and abbreviations, and ungrammatical sentences. However, the more in-depth content analysis of the data revealed that the written language is being creatively adapted, developed, and enhanced to suit the conditions of the electronic communication age. Syntactical and lexical reductions are just strategies used to reduce effort, time and space.  相似文献   
55.
This article addresses the importance of obtaining a sample of an adequate size for the purpose of testing hypotheses. The logic underlying the requirement for a minimum sample size for hypothesis testing is discussed, as well as the criteria for determining it. Implications for researchers working with convenient samples of a fixed size are also considered, and suggestions are given about the steps that should be taken when they are not able to obtain a large enough sample. Finally, the implications of not having an adequate sample size for hypothesis testing are discussed to highlight the importance of determining sample size prior to conducting one’s study.  相似文献   
56.
This study determines the preferable leadership practised by colleges’ directors, institutional factors and challenges encountered in knowledge sharing in Malaysian technical higher learning institutions (HLIs). Using a pragmatic mixed-method strand, we obtained 212 teachers and instructors’ viewpoints on knowledge sharing factors and barriers. The study also interviewed four teachers in exploring college directors’ leadership practices and issues faced while sharing their knowledge and experiences with their colleagues. The findings revealed that technical college teachers favoured enabling others to act as a preferable leadership practice that empirically supports their knowledge sharing practices. Thus, reward system and culture were antecedents and significant predictors for teachers’ knowledge sharing practices in technical HLIs compared with their colleges directors’ transformational leadership practices. Teachers also highlighted that their directors provide affirmative responses concerning the knowledge sharing activities; thus, practising their roles as a knowledge sharing catalysts. However, lack of support from the management, micro-politics and teachers’ own negative perceptions were identified as challenges and constraints teachers encountered while sharing their knowledge with their peers. The findings put forward some suggestions for improvement on technical college’s knowledge sharing practices.  相似文献   
57.
This study describes the development of a basic computer-based play pedagogy intervention using a dyscalculia-remedy-oriented approach such as repetition and number orientation manipulation, and the investigation of its effect on children displaying dyscalculia characteristics. This computer play was evaluated in a group of 50 seven-year-old Malaysian children, who were low achievers in mathematics subject and were divided into control and intervention group. The intervention group engaged with the newly developed computer play for an hour per day for five consecutive days, while the control group attended normal classroom learning for the same time period. Overall post-test scores indicated that children from the intervention group performed significantly better than the control group after the five-day intervention period by 57.9%. Number disorientation and arithmetic operation confusion, which are common amongst the children displaying dyscalculia characteristics, were also significantly reduced after the intervention. This implies that the children benefitted from the computer play.  相似文献   
58.
59.
The study aimed to investigate whether heart-type fatty acid binding protein (H-FABP) measurement provides additional diagnostic value to that of conventional cardiac markers in acute myocardial infarction (AMI) within first 6 h after the onset of symptoms. The study included 120 subjects: 60 AMI cases and 60 age and sex matched controls. The cases and controls were further divided into 2 subgroups depending on the time since onset of chest pain as (1) subjects within 3 h and (2) between 3 and 6 h of onset of chest pain. In all the cases and controls, serum H-FABP concentration was measured by Immunoturbidimetric method, serum Troponin I and myoglobin concentrations by Chemiluminescence immunoassay and serum CK-MB concentration by Immuno-inhibition method. The sensitivity, specificity, positive and negative predictive values of H-FABP were significantly greater than CK-MB and myoglobin but were lesser than Troponin I in patients with suspected AMI in both within 3 h and 3–6 h groups. Receiver operating characteristic curves demonstrated greatest diagnostic ability for Troponin I (AUC = 0.99, p < 0.001) followed by H-FABP (AUC = 0.906, p < 0.001) within 3 h and 3–6 h after the onset of chest pain. In conclusion, the diagnostic value of H-FABP is greater than CK-MB and myoglobin but slightly lesser than troponin I for the early diagnosis of AMI within first 6 h of chest pain. H-FABP can be used as an additional diagnostic tool for the early diagnosis of AMI along with troponin I.  相似文献   
60.
The main aim of the study was to evaluate trainee teachers working commitment in their teaching practicum. There were seven component teaching practices and eleven demographic factors. The instrument of the study was extracted from various sources to suit the research design based on Units, Treatments, Observing, and Surveying (UTOS) model modification. The reliability index obtained for both research instruments were reasonably good ranging from 0.7030 to 0.9053. A total of 276 trainee teachers who were doing their practical teaching in one of the state in Malaysia (Kelantan). Stratified random sampling was used. They made their self-assessment by using the working commitment instrument. At the same time, their teaching processes were guided through conferences, observations and finally evaluations to get their comparative scores of teaching performance. The data were analyzed by using statistical multiple regression at significant ofp 〈 0.05. As a result, a linear equation of trainee teachers' commitment comprises contribution of work load, work satisfaction, study opportunities, teachers' prospect, marital status, teaching practices, planning and preparation teaching procedure, and religious studies. Furthermore the findings of this study led to some suggestions for future teachers development and become more efficient and adaptive.  相似文献   
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