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An experimental design was adopted in the present study to cross-compare the effect of two formative assessments, namely peer assessment (PA) and teacher assessment (TA), with summative assessment (SA) on the improvement of language learners’ writing skill and self-efficacy. Writing excellence was operationalized by structural (grammar), lexical (word choice), and discoursal (cohesion and coherence) well-formedness. Furthermore, focused group interview was run to elicit the learners' attitudes and preferences toward type of assessment. Three cohorts of proficiency-matched language learners sat for a semester-long experimentation (20 sessions × 90 min = 30 h) and three testing sessions. The results revealed that PA group significantly improved in the writing skill, but TA and SA groups did not. Self-efficacy was not enhanced in any of the assessment groups under study. The interviews and follow-up member checkings indicated that the pupils did not have positive attitudes toward PA and preferred TA. Among the sources of this disfavor, they referred to misunderstanding, lack of knowledge or attention, tiredness, poor handwriting of the assesse, shyness, friendship bias, and even feeling not qualified enough to judge their peers’ tasks. Overall, then, the study reported a mismatch between the students’ actual performance and attitudinal beliefs under different assessment conditions, implying that (a) Iranian students are more inclined toward teacher-dominated pedagogies and (b) triangulation of assessment modes provides more reliable optimal results. 相似文献
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Paulo Blikstein Tamar Fuhrmann Shima Salehi 《Journal of Science Education and Technology》2016,25(4):513-526
In this paper, we investigate an approach to supporting students’ learning in science through a combination of physical experimentation and virtual modeling. We present a study that utilizes a scientific inquiry framework, which we call “bifocal modeling,” to link student-designed experiments and computer models in real time. In this study, a group of high school students designed computer models of bacterial growth with reference to a simultaneous physical experiment they were conducting, and were able to validate the correctness of their model against the results of their experiment. Our findings suggest that as the students compared their virtual models with physical experiments, they encountered “discrepant events” that contradicted their existing conceptions and elicited a state of cognitive disequilibrium. This experience of conflict encouraged students to further examine their ideas and to seek more accurate explanations of the observed natural phenomena, improving the design of their computer models. 相似文献
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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
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Siti Balkis Budin Seri Masran Siti Nor Ain Baharuddin Omar Izatus Shima Taib Othman Hidayatulfathi 《Journal of Zhejiang University. Science. B》2012,13(10):783-790
Litsea elliptica Blume has been traditionally used to treat headache, fever, and stomach ulcer, and has also been used as an insect repellent. The acute and subacute toxicities of L. elliptica essential oil were evaluated orally by gavage in female Sprague-Dawley rats. For the acute toxicity study, L. elliptica essential oil was administered in doses from 500 to 4 000 mg/kg (single dose), and in the subacute toxicity test, the following doses were used: 125, 250, and 500 mg/kg, for 28 consecutive days. In the acute toxicity study, L. elliptica essential oil caused dose-dependent adverse behaviours and mortality. The median lethal dose value was 3 488.86 mg/kg and the acute non-observed-adversed-effect level value was found to be 500 mg/kg. The subacute toxicity study of L. elliptica essential oil did not reveal alterations in body weight, and food and water consumptions. The haematological and biochemical analyses did not show significant differences between control and treated groups in most of the parameters examined, except for the hemoglobin, mean cell hemoglobin concentration, mean cell volume, mean cell hemoglobin, serum albumin, and serum sodium. However, these differences were still within the normal range. No abnormalities or histopathological changes were observed in the liver, pancreatic islet of Langerhans, and renal glomerulous and tubular cells of all treated groups. In conclusion, L. elliptica essential oil can be classified in the U group, which is defined as a group unlikely to present an acute hazard according to World Health Organization (WHO) classification. 相似文献
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Leila Sadeghmoghadam Sahar Ahmadi Babadi Ali Delshad Noghabi Shima Nazari 《Educational gerontology》2013,39(7):476-482
Background and purpose: The perception of aging is one of the independent predictors of functional disability and mortality in the aged ones, this study was conducted to compare the follow-up of a training program with the use of two in-person and telenursing methods on the perception of aging of the elderly, covered by the comprehensive health centers in Ahvaz city.Materials and Methods: This quasi-experimental study involved systematic random sampling conducted on 60 elderly persons (aged 60–75 years) who were referred to in Ahvaz. A training program was conducted for all elderly persons for 3 weeks (three sessions per week), which was accompanied with 2 months of six follow-ups for the telephonic follow-up group (Tele-nursing), and two follow-ups for in-person follow-up group. The data were collected with the use of demographic form, Abbreviated Mental Test (AMT), and The Brief Aging Perceptions Questionnaire (B-APQ). Elderly completed the questionnaire at the beginning of the study and 8 weeks later. The data were subsequently analyzed with SPSS software; and P values less than 0.05 were considered significant.Results: Based on the results, the mean score of perception of aging increased in the study groups after the intervention. This increase was statistically significant only in the intervention group.Discussion and Conclusion: The telephonic follow-up was more effective on Increasing the perception of aging compared with the in-person follow-up. Therefore, using this method is recommended for the elderly. 相似文献
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An exo-atmospheric interception scenario between an accelerating missile and its target is investigated. It is assumed that the maneuvering acceleration is obtained by instantaneous rotation of the missile's body to the required attitude. Two different guidance laws are derived for such an interceptor using the sliding mode control methodology. The difference is in the definition of the sliding surface enforcing different trajectories for the interceptor. It is shown that if this surface is chosen as the zero-effort-miss of the well-known proportional navigation guidance law, then the missile is commanded to point its acceleration vector along the line-of-sight and consequently fly along a curved trajectory. For the second guidance law, a unique sliding surface is chosen enforcing the missile to fly on a straight line towards collision, after the initial heading error is nulled. The performance of the guidance laws is analyzed and compared using a nonlinear two dimensional simulation. It is shown that on top of enforcing a different flight geometry for the interceptor, the use of the new guidance to collision sliding mode guidance law can enhance the capture zone of the interceptor. 相似文献
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Bumbacher Engin Salehi Shima Wieman Carl Blikstein Paulo 《Journal of Science Education and Technology》2018,27(3):215-235
Journal of Science Education and Technology - Manipulative environments play a fundamental role in inquiry-based science learning, yet how they impact learning is not fully understood. In a series... 相似文献
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