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121.
Why do children learn in different ways: some are good students who show interest and zeal, while others are lazy and have to be taught against their will? Why do schools have over- and underachievers? Of course, there are a multitude of reasons. But almost 50 years ago it was shown using large data sets that families with high socioeconomic status are more likely to have children who are good students. Of course, there are many examples of successful students from poor families. However, they tend to be the exception to the rule. The certainty of success in school increases with rising socioeconomic status.  相似文献   
122.
Theory Competition and the Process of Change   总被引:1,自引:0,他引:1  
The reasons why many educational change initiatives have little impact are often framed in terms of either a poorly designed process on the part of the change initiator, or in terms of problems with the attitudes, skills and/or knowledge of those responsible for implementation. In this paper, we seek to integrate these two perspectives more closely by focusing on their interface and the competing theories frequently held by the change initiators and implementers. This concept of theory competition is illustrated with a case of a national literacy initiative in New Zealand in which the change initiators wished to raise the achievement of low performing students through the development of “learning-centred” leadership in schools and evidence-based practice. The desired outcomes were not achieved because theories about what it means to be a successful leader in such a situation, the data needed to undertake the type of evidence-based analysis envisioned and school personnel beliefs about the target students were understood differently by those responsible for initiating the change and those responsible for implementing it.  相似文献   
123.
A common trend in higher education is the “flipped” classroom, which facilitates active learning during class. The flipped approach to teaching was instituted in a haematology ‘major’ class and the students’ attitudes and preferences for the teaching materials were surveyed. The curriculum design was explicit and involved four major components (1) the preparation of the students; (2) the weekly pre-class work; (3) the in-class active learning strategies and (4) closing the learning loop using formative quizzes. Each of these components is discussed in detail and was informed by sound pedagogical strategies. Several different sources of information and several freely available software tools to engage the students are discussed. Two iterations are reported here, with improved pass rate for the final examination from 47 to 48 % in the traditional class to 56–65 % in the flipped classroom approach. The majority of students (93 and 89 %) came to the class prepared, after viewing the screencasts and engaged fully with the activities within the face-to-face time. The students perceived that solving case studies (93 %) was the most beneficial activity for their learning and this was closely followed by the production of essay plans (71 %). The majority of students recommended that this approach be repeated the following year (69 and 75 %).  相似文献   
124.
This research investigated the sources of explanations and understanding of natural phenomena in terms of the students’ cultural and school science experiences. The first phase involved interviews with eight village elders that probed their explanations and understanding of natural phenomena. The second phase involved the design, development and administration of two questionnaires on natural phenomena to 179 students in a rural boarding high school in Papua New Guinea (PNG). Most village elders gave explanations of many of the phenomena in terms of spirits, spells, magic, religion, and personal experiences. Most school-aged students choose scientific explanations of natural phenomena in terms of what they had learned in school or from personal experiences. However, many choose explanations of the same phenomena about spirits, spells and magic that came from the village, family or home. The study revealed that students’ ideas about natural phenomena are strongly governed and controlled by their school science knowledge in the school setting. It is likely that their own traditional knowledge cannot be identified in a school setting but that questionnaires in the students’ local language be given to students in their villages (as opposed to school). In addition, so as not to diminish the value of this traditional knowledge, science education programs are needed that are able to consider and harmonise traditional knowledge with school science.  相似文献   
125.
Platelets play a vital role in the progression of atherosclerosis and thrombosis, a major cause of death worldwide. Platelets are activated by many triggers like elevated LDL in blood resulting in aggregation and formation of plaque. The purpose of this study was to investigate the effect of LDL and signal transduction inhibitor on the activation of platelets in Ischaemic risk subjects. Platelets from IHD and hyperlipidemic subjects were hypersensitive to ADP, as higher levels of platelet aggregation were observed in these groups. LDL from IHD hyperlipidemic subjects was more effective in activating platelets from any other group. Ox-LDL was more effective in activating platelets than native-LDL as monitored by level of platelet aggregation induced by PAF and thrombin. Calcium channel blocker, nifedipine and verapamil inhibited platelet aggregation at micromolar level. Protein kinase inhibitor, staurosporine was effective in inhibiting ADP induced aggregation at nanomolar level.  相似文献   
126.
Urinary citric acid and calcium levels have been estimated in the urine of 20 normal healthy persons as well as 12 urinary stone patients. Inhibition efficiency of these urine samples towards the mineralisation of urinary stone forming minerals, viz., calcium phosphate, oxalate or carbonate, has been studied in an experimental model. Statistical correlation of the above data has been made by computing the coefficient of determination and unexplained variance. Clinico-biochemical indexing of calcium urolithiasis risk factor has been attempted in the light of the data.  相似文献   
127.
128.
Selecting the correct method for routine analysis by ‘method evaluation’ is an important component of quality assurance. It is a step-wise procedure that evaluates various analytical parameters like accuracy, precision etc of the given method. Finally reference intervals are established for selected population. We evaluated an enzymatic method for serum creatinine. The results show that it is an acceptable method based on the above mentioned criteria.  相似文献   
129.
In this paper a method for the realization of RC transfer immittance functions with an unsymmetrical lattice is presented. The method yields minimal capacitor realizations for Z12(s) with no pole at s = 0 and ?y12(s) having no pole at s = ∞. The number of resistors needed are only two more than the minimum needed.  相似文献   
130.
Acute coronary syndrome (ACS) is a term for a range of clinical signs and symptoms suggestive of myocardial ischemia. It results in functional and structural changes and ultimately releasing protein from injured cardiomyocytes. These cardiac markers play a major role in diagnosis and prognosis of ACS. This study aims to assess the efficacy of heart type fatty acid binding protein (h-FABP) as a marker for ACS along with the routinely used hs-TropT. In our observational study, plasma h-FABP (cut-off 6.32 ng/ml) and routinely done hs-Trop T (cutoff 0.1 and 0.014 ng/ml) were estimated by immunometric laboratory assays in 88 patients with acute chest pain. Based on the clinical and laboratory test findings the patients were grouped into ACS (n = 41) and non-ACS (n = 47). The diagnostic sensitivity, specificity, NPV, PPV and ROC curve at 95 % CI were determined. Sensitivity of hs-TropT (0.1 ng/ml), hs-TropT (0.014 ng/ml) and h-FABP were 53, 86 and 78 % respectively and specificity for the same were 98, 73 and 70 % respectively. Sensitivity, specificity and NPV calculated for a cut-off combination of hs-TropT 0.014 ng/ml and h-FABP was 100, 51 and 100 % respectively. These results were substantiated by ROC analysis. Measurement of plasma h-FABP and hs-TropT together on admission appears to be more precise predictor of ACS rather than either hs-Trop T or h-FABP.  相似文献   
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