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141.
Graphs are one of the primary means of exploration and communication in the practice of science, but students in science laboratories are customarily taught only the low-level mechanics of constructing a single kind of graph when given a table of information. The use of a microcomputer can relieve the drudgery of plotting, allowing students to pursue higher-level issues in the design and interpretation of graphs through repeated “thought experiments.” We introduced computer-assisted graphical data analysis to inner-city high school students with weak math and science backgrounds, emphasizing the dynamic manipulation of various kinds of graphs to answer specific questions. Drawing on extensive recordings and classroom observations, we describe examples of the performance of these students on open-ended problem-solving tasks in which graphs can be used to arrive at meaningful answers to applied data analysis problems.  相似文献   
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Multidimensional sealing and related analytic procedures were used to estimate the accuracy of a set of goals used to pattern the design of a graduate curriculum. The analysis suggests that this goal set faithfully represents the essential elements within the area of professional practice to be taught. The procedures described have utility for a wide range of goal-focused analyses.  相似文献   
144.
The results of recent studies into the use of the concept mapping heuristic seem to demonstrate that meaningful learning results through its use in science classrooms. While this underscores the need to use more effective instructional strategies in science teaching, the issue of the intervening variable of anxiety in learning and science achievement, and the possible use of a metacognitive strategy in anxiety reduction have not been addressed. This study, therefore, sought to find out if the metacognitive strategy of concept mapping reduces anxiety and thereby enhances achievement in biology. A total of 51 (30 boys, 21 girls) senior secondary one (grade 10) students participated in this experiment. Two instruments—the Zuckerman Affect Adjective Checklist and the Biology Achievement Test—were used in pre- and posttest administrations to measure the treatment effect on anxiety and achievement, respectively. Findings support the stand that concept mapping is significantly more effective than the traditional/expository teaching strategy in enhancing learning in biology. In addition, it apparently reduces students' anxiety towards the learning of biology. A significant reduction of anxiety was noticed for male subjects.  相似文献   
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Sialic acid, the end moieties of the carbohydrate chains are biologically important and essential for functions of glycoconjugates and are reported to be altered in cancer patients. Two hundred and twenty five breast cancer (BC) patients, 100 patients with benign breast disease (BBD) and 100 healthy females (controls) were enrolled for the study. Eight hundred and twenty four follow-up samples of 225 breast carcinoma patients were also evaluated. The association of sialic acid forms, sialyltransferase and α-2–6 sialoproteins levels with presence and extent as well as prognosis of breast carcinoma was studied. Serum sialic acid forms and sialyltransferase revealed significantly elevated levels among untreated breast cancer patients as compared to the controls, patients with BBD as well as cancer patients in remission. Non-responders showed comparable levels of the markers with those found in breast cancer patients at the time of diagnosis. Higher levels of sialic acid forms at diagnosis were associated with poor prognosis. A positive correlation between serum levels of different forms of sialic acids and extent of malignant disease was observed. The changes in serum proteins with terminal α-2–6 sialic acid correlated well with alterations in the levels of sialic acid forms and sialyltransferase. Malignant tissues showed elevated levels of sialic acid and sialyltransferase as compared to surrounding normal tissues. The results suggested potential utility of these markers in evaluation of clinical outcome.  相似文献   
147.
The rate of citation duplication was examined in three databases: MEDLINE, BIOSIS, and LIFE SCIENCES COLLECTION. Duplicate citations were found to be more pertinent than unique citations. The duplicate citations came from a highly compact literature, while those from a single database were very widely scattered. The pertinent duplicated citations were more likely to be retrieved in searches that had more terms overall, had a higher percentage of thesaurus terms, and had terms which appeared in both title and abstract. These results suggest that the rate of duplication of citations in multidatabase searches may be used to rank output according to probable pertinence.  相似文献   
148.
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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We present a practical way of adapting and using four research-based assessments for different purposes in an electricity and magnetism course for K-8 science teachers. The course is designed to accomplish conceptual change toward accepted scientific conceptions as well as introducing teachers to materials and activities appropriate for their classrooms. Our data support that using the research-based tests to identify alternative conceptions and discuss test results with teachers is a promising way to use the knowledge of alternative conceptions in professional development. We also identify some mismatches between the research of conceptual change and its use in programs of professional development.
Ji ShenEmail:
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