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51.
Professor Peter Fensham Dr. Kathiravelu Navaratnam Dr. Warren Jones Professor Leo West 《Research in Science Education》1991,21(1):80-89
One set of measures of the quality of courses for the preparation of science teachers stems from the perceptions exit students
have of their knowledge with respect to that teaching. The Discipline Review of Teacher Education in Mathematics and Science
surveyed these students late in 1988 on three broad types of knowledge-science content knowledge, curriculum knowledge, and
pedagogical knowledge. Some of these findings of the Review are described. In addition, the base for developing items to measure
these three types of knowledge is discussed in this paper. The variety in the data that emerged is also presented and the
consistency of the findings with other measures of quality is described.
Specialisations: science and technology curriculum, environmental education, educational disadvantage.
Specialisations: research and evaluation in teacher education, technical and further education and total quality management.
Specialisations: research in educational systems. 相似文献
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53.
Three experiments showed a savings procedure to be an effective and sensitive alternative to sensory preconditioning procedures as a measure of associations among neutral stimuli. Experiment 1 showed that within-compound associations developed more rapidly in reinforced appetitive serial compound conditioning when nonreinforced preexposure to the serial compound was given than when separate element or no preexposure was given. Experiment 2 showed the savings effect to be highly stimulus specific. Experiment 3 examined the facilitation of serial compound conditioning after either simultaneous or serial nonreinforced preexposure to the elements of the compound. The results of that experiment were consistent with those of analogous sensory preconditioning experiments. When preexposure involved only the two elements of the subsequently reinforced compound, serial preexposure produced more savings than simultaneous preexposure. But when preexposure involved a three-stimulus procedure like that used by Rescorla (1980b), simultaneous preexposure resulted in more savings. Advantages of the savings procedure over sensory preconditioning as a measure of association among neutral stimuli are discussed. 相似文献
54.
Nam Cao Hoai Le Murat Gel Yonggang Zhu Jian Wang Helen Dacres Alisha Anderson Stephen C. Trowell 《Biomicrofluidics》2014,8(6)
Bioluminescence resonance energy transfer (BRET) is a form of Förster resonance energy transfer. BRET has been shown to support lower limits of detection than fluorescence resonance energy transfer (FRET) but, unlike FRET, has not been widely implemented on microfluidic devices for bioanalytical sensing. We recently reported a microscope-based microfluidic system for BRET-based biosensing, using a hybrid, high quantum-efficiency, form of BRET chemistry. This paper reports the first optical fiber-based system for BRET detection on a microfluidic chip, capable of quantifying photon emissions from the low quantum-efficiency BRET2 system. We investigated the effects of varying core diameter and numerical aperture of optical fibers, as well as varying microfluidic channel design and measurement conditions. We optimized the set-up in order to maximize photon counts and minimize the response time. The optimized conditions supported measurement of thrombin activity, with a limit of detection of 20 pM, which is lower than the microscope-based system and more than 20 times lower than concentrations reported to occur in plasma clots. 相似文献
55.
Rai S Kookana Basant Maheshwari Peter Dillon Seema H Dave Prahlad Soni Hakimuddin Bohra 《International Journal of Inclusive Education》2016,20(11):1155-1171
A survey was conducted in eight secondary schools located in two watersheds in Gujarat and Rajasthan (semi-arid region of India) to assess students’ perceptions about groundwater scarcity issues and the impact of the scarcity on their educational opportunities. Survey responses to a detailed questionnaire by a cohort of students in both watersheds; school attendance records of year 8 class students (13–14 years old) and responses gathered via a socio-economic survey involving 500 families in the study area were used in the study. In both watersheds, >90% students identified groundwater scarcity as a major issue. Required to work at home or farm, about 65% students in Gujarat and 60% in Rajasthan missed school for up to 2 days/month; and a smaller proportion (~ 30%) missed schools for 4 or more days/month. School absenteeism was found to be linked with gender; female students missed schools more frequently than their male counterpart. The school attendance records in Rajasthan showed that the frequency of female students missing schools for 5 or more days/month was on an average 2–10 times greater than that for males. The gender difference in absenteeism in all schools was statistically significant (P?<?.018**). The study highlighted that groundwater scarcity in the study area, and consequent demand on their time for household work including fetching drinking water are contributing factors towards limiting their educational and economic opportunities. Groundwater scarcity can be one of the key factors that can limit inclusiveness and empowerment of women and need to be considered in policy-making. 相似文献
56.
Peter S. Kaplan Jo-Anne Bachorowski & Patricia Zarlengo-Strouse 《Child development》1999,70(3):560-570
Child-directed (CD) speech segments produced by 20 mothers who varied in self-reported symptoms of depression, recorded during a structured play interaction with their 2- to 6-month-old infants, were used as conditioned stimuli with face reinforcers in a conditioned attention paradigm. After pairings of speech segments and faces, speech segments were assessed for their ability to increase time spent looking at a novel checker-board pattern (summation test) using 225 4-month-old infants of nondepressed mothers. Significant positive summation, an index of associative learning, was obtained in groups of infants tested with speech produced by mothers with comparatively fewer self-reported symptoms of depression (Beck Depression Inventory or BDI < or = 15). However, significant positive summation was not achieved using speech samples produced by mothers with comparatively more symptoms of depression (BDI > 15). These results indicate that the CD speech produced by mothers with symptoms of depression does not promote associative learning in infants. 相似文献
57.
The Competitive State Anxiety Inventory-2 (CSAI-2) is one of the most frequently used instruments when assessing competitive state anxiety in sport psychology research. However, doubts have been expressed about the factorial validity of both the English and the Greek versions of the scale. Hence, a revised version of the inventory (CSAI-2R) has recently been suggested to be more psychometrically sound (Cox et al., 2003). In the present study, the aim was to evaluate the psychometric properties of the Swedish version of the CSAI-2 using confirmatory factor analyses. A total of 969 athletes (571 men and 398 women) competing in 26 different sports completed the Swedish version of the CSAI-2. Three different factor structures were evaluated: the original three-factor model (with cognitive anxiety, somatic anxiety and self-confidence), a two-factor model in which self-confidence was excluded, and a three-factor model containing 17 items (CSAI-2R). The results revealed that only the 17-item model displayed an acceptable fit to the data. Although some doubts remain about the amount of variance that can be attributed to error variance in the subscales, the results suggest that it is better to use the CSAI-2R rather than the original CSAI-2. 相似文献
58.
Peter Mazikana 《International Information and Library Review》2013,45(3-4):307-317
This paper examines the need for re-evaluating archival principles and practices. Opportunities created to enhance and enrich archival work and difficulties of archiving digital information, because of its nature, are reviewed. “Records series” are used to illustrate the consequences in terms of selection and appraisal of records. The preservation of digital information also raises new challenges. The impact of digital information on the ethical, legal and societal issues (protection, confidentiality, privacy, etc.) is emphasized. 相似文献
59.
The paper presents a model that evaluates how upgraded technological capabilities of emerging country based multinationals (EMNCs) and an increase in the domestic market size of large emerging countries affect value chain location choices and the competitiveness of emerging country based firms versus advanced country based ones. The model shows that, even without possessing a competitive advantage in terms of technology and/or brands, EMNCs from large or rapidly technologically advancing countries can become dominant players in the global system. The model highlights the central role of firm level technological intensity and product differentiation in determining the location of value chain activities as well as defining organisational boundaries. Empirical analysis of the location choices of the world's top multinationals from large advanced and emerging countries in 2010 supports the model's predictions. 相似文献
60.