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41.
To study the influence of negative or positive experience of the ingestion of ethanol in femaleDrosophila with thefast form of the Adh gene on the acceptance of a medium containing this substance as site for egg laying, flies raised on a medium without alcohol were kept (1) on a regular medium, (2) on a medium supplemented with ethanol, (3) on a medium supplemented with 4-methylpyrazole (4-MP, an inhibitor of the enzyme ADH), and (4) on a medium containing both ethanol and this inhibitor. Whereas theDrosophila exhibited no spontaneous egg-laying preference for ethanol, a preference was induced by the ingestion of this substance, which also led to an increase in the number of eggs laid. By contrast, ingestion of ethanol, associated with the inhibitor, reduced the number of eggs laid and led to an avoidance of ethanol-containing media. Flies treated with ethanol and 4-MP exhibited signs of sickness (reduction in locomotor activity and loss of balance). The egg-laying preference for the ethanol results from learning linked to the metabolic utilization of this alcohol. The adaptative significance of this learning is discussed. 相似文献
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Recent research related to the design of science instruction is often based on conceptual change theory and requires assessments of what knowledge students bring to instruction. The premise of this study was that it is also important to understand when and how students apply their knowledge. Fourteen elementary and middle school teachers in an in-service physics course were asked to solve qualitatively a variety of series and parallel circuit problems and explicate their reasoning. These teachers were found to share a common core of strongly held propositions that formed a coherent, but incorrect and contradictory model of sequential current flow. Yet their predictions about the circuits were highly variable. The variability in predictions resulted from differences and contradictions in additional “protective belts” of propositions, and differences in the ways in which the teachers changed and selectively applied those propositions to different problems. Understanding the variations in not only what teachers knew, but also the differences in when and how they applied their knowledge complicated the task of designing instruction. However, it also made possible the design of more precise instruction in which the teachers were required to recognize, confront, and reconcile specific inconsistencies in their beliefs. 相似文献
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Florrie Fei‐Yin Ng Irene Nga‐Lam Sze Catherine S. Tamis‐LeMonda Diane N. Ruble 《Child development》2017,88(3):979-995
Academic socialization by low‐income immigrant mothers from Mainland China was investigated in two studies. Immigrant Chinese mothers of first graders (n = 52; Mage = 38.69) in the United States (Study 1) and kindergartners (n = 86; Mage = 36.81) in Hong Kong (Study 2) tell stories that emphasized achieving the best grade through effort more than did African American (n = 39; Mage = 31.44) and native Hong Kong (n = 76; Mage = 36.64) mothers, respectively. The emphasis on achievement was associated with mothers' heightened discussion on discrimination (Study 1) and beliefs that education promotes upward mobility (Study 2), as well as children's expectations that a story protagonist would receive maternal criticism for being nonpersistent in learning (Study 2). 相似文献
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Barbieri Christina Areizaga Booth Julie L. Begolli Kreshnik N. McCann Nicholas 《Instructional Science》2021,49(4):419-439
Instructional Science - The present study examines the effectiveness of incorporating worked examples with prompts for self-explanation into a middle school math textbook. Algebra 1 students... 相似文献
49.
The perceptions, knowledge, and opinions of 104 teachers of students with learning disabilities regarding medication used with their students were investigated. The students' doctors were perceived as the professionals primarily responsible for making the decision to have the student either placed on or taken off medication. The teachers indicated that global impressions and direct behavioral observations were used to assess the effects of medication but that they would prefer to use behavioral observations and rating scales. Hyperactivity and delusions/hallucinations were perceived as the problems most likely to lead to medication. Less than 15% of the teachers indicated that their professional preservice training had provided them with sufficient information on the use of medication for children with behavior problems, and less than 20% had a similar opinion regarding their inservice training on the same topic. 相似文献
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Alistair D. N. Edwards 《Educational Media International》2013,50(2):100-103
Abstract In 1988 the Open University is implementing a major new policy on the use of computers in its courses; students taking certain courses will be obliged to have access to a microcomputer. This new policy has many far‐reaching consequences, not least for students who are disabled. In the past most computing in Open University courses has been done by students using terminals in local study centres, linked to the University's mainframe computers. Also, a number of students who are disabled have used computers in their studies, principally for word‐processing written work. By interviewing disabled students who have taken such courses, and surveying other disabled students, it has been possible to anticipate to some extent the likely impact of the home‐computing (HC) policy. Results suggest that for many disabled‐ students the HC policy represents an improvement in their opportunities; now they will be able to study courses involving computers entirely at home. However, a number of problems have also been identified. Hopefully, as many of these have been recognised at an early stage, it will be possible to address them before they affect students directly. 相似文献