Students' reasoning about chemical bonding: The lacuna of repulsion     

Asnat R. Zohar  Sharona T. Levy 《科学教学研究杂志》2019,56(7):881-904

This article concerns a lacuna in chemistry students' reasoning about chemical bonding. Although chemistry students are familiar with the charges that make up the atom––both positive and negative––they refer only to the attraction between unlike charges. Specifically, they ignore the repulsion between the positive nuclei. We named this disregard of repulsion the lacuna of repulsion. Repulsion is a crucial component in the force-based explanation of chemical bonding, presenting the bond as a dynamic equilibrium between attraction and repulsion electrical forces. We noticed this lacuna incidentally while interviewing chemistry students for a bigger project aimed at supporting students in understanding the force-based explanation of chemical bonding. This article describes our systematic qualitative study of the lacuna of repulsion and its impact on mental models of 23 high school chemistry students. Our findings show that students use six mental models, most of them built upon each other. Beginning from a simple mental model that describes the chemical bond as electrons, continuing with the including attraction forces, and completing with repulsion and a dynamic view of the bond. Only when one considers both attraction and repulsion forces and understands the dynamic balance between them is it possible to build the force-based dynamic mental model of chemical bonding.  相似文献   

The osmium lamps     

Louis E. Levy  Samuel Sartain 《Journal of The Franklin Institute》1905,159(6):461-463

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Report of the committee on publications     

Louis E. Levy 《Journal of The Franklin Institute》1910,169(2):154-155

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The Colombian national apprenticeship service (SENA)     

Armando N. L. Negri 《Prospects》1976,6(2):240-244

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Does STES‐Oriented Science Education Promote 10th‐Grade Students’ Decision‐Making Capability?     

Tami Levy Nahum  David Ben‐Chaim  Ibtesam Azaiza  Orit Herskovitz 《International Journal of Science Education》2013,35(10):1315-1336

Today’s society is continuously coping with sustainability‐related complex issues in the Science‐Technology‐Environment‐Society (STES) interfaces. In those contexts, the need and relevance of the development of students’ higher‐order cognitive skills (HOCS) such as question‐asking, critical‐thinking, problem‐solving and decision‐making capabilities within science teaching have been argued by several science educators for decades. Three main objectives guided this study: (1) to establish “base lines” for HOCS capabilities of 10th grade students (n = 264) in the Israeli educational system; (2) to delineate within this population, two different groups with respect to their decision‐making capability, science‐oriented (n = 142) and non‐science (n = 122) students, Groups A and B, respectively; and (3) to assess the pre‐post development/change of students’ decision‐making capabilities via STES‐oriented HOCS‐promoting curricular modules entitled Science, Technology and Environment in Modern Society (STEMS). A specially developed and validated decision‐making questionnaire was used for obtaining a research‐based response to the guiding research questions. Our findings suggest that a long‐term persistent application of purposed decision‐making, promoting teaching strategies, is needed in order to succeed in affecting, positively, high‐school students’ decision‐making ability. The need for science teachers’ involvement in the development of their students’ HOCS capabilities is thus apparent.  相似文献   

Developmental assessment of the school-aged child with developmental disabilities     

Benjamin Levy 《Educational Psychology in Practice》2013,29(1):102-103

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Internationalised Reform: Overlapping Agendas in East Asian and Latin American Higher Education     

Levy  Daniel C. 《Minerva》1998,36(4):367-379

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Gender and ethnic differences in perceptions of equal opportunity climate and job outcomes of US Army Reserve component personnel     

Armando X. Estrada  Colin R. Harbke 《Int J Intercult Relat》2008,32(5):466-478

We examined equal opportunity climate (EOC) perceptions of reserve component personnel in the US Army (n = 949). We expected that gender and ethnic group membership would influence perceptions of the equal opportunity climate; and that gender and ethnic group membership would moderate the relationship between equal opportunity climate perceptions and ratings of job satisfaction, organizational commitment and workgroup effectiveness. Consistent with our hypothesis, we found the women and minorities perceptions regarding the equal opportunity climate were less favorable than White men. We also found that both gender and ethnicity moderated the relationship between equal opportunity climate perceptions and job outcomes of these groups. Our findings suggest that different groups are sensitive to particular aspects of EOC (e.g., harassment or discrimination) and that these sensitivities affect job-related outcomes.  相似文献   

Validation evidence for the Netherlands physical activity questionnaire for young children: the Iowa bone development study     

Janz KF  Broffitt B  Levy SM 《Research quarterly for exercise and sport》2005,76(3):363-369

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Emergent relations in pigeons following training with temporal samples     

Edson M. Huziwara  Saulo M. Velasco  Gerson Y. Tomanari  Deisy G. de Souza  Armando D. Machado 《Learning & behavior》2013,41(2):192-204

In two experiments, we investigated emergent conditional relations in pigeons using a symbolic matching-to-sample task with temporal stimuli as the samples and hues as the comparisons. Both experiments comprised three phases. In Phase I, pigeons learned to choose a red keylight (R) but not a green keylight (G) after a 1-s signal. They also learned to choose G but not R after a 4-s signal. In Phase II, correct responding consisted of choosing a blue keylight (B) after a 4-s signal and a yellow keylight (Y) after a 16-s signal. Comparisons G and B were both related to the same 4-s sample, whereas comparisons R and Y had no common sample. In Phase III, R and G were presented as samples, and B and Y were presented as the comparisons. The choice of B was correct following G, and the choice of Y was correct following R. If a relation between comparisons that shared a common sample were to emerge, then responding to B given G would be more likely than responding to Y given R. The results were generally consistent with this prediction, suggesting, for the first time in pigeons, the emergence of novel relations that involve temporal stimuli as nodal samples.  相似文献