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101.
College instructors often teach scientific thinking by asking students to review and analyze a primary research article. The main purpose of this study was to explore how classroom response systems (CRS) could help impact the quality of written analysis papers submitted for this assignment by students taking 100‐level biology courses at a medium‐sized suburban, two‐year college in the northeastern United States. Students in all participating course sections received written instructions on five key elements of critical analysis (CA) to include in scientific study analysis papers. Classroom instruction on recognizing these key elements in primary research papers was provided either via CRS or via an instructor‐facilitated classroom discussion enhanced by the same PowerPoint presentation. A rubric, designed specifically for this assignment, was validated prior to its use in this study. Fifty students participated in the study, and those who received the CRS intervention achieved significantly higher CA scores for identifying implications of study findings, while the group that received only written instructions achieved significantly higher CA scores for discussing the credibility of the references used by the authors in planning the critiqued study. The implications of this study are discussed along with ideas for future research.  相似文献   
102.
To contribute to an understanding of the nature of teachers’ mathematical knowledge and its role in teaching, the case study reported in this article investigated a teacher’s conception of a metamathematical concept, definition, and her use of examples in doing and teaching mathematics. Using an enactivist perspective on mathematical knowledge, the authors give an account of the case of Lily, a prospective, then beginning, teacher who conceived of mathematical definition as an object with particular form and function and engaged in purposeful, specialized use of examples when doing and teaching mathematics. Lily’s case illustrates how a teacher’s interpretation of examples (as exemplifications or single instances) and conception of the form and function of definitions can influence her doing and teaching mathematics. An implication is that teacher preparation should foster teachers’ abilities to use examples purposefully to provide students with rich opportunities to engage in mathematical processes such as defining.  相似文献   
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104.
Atomic force microscopy (AFM) has been employed to observe in real-time and in an aqueous environment the process of ethidium bromide induced supercoiling in individual DNA plasmid molecules. Image data reveal both the onset and the progressive presence of plectonemic DNA supercoiling. In addition, significant molecular motion of the surface adsorbed DNA is observed. These data illustrate the potential of AFM in the time-resolved study of biomolecular processes, and hence, provide new insights into biomolecular structure and function.  相似文献   
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106.
This paper reviews affect control theory's major strengths, the contributions of recent work to its growth, and the most promising avenues for future work. Affect control theory's strengths include (1) the precision of its mathematical statement and empirical base (especially when compared with earlier interpretive sociologies), (2) its ability to link the internal processing that generates social action to the socio‐cultural system upon which that action is based, and (3) the generality that allows a parsimonious explanation of a wide range of processes and previous research findings. Recent advances provide (1) new, more accurate impression‐change formulas, (2) the expansion of the theory to encompass settings, emotions, and traits, (3) new dictionaries of evaluation, potency and acitivity meanings and (4) tests of the theory using likelihood judgments, verbal scenarios and actual behavior of naive experimental subjects. Further work must include links to cognitive structures that will further delineate definition of situation and behavior selection processes. In addition, integration of affect control theory with new sociological work on the development of shared social knowledge and on institutionalized production systems expand the theory in useful ways. Finally, new work must find innovative and convincing ways to test simulation outcomes using both verbal accounts and behavior.  相似文献   
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108.
The study "Mathematics Teaching in the 21st Century (MT21)" focuses beyond others on the measurement of teachers’ general pedagogical knowledge (GPK). GPK is regarded as a latent construct embedded in a larger theory of teachers’ professional competence. It is laid out how GPK was defined and operationalized. As part of an international comparison GPK was measured with several complex vignettes. In the present paper, the results of future mathematics teachers’ knowledge from four countries (Germany, South Korea, Taiwan, and the US) with very different teacher-education systems are presented. Significant and relevant differences between the four countries as well as between future teachers at the beginning and at the end of teacher education were found. The results are discussed with reference to cultural discourses about teacher education.  相似文献   
109.
The purpose of this paper is to 1) describe the unique issues of voice patients, ages 21–55; 2) outline the knowledge and clinical skills that speech language pathologists should possess to deal with those issues; and 3) provide suggestions for promoting vocal longevity.  相似文献   
110.
This paper examines the role of uncertainty and risk in determining the optimal commission rates a company should choose for each product of a salesman's product line. We assume that sales for each product are a stochastic function of the time (sales effort) allocated to that product. When sales are assumed to be deterministic, we achieve optimality when each product's commission is the same fraction of its gross margin. However, we determine here that when sales are stochastic this may no longer be true. Optimality conditions require explicit consideration of the utility function of the salesman and the moments of the sales response function.  相似文献   
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