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161.
The learning cycle is a method of teaching—it is also a curriculum organization principle and is derived directly from the mental functioning model invented by Piaget. Although Jean Piaget contributed to the formation of the learning cycle (Piaget, 1973), its present structure has to be attributed to Dr. Robert Karplus and the persons who developed the materials of the Science Curriculum Improvement Study (SCIS). It was through the SCIS activities that many of us learned how to develop curricula and teach with the learning cycle. The learning cycle is built upon the premise that three distinct phases are necessary in developing understanding of a concept, that those phases have a definite sequence, and each phase has a definite structure or form. The research done in testing the form variable has already been reported in this journal (Renner, Abraham, & Birnie, 1985). This report explores whether or not each learning-cycle phase is necessary in learning a concept. 相似文献
162.
Objective: To investigate the effect of interleukin-18 (IL-18) on immune response induced by plasmid encoding hepatitis B virus middle protein antigen and to explore new strategies for prophylactic and therapeutic HBV DNA vaccines. Methods: BALB/c mice were immunized with pCMV-M alone or co-immunized with pcDNA3-18 and pCMV-M and then their sera were collected for analysing anti-HBsAg antibody by ELISA; splenocytes were isolated for detecting specific CTL response and cytokine assay in vitro. Results: The anti-HBs antibody level of mice co-immunized with pcDNA3-18 and pCMV-M was slightly higher than that of mice immunized with pCMV-M alone, but there was not significantly different (P>0.05). Compared with mice injected with pCMV-M, the specific CTL cytotoxity activity of mice immunized with pcDNA3-18 and pCMV-M was significantly enhanced (P<0.05) and the level of IFN-γ in supernatant of splenocytes cultured with HBsAg in vitro was significantly elevated (P<0.05) while the level of IL-4 had no significant difference (P>0.05). Conclusion: The plasmid encoding IL-18 together with HBV M gene DNA vaccines may enhance specific TH1 cells and CTL cellular immune response induced in mice, so that IL-18 is a promising immune adjuvant. 相似文献
163.
Summary The paper focuses upon curriculum planning in the scientific disciplines at university level, although it is claimed the argument
may be of wider applicability. Drawing upon the writings of philosophers of education from several decades ago (notably Schwab and Scheffler) whose work is too often overlooked in contemporary debates about the curriculum, and using illustrative examples from the
author’s own experience, it is argued that too often the focus of science curriculum planning is the “rhetoric of conclusions”
or the “substantive structure” — the current state of knowledge at the forefront of the respective disciplines — to the neglect
of what Schwab called the “syntactical structure” of the sciences (which roughly approximates their epistemology). This aspect of these
disciplines is essential for the general student trying to become familiar with the nature of science as a broad field of
knowledge, for prospective teachers, and — contra Scheffler’s view — for students who aim at careers as researchers.
“When walking in quicksand country, carry a stout pole — it will help you get out should you need to. As soon as you start to sink, lay the pole on the surface of the quicksand. Flop onto your back on top of the pole. Work the pole to a new position: under your hips and at right angles to your spine. Take the shortest route to firmer ground, moving slowly.” Piven/Borgenicht 1999, p. 18
This paper was presented at the conference Silence Between the Disciplines, Berlin-Brandenburg Academy of Sciences, Berlin, October 2002. 相似文献
Zusammenfassung Der Beitrag der Epistemologie zur Curriuculumkonstruktion in den Naturwissenschaften Der Aufsatz fokussiert auf die Curriculumplanung für den naturwissenschaftlichen Unterricht in der universit?ren Lehrerausbildung, wenngleich behauptet wird, dass dieses Argument weitreichendere Anwendbarkeit besitzt. Der Text knüpft an erziehungswissenschaftlichen Schriften (insbesondere von Schwab und Scheffler) an, deren Ver?ffentlichung zwar einige Dekaden zurückliegt, deren Beitrag in den aktuellen Debatten aber oft übersehen wird. Darüber hinaus werden einige illustrative Beispiele aus dem Erfahrungsschatz des Autors genutzt, um zu zeigen, dass der Fokus der Curriculumplanung für die Naturwissenschaften — dem augenblicklichen Wissensstand der zu berücksichtigenden Disziplinen zufolge — zu oft in einer „Rhetorik der Schlussfolgerung“ oder „substantivischen Struktur“ besteht, was dazu führt, dass das, was Schwab die „syntaktische Struktur“ der Naturwissenschaften nennt (und ihrer Epistemologie ziemlich nahe kommt), vernachl?ssigt wird. Dieser Aspekt jener Disziplinen ist besonders wichtig für Studierende, die allgemeinbildend vertraut werden m?chten mit den Naturwissenschaften, für angehende Lehrer und — entgegen Schefflers Ansicht — für Studenten, die eine Karriere als Forscher anstreben.
“When walking in quicksand country, carry a stout pole — it will help you get out should you need to. As soon as you start to sink, lay the pole on the surface of the quicksand. Flop onto your back on top of the pole. Work the pole to a new position: under your hips and at right angles to your spine. Take the shortest route to firmer ground, moving slowly.” Piven/Borgenicht 1999, p. 18
This paper was presented at the conference Silence Between the Disciplines, Berlin-Brandenburg Academy of Sciences, Berlin, October 2002. 相似文献
164.
165.
In Grutter vs. Bollinger, the U.S. Supreme Court ruled that the use of race as one factor, among many in admissions decisions is constitutional. It is not known, however, whether future legal opinions will continue to uphold the use of affirmative action policies. Some have argued that class-based preferences can achieve many of the same goals as in affirmative action while being more likely to withstand legal challenges. To date, no empirical studies have been conducted on the potential impact of a class-based admissions policy if implemented at an undergraduate institution. This paper reports on a study at a selective public college and compares a number of outcomes under three admissions models: the original admissions decisions, a purely academic model, and an socio-economic status (SES)-based model. The findings showed that use of the SES-based model would have led to a more academically qualified class than in the original admitted class while maintaining substantially greater student diversity that was found under the academic model. An admissions policy based on preferences for socio-economically disadvantaged applicants appears to hold promise for other colleges and universities with similar institutional and applicant characteristics. The ideas and research design reported in this paper are based on the doctoral dissertation study of the second author, Undergraduate Admissions Models Incorporating Socioeconomic Factors (Johnson, 2000). 相似文献
166.
Theories of adolescent connectedness suggest that adolescents strive to become connected by engaging with and valuing the
people, activities, and worlds in their social ecology. The purpose of this study was to examine the psychometric properties
of a measure designed to assess these worlds of connectedness among 320 junior high school students in Taiwan. The subscales
and composite scales evidenced satisfactory reliability and concurrent validity. A hypothesized three-factor, higher order
structural model of connectedness was cross-validated. Girls were generally more connected than boys. Both connectedness to
school and to friends explained more variance in connectedness to self than did family connectedness. There was mixed support
for separation-individuation processes. The measure appears promising in terms of future research on adolescent social development
in the Asia Pacific. 相似文献
167.
168.
169.
This article attempts to characterize the general problem of selecting methods for decision-making. The traditional rational approach to choice is from economics, which offers expected-value maximization. The task environment of decision method selection, however, does not seem to provide the data necessary for carrying out the expected-value calculations. Our approach uses methods from the field of cognitive science. We develop the notion of domain size in fields such as chess, borrowing the concept of a chunk from human memory. We then develop a heuristic rule for choiceamongmethods. We propose this rule as one of many possible rules. 相似文献
170.