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991.
This paper presents a North-South technology gap model which combines the Schumpeterian approach to technical and structural change with the Keynesian perspective on effective demand and the Balance-of-Payments (BOP) constraint as drivers of growth. Three are the contributions of the paper. First, it develops a model in which the technology gap, relative productivity and relative wages co-evolve and may generate different paths of convergence or divergence between South and North depending on the parameters of the model. Second, the parameters of the model are associated with different types of policies, which allows for discussing how these policies may change the growth path. Finally, the model is used to discuss the contrasting experiences of Asia and Latin America since 1970. Convergence in Asia and divergence in Latin America have been extensively debated topics in the literature on comparative economic development, which highlights the crucial role of industrial policy. It is argued that the results of the technology gap model are consistent with the findings of this literature and helps understand the forces behind convergence and divergence.  相似文献   
992.
Online platforms, from Facebook to Twitter, and from Coursera to Uber, have become deeply involved in a wide range of public activities, including journalism, civic engagement, education, and transport. As such, they have started to play a vital role in the realization of important public values and policy objectives associated with these activities. Based on insights from theories about risk sharing and the problem of many hands, this article develops a conceptual framework for the governance of the public role of platforms, and elaborates on the concept of cooperative responsibility for the realization of critical public policy objectives in Europe. It argues that the realization of public values in platform-based public activities cannot be adequately achieved by allocating responsibility to one central actor (as is currently common practice), but should be the result of dynamic interaction between platforms, users, and public institutions.  相似文献   
993.
Clinical staff members at virtually all college counseling centers provide therapy for victims of sexual misconduct experiences such as sexual assault, sexual harassment, relationship violence, and stalking. A number of college counseling center counselors are also involved in primary, secondary, and tertiary sexual assault prevention efforts. This article develops a model of prevention based on the twin principles of affirmative consent and bystander intervention. We begin with a review of research on sexual assault prevention on campus. We then illustrate this model as it was developed and implemented at a particular institution over the past two decades. We provide effectiveness data in the form of event participation rates, satisfaction measures, and learning outcomes to demonstrate the results of this comprehensive approach. Finally, we end with recommendations for further development of prevention efforts.  相似文献   
994.
This study examined how children’s physical activity levels during recess and lunchtime and the contribution of recess and lunchtime to daily physical activity differed across seasons. Three hundred and twenty-six children aged 8–11 years from Australia participated. Physical activity was measured every 15-seconds using hip-mounted ActiGraph accelerometers for 7 consecutive days during the winter (n = 246), spring (n = 211), summer (n = 161) and autumn terms (n = 139). Data were collected 2012–2013. Time spent in light- (LPA) moderate- (MPA), vigorous- (VPA), and moderate- to vigorous-intensity physical activity (MVPA) during recess and lunchtime were calculated. Longitudinal data were analysed using multilevel analyses and adjusted for potential confounders. The results showed that compared to winter, children engaged in significantly less MVPA and VPA in spring and summer during lunchtime (p < 0.05). No significant changes were observed during recess. The contribution of lunchtime to VPA and MVPA significantly decreased in spring and summer compared to winter (p < 0.05). Children’s lunchtime physical activity levels decreased between winter and spring and summer, with greater declines observed in VPA. Strategies to increase physical activity levels in every season are needed during lunchtime, with a greater emphasis on warmer months.  相似文献   
995.
Looking back over the 50 years since Aerobics was published, I could never have expected for there to have been a major change in physicians’ attitudes toward the value of exercise in the practice of medicine. In my lifetime, I never thought I would see a stress test be considered a mandatory component of a complete examination, inactivity classified as importantly as high blood pressure and high cholesterol, and cigarette smoking considered a coronary risk factor. I have tried in this Research Quarterly for Exercise and Sport (RQES) Lecture presentation to document how this slow but gradual transition took place due to my work and the work of many of my colleagues in this field, along with the important work of The Cooper Institute. In June 1970, I chartered the institute 6 months before I saw my first patient at the Cooper Clinic, but now with the Cooper Center Longitudinal Study being the largest database in the world comparing measured levels of fitness, instead of relying only on questionnaires and correlating fitness and health in our more than 700 published peer-review articles, we have proven and can safely say that “exercise is medicine.” In greater detail, I want this lecture to present what we and others have done in this scientific endeavor, and even the harshest critics are now saying that “these results are too impressive to be ignored.”  相似文献   
996.
Purpose: This study was situated within a longitudinal study of 5 teachers examining the realities of teaching physical education by determining the impact of individual dispositions and contextual factors on the career trajectories of postprimary physical education teachers in Ireland (Iannucci & MacPhail, 2017). One of these participants, Jane, was examined in this study to gain a greater understanding of the realities and tensions experienced by a postprimary teacher enacting 2 distinct sets of role expectations when teaching physical education and another school subject concurrently. Method: Data reported in this article were collected through a semistructured interview and living graph. An interpretative framework was used for analysis, assessing Jane’s perceived meanings of the identified critical incidents in relation to role theory. Results: Teachers timetabled with physical education and another subject concurrently may be expected to navigate and negotiate 2 distinctly different roles within the school community causing difficulty in assuming both roles simultaneously. Short narratives were used to convey 2 themes: (a) role prioritization and (b) role performance. Conclusion: The study results suggest that the already complex and multifaceted role of a school teacher (Richards, Templin, Levesque-Bristol, & Blankenship, 2014) seems to be further complicated when teachers are tasked with simultaneously teaching physical education and another school subject. With the presence of a role conflict management strategy such as role prioritization (Stryker, 1968), one can presume that teachers who are tasked with teaching physical education and another school subject may experience some level of role conflict.  相似文献   
997.
Pressures for change in the field of teacher education are escalating significantly as part of systemic education reform initiatives in a broad spectrum of economically developed and developing nations. Considering these pressures, it is surprising that relatively little theoretical or empirical analysis of learning and change processes within teacher education programs has been undertaken. In this paper, we illustrate some ways in which contemporary socio-cultural learning theory may be used as a lens for addressing these issues. Using a theoretical framework developed by Harré [Harré, R. (1984). Personal being: A theory for individual psychology. Cambridge, MA: Harvard University Press], we show how processes of individual and collective learning led to changes in a teacher education program observed over an eighteen month period of time. Important innovations in program practice were generally found to have their sources in the creative work of individual faculty. However program level changes required negotiation of new ideas and practices within small groups of faculty, and with the larger collective of the program. We conclude that the Harré model, and the socio-cultural learning theories from which it is derived, may offer a useful theoretical framework for interpreting complex social processes underlying organizational renewal, innovation, and change.  相似文献   
998.
We describe a laboratory exercise developed for a cell biology course for second-year undergraduate biology majors. It was designed to introduce undergraduates to the basic molecular biology techniques of Western blotting and immunodetection coupled with the technique of tissue printing in detecting the presence, relative abundance, and distribution of ribulose-1,5-bisphosphate carboxylase in various plant materials. Pre- and postlab surveys indicated significant postlab gains in student understanding of all three lab techniques and relevant lecture topics. Additional postlab survey questions on student perception of the lab modules suggested that the laboratory exercises successfully met a series of pedagogical goals set by the instructors. The combination of these techniques provided a basis for quantitative and qualitative (visual) analysis of a biologically important enzyme and can be applied or modified readily to study other proteins and biological molecules in lab exercises for an introductory cell biology course or molecular biology course.  相似文献   
999.
The history of science should be incorporated into science teaching as a means of improving learning and also to increase the students'' understanding about the nature of science. In biology education, the history of microscopy deserves a special place. The discovery of this instrument not only opened a new and fantastic microworld but also led to the development of one unifying principle of biological sciences (i.e., cell theory). The microscopes of Leeuwenhoek and Hooke opened windows into the microworld of living organisms. In the present work, the knowledge of these themes was analyzed in a group of students beginning an undergraduate biology course. Our data suggest that the history of microscopy is poorly treated at the secondary school level. We propose a didactic activity using a replica of Leeuwenhoek''s microscope made with Plexiglas and a lens obtained from a key chain laser pointer or from a broken CD drive. The proposed activity motivated students to learn about microscopy and helped them to appreciate scientific knowledge from a historical perspective.  相似文献   
1000.
Current concerns about academic plagiarism in student writing assume qualitative and quantitative differences in the writing of students for whom English is a first language (EL1) and English is a second language (EL2), but lack precision in measuring those differences. I examined the citation practices of EL1 and EL2 students in a timed writing proficiency assessment essay by applying Web-Based Interactive ESL Text Evaluation System (WIETES) software to identify borrowed texts by classifying these references in 16 bounding and documenting categories on a Reading Reference Grid. Results showed few differences overall between EL1 and EL2 referencing practices, as all students shared three common weaknesses in citation practice: vague references, patchwriting and confusion of quotes and paraphrases. Moreover, all students seemed to go through four stages in their development of coherent citation practices, although no EL2 students functioned at the highest level of citation practice. Interviews with the students about their referencing practices indicated that both groups claimed ownership of ideas from the source materials which they expressed in their own words, and they cited correctly more often when they had prior knowledge of the topic of the reading. I conclude with a call to administrators of writing assessments to include judgements of bounding and documenting practices in analytic rating scales.  相似文献   
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