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Research on social networks and innovation emphasizes that individuals spanning structural holes and crossing institutional boundaries have more opportunities for knowledge recombination and innovation involvement. However, transforming the potential knowledge and resources available through personal networks to attain innovation can be difficult for the focal individual. Using an ego-network approach, this study examines whether and to what extent an individual strategic orientation to cooperation (i.e. tertius iungens) contributes to strengthening the relation between two personal network properties (structural and institutional separation) and involvement in innovation. Our analysis is conducted in the context of biomedicine, where research networks are particularly relevant for science and innovation achievements. Our findings advance social network theory by decoupling social network mechanisms from individual strategic networking behavior as factors influencing knowledge generation processes. Results also provide original evidence on an overlooked phenomenon: the moderating role of a tertius iungens orientation in the relationship between multiple social network properties and innovation. Finally, our research sheds new light on the distinct sources of knowledge recombination in networks and the role of individual networking strategies to facilitate mobilization of resources for innovation.  相似文献   
84.
Schools in the most deprived areas in Brazil are marked by extreme poverty, a situation that has obvious consequences for the everyday life in schools and for efforts to develop a supportive culture of schooling. Nevertheless, schools’ responses to poverty are far from uniform. Although the context of poverty generally determines what is possible for schools to achieve, this context is by no means consistent. Not all schools located in poor areas offer poor education. And, in themselves, unfavourable contexts do not necessarily generate educational failure. This article captures the diversity of effects generated by poverty at the school level, and the variety of responses by schools situated in very similar socioeconomic and cultural contexts. It draws on a study conducted in the state of Minas Gerais, which explored five schools and their corresponding cultures to reveal the diverse effects of poverty at the school level.  相似文献   
85.
Journalism     
Howard Simons and Joseph A. Califano, Jr. (eds.) The Media and the Law (New York: Praeger Special Studies, 1976---$4.95, paper with hardbound edition available)

Oscar H. Gandy, et al. Media and Government: An Annotated Bibliography (Institute for Communisation Research, Stanford University, Stanford, Calif. 94305--- apparently free on request, paper)

George S. Rage, et al. New Strategies for Public Affairs Reporting: Investigation, Interpretation, and Research (Englewood Cliffs, N.J.: Prentice-Hall, 1976---price not given)

William A. Lucas and Karen B. Possner's Television News and Local Awareness: A Retrospective Look (Santa Monica, Calif.: Rand Corp. R-1858-MF, 1975---$5.00, paper)

Judith S. Gelfman's Women in Television News (New York: Columbia University Press, 1976---$7.95)  相似文献   
86.
This short communication is a discussion of the paper entitled “Adaptive sliding-mode-observer for sensorless induction motor drive using two-time-scale approach” by A. Mezouar, M.K. Fellah and S. Hadjeri published in the Simulation Modelling Practice and Theory 16 (2008) 1323–1336. In the discussed paper the authors present a current and flux sliding mode observer for the induction motor that also incorporates an adaptive laws in order to estimate the rotor speed and the inverse of the rotor time constant. However the proposed design for the observer and for the adaptive laws, employs the real value of the rotor time constant and the real value of the rotor speed, which are unknown, and therefore cannot be used in the observer design nor in the adaptive laws design.  相似文献   
87.
The aim of this study was to estimate the contribution of experience, body size and maturity status to variation in sport-specific skills of adolescent soccer players. The participants were 69 players aged 13.2?–?15.1 years from three clubs that competed in the highest division for their age group. Height and body mass were measured and stage of pubic hair development was assessed at clinical examination. Years of experience in football was obtained at interview. Six football skill tests were administered: ball control with the body, ball control with the head, dribbling with a pass, dribbling speed, shooting accuracy and passing accuracy. Multiple linear regression analysis was used to estimate the relative contributions of age, stage of sexual maturity, height, body mass and years of formal training in soccer to the six skill tests. Age, experience, body size and stage of puberty contributed significantly but in different combinations to the variance in four of the six skill tests: dribbling with a pass (21%; age, stage of maturity), ball control with the head (14%; stage of maturity, height, body height × body mass interaction), ball control with the body (13%; stage of maturity, years of training) and shooting accuracy (8%; stage of maturity, height; borderline significance, P?=?0.06). There were no significant predictors for the tests of dribbling speed and passing accuracy. In conclusion, age, experience, body size and stage of puberty contributed relatively little to variation in performance in four of the six soccer-specific skill tests in adolescent footballers aged 13?–?15 years.  相似文献   
88.
This study examined whether exposure to changes in peer aggression predicted changes in child physical aggression (PA) in preschool children attending Norwegian Early Childhood Education and Care (ECEC) centers. Data from the Behavior Outlook Norwegian Developmental Study were used, including 956 children. In fixed effects models, within-child changes in exposure to peer aggression predicted changes in teacher-rated child PA across ages 2, 3, and 4. Moreover, changes in exposure to a peer group with two or more externalizing children increased teacher-rated child PA over time, but only for boys. No significant peer effects on parent-rated child PA were found. Findings point to the importance of avoiding the congregation of several problematic children, particularly boys, in the same ECEC groups.  相似文献   
89.
Background: Many medical schools require a student thesis before graduation. Publishing results in a peer‐reviewed journal could be an indicator of scientific value and acceptability by the scientific community. The publication pattern of theses published by medical students in Peru is unknown. The aim of this study was to assess the characteristics and publication pattern of theses in biomedical‐indexed journals conducted by medical students in a university with the highest research output in Peru. Methods: Data from registered theses between 2000 and 2003 were obtained from the university library. Publication of theses in biomedical journals was assessed in 2008 by a search strategy using PubMed, Google Scholar, LILACS, LIPECS and SciELO. Results: Four hundred and eighty‐two medical theses were registered between 2000 and 2003; 85 (17.6%) were published in biomedical‐indexed journals. Of the published theses, 28 (5.8%) were published in MEDLINE‐indexed journals, 55 (11.4%) in SciELO‐indexed journals, 61 (12.6%) in LILACS‐indexed journals and 68 (14.1%) in LIPECS‐indexed journals. Most of the published theses (80%) were in Spanish and published in Peruvian journals; and 17 theses (20%) were published in foreign journals (all of them indexed in MEDLINE). In addition, 37 (43.5%) belong primarily to internal medicine, and 24 (28.2%) belong primarily to infectious diseases. Medical students were first authors in 71 (83.5%) of the articles. Conclusion: In this study, most of the published theses were in Spanish, published in local journals and indexed in LIPECS. The percentage of published theses in biomedical journals at this university is comparable with others coming from developed countries.  相似文献   
90.
The dominant paradigm in Archival Science, thehistorical-technicist paradigm, has its origins with the French Revolution and raised from the social, economic, political, ideological and cultural changes that occur during the 19th and 20th centuries. During this last one and due specially to the technological revolution Archival Science reinforced its technical component and became autonomous in face of History, but the consolidation of the model, based on a custodial, technicist and documentalist perspective, is associated to a knowledge essentially empirical. By effect of the new conditions generated by Information Society, the dominant paradigm entered into a crisis and developed inside itself the factors which, unavoidably, will produce the paradigm shift. The new paradigm — thescientific-informational paradigm — conceives Archival Science as an applied discipline into the scope of Information Science and defines unequivocally its object of study — the archive, understood as aninformation system — and its scientific method of research. The method tends to find consolidation through quadripolar research dynamics, which is operated and continuously repeated within the field of knowledge itself, which implies a permanent interaction on four poles — epistemological, theoretical, technical and morphological.  相似文献   
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