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171.
This paper seeks to understand key dimensions of reflection in experience-based workplace learning for research being collaboratively undertaken by scholars in Dutch and US research institutions. We systematically explore and compare Tara Fenwick’s analysis of five perspectives on cognition to distinguish among constructivist, psychoanalytic, situative, critical-cultural, and enactivist perspectives on reflection. Our aim is to examine how to conceptualize reflection so that one or more perspectives can complement our understanding of learning through experience at work. We position reflection not only from a practical but also from a theoretical perspective that moves beyond the individual focus of the constructivist perspective. Fenwick’s five perspectives are described in terms of whether and how reflection is utilized, key activities in the process of reflection, relative focus on the individual and/or the context, triggers for reflection, role of power and positionality, role of emotions, and reflection outcomes. We conclude that adding other lenses to the dominant constructivist perspective helps expand our understanding of reflection as well as identify and attend to other tools, people, and factors in the work situation that influence reflection processes and learning outcomes. The paper closes with a discussion of promising new approaches that have emerged since Fenwick’s analysis.  相似文献   
172.
THE recent British White Paper on post-war education in Englandleaves little doubt that Britain looks to a new era of education.The work has already begun. The British soldier of today willbe the key citizen of tomorrow. Cognizant of this fact, theBritish War Office has established a far-reaching program ofeducation for citizenship among England's troops. It is being carried out by the Army Educational Corps. Thisarticle is the story of their work. Mr. Bickersteth, educated at Christ Church, Oxford, and theUniversity of Paris, is Director of Army Education in the BritishWar Office. He is on leave as Warden of Hart House, Universityof Toronto.  相似文献   
173.
The effect of bioaerosol size was incorporated into predictive dose‐response models for the effects of inhaled aerosols of Francisella tularensis (the causative agent of tularemia) on rhesus monkeys and guinea pigs with bioaerosol diameters ranging between 1.0 and 24 μm. Aerosol‐size‐dependent models were formulated as modification of the exponential and β‐Poisson dose‐response models and model parameters were estimated using maximum likelihood methods and multiple data sets of quantal dose‐response data for which aerosol sizes of inhaled doses were known. Analysis of F. tularensis dose‐response data was best fit by an exponential dose‐response model with a power function including the particle diameter size substituting for the rate parameter k scaling the applied dose. There were differences in the pathogen's aerosol‐size‐dependence equation and models that better represent the observed dose‐response results than the estimate derived from applying the model developed by the International Commission on Radiological Protection (ICRP, 1994) that relies on differential regional lung deposition for human particle exposure.  相似文献   
174.
The use of thimerosal preservative in childhood vaccines has been largely eliminated over the past decade in the United States because vaccines have been reformulated in single‐dose vials that do not require preservative. An exception is the inactivated influenza vaccines, which are formulated in both multidose vials requiring preservative and preservative‐free single‐dose vials. As part of an ongoing evaluation by USFDA of the safety of biologics throughout their lifecycle, the infant body burden of mercury following scheduled exposures to thimerosal preservative in inactivated influenza vaccines in the United States was estimated and compared to the infant body burden of mercury following daily exposures to dietary methylmercury at the reference dose established by the USEPA. Body burdens were estimated using kinetic parameters derived from experiments conducted in infant monkeys that were exposed episodically to thimerosal or MeHg at identical doses. We found that the body burden of mercury (AUC) in infants (including low birth weight) over the first 4.5 years of life following yearly exposures to thimerosal was two orders of magnitude lower than that estimated for exposures to the lowest regulatory threshold for MeHg over the same time period. In addition, peak body burdens of mercury following episodic exposures to thimerosal in this worst‐case analysis did not exceed the corresponding safe body burden of mercury from methylmercury at any time, even for low‐birth‐weight infants. Our pharmacokinetic analysis supports the acknowledged safety of thimerosal when used as a preservative at current levels in certain multidose infant vaccines in the United States.  相似文献   
175.
In chemical and microbial risk assessments, risk assessors fit dose‐response models to high‐dose data and extrapolate downward to risk levels in the range of 1–10%. Although multiple dose‐response models may be able to fit the data adequately in the experimental range, the estimated effective dose (ED) corresponding to an extremely small risk can be substantially different from model to model. In this respect, model averaging (MA) provides more robustness than a single dose‐response model in the point and interval estimation of an ED. In MA, accounting for both data uncertainty and model uncertainty is crucial, but addressing model uncertainty is not achieved simply by increasing the number of models in a model space. A plausible set of models for MA can be characterized by goodness of fit and diversity surrounding the truth. We propose a diversity index (DI) to balance between these two characteristics in model space selection. It addresses a collective property of a model space rather than individual performance of each model. Tuning parameters in the DI control the size of the model space for MA.  相似文献   
176.
In recent years there has been a marked increase in the study of the influence of leadership on creativity, and the effects of this relationship on organizational performance. While a number of explanations have been broached with regard to the positive effects of leadership on creativity, many of these studies propose different, and often contradictory, methods for leaders to achieve these positive effects on creativity within their organizations and work groups. Additionally, little work has been done examining the effects of leadership on highly creative people in fields requiring creativity. The purpose of this study is to examine two existing leadership theories with regard to their viability as models to explain creative performance of eminent scientists. Eminent scientists represent a population of leaders of highly creative individuals in a field that values the production of innovative ideas and products as a marker of performance. Ninety-three excerpts from the biographies of scientists were content coded for leader behaviors and performance criteria. The results of this analysis indicate that a model based on strategic planning and product championing may serve to explain the positive effects of leadership on creativity in a highly creative population.  相似文献   
177.
This study examined antisocial and prosocial behavior of N = 439 adolescent athletes between 14 and 17 years of age (67 teams). Multi‐level analyses showed that team membership explained 20 and 13 percent of the variance in antisocial and prosocial behavior in the sports context, respectively. The team effects suggest that aggregating antisocial or prosocial adolescents within teams may partially explain differences in antisocial and prosocial behavior among athletes in the sports context. A trend was found toward a relation between higher levels of moral reasoning within teams, and less antisocial behavior in the sports context. Favorable moral atmosphere was positively associated with more prosocial behavior in the sports context. Finally, supportive coach–athlete relationships were associated with both less antisocial and more prosocial behavior in the sports context.  相似文献   
178.
The present study investigated whether perception of receiving emotional support mediates the relationship between one partner's giving of emotional support and the other partner's depressive symptomatology using a population-based sample of 423 couples from the Changing Lives of Older Couples study. A path model was used guided by the Actor-Partner Interdependence Model. Results indicated that spouses' giving emotional support was related to the degree to which their spouse reported receiving emotional support. Perception of receiving emotional support, in turn, was related to lower depressive symptomatology of the support recipient. Both husbands and wives can benefit from emotional support through their perception of receiving emotional support, and spouses' perceptions, as well as their actions, should be considered in support transactions.  相似文献   
179.
180.
Two research hypotheses are addressed in this study. (1) Do health trajectories of Hispanics in Utah differ from what has been documented in states with longstanding large Hispanic populations? (2) Do non-Mormon groups in Utah have less favorable health status than Mormons in Utah? This study employs three health outcome measures: activity limitations caused by emotional problems, activity limitations caused by physical problems, and self-rated health status using the 2001 Utah Health Status Survey. Comparisons of Hispanics in their traditional settings within the U.S. generally show more favorable health status for Hispanics than for whites. We find little difference in health status between Hispanics in Utah and their Anglo counterparts. Hispanics were more likely than Anglos to have “a little” activity limitation due to physical problems, but were not more likely to report “a little” or “considerable” activity limitations due to emotional or physical problems. Hispanics and Anglos were statistically equal in probability of self-reported fair to poor health. Important in relation to studies outside of Utah, we find little support for the epidemiologic paradox, the usual finding of more favorable health for Hispanics than for whites. As with ethnicity, we find little difference between non-Mormon and Mormons with respect to health. The most notable exception is that Mormon Hispanics are at a significantly greater risk of emotional problems than Catholic Hispanics in Utah.  相似文献   
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