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991.
In a scientific dispute over the effects of atrazine on amphibians, chemical industry–funded and publically funded scientists present stunningly contrasting constructions of atrazine's environmental concentrations, persistence, and potential to harm. Considerable scientific uncertainties and variable ranges allow authors to construct preferred versions of the story of atrazine. These incommensurate rhetorical constructions, more the result of competing economic and environmental interests than of any paradigmatic misalignments, have prolonged the dispute not only over atrazine's effects but also over whether its sales should be banned.  相似文献   
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Objective: To analyze the possible dose-response association between components of sports participation (intensity, volume and previous engagement) and 4-year mortality rates among Brazilian adults.

Methods: 679 males and females (mean age among men = 66.7 ± 9.3 years old and mean age among women = 64.8 ± 8.9 years old) composed the study sample. Sports participation was assessed using Baecke’s questionnaire, which considers intensity, duration and previous engagement. Medical records were used to identify the cause of the death. Cox regression analysis was performed to determine the independent associations of exercise components and mortality.

Results: Participants that reported exercising at moderate-vigorous intensity (Moderate/vigorous: 4.1% versus None/light: 10.3% [p-value = 0.012]; HR = 0.42 [0.1 to 0.94)] and for more than four months (≥4 months: 5.3% versus <4 months: 10.2% [p-value = 0.038]; HR = 0.47 [0.24 to 0.94]) had lower mortality risk. The percentage of survival according to all-cause mortality was significantly higher for participants engaged in sports at moderate-vigorous intensity (p-value = 0.014), as well as for those engaged in sports for periods superior than four months (p-value = 0.036).

Conclusion: We found higher percentage of survival among adults engaged in sports at moderate-vigorous intensity and with at least four months of previous engagement.  相似文献   

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In this essay, Jennifer Morton discusses educators as central examples of agents who engage in ideal and nonideal ways of thinking. The educator, as a representative of the political community, is tasked with two aims. The first is nurturing students with the skills and knowledge they need for the world as they will find it. In pursuing this goal, the educator is assuming certain social facts, some of them unjust, that constitute the present nonideal world. The second aim is civic — educating future citizens. Insofar as the educator is involved in pursuing this goal, his or her role is to work at making certain future social facts true, in the hope of making the future slightly more ideal. Morton argues that if we think of these two aims instrumentally, they can come into conflict. She does not suggest a resolution to this conflict, but rather develops an alternative expressive account of the civic role of the educator. Ideal thinking by educators, Morton maintains, should be thought of as constituting an expression of respect toward their fellow citizens here and now. Ultimately, she argues that this expressive component of the educator's job is crucial to the educator's role in the political community.  相似文献   
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N. Mukunda 《Resonance》2011,16(9):796-797
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There remains significant confusion surrounding the purpose, audience, and proposed application of the Framework for Information Literacy for Higher Education. This exploratory study addresses the question of whether undergraduate students can understand the language and concepts in this document. By presenting student responses to pretest questions recorded at the beginning of a semester-long research methods course, this article shows that students can, even on first impression, begin to make sense of the complexity and richness found in the Framework for Information Literacy for Higher Education.  相似文献   
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