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21.
Serum testosterone and cortisol levels were measured by radioimmunoassay in 14 young male judo competitors, in samples taken 10 minutes before and 45 minutes after two different procedures. The first involved physical exercise and the second competitive fighting. Both procedures were of 5 minutes duration and sessions took place at the same time (between 10:00 A.M. and 12:00 P.M. local time) but on different days. Comparing the two situations over all subjects revealed that testosterone increased after exercise and decreased slightly after Competition. Between subject comparisons suggested that contrary to previous claims, winning or losing did not significantly change the testosterone and cortisol levels. Comparisons of subjects who were members of the Regional Team with individuals who were not part of that group confirmed that members increased their testosterone levels after competition, whereas the nonmembers showed a significant decrease. Moreover, success of the individuals, in their sporting record, correlated positively and significantly with the changes of testosterone observed during the competition. These preliminary results suggest that previous personal experience of success can influence the pattern of the psychoendocrine response to a contest situation. 相似文献
22.
The purpose of this study was to determine the effects of teacher feedback delivered via a public address system on the off-task behavior of elementary-school physical education students. A multiple baseline design across three classes was used in this investigation. Results indicated a consistent decline in off-task behavior when the public address feedback system was used. 相似文献
23.
Beyond bruises and broken bones: the joint effects of stress and injuries on battered women's health
We investigated the joint mediating effects of injuries and stress on the relationship between abuse and women's health. A community sample of 397 women, half of whom had been assaulted by an intimate partner within the prior 6 months, was interviewed about their experience of intimate partner violence, injuries, stress, income, depression, and physical health problems. Structural equation modeling techniques confirmed the complex model of hypothesized indirect effects of abuse on women's physical health problems through injuries, stress, and depression. Stress accounted for 80% of the indirect effect of abuse on women's physical health. Its direct effect on physical health was somewhat larger than its indirect effect through depression, but both processes played a key role in determining the effect of abuse on women's physical health problems. Furthermore, abuse was a stronger predictor of women's stress than was poverty. Implication and future research are discussed. 相似文献
24.
Few studies have been published on the attitudes of people with physical disabilities toward genetic counseling and prenatal diagnosis. Articles in the lay press and social science literature on this topic, mainly written by disability rights activists and advocates, imply opposition to prenatal diagnosis and the field of clinical genetics by the physically disabled population. In this study, 15 adults with physical disabilities were interviewed regarding their attitudes toward genetic counseling and prenatal diagnosis. Genetic counseling and prenatal diagnosis were generally viewed favorably by this sample of the disability community. Only a small percentage of the sample perceived genetics to be eugenic. Implications for genetic counseling and future research are discussed. 相似文献
25.
Scientific misconduct includes the fabrication, falsification, and plagiarism (FFP) of concepts, data or ideas; some institutions
in the United States have expanded this concept to include “other serious deviations (OSD) from accepted research practice.”
It is the absence of this OSD clause that distinguishes scientific misconduct policies of the past from the “research misconduct”
policies that should be the basis of future federal policy in this area. This paper introduces a standard for judging whether
an action should be considered research misconduct as distinguished from scientific misconduct: by this standard, research
misconduct must involve activities unique to the practice of science and must have the potential to negatively affect the
scientific record. Although the number of cases of scientific misconduct is uncertain (only the NIH and the NSF keep formal
records), the costs are high in terms of the integrity of the scientific record, diversions from research to investigate allegations,
ruined careers of those eventually exonerated, and erosion of public confidence in science. Existing scientific misconduct
policies vary from institution to institution and from government agency to government agency; some have highly developed
guidelines that include OSD, others have no guidelines at all. One result has been that the federal False Claims Act has been
used to pursue allegations of scientific misconduct. As a consequence, such allegations have been adjudicated in federal courts,
rather than judged by scientific peers. The federal government is now establishing a first-ever research misconduct policy
that would apply to all research funded by the federal government regardless of which agency funded the research or whether
the research was carried out in a government, industrial or university laboratory. Physical scientists, who up to now have
only infrequently been the subject of scientific misconduct allegations, must nonetheless become active in the debate over
research misconduct policies and how they are implemented since they will now be explicitly covered by this new federal wide
policy.
Disclaimer: The authors are grateful for the support for conduct of this research provided by the United States Department of Energy
(DOE). The views expressed in this paper are solely those of the authors and were formed and expressed without reference to
positions taken by DOE or the Pacific Northwest National Laboratory (PNNL). The views of the authors are not intended either
to reflect or imply positions of DOE or PNNL. 相似文献
26.
This study investigated whether the perception of self as socially rejected might contribute to increased physical aggression among elementary-school children. It was hypothesized that physically aggressive children would become more physically aggressive over time if they perceived that they were rejected and tended to blame peers for social failure experiences. Third-grade boys and girls (n = 941) were assessed in the Fall and Spring of the school year. Peer-report data on physical aggression and social preference were collected, along with self-report data on perceived rejection and attributions for social failure experiences. Results for boys were consistent with hypotheses, whereas the results for girls revealed a different pattern of relations. These results constitute prospective evidence that children's self-perceptions of social rejection can uniquely influence externalizing behavior. Results are discussed in terms of mechanisms that might mediate the relation between perceived rejection and physical aggression. 相似文献
27.
Algebras of Intervals and a Logic of Conditional Assertions 总被引:1,自引:0,他引:1
Intervals in boolean algebras enter into the study of conditional assertions (or events) in two ways: directly, either from intuitive arguments or from Goodman, Nguyen and Walker's representation theorem, as suitable mathematical entities to bear conditional probabilities, or indirectly, via a representation theorem for the family of algebras associated with de Finetti's three-valued logic of conditional assertions/events. Further representation theorems forge a connection with rough sets. The representation theorems and an equivalent of the boolean prime ideal theorem yield an algebraic completeness theorem for the three-valued logic. This in turn leads to a Henkin-style completeness theorem. Adequacy with respect to a family of Kripke models for de Finetti's logic, ukasiewicz's three-valued logic and Priest's Logic of Paradox is demonstrated. The extension to first-order yields a short proof of adequacy for Körner's logic of inexact predicates. 相似文献
28.
Wolff P 《Cognition》2003,88(1):1-48
29.
Sjoerd L. Bonting 《Zygon》1999,34(2):323-332
Comparison of the concepts of creation from chaos and creation out of nothing ( creatio ex nihilo ) leads me to reject the latter for several reasons: it is not the biblical concept, and it presents serious conceptual, scientific, and theological problems. Chaos theology is outlined under the headings creation from chaos; chaos and contingency; chaos, evil, and creativity; chaos and incarnation; chaos and eschatology. It is shown to be well suited for the science-theology dialogue by some examples of its application to aspects of cosmic and biological evolution: initial mystery, separation and ordering; chaos and entropy; contingency and fine-tuning of the universe; purpose and progressiveness in evolution; and complexity theory and chaos events. 相似文献
30.
David B. Suits 《Argumentation》1999,13(2):127-138
In recent philosophical debates a number of arguments have been used which have so much in common that it is useful to study them as having a similar structure. Many arguments – Searle's Chinese Room, for example – make use of thought experiments in which we are told a story or given a narrative context such that we feel we are in comfortable surroundings. A new notion is then introduced which clashes with our ordinary habits and associations. As a result, we do not bother to investigate seriously the new notion any further. I call such an arrangement, which is perhaps a variation of the fallacy of presumption, a Steep Cliff argument. One remedy for the misdirection of a Steep Cliff argument is to tell a counterstory from the point of view of the rejected notion. 相似文献