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Using triangulation, this study employed two methods to compare whether the responses of early childhood teachers about their use of timeout as a discipline method in focus group discussion was congruent with their behavior from classroom videotapes. The subjects were 5 teachers, who were among a larger group that had participated in one of 6 focus groups and were later videotaped in their preschool classes. These teachers volunteered to be videotaped after they had engaged in the focus groups. In the focus groups, teachers were asked to discuss how they respond to children's misbehaviors and how they make decisions about their responses. The videotapes were subsequently taken during 2 typical mornings in each class. Detailed analyses of the teachers' use or nonuse of time-out as well as their rationale for using this method, were undertaken for both focus group responses and behaviors observed on the videotapes. Results showed that the verbal responses of the teachers were very congruent with what they carried out while teaching.  相似文献   

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Background

Perfluoroalkyl acids (PFAAs) are found globally in wildlife and humans and are suspected to act as endocrine disruptors. There are no previous reports of PFAA levels in adult men from Denmark or of a possible association between semen quality and PFAA exposure.

Objectives

We investigated possible associations between PFAAs and testicular function. We hypothesized that higher PFAA levels would be associated with lower semen quality and lower testosterone levels.

Methods

We analyzed serum samples for levels of 10 different PFAAs and reproductive hormones and assessed semen quality in 105 Danish men from the general population (median age, 19 years).

Results

Considerable levels of perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), and perfluorohexane sulfonic acid were found in all young men (medians of 24.5, 4.9, and 6.6 ng/mL, respectively). Men with high combined levels of PFOS and PFOA had a median of 6.2 million normal spermatozoa in their ejaculate in contrast to 15.5 million among men with low PFOS–PFOA (p = 0.030). In addition, we found nonsignificant trends with regard to lower sperm concentration, lower total sperm counts, and altered pituitary–gonadal hormones among men with high PFOS–PFOA levels.

Conclusion

High PFAA levels were associated with fewer normal sperm. Thus, high levels of PFAAs may contribute to the otherwise unexplained low semen quality often seen in young men. However, our findings need to be corroborated in larger studies.  相似文献   

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PurposeThe specific mechanisms by which peer passengers increase teen drivers' crash risk are not completely understood. We aimed to provide insight on the two primary hypothesized mechanisms, distraction and promotion of risk-taking behavior, for male and female teen drivers and further for select driver–passenger gender combinations.MethodsFrom the National Motor Vehicle Crash Causation Survey (2005–2007), we analyzed a nationally representative sample of 677 drivers aged 16–18 years (weighted n = 277,484) involved in serious crashes, to compare the risk of specific distraction-related and risk-taking–related precrash factors (documented via on-scene crash investigation) for teens driving with peer passengers and teens driving alone.ResultsCompared with males driving alone, those with peer passengers were more likely to perform an aggressive act (risk ratio, RR [95% confidence interval] = 2.36 [1.29–4.32]) and perform an illegal maneuver (RR = 5.88 [1.81–19.10]) just before crashing; risk taking increased regardless of passenger gender. Crash-involved males with passengers were also more likely to be distracted by an exterior factor (RR = 1.70 [1.15–2.51]). Conversely, females with passengers were more often engaged in at least one interior nondriving activity (other than conversing with passengers) (RR = 3.87 [1.36–11.06]), particularly when driving with opposite-gender passengers. Female drivers, both with and without passengers, rarely drove aggressively or performed an illegal maneuver before crashing.ConclusionsPassengers may affect male teen driver crashes through both distraction and risk-promoting pathways, and female involvement primarily through internal distraction. Results of this and future studies investigating peer–driver interactions may guide development of passenger-related crash prevention efforts to complement already existing Graduated Driver Licensing passenger restrictions.  相似文献   

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Objectives: To explore women's attitudes and practices related to douching. Methods: We conducted focus groups between July and December 1999 with 34 black and 27 white women enrolled in a managed care plan in Memphis, Tennessee. Participants were at least 18 years of age and had douched at some time in their lives. Five groups were held with black women and five with white women. Results: The focus groups identified 13 themes that fell in four broad categories: general perceptions about feminine hygiene, douching behavior, factors perpetuating douching, and health information. Each of these categories is briefly discussed with supporting evidence. Conclusions: First, women have deeply-rooted beliefs about the critical role of douching in making them feel clean. Second, douching generally starts at a young age and is reinforced by family, friends, and the media. Third, douching is a very difficult behavior to change; any efforts to influence this behavior must consider women's beliefs and the media marketing efforts that promote douching. Finally, simplistic interventions that only provide risk information about douching are not likely to result in behavior change.  相似文献   

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Abstract

Social workers, supervising students during their field instruction, significantly affect the students' professional competence. This study focuses on the factors causing them to drop out of supervision, on the assumption that an understanding of the phenomenon will enable academia to reduce the turnover by taking appropriate measures to ensure their enduring commitment.

An instrument was developed reflecting the possible reasons, and including questions relating to their experience of supervision. A few more questions were added related to supervisors' level of commitment to student supervision and their satisfaction while they were supervising students in the past. The questionnaire was sent to 83 former supervisors; 63% responded.

The findings show that the main reasons for their drop out were extrinsic; therefore, it is essential to develop a policy of incentives, offering differential rewards related to the supervisors' professional profile.  相似文献   

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No abstract available for this article.  相似文献   

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