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491.
492.
In addition to consistent use, condoms must be used correctly. The purpose of this study was to identify prevalence and types of condom-associated discomfort among university students, the outcomes of this discomfort, and the role of discomfort in condom breakage. We conducted a cross-sectional study of 206 students attending a private university in the southern United States. We assessed 3 potential outcomes: breakage, not using condoms throughout sex, and low condom-use motivation. Nearly one third reported discomfort, including tightly fitting condoms, vaginal irritation, and loss of sensation. Discomfort was associated with breakage (p = .0001), incomplete use (p = .0001), and less motivation to use condoms (p = .018). Gender moderated the latter 2 findings. Adjusted findings indicate that students reporting discomfort were 3.6 times more likely to also report breakage (p = .0009). Continued investigation of this topic is warranted. Prevention education may benefit university students by promoting several key practices, such as adding lubricant to condoms before they dry out and acquiring condoms that fit properly.  相似文献   
493.
For the past several years, the EPA has been monitoring clinical studies on the adverse health effects of heart patients' exposure to carbon monoxide. This paper examines the impact of three such studies (including the multi-center CO study organized by the Health Effects Institute) on the forthcoming EPA standards for carbon monoxide. Eleven peer-nominated specialists with expertise in environmental science and public policy were interviewed according to a specific protocol. Overall, the experts felt that the HEI study would receive greater weight than the other two studies in the regulatory process for a variety of technical reasons. Weighting each expert opinion equally, we conclude that there is about a 0.69 probability that the CO standards will be retained at their present levels, a 0.28 probability that the standards will be tightened, and a 0.03 probability that the standards will be relaxed. When asked to imagine that the HEI data were never collected and then asked to reassess their probability judgments, the mean probability judgment that the standards will be relaxed rose to 0.11, while the mean probability judgment that the standards will be tightened fell to 0.20. A modest degree of variability in expert opinion is reported in the paper. While the HEI study may receive relatively great weight in the regulatory process, it increases only slightly the probability that EPA's CO standards will be changed.  相似文献   
494.
Japanese direct investment is assuming an increasing importance in the U.K. economy, especially in the manufacturing sector where Japanese management and manufacturing techniques have aroused particular interest. Until recently this investment in manufacturing has been primarily restricted to plants of an assembly-based nature and Japanese companies have sought out labour markets which best satisfy the needs of this type of operation. However, early signs are appearing which suggest that new Japanese manufacturing investment is becoming increasingly sophisticated. In the light of this emergent trend, this paper uses recent research to draw attention to the labour market problems that are likely to occur as the skill requirements of Japanese employers increase. The paper then concludes by discussing strategies which individual firms should adopt to protect themselves from any consequent labour market disruption.  相似文献   
495.
Ergonomics: The Physiotherapist in the Workplace Edited by Margaret I. Bullock, Churchill Livingstone, Edinburgh (1990), pp. xviii + 332, 14.95 (soft), ISBN 0-443-03612-8.  相似文献   
496.
497.
This paper is one of a series in which experienced therapists were invited to outline their approach to marital therapy — Editor.  相似文献   
498.
499.
We examine changes over the 1980s in the effect of child support payments on the educational attainment of children age 16 to 19 in the United States, and why child support has a stronger impact than other sources of income. We use 1979 and 1988 Current Population Survey data, covering a period when improvements in enforcement should have increased the proportion of reluctant fathers paying support. We hypothesize and find that the positive effect of child support on education diminished somewhat over this period, both absolutely and in relation to other income.  相似文献   
500.
This paper gives a method for decomposing many sequential probability ratio tests into smaller independent components called “modules”. A function of some characteristics of modules can be used to determine the asymptotically most efficient of a set of statistical tests in which a, the probability of type I error equals β, the probability of type II error. The same test is seen also to give the asymptotically most efficient of the corresponding set of tests in which a is not equal to β. The “module” method is used to give an explanation for the super-efficiency of the play-the-winner and play-the-loser rules in two-sample binomial sampling. An example showing how complex cases can be analysed numerically using this method is also given.  相似文献   
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