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Previous studies have compared contraceptive users with nonusers, and pregnant teens with nonpregnant ones. This paper reports the findings of a study of a sample of 119 women aged 21 and under who visited the Young Adult Clinic at Columbia-Presbyterian Medical Center in New York City during 1981. All of these women had been sexually active for a year or longer, but had never been pregnant. The expectation that such a sample would include mainly consistent users of contraception was unwarranted; within this special population were found young women who had never used contraception or who had only been sporadic users, as well as the consistent users. Moreover, there are many more similarities than differences among these groups, and their stated motivations for not becoming pregnant are the same. The consistent contraceptors were more likely to live with their mothers, to have mothers who worked, to indicate that their parents would help them have an abortion, and to indicate they would have an abortion should they become pregnant. The similarities between these young women are very important for programs, which often rely heavily on stated motivation or even on a clinic visit as evidence that a young woman intends to use a birth control method. There is nothing here to support this simple view. Instead the notion is substantiated that many adolescents may lack cognitive consistency on this subject or may lack the future orientation to be effective contraceptive users. 相似文献
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The authors describe three accidental deaths resulting from occupational hazards involving environmental gas alterations. One involved the displacement of oxygen caused by leakage of liquid nitrogen during the installation of a magnetic resonance imaging system. Two involved elevated environmental carbon dioxide concentrations: dry ice sublimation in a walk-in refrigerator in a research laboratory, and activation of a carbon dioxide fire alarm-extinguisher system by a woman locked in a bank vault. The autopsy findings, scene investigations, and certifications of these deaths, as related to the mechanisms of death, are discussed. 相似文献
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Abramson and Inglehart find a significant trend toward postmaterialist values in Western Europe, which they argue is largely driven by the gradual processes of generational replacement. Clarke, Dutt, and Rapkin argue that this trend is a methodological artifact of the wording of Inglehart's four-item measure of materialist/ postmaterialist values. They claim that because this battery does not include a question about unemployment, in periods of high unemployment respondents tend to choose postmaterialist goals. The long-term trend toward postmaterialism in Western Europe, they argue, results from rising levels of unemployment during the past two decades. Abramson and Inglehart point out that increases in inflation have a short-term impact on decreasing postmaterialism, but maintain that the positive relationship between unemployment and postmaterialism is spurious. As this analysis shows, Clarke, Dutt, and Rapkin find a positive relationship between unemployment and postmaterialism by building a model that has little theoretical justification and that is not robust to changes in specification. As this analysis demonstrates, unemployment is actually linked with support for materialist goals, and the trend toward post-materialism is robust in the face of alternative time frames, models, and specifications. The weight of the evidence demonstrates that the long-term trend toward postmaterialism in Western Europe is driven by generational replacement. 相似文献
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Susan J. Popkin James E. Rosenbaum Patricia M. Meaden 《Journal of policy analysis and management》1993,12(3):556-573
This article reports on a highly unusual experiment in racial and economic integration, the Gautreaux program. This program helps black families who are either current or former residents of public housing move into subsidized housing in Chicago and its suburbs. Surveying a random sample of 332 participants, we find that suburban movers are significantly more likely to have a job post-move than city movers, even among those who had never had a job before moving. Multivariate analysis shows that these differences are significant even after controlling for respondents' previous work history, human capital, and personal characteristics. These results suggest that low-income urban blacks experience significant gains in employment by moving to middle-class suburbs. Thus, housing assistance may be an effective alternative to traditional welfare-to-work programs. 相似文献
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An accurate and simple method was developed to determine the level of toluene in urine and blood quantitatively by using the gas chromatography/mass spectrometry (GC/MS) with headspace--solid phase microextraction (HS-SPME) technique. An assembly of SPME with a replaceable extraction fiber, coated with 100 microm polydimethylsiloxane, was used. The detection limit of toluene in blood and urine with HS-SPME technique was 10 times higher than that with headspace (HS) technique. To compare the HS-SPME with HS technique for the determination of toluene in biological fluids, blood and urine samples from glue sniffers were analyzed by both methods. The level of toluene by the two techniques was highly correlated: the correlation coefficient (r2) between the two sets of values were 0.98 and 0.96 in urine and blood, respectively. 相似文献