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121.
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
122.
123.
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
124.
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
125.
126.
Distributive and Procedural Justice in Seven Nations 总被引:1,自引:0,他引:1
The paper examines the impact of distributive justice and procedural justice variables on judgments in seven countries (Bulgaria, France, Hungary, Poland, Russia, Spain, and the United States). Subjects were presented with each of two experimental vignettes: one in which the actor unsuccessfully appeals being fired from his job and one in which the actor unsuccessfully goes to an employment agency to seek a job; they were asked to rate the justness of the outcome and how fairly the actor had been treated. The vignettes manipulated deservingness and need of the actor (distributive justice factors) and impartiality and voice in the hearing (procedural justice factors). Four hypotheses were tested: first, a distributive justice hypothesis that deservingness would be more important than need in these settings; second, a procedural justice hypothesis that the importance of voice and impartiality vary depending on the nature of the encounter and the forum in which it is resolved; third, because of their recent socialist experience, Central and Eastern European respondents make greater use of need information and less use of deservingness information than Western respondents; and fourth, that distributive justice and procedural justice factors interact. The distributive justice hypothesis is supported in both vignettes. The procedural justice hypothesis receives some support. Impartiality is more important in the first vignette and voice is more important in the second vignette. The interaction hypothesis was not supported in the first vignette, but does receive some support in the second vignette. The cultural hypothesis is not supported in either vignette. The implications for distributive and procedural justice research are discussed. 相似文献
127.
The present study investigated the effect on witness confidence and accuracy of confusing questions often used by attorneys in court. Participants viewed a videotaped film and were individually questioned about the incident 1 week later. Half the participants were asked questions using six categories of confusing questions (negatives, double negatives, leading, multiple questions, complex syntax, and complex vocabulary); the remaining half were asked for the same information using simply phrased equivalents. Confusing questions reduced participant-witnesses' accuracy and suppressed confidence–accuracy relationships compared with the condition where simplified alternatives were asked. Witness performance was impaired by the fact that mock-witnesses rarely asked for a confusing question to be explained or qualified their answers. This experiment demonstrates the importance of ensuring that lawyers ask witnesses simple, clear, questions. 相似文献
128.
A biomechanical study of the human vertebral artery with implications for fatal arterial injury 总被引:8,自引:0,他引:8
We studied the biomechanical behaviour of ring and strip specimens from along the length of 18 vertebral arteries taken from 16 subjects aged 28-90 years, in order to consider some of the factors which may play a role in vertebral artery rupture. The method was chosen to allow a comparison between circumferential distension (ring samples) and longitudinal extension, (strip samples). The samples were extended between the jaws of a tensile testing apparatus until the specimen broke and a number of biomechanical parameters were derived. These were the percentage extension to break, the tensile strength, Young's modulus and the peak load. There were a number of important findings. The vertebral artery was shown to be susceptible to longitudinal stretching with a number of strip samples breaking when extended by as little as 16-20%. The tensile strength and load at peak of the strip specimens were correspondingly lower than for the ring samples. Marked intersubject variations were shown for all these parameters and prominent changes in behaviour occurred along the vertebral artery. This study indicates that the artery may be susceptible to head and neck movements which cause the vessel to stretch, and intersubject variations in behaviour may be one important explanation for the marked differences in outcome which appear to exist in subjects who suffer broadly similar head and neck insults. 相似文献
129.
Household survey data on age at first use of alcohol, tobacco, marijuana,and hard drugs can be biased due to sample selection and inaccuraterecall. One potential concern is attrition, whereby individuals who getinvolved with substance use at an early age become increasingly less likelyto be surveyed in successive years. A comparison of data from the NationalHousehold Survey on Drug Abuse (NHSDA) with data from a longitudinal studysuggested that attrition might have caused substantially less bias thandid forward telescoping, the inflating of age at first useover time. The evidence of forward telescoping was particularly pronouncedwith respect to age at first use of alcohol. This paper presents a procedurefor correcting the distribution of age at first use for forward telescoping(but not attrition) by viewing a portion of the NHSDA data collected insuccessive years as constituting a cohort study. Results are presented fromapplying this procedure with NHSDA data collected from 1982 to 1995 forrespondents born 1968–1973. The findings suggest that preventionprograms need to be introduced at an earlier age than would be indicatedby uncorrected retrospective data. Other implications are alsohighlighted. 相似文献
130.