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131.
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
132.
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
133.
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
134.
Ego identity status and decision styles 总被引:1,自引:0,他引:1
It was hypothesized that the decision processes used in coping with the identity crisis would be related to more general decision styles in that identity achievers and moratoriums would tend to be reflective in their conceptual tempo while foreclosures would typically be impulsive. No prediction was made about identity diffusions. Ninety-two male college students were given an identity status interview and the Matching Familiar Figures Test. The results were consistent with the hypotheses, and in addition it was found that identity diffusions were generally impulsive. Since conceptual tempo has been found to be well established in childhood, the results of this study have implications for the early prediction of adult identity status.Received Ph.D. from SUNY/Buffalo. Recent research has been mainly concerned with the development of ego identity and correlates of the different identity statuses.Received Ph.D. from SUNY/Buffalo. Recent research has been mainly concerned with the development of ego identity and correlates of the different identity statuses. 相似文献
135.
Alan Roberts 《Democracy & Nature》2000,6(3):447-461
When a new property is required to characterise an altered system, it is said to be 'emergent'. The fundamental importance of emergence for social activists is stressed. It is proposed that we deepen our understanding of it by examining well-understood processes to see exactly how new properties emerge in them. Reasons are given for hoping that this approach can be more fruitful now than in past eras. To illustrate the method, a simple case is examined which brings out inter alia the role of the environment and the precise way that a continuous process underlies the abrupt emergence. The results appear encouraging enough to stimulate further studies along these lines, and it is suggested where suitable cases can be found. 相似文献
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138.
Alan W. Black 《Australian Journal of Public Administration》1974,33(4):332-345
The outcomes of various modes of administration may be summarized as follows:
- 1 Under both ministerial and departmental control, the prior experience and predispositions of the Minister were critical factors affecting the colleges. Under departmental control, the background and attitudes of senior officers within the department were also important. Various instances of this were cited.
- 2 There tended to be proportionately fewer dismissals of principals or resignations in protest by them under departmental control than when colleges were controlled by Ministers of the Crown or governing councils. Several reasons for this trend were suggested.
- 3 Under all systems of control the colleges were subject from time to time to direct or indirect political pressure. For example, there were instances in which parents invoked or attempted to invoke political pressure to save their sons from expulsion from a college. Such pressures played a part in the dismissal or resignation of several principals.
- 4 Another factor which led to the resignation of two principals who were directly responsible to a Minister was the belief that their jurisdiction had been transgressed by another senior public servant.
- 5 Under departmental control a principal was likely to be caught up in intradepartmental politics. The fortunes of the college depended somewhat upon his success in this arena.
- 6 In determining the policies and practices to be adopted on the college farm, a principal generally had greater freedom under Education Department control than under Agriculture Department control. On the other hand, teaching practices were generally subject to closer departmental supervision in the former case than in the latter.
- 7 One problem with any system of control is that of maintaining a balance between continuity in policy on the one hand and sensitivity to demands for change on the other. In general, control over the colleges by government departments or governing councils tended to be conservative in emphasis, to stress continuity. By contrast, where control was directly exercised by Ministers of the Crown and where there were relatively frequent changes in incumbency of the relevant portfolio, continuity in policy was less assured.
- 8 The life of advisory committees was typically marked by early enthusiasms and influence in dealing with urgent matters of policy. After these matters had been dealt with there was generally a decline in activity and influence, growing disillusion among members, and eventually reconstitution or replacement of the committee.
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140.
Johnson RD Lewis RJ Canfield DV Dubowski KM Blank CL 《Journal of forensic sciences》2005,50(3):670-675
Specimens from fatal aviation accident victims are submitted to the FAA Civil Aerospace Medical Institute for toxicological analysis. During toxicological evaluations, ethanol analysis is performed on all cases. Care must be taken when interpreting a positive ethanol result due to the potential for postmortem ethanol formation. Several indicators of postmortem ethanol formation exist; however, none are completely reliable. The consumption of ethanol has been shown to alter the concentration of two major serotonin metabolites, 5-hydroxytryptophol (5-HTOL) and 5-hydroxyindole-3-acetic acid (5-HIAA). While the 5-HTOL/5-HIAA ratio is normally very low, previous studies using living subjects have demonstrated that the urinary 5-HTOL/5-HIAA ratio is significantly elevated for 11-19 h after acute ethanol ingestion. Recently, our laboratory developed and validated an analytical method for the simultaneous determination of both 5-HTOL and 5-HIAA in forensic urine samples using a simple liquid/liquid extraction and LC/MS/MS and LC/MS/MS/MS. In this previous work a 15 pmol/nmol serotonin metabolite ratio cutoff was established in postmortem urine, below which it could be conclusively determined that no recent antemortem ethanol consumption had occurred. In the current study this newly validated analytical method was applied to five ethanol-positive aviation fatalities where the origin of the ethanol present could not previously be conclusively determined. In four of the five cases examined the detected ethanol was demonstrated to be present due to postmortem microbial formation, and not consumption, even though some indication of ethanol consumption may have been present. 相似文献