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A method for the routine profiling of illicit heroin samples received in casework has been developed which depends on simple and straightforward sample pretreatment, followed by gas chromatography on a capillary column using flame-ionization detection. The factors affecting the choice of each aspect of the procedure are discussed, as are the statistical data for sampling and the chromatography. Components of illicit heroin derived from opium and other adulterants have been identified. The significance of data from samples examined in 1986 is discussed. 相似文献
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Jennifer Langhinrichsen Edward Lichtenstein John R. Seeley Hyman Hops Dennis V. Ary Elizabeth Tildesley Judy Andrews 《Journal of youth and adolescence》1990,19(6):623-635
Parental reports of adolescent substance use were compared to the adolescents' self-reports using identical scales. Congruence was defined as exact agreement on whether adolescents were current users, ex-users, or never-users. Both parents were found to be less accurate in predicting their adolescents' alcohol use compared to cigarette or marijuana use. Single mothers were significantly less likely to be congruent than were mothers from two-parent households. Mother and father congruence on all substances was unrelated to the adolescent's sex, race, or after school employment. For both parents, congruence for adolescent marijuana use was significantly related to the age and GPA of the adolescent. Congruence may also reflect important properties of family functioning, as significant relations were found between both adolescent and parent ratings of family cohesion and parent-adolescent congruence on perceptions of marijuana use.This research was supported by Grant DA03706 from the National Institute of Drug Abuse (Hyman Hops, Principal Investigator).Jennifer Langhinrichsen is a doctoral candidate in psychology interested in adolescent and family interactions. The other authors are psychologists or data analysts working on family influences on substance use and mental health. 相似文献
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This article describes assistance that is being provided as part of an institution building project with a view to making a lasting impact on the development of a democratic public service of Ukraine. It explains the nature of the project and the strategies adopted to overcome difficulties. It compares and contrasts approaches adopted by technical assistance projects in assisting administrative reform. It also examines the special nature of the Ukraine project that arises out of the distinctive context and needs of Ukraine. The article continues by examining the role of external assistance in validating the Ukrainian Institute of Public Administration and Local Government's Masters in Public Administration and the contribution made to the development and delivery of the Masters programme. A special feature of the project is the series of one-month internships when IPALG students visit London. The internship programme allows students to identify aspects of UK experience relevant to changes that Ukraine wishes to make in its administrative culture. As part of this programme, students are placed in government organizations and NGOs. The placements are complemented by a series of change management seminars that enable students to evaluate options for change, to assess their own role in the change process and recognize the key stages in the change process. The project team has undertaken a full evaluation of the first presentation of the programme and the article presents the findings. 相似文献
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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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A path-analytic study was undertaken to investigate the proposed relationship between physical attractiveness, need for intimacy, self-disclosure, thought about one's dating partner, and reported romantic love. Extrapolations from theories by Murstein (1971) and I. Reiss (1960), and conclusions from other empirical work, provided the background for the assessment of the relationship between the four proposed predictive factors and the development of romantic affect. During the winter of 1977-78 656 college students responded to a survey assessing each of the four predictors and romantic love. Path structures were initially estimated for male and female subsamples. Since few significant sex differences were noted, coefficients were compared for groups of students involved in dating relationships of varying durations. All four predictors were significantly associated with the subjects' self-reported romantic affect toward their dating partner. In all analyses, thinking about one's partner was found to be the most potent predictor. The data suggest the earlier work by Murstein and Reiss offer both testable and productive theoretical foundations for the study of romantic involvement. However, in future work it would be beneficial to (a) search for more numerous and powerful antecedents to romantic love; (b) delineate the specific role of cognitive processes in influencing romantic attachment; (c) compare relationships on criteria other than months of involvement; and (d) seek to examine love from the perspectives of both individuals involved in the dyadic relationship.Received her Ph.D. from the Pennsylvania State UniversityReceived his Ph.D. from The Pennsylvania State University. 相似文献
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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