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241.
The authors investigated the dimensions and mechanisms of belonging relevant to motivation and achievement among high school students representing 4 ethnic groups. Using survey data from 9th to 12th grade students (N = 5,494) attending 7 ethnically-diverse high schools, structural equation modeling was employed to explore, independently for each ethnic group, the relationships between students’ perceptions of their belonging (encompassing relationships with teachers and peers, extracurricular involvement, and perceived ethnic-based discrimination), motivation (efficacy beliefs and valuing school activities), and academic success. All 4 measures of belonging were significant for European-American and Latino students. However, friendship nominations were not significant for all groups, suggesting potential variability in perspectives across ethnic groups. The strength of the structural model postulating belonging as a mediator, including statistically significant indirect paths, supported the hypothesis that the belonging construct accounted for much of the relationship between student motivation and success across groups.Beverly Faircloth is a doctoral candidate of the University of North Carolina at Chapel Hill. Her research interests include the developmental and motivational processes that support adolescent school engagement in ethnically diverse settings.Jill Hamm is an Assistant Professor at the University of North Carolina at Chapel Hill. She received her Ph.D. from the University of Wisconsin-Madison in 1996. Her research interests are adolescents’ peer relations in ethnically diverse schools and classrooms. 相似文献
242.
This ecological study examined the association between seven socioeconomic indicators (GDP, unemployment rate, female labor force participation rate, alcohol expenditure, marriage rate, percentage of births outside of marriage, and indictable crime rate) and total, male, and female rates of suicide and suicide plus undetermined death in Ireland during the period 1968-2000. Analysis of the data expressed as absolute values showed highly significant associations between the socioeconomic indicators and the total, male, and female suicide rates. However, these associations were explained by the strongly trended data. The trended nature of the data was removed by using year-to-year differences. Analysis of the first-differenced data showed that none of the socioeconomic indicators was associated with the total, male, or female suicide rates with the exception of indictable crime, which had a significant independent effect on the female suicide rate (coefficient = 2.0, p < .01) but not on suicide plus undetermined death. This study highlights the need to use econometric methods in time-trend analyses, the lack of age-sex specific exposure data in this area, and the challenge of understanding trends in suicide in their socioeconomic context. 相似文献
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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
245.
Fartushnyĭ AF Sukhin AP Gerasimenko AI Shevchenko VV Sborshchik EA 《Sudebno-meditsinskaia ekspertiza》2005,48(2):38-41
A method was suggested for identifying reladorm and donormil in pharmaceutical drugs and biological objects. The above substances are isolated by 96% ethanol or by mixture of chloroform and isopropanol. 7 color reactions, 3 microcrystalloscopic reactions and chromatography in thin sorbent layer are suggested for identification. 相似文献
246.
Posttraumatic alterations in the cervical spine ligaments were studied clinically and psychologically in the victims with mechanical injuries of the musculoligamentous system of the cervical spine. A clinical course of the traumatic process and biomechanical musculoligamentous alterations, development and severity of mental disorders were established. These characteristics should be taken into consideration in forensic medical evaluation of health deterioration. 相似文献
247.
The technique is proposed allowing quantitation of brain edema and typing of liquor distribution in different parts of brain tissue. In combination with other assays this test can determine a variant of tanatogenesis, detect cause of death and duration of the terminal period. The method application is illustrated by the study of brain hydration in mechanical strangulation asphyxia. It is shown that this death is associated with hypohydration of cerebral structures, especially pronounced in the cortical compartments. 相似文献
248.
A complex investigation of catalase activity in erythrocytes was conducted basing on the results of computer quantitative morphometry of histochemical examination of blood samples from persons with mild craniocerebral trauma. It was found that erythrocytic catalase activity correlates with severity of brain trauma. A novel technique of objective histochemical diagnosis of trauma is described. It provides objective grounds for expert conclusions. Differential features of erythrocytic shape were defined in a small series of micropreparations vs the rest blood samples. 相似文献
249.
250.