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61.
Laser desorption mass spectrometry (LDMS) may be used for the detection and identification of dyes found in inks. Naturally-aged and artificially-aged blue and black ballpoint pen inks containing the cationic dye methyl violet were analyzed on paper. The average molecular weight of the dye sample was calculated from LD mass spectral data and plotted versus time. The resulting aging curves demonstrate that, as dye degradation increases, the average molecular weight of the dye decreases. Typical variables involved in ink aging, such as the type of paper and ink formulation, were investigated. Results show that these variables influence the rate of dye degradation. Furthermore, UV accelerated aging has been developed and tested as an alternative to thermal approaches.  相似文献   
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To answer the question whether a negative result of gas chromatographic blood analysis for components of chemical mace proves that no or at most only slight tear gas exposure can have occurred, animal experiments were carried out. In the blood of 10 guinea pigs, which were exposed to the contents of chemical mace for 1--6 h, the solvants 1,1,2-trichloro-1,2,2-trifluorethane (freon 113) and 1,1,1-trichloroethane could easily be detected--even 23 h after the end of exposure or after a storage of the blood samples for 18 weeks--whereas the lacrimator chloracetophenone (CN) could not be found at all. In vitro experiments showed that CN relatively quickly reacts with components of blood. Therefore, blood samples should be analyzed for CN after withdrawal as soon as possible. In case of inhalation of the contents of chemical mace, i.e., after the comparatively mildest form of CN application, most probably no traces of the lacrimator at all can pass into the blood due to the quick reaction of CN with proteins of the respiratory surface of the lung.  相似文献   
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Reviews the need for and development of expanded school mental health (ESMH) programs, which provide a continuum of mental health promotion and intervention through school–community partnerships. Since ESMH is a relatively new, but increasingly prominent field, countless issues are being addressed in practice and research and in efforts to bridge practice and research. We review particular content and context dimensions of ESMH in need of development including quality assessment and improvement, empirically supported practice, improving assessment and outcome evaluation, involving educators in the work, understanding school environments, and tailoring programs through qualitative research. Summaries of articles that amplify these themes are provided.  相似文献   
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In this paper symbolic inclusion/exclusion processes in sport with respect to gender and ethnicity among adolescents (n = 1025) are analyzed from a social-critical perspective. It was found that sport participation preferences of young people are still influenced by dominant normative gendered and racial/ethnic images. Sport can serve not only as an agent of integration among youth, but is also used to differentiate and discriminate. On one hand sport participation is less predictable with respect to gender, due for example to interactions with ethnicity. Although ethnic minority girls participate the least in sport, ‘black,’ traditional ‘masculine‘ sports such as soccer and fighting/self-defense are valued relative highly. On the other hand, the data show that especially the male adolescents symbolically exclude girls from ‘masculine’ sports such as soccer; in addition for both ethnic minority and majority boys the fear of being labelled as a ‘sissy’ works as a strong mechanism of self-exclusion from participation in traditional ‘feminine’ sports. However, stereotypical normative images are not only confirmed through sport (participation), but also continually challenged.Researcher/lecturer, Tilburg University. Research interest in inclusionary and exclusionary mechanisms in sport, especially with respect to gender, ethnicity and sexuality.Senior researcher, Utrecht University. Major research interest in gender, ethnicity and leadership positions in sport.  相似文献   
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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   
69.
In the present longitudinal 3-wave study of 1274 adolescents and young adults, aged 12–24 at the 1st wave, it is examined whether youngsters from intact versus postdivorce families show long-term differences in internalizing and externalizing problems. Furthermore, possible differences in the development of this problem behavior between offspring from intact and postdivorce families are examined, i.e., possible differences in growth curves of internalizing and externalizing problems are investigated. Longitudinal multilevel analyses reveal long-term differences in internalizing and externalizing problems according to family structure. Adolescents and young adults growing up in postdivorce families display more internalizing and externalizing problem behavior than youngsters of intact families. The development of these 2 types of problem behavior does not differ by gender or family structure. That is, the shape of the growth curves of internalizing and externalizing problem behavior is similar for boys and girls and also for youngsters from intact and postdivorce families. Inge VanderValk is a Postdoc Researcher at the Department of Child and Adolescent Studies, Utrecht University, the Netherlands. She received her Ph.D. in 2004 from Utrecht University. Her major research interests include associations between adolescent adjustment and parental marital quality and parental divorce. Ed Spruijt is an Associate Professor at the University of Utrecht. He received his Ph.D. in 1983 from Utrecht University. His major research interests are the consequences of parental divorce and visitation arrangements on children. Martijn de Goede is an associate Professor at Utrecht University, Department of Methodology and Statistics. He received his Ph.D. in 1988 from Utrecht University. His major research interests are occupational and relational life courses of youngsters. Cora Maas is an Assistent Professor at Utrecht University, Department of Methodology and Statistics. She received her PH.D. in 1992 in Utrecht from Utrecht University. Her major interests are: multilevel analysis (theory and applications). Wim Meeus is full Professor of Adolescent Development at Utrecht University. He received his Ph.D. in 1984 from Utrecht University. His major research interests are personality, identity, and relationships in adolescence.  相似文献   
70.
Due to conceptualizations of autonomy as detachment and independence, research on the parenting–autonomy relationship in adolescence has yielded inconsistent results. In the present study, self-determination is proposed as an alternative way of tapping into the construct of autonomy. An integrated model of the relationships between perceived parenting and teaching styles, self-determination in 3 life-domains (school, social competence, and job-seeking behaviors), and specific adolescent outcomes, was investigated and confirmed. In 2 samples of mid-adolescents (N = 328 and N = 285), autonomy-supportive parenting was significantly related to self-determination in all life-domains. Autonomy-supportive teaching added significantly to the prediction of self-determination in the domains of school and job-seeking behaviors. Self-determination, in turn, was positively and specifically associated with measures of adjustment in the specific life-domains under investigation. Finally, in both studies, indications were found that self-determination acts as an intervening variable in the relation between the perceived interpersonal environment and adolescent adjustment. Doctoral student at the Center for Developmental Psychology at the Katholieke Universiteit Leuven, Belgium. His major research interests are parenting, psychological control, and identity development. Postdoctoral researcher at the Center for Motivation Psychology at the Katholieke Universiteit Leuven, Belgium. His major research interests are self-determination theory, motivation, and parenting.  相似文献   
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