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81.
The purpose of this study was to test hypotheses regarding (1) relations among negative affect and hormones of gonadal and adrenal origin in young adolescents, at three times of measurement, over a one-year period; and (2) stability of negative affect. The sample consisted of 10- to 14-year-old boys (N=56) and 9- to 14-year-old girls (N=52). The adolescents were assessed three times at 6-month intervals over one year. Serum levels of gonadotropins, gonadal steroids, adrenal androgens, and cortisol were assessed, as well as stage of pubertal development (Tanner criteria). The negative affect assessments consisted of self-report questionnaire and interview measures of anxiety and depressive affect, as well as mother reports of internalizing behavior problems. In the concurrent (cross-sectional) analyses, boys reporting higher levels of negative affect tended to be those at higher genital stage or older age, with lower testosterone and cortisol levels and lower dehydroepian-drosterone sulphate levels. In the longitudinal analyses, negative affect, and to a lesser extent hormone levels at the first time of measurement predicted negative affect 12 months later. The findings suggest that puberty-related hormone levels should be considered along with psychological characteristics in examining the processes involved in the development of negative affect during the pubertal years.Received Ph.D. from The Pennsylvania State University. Research interests include hormone-behavior interactions and emotional development.Received Ph.D. from The Pennsylvania State University. Research interests include neuroendocrinology and adolescent depression.Recieved M.D. from Athens University. Research interests include hypothalamic releasing factors and stress.  相似文献   
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Validation of a 16-locus fluorescent multiplex system   总被引:24,自引:0,他引:24  
STR multiplexes have been indispensable for the efficient genotyping of forensic samples. The PowerPlex 16 System contains the coreCODIS loci, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D21S11, CSF1PO, FGA, THOI, TPOX, vWA, the sex determinant locus, amelogenin, and two pentanucleotide STR loci, Penta D and Penta E. This multiplex satisfies the locus requirements for most national databases and is the most efficient currently available system due to its single PCR amplification. To provide the groundwork for judicial acceptance, including the publication of primer sequences, and to evaluate laboratory-to-laboratory variation, a developmental validation for casework on this commercially available system was performed in 24 laboratories and produced the following conclusions. Amplification was reliable on a variety of thermal cyclers and product could be analyzed on either an ABI PRISM 310 Genetic Analyzer or an ABI PRISM 377 DNA Sequencer. Genotyping using single source samples was consistent between 0.25 and 2 ng of input DNA template with a few laboratories obtaining complete genotypes at 0.0625 ng. However, heterozygote allele imbalance (<60% peak height balance) caused by stochastic effects was observed at a rate of 13% with 0.125 ng DNA and 22% at 0.0625 ng DNA. Mixture analyses were done using a total of 1 ng of DNA template. Most alleles were detected in mixtures of 4 to 1 and some minor alleles were detected in mixtures of 19 to 1. Optimum amplification cycle number was dependent on the sensitivity of the detection instrument used and could also be adjusted to accommodate larger amounts of DNA on solid supports such as FTA paper. Reaction conditions including volume, annealing temperature, and concentrations of primer, AmpliTaq Gold, and magnesium were shown to be optimal yet robust enough to withstand moderate variations without affecting genotype analysis. Environmental, matrix and standard source analyses revealed an ability to obtain complete genotypes in all sample types except those exposed to 80 degrees C for 12-48 days. Finally, comparison of genotype results from the PowerPlex 16 System with other commercially available systems on non-probative reference and forensic samples showed consistent results.  相似文献   
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Abstract: Efforts to design merit‐based appointment systems for the boards of government agencies, boards and commissions (abcs) have gained greater priority over the past decade in order to enhance public confidence in the integrity of the political process, improve the governance of organizations operating at arm's length from ministers, and reduce the risks to the public interest and public purse that come with incompetent boards. The Nova Scotia reform experience in this regard is instructive because this province's appointment regime not only encompasses a legislative committee veto over ministerial appointments, a power unique to this province in the Canadian and comparative Westminster systems, but also uniquely sets the merit standard as relative‐merit, that is, the appointment of the most qualified of all applicants, and not merely a qualified candidate. This article reviews this provincial experience and concludes that a merit‐based appointment system that pursues relative merit can be created but only by restricting the authority of ministers to a veto over the appointment of candidates nominated by the abcs themselves. Sommaire: Ces dix demières années, les efforts déployés pour concevoir des systemes de nomination au mérite pour les conseils d'administration d'organismes, des régies et des commissions du gouvernement ont obtenu une priorité beaucoup plus grande, et cela, afin de rehausser la confiance du public envers I'intégrite du processus politique, d'ameliorer la gouvernance d'organismes fonctionnant sans contrôle ministériel direct et de réduire les risques que représentent les conseils incompétents pour le bien et les deniers publics. L'expérience de la réforme entreprise en NouvelleÉcosse est à cet égard instructive pour les partisans de la réforme. Le régime de nomination de cette province comporte non seulement un droit de veto de la part d'un comité législatif sur les nominations ministéielles, pouvoir unique à cette province dans le systéme canadien et le systéme comparatif de Westminster, mais il établit également la norme de mérite comme un mérite relatif, c'est‐à‐dire la nomination de la personne la mieux qualifiée parmi tous les candidats et non simplement la nomination d'une personne qualifiée. Le présent article examine I'expérience de cette province et conclut qu'un système de nomination au mérite visant le mérite relatif peut être mis en place, mais seulernent à condition de limiter le pouvoir des ministres à opposer leur veto à la nomination de candidats par les organismes, régies et commissions gouvernementaux.  相似文献   
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Parker  Glenn R.  Powers  Stephen C. 《Public Choice》2002,110(1-2):173-191
Despite the hypothesized propensity for shirking to marklegislative institutions, the evidence is rather equivocal;moreover, most of the research has focused exclusively onlegislator voting, thereby constraining whatevergeneralizations might emerge. The purpose of this paper is tocontribute to the debate over the question of politicalshirking by extending the range of phenomena examined toinclude congressional foreign travel. Our analysis providesevidence that opportunism is a problem in Congress. We findthat last-period problems have arisen in the area of foreigntravel, and that increased scrutiny to the problem on the partof Congress only shifted consumption patterns, i.e.,legislators began taking foreign junkets near, but not at theend of, their legislative careers. Not all foreign travelshould be construed as worthless junketing since there isstrong evidence that some foreign travel is related tomembers' responsibilities on congressional committees.  相似文献   
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Grassroots environmental activism among Latin America's poor has altered the debate over environmental policy, social welfare, and citizenship. Yet the question remains whether this social mobilization of the poor is part of a larger trend toward broader environmental concerns and democratic political participation, or a shortlived movement susceptible to the same pressures that have dissolved community mobilization in the past. This article compares Brazil with other Latin American and European countries in surveys of environmental awareness, concerns, and reported behavior. It finds that Brazilians residing in the urban periphery link their own local environmental concerns to more global considerations, and that concern for and activism on environmental issues is positively related to wider community involvement.  相似文献   
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The authors report a fatal case of a Persian leopard (Panthera pardus) attack in an animal sanctuary in Oklahoma. The victim was a 53-year-old Costa Rican woman who was attempting to feed the animal when she was attacked and killed. Autopsy, radiography, fingerprint analysis, microbiologic cultures, and dental impressions were used to evaluate the case. These simple techniques can be applied to similar cases involving wild and domestic animal attacks.  相似文献   
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