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991.
Girls’ early pubertal timing has been linked in many studies to behavioral problems such as delinquency and substance use. The theoretical explanations for these links have often involved the girls’ peer relationships, but contexts have also been considered important in some explanations. By integrating two theoretical models, the peer-socialization and the contextual-amplification hypotheses, we propose a contextual framework for explaining the link between early pubertal timing and external problem behavior in girls. We hypothesize that early developing girls engage in unhealthy, dangerous, and risky behavior under contextual conditions that promote access to older friends and opposite-sex relationships. Under other conditions it is less likely. We tested this integrated hypothesis in two studies conducted in Sweden. The first was a cross-sectional study with information about school and free-time friends in a community sample (N = 284). Early pubertal timing was linked to having older, more normbreaking friends outside of school, but not in school, thus suggesting that the school context interferes early-developing girls’ selection of older peers. The second study involved both a longitudinal (N = 434) and a cross-sectional sample of girls (N = 634), where we examined a leisure setting that is known to attract delinquent youth. Results showed that early pubertal timing was most strongly linked to delinquency for girls who spent time in this context and were heavily involved with boys and peers. In sum, results from both studies supported our predictions that certain contexts would amplify the peer-socialization effect. Overall, we conclude that the integrated peer-socialization/contextual-amplification model satisfactorily explains the link between pubertal timing and external problem behavior.  相似文献   
992.
Programmatic research has made important advances during the last decade in understanding how cognitive and psychological variables affect Miranda comprehension and reasoning. However, the effects of situational stressors are largely overlooked in determining the validity of Miranda waivers. As the first systematic investigation, this study uses a 2 × 2 × 2 factorial design on 123 undergraduate participants to examine the effects of being apprehended via a mock crime (i.e., stealing a watch from a Plexiglas case) paradigm on Miranda comprehension and reasoning. Besides the mock-crime condition, the mode of advisement (oral or written) and the length of the warning (124 vs. 228 words) were also investigated. When compared to controls, the mock-crime scenario produced moderate to large effects (ds from .58 to .75) on both Miranda recall and subsequent reasoning. In addition, oral advisements resulted in non-significant trend for decrements in Miranda recall. No main effects were observed for length and no significant interactions were found. Interestingly, specific components (e.g., right to counsel and free legal services) were generally more affected than the more familiar first two components (i.e., right to silence and evidence against you). Within the crime-scenario condition, participants with substantially increased state anxiety predictably performed more poorly than those participants whose state anxiety remained relatively stable. Directions for future research and the implications of these findings on our understanding of Miranda abilities are discussed.  相似文献   
993.
A firm can improve its innovation either by its internal research and development (R&D) efforts or by forming external collaborative R&D alliances. While previous studies on R&D collaboration and knowledge diffusion mainly focus on various external sources of R&D collaboration, little effort has been made to investigate the joint impact of competitive and non-competitive R&D collaborations on firm innovation simultaneously. By examining the data of 165 Taiwanese firms in the information and communication technology industry, we find that: (1) non-competitive R&D collaborations with universities have a positive direct impact on firm’s innovation performance; and (2) both non-competitive and competitive R&D collaborations have a positively moderating effect on the relationship between a firm’s internal R&D efforts and firm innovation and the positive moderating effect is higher for non-competitive R&D collaborations than that of competitive R&D collaborations. These findings suggest that R&D collaborations, either non-competitive or competitive, exhibit the nature of a win–win situation. We also derive implications for firms’ selection of R&D alliance partners and government policies.  相似文献   
994.
OBJECTIVE: The aim of this study was to investigate the association between adverse physical disorders and violent/non-violent criminal behaviour. DESIGN: The study material consisted of the large, prospectively followed, unselected and genetically homogeneous Northern Finland 1966 Birth Cohort, the Finnish Hospital Discharge Registers and the National Crime Register (n=10934). MAIN RESULTS: The results of the logistic regression analyses showed that male offenders had statistically significantly more injuries (adj. OR=1.81, 95% CI=1.51-2.17), when compared with males without a criminal history. Violent male offenders exhibited greater morbidity to the diseases of the respiratory system (adj. OR=1.64, 95% CI=1.03-2.60) when compared with non-violent criminals. Female offenders suffered more commonly from poisonings (adj. OR=3.84, 95% CI=1.69-8.72), injuries (adj. OR=2.79, 95% CI=1.67-4.66), infections (adj. OR=1.87, 95% CI=1.16-2.99) and indefinite symptoms (adj. OR=2.02, 95% CI=1.20-3.40) than non-offending females. CONCLUSIONS: At epidemiological level, criminal behaviour seems to be associated especially with an increased risk of injuries for both sexes. The observed increase of the diseases of the respiratory system among violent but not among non-violent males calls for further investigations.  相似文献   
995.
In this article, two unexplored trends in European electoral politics are highlighted. Using newly collected data the article tracks the politicisation of corruption in electoral campaigns from 1981 to 2011, an electoral strategy that has been increasing over time in most European countries. It then empirically tests two aspects of this campaign strategy. First, what are the factors that are systematically associated with a party’s decision to politicise corruption? Second, what are the electoral effects in terms of relative vote share for parties that politicise corruption? Using an original data-set that employs multi-level data (parties nested in countries) the results demonstrate first that politicisation of corruption occurs systematically more often among established parties from the main opposition, new parties and parties on the political right, and occurs as a function of country-level corruption, district magnitude and public party financing. Second, it is found that the main opposition and new parties that use such a campaign strategy make significant electoral gains relative to the previous election compared to parties that do not politicise corruption. Yet gains are offset in low-corruption countries. The findings demonstrate salient implications for research on party systems, corruption studies and democratic legitimacy, among other areas of investigation.  相似文献   
996.
997.
The article discusses Russian implementation of the Ramsar Convention, the World Heritage Convention, CITES and the Convention on Biological Diversity. The country's international obligations are part of Russian law, but little has been done by Russian authorities to implement the agreements on the ground. Compliance with the international agreements is the result of Russian protection measures that exist independently of the conventions. Environmental concerns have been given reduced priority since the early 1990s. An independent environmental protection agency no longer exists, and the number of inspectors has been drastically reduced. Implementation activities are undertaken primarily by international NGOs, and partly by regional authorities.  相似文献   
998.
Political involvement varies markedly across people. Traditional explanations for this variation tend to rely on demographic variables and self-reported, overtly political concepts. In this article, we expand the range of possible explanatory variables by hypothesizing that a correlation exists between political involvement and physiological predispositions. We measure physiology by computing the degree to which electrodermal activity changes on average when a participant sequentially views a full range of differentially valenced stimuli. Our findings indicate that individuals with higher electrodermal responsiveness are also more likely to participate actively in politics. This relationship holds even after the effects of traditional demographic variables are taken into account, suggesting that physiological responsiveness independently contributes to a fuller understanding of the underlying sources of variation in political involvement.  相似文献   
999.
Using the Purkinje cells of the cerebellum from 42 rapidly and 28 slowly dying patients, we tried to find a correlation between the premortal hypoxie in brain and the result of HBFP staining. We found four different stages of staining and discuss here the causes of staining and false results.  相似文献   
1000.
In head-on collisions, loose items in the rear of the car, such as luggage or unrestrained back seat passengers can cause substantial loading on the back of the front seats. The purpose of this paper is to study if such loading increases the injury severity for the front seat occupants. Data were collected from all fatal automobile accidents for a period of 1 year in Sweden. Information was collected about the survivors as well as the decreased. Head-on collisions were selected, and the injuries of the front seat occupants were scored according to the Abbreviated Injury Scale (AIS) and the Injury Severity Score (ISS). In evaluating the injury severity, the collision energy was taken into account. The results indicate that belted front seat passengers sustain a higher injury risk with an unrestrained passenger in the back seat. These results are valid for collision speeds below 45 km/h.  相似文献   
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