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691.
The degree to which media contributes to body dissatisfaction, life satisfaction and eating disorder symptoms in teenage girls continues to be debated. The current study examines television, social media and peer competition influences on body dissatisfaction, eating disorder symptoms and life satisfaction in a sample of 237 mostly Hispanic girls. 101 of these girls were reassessed in a later 6-month follow-up. Neither television exposure to thin ideal media nor social media predicted negative outcomes either concurrently nor prospectively with the exception of a small concurrent correlation between social media use and life satisfaction. Social media use was found to contribute to later peer competition in prospective analysis, however, suggesting potential indirect but not direct effects on body related outcomes. Peer competition proved to be a moderate strong predictor of negative outcomes both concurrently and prospectively. It is concluded that the negative influences of social comparison are focused on peers rather than television or social media exposure.  相似文献   
692.
This article examines the ways in which International Scientific Collaboration, as observed by the co‐authorship of journal articles written by local scientists and partners located overseas, affects the ability of research teams to produce bibliographic outputs and to contribute to local knowledge. A sample of 672 teams was randomly selected for the analyses. In addition, 20 interviews with experts and team members were administered to discuss models and results. Results show that co‐authoring with partners located overseas increases team output by nearly 40% and by between three and five bibliographic products. It also shows that a team's odds of involving Colombia in its research process are 2.2 times larger for those co‐authoring with a partner located overseas than for those that do not. Theoretical and policy implications are discussed.  相似文献   
693.
This article argues that increased anti-immigrant mobilization (the targeting of ethnic migrants to limit their rights and/or promote their resettlement) in Russia's regions is a consequence of local social movements adopting an anti-immigrant frame as part of their efforts to promote recruitment, acquire resources, and advance their movement's particular cause. Using the cases of Sverdlovsk's Gorod Bez Narkotikov (City Without Drugs) and Krasnodar's Cossack groups, it develops the argument and demonstrates specific ways in which an anti-immigrant frame is taken up by local movements. As a complement to existing studies of anti-immigrant sentiment or far right ideology, these cases highlight the practical politics of mobilizing support for anti-immigration causes in contemporary Russia.  相似文献   
694.
Diverse sources have constructed a common narrative of individual and isolated responses by countries and their leaders to the global coronavirus pandemic, akin to sálvese quien pueda (every man for himself). This article suggests that this is a simplification of the governance of the COVID-19 pandemic in Peru. Peru's governance story is one of domestic public and private action closely interwoven with crucial elements of transnational administration out of sheer necessity. The struggle against the pandemic has generated a domestic and transnational administrative symbiosis, involving authorities at multiple levels in efforts to fill a series of interconnected domestic, regional, and global governance gaps.  相似文献   
695.
The need for agile and proper identification of drugs of abuse has encouraged the scientific community to improve and to develop new methodologies. The drug lysergic acid diethylamide (LSD) is still widely used due to its hallucinogenic effects. The use of voltammetric methods to analyze narcotics has increased in recent years, and the possibility of miniaturizing the electrochemical equipment allows these methods to be applied outside the laboratory; for example, in crime scenes. In addition to portability, the search for affordable and sustainable materials for use in electroanalytical research has grown in recent decades. In this context, employing paper substrate, graphite pencil, and silver paint to construct paper-based electrodes is a great alternative. Here, a paper-based device comprising three electrodes was drawn on 300 g/m2 watercolor paper with 8B pencils, and its efficiency was compared to the efficiency of a commercially available screen-printed carbon electrode. Square wave voltammetry was used for LSD analysis in aqueous medium containing 0.05 mol/L LiClO4. The limits of detection and quantification were 0.38 and 1.27 μmol/L, respectively. Both electrodes exhibited a similar voltammetric response, which was also confirmed during analysis of a seized LSD sample, with recovery of less than 10%. The seized samples were previously analyzed by GCMS technique, employing the full scan spectra against the software spectral library. The electrode selectivity was also tested against 3,4-methylenedioxymethamphetamine (MDMA) and methamphetamine. It was possible to differentiate these compounds from LSD, indicating that the developed paper-based device has potential application in forensic chemistry analyses.  相似文献   
696.
Crop genetic diversity and poverty are linked: first, resource-poor farmers often maintain genetic diversity; and second, crop diversity, when properly valued by the market, has the potential to alleviate poverty. This article examines this supposition by drawing on three case studies of the intersection of the market with poverty and maize diversity in Mexico. These suggest that the bulk market for maize offers little room for maize landraces (local maize varieties known as criollo maize), in that it does not reward qualitative variation in maize grain and instead presents incentives that make planting ‘improved’ maize germplasm the rational economic choice for small-scale farmers. Meanwhile, attempts to add value to maize landraces via market differentiation have had varying success. Although there is potential for differentiated markets to contribute to successful business models and poverty alleviation, these cases exhibit trade-offs between product consistency, investment of labour and resources, and genetic-diversity conservation.  相似文献   
697.
Women's movements made important contributions to ending the period of authoritarian rule in Latin America, but their participation in the reconstruction of democratic politics has been more limited than expected. This paper argues that the enormous influence exerted by technocratic elites in the democratization process in Latin America has represented an obstacle to the improvement of women's status in the region. Gender-biased assumptions and practices have been only partially addressed, in part because the policy-making process is under the control of economists, a professional group with a particularly unfriendly stand towards gendered analysis. It is suggested that reforms within economics may help in the task of making democracy more responsive to the demands of women.  相似文献   
698.
In this paper, we test the effect of three different criminal deterrence theory policy tools: criminal certainty, severity, and celerity of punishment. Whereas most criminal deterrence studies in this field focus on the former two components of deterrence theory, this study also examines the potential deterrent effect of the latter component. Using a time-series design with monthly data, we estimate the effects of an increase in the threat of punishment for traffic offenses resulting from a general increase in fines for traffic offenses, an increase in the probability of getting caught with a blood-alcohol concentration (BAC) level outside the legal limits, and the enactment of an “on-the-spot” fine payment policy in Portugal. We find strong evidence to support a severity effect. An increase in the statutory severity of sentence maxima for traffic violations leads to a decrease in accident and injury rates—approximately an average 0.5 percent reduction in monthly accident and injury rates. Changes in the BAC levels and the mandatory swift payment policy did not produce any convincing deterrence impact.
Cláudia S. CostaEmail:
  相似文献   
699.
Hanging is one of the most frequent methods for suicides among young males. This report presents two cases of suicide by hanging on pylons carrying high-voltage power lines. The male victims suffered electrocution while committing suicide. Electrocution was the cause of death in both cases, however in one case blunt force injuries from hanging contributed to death. In these two cases hanging was the intentional method of suicide and it was followed by electrocution. The cases demonstrate that scene investigation, a detailed autopsy with histology, and amamnestic data are essential in the evaluation of suicides by hanging and that the determination of the cause of death remains a challenge in investigating such cases.  相似文献   
700.
Allele frequency distributions and population data for 12 Y-chromosomal short tandem repeats (STRs) included in the PowerPlex®Y Systems (Promega) were obtained for a sample of 200 healthy unrelated males living in São Paulo State (Southeast of Brazil). A total of 192 haplotypes were identified, of which 184 were unique and 8 were found in 2 individuals. The average gene diversity of the 12 Y-STR was 0.6746 and the haplotype diversity was 0.9996. Pairwise analysis confirmed that our population is more similar with the Italy, North Portugal and Spain, being more distant of the Japan.  相似文献   
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