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211.
Romão W Vaz BG Lalli PM Bueno MI Correa DN Telles VL de Castro EV Eberlin MN 《Journal of forensic sciences》2012,57(2):539-543
Using desorption/ionization techniques such as easy ambient sonic-spray ionization mass spectrometry (EASI-MS), it is possible to analyze documents of Brazilian vehicles for authenticity, providing a chemical profile directly from the surface of each document. A method for the detection of counterfeit documents is described, and the falsification procedure is elucidated. Forty authentic and counterfeit documents were analyzed by both positive and negative ion modes, EASI(±)-MS. EASI(+)-MS results identified the presence of (bis(2-ethylhexyl)phthalate plasticizer and of dihexadecyldimethylammonium biocide in both types of documents. For EASI(-)-MS results, the 4-octyloxybenzoic acid additive ([M + H](+): m/z 249) is present only in counterfeit documents. It was also found that counterfeit vehicle documents are produced via Laserjet printers. Desorption/ionization techniques, such as EASI-MS, offer therefore, an intelligent way to characterize the counterfeiting method. 相似文献
212.
Brion M Allegue C Santori M Gil R Blanco-Verea A Haas C Bartsch C Poster S Madea B Campuzano O Brugada R Carracedo A 《Forensic science international》2012,219(1-3):278-281
In developed countries, sudden infant death syndrome (SIDS) represents the most prevalent cause of death in children between 1 month and 1 year of age. SIDS is a diagnosis of exclusion, a negative autopsy which requires the absence of structural organ disease. Although investigators have confirmed that a significant percentage of SIDS cases are actually channelopathies, no data have been made available as to whether other sudden cardiac death-associated diseases, such as hypertrophic cardiomyopathy (HCM), could be responsible for some cases of SIDS. The presence of a genetic mutation in the sarcomeric protein usually affects the force of contraction of the myocyte, whose weakness is compensated with progressive hypertrophy and disarray. However, it is unclear whether in the most incipient forms, that is, first years of life, the lack of these phenotypes still confers a risk of arrhythmogenesis. The main goal of the present study is to wonder whether genetic defects in the sarcomeric proteins, previously associated with HCM, could be responsible for SIDS. We have analysed 286 SIDS cases for the most common genes implicated in HCM in adults. A total of 680 mutations localised in 16 genes were analysed by semi-automated matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDITOF-MS) using the Sequenom MassARRAY(?) System. Ten subjects with completely normal hearts showed mutated alleles at nine of the genetic variants analysed, and one additional novel mutation was detected by conventional sequencing. Therefore, a genetic mutation associated with HCM may cause sudden cardiac death in the absence of an identifiable phenotype. 相似文献
213.
Using co-citation analysis, the present study attempts to rationalize and organize the combined alliance and innovation literature in order to determine its intellectual structure (i.e. its shared attributes such as models, theories, methods, findings, and implications), as well as to gain a deeper understanding of the most important research trends. More specifically, our goals are: (1) to delineate the intellectual structure of research on alliance and innovation, as represented in the academic literature; (2) to determine the subfields that constitute the intellectual structure and the relationships, if any, between these subfields; (3) to identify contributions that play a pivotal role in bridging two or more conceptual domains of research; and finally, (4) to map the intellectual structure in a two-dimensional space in order to visualize spatial distances between intellectual themes. Implications for future studies are then drawn. 相似文献
214.
215.
Objectives
The aim of this paper is to respond to the commentary of Peter K. Smith, Christina Salmivalli, and Helen Cowie (Journal of Experimental Criminology, 2012), who raise concerns regarding some of the findings of our systematic review and meta-analyses on the effectiveness of bullying prevention programs. They target three findings in particular: (1) the significant association of ??Work with Peers?? with greater victimization; (2) the significant association of ??Disciplinary Methods?? with less bullying perpetration and victimization; and (3) the age variations in effectiveness, suggesting larger effect sizes for older age students.Methods
We provide explicit information and further detailed analyses on the relationship between these features and effect sizes, including heterogeneity tests and results from weighted regression analyses. For one element in particular (work with peers), we present further research findings from evaluations conducted by Smith, Salmivalli, and Cowie (and also findings from other independent researchers) which support our previous findings. New within-program analyses to examine variations in effect sizes with the age of the students are also presented.Results
Evaluations conducted by Smith, Salmivalli and Cowie (and by other independent researchers) indicate the same research conclusions: although peer support schemes appear effective based on attitudinal surveys, these schemes are not related to actual levels of bullying or victimization and, in fact, are quite often related to an increase in bullying and victimization. Our definition of ??disciplinary methods?? did not include the zero-tolerance approach or any type of harsh discipline as suggested in the commentary. In all relevant cases, ??disciplinary methods?? included sanctions within a warm and loving framework, following the Olweus bullying prevention guidelines. While most programs that utilized firm disciplinary methods were inspired by Olweus, the relationship between disciplinary methods and less victimization was not driven by the Olweus program (which was not related to the victimization effect size). Larger effect sizes (i.e. reductions in bullying and victimization) for programs implemented with older students is a robust result also found in a more recent systematic review regarding the effects of anti-bullying programs on bystander intervention. In within-program analyses, most results suggested that effect sizes were greater for younger students, but these results were driven by the less controlled evaluations. The most controlled evaluation (randomized experiment) provided the opposite result.Conclusions
More research is clearly needed on the effectiveness of bullying prevention programs with students of different ages, and we also recommend randomized experiments to assess the importance of different intervention components. 相似文献216.
217.
Maria Sofia Corciulo 《议会、议员及代表》2013,33(1):55-64
SUMMARYThe two pioneers in introducing direct democratic instruments in modern Europe were France and Switzerland from the turn of the eighteenth and nineteenth centuries. After the First World War different kinds of referendums and popular initiatives were also adopted by other countries. The Weimar Republic and the Republic of Estonia had the most noteworthy practice with direct democracy. This article examines the regulation and practice of popular rights in these two countries focusing on their function in the political system and on the relation of direct democracy and representative state organs. It seeks an answer to the question of how Parliaments were challenged by popular initiatives and how representative power reacted to direct democratic events. 相似文献
218.
This note summarises our replication study ‘Housing, Health, and Happiness’, henceforth HHH2009, which constitutes an important paper in the literature of housing and slum upgrading. The original authors conduct a quasi-experimental impact evaluation of ‘Piso Firme’, an intervention that replaced in-house dirt floors with cement in Mexico. We conduct a Pure Replication (PR), a Measurement and Estimation Analysis (MEA), and a Theory of Change Analysis (TCA). In our PR, we did not find any major discrepancy with the original study. In the MEA, we generally find the results to be strongly robust to different types of alternative analysis. Finally, in TCA we explore a dimension that was not reported on the published version of the study and found that households with high initial levels of cement-floor coverage benefitted significantly less from Piso Firme’s intervention. These findings are discussed in greater detail on International Initiative for Impact Evaluation’s (3ie) working paper version. 相似文献
219.
Maria Papadakis 《Journal of policy analysis and management》1994,13(1):1-20
Much policymaking in the 1980s at the federal, state, and local levels tried to redress the U.S. competitiveness crisis. A guiding presumption was that there was a sudden and profound inability of the United States to compete in manufactured goods. However, there has been little systematic analysis of American competitive performance disaggregated for the entire manufacturing sector. Data analyzed here for the years 1970–1990 and for the 24 major two-and three-digit ISIC industries reveals that there was a competitiveness crisis in the 1980s, but it was not endemic to all industries. Market share, trade balance, and revealed comparative advantage indicators suggest the crisis was characterized by intensified competitive decline for the auto, textiles, and electronics, industries, and by competitive reversals for the electrical machinery and office and computing machine industries. While many other major American industries appear to be in competitive health, the cumulative effect of macroeconomic imbalances is likely to cause future competitive stress in the capital goods and high-technology sectors. 相似文献
220.
Griffith Michael A. Dubow Eric F. Ippolito Maria F. 《Journal of youth and adolescence》2000,29(2):183-204
In this study, we investigated developmental and cross-situational differences in strategies adolescents use to cope with family, school, and peer stressors. We also examined the relation between adolescents' use of coping strategies and two indices of adjustment (self perceptions of their adjustment as a result of coping with the specific stressor and state anxiety). The sample included 148 seventh graders, 124 ninth graders, and 103 twelfth graders (n = 375). Approach coping increased across the three grade levels, especially in relation to family and peer stressors. Adolescents used more avoidance than approach coping strategies for family stressors, and more approach than avoidance strategies for school and peer stressors. Across stressors, approach coping predicted more favorable outcomes and avoidance coping predicted less favorable outcomes. Coping strategies in response to a specific stressor were more strongly predictive of stressor-specific adjustment than state anxiety, suggesting the need to include both stressor-specific and global measures of adjustment in assessing the relation between coping and adjustment. 相似文献