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201.
Many studies in the literature have highlighted the utility of virtual 3D databanks as a substitute for real skeletal collections and the important application of radiological records in personal identification. However, none have investigated the accuracy of virtual material compared to skeletal remains in nonmetric variant analysis using 3D models. The present study investigates the accuracy of 20 computed tomography (CT) 3D reconstruction models compared to the real crania, focusing on the quality of the reproduction of the real crania and the possibility to detect 29 dental/cranial morphological variations in 3D images. An interobserver analysis was performed to evaluate trait identification, number, position, and shape. Results demonstrate a false bone loss in 3D models in some cranial regions, specifically the maxillary and occipital bones in 85% and 20% of the samples. Additional analyses revealed several difficulties in the detection of cranial nonmetric traits in 3D models, resulting in incorrect identification in circa 70% of the traits. In particular, pitfalls included the detection of erroneous position, error in presence/absence rates, in number, and in shape. The lowest percentages of correct evaluations were found in traits localized in the lateral side of the cranium and for the infraorbital suture, mastoid foramen, and crenulation. The present study highlights important pitfalls in CT scan when compared with the real crania for nonmetric analysis. This may have crucial consequences in cases where 3D databanks are used as a source of reference population data for nonmetric traits and pathologies and during bone-CT comparisons for identification purposes.  相似文献   
202.
In the face of the discourse about the democratic deficit and declining public support for the European Union (EU), institutionalist scholars have examined the roles of institutions in EU decision making and in particular the implications of the empowered European Parliament. Almost in isolation from this literature, prior research on public attitudes toward the EU has largely adopted utilitarian, identity and informational accounts that focus on individual-level attributes. By combining the insights from the institutional and behavioural literature, this article reports on a novel cross-national conjoint experiment designed to investigate multidimensionality of public attitudes by taking into account the specific roles of institutions and distinct stages in EU decision making. Analysing data from a large-scale experimental survey in 13 EU member states, the findings demonstrate how and to what extent the institutional design of EU decision making shapes public support. In particular, the study finds a general pattern of public consensus about preferred institutional reform regarding powers of proposal, adoption and voting among European citizens in different countries, but notable dissent about sanctioning powers. The results show that utilitarian and partisan considerations matter primarily for the sanctioning dimension in which many respondents in Austria, the Czech Republic, Denmark and Sweden prefer national courts to the Court of Justice of the EU.  相似文献   
203.
Novel psychoactive substances (NPS) are synthetic drugs that pose serious public health and safety concerns. A multitude of NPS have been identified in the United States, often implicated in forensic investigations. The most common and effective manner for identifying NPS is by use of mass spectrometry and the true utility lies within nontargeted acquisition techniques. During this study, a liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) assay was developed, validated, and implemented for forensic toxicology testing. A SCIEX TripleTOF™ 5600 + with SWATH® acquisition was used. Resulting data were compared against an extensive library database containing more than 800 compounds. The LC-QTOF-MS assay was applied to the reanalysis of biological sample extracts to discover emergent NPS. More than 3,000 sample extracts were analyzed, and more than 20 emerging NPS were detected for the first time. Among these were isopropyl-U-47700, 3,4-methylenedioxy-U-47700, fluorofuranylfentanyl, N-methyl norfentanyl, 2F-deschloroketamine, 3,4-methylenedioxy-alpha-PHP, eutylone, and N-ethyl hexedrone.  相似文献   
204.
205.
Journal of Youth and Adolescence - Adolescence tends to be characterized by a temporary peak in delinquent behavior, and friends in particular play a key role in the initiation and the development...  相似文献   
206.
This article explores the construction of extremism in media discourse, the factors driving specific constructions and the implications of these constructions for counterterrorism policy. We contend that extremism has predominantly and increasingly been framed as a security issue. This article explores the implications of this practice through the framework of securitisation. We measure the average intensity of security framing in 38,616 articles found in three major US newspapers, New York Times, Wall Street Journal and Los Angeles Times, between 20 January 1993 and 19 January 2017 comprising the Clinton, Bush and Obama presidencies, and look at factors influencing the shift in intensity over time. Through our analysis, we show that it is possible to return to a pre-9/11 discourse but that the confluence of real-world events and the strategic choices of political actors have so far prevented this from fully occurring. We then explore the effect of securitisation on public perceptions of the threat from terrorism, finding that increases in the intensity of security framing artificially increases the public’s worry about becoming a victim of terrorism. We conclude by discussing implications for the communication of counterterrorism policy and the requirements for an after, after 9/11 approach  相似文献   
207.
The problem‐solving capacity and problem‐generating potential of multilevel systems entail the need for the delegation of authority. When the problem concerned is about how to put an abstract policy concept into a practicable policy tool, the choice of the respective delegation trajectory depends on the policy models or the policy‐relevant knowledge that the respective political levels can supply. When regarding the European Union (EU) level as the starting point of knowledge creation and delegation trajectories, and concentrating on transaction costs, policy knowledge and models generated at the international level provide the most cost‐effective solution. Only when the international level is not able to provide further policy knowledge and innovation does the EU delegate its definitional authority, first downward to the member states and then sideways to EU agencies. We illustrate the plausibility of our dynamic understanding of multilevel governance by using Environmental Policy Integration as an example.  相似文献   
208.
The understanding of positive development across adolescence rests on having a valid and equivalent measure of this construct across the breadth of this period of life. Does the Positive Youth Development (PYD) construct based on the Five Cs model have satisfactory psychometric properties for such longitudinal measurement invariance? Using longitudinal data derived from the 4-H Study of PYD, we assessed 920 youth (61.6% female) from a racially and ethically diverse sample (67.3% European American) who participated in three waves (Grades 8–10) of data collection. Building on prior findings that the Five Cs (i.e., Competence, Confidence, Connection, Character, and Caring) model of PYD was a robust measure that could be assessed comparably during early adolescence, we tested a hierarchy of second-order confirmatory factor analysis models to assess the extent to which PYD can be measured equivalently across middle adolescence. Evidence was found for strict measurement invariance across three measurement occasions, including equivalence of first-order and second-order factor loadings, equality of intercepts of observed variables, and equality of item uniqueness and disturbances of the first-order factors. These results suggest that PYD can be measured in the same way across measurement occasions, a prerequisite for the study of development. Implications for research and application of being able to measure PYD equivalently across adolescence are discussed.  相似文献   
209.
While the financial crisis of 2008 ultimately affected the range of U.S. financial institutions, it began with practices in home ownership finance. The Federal Home Loan Bank (FHLBank) System was the first instrumentality created by the U.S. government, in 1932, to sustain affordable home ownership finance. In this article, the authors ask what role, if any, the FHLBanks played in the subprime lending and securitization practices that precipitated the current crisis. The authors analyze publicly available FHLBank financial data in terms of a framework focused on the System's assets: advances; mortgage loans acquired from members; and investments, particularly in mortgage-backed-securities. They conclude that the FHLBanks did not contribute significantly to problematic practices. Nonetheless, they recommend consideration of three reforms to the FHLBanks to ensure a return to effective regulation and responsible, affordable home ownership finance.  相似文献   
210.
Using a panel dataset of privatized cement firms in Turkey, this paper models and finds support for the simultaneous relationship between privatization and firm performance. It is found that favorable short-run performance, weak market potential, higher employment, lower socio-economic development, concentrated voter preferences, and weaker representation of right-wing parties in the firms’ locality delay the timing of privatization. The paper also finds that privatization increases output in the medium-term by reducing the labor stock and promoting the adoption of more advanced technology, such that production shifts from constant to decreasing returns to scale.  相似文献   
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