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151.
A new political geography has emerged in the Middle East and North Africa (MENA) after the Arab Spring. The transformative impact of the popular upheavals appeared to put an end to long-term authoritarian regimes. Today, the region is far from stable since authoritarian resilience violently pushed back popular demands for good governance and is pushing to restore former state structures. However, the collective consciousness of the popular revolts endures, and a transformative prospect may emerge on the horizon. The chaotic situation is the result of an ongoing struggle between those who seek change and transformation and others in favour of the status quo ante. A critical evaluation of the Arab Spring after five years indicates a continuous process of recalculation and recalibration of policies and strategies. There are alternative routes for an eventual settlement in the MENA region, which are in competition against both regional and transregional quests for a favourable order.  相似文献   
152.
Richard Sakwa 《欧亚研究》2016,68(6):1102-1104
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153.
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   
154.
155.
Journal of Experimental Criminology - This paper reports a quasi-experimental evaluation of California’s 1996 medical marijuana law (MML), known as Proposition 215, on statewide motor vehicle...  相似文献   
156.
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   
157.
Extracurricular activities provide a key context for youth development, and participation has been linked with positive developmental outcomes. Using data from the 4-H Study of Positive Youth Development (PYD), this study explored how the intentional self regulation ability of youth interacted with participation in extracurricular activities to affect PYD among adolescents living in neighborhoods with relatively low ecological assets. In total, 545 youth were included in the study (50.3% female). Most of the youth were European American (41%) or Latino (37%; African American, 10%; Asian American, 7%; Native American, 4%; and other, 1%). In general, youth with the greatest capacity to self regulate benefitted the most, as compared to their peers with less capacity to self regulate, from involvement in extracurricular activities. Consistent with a developmental systems perspective, and specifically with bioecological theory, the findings from this study confirmed that, within lower asset settings, children with the most positive person-level factors (intentional self regulation) benefit the most from proximal processes such as extracurricular activity involvement.  相似文献   
158.
Few studies have examined risk factors of childhood and early adolescent depressive symptomatology trajectories. This study examined self-report depressive symptomatology across a 6-year time period from 2nd to 8th grade to identify latent groups of individuals with similar patterns of depressive phenomena in a sample of 951 children (440 girls, 511 boys). Analyses, using semiparametric group modeling (SGM), identified 5 trajectory groups for girls and boys: low depressed stables, low depressed risers, mildly depressed stables, moderately depressed changers, and moderately depressed risers. Individual risk factors, with the exception of shy/withdrawn behavior, were significantly different across trajectory group membership for boys and girls, as was low-income status for boys. Boys in the low depressed and mildly depressed stable trajectory groups had significantly higher levels of antisocial behavior, attention problems, and lower social competency compared to girls in similar groups. These results suggest that universal prevention programs implemented in early elementary school that target selected risk factors may be helpful in reducing future adolescent mental health problems, specifically depressive symptomatology.  相似文献   
159.
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   
160.
Intentional self regulation describes how people make choices, plan actions to reach their goals, and regulate the execution of their actions, making processes of intentional self regulation central to healthy human functioning. Prior research has confirmed the presence of three processes of intentional self regulation—elective selection (ES), optimization (O), and compensation (C)—in middle adolescence (Grades 8 through 10) and concurrent and predictive relationships with measures of Positive Youth Development (PYD). A fourth process, loss-based selection (LBS), should also develop by the end of middle adolescence. The present study used data from the 4-H Study of PYD to confirm the presence of a four-scale structure of intentional self regulation (ES, O, C, and LBS) in a sample of 2,357 racially diverse Grade 10 youth (63% female) and examine its covariation with indicators of positive and problematic development. Results supported the identification of a four-part structure of intentional self regulation, and scores covaried positively with indicators of PYD and negatively with substance use, delinquency, and depressive symptoms. Implications of the findings for the understanding of self-regulatory actions in adolescence and for future research are discussed.  相似文献   
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