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981.
The “Arab Spring” was a surprising event not just because predicting revolutions is a difficult task, but because current theories of revolution are ill equipped to explain revolutionary waves where interactive causal mechanisms at different levels of analysis and interactions between the units of analysis predominate. To account for such dynamics, a multidimensional social science of revolution is required. Accordingly, a meta-framework for revolutionary theory that combines multiple levels of analysis, multiple units of analysis, and their interactions is offered. A structured example of theory building is then given by detailing how the development of world cultural models and practices challenge existing political structures, affect mobilization processes, and make diffusion more likely. A structured example of study design using qualitative comparative analysis of 16 Middle Eastern and North African countries provides support for the interaction of subnational conditions for mobilization, state-centered causes, and transnational factors, including a country’s linkage to world society, as one explanation of the Revolutions of 2011.  相似文献   
982.

Life satisfaction can be assessed either globally or with regard to satisfaction with specific domains of life. The latter multidimensional approach presumes science has delineated with confidence the specific domains most relevant to evaluating whether the criteria for a good life have been met. This paper shares results of a qualitative study of the perceived determinants of life satisfaction among 30 high school students who were diverse in terms of mental health; 6–10 participants were classified as complete mental health, vulnerable, symptomatic but content, or troubled at two time points separated by a year. Thematic analyses of transcribed individual interviews suggested eight themes that capture the domains of life adolescents perceive influence their happiness. These themes are compared and contrasted to domains included in existing multi-dimensional measures of youth life satisfaction. The factors likely to be particularly salient to students with different levels of mental health are noted.

  相似文献   
983.
This paper draws on a survey design to investigate whether family ownership and leadership have an influence on the decision-facilitating and decision-influencing roles of management control. Moreover, we investigate whether the more intuitive decision making in family firms which is often said to be caused by a lack of professionalism, is indeed a disadvantage. The results indicate significant differences in the use of management controls between family firms and non-family firms. However, in contrast to the prevailing view in literature, the performance of family firms is not affected negatively by their specific way of making decisions and by their more centralized management style. According to our data, the prevailing characterization of family firms as being less professionally managed seems questionable.  相似文献   
984.
Current state and national mandates focusing on academic achievement have drawn critical counseling resources away from career development. As the world of work radically changes and economic situations remain uncertain, the call for a return to school counseling roots based in career guidance has never been louder. The authors explore reoccurring career guidance trends throughout the history of school counseling to expand awareness of the basis of today's career and technical education discussions and increase understanding of the interconnectedness of career guidance and counseling and educational reform.  相似文献   
985.
Many European countries during the 1990s and early 2000s tried to raise labor market flexibility by relaxing their employment protection legislation. This paper investigates whether the reforms have influenced job and employment stability for labor market entrants in Germany and Italy. Duration models are estimated using comparable administrative data for the two countries. The results provide, to some extent, evidence of a decrease in job stability. However, this is not accompanied by a compensating increase in employment stability during the first 3 years after labor market entry.  相似文献   
986.
987.
This paper examines the goals of organizations that sponsor short-term volunteer trips in global health, whether they be NGO’s, faith-based, educational, or corporate organizations. Results from a U.S.-based national survey of 177 such organizations and 27 interviews with trip organizers suggest that organizations often sponsor volunteer trips to achieve goals that are quite different from the improvement of health outcomes in poor countries. While providing health services is often cited as the most important goal, volunteer activity is also considered important in enhancing the organizations’ reputation, recruitment and retention, and financial well-being. The prominence of other goals has the potential for diverting resources and focus from what is presumably the primary purpose of serving host communities in the most effective manner possible.  相似文献   
988.
In response to water quality standard violations linked to excessive organic matter (OM) and a lack of sampling data informing the Total Maximum Daily Load (TMDL), an organic matter budget was created to quantify and identify sources of OM in the lower Jordan River (Salt Lake City, UT). By sampling dissolved, fine and coarse particulate OM, as well as measuring ecosystem metabolism at seven different sites, the researchers aimed to identify the origin of excess OM, and understand pathways by which different size classes of the OM pool are generated. The dissolved fraction (DOM; 94 %) was found to be the dominant form of OM transported within the river with fine particulate organic matter (FPOM; 6 %) the second most abundant, and coarse particulate organic matter (CPOM; 1 %) transport relatively insignificant in the overall OM budget. Primary production exceeded respiratory losses in the upper river, and this, along with OM inputs from two tributaries (where water reclamation facilities discharge into the river) delivered excess OM to the impaired lower reaches. Increasing stream metabolism index (SMI) with distance downstream (>1 in the lower river) further demonstrated that transport of excessive organic matter into the lower river was from upstream sources and not due to lateral inputs. This simple approach to characterizing the organic matter budget as it relates to water quality in the Jordan River was effective and could serve as a model for future studies attempting to quantify and identify sources of OM in urban ecosystems.  相似文献   
989.
We treat robust M-estimators for independent and identically distributed Poisson data. We introduce modified Tukey M-estimators with bias correction and compare them to M-estimators based on the Huber function as well as to weighted likelihood and other estimators by simulation in case of clean data and data with outliers. In particular, we investigate the problem of combining robustness and high efficiencies at small Poisson means caused by the strong asymmetry of such Poisson distributions and propose a further estimator based on adaptive trimming. The advantages of the constructed estimators are illustrated by an application to smoothing count data with a time varying mean and level shifts.  相似文献   
990.
Sam V. Wass  Tim J. Smith 《Infancy》2014,19(4):352-384
Little research hitherto has examined how individual differences in attention, as assessed using standard experimental paradigms, relate to individual differences in how attention is spontaneously allocated in more naturalistic contexts. Here, we analyzed the time intervals between refoveating eye movements (fixation durations) while typically developing 11‐month‐old infants viewed a 90‐min battery ranging from complex dynamic to noncomplex static materials. The same infants also completed experimental assessments of cognitive control, psychomotor reaction times (RT), processing speed (indexed via peak look during habituation), and arousal (indexed via tonic pupil size). High test–retest reliability was found for fixation duration, across testing sessions and across types of viewing material. Increased cognitive control and increased arousal were associated with reduced variability in fixation duration. For fixations to dynamic stimuli, in which a large proportion of saccades may be exogenously cued, we found that psychomotor RT measures were most predictive of mean fixation duration; for fixations to static stimuli, in contrast, in which there is less exogenous attentional capture, we found that psychomotor RT did not predict performance, but that measures of cognitive control and arousal did. The implications of these findings for understanding the development of attentional control in naturalistic settings are discussed.  相似文献   
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