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191.
Brian D. Christens Kymberly Byrd N. Andrew Peterson David T. LardierJr. 《Journal of youth and adolescence》2018,47(8):1649-1662
Psychological empowerment encompasses several key aspects of youth civic and sociopolitical development. Most research has focused on psychological empowerment’s emotional component, which entails learned hopefulness about one’s own ability to participate in and lead community change efforts. Fewer studies have assessed critical awareness of how social power operates—psychological empowerment’s cognitive component. The confluence of these two components has been termed critical hopefulness. A complex relationship exists between these two components, and previous research has found relatively small proportions of participants reporting both high levels of critical awareness and simultaneously high levels of hopefulness about their ability to exert influence in the sociopolitical domain. The current study of urban high school students in the Northeastern U.S. (n?=?389; 53.5% female) investigates heterogeneity according to these two components of psychological empowerment. Latent class cluster analyses were conducted and seven distinct groups of participants emerged. Students identifying as Hispanic/Latinx were more likely to be classified into a profile group exhibiting critical hopefulness. Differences were observed between psychological empowerment profile groups on self-reported levels of psychological sense of community, civic engagement, and social justice orientation. Furthermore, a larger proportion of this overall sample was classified into groups that exhibited critical hopefulness than in a previous study of adults. These findings provide useful insights for efforts to engage young people in civic life and to promote sociopolitical development. 相似文献
192.
Document examiners sometimes eliminate writers on the basis of differences which are given too much weight. This article is an attempt to explain some conditions whereby differences in the writing of one individual are misinterpreted as significant differences, when they are actually caused by conditions which are unknown to the examiner. 相似文献
193.
The activity of calcium pumping adenosine triphosphatase (Ca2+-ATPase) in cardiac sarcoplasmic reticulum plays a pivotal role in myocardiac contraction-relaxation. The Ca2+-ATPase activity is controlled by phosphorylation and dephosphorylation of a sarcoplasmic reticulum protein "phospholamban" in response to neurotransmitters and drugs. To clarify the role of Ca2+-ATPase in the development of cardiac rigor mortis, we examined the changes of cardiac rigidity and cardiac sarcoplasmic reticulum Ca2+-ATPase activity up to 5 h after the decapitation of rats. Fifteen minutes after decapitation, the rats showed a cardiac rigidity on left ventricles. After 30 min, rigidity was obvious over the whole heart. After 1 h, the rigidity reached a high degree which was maintained for the rest of the observation period. On the other hand, the Ca2+-ATPase activity controlled by phosphorylation and dephosphorylation of phospholamban did not change for the whole observation period (5 h). Another Ca2+-ATPase activity representing the total amount of Ca2+-ATPase in sarcoplasmic reticulum gradually decreased. The data suggest that no significant phosphorylation or dephosphorylation of phospholamban occurs for a short time, at least for 5 h, after death and that the Ca2+-ATPase tends to relax the myocardium against the development of cardiac rigor mortis. 相似文献
194.
T Karlsmark H K Thomsen L Danielsen O Aalund O Nielsen K G Nielsen I K Genefke 《Forensic science international》1988,39(2):175-188
In order to establish pathological evidence in dermis for distinguishing between sequelae of electrical torture and those of other superficial injuries, the skin of eleven fully anaesthetized Danish Landrace pigs have been exposed to heat and electrical energy from either 50 Hz alternating current (a.c.) or direct current (d.c.) via 12 mm large contact knobs or via a pointed 0.5 mm large electrode (only 50 Hz a.c.). The lesions have been examined from 1 to 126 days after the injury. While heat lesions exposed to energy lower than 60 joule only gave minor changes, heat lesions exposed to more than 60 joule showed changes in both collagen fibres (basophilic or eosinophilic fibres without any birefringence or coarse cross-striation in polarized light, respectively) and dermal cells (granular cytoplasm). Areas exposed to 50 Hz a.c. via 0.5 mm. electrode showed basophilic collagen fibres and in a few biopsies on day 7 calcium salts on collagen fibres. Using 12 mm large electrodes the changes were minor, but basophilic and eosinophilic collagen fibres with no birefringence or with fine/coarse cross-striation respectively were seen. Even cells with 'vesicular nuclei' were seen on day 1 and 2 after the injury. The changes in the anode area showed resemblance to that of heat lesions (basophilic collagen fibres). Eosinophilic collagen fibres with fine densely spaced cross-striation in polarized light and 'vesicular nuclei' as well as collagen fibres with calcium salts were seen in the cathode lesions. It is concluded that the dermal changes in the cathode area are specific for electrical injury from day 1 to 14. However, earlier studies have demonstrated dermal changes specific for electrical injury at day 0 and the presence of calcified collagen fibres up to 2 months after injury. The dermal changes in anode lesions were non specific and could not be differentiated from those found in heat lesions. Alternating current lesions (50 Hz) were specific from day 1 to day 7, when the pointed electrode was used, but only in a few days when the energy was transferred via the 12-mm electrodes. 相似文献
195.
Willy Pedersen Anders Bakken Tilmann von Soest 《Journal of youth and adolescence》2018,47(10):2073-2087
Little is known about the relative influences of neighborhood and school on the alcohol socialization process. Survey data from the Young in Oslo Study (N?=?10,038, mean age 17.1 years, 52% girls) were used to investigate the details of such influences, using cross-classified multilevel models. School and neighborhood contexts were equally important for ordinary alcohol use; however, neighborhood influences were mainly explained by individual and family factors, whereas peer-based sociocultural processes played a key role in explaining school effects. Neither context had much impact on heavy episodic drinking. The study suggests that “privileged” youth may be at risk of high alcohol consumption. Parental influences and peer-based sociocultural aspects of the school milieu should be considered in prevention efforts. 相似文献
196.
Against a backdrop of increased levels of marketization of welfare services in OECD countries, this article aims to shed light on the separate effects of private ownership and competition for the market on service quality. Using residential elder care homes in Sweden as our case, we leverage unique panel data of ownership and competition against a set of indicators, pertaining to the structure, process, and outcome dimensions of care quality. The main finding of our analyses is that competition for the market does surprisingly little for quality: private entrepreneurs perform neither better nor worse under stiff competition and the quality of care is approximately the same in those nursing homes that are exposed to the market as in those that are not. 相似文献
197.
Malaysians firms have made inroads into the non-traditional export markets. Such ventures are expected to result in increased knowledge about the marketing systems that are posited to be different from the traditional export markets. This paper reports on the perceived improvement in marketing competencies of Malaysian exporters. The results of data analysis show that there are five dimensions of marketing competency. In ranking order, segmenting and targeting competency is ranked highest followed by product management, export management, product differentiation and promotion. Multiple regression analysis was performed to test the explanatory power of each marketing competency on export performance of firms exporting to China and ASEAN countries. The result revealed that none of the marketing competency explained the variation in export performance for the China market. However, among exporters in ASEAN countries, it was noted that promotion competency resulted in a negative impact on both measures of export performance. Product competency is positively associated with financial measure of export performance. Competencies in segmenting and targeting, and export management are positively associated with non-financial performance. 相似文献
198.
Michael J. Cleveland Mark E. Feinberg Mark T. Greenberg 《Journal of youth and adolescence》2010,39(2):114-126
This study used data from a sample of 6th to 12th grade students (N = 48,641, 51% female), nested in 192 schools, to determine if the influence of family-based protective factors varied across
different school contexts. Hierarchical logistic regression models were used to examine the effects of individual-level family
protective factors, relative to school-level aggregates of the same factors, on recent (past 30 days) use of cigarettes, alcohol,
and marijuana. Cross-level interactions indicated that the effect of the student’s level of family protection, relative to
other students in their school, differed depending on the aggregated school level of family protection. The results suggested
that the benefit of belonging to a well-functioning family was more influential for students attending schools characterized
by higher-than-average aggregated levels of protection compared to students attending schools of lower-than-average protection.
Thus, family-level factors offered less protection for students in relatively high-risk school contexts. These results were
consistent with a protective–reactive interaction and suggest that a thorough understanding of adolescent substance use must
consider the complex interplay among adolescents, their families, and their social environments. 相似文献
199.
Tobias Jung Tim Scott Huw T. O. Davies Peter Bower Diane Whalley Rosalind McNally Russell Mannion 《Public administration review》2009,69(6):1087-1096
Organizational culture is widely considered to be one of the most significant factors in reforming and modernizing public administration and service delivery. This article documents the findings of a literature review of existing qualitative and quantitative instruments for the exploration of organizational culture. Seventy instruments are identified, of which 48 could be submitted to psychometric assessment. The majority of these are at a preliminary stage of development. The study's conclusion is that there is no ideal instrument for cultural exploration. The degree to which any measure is seen as "fit for purpose" depends on the particular reason for which it is to be used and the context within which it is to be applied. 相似文献
200.
Thomas T. Holyoke Jeffrey R. Henig Heath Brown Natalie Lacireno-Paquet 《Policy Sciences》2009,42(1):33-55
Baumgartner and Jones (1993) showed how radically new policies emerge on government agendas as a consequence of exogenous shocks to policy subsystems displacing privileged interests. But how do these policies evolve post-punctuation? In this paper, we present three different models of policy change. Policies may revert to the old status quo if displaced interests re-assert themselves, or they may be “locked-in” by new interests now reaping the benefits. Alternatively, they may incrementally change as lawmakers “learn” how to better meet target population needs, particularly by witnessing how other jurisdictions address similar problems. We test these models with data on change in state charter schools laws over time. We find that whether old status quos are overthrow, and the fate of charter policies when they are enacted, is influenced more by competing political interests, especially interest groups, than elite and public perceptions of broad systemic crises. Yet, we also find that changing demands on the state and learning from the successes and failures of neighboring states also play significant roles. 相似文献