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241.
Nicole A. Anderson Amy M. Bohnert Amy Governale 《Journal of youth and adolescence》2018,47(8):1697-1711
Research examining factors that predict youth’s involvement in organized activities is very limited, despite associations with positive outcomes. Using data from 1043 youth (49% female; 46.4% Hispanic, 35.4% African American, 14.0% Caucasian, and 4.2% other) from the Project on Human Development in Chicago Neighborhoods, this study examined how characteristics of parents (supervision, warmth) and neighborhoods (perceived neighborhood safety and collective efficacy) predict patterns of adolescents’ involvement in organized activities concurrently (i.e., intensity) and longitudinally (i.e., type and breadth). Parental supervision predicted adolescents’ participation in organized activities across multiple waves. Neighborhood violence was positively associated with concurrent participation in organized activities after controlling for socioeconomic status (SES), whereas higher neighborhood collective efficacy predicted greater breadth in organized activity participation across time. These findings have important implications regarding how to attract and sustain organized activity participation for low-income, urban youth. 相似文献
242.
R G Gullberg 《Journal - Forensic Science Society》1989,29(6):397-405
A breath alcohol profile is generated as a continuous function of time while a person is providing a breath sample. This paper describes a data acquisition system which samples breath alcohol concentrations at discrete intervals during exhalation. The data are stored on disk for later analysis. It is shown that the area under the profile curve for samples preceded by breath-holding is significantly larger than when breathing is normal prior to sample provision (p less than 0.001). The differences between the breath alcohol concentration measurements are also statistically significant (p less than 0.001) for the two different breathing patterns prior to breath exhalation. These results have physiological implications and suggest another means of evaluating breath alcohol profiles. 相似文献
243.
244.
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
245.
African agriculture is often dominated by smallholder farms composed of multiple plots. In policy circles it is often assumed that fragmentation coupled with small farm size is an impediment to increasing yields and thus decreasing poverty and food insecurity. There also exists an influential literature that explores the inverse relationship between farm size and yield. While there are many studies internationally, few have been conducted in Africa. Using an Ethiopian national survey, we explore the relationship between yield, farm size and fragmentation. We find an inverse relationship between farm size and yield, and a positive association between yield and land fragmentation. 相似文献
246.
Ashlesha Khadse Peter Michael Rosset Helda Morales Bruce G. Ferguson 《The Journal of peasant studies》2018,45(1):192-219
This paper analyzes how peasant movements scale up agroecology. It specifically examines Zero Budget Natural Farming (ZBNF), a grassroots peasant agroecology movement in Karnataka, India. ZBNF ends reliance on purchased inputs and loans for farming, positioning itself as a solution to extreme indebtedness and suicides among Indian farmers. The ZBNF movement has achieved massive scale not only because of effective farming practices, but because of a social movement dynamic – motivating members through discourse, mobilizing resources from allies, self-organized pedagogical activities, charismatic and local leadership, and generating a spirit of volunteerism among its members. This paper was produced as part of a self-study process in La Via Campesina, the global peasant movement. 相似文献
247.
248.
The Covid-19 pandemic has revealed and accelerated an information crisis as well as a health one. What we discover about Covid 19, how it spreads, to whom and why and how best to mitigate it—all depend on information. The essays in this special section, which this article introduces, explore the importance of information and the fundamental role of fact checkers in understanding how information flows, why mistakes are made, and how to counteract them. Fact checking as an idea and a practice emerged in the early twenty-first century, developed as a positive beacon to counteract a growing sense that information could no longer be trusted. Now, more than a decade after its creation, fact checking sits within a far more complex and chaotic media context, and its expertise and understanding has never been so important. We need to understand what fact checkers do because they are grappling with how to tether us to reality. 相似文献
249.
This paper examines the power to prorogue (or suspend) Parliament following the 2019 prorogation controversy in the UK. We outline the legal basis of prerogative-based prorogation, survey its uses in the UK and other Westminster systems, and compare it with equivalent rules in other European parliamentary democracies. The comparative perspective highlights the outlier status of the UK among comparable European democracies. In the UK, the absence of explicit legal limits on the use of prorogation gives the executive exceptional scope to employ the power for political purposes to sidestep Parliament. We conclude by discussing the implications of these findings for current discussions about the desirability of reforming the UK’s prorogation rules and placing express legal limits on the executive’s power. 相似文献
250.
This article explores how the UK’s fact-checking organisation Full Fact has sought to tackle misinformation since its inception in 2010. Full Fact describes itself as a ‘second generation’ fact-checking organisation with dual aims of seeking to stop the spread of specific pieces of inaccurate information and using the evidence base from fact checking to secure systemic changes that help make misinformation rarer and less harmful. Ultimately, we are pursuing culture change. We are trying to create institutions in societies that can help anchor public debate to reality and to challenge the casual acceptance of deceptive and misleading behaviour. 相似文献