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241.
The profound socio-political crisis in El Salvador fully revealed itself in the events of 1979 and 1980, developing into an open civil war beginning on 10 January 1981. The conflict generated a series of profound changes in the social structure of the country (Segundo Montes, 1988:107). 相似文献
242.
Atika Khurana Daniel Romer Laura M. Betancourt Hallam Hurt 《Journal of youth and adolescence》2018,47(9):1992-2005
Developmental imbalance models attribute the rise in risk-taking during adolescence to a universal imbalance between rising reward sensitivity and lagging cognitive control. This study tested predictions of an alternate Lifespan Wisdom Model that distinguishes between exploratory/adaptive (e.g., sensation seeking) and maladaptive (e.g., acting-without-thinking, delay discounting) risk-taking propensities and attributes the latter to a sub-set of youth with weak cognitive control. Latent trajectory modeling of six waves of data from 387 adolescents (52% females; spanning average ages of 11–18 years) revealed distinct sub-groups with heterogeneous trajectory patterns for acting-without-thinking and delay-discounting. Only those trajectory groups with weak cognitive control, characterized as “high-increasing” acting-without thinking and “high-stable” delay discounting were predictive of a maladaptive risk-taking outcome, namely substance use disorder. Sensation seeking demonstrated a universal peak, but high levels of sensation seeking were not associated with weakness in cognitive control and were unrelated to substance use disorder, controlling for impulsivity. The findings suggest that maladaptive risk-taking characterized by weak cognitive control over reward-driven impulses is a phenomenon limited to only a sub-set of youth. 相似文献
243.
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
244.
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
245.
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
246.
247.
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
248.
Jolien Trekels Kathrin Karsay Steven Eggermont Laura Vandenbosch 《Journal of youth and adolescence》2018,47(7):1440-1455
Although media exposure has been related to cognitive preoccupation with appearance, research rarely investigated adolescents’ behavioral self-sexualization. To address this gap, the present study among 12- to 16-year-olds (N?=?1527; 50.2% girls) in Austria, Belgium, Spain, and South-Korea (1) investigates whether different types of media use relate to self-sexualization, (2) explores the explanatory value of rewarded appearance ideals, and (3) considers culture and gender as moderating factors. Despite cultural variation, a general trend of increasing self-sexualization with social media use and magazine reading appeared across the countries. Moreover, women’s magazine reading and rewards were related to self-sexualization among all the girls across the countries, which suggests that girls may be more vulnerable to the examined effects. Overall, this study provides a better understanding of the unique contribution of specific media genres to youth’s self-sexualization and points at the importance of social media use in girls’ and boys’ engagement in sexualizing appearance behaviors across four countries. 相似文献
249.
Laura M. Padilla-Walker Sarah M. Coyne Savannah L. Kroff Madison K. Memmott-Elison 《Journal of youth and adolescence》2018,47(2):445-459
The goal of the current study was to examine the protective role that maternal media monitoring might have for adolescents. This was done by considering whether styles of media monitoring either directly reduced media use, or whether they buffered the associations between aggressive media use and adolescents’ prosocial behavior, aggression, and delinquency. Participants were 681 adolescents from two cities in the United States (51% female; 73% white), and their mothers, who provided data at two different time points, 2 years apart (when adolescents were roughly ages 13 and 15). Mixture modeling results revealed that mothers used four different styles of media monitoring made up of combinations of active and restrictive monitoring as well as forms of co-use. Styles that included active monitoring and connective co-use (i.e., engaging in media with the intent to connect with children) were directly associated with less media use, and moderated links between adolescents’ media use and behavioral outcomes concurrently but not longitudinally. The discussion was focused on the strength of considering multiple strategies of media monitoring together, and how this approach can inform future research in the area of parental media monitoring. 相似文献
250.
Robert G. Wallace 《Capitalism Nature Socialism》2018,29(3):21-35
In the second of our two-part review of Vladimir Lenin’s 1917 study of American agriculture, we extrapolate upon Alexander Chayanov’s neoliberal appropriation, Giovanni Arrighi’s treatment of partial proletarianization, the propagandistic “family farm,” agribusiness’s fluctuating territorial embeddedness, agriculture as an industry, and land and rent as commodities themselves. We finish by deploying Lenin’s alternate history as a Benjaminian détournement in the face of what now appear insurmountable obstacles. An alternate food future is not only possible, it is already underway. 相似文献