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821.
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
822.
A continuous model for interpreting the positions of bands in DNA locus-specific work. 总被引:1,自引:0,他引:1
A simple but rigorous approach is offered for evaluating the evidential value of single locus DNA autoradiographs. This approach does not use a binning technique and it does not treat alleles as discrete variables. Instead, the allele distribution is considered to be continuous. The variation between two comparable bands is assessed using previously determined experimental parameters. The Bayesian treatment leads to an expression of the "quality of a match". 相似文献
823.
Postmortem stability of DNA 总被引:11,自引:0,他引:11
High-molecular-weight DNA was recovered postmortem in sufficient quantities from various human organ tissues as well as from blood, although not all organs were equally well suitable. Good DNA stability was found in brain cortex, lymph nodes and psoas muscle over a period of three weeks postmortem. Spleen and kidney showed good DNA stability up to five days postmortem but after longer periods, rapid degradation was observed. Yields of DNA from blood were not consistent because of the non homogeneity of samples. Blood clots were rich with DNA. Generally, the amount of degraded DNA correlated directly with the duration of the postmortem period. However in some cases, DNA degradation was already prominent after a short period. However in some cases, DNA degradation was already prominent after a short period. Case histories showed that high environmental temperature at the site of death and/or infectious diseases prior to death were the main factors for rapid autolysis. Gradual disappearance to complete loss of the long fragments (15-23 kb) was observed in DNA fingerprinting using the minisatellite probe 33.15. No extra-bands were noted, thus excluding erroneous conclusions. However, evidentiary value of older samples was lower. 相似文献
824.
825.
The polymorphism of the human vitamin D binding protein (Gc system) was investigated in a total of 149 sera from unrelated healthy Egyptians residing in Tanta City, Gharbiya Governorate, Nile Delta of Egypt, using isoelectric focusing (IEF) in thin-layer polyacrylamide gel followed by immunoblotting. The estimated gene frequencies were Gc1s = 0.540, Gc1f = 0.242 and Gc2 = 0.218. 相似文献
826.
Naoise Mac Giollabhui Johanna Nielsen Sam Seidman Thomas M. Olino Lyn Y. Abramson Lauren B. Alloy 《Journal of youth and adolescence》2018,47(10):2129-2142
Hopelessness is implicated in multiple psychological disorders. Little is known, however, about the trajectory of hopelessness during adolescence or how emergent future orientation may influence its trajectory. Parallel process latent growth curve modelling tested whether (i) trajectories of future orientation and hopelessness and (ii) within-individual change in future orientation and hopelessness were related. The study was comprised of 472 adolescents [52% female, 47% Caucasian, 47% received free lunch] recruited at ages 12–13 who completed measures of future orientation and hopelessness at five annual assessments. The results indicate that a general decline in hopelessness across adolescence occurs quicker for those experiencing faster development of future orientation, when controlling for age, sex, low socio-economic status in addition to stressful life events in childhood and adolescence. Stressful childhood life events were associated with worse future orientation at baseline and negative life events experienced during adolescence were associated with both an increase in the trajectory of hopelessness as well as a decrease in the trajectory of future orientation. This study provides compelling evidence that the development of future orientation during adolescence is associated with a faster decline in hopelessness. 相似文献
827.
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
828.
AliceAnn Crandall Brianna M. Magnusson M. Lelinneth B. Novilla 《Journal of youth and adolescence》2018,47(4):793-806
Adolescent self-regulation is increasingly seen as an important predictor of sexual risk-taking behaviors, but little is understood about how changes in self-regulation affect later sexual risk-taking. Family financial stress may affect the development of self-regulation and later engagement in sexual risk-taking. We examined whether family financial stress influences self-regulation in early adolescence (age 13) and growth in self-regulation throughout adolescence (from age 13–17 years). We then assessed the effects of family financial stress, baseline self-regulation, and the development of self-regulation on adolescent sexual risk-taking behaviors at age 18 years. Using a curve-of-factors model, we examined these relationships in a 6-year longitudinal study of 470 adolescents (52% female) and their parents from a large northwestern city in the United States. Results indicated that family financial stress was negatively associated with baseline self-regulation but not with growth in self-regulation throughout adolescence. Both baseline self-regulation and growth in self-regulation were predictive of decreased likelihood of engaging in sexual risk-taking. Family financial stress was not predictive of later sexual risk-taking. Intervening to support the development of self-regulation in adolescence may be especially protective against later sexual risk-taking. 相似文献
829.
Using interview and survey data, we argue there are three types of places in the rural United States, and that their social and economic conditions help us understand emerging political trends, including the rural support for Donald Trump. More rural votes were cast for the Republican presidential candidate in 2016 than in other recent elections, yet shifts to Republican votes were greatest in places undergoing the most significant economic transitions. Work in rural communities has been a source of pride and cultural identity for people as well as places, but many feel the new economy is not working for them. 相似文献
830.
Ian Scoones Marc Edelman Saturnino M. Borras Jr. Ruth Hall Wendy Wolford Ben White 《The Journal of peasant studies》2018,45(1):1-20
A new political moment is underway. Although there are significant differences in how this is constituted in different places, one manifestation of the new moment is the rise of distinct forms of authoritarian populism. In this opening paper of the JPS Forum series on ‘Authoritarian Populism and the Rural World’, we explore the relationship between these new forms of politics and rural areas around the world. We ask how rural transformations have contributed to deepening regressive national politics, and how rural areas shape and are shaped by these politics. We propose a global agenda for research, debate and action, which we call the Emancipatory Rural Politics Initiative (ERPI, www.iss.nl/erpi). This centres on understanding the contemporary conjuncture, working to confront authoritarian populism through the analysis of and support for alternatives. 相似文献