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121.
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
122.
A method has been developed for the rapid extraction of cocaine and benzoylecgonine from post-mortem blood and urine samples. Solid phase columns containing C8 packing material gave clean, emulsion free extracts from body fluids. The total time for each extraction was approx. 10 min and the system has the capacity for the simultaneous extraction of up to 10 samples. Urine can be extracted directly, blood samples were sonicated before extraction to allow for their easy passage through the columns. The method gave excellent recoveries of cocaine (98-100%) from spiked samples at concentrations of between 50 ng/ml and 10 micrograms/ml. Analysis of the extracts was by high performance liquid chromatography (HPLC). 相似文献
123.
This paper describes a simplified approach to calculating the Bayesian likelihood ratio for the case where two DNA single locus profiles are to be compared. It explains how the calculation allows for band shift and also for the variation in precision with molecular weight. A simple basic theory section explains the principles of the analysis but more detailed explanations are given in an advanced theory section. Experiments on substantial data collections are described which demonstrate the robustness of the method. 相似文献
124.
A small experiment is described which uses databases of Afro-Caribbeans and Caucasians to establish the quality of information that might be given to an investigator about the ethnic group of the donor of an unknown crime stain. The results show that the technique can provide qualified indications, but categoric conclusions are not, in general, feasible. An appraisal is given of the technique within the operational context. 相似文献
125.
Christopher Cambron Rick Kosterman Richard F. Catalano Katarina Guttmannova J. David Hawkins 《Journal of youth and adolescence》2018,47(2):369-382
There is broad agreement that neighborhood contexts are important for adolescent development, but there is less consensus about their association with adolescent smoking and alcohol use. Few studies have examined associations between neighborhood socioeconomic contexts and smoking and alcohol use while also accounting for differences in family and peer risk factors for substance use. Data drawn from the Seattle Social Development Project (N?=?808), a gender-balanced (female?=?49%), multiethnic, theory-driven longitudinal study originating in Seattle, WA, were used to estimate trajectories of smoking and alcohol use from 5th to 9th grade. Time-varying measures of neighborhood socioeconomic, family, and peer factors were associated with smoking and alcohol use at each wave after accounting for average growth in smoking and alcohol use over time and demographic differences. Results indicated that living in more socioeconomically disadvantaged neighborhoods, lower family income, lower family general functioning, more permissive family smoking environments, and affiliation with deviant peers were independently associated with increased smoking. Lower family functioning, more permissive family alcohol use environments, and deviant peers were independently associated with increased alcohol use. The effect of neighborhood disadvantage on smoking was mediated by family income and deviant peers while the effect of neighborhood disadvantage on alcohol use was mediated by deviant peers alone. Family functioning and family substance use did not mediate associations between neighborhood disadvantage and smoking or alcohol use. The results highlight the importance of neighborhood, family, and peer factors in early adolescent smoking and alcohol use. Future studies should examine the unique association of neighborhood disadvantage with adolescent smoking net of family socioeconomics, functioning, and substance use, as well as peer affiliations. Better understanding of the role of contextual factors in early adolescent smoking and alcohol use can help bolster efforts to prevent both short and long harms from substance use. 相似文献
126.
Zachary Greene Jae-Jae Spoon Christopher J. Williams 《Journal of Elections, Public Opinion & Parties》2018,28(3):307-329
Scotland’s future within the European Union (EU) played a prominent role in the 2014 independence referendum. The story goes that latent supporters of independence voted to stay within the UK to maintain EU access. Defeated, Scottish leaders declared the referendum a once-in-a-life-time event only repeated if conditions substantially changed. With the UK now facing a chaotic exit from the EU, proponents of Scottish independence have suggested that a second referendum may occur after Brexit negotiations are completed. Faced with a consensus among Scottish party leaders in supporting EU membership, those hoping for a second independence referendum, we argue, looked to alternate sources of information that saw Brexit as an opportunity to create the conditions that would spur a second referendum. Using panel data from the British Election Study, we examine whether Scottish voters voted tactically to leave the EU. We argue that Scottish National Party voters were likely to interpret statements on the conditions for a second independence referendum as an implicit signal to vote “Leave.” The results have important implications for the role of referendums in representative democracy, strategic voting, and the importance of intra-party division on individual vote choices. 相似文献
127.
Marcia M. Croft Maria I. Marshall Martins Odendo Christine Ndinya Naman N. Ondego Pamela Obura 《发展研究杂志》2018,54(4):758-775
Indigenous vegetables play an important role in Kenyan food security, but production is limited by poor seed quality. Traditionally, seeds have been traded through informal networks, but a new formal seed sector is emerging. This study assessed the relative potential for formal or informal seed systems to meet the need for high-quality indigenous vegetable seed. By evaluating determinants of farmers’ seed purchasing behaviour, we conclude that informal seed systems have greater potential to meet this need and should be strengthened. This study suggests that policy-makers should use context-specific data to guide decisions on seed policy. 相似文献
128.
Correlates of Childhood vs. Adolescence Internalizing Symptomatology from Infancy to Young Adulthood
John D. Haltigan Glenn I. Roisman Elizabeth Cauffman Cathryn Booth-LaForce 《Journal of youth and adolescence》2017,46(1):197-212
In light of its associations with child and adolescent health and well-being, there remains a need to better understand the etiological underpinnings and developmental course of internalizing symptomatology in children and adolescents. This study leveraged intensive longitudinal data (N?=?959; 49.6?% females) to test the hypothesis that internalizing symptoms in childhood may be driven more strongly by family experiences whereas internalizing symptoms in adolescence may derive more uniquely from familial loading for affective disorders (i.e., maternal depression). We evaluated the relative contributions of (a) family experiences (b) maternal depression, and (c) peer influences in testing this hypothesis. The results indicated that family predictors were more strongly correlated with childhood (relative to adolescent) internalizing symptoms. In contrast to previous findings, maternal depression also exhibited stronger associations with childhood internalizing symptoms. Although often overlooked in theories concerning potential differential origins of childhood vs. adolescent internalizing symptomatology, peer experiences explained unique variation in both childhood and adolescent internalizing problems. 相似文献
129.
Since the mid-twentieth century, elite political behavior in the United States has become much more nationalized. In Congress, for example, within-party geographic cleavages have declined, roll-call voting has become more one-dimensional, and Democrats and Republicans have diverged along this main dimension of national partisan conflict. The existing literature finds that citizens have only weakly and belatedly mimicked elite trends. We show, however, that a different picture emerges if we focus not on individual citizens, but on the aggregate characteristics of geographic constituencies. Using biennial estimates of the economic, racial, and social policy liberalism of the average Democrat and Republican in each state over the past six decades, we demonstrate a surprisingly close correspondence between mass and elite trends. Specifically, we find that: (1) ideological divergence between Democrats and Republicans has widened dramatically within each domain, just as it has in Congress; (2) ideological variation across senators’ partisan subconstituencies is now explained almost completely by party rather than state, closely tracking trends in the Senate; and (3) economic, racial, and social liberalism have become highly correlated across partisan subconstituencies, just as they have across members of Congress. Overall, our findings contradict the reigning consensus that polarization in Congress has proceeded much more rapidly and extensively than polarization in the mass public. 相似文献
130.
Christopher Courtheyn 《The Journal of peasant studies》2013,40(7):1432-1459
ABSTRACTScholars are increasingly re-theorizing territory beyond the nation-state given Indigenous and Afro-descendant groups’ demands for ‘territory’ as they confront land grabbing in Latin America. Yet alternative territorialities are not limited to such ethnic groups. Based on 16 months of ethnographic research between 2011 and 2016, I explore the relational territoriality produced by a peasant ‘peace community’ in San José de Apartadó, Colombia. By tracing the collective political subject produced by the Peace Community’s active production of peace through a set of spatial practices, places and values, which include massacre commemorations, food sovereignty initiatives and Indigenous–peasant solidarity networks, this contribution presents a conceptual framework for analyzing diverse territorial formations. 相似文献