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151.
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
152.
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
153.
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
154.
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
155.
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
156.
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
157.
158.
AbstractWe contribute to the debate on the spatial allocation of infrastructure investments by examining where these investments generate the highest economic return (‘spatial efficiency’), and identifying trade-offs when infrastructure coverage is made more equitable across regions (‘spatial equity’). We estimate models of firm location choice in Uganda, drawing on insights from the new economic geography literature. The main findings show that manufacturing firms gain from being in areas that offer a diverse mix of economic activities. Public infrastructure investments in other locations are likely to attract fewer private investors, and will pose a spatial efficiency–equity trade-off. 相似文献
159.
160.
Susanne V. Knudsen 《Nora, Nordic Journal of Women's Studies》2013,21(2):102-112
Gender awareness and gender neutrality are discussed with the aid of post‐structuralist gender theories concerning paradoxes and aporias. Via paradox thinking, women's, men's and gender studies are challenged to develop perspectives on gender that are both thought and not thought, said and not said, done and not done. Paradoxes are understood as aporias, in which the researcher gets into “stuck places”. Gender dualism is put to the test as a fundamental concept. Various theories of power, such as patriarchy theories, theories of hegemonic power, and gender and queer‐theories of symbolic and discursive power are associated with gender paradoxes and gender dualism. Examples are included from the author's own research in school and gender studies. 相似文献