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921.
Mitochondrial DNA regions HVI and HVII population data. 总被引:2,自引:0,他引:2
B Budowle M R Wilson J A DiZinno C Stauffer M A Fasano M M Holland K L Monson 《Forensic science international》1999,103(1):23-35
Data from 1393 unrelated individuals have been compiled from eight population groups: African Americans, Africans (Sierra Leone), U.S. Caucasians, Austrians, French, Hispanics, Japanese, and Asian Americans. The majority of the mtDNA sequences were observed only once within each population group (i.e., ranging from a low of 60.3% (35/58) of the Asian American sequences to a high of 85.3% (93/109) of the French sequences). Genetic diversity ranged from 0.990 in the African sample to 0.998 in African Americans. Random match probability ranged from 2.50% in the Asian American sample to 0.52% in U.S. Caucasians. The average number of nucleotide differences between individuals in a database is greatest for the African American and African samples (14.1 and 13.1, respectively), and the least variable are the Caucasians (ranging from 7.2 to 8.4). Substitutions are the predominate polymorphism, and at least 92% of the substitutions are transitions. The most prevalent transversions are As substituted for Cs and Cs substituted for As. For most population groups these transversions occurred predominately in the HVI region; however, the African, African American, and Hispanic samples also demonstrated a large portion of their C to A and A to C transversions in the HVII region (at sites 186 and/or 189). Most insertions occur in the HVII region at sites 309.1 and 315.1, within a stretch of C's. Insertions of an additional C are common in all population groups. The sequence data were converted to SSO mtDNA types and compared with population data on Caucasians, Africans, Asians, Japanese, and Mexicans described by Stoneking et al. [M. Stoneking, D. Hedgecock, R.G. Higuchi, L. Vigilant, H.A. Erlich, Population variation of human mtDNA control region sequences detected by enzymatic amplification and sequence-specific oligonucleotide probes, Am. J. Hum. Genet. 48 (1991) 370-382] using an R x C contingency table test. Differences between major population groups (i.e., between African, Caucasian, and Asian) are quite evident, and similar ethnic population groups carried similar SSO polymorphism frequencies. There were only a few SSO types that showed significant differences between subpopulation groups. The SSO data alone can not be used to describe the population genetics with complete sequence data. However, the results of the SSO comparisons are similar to other analyses, and differences in sequence data in regions HVI and HVII are greater between major population groups than between subgroups. 相似文献
922.
R. J. Mourits N. van den Berg M. Rodríguez-Girondo K. Mandemakers P. E. Slagboom M. Beekman 《The History of the Family》2020,25(3):484-526
ABSTRACT Studies have shown that long-lived individuals seem to pass their survival advantage on to their offspring. Offspring of long-lived parents had a lifelong survival advantage over individuals without long-lived parents, making them more likely to become long-lived themselves. We test whether the survival advantage enjoyed by offspring of long-lived individuals is explained by environmental factors. 101,577 individuals from 16,905 families in the 1812–1886 Zeeland cohort were followed over time. To prevent that certain families were overrepresented in our data, disjoint family trees were selected. Offspring was included if the age at death of both parents was known. Our analyses show that multiple familial resources are associated with survival within the first 5 years of life, with stronger maternal than paternal effects. However, between ages 5 and 100 both parents contribute equally to offspring’s survival chances. After age 5, offspring of long-lived fathers and long-lived mothers had a 16-19% lower chance of dying at any given point in time than individuals without long-lived parents. This survival advantage is most likely genetic in nature, as it could not be explained by other, tested familial resources and is transmitted equally by fathers and mothers. 相似文献
923.
AbstractThis article reports on timing the adverse effects of black carbon released into the atmosphere from biomass combustion, vehicular emissions and local combustion sources. Black carbon contributes to global warming through its light absorption capacity, has a direct and indirect impact on climate and public health, and will result in ongoing environmental damages and claims. The authors studied measurements of black carbon taken in Delhi, India during 2016 and 2017, and reports on seasonal factors that contribute to higher emissions. 相似文献
924.
Kristopher D. Wisniewski Ph.D. Nicholas Cooper M.Sc. Vivienne Heaton Ph.D. Colin Hope B.Sc.; M.Sc. Duncan Pirrie Ph.D. Andrew J. Mitten M.Geo. Jamie K. Pringle Ph.D. 《Journal of forensic sciences》2019,64(5):1530-1539
Police witness intelligence stated a murdered adult male “Fred” had been vertically buried in wooded hilly terrain 30 years ago in the Midlands, U.K. Conventional search methods were unsuccessful; therefore, the police requested a geophysical investigation to be undertaken to determine whether “Fred” could be detected. A multiphased geophysical approach was conducted, using bulk ground conductivity and metal detectors, then follow‐up magnetics and ground penetrating radar (GPR) survey profiles on electromagnetic (EM) anomalous areas. A tight grid pattern was used to account for the reduced target size. Relatively high‐resolution EM and GPR techniques were determined optimal for this terrain and sandy soil. Geophysical anomalies were identified and the most promising intrusively investigated, and this was found to be a large boulder and tree roots. Study implications suggest careful multiphase geophysical surveys are best practice and give confidence in cold case searches. This study yielded a no‐body result, effectively saving police time and costs from further investigations. 相似文献
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926.
Christina Mancini Amy K. Cook Jessica C. Smith Robyn McDougle 《Journal of school violence》2020,19(4):610-622
ABSTRACT Recently, states have enacted teacher-carry laws. While controversial, little scholarship has tapped public attitudes toward such reforms. Because public opinion shapes policy, the public is an important stakeholder in this debate. Thus, we investigated three questions. First, how supportive is the public of arming teachers? Second, what demographic and social divides exist, if any, for reform approval? Finally, do crime-related perceptions, concerning views about public safety, and criminogenic influences shape policy preferences? We test these questions using a 2018 poll of Virginia residents (N = 521). Overall, approval for teacher-carry is split. Crime-related perceptions mediate some of the initial social and demographic divides in opinion but other correlates, such as parental status, remain salient predictors of views. Implications are discussed. 相似文献
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930.
Andreas Boes Tobias Kämpf Thomas Lühr Alexander Ziegler 《Berliner Journal für Soziologie》2018,28(1-2):181-208
There has been a long-standing discussion since the 1980s about the question whether new production models harbor a potential for extended employee participation and involvement, in most cases with disillusioning results. This paper is concerned with so called “agile methods”, which play an important part in the area of knowledge work in the course of the digital transformation. On the basis of two case studies from software development and industrial R&D, the paper examines the concrete implementation of these methods and the employees’ perspective upon them and their consequences. The result is that agile methods present a potential for extended employee participation and involvement; however, the realization of this potential depends on the concrete way how the agile concept of “empowerment” is implemented. 相似文献