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Two Native American populations from North and northwest regions of Argentina (Toba and Colla) were analyzed for 17 Y chromosome short tandem repeat loci (Y-STRs), namely, DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635 and GATA H4.1. Over 357 allele transfers, two one-step mutations could be detected at DYS456 and GATA H4.1 loci. A new 16.1 ‘micro-variant’ allele was observed for DYS385, characterized by an insertion at the fifth GAAA repeat. We also observed two alleles at the DYS448 locus in three samples (two from Toba and one from Colla). A total of 34 and 16 different haplotypes were detected for Toba and Colla, respectively, the former with a haplotype diversity value of 0.9769 ± 0.01, whereas 0.9497 ± 0.02 for the latter. Significant population differences were observed between Colla and Toba, at least in part, due to a more prevalent European input in the Colla. In agreement with this observation is the fact that the genetic distances between Colla and Iberian populations are lower than those observed between Iberian and any other Native American population. The results of multiscaling dimensional analysis and genetic distances (Rst) among Native American population samples also reflect this fact. The data show the existence of clear population stratification in the Argentina, a fact that should be taken into account in forensic casework.  相似文献   
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The characterisation and comparison of pencil markings on paper is an area of questioned document analysis that has previously not received much attention. Despite this, there would be value in an examiner being able to analyse two pencil markings and coming to a conclusion about whether they were from a similar or different source. Previous studies have analysed raw materials and bulk pencil cores for purposes of characterisation and differentiation, but to date, no studies have successfully analysed pencil markings non-destructively off a paper substrate. In this work, pencils from a number of manufacturers were analysed by inductively coupled plasma mass spectrometry (ICP-MS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). Analysis of data using multivariate techniques (principal component analysis), showed that ToF-SIMS can successfully be used to analyse such pencil markings to deduce whether two markings can be differentiated, in terms of inorganic elemental composition. It was possible to discriminate between pencil markings from different manufacturers, and it was also indicated that pencils from the same manufacturer, but discrete batches, can be significantly different.  相似文献   
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Research on attitudinal differences between female and male police officers has burgeoned since the 1980s, producing a rich albeit at times contradictory legacy. Focusing on quantitative studies published after 1990, this current study reviewed empirical results regarding attitudinal differences between female and male police officers. A comprehensive search of the literature yielded thirty-three articles where gender was used either as an independent or control variable in multivariate regression analysis. A general finding was that officer gender has only a weak effect on officers' attitudes toward community policing, the community and neighborhood residents, job satisfaction, and domestic violence. There was some limited evidence showing that male and female officers differ in their attitudes toward the police role and stress. The limitations of this research are pointed out, and the directions for future research are identified.  相似文献   
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The Uncovered Set and the Limits of Legislative Action   总被引:1,自引:0,他引:1  
Ivan Jeliazkov Department of Economics, University of California, Irvine,Irvine, CA Itai Sened Department of Political Science, Washington University in St. Louis, St. Louis, MO We present a simulation technique for sorting out the size,shape, and location of the uncovered set to estimate the setof enactable outcomes in "real-world" social choice situations,such as the contemporary Congress. The uncovered set is a well-knownbut underexploited solution concept in the literature on spatialvoting games and collective choice mechanisms. We explain thissolution concept in nontechnical terms, submit some theoreticalobservations to improve our theoretical grasp of it, and providea simulation technique that makes it possible to estimate thisset and thus enable a series of tests of its empirical relevance.  相似文献   
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The present paper investigates the risk of lifetime suicide ideation associated with problem-solving ability and attitudes toward suicidal behavior in a sample of 328 university students (41% male, 59% female). The response rate was 77% based on the total number of students registered for the relevant courses. A series of questions assessed lifetime suicide ideation, while problem solving and attitudes toward suicide were measured using the Self-Rating Problem Solving scale and four subscales of the Suicide Opinion Questionnaire, respectively (McLeavey, 1986; Domino et al., 1989). Almost one-third of the students surveyed had lifetime suicide ideation. Both genders were similar in terms of their suicide ideation history, problem solving, and attitudes toward suicidal behavior with the exception that male students were more in agreement with the attitude that suicidal behavior lacks real intent. Compared with 2% of nonideators and ideators, one in four planners reported that they would more than likely attempt suicide at some point in their life. Greater agreement with the attitude that suicidal behavior is normal was associated with significantly increased risk of being an ideator, as was poor problem solving and less agreement with the attitude that suicidal behavior is associated with mental illness.  相似文献   
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Business incubators have become a popular policy option and economic development intervention tool. However, recent research shows that incubated firms may not benefit significantly from their incubator relationships, and may even be more vulnerable to failure post departure (graduation) from an incubator. These findings suggest that the impact of business incubation on new venture viability may be contingent on the type of support offered by an incubator and attributes of business environments within which incubation services are provided. Incubation services that protect and isolate ventures from key resource dependencies may hinder venture development and increase subsequent vulnerability to environmental demands. Alternatively, incubation services that help ventures connect and align with key resource dependencies are likely to promote firm survival. We propose that incubators vary in the services and resources they offer, and that university incubators typically provide greater connectivity and legitimacy with respect to important contingencies associated with key industry and community stakeholders. This leads us to propose that university affiliation is an important contingency that affects the relationship between firms’ participation in incubators and their subsequent performance. The purpose of this study is to evaluate this contingency by examining whether firms graduating from university incubators attain higher levels of post-incubation performance than firms participating in non-university affiliated incubators. We test this by evaluating the performance of a sample of graduated firms associated with the population of university-based incubators in the US contrasted against the performance of a matched cohort of non-incubated firms. The analysis uses an enhanced dataset that tracks the number of employees, sales, and the entry and graduation (departure) points of incubated firms from a university incubation program, so as to delineate the scope of influence of the incubator.  相似文献   
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