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971.
972.
The findings of a questionnaire survey of sexual attitudes and behavior of a large nationwide sample of Israeli adolescents (N=5410) show clear gender differences in patterns of sexual behavior even among kibbutz adolescents who express very permissive attitudes toward premarital coitus and live under conditions which provide easy access to potential sexual partners. Permissive conditions increase rates of coitus among female adolescents, but this sexual experience occurs within the framework of an emotionally involving relationship. Kibbutz girls who report coital rates equal to those of kibbutz and nonkibbutz boys (about 40%) have their first coital relationship with a steady boyfriend with whom they are in love and continue having sexual relations with the same partner. This pattern is similar to that of nonkibbutz females, who report much lower rates of coitus (14%). Males do not necessarily have sexual relations in the context of an emotional relationship. The findings are interpreted in terms of pattern of sex-role socialization.This study was supported by the Israel Center for Demographic Studies and by the Ministry of Health.Research interests are socialization, parent-child interaction, and cross-cultural research.Presently working on Ph.D. in public health at University of California, Berkeley.Research interests are child development and personality.Research interests are clinical obstetrics and gynecology, contraception, sex education, and family planning.Research interests are chronic disease epidemiology and research methodology.  相似文献   
973.
A 9-locus microsatellite framework (minimal haplotype), previously developed for forensic purposes so as to facilitate stain analysis, personal identification and kinship testing, has been adopted for the establishment of a large reference database of male European Y-chromosomal haplotypes. The extent of population stratification pertaining to this database, an issue crucial for its practical forensic application, was assessed through analysis of molecular variance (AMOVA) of the 20 regional samples included. Despite the notion of some significant haplotype frequency differences, which were found to correlate with known demographic and historic features of Europeans, AMOVA generally revealed a high level of genetic homogeneity among the populations analyzed. Owing to their high diversity, however, accurate frequency estimation is difficult for Y-STR haplotypes when realistic (i.e. moderately sized) datasets are being used. As expected, strong pair-wise and higher order allelic associations were found to exist between all markers studied, implying that haplotype frequencies cannot be estimated as products of allele frequencies. A new extrapolation method was therefore developed which treats haplotype frequencies as random variables and generates estimates of the underlying distribution functions on the basis of closely related haplotypes. This approach, termed frequency 'surveying', is based upon standard population genetics theory and can in principle be applied to any combination of markers located on the Y-chromosome or in the mitochondrial genome. Application of the method to the quality assured reference Y-STR haplotype database described herein will prove very useful for the evaluation of positive trace-donor matches in forensic casework.  相似文献   
974.
An analysis is given of Kantorovich's method of resolving multipliers. It is shown that the method is equivalent to a parametric method but that it is also equivalent with the simplex method with a special rule for the choice of the new basic variable.  相似文献   
975.
Child neglect, the failure to adequately meet a youngster's care needs, is the most frequent form of child maltreatment reported to welfare authorities. However, there have been few empirical reports of treatment outcomes for adjudicated, child neglectful parents. In the current study, an initial assessment of three neglectful parents revealed substantial deficits in cognitive problem-solving skills related to child care judgment. Treatment, consisting of modeling, shaping, practice, and feedback was used to improve each parent's child care problem-solving skills in a multiple baseline design. Skill enhancement was also found for untrained (generalization) problem situations, and independent caseworker ratings of each family's functioning provided external validation of the intervention's clinical impact.  相似文献   
976.
977.
A substantial minority (35%) of the Dutch population is in favor of capital punishment. In this paper, it is argued that in a staunchly abolitionist country such as The Netherlands, the existence and perseverance of such support can be better understood and explained by conceiving of capital punishment support in attitudinal terms as part of a law and order syndrome. Death penalty attitudes are analyzed by means of hierarchic logistic regression analysis. It is shown that support can be modeled quite well, partly in terms of general attitudes to criminal justice, partly in terms of political and sociodemographic parameters. Within the criminal justice attitudes complex, more support is found among those endorsing harsh treatment of offenders, those willing to grant far-reaching powers to justice authorities, those believing that the government is not delivering on the topic of crime fighting, and those who are concerned about the level of crime. Within the political context, more support is enlisted among people who abstain from voting and those who vote at either extreme of the political spectrum as opposed to central parties' supporters. In sociodemographic segments it is the younger and poorly educated who are the strongest supporters of capital punishment. It is suggested that endorsing capital punishment can be better understood as an expressive act, displaying dissatisfaction with judicial and political elites in the country.  相似文献   
978.
979.
We report the results of Spanish and Portuguese working group (GEP) of International Society of Forensic Genetics (ISFG) Collaborative Exercise 2001-2002 on mitochondrial DNA (mtDNA) analysis. 64 laboratories from Spain, Portugal and several Latin-American countries participated in this quality control exercise. Five samples were sent to the participating laboratories, four blood stains (M1-M4) and a sample (M5) consisting of two hair shaft fragments. M4 was non-human (Felis catus) in origin; therefore, the capacity of the labs to identify the biological source of this sample was an integral part of the exercise. Some labs detected the non-human origin of M4 by carrying out immuno-diffussion techniques using antihuman serum, whereas others identified the specific animal origin by testing the sample against a set of animal antibodies or by means of the analysis of mtDNA regions (Cyt-b, 12S, and 16S genes). The results of the other three human blood stains (M1-M3) improved in relation to the last Collaborative Exercises but those related to hairs yielded a low rate of success which clearly contrasts with previous results. As a consequence of this, some labs performed additional analysis showing that the origin of this low efficiency was not the presence of inhibitors, but the low quantity of DNA present in these specific hair samples and the degradation.As a general conclusion the results emphasize the need of external proficiency testing as part of the accreditation procedure for the labs performing mtDNA analysis in forensic casework.  相似文献   
980.
Human mitochondrial DNA from 50 trios consisting of mother (M), child (C) and father (F) was PCR amplified with primers flanking the hyper-variable regions, HVR1 and HVR2. The amplified products were then fractionated under non-denaturing conditions, silver-stained and compared by single-stranded conformational polymorphism (SSCP). In all but one case, mother and child displayed identical patterns, which could be promptly distinguished from that of the father. For the remaining cases, either set of primers was sufficient to resolve the familial ties. In no instance, M displayed alleles different from those of C within each trio, demonstrating that no false exclusions occurred. The SSCP approach proved to be a robust technique suitable as a preliminary screening in cases requiring identification of multiple samples.  相似文献   
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