Development of Friendship and Task Values in a New School: Friend Selection for the Arts and Physical Education but Socialization for Academic Subjects

Friends provide important social contexts for student development. Research has shown that adolescent friends are similar to each other in their interest and values for different school subjects. Yet our current understanding does not extend to knowing whether selection, deselection, or socialization processes are responsible for this phenomena. Without this knowledge, it is very difficult for parents, teachers, and schools to know how and when to intervene. This study investigated selection, deselection, and socialization effects on adolescent students’ task values for academic (languages, math and science, and social sciences) and non-academic subject areas (the arts and physical education). A social network approach was used to examine two waves of annual data collected from school-based networks of adolescents in the first and second years of high school education in Finland (N?=?1419; female?=?48.6%; mean age at first measurement point?=?16). The results revealed that adolescents tended to select friends with similar levels of task values (friend selection) for the arts and physical education, but friends did not become more similar in these areas over time (friend socialization). In contrast, there was evidence of friend socialization, but not friend selection, for the academic school subjects. Across all subjects, differences in task values did not predict friendship dissolution (friend deselection). These findings suggest that to a significant extent, students make agentic choices in developing friendship with schoolmates based on their task values in non-academic subjects. The resultant friend contexts that individuals created, in turn, affected their task values in academic subject areas. These results shed light on the complexity of friend effect mechanisms on task values at the subject domain-specific level.     

Micro-history and the macro-models of the European demographic system in pre-industrial times: life course patterns in the Parish of Belm (Northwest Germany), seventeenth to the nineteenth centuries.

"Current models of the European demo-economic system in pre-industrial times are based on strong assumptions about the predominant patterns of individual life courses. Now recent micro-studies of individual communities make it possible to check whether the actual patterns of life fit these assumptions. The findings for Belm present an amazing blend of confirmations and contradictions. In particular, the connection between marriage and the formation of a new self-supporting household is subject to doubt. Together with the findings of other micro-studies, the evidence for Belm suggests that the assumptions about mechanisms linking marriage to economic resources should be reconsidered, and that there is need for a dialogue between macro-theories and micro-history."     

An efficient statistical procedure for interpreting DNA single locus profiling data in crime cases.

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.     

Premenstrual tension as mitigation in a criminal case.

A woman pleaded guilty to road traffic offences and was sentenced to be disqualified for holding or obtaining a driving licence for six months. Her appeal against that sentence was allowed on the basis that she was suffering from premenstrual tension at the time of the offences, and that the disqualification imposed was neither necessary nor appropriate.     

Murder in south London: a novel use of DNA profiling.

Lorraine Benson's body was found beaten and strangled at Raynes Park, Surrey, in December 1988. Considering the possibility of linked offences, a murder squad was set up to work alongside a team already investigating a rape series in the Kingston area. A man's handkerchief left at a site a quarter of a mile from the murder scene was found to be stained with blood and saliva matching that of the victim. A DNA profile was obtained from a stain of nasal mucus on this handkerchief and found to match a suspect later arrested for an attempted rape in the same locality. Also of forensic interest were dust marks made by the zips of the victim's and defendant's coats and identification of the rope used for strangulation.     

The evaluation of five electrophoretic phenotyping systems for routine screening of bloodstains

The performance of the polymorphic marker systems group-specific component (GC), phosphoglucomutase-1 (PGM), alpha-2-HS-glycoprotein (A2HS), haptoglobin (Hp), and erythrocyte acid phosphatase (EAP) was evaluated on control bloodstains. The major factors considered were: sensitivity of the test system; stability of the marker; laboratory economics of each test; and distinguishing power (Dp) of the system. GC was considered to be the most suitable marker for routine screening because of its high stability and Dp, and the sensitivity of the immunoblotting detection method. PGM and A2HS were the next most valuable markers followed by Hp. EAP could only be considered useful when large amounts of relatively fresh bloodstain were available.     

The collaborative study on typing group-specific component by eight forensic science laboratories

This report describes a collaborative study on typing group-specific component (GC), conducted between the Central Research and Support Establishment and the forensic science laboratories of England, Wales and Northern Ireland. A population study (n=114) was performed. Fifty blood donors were selected to provide a distribution, slightly biased from normal, in favour of the GC 1F-1F and GC 1F-1S phenotypes. A protocol was devised for preparing large bloodstains. The strongest GC bands were obtained from the edge of a stain after the blood had been treated with K+/EDTA. Each laboratory received a representative portion of the large bloodstains for GC typing. Five of the eight laboratories correctly grouped all the bloodstains. No errors directly attitributable to the system were recorded in over 800 tests, indicating that GC in bloodstains can be typed reliably using the combination of isoelectric focusing in ultrathin narrow pH interval gels followed by immunofixation and silver staining.     

The isolation of spermatozoa from sexual assault swabs using proteinase K

The most common examination in sexual offences is the identification of spermatozoa in aqueous extracts from swabs. Using Proteinase K with sodium dodecyl sulphate, it is possible to digest all the cellular material apart from the spermatozoa, resulting in a quick and effective method of their isolation. Spermatozoa were detected in 18 extracts using this treatment when the normal method had failed to reveal all but one of them.     

A continuous model for interpreting the positions of bands in DNA locus-specific work.

A simple but rigorous approach is offered for evaluating the evidential value of single locus DNA autoradiographs. This approach does not use a binning technique and it does not treat alleles as discrete variables. Instead, the allele distribution is considered to be continuous. The variation between two comparable bands is assessed using previously determined experimental parameters. The Bayesian treatment leads to an expression of the "quality of a match".