Selenium determination in mother and child's hair by electrothermal atomic absorption spectrometry

A method for the selenium determination in a mother and her child's hair using palladium as a chemical modifier was optimized. The sample was digested with nitric acid and hydrogen peroxide and diluted to 5 ml. To achieve complete mineralization the samples were ashed at 1200 degrees C in the presence of palladium as a chemical modifier. The optimum atomization temperature was 1900 degrees C. The precision and accuracy of the method were studied using the reference material CRM 397. Results of calibration using aqueous standards and the standard addition method were compared. The method was applied to the selenium determination in 30 samples of the mother's and child's hair. The levels found were 0.54 +/- 0.34 microgram/g for mother's hair and 0.77 +/- 0.25 microgram/g for child's hair.     

Striking hard rock veins. Multinational Corporations and Miners’ Unions in Mexico and the United States, 1906-1952

ABSTRACT

This paper analyzes simultaneous strikes during the first half of the 20th century in North America. The transformation of production in copper, lead, zinc, and silver mining districts determined the formation of a working class that operated between Mexico and the United States. Therefore, the labor conflicts combined market circumstances and management-imposed homologation of work structures across firm divisions with the international coordination of miners. The paper describes the emergence, growth, and demise of a regional industrial system.     

Sport,Gender and Ethnicity: Practises of Symbolic Inclusion/Exclusion

In this paper symbolic inclusion/exclusion processes in sport with respect to gender and ethnicity among adolescents (n = 1025) are analyzed from a social-critical perspective. It was found that sport participation preferences of young people are still influenced by dominant normative gendered and racial/ethnic images. Sport can serve not only as an agent of integration among youth, but is also used to differentiate and discriminate. On one hand sport participation is less predictable with respect to gender, due for example to interactions with ethnicity. Although ethnic minority girls participate the least in sport, ‘black,’ traditional ‘masculine‘ sports such as soccer and fighting/self-defense are valued relative highly. On the other hand, the data show that especially the male adolescents symbolically exclude girls from ‘masculine’ sports such as soccer; in addition for both ethnic minority and majority boys the fear of being labelled as a ‘sissy’ works as a strong mechanism of self-exclusion from participation in traditional ‘feminine’ sports. However, stereotypical normative images are not only confirmed through sport (participation), but also continually challenged.Researcher/lecturer, Tilburg University. Research interest in inclusionary and exclusionary mechanisms in sport, especially with respect to gender, ethnicity and sexuality.Senior researcher, Utrecht University. Major research interest in gender, ethnicity and leadership positions in sport.     

Genetic variability of 16 Y-chromosome STRs in a sample from Equatorial Guinea (Central Africa)

Nine Y-STR loci from the "minimal haplotype" included in Y-STR Haplotype Reference Databases (YHRD) together with eight additional Y-STRs (DYS437, DYS438, DYS439, DYS460, DYS461, GATA C4, GATA H4 and GATA A10) were analyzed in a sample of 101 males from Equatorial Guinea living in Madrid. Haplotype and allelic frequencies were calculated and genetic diversities were estimated for each genetic system as well as for the whole haplotype. An unexpected high frequency (6%) of intermediate alleles (13.2 and 14.2) was found in DYS385. For DYS19, two alleles were found in one sample. Another sample failed to amplify with DYS393 primers using either PowerPlex Y System (Promega Corporation) or the Y-PLEXtrade mark 12 (Reliagene, New Orleans, LA) commercial kits. Comparison between Equatorial Guinea and another African population (Mozambique; South East Coast) revealed a significant pairwise Phi(st) value between them (Phi(st)=0.03309; P=0.00000).     

STR analysis of artificially degraded DNA-results of a collaborative European exercise

Degradation of human DNA extracted from forensic stains is, in most cases, the result of a natural process due to the exposure of the stain samples to the environment. Experiences with degraded DNA from casework samples show that every sample may exhibit different properties in this respect, and that it is difficult to systematically assess the performance of routinely used typing systems for the analysis of degraded DNA samples. Using a batch of artificially degraded DNA with an average fragment size of approx. 200 bp a collaborative exercise was carried out among 38 forensic laboratories from 17 European countries. The results were assessed according to correct allele detection, peak height and balance as well as the occurrence of artefacts. A number of common problems were identified based on these results such as strong peak imbalance in heterozygous genotypes for the larger short tandem repeat (STR) fragments after increased PCR cycle numbers, artefact signals and allelic drop-out. Based on the observations, strategies are discussed to overcome these problems. The strategies include careful balancing of the amount of template DNA and the PCR cycle numbers, the reaction volume and the amount of Taq polymerase. Furthermore, a careful evaluation of the results of the fragment analysis and of automated allele calling is necessary to identify the correct alleles and avoid artefacts.     

Social perception of rape: how rape myth acceptance modulates the influence of situational factors

This study assessed the role of rape myth acceptance (RMA) and situational factors in the perception of three different rape scenarios (date rape, marital rape, and stranger rape). One hundred and eighty-two psychology undergraduates were asked to emit four judgements about each rape situation: victim responsibility, perpetrator responsibility, intensity of trauma, and likelihood to report the crime to the police. It was hypothesized that neither RMA nor situational factors alone can explain how rape is perceived; it is the interaction between these two factors that best account for social reactions to sexual aggression. The results generally supported the authors' hypothesis: Victim blame, estimation of trauma, and the likelihood of reporting the crime to the police were best explained by the interaction between observer characteristics, such as RMA, and situational clues. That is, the less stereotypic the rape situation was, the greater was the influence of attitudes toward rape on attributions.     

Eight short tandem repeats (STR) frequencies for descendants from Terena indigenous Brazilian group

POPULATION: descendants from Terenas an indigenous group.     

Postmortem citalopram concentrations: alone or along with other compounds

Citalopram, an antidepressant whose use has become more widespread in Spain in recent years participates directly and indirectly in the lethal mechanism in voluntary and involuntary poisonings. There were 30 cases of autopsies in the Madrid region where citalopram and other psychoactive substances (psychotropic drugs, alcohol, opiates) were detected in the corpses. The postmortem citalopram levels in relation to the manner and mechanism of death were evaluated, and a significant difference between the toxic and nontoxic cases (p < 0.01) was found. We studied the citalopram blood levels alone and along with other psychoactive products, and these cases were then further divided into those where the compounds were at deadly levels and those which were not. We found a range of citalopram levels between 0.37 and 0.83 microg/mL in which some cases were associated with citalopram toxicity and others were not. Citalopram blood levels of less than 0.35 microg/mL did not lead to fatal poisoning when it was the sole substance detected.