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1.
The optical and morphological properties of resveratrol were investigated. This nontoxic fluorescent natural material, emitting in the visible blue light, was used as an optical marker, enabling the enhancement of the image contrast coming from relief pictures marked on challenging surfaces. By applying appropriated imaging softwares, this marker was verified to be very useful in the latent fingerprint recognition deposited on different wood surface types, mainly those with high level of roughness, where conventional forensic materials do not allow effective fingerprint image visualization.  相似文献   
2.
Among the major transformations affecting Mexican women in recent decades were their growing participation in the labor market and the fertility decline that began in the 1970s with widespread access to contraception. Data from 3 major Mexican fertility surveys, employment surveys, and censuses are used to analyze changes in female employment and their determinants during the years of economic recession in the 1980s. The main characteristics of the Mexican fertility decline are described, and the relationship between fertility and female employment before and during the economic recession is scrutinized for different social sectors. Suggestions for research on the affects of these changes on the social condition of Mexican women are then presented. The proportions of Mexican women over 12 years old who declared themselves economically active increased from 16% in 1970 to 21% in 1979 and 32% in 1987. Until the 1970s the majority of employed women were young and single or childless. But a clear increase occurred between 1976-87 in the economic participation of older women in union. Economic participation of low income and less educated women increased as they sought work or created their own in response to deteriorating living conditions during the recession. Young women with intermediate or higher educational levels did not increase their relative presence in the labor market in the same period. The marked increase in economic participation of less educated women in union with small children was accompanied by a significant increase in manual occupations. Between 1982-87, the proportion of women aged 20-49 in nonsalaried manual occupations rose from 7.6% to 18.5%. Mexico's fertility decline has been well documented. The total fertility rate declined from 6.3 in 1973 to 3.8 in 1986, while the percentage of women in union using a contraceptive method increased from 30.2 in 1976 to 52.7 in 1987. Fertility differentials have been declining but are still considerable. The inhibitory influence of children on female labor force participation in Mexico is clear, but in the years of economic recession the most notable increase in female workers was in women with 3 or more children of whom the youngest was under 3. It appears that the influence of children on women's employment depends on the socioeconomic status of the woman as well as on the dynamism or sluggishness of the labor market. Research is needed on the significance of changes in fertility and female employment for women's status in Mexico. Several recent works have presented results of microsocial analyses of the ways in which women experience changes in their lives resulting from fertility and employment decisions. A methodological strategy for studying these changes and their influence on women's status should focus on comparisons between different generations and birth cohorts, different types of employment, and different socioeconomic statuses. Both macrosocial and microsocial forms of analysis are needed to provide a full picture.  相似文献   
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A clear positive case for anabolic steroids doping was confounded by alleged urine tampering during doping control procedures. Review of the chain of custody showed no flaws, but nevertheless the athlete was adamant that the urine sample should be analyzed for DNA in order to support her contention that she was not the donor of the sample. The results obtained showed that the urine sample that scored positive for steroids contained nuclear DNA that could not be matched to the DNA obtained from the athlete's blood. On the other hand, the same urine sample contained mitochondrial DNA whose nucleotide sequences spanning the hyper variable regions HV1 and HV2 proved to be identical to those determined in mitochondrial DNA amplified from the athlete's blood. The occurrence of an extraneous genotype is compatible with exogenous nuclear DNA admixture to the athlete's urine. Alternatively, taking in consideration the mitochondrial DNA, we could not exclude that a sibling or a maternal relative of the athlete could have acted as a donor of the urine utilized for doping control and DNA analysis. Both situations point to possible tampering of the urine by the athlete. Adjudication at CAS maintained previous national and international federation decision that there was no proof of a chain of custody flaw to justify the athlete's allegation of urine substitution after collection.  相似文献   
5.
In patrilineal societies, surnames and Y-specific haplotypes and haplogroups are expected to be correlated. This characteristic could help defining an initial pool of suspects in forensic genetics analysis. Here we evaluated this correlation in a sample of Central-Brazilian men. Surnames and Y-SNP haplogroup and Y-STR haplotype were analyzed in 55 pairs of Central-Brazilian men sharing surnames (n = 110). Seven haplogroups and thirty-two haplotypes have been observed, none correlated solely to any of the twenty-eight surnames represented here. In this sample, two men with the same surname showed a chance of 0.41 of sharing a Y-specific haplogroup. This chance is higher for surnames of intermediate frequencies, whereas rare surnames show distinct chances as zero and one. Observed results may be over-estimated due to a predominance of a specific haplogroup (P92R7 = 49%) in the sample, what makes it possible for two men with no coancestry to share this haplogroup. Considering STR, only three pairs of men shared haplotypes. The average difference between the haplotypes in each pair was 2.45 mutational steps. This relatively low correlation is due to some historical and cultural peculiarities of the country, what makes it improper for forensic purposes in Brazil.  相似文献   
6.
The authors evaluate the consequences of incomplete necroscopic examinations wherein it was impossible to apply radiological resources to locate firearm projectiles. The study includes 8185 reports from the Instituto Médico-Legal Afranio Peixoto in Rio de Janeiro, Brazil, representing the totality of corpses processed from January to December 2001; of these, 3122 were gunshot victims, 309 of which were buried with unremoved projectiles, being liable to future judicial reappraisal. During the same period, there were 23 exhumation requests by police authorities, 12 of them querying the existence of projectiles. The authors looked into the formal reasons assumed by the medico legal experts to conclude their reports from incomplete examinations, and suggest that gunshot necroscopic examinations should follow specific protocols, as incomplete autopsies will require further exhumations, at unnecessary additional costs.  相似文献   
7.
DNA is one of the fastest growing tools in forensic sciences, increasing reliability in forensic reports and judgments. The use of DNA has increased in different areas of the forensic sciences, such as investigation of plant species, where plastid DNA has been used to elucidate and generate evidence in cases of traceability of genetically modified and controlled plants. Even with several advances and the practice of using DNA in forensic investigations, there are just few studies related to the identification of genetic tools for the characterization of drug and nondrug-types of Cannabis. Herein, the whole plastomes of two drug-type Cannabis are presented and have their structures compared with other Cannabis plastomes deposited in the GenBank, focusing in the forensic use of plastome sequences. The plastomes of Cannabis sativa “Brazuka” and of the hybrid Cannabis AK Royal Automatic presented general structure that does not differs from the reported for other C. sativa cultivars. A phylogenomic analyses grouped C. sativa “Brazuka” with the nondrug C. sativa cultivars, while the hybrid Cannabis AK Royal Automatic placed isolated, basal to this group. This suggests that the analysis of plastomes is useful toward genetic identification of hybrids in relation to C. sativa.  相似文献   
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The secondary dentin deposition that occurs after the tooth formation process results in a decrease in pulp cavity volume in adolescents and adults. The purpose of this critical review was to correlate pulpal and/or dental volume on cone-beam computed tomography (CBCT) with chronological age approximation. A subobjective was to investigate which methodology and CBCT technical parameters would be most appropriate to evaluate this correlation. This critical review followed the PRISMA guidelines, and it was conducted by a search through PubMed, Embase, SciELO, Scopus, Web of Science, Cochrane Library databases, as well as gray literature. Primary studies that used pulp volume, or pulp chamber to tooth volume ratio measured using CBCT were included. Seven hundred and eight indexed and 31 non-indexed records were identified. A qualitative analysis was performed including 25 selected studies with a total of 5100 individuals, age ranging from 8 to 87 years without sex predilection. The most used method was pulp volume/tooth volume. CBCT voxel size ranged between 0.09 and 0.5. Manual segmentation associated with threshold algorithms was used in most of the studies. Correlation between the pulp volume/tooth volume ratio was moderate: −0.66 for the upper central incisors, −0.59 for upper canines and −0.56 for lower canines. High heterogeneity was observed among the studies. It is concluded that pulp volume should be used with caution in age estimation. Evidence supports the preferable use of upper incisors with pulp volume/tooth volume ratio for age estimation. There is not enough evidence that voxel size interferes in age estimation by pulp volume.  相似文献   
10.
This article assesses the European Union (EU)’s engagement with the Israeli-Palestinian conflict and highlights the unintended consequences of the policies pursued by Brussels on this matter. While stressing that Palestinians and Israelis interested in peace face the danger of the banalization of the conflict, the article argues that the current status quo is unacceptable and unstainable in the long run, and this demands new policies from the actors involved with the conflict or its resolution. The EU policies’ overall rationale must be to treat the Israeli?Palestinian dispute as a normal, non-exceptional conflict, in which economic and legal tools can be employed to create new legal facts on the ground. An alternative EU approach to the conflict must recognize the insufficiency of recent initiatives and should be built upon two pillars: the legalization of the main contending issues and the empowerment of the civil society actors and initiatives that foster dialogue between Palestinians and Israelis.  相似文献   
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