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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   
3.
This study analyzes the short‐term impact of an exogenous, positive income shock on caregivers’ subjective well‐being (SWB) in Malawi using panel data from 3,365 households targeted to receive Malawi's Social Cash Transfer Program that provides unconditional cash to ultra‐poor, labor‐constrained households. The study consists of a cluster‐randomized, longitudinal design. After the baseline survey, half of these village clusters were randomly selected to receive the transfer and a follow‐up was conducted 17 months later. We find that the short‐term impact of household income increases from the cash transfer leads to substantial SWB gains among caregivers. After a year's worth of transfers, caregivers in beneficiary households have higher life satisfaction and are more likely to believe in a better future. We examine whether program impacts on consumption, food security, resilience, and hopefulness could explain the increase in SWB but do not find that any of these mechanisms individually mediate our results.  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   
6.
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   
7.
The purpose of the present study was to examine relations between adolescents’ social cognitions regarding parenting practices and adolescents’ prosocial behavioral tendencies. A mediation model was tested whereby the degree to which adolescents perceived their parents as responding appropriately to their prosocial and antisocial behaviors was hypothesized to predict adolescents’ tendencies toward prosocial behavior indirectly by way of adolescents’ prosocial values. Adolescents (N = 140; M age = 16.76 years, SD = .80; 64% girls; 91% European Americans) completed measures of prosocial values and of the appropriateness with which they expected their parents to react to their prosocial and antisocial behaviors. In addition, teachers and parents rated the adolescents’ tendencies for prosocial behaviors. A structural equation model test showed that the degree to which adolescents expected their parents to respond appropriately to their prosocial behaviors was related positively to their prosocial values, which in turn was positively associated with their tendencies to engage in prosocial behaviors (as reported by parents and teachers). The findings provide evidence for the central role of adolescents’ evaluations and expectancies of parental behaviors and of the role of values in predicting prosocial tendencies. Discussion focuses on the implications for moral socialization theories and on the practical implications of these findings in understanding adolescents’ prosocial development.  相似文献   
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Experiences with perceived discrimination (e.g., perceptions of being treated unfairly due to race or ethnicity) are expected to impact negatively youths’ prosocial development. However, resilience often occurs in light of such experiences through cultural factors. The current longitudinal study examined the influence of perceived discrimination on the emergence of Mexican American adolescents’ later prosocial tendencies, and examined the mediating role of Mexican American values (e.g., familism, respect, and religiosity). Participants included 749 adolescents (49 % female) interviewed at 5th, 7th, and 10th grade. Results of the current study suggested that, although perceived discrimination was associated negatively with some types of prosocial tendencies (e.g., compliant, emotional, and dire) and related positively to public prosocial helping, the associations were mediated by youths’ Mexican American values. Directions for future research are presented and practical implications for promoting adolescents’ resilience are discussed.  相似文献   
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