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101.
For the first time in U.S. history, after decades of unprecedented growth in interior immigration enforcement disproportionately impacting Latinos, ten percent of the U.S. House of Representatives is Hispanic. Using congressional district-level data on all candidates participating in general elections to the U.S. House of Representatives between 2008 and 2018, we show that intensified immigration enforcement suppressed Hispanics’ representation in congressional elections. The effect—nonexistent for other minorities, such as non-Hispanic Black candidates, as well as in primary elections—is driven by local police-based measures and diminished electoral support. Furthermore, it appears more harmful during midterm elections and in localities without a sanctuary policy.  相似文献   
102.
This paper provides novel evidence on how a sharp increase in labor force participation among older women affects the provision of informal care to their older parents. Based on data from Understanding Society – The UK Household Longitudinal Study, we use an instrumental variable approach that exploits a unique reform that increased the female State Pension age by up to six years. Our results provide evidence of a trade-off between the intensive margin of work and informal care provided outside the household: an increase of 10 hours of work per week reduces the provision of informal care by 2.1 hours a week, which amounts to roughly £2,100 of yearly care-hours lost. This reduction in caregiving is largest among women working in physically or psychosocially demanding jobs, and “sandwich generation” women who have both a living grandchild and a parent alive. Using data from the English Longitudinal Study of Ageing, we show that older parents whose daughters became ineligible to claim their pensions experienced a significant reduction in the amount of care they receive from their daughters, which was not compensated by an increase in formal care or other sources of support. Our results suggest that policies that increase older workers’ labor supply require changes in long-term care policy that compensate for the loss of informal care.  相似文献   
103.
Now that racism has been officially recognized in Brazil, and some universities have adopted affirmative-action admission policies, measures of the magnitude of racial inequality and analyses that identify the factors associated with changes in racial disparities over time assume particular relevance to the conduct of public debate. This study uses census data from 1950 to 2000 to estimate the probability of death in the early years of life, a robust indicator of the standard of living among the white and Afro-Brazilian populations. Associated estimates of the average number of years of life expectancy at birth show that the 6.6-year advantage that the white population enjoyed in the 1950s remained virtually unchanged throughout the second half of the twentieth century, despite the significant improvements that accrued to both racial groups. The application of multivariate techniques to samples selected from the 1960, 1980, and 2000 census enumerations further shows that, controlling for key determinants of child survival, the white mortality advantage persisted and even increased somewhat in 2000. The article discusses evidence of continued racial inequality during an era of deep transformation in social structure, with reference to the challenges of skin color classification in a multiracial society and the evolution of debates about color, class, and discrimination in Brazil.  相似文献   
104.
Research into maximizing the speed, precision, and reliability of estimating the postmortem interval (PMI) has been a recurring object of investigation and methodologies based on the vitreous humor (VH) have provided good results. However, contamination from causes not readily apparent, such as blood, can occur, and thus lead not only to an erroneous estimation of PMI, but also interfere with the correct identification of other substances in the VH. We have developed a flow cytometry method which quantifies blood contamination and is able to detect erythrocytes in 1:750,000 dilution of contaminated VH which affects the results of hypoxanthine. It is an improvement on the previous more complex mass spectrometry method, being faster, more sensitive, and readily available. As such, it could be proposed for the rapid screening of appropriate samples by detecting and eliminating blood contaminated samples from PMI estimation.  相似文献   
105.
106.
Many Americans own guns to protect themselves against other people, but there is evidence that both victimization and gun access increase suicide risk. We conducted qualitative interviews with informants of 17 suicide cases in New Orleans of the 60 who died between January 2015 and April 2016 to understand the relationship between past trauma, gun access and storage, and suicide. Nine cases had experienced a past trauma, including three who had recently had a family member killed by homicide. Eight died via firearm; of those, seven owned the guns they used to take their lives and stored them locked (but loaded) at home or in their cars. Preventing community violence and addressing its sequelae may be important for reducing suicides. A multi‐pronged strategy consisting of policies, education, and marketing will likely be needed to address the risk of suicide conferred by gun access.  相似文献   
107.
108.
Gene and genotype frequencies in relation to the D3S1358, vWA, FGA, TH01, TPOX, CSF1PO, D5S818, D13S317, and D7S820 loci were determined in a sample of 290 unrelated individuals (204 Caucasians and 86 mulattoes) living in the city of S?o Paulo, Brazil. The sex test Amelogenin was also performed in all subjects from our sample, revealing the expected sex in all instances. Allele frequency data obtained from the analysis of these samples were in the usual range of other population groups with similar racial background. In the sample of Caucasian individuals, panmictic proportions were ruled out in relation to TPOX and CSF1PO loci, but only in the latter was the overall frequency of heterozygotes significantly less than expected. In the sample of mulattoes, Hardy-Weinberg proportions were rejected in relation to FGA and CSF1PO loci, but in no instance were the overall numbers of heterozygotes different from the corresponding expected ones under panmixia. Taking into account all this and also the number of tests performed, the degree of genetic heterogeneity of Brazilian populations, and the critical level reached by the significant results (1% < alpha<5%), the departures from panmixia here observed can be considered to be negligible in altering significantly biologic relationship odds calculated under the assumption of random matings.  相似文献   
109.
This fourth article of the series is taking an in‐depth analysis at the visible aging of latent fingermarks regarding changes in ridge widths over time. The objective is to quantify and statistically describe significant ridge size variations under controlled indoor conditions. The effect of three environmental variables are examined: type of secretion (sebaceous‐ and eccrine‐rich) and type of substrate (glass and polystyrene) when aged in three light conditions (direct natural light, shade, and dark). Prior to width measurements, fresh and aged fingermarks were powdered with titanium dioxide (TiO2) and sequentially photographed at predetermined times over 6 months. Three independent observers measured the ridges from thirty predetermined locations using strategically placed intersecting lines on the print. Results indicate that fingermarks deposited on glass are more resilient to degradation compared with those deposited on plastic. The presence of direct natural light plays a negligible role on degradation compared to secretion and substrate types.  相似文献   
110.
The variations found in the elemental composition in ecstasy samples result in spectral profiles with useful information for data analysis, and cluster analysis of these profiles can help uncover different categories of the drug. We provide a cluster analysis of ecstasy tablets based on their elemental composition. Twenty‐five elements were determined by ICP‐MS in tablets apprehended by Sao Paulo's State Police, Brazil. We employ the K‐means clustering algorithm along with C4.5 decision tree to help us interpret the clustering results. We found a better number of two clusters within the data, which can refer to the approximated number of sources of the drug which supply the cities of seizures. The C4.5 model was capable of differentiating the ecstasy samples from the two clusters with high prediction accuracy using the leave‐one‐out cross‐validation. The model used only Nd, Ni, and Pb concentration values in the classification of the samples.  相似文献   
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