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941.
Women's labor force participation and earnings dramatically increased after World War II. Those changes have important implications for women's Social Security benefits. This article uses the Social Security Administration's Modeling Income in the Near Term (version 6) to examine Social Security benefits for current and future beneficiary wives. The projections show that fewer wives in more recent birth cohorts will be eligible for auxiliary benefits as spouses because their earnings are too high. If their husbands die, however, most wives will still be eligible for survivor benefits because, despite the increase in their earnings over time, they still typically have lower earnings than their husbands. Even so, the share of wives who would be ineligible for widow benefits is projected to double between cohorts. 相似文献
942.
Blacks, Hispanics, and divorced women have historically experienced double-digit poverty rates in retirement, and divorce and other demographic trends will increase their representation in future retiree populations. For these reasons, we might expect an increase in the proportion of economically vulnerable divorced women in the future. This article uses the Social Security Administration's Modeling Income in the Near Term (version 6) to describe the likely characteristics, work experience, Social Security benefit status, and economic well-being of future divorced women at age 70 by race and ethnicity. Factors associated with higher retirement incomes include having a college degree; having a strong history of labor force attachment; receiving Social Security benefits; and having pensions, retirement accounts, or assets, regardless of race and ethnicity. However, because divorced black and Hispanic women are less likely than divorced white women to have these attributes, income sources, or assets, their projected average retirement incomes are lower than those of divorced white women. 相似文献
943.
The Italian party system largely collapsed in the early 1990s, providing us with a natural experimental situation in which voters were confronted with new parties – indeed, with an entirely new party system. How did they react? This paper develops a number of expectations on the basis of existing theory and tests these expectations using a dataset consisting of election studies conducted in Italy between 1985 and 2008. We find that a new party system causes confusion as to where parties stand in left-right terms, making it difficult for voters to make their choices on the basis of ideological cues. The confusion is greatest among older voters – those already set in their habits of voting, but only the very oldest cohorts (containing voters over 60 years old) are significantly debilitated. 相似文献
944.
Generally speaking, campaign-related contact motivates voters. One form of such contact not much explored in the voter mobilization
literature is the petitioning for ballot initiatives that occurs with considerable frequency in about half the states and
even more localities. Using newly-available data that allow us to match individual petition signers with their subsequent
election behavior, we explore the role of having had a hand in a ballot measure’s qualifying stage in propelling individual
voters to the polls. Specifically, we perform multivariate analysis on a random sample of 1,000 registered Arkansas voters,
1,100 registered Florida voters, and all 71,119 registered voters in Gainesville, Florida to measure the influence of petition-signing
in spurring voter turnout. We find marginal effects in the statewide samples, but substantial and significant turnout effects
in the Gainesville municipal election—an off-cycle, low-profile election. Furthermore, the effect of petition-signing—across
all of our samples—is strongest among irregular, as compared to habitual, voters. These findings are in keeping with recent
campaign mobilization experimental research and comport with previous findings on the “educative effects” of ballot measures
on voter turnout. 相似文献
945.
STAR METRICS is a data platform that is being voluntarily and collaboratively developed by U.S. federal science agencies and research institutions to describe investments in science and their results. It initially emerged as a result of reporting requirements associated with the 2009 American Recovery and Reinvestment Act; it has developed in response to a recognized need to begin to systematically document federal investments in science and their immediate and long‐term results. The eventual goal is to draw information from existing data on scientific and economic activities as well as from research institutions' and federal science agencies' systems to provide data that can be used for a more scientific analysis of science investments and their outcomes. 相似文献
946.
Carnivore scats recovered from animal attack and/or scavenging contexts frequently contain forensic evidence such as human bone fragments. Forensic cases with carnivore involvement are increasingly prevalent, necessitating a methodology for the recovery and analysis of scat evidence. This study proposes a method for the safe preparation of carnivore scat, recovery of bone inclusions, and quantification and comparison of scat variables. Fourteen scats (lion, jaguar, lynx, wolf, and coyote) were prepared with sodium-acetate-formalin fixative; analytical variables included carnivore individual, species, body size, and taxonomic family. Scat variables, particularly bone fragment inclusions, were found to vary among carnivore individuals, families, species, and sizes. The methods in this study facilitate safe scat processing, the complete recovery of digested evidence, and the preliminary identification of involved animals. This research demonstrates that scat collected from forensic contexts can yield valuable information concerning both the victim and the carnivore involved. 相似文献
947.
Moreno LI Tate CM Knott EL McDaniel JE Rogers SS Koons BW Kavlick MF Craig RL Robertson JM 《Journal of forensic sciences》2012,57(4):1051-1058
The potential application of mRNA for the identification of biological fluids using molecular techniques has been a recent development in forensic serology. Constitutively expressed housekeeping genes can assess the amount of mRNA recovered from a sample, establish its suitability for downstream applications, and provide a reference point to corroborate the identity of the fluid. qPCR was utilized to compare the expression levels of housekeeping genes from forensic-like body fluid stains to establish the most appropriate assessment of human mRNA quantity prior to profiling. Although variability was observed between fluids and individuals, results indicated that beta-2 microglobulin exhibited the highest expression for all body fluids examined and across donors. A one-way analysis of variance was performed for housekeeping gene variability between donors (at the α, 0.05, significance level), and the results indicated significant differences for semen, vaginal secretions, and menstrual blood. 相似文献
948.
De Grazia A Mikhael M Stojanovska N Reedy B Shimmon R Tahtouh M 《Forensic science international》2012,216(1-3):189-197
In 1979, Miller and Patel showed that a solution containing two diacetylene monomers, 2,4-hexadiyne-1,6-bis(phenylurethane) (HDDPU) and 2,4-hexadiyne-1,6-bis(p-chlorophenylurethane) (HDDCPU) could be used to develop latent fingermarks on a non-porous surface. In the current work, the same mixture (HDDPU:HDDCPU=10:1, in acetone solution) was used to develop fingermarks on a wide variety of surfaces, both non-porous and porous, including paper. An airbrush system was optimized for the application of the reagent solution. Once the solution evaporates on a surface, the monomers co-crystallize in different ways, depending upon a number of factors, including the surface residue. "Active" co-crystallization leads (with heat or radiation) to the formation of purple polymer, while "inactive" crystallization results in a non-polymerizable white deposit. Fingermark contrast was achieved as a result of active co-crystallization (giving purple polymer) in either the ridges or the furrows, depending upon the surface and other factors. A general observation (supported by spot tests with linseed oil, salt and amino acid solutions) was that on paper, oily materials are more likely to lead to the formation of the purple polymer, while the presence of water inhibits polymerization. However, these observations are not consistent across all other substrates. It is hypothesized that water disrupts hydrogen bonding between diacetylene molecules, and thus prevents the topochemical polymerization of the diacetylenes, which occurs in the solid state between favourably aligned monomers. An interesting observation was the development of fingermarks deposited on paper that had already been treated with the diacetylene reagent. 相似文献
949.
Bolton-King RS Bencsik M Evans JP Smith CL Allsop DF Painter JD Cranton WM 《Forensic science international》2012,220(1-3):197-209
This paper demonstrates a numerical pattern recognition method applied to curvilinear image structures. These structures are extracted from physical cross-sections of cast internal pistol barrel surfaces. Variations in structure arise from gun design and manufacturing method providing a basis for discrimination and identification. Binarised curvilinear land transition images are processed with fast Fourier transform on which principal component analysis is performed. One-way analysis of variance (95% confidence interval) concludes significant differentiation between 11 barrel manufacturers when calculating weighted Euclidean distance between any trio of land transitions and an average land transition for each barrel in the database. The proposed methodology is therefore a promising novel approach for the classification and identification of firearms. 相似文献
950.
Identification of an ignitable liquid in fire debris evidence can be complicated due to evaporation of the liquid, matrix interferences, and thermal degradation of both the liquid and the matrix. In this research, liquids extracted from simulated fire debris were compared to the original liquid using multivariate statistical procedures. Neat and evaporated gasoline and kerosene standards were spiked onto nylon carpet, which was subsequently burned. The ignitable liquid residues were extracted using a passive headspace procedure and analyzed by gas chromatography-mass spectrometry. Pearson product moment correlation coefficients, hierarchical cluster analysis, and principal components analysis were used to compare the liquids extracted from the carpet to the corresponding neat liquid. For each procedure, association of the extracts according to liquid type was possible, albeit not necessarily to the specific evaporation level. Of the three procedures investigated, principal components analysis offered the most promise since contributions from matrix interferences were essentially eliminated. 相似文献