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991.
School vouchers are the most contentious form of parental school choice. Vouchers provide government funds that parents can use to send their children to private schools of their choice. Here we examine the empirical question of whether or not a school voucher program in Washington, DC, affected achievement or the rate of high school graduation for participating students. The District of Columbia Opportunity Scholarship Program (OSP) has operated in the nation's capital since 2004, funded by a federal government appropriation. Because the program was oversubscribed in its early years of operation, and vouchers were awarded by lottery, we were able to use the “gold standard” evaluation method of a randomized experiment to determine what impacts the OSP had on student outcomes. Our analysis revealed compelling evidence that the DC voucher program had a positive impact on high school graduation rates, suggestive evidence that the program increased reading achievement, and no evidence that it affected math achievement. We discuss the implications of these findings in light of recent policy developments including the reauthorization of the OSP and the enactment or expansion of more than a dozen school voucher or voucher‐type programs throughout the United States in 2011 and 2012.  相似文献   
992.
PURPOSE: Whether lifetime abstainer's antisocial behavior are maladjusted or well-adjusted is unresolved. The aim of this study was to compare abstainers (defined as persons with no lifetime use of alcohol and other drugs and non-engagement in antisocial or delinquent behavior) with non-abstainers across a range of sociodemographic and mental health characteristics in the United States. METHODS: Data were derived from the National Epidemiologic Survey on Alcohol and Related Conditions, a nationally representative sample of U.S. adults. Structured psychiatric interviews (N = 43,093) using the Alcohol Use Disorder and Associated Disabilities Interview Schedule - DSM-IV version (AUDADIS-IV) were completed by trained lay interviewers between 2001 and 2002. RESULTS: The prevalence of abstaining was 11%. Abstainers were significantly more likely to be female, Asian and African-American, born outside the U.S., and less likely to be unemployed. Multivariate logistic regression analyses revealed that abstainers were significantly less likely to evidence lifetime mood, anxiety, or personality disorder compared to non-abstainers. CONCLUSIONS: Findings indicate that abstainers are not maladapted and are comparatively more functional than non-abstainers.  相似文献   
993.
Porcine tissue samples shot with two different types of bullets, jacketed and nonjacketed, were collected in the fresh state and throughout moderate decomposition. Wound samples were microwave-digested and analyzed using inductively coupled plasma mass spectrometry (ICP-MS) to detect all elements present at measurable levels in gunshot residue (GSR). Elements detected included antimony (Sb), barium (Ba), and lead (Pb), which are considered characteristic of GSR, as well as iron (Fe) and copper (Cu). These five elements were used to differentiate shot tissue and unshot tissue, as well as tissue shot by the two different bullet types, both in the fresh state and throughout moderate decomposition. The concentrations of Cu, Sb, and Pb were able to distinguish the two bullet types in fresh tissue samples at the 95% confidence level. Cu and Pb were able to differentiate the bullet types throughout moderate decomposition at the 99% confidence level.  相似文献   
994.
995.
The current study examines the utility of self-trauma theory for explaining the long-term impact of childhood psychological abuse on aggression. Specifically, the self-capacities of interpersonal relatedness, identity, and affect regulation are tested as mediators of the impact of psychological abuse on various types of aggression in adulthood. Hierarchical regression analyses are used to examine data collected from 268 university students who completed the Personality Assessment Inventory, Comprehensive Child Maltreatment Scale, and the Inventory of Altered Self-Capacities. Results show that self-capacities were predicted by maltreatment, particularly psychological abuse. Altered self-capacities fully mediate the impact of child maltreatment on various forms of aggression. Problems with interpersonal relationships play the most significant role in mediating the relationship between child maltreatment and aggression. Results suggest more frequent maltreating experiences predict more dysfunctional self-capacities, which increases the probability of displaying various forms of aggression.  相似文献   
996.
Abstract: With sexual assault evidence, the visualization of spermatozoa confirms that ejaculation has occurred. However, microscopic examination of spermatozoa is a laborious process and can sometimes result in sperm cells being overlooked. Here, we present the developmental validation of the SPERM HY‐LITER? kit, which contains a human sperm–specific mouse monoclonal antibody coupled to a fluorescent Alexa 488 dye. The kit was tested using samples of human semen, saliva, blood, and urine, various animal semen extracts, sexual lubricants, and a commercially available spermicidal film. Postcoital vaginal swabs, degraded semen samples, and samples prepared with sample fixation techniques that deviated from the kit‐provided protocol were also tested. In each case, the SPERM HY‐LITER? kit was demonstrated to bind only to human sperm cell heads. Limitations to this fluorescent staining procedure include nonspecific staining and increased background fluorescence with extreme heat fixation in some samples.  相似文献   
997.
Four novel alkyl 2-cyanoacrylate monomers (alkyl=1-cyanoethyl, 2-cyanoethyl, trideuteromethyl and pentadeuteroethyl) have been tested for their ability to develop latent fingermarks that can then be visualized using mid-infrared spectral (chemical) imaging. Each of the four monomers was chosen for its potential to produce a strong, isolated infrared spectral band in its corresponding polymer (to provide spectral contrast against most backgrounds), as well as for its potential ability to be fumed onto fingermarks in the manner of conventional ethyl 2-cyanoacrylate (superglue). With the exception of the 2-cyanoethyl 2-cyanoacrylate, which had to be fumed under reduced pressure, all of the monomers were found to be sufficiently volatile to be fumed in a conventional fuming cabinet. All four monomers polymerized selectively on fingermark ridges on a variety of non-porous and semi-porous surfaces, leading to excellent development of the fingermarks. Unfortunately, although high quality mid-infrared spectral images of the fingermarks could be formed for all of the polymers at various frequencies, the new CN or CD stretching vibrations did not give rise to strong enough absorption intensities for good contrast on difficult backgrounds such as polymer banknotes. However, in the 1-cyanoethyl 2-cyanoacrylate polymer, the presence of the additional nitrile group had the unintended but desirable effect of shifting the strong CO absorption to higher frequencies, moving it away from interfering banknote absorptions. This enabled fingermark contrast to be achieved even against the intaglio printing on the banknotes.  相似文献   
998.
999.
For many of Russia's poorest people, and especially for the officially recognized ‘indigenous small-numbered peoples’, neoliberal reforms following the collapse of the Soviet Union represented a major retrenchment in ‘social citizenship’ as defined by T.H. Marshall. However, some reforms also promised increased civil, political and cultural citizenship rights, which Russia's indigenous peoples have sought to realize through new legislation and appeals to international agreements regarding the rights of indigenous peoples. But with Russia's current economic and political course geared towards maximizing revenues from the extraction and sale of natural resources, Russia's indigenous peoples have been frustrated in their efforts to realize these citizenship rights, particularly in their attempts to assert rights to land and resources through legal means. This paper draws on case studies from southern Siberia to discuss first how Russia's identity politics and an international focus on indigenous peoples have combined to create indigenous subjects in the Russian Federation, and second how the anticipated transition from indigenous subjects to indigenous citizens has for the most part failed to materialize.  相似文献   
1000.
Small arms must be considered as a public health problem, but quantifying the public health impact of small arms is difficult and studies are sparse in areas of conflict. This study considers the remote cross border area between Kenya and Uganda where pastoral conflict in the form of cattle raiding with the use of small arms has escalated in recent years, and where health facilities are scarce. Hospitals and clinics in Karamoja, Uganda, and West Pokot, Kenya were visited by the author, to collect any available data on small arms injuries. Interviews with hospital staff helped to provide further insight into the statistics. Statistics showed that most injuries were sustained during raiding, though worrying incidences of injury among noncombatants and young children were found. Many serious injuries and limb fractures were documented, likely to have some long-term implications for pain, growth, disability, and livelihood. Deaths and injuries are likely to be significantly underestimated by the statistics, due to problems of transport, insecurity, deaths prior to arrival, admission fees for some facilities, and fear of reporting injuries due to the criminal element. Police statistics support this conclusion. The situation appeared to be worse in Uganda as opposed to Kenya, but cooperation between the two countries is needed since pastoralists readily cross the borders both to raid and to attend clinics and hospitals.
Kennedy Agade MkutuEmail:
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