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The presence of cocaine in illicit drug samples is still being determined in some laboratories using spot tests and microcrystal tests. Seventeen chemical species were tested using three different spot tests (Wagner, Marquis, and cobalt thiocyanate followed by stannous chloride reactions) and two microcrystal tests (gold chloride and platinic chloride) to determine whether the results could be differentiated from the results of these tests on cocaine. The data obtained indicated that nine of the 17 compounds gave results similar to those from cocaine using the three spot tests, but that the results from microcrystal testing allowed for differentiation of all nine compounds from cocaine.  相似文献   
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Reno J 《Newsweek》2001,138(6):42
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Journal of Family Violence - Research suggests that breastfeeding may reduce child maltreatment risk. Alaska has high rates of both breastfeeding initiation and maltreatment reports to Child...  相似文献   
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We sought to determine whether intimate partner violence (IPV) risk factors differed depending upon the presence of children in the home, and to estimate the annual prevalence of IPV first in the general population and then in homes with and without children. We analyzed data from a cross-sectional random sample of 6,836 women in southeastern Pennsylvania interviewed by telephone in 2004. The magnitude of association between IPV and risk factors varied between homes with and without children for women’s alcohol problems (with children, odds ratio (OR) 7.7; 95% confidence interval (CI) 2.9, 20.9; without children, OR 2.4; 95% CI 0.9, 6.0), and mental health problems (with children, OR 4.0; 95% CI 1.8, 8.9; without children, OR 3.0; 95% CI 1.6, 5.7). Poverty was significantly associated with IPV only in homes without children (OR 3.6; 95% CI 1.9, 7.2). Annual IPV prevalence was 1.2% overall, 1.4% in homes with children, and 1.1% in homes without children. One in 63 children lived in a home with IPV. Differences in IPV risk factors in homes with and without children suggest distinct underlying IPV mechanisms or consequences in these contexts.  相似文献   
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In homicide investigations, it is critically important that postmortem interval and postburial interval (PBI) of buried victims are determined accurately. However, clandestine graves can be difficult to locate; and the detection rates for a variety of search methods (ranging from simple ground probing through to remote imaging and near‐surface geophysics) can be very low. In this study, simulated graves of homicide victims were emplaced in three sites with contrasting soil types, bedrock, and depositional environments. The long‐term monthly in situ monitoring of grave soil water revealed rapid increases in conductivity up to 2 years after burial, with the longest study evidencing declining values to background levels after 4.25 years. Results were corrected for site temperatures and rainfall to produce generic models of fluid conductivity as a function of time. The research suggests soilwater conductivity can give reliable PBI estimates for clandestine burials and therefore be used as a grave detection method.  相似文献   
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The economic well-being of both working and retired persons has improved significantly since the Social Security Act was passed in 1935. More people are employed now than at any time since then, despite declining employment among the aged and more years of school attendance among the young. The ratio of non-workers to workers--a broad measure of dependency--is lower now than at any time since the 1930's. Social security has grown and matured to become a strong foundation of retirement income, and other work-related employee benefits have grown in tandem with social security. Employer contributions for social insurance and related employee benefits have grown from being about a 1-percent supplement to aggregate wages and salaries in 1929 to nearly 20 percent today. Social security and Medicare account for just over a fourth of employer contributions, while other public and private retirement systems represent just over another fourth. The balance of benefits for active workers includes group health and life insurance, unemployment insurance, workers' compensation, temporary disability insurance, and related benefits. Pay for holidays, vacations, and sick leave is estimated to have increased from less than 1 percent of aggregate pay in 1929 to about 10 percent today. The improved economic status of the aged has been documented by a series of surveys beginning in 1941-42 and carried out from time to time until 1972 and biennially since 1976. The earlier surveys were supplemented with estimates from record data and tables from the Bureau of the Census. The income of the aged as a whole has grown by about 75 percent over the past 2 decades after taking inflation into account. The income of the aged as a whole grew faster than that of the nonaged in the 1970's and early 1980's when real social security benefits increased faster than inflation and wages lagged behind it. New beneficiaries in 1982 were in better health and were more likely to retire because they wanted to than was true of their counterparts in the early 1940's. Not only have benefits continued to be the main component of income of the aged as total incomes have grown, but also benefits have become much larger in relation to average earnings than used to be the case. Retired workers are much more likely now than in the early 1940's to have other pensions or income from assets to supplement benefits.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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