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101.
A simple microfluidic device (MFD) has been developed to perform multiple color and crystal tests for controlled substance analysis. The MFD method uses less sample and reagents and generates less waste than traditional spot plate methods while performing several tests simultaneously. This methodology provides significantly more analytical information for a single sample analysis. The current generation device is the size of a microscope slide with four analytical channels: one for microcrystal tests and three for color tests. The optimized devices were subjected to a rigorous validation study using comparative replicate analyses and several operators. Target analytes were methamphetamine, amphetamine, cocaine, and oxycodone and color test reagents used were the Marquis, Simon, and cobalt thiocyanate. For the crystal tests, platinic chloride was used. The validation study showed the MFD's limits of detection to be in the picogram range. Positive tests results were observed in complex mixtures in which the controlled substance was present at concentrations of 5-10% (w/w). The microcrystal reagents showed greater sensitivity than color test reagents when used in the device. Reagent use and waste generation using the devices was 95% less that that used and generated using the traditional methods. The device performance was also shown to be operator independent.  相似文献   
102.
The purpose of this study was to identify sociodemographic, contextual, situational, and individual variables, as well as certain behavioral warning signs, associated with filicide as a function of sex of the agressors and the presence or absence of self-destructive behaviours. The data cover all officially registered filicides committed in Quebec from January 1, 1986, to March 31, 1994, against youths under the age of 18 years. For the group of individuals who have self-destructive behaviours, results indicate that men compared to women are more likely to commit spousal homicide, to kill a higher number of victims, to be going through a conjugal separation, to have committed conjugal violence, to have threatened suicide, and to have threatened to kill their spouse. For the group of individuals who commit no self-destructive acts, women are more likely to present with a depressive disorder, whereas men are more likely to maltreated their children. Men who do not commit a self-destructive act are characterized by a significantly higher likelihood of maltreatment against their children and of tyrannical discipline, whereas men who commit a self-destructive act perpetrate filicide as a means of reprisal against their spouse. Results underscore the importance of considering the different groups of individuals who commit filicide as a function of sex as well as presence or absence of self-destructive behaviour.
Suzanne LéveilléeEmail: Email:
  相似文献   
103.
Abstract: This report describes the identification of a merchant mariner who perished in 1948 when Northwest Airlines Flight 4422, a DC‐4 carrying 24 seamen and six crew members crashed into Mount Sanford, Alaska. Fifty‐one years later, a human forearm and hand were found close by the wreckage of the plane, prompting identification efforts using DNA and fingerprints. There were significant challenges to both the fingerprint and DNA analyses. The hand was badly desiccated, making fingerprint friction‐ridge detail almost invisible and the remains had been embalmed upon discovery, making DNA amplification difficult. We present the results of an interdisciplinary approach that successfully addressed these challenges and ultimately led to the identification of the remains. These efforts relied on efficient fingerprint rejuvenation and imaging techniques that improved print resolution, as well as new DNA extraction techniques optimized for aggressively embalmed remains.  相似文献   
104.
An emerging issue that has gained the attention of the media and environmental activists in the United States over the past decade is the contamination of the United States’ drinking water supply. The alleged contaminants in the nation's water supply have ranged from methyl tertiary-butyl ether and coal by-products to pesticides and herbicides. Although these threats have drawn the attention of the media and activists, federal, state, and local regulators have been slow to respond. As a result, water contamination lawsuits are becoming more prevalent.  相似文献   
105.
The German colonial world was marked by an ostensibly self-evident boundary between the white ruler and the black ruled that situated Europeans and indigenous peoples as diametrically opposed and socially discrete. This situation, however, was problematised by the gendered and sexualised interactions between European and indigenous society. The result was often a slippage between the administrative attempts to create recognisably ‘German’ families (perceived in racial terms), and the antinomian realities of human relationships that transgressed racial lines. This in turn gave rise to reproductive anxieties in the face of a new liminal population of ‘half-castes’ (Mischlinge) that refused the white–black, master–slave dialectic of the colonial ideal. Many historians have recently attempted to link the troubled history of race relations in German Southwest Africa to the later history of Nazi anti-Semitism and genocide, by focusing on the apparent continuities between the Holocaust and the Herero–Nama wars. However, an alternative genealogy for the Holocaust that refutes this genocidal continuity thesis is possible through an investigation of the origins and contents of the debates about the nature of the German colonial family and its relationship to German citizenship between 1904 and 1914.  相似文献   
106.
The present study went beyond previous cross-national homicide research, which has largely focused on combined (male and female) rates of homicide offending, by using gender-disaggregated homicide arrest figures. The study included controls for the clearance rate and the percentage of homicides that were attempts, and included data for forty-eight countries across multiple levels of development. The author compared the effects of development/modernization and opportunity on female homicide rates to their effects on male homicide rates. Results indicated that, overall, structural predictors had very similar effects on male and female homicide rates. Both rates were lower in countries with a higher gross domestic product (GDP) per capita, and neither male nor female homicide rates were related to urbanization. Countries with a higher number of people per household had a lower rate of both male and female homicide offending; however, this relationship only held when percent young was excluded from the model.  相似文献   
107.
Fitzpatrick L 《Time》2007,170(21):59
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108.
Although the use of strategic planning has become widespread in INGDOs they have often been accused of strategic drift—continuous change in their strategic directions with plans only loosely coupled to their activities. However, the way that they prioritize their activities, and the reasons why strategic drift occurs has generally escaped in‐depth research. This article draws on detailed, qualitative research of strategic planning meetings at the executive levels in a major INGDO, carried out between July 2006 and December 2007 to identify the reasons why strategic drift occurs and the role of strategic planning. It was found that by deliberately crafting multiple, ambiguous, and ambitious strategies, managers were able to effect organizational change, not by literal strategy implementation, but by using these strategies as metaphors to harness consensus and legitimacy in key stakeholder groups. Senior managers utilize the symbols, language and deliberative arenas of formal strategic planning to effect organizational change; however, strategy, in rational terms, needs to be located in the background for its role to be properly understood. The research unpacks complex decision‐making processes in an INGDO and, contrary to normative literature, recommends that, in order to avoid inflationary planning, managers should not take their strategy literally. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
109.
The purpose of the current investigation was to examine relations among maternal regulatory support, maternal antagonism, and mother–son relationship quality in relation to boys’ self-regulation during early adolescence. As part of a larger longitudinal study on 263 low-income, ethnically diverse boys, multiple informants and methods were used to examine associations among parenting practices and mother–son relationship quality in relation to boys’ self-regulation at ages 10 and 11. Multivariate analyses indicated that high levels of regulatory supportive parenting and relationship quality and low levels of antagonistic parenting independently predicted high levels of boys’ self-regulation at age 10. Only antagonistic parenting and relationship quality explained variance in levels of boys’ self-regulation at age 11 after accounting for prior self-regulation. The findings suggest that parenting and the context of the parent–child relationship are linked to self-regulation during early adolescence; however, it appears that parental antagonism and relationship quality, not maternal regulatory supportive parenting, contribute to rank-order change in self-regulation abilities. Implications of these results for research and practice are discussed.  相似文献   
110.
This study investigated age- and gender-specific associations between parental support and parental knowledge of the child’s whereabouts, on the one hand, and sexual experience and sexual health (the ability to have safe and pleasurable sexual experiences) on the other hand. A representative Dutch sample of 1,263 males and 1,353 females (aged 12–25 years), who had previously engaged in sexual intercourse, completed a questionnaire that included measures of these constructs. Both parental support and knowledge were positively associated with contraceptive use, social skills in sexual interactions, sexual satisfaction, and delay of sexual debut. Findings also revealed that the majority of correlations between parental support and sexual experience and sexual health are attributable to the relationship between a supportive family environment and parental knowledge of the child’s whereabouts. Parental knowledge thus appeared to be more important for healthy sexual development than parental support.  相似文献   
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