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91.
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   
92.
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   
93.
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   
94.
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   
95.
96.
Conventional development of latent fingerprints is compromised when the prints are decomposed by extreme temperatures, such as those encountered when a weapon cartridge is fired, an improvised explosive device is detonated, and/or in arson cases. Understanding how these extreme temperatures alter the chemical and physical properties of latent fingerprint residue could aid in the discovery of a reagent that could effectively develop these decomposed fingerprints. To mimic scenarios where fingerprints may be exposed to high heat conditions, standards of the five most abundant amino acids in fingerprint residue as well as extracted fingerprint residue were pyrolized under controlled conditions. Compounds identified as pyrolytic decomposition products were 3,6-dimethylpiperazine-2,5-dione (from alanine), maleimide, and 2,5-furandione (from aspartic acid). The pyrograms and selected ion traces show these products to hold promise as indicators of decomposed fingerprint residues and, therefore, may serve as good candidate substrates for a developing reagent.  相似文献   
97.
98.
This study describes the development and validation of three Attitudes Towards Male Dating Violence (AMDV) Scales and three Attitudes Towards Female Dating Violence (AFDV) Scales. These scales measure attitudes toward use of psychological, physical, and sexual dating violence, respectively, by boys and by girls. Eight hundred twenty-three students from grades 7, 9, and 11 participated in the validation study. All six scales have good internal consistencies. As predicted, students were more accepting of girls' use of violence than of boys' use of violence, and boys were more accepting of violence than were girls. The six scales were positively correlated with traditional attitudes toward gender roles and with each other, providing evidence for their construct validity. Higher scores on the AMDV Scales were related to boys' past use of violence in dating relationships and to their having aggressive friends, supporting their criterion-related validity. Higher scores on the AFDV Scales were associated with girls' past use of dating violence but not with their having aggressive friends, providing partial support for their criterion-related validity. Singly or in combination, the Attitudes Towards Dating Violence Scales can be used to increase our understanding of the development and maintenance of violence-supportive attitudes in adolescents of all ages.  相似文献   
99.
Bestiality is a serious although less frequently occurring form of animal cruelty that may be linked to subsequent aggression against humans. This investigation examines whether a perpetrator's race, childhood residence, education, commission of a personal crime, and the number of personal crimes committed affects acts of bestiality committed during childhood or adolescence among a sample of incarcerated males. The results show that respondents with less education and those who had been convicted of committing crimes against people on one or more occasions were more likely to have had sex with animals during their childhood or adolescence than other respondents in the sample. These findings lend some support to the sexually polymorphous theory that among these perpetrators sex and aggression have become mutually inclusive and that bestiality as a form of animal cruelty may be linked with interpersonal human violence.  相似文献   
100.
This study examined microcrystals formed by silver with gamma-hydroxybutyric acid (GHB) and gamma-hydroxyvaleric acid (GHV), the five-carbon analog of GHB, in the presence of silver, copper, and lanthanide nitrates. Distinct microcrystals formed with silver (+1) and lanthanum (+3) ions but not with the copper (+2) ions. The crystals formed with GHB were distinctly different than those formed with GHV and in all cases, the drug microcrystals were easily distinguishable from reagent crystals. X-ray diffraction analysis provided definitive structure for the microcrystals. The morphological differences between the silver-GHB and silver-GHV crystals were characterized using simple measurements such as size and angles provided by image recognition software. The utility of the test for casework was demonstrated using spiked beverage samples.  相似文献   
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