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A general toxicology unknown case is presented to demonstrate our systematic approach. A 20-year-old male was found dead with multiple suicide notes. Overdose was suspected but substances were not known. Blood alcohol was negative. Urine was analyzed by enzyme-multiplied immunoassay technique and was negative for all drugs assayed. Urine was then extracted with ethyl acetate:hexane (1:1) at pH 10 and back-extracted into 1.0N sulfuric acid. The acidic layer was adjusted to pH 10, and re-extracted with ethyl acetate:hexane (1:1). The residue was analyzed by gas chromatography (GC) on a 3% OV-101 column. It was found to be negative for all commonly screened substances. However, several unknown peaks were observed. Electron impact mass spectra of these unknown peaks were obtained and searched for in our computer library of more than 25000 mass spectra. These unknown peaks were identified as doxylamine and pyrilamine by gas chromatography/mass spectrometry. The base peak and molecular ion for pyrilamine were at m/z 121 and 285, respectively. The base peak for doxylamine was at m/z 58. No molecular ion was observed for doxylamine. Both doxylamine and pyrilamine are antihistamines, but are promoted and used in the management of insomnia. Quantitation was performed on a GC using dexbrompheniramine as an internal standard. Blood concentrations for doxylamine and pyrilamine were 0.7 and 7.0 mg/L, respectively. Concentrations in other tissues were determined. Death was caused by combined doxylamine and pyrilamine intoxication; the manner of death was suicide.  相似文献   
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Despite recent advancements in the criminological study of stalking, few theoretical tests have been conducted to date to explain stalking victimization among men and women separately. The current study individually and simultaneously extends three criminological theories to the study of stalking victimization: self-control, social learning, and control balance theories. Among a sample of 2,766 university students, a series of models were estimated for men and women separately to assess each set of theoretical variables net of control variables. Results reveal consistent significant positive relationships between stalking victimization and low self-control for men; differential peer association (e.g. friends are stalking victims) for men and women; and several social learning variables for only women. However, the control imbalance variables do not explain stalking victimization among men or women, net of other theoretical and control variables. The utility of a multi-theoretical approach to future stalking victimization research is discussed.  相似文献   
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The current study compared perceptions on self-report measures of university mission identity and social justice attitudes between general university students (151 women, 63 men; M age = 19.72, SD = 1.91) and campus ministry students (64 women, 24 men; M age = 19.85, SD = 1.71). Results demonstrated that campus ministry students scored significantly higher on each of four social justice and global/urban engagement subscales. Implications suggest that perceptions of university mission-identity are linked to social justice attitudes, yet campus ministry students compared to regular student samples may be linked to a stronger emphasis on social justice through campus activity.  相似文献   
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Climate change is projected to dramatically disrupt rainfall patterns and agricultural yields in sub-Saharan Africa. These shocks to food production can mire farming households in poverty traps. This study investigates whether unconditional cash transfers can help households cope with agricultural production and price shocks. We find that cash empowers poor, rural households facing these negative shocks to employ coping strategies typically used by the non-poor and enables them to substantially increase their food consumption and overall food security. Extending relatively small cash payments unconditionally to the rural poor is a powerful policy option for fostering climate-resilient development.  相似文献   
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