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The Scent Transfer Unit (STU-100) is a portable vacuum that uses airflow through a sterile gauze pad to capture a volatiles profile over evidentiary items for subsequent canine presentation to assist law enforcement personnel. This device was evaluated to determine its ability to trap and release organic compounds at ambient temperature under controlled laboratory conditions. Gas chromatography-mass spectrometry (GC-MS) analyses using a five-component volatiles mixture in methanol injected directly into a capture pad indicated that compound release could be detected initially and 3 days after the time of collection. Additionally, 15 compounds of a 39-component toxic organic gaseous mixture (10-1000 parts per billion by volume [p.p.b.(v)]) were trapped, released, and detected in the headspace of a volatiles capture pad after being exposed to this mixture using the STU-100 with analysis via GC-MS. Component release efficiencies at ambient temperature varied with the analyte; however, typical values of c. 10% were obtained. Desorption at elevated temperatures of reported human odor/scent chemicals and colognes trapped by the STU-100 pads was measured and indicated that the STU-100 has a significant trapping efficiency at ambient temperature. Multivariate statistical analysis of subsequent mass spectral patterns was also performed.  相似文献   
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The study investigates the presence of tetrahydrocannabinols in the head hair and the pubic and axillary hair. The hair samples were obtained from hashish smokers. The concentrations were determined by radioimmunoassay and reflect total tetrahydrocannabinols and metabolites. The values found ranged from 0.4 ng/mg hair up to 3.8 ng/mg hair. The presence of the drug in the hair samples was also demonstrated by GC/MS.  相似文献   
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Mara Salvatrucha (MS‐13), founded in 1980s Los Angeles by Salvadoran immigrant youth, is today one of the largest street gangs in North and Central America. In recent years the group has acquired a reputation for extreme brutality and has ostensibly mutated into a fast‐expanding, transnational organized crime network with possible ties to international terrorists. Drawing on key concepts in gang research and multiple methodological tools, this article seeks to sharpen understanding of MS‐13's structure and activities. While the group is active in many countries, it is transnational only in a symbolic manner, not in its configuration or span of authority. Impelled largely by Central American gang‐suppression policies, MS‐13 has evolved from a traditional street gang into a group with organized crime characteristics, but it remains a social phenomenon rooted in urban marginality. Ultimately, a more nuanced picture of Mara Salvatrucha can inform the search for more effective gang policies.  相似文献   
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Apart from collisions with road or rail vehicles and falls from height, self inflicted blunt force is a rare suicide method and mainly seen in psychiatric patients. The paper presents a rare case of suicide by active blunt force. A 68-year-old man committed suicide by repeatedly hitting his head with a stone. He sustained a craniocerebral trauma and finally died from hypothermia due to the low outdoor temperature. According to the relatives, the man was not diagnosed with a mental disorder or suicidal tendencies. Uncommon manners of self-harm are challenging for those involved in the investigation, and a differentiation between suicide, accident and homicide can only be made in synopsis of all findings.  相似文献   
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Alcohol use is related to child physical abuse, although little is known about gender-specific risks factors. This study examines the relationships between alcohol outlets, context-specific drinking, dose–response drinking and child physical abuse for mothers and fathers. Telephone interviews were conducted with 1973 female and 1050 male respondents in 50 California cities. Weighted negative binomial models were used to calculate the frequency of physical abuse in the past year. Drinking more often at restaurants was related to higher frequency of physical abuse for fathers, while mothers who drank more frequently at bars and parties used physical abuse more often. There were no significant dose–response drinking relationships for fathers. Drinking higher amounts at bars, parties, and restaurants was associated with less frequent physical abuse for mothers. Our findings suggest that a focus on drinking contexts may reveal heightened risk for many mothers who do not consume large amounts of alcohol.  相似文献   
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Recent national events have brought the issue of police-community relations into the public eye. Even though a large body of academic research exists on the predictors of public attitude toward police, very little is known about how public perceptions of police accountability influence satisfaction with the police. This study seeks to fill that gap by using ordered logistic regression and multi-year community-level survey data from one Western city (n = 3725) to examine the relationship between satisfaction with police accountability and overall attitudes toward the police. The results indicate that respondent satisfaction with police accountability was a strong, consistent predictor of satisfaction with local police, even after controlling for other important variables, such as race/ethnicity and community context. The findings suggest that public perceptions relating to the control of police officer conduct should be considered when assessing the predictors of attitudes toward the police.  相似文献   
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