Volatile organic compounds (VOCs) are by-products of cadaveric decomposition and are responsible for the odor associated with decomposing remains. The direct link between VOC production and individual postmortem microbes has not been well characterized experimentally. The purpose of this study was to profile VOCs released from three postmortem bacterial isolates (Bacillus subtilis, Ignatzschineria indica, I. ureiclastica) using solid-phase microextraction arrow (SPME Arrow) and gas chromatography–mass spectrometry (GC-MS). Species were inoculated in headspace vials on Standard Nutrient Agar and monitored over 5 days at 24°C. Each species exhibited a different VOC profile that included common decomposition VOCs. VOCs exhibited upward or downward temporal trends over time. Ignatzschineria indica produced a large amount of dimethyldisulfide. Other compounds of interest included alcohols, aldehydes, aromatics, and ketones. This provides foundational data to link decomposition odor with specific postmortem microbes to improve understanding of underlying mechanisms for decomposition VOC production. 相似文献
Delinquent behavior is common during adolescence and may disrupt trajectories of labor market attainment. Estimates of the relationship between delinquency and employment are threatened by selection bias, as youth who engage in delinquency often differ substantially from youth who do not. The current study examined the association between adolescents’ engagement in serious delinquency and four measures of occupational attainment in young adulthood: unemployment, personal earnings, employer-provided benefits, and occupational earnings. It examined the effect of delinquency independent of between-person differences in a variety of attributes and tested whether the hypothesized relationship was mediated by educational attainment, work experience, disconnectedness from both education and work, or criminal justice sanctioning. This study analyzed data from the first four waves of the National Longitudinal Survey of Adolescent to Adult Health (Add Health), yielding an analytic sample of 14,800 (51% female, mean age 16 years). The Wave 1 Add Health survey was administered in 1994–1995, and Wave 4 of the survey was administered in 2007–2008. The analytic strategy, propensity score weighting, produced estimates that were less biased by differences between youth who had and who had not engaged in delinquent behavior. The study found that delinquency was significantly associated with the likelihood of being unemployed: compared to non-delinquents, delinquents were more likely to be unemployed even after controlling for temporally prior traits and resources, human capital, and criminal justice contact. The results provided more qualified support for hypothesized relationships between delinquency and job quality. The study concluded that offending may result in less fruitful job searches, but once a search results in employment, employed delinquents are not readily discernible from employed non-delinquents in the quality of their jobs. These conclusions contribute to literature on the labor market outcomes of people with histories of adolescent delinquency as they enter young adulthood.
As transgender and gender-expansive (TGE) youth and young adults (YYA) navigate challenging environments, they often seek spaces for safety and acceptance. This study explores ways in which a group of TGE YYA who were engaged with a community-based service organization make sense of their experiences, challenges, and successes in ways that illuminate the factors and processes associated with resilience. Secondary data analysis was conducted on qualitative responses from 85 TGE YYA ages 13–24. The themes that emerged provide insight into the ways community-based programs and providers can understand and support the resilience of TGE YYA. 相似文献
Self-harm is widely recognized as a significant adolescent social problem, and recent research has begun to explore its etiology.
Drawing from Agnew’s (1992) social psychological strain theory of deviance, this study considers this issue by testing three hypotheses about the effects
of traditional and cyber bullying victimization on deliberate self-harm and suicidal ideation. The data come from a school-based
survey of adolescents in a rural county of a southeastern state (n = 426); 50% of subjects are female, their mean age was 15 years, and non-Hispanic whites represent 66% of the sample. The
analysis revealed that both types of bullying are positively related to self-harm and suicidal ideation, net of controls.
Moreover, those relationships are partially mediated by the negative emotions experienced by those who are bullied and partially
moderated by features of the adolescent’s social environment and self. Regarding the latter, exposure to authoritative parenting
and high self-control diminished the harmful effects of bullying victimization on self-harm and suicidal ideation. The article
concludes by discussing the implications of these conclusions for future research and for policy efforts designed to reduce
self-harm. 相似文献
The consumption of Delta9-tetrahydrocannabinol (THC) as cannabis has been shown to result in impaired and culpable driving. Testing drivers for the presence of THC in blood is problematic as THC and its metabolites may remain in the blood for several days following its consumption, even though the drug may no longer have an influence on driving performance. In the present study, the aim was to assess whether performance on the standardised field sobriety tests (SFSTs) provides a sensitive measure of impaired driving behaviour following the consumption of THC. In a repeated measures design, 40 participants consumed cigarettes that contained either 0% THC (placebo), 1.74% THC (low dose) or 2.93% THC (high dose). For each condition, after smoking a cigarette, participants performed the SFSTs on three occasions (5, 55 and 105 min after the smoking procedure had been completed) as well as a simulated driving test on two occasions (30 and 80 min after the smoking procedure had been completed). The results revealed that driving performance was not significantly impaired 30 min after the consumption of THC but was significantly impaired 80 min after the consumption of THC in both the low and high dose conditions. The percentage of participants whose driving performance was correctly classified as either impaired or not impaired based on the SFSTs ranged between 65.8 and 76.3%, across the two THC conditions. The results suggest that performance on the SFSTs provides a moderate predictor of driving impairment following the consumption of THC and as such, the SFSTs may provide an appropriate screening tool for authorities that wish to assess the driving capabilities of individuals suspected of being under the influence of a drug other than alcohol. 相似文献
A controlled laboratory experiment is described, in principle and practice, which can be used for the of determination the rate of tissue decomposition in soil. By way of example, an experiment was conducted to determine the effect of temperature (12 degrees, 22 degrees C) on the aerobic decomposition of skeletal muscle tissue (Organic Texel x Suffolk lamb (Ovis aries)) in a sandy loam soil. Measurements of decomposition processes included muscle tissue mass loss, microbial CO2 respiration, and muscle tissue carbon (C) and nitrogen (N). Muscle tissue mass loss at 22 degrees C always was greater than at 12 degrees C (p < 0.001). Microbial respiration was greater in samples incubated at 22 degrees C for the initial 21 days of burial (p < 0.01). All buried muscle tissue samples demonstrated changes in C and N content at the end of the experiment. A significant correlation (p < 0.001) was demonstrated between the loss of muscle tissue-derived C (Ct) and microbially-respired C (Cm) demonstrating CO2 respiration may be used to predict mass loss and hence biodegradation. In this experiment Q10 (12 degrees C-22 degrees C) = 2.0. This method is recommended as a useful tool in determing the effect of environmental variables on the rate of decomposition of various tissues and associated materials. 相似文献