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81.
Terezie Cernosek B.S. Kevin E. Eckert M.Sc. David O. Carter Ph.D. Katelynn A. Perrault Ph.D. 《Journal of forensic sciences》2020,65(1):134-143
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
82.
Alex J. Krotulski M.S.F.S. Susan Jansen Varnum Ph.D. Barry K. Logan Ph.D. 《Journal of forensic sciences》2020,65(2):550-562
Novel psychoactive substances (NPS) are synthetic drugs that pose serious public health and safety concerns. A multitude of NPS have been identified in the United States, often implicated in forensic investigations. The most common and effective manner for identifying NPS is by use of mass spectrometry and the true utility lies within nontargeted acquisition techniques. During this study, a liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) assay was developed, validated, and implemented for forensic toxicology testing. A SCIEX TripleTOF™ 5600 + with SWATH® acquisition was used. Resulting data were compared against an extensive library database containing more than 800 compounds. The LC-QTOF-MS assay was applied to the reanalysis of biological sample extracts to discover emergent NPS. More than 3,000 sample extracts were analyzed, and more than 20 emerging NPS were detected for the first time. Among these were isopropyl-U-47700, 3,4-methylenedioxy-U-47700, fluorofuranylfentanyl, N-methyl norfentanyl, 2F-deschloroketamine, 3,4-methylenedioxy-alpha-PHP, eutylone, and N-ethyl hexedrone. 相似文献
83.
M. Alex Wagaman Jama Shelton Rebecca Carter Kado Stewart Stacey Jay Cavaliere 《Child & Youth Services》2019,40(1):43-64
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
84.
85.
Anthony L. Burrow Amanda C. O’Dell Patrick L. Hill 《Journal of youth and adolescence》2010,39(11):1265-1273
While having a purpose in life has been theorized as a developmental asset, the extent to which adolescents cultivate a meaningful
sense of direction is not well understood. In the present study, cluster analysis was used to classify adolescents by levels
of purpose exploration and commitment. The sample (N = 318; 55% female) consisted of youth aged 14–18 and was predominantly White/non-Hispanic (76.3%). Results supported four
meaningful yet distinguishable profiles of youth purpose that are largely consistent with theories on identity formation:
Achieved, Foreclosed, Uncommitted, and Diffused. Hypothesized linkages with affect and hope were established across the profiles
such that positive emotions and goal-directed thinking were most apparent among Achieved and Foreclosed youth and least apparent
among Diffused and Uncommitted youth. Overall, findings demonstrate the inherent complexity in adolescents’ engagement with
purpose and suggest a correspondence between stronger commitments to purpose and youths’ sense of personal agency and well-being. 相似文献
86.
Nicole Leeper Piquero Kristan Fox Alex R. Piquero George Capowich Paul Mazerolle 《Journal of youth and adolescence》2010,39(4):380-392
Much of the prior work on General Strain Theory (GST) has focused on how strain and negative emotions interrelate to produce
criminal—especially violent—activity. Very little research has extended GST to examine other types of non-criminal, negative
behavior, such as self-harming behaviors associated with disordered eating, a traditionally female-specific self-directed
outcome. Using a sample of 338 young adults (54% female, 95% white), this article applies GST to disordered eating by examining
how strain and negative emotions relate to this particular outcome across gender. Findings indicate that two types of strain
measures predict depressive symptoms among males and females, that inequitable strainful experiences relate to disordered
eating among females but not males, that depressive symptoms but not anger increase disordered eating for both males and females,
and that membership in Greek organizations (sororities or fraternities) is associated with disordered eating but only for
males. Implications for theory and directions for future research are highlighted. 相似文献
87.
Ellen H. O’Donnell Melissa Moreau Esteban V. Cardemil Alisha Pollastri 《Journal of youth and adolescence》2010,39(1):12-22
Research on the mechanisms by which interparental conflict (IPC) affects child depression suggests that both parenting and
children’s conflict appraisals play important roles, but few studies have explored the role of general cognitive style or
included both parenting and cognitions in the same design. Moreover, the effects of IPC on minority children are not well
understood. In this longitudinal study, parenting was examined as a mediator of the relation between increasing IPC and change
in depression. General cognitive style was included as a moderator. The combined influence of parenting and cognitions was
also explored. A racially and ethnically diverse sample of 88 fifth and sixth graders from two urban schools reported their
cognitive style, depressive symptoms, and perceptions of conflict and parenting at two time points separated by one year.
Parental warmth/rejection mediated the relation between IPC and depression, and general cognitive style acted as a moderator.
Parenting, cognitive style, and IPC did not significantly interact to predict change in depression over time. Findings indicate
that both parenting and children’s general cognitive style play a role in understanding the impact of increasing IPC on children’s
well-being. 相似文献
88.
Tobias Jung Tim Scott Huw T. O. Davies Peter Bower Diane Whalley Rosalind McNally Russell Mannion 《Public administration review》2009,69(6):1087-1096
Organizational culture is widely considered to be one of the most significant factors in reforming and modernizing public administration and service delivery. This article documents the findings of a literature review of existing qualitative and quantitative instruments for the exploration of organizational culture. Seventy instruments are identified, of which 48 could be submitted to psychometric assessment. The majority of these are at a preliminary stage of development. The study's conclusion is that there is no ideal instrument for cultural exploration. The degree to which any measure is seen as "fit for purpose" depends on the particular reason for which it is to be used and the context within which it is to be applied. 相似文献
89.
My brand new bicycle had been stolen! Disbelief. Anger! Disappointment... I had been riding it for only a day,and was as excited as a,well,a boy with a new bike. Even though I only paid what would be the equivalent of half a tank of gas for my truck back home,I was still sorely put out. 相似文献
90.