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151.
Microbial communities have potential evidential utility for forensic applications. However, bioinformatic analysis of high-throughput sequencing data varies widely among laboratories. These differences can potentially affect microbial community composition and downstream analyses. To illustrate the importance of standardizing methodology, we compared analyses of postmortem microbiome samples using several bioinformatic pipelines, varying minimum library size or minimum number of sequences per sample, and sample size. Using the same input sequence data, we found that three open-source bioinformatic pipelines, MG-RAST, mothur, and QIIME2, had significant differences in relative abundance, alpha-diversity, and beta-diversity, despite the same input data. Increasing minimum library size and sample size increased the number of low-abundant and infrequent taxa detected. Our results show that bioinformatic pipeline and parameter choice affect results in important ways. Given the growing potential application of forensic microbiology to the criminal justice system, continued research on standardizing computational methodology will be important for downstream applications.  相似文献   
152.
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   
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154.
Journal of Youth and Adolescence - Adolescence tends to be characterized by a temporary peak in delinquent behavior, and friends in particular play a key role in the initiation and the development...  相似文献   
155.
Few studies have examined risk factors of childhood and early adolescent depressive symptomatology trajectories. This study examined self-report depressive symptomatology across a 6-year time period from 2nd to 8th grade to identify latent groups of individuals with similar patterns of depressive phenomena in a sample of 951 children (440 girls, 511 boys). Analyses, using semiparametric group modeling (SGM), identified 5 trajectory groups for girls and boys: low depressed stables, low depressed risers, mildly depressed stables, moderately depressed changers, and moderately depressed risers. Individual risk factors, with the exception of shy/withdrawn behavior, were significantly different across trajectory group membership for boys and girls, as was low-income status for boys. Boys in the low depressed and mildly depressed stable trajectory groups had significantly higher levels of antisocial behavior, attention problems, and lower social competency compared to girls in similar groups. These results suggest that universal prevention programs implemented in early elementary school that target selected risk factors may be helpful in reducing future adolescent mental health problems, specifically depressive symptomatology.  相似文献   
156.
The current study examined concurrent and longitudinal predictors of early adolescents’ involvement in Internet aggression. Cross-sectional results (N = 330; 57% female) showed that the likelihood of reporting Internet aggression was higher among youth who spent more time using Internet-based technologies to communicate with friends and who were themselves targets of Internet aggression. Offline relational aggression and beliefs supportive of relational and physical aggression also predicted concurrent involvement in Internet aggression. We used longitudinal data (N = 150; 51% female) to distinguish between youth who were aggressive in traditional contexts only (i.e., school) from those who were aggressive both online and offline. These results indicated that youth who were aggressive both online and offline were older at the initial assessment, were targets of Internet aggression, and held beliefs more supportive of relational aggression than youth who were aggressive offline only. Implications and directions for future research are discussed.  相似文献   
157.
The National Oceanic and Atmospheric Administration instituted a Planning, Programming, Budgeting, and Execution System (PPBES) in 2002. As supplemented by matrix management, PPBES was appealing as an effort to rationalize the performance of an agency with an especially high degree of functional overlap among its component parts. Although PPBES has had some salutary effects, the agency's experience to date consistent with accounts of the difficulties that led to the abandonment of program budgeting by the civilian bureaucracy almost 40 years ago. As such, it speaks to the limits of performance assessment as a means of reallocating resources and responsibilities across organizational boundaries.  相似文献   
158.
This article takes a state's eye view of trends towards a more centralised system of governance in Australia. It argues that while globalisation strengthens the roles of national governments it also provides less noticed public policy and management opportunities for sub-national governments. The article shows how state governments in Australia can use high-level policy proposals to reinforce their continuing relevance as key members of a federal system of government. It proposes that skilful deployment of policy ideas and analyses can enable the states to sustain alternative national agendas despite hostility or lack of interest by the federal government. In conclusion, the article examines the implications for federal-state relations under the Rudd government. It suggests that the elements for productive reform agendas are present but that bringing them together will require considerable effort.  相似文献   
159.
It is understandable that Iran’s December 2006 hosting of an international conference casting doubts on the historicity of the Holocaust would raise questions about treatments of the Shoah elsewhere in the Third World. In fact, indigenization the Holocaust—the manifold ways in which serious scholars, activists, and writers from Asia, Africa, and Latin America have come to incorporate the Holocaust in their intellectual work—has been positive overall. Within the framework of intellectual globalization, much of the Third World intelligentsia has come to include this most Western of human rights violations within the framework of their own cultures and histories. Although some of the indigenization of the Holocaust is political and instrumental, the deviant variant expressed at the Tehran Holocaust conference is atypical. Governmental respect for the memory of victims of genocide should be considered as an emerging human right.  相似文献   
160.
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