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51.
Gang membership is believed to impede success in the legitimate economic market while simultaneously supporting success in the illegal market. We extend the study of the economic effects of gang membership by using a within‐ and between‐individual analytic design, decomposing gang membership into multiple statuses (i.e., entering a gang, continuously in a gang, leaving a gang, and inactive gang membership), examining legal and illegal earnings simultaneously, and accounting for factors endogenous to gang membership that may contribute to economic achievement. By using panel data from 1,213 individuals who participated in the Pathways to Desistance Study to conduct a multilevel path analysis, we find that active gang membership status is unrelated to legal earnings. Alternatively, entering a gang is associated with increased illegal earnings, attributable to changes in delinquent peers and drug use, whereas leaving a gang has a direct relationship with decreased illegal earnings. Our results indicate that the positive economic effect of gang membership (i.e., illegal earnings and total earnings) is short‐lived and that, on balance, the sum of the gang membership experience does not “pay” in terms of overall earnings. 相似文献
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53.
Identification of Eight Synthetic Cannabinoids,Including 5F‐AKB48 in Seized Herbal Products Using DART‐TOF‐MS and LC‐QTOF‐MS as Nontargeted Screening Methods 下载免费PDF全文
Katherine N. Moore M.S. Demetra Garvin Pharm.D. Brian F. Thomas Ph.D. Megan Grabenauer Ph.D. 《Journal of forensic sciences》2017,62(5):1151-1158
Synthetic cannabinoids are sprayed onto plant material and smoked for their marijuana‐like effects. Clandestine manufacturers modify synthetic cannabinoid structures by creating closely related analogs. Forensic laboratories are tasked with detection of these analog compounds, but targeted analytical methods are often thwarted by the structural modifications. Here, direct analysis in real time coupled to accurate mass time‐of‐flight mass spectrometry (DART‐TOF‐MS) in combination with liquid chromatography quadruple time‐of‐flight mass spectrometry (LC‐QTOF‐MS) are presented as a screening and nontargeted confirmation method, respectively. Methanol extracts of herbal material were run using both methods. Spectral data from four different herbal products were evaluated by comparing fragmentation pattern, accurate mass and retention time to available reference standards. JWH‐018, JWH‐019, AM2201, JWH‐122, 5F‐AKB48, AKB48‐N‐(4‐pentenyl) analog, UR144, and XLR11 were identified in the products. Results demonstrate that DART‐TOF‐MS affords a useful approach for rapid screening of herbal products for the presence and identification of synthetic cannabinoids. 相似文献
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Mahfouz M Badawi A Merkl B Fatah EE Pritchard E Kesler K Moore M Jantz R Jantz L 《Forensic science international》2007,173(2-3):161-170
Sex determination is one of the essential steps in personal identification of an individual from skeletal remains. Most elements of the skeleton have been subjected to discriminant function analysis for sex estimation, but little work has been done in terms of the patella. This paper proposes a new sex determination method from the patella using a novel automated feature extraction technique. A dataset of 228 patellae (95 females and 133 males) was amassed from the William M. Bass Donated Skeletal Collection from the University of Tennessee and was subjected to noninvasive high resolution computed tomography (CT). After the CT data were segmented, a set of features was automatically extracted, normalized, and ranked. The segmentation process with surface smoothing minimizes the noise from enthesophytes and ultimately allows our methods to distinguish variations in patellar morphology. These features include geometric features, moments, principal axes, and principal components. A feature vector of dimension 45 for each subject was then constructed. A set of statistical and supervised neural network classification methods were used to classify the sex of the patellar feature vectors. Nonlinear classifiers such as neural networks have been used in previous research to analyze several medical diagnosis problems, including quantitative tissue characterization and automated chromosome classification. In this paper, different classification methods were compared. Classification success ranged from 83.77% average classification rate using labels from a Fuzzy C-Means (FCM) clustering step, to 90.3% for linear discriminant classification (LDC). We obtained results of 96.02% and 93.51% training and testing classification rates, respectively, using feed-forward backpropagation neural networks (NN). These promising results using newly developed features and the application of nonlinear classifiers encourage the usage of these methods in forensic anthropology for identifying the sex of an individual from incomplete skeletons retaining at least one patella. 相似文献
56.
Lisa A. Goodman Kristie A. Thomas Nkiru Nnawulezi Carrie Lippy Josephine V. Serrata Susan Ghanbarpour Cris Sullivan Megan H. Bair-Merritt 《Journal of family violence》2018,33(2):103-107
In the absence of ongoing involvement in the communities that are the subjects of research, even well-intentioned researchers can develop questions that are not relevant to community needs, employ methods that hurt community members, or disseminate findings in ways that are inaccessible to those most affected. Recognizing these harms, a growing number of domestic violence (DV) researchers have embraced community-based participatory research (CBPR), an approach in which researchers and community members share power at every level of the research process, co-creating knowledge that can be applied to enhance community well-being. Despite growing interest in this approach, however, there are insufficient opportunities for interested researchers to learn how to actually engage in it, especially in the DV context. To remedy this gap, the authors of this paper collaborated to develop an online toolkit for emerging researchers interested in CPBR. This brief report frames the need for CBPR in DV research using short vignettes that come from our own research experience; introduces Power Through Partnerships: A CBPR Toolkit for Domestic Violence Researchers; and presents recommendations for developing, promoting, and disseminating future CBPR research. We chose to announce the development and availability of this toolkit in an academic journal in order to highlight its scholarly and practical relevance for researcher audiences who might be less familiar with the CBPR approach. 相似文献
57.
Plastics including adhesive tapes, cable ties, and packaging are common evidence types encountered in forensic investigations and casework. Traditional examination techniques such as Fourier Transform Infrared (FTIR) spectroscopy lack specificity and are unable to discern differences within the same polymer structures leaving the analyst with a generic identification. High quality manufacturing methods further amplify the limitations in detecting variability between samples. Isotope Ratio Mass Spectrometry (IRMS) has been shown to be a valuable technique in further discriminating plastics. Discrimination is achieved by analysing the relative abundances of stable isotopes within a sample, with differences detected in isotope ratios possibly attributed to the source of raw materials and fractionation during the manufacturing process. A survey of cling wraps and re-sealable zipper storage bags collected in the Australian Capital Territory was undertaken to assess the variability in carbon and hydrogen isotope ratios of different brands and samples. The results of this research are discussed, particularly with respect to within and between brand trends, and a case study is presented as an example of the value of including IRMS in a casework context. 相似文献
58.
St John Simpson 《亚洲事务》2013,44(1):98-106
A curtain-raiser by the curator of the Exhibition of Antiquities from Afghanistan, which opens at the British Museum on 3 March 2011. The exhibits come from the National Museum in Kabul and show the richness and extent of trade in ancient times through and with Afghanistan. They are from excavations at a number of sites, including Begram, Tilla Tepe and Ai Khanum. 相似文献
59.
Megan Pickup 《Third world quarterly》2013,34(10):1941-1961
I focus on evaluating Brazilian development and humanitarian cooperation in Haiti to answer how emerging providers such as Brazil are contributing to global development through cooperation. The paper establishes criteria for evaluation, arguing that global standards for aid effectiveness need to be expanded. I argue that when assessed on ownership, efficiency and sustainability, cooperation holds several advantages and limits, such as misplaced assumptions that Brazil’s approach is appropriate elsewhere. The discussion is rooted in the context of Haiti in order to underline how outcomes are not pre-determined, but rather depend on the model’s interaction with the partner context. 相似文献
60.
Brad Simpson 《亚洲研究》2013,45(3):469-475
The Bush administration answered the terror attacks of September 11, 2001, with what it called the “global war on terror,” first the assault on and invasion of Afghanistan and then the invasion and occupation of Iraq. More and more Americans joined the opposition to the Iraq war, but for some, Afghanistan remained “the good war.” But was the war on Afghanistan ever a “good war”? The authors of Ending the US War in Afghanistan (Olive Branch Press, 2010) address these and other frequently raised questions in an easy-to-read style. The chapter reproduced here, “The War in Afghanistan Goes Global,” is one of six chapters in the pocket-sized book. Other chapters are “The USWar in Afghanistan,” “The US Invasion of Afghanistan,” “The US and Other Players in Afghanistan,” “The Impact of theWar,” and “Ending the War.” 相似文献