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71.
72.
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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Despite numerous instrumental achievements, canines are still considered the most effective field method for explosive detection. However, due to strict explosive regulations and safety requirements, it can be a challenge for agencies with "bomb dogs" to train using neat explosive materials. This establishes a need for non-explosive canine training aids with the same volatile component profiles as the explosives that they represent. In order to compare mimic materials to their explosive counterparts, a technique must be established that not only allows for identification of volatile compounds but also can monitor changes in the headspace profile over time with respect to time and temperature. The Automated Training Aid Simulation using SPME (or ATASS) was developed for that purpose. As described, ATASS was used to observe changes in the volatile profile of three explosives (Composition C-4, 2,4-dinitrotoluene (DNT), and triacetone triperoxide (TATP)) and respective prototype training materials (0.1% by mass C-4, 1% by mass 2,4-DNT, and 1% by mass TATP). Samples were prepared in vials and metal tins within a gallon (≈ 3785 mL) paint can to simulate common field techniques for canine training. Monitoring these materials in real time provides a better understanding of the major volatile components present and how the relative abundances of these components can change over time. The results presented indicate that ATASS successfully allows for a sufficient comparison between explosive and non-explosive training materials.  相似文献   
75.
What is the role of stipends as an institutional facilitator in volunteer civic service? By examining the relationship of stipend receipt to volunteer diversity, time commitment, and perceived benefits from a longitudinal study of older adults serving in Experience Corps, this article assesses stipend status relative to volunteer sociodemographic characteristics, motivations, intensity and duration of time served, and volunteers’ self‐reported benefits. The findings underscore how stipends may promote participant diversity. In particular, stipended older adult volunteers serve for longer periods of time, but their motivations for serving do not differ. Stipended volunteers report higher perceived benefits than nonstipended volunteers. The results suggest that stipends may leverage wider inclusion, increase retention, and contribute to other benefits, but additional research is needed using more controlled and comparative designs.  相似文献   
76.
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   
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Abstract

Other-deception and self-deception are important variables to consider when conducting a forensic psychological evaluation. The main aim of the present study was to investigate the effects of setting on other-deception and self-deception scores. It was hypothesised that patients at a maximum security hospital (Broadmoor) would score lower on an other-deception questionnaire than similar patients at a medium secure unit (Denis Hill Unit). All the patients completed the other-deception (ODQ) and self-deception (SDQ) questionnaires of Sackeim and Gur (1979) on admission to the two security hospitals. The Broadmoor patients (N = 46) obtained significantly lower ODQ score than the Denis Hill Unit (N = 52) patients, after controlling for differences in ethnic background and diagnosis among the two populations. No significant difference in setting was found for the SDQ score. The ODQ and SDQ scores were significantly associated with the type of diagnosis and the ethnic background of the patient, with patients diagnosed as mentally ill scoring higher than those with a diagnosis of personality disorder, and ethnic minority patients scoring higher than Caucasian patients.  相似文献   
79.
In developing countries in particular, services are often delivered through unorthodox organisational arrangements that cannot simply be dismissed as relics of ‘traditional’ institutions, or as incomplete modern organisations. Some have emerged recently, and represent institutional adaptations to specific political and logistical circumstances. We need to expand the range of organisational categories that are considered worthy of study and develop a better understanding of the strengths and weaknesses of unorthodox arrangements. The concept of institutionalised co-production provides a useful point of entry. Institutionalised co-production is defined as: the provision of public services (broadly defined, to include regulation) through a regular long-term relationship between state agencies and organised groups of citizens, where both make substantial resource contributions. We explain some varieties of institutionalised co-production arrangements; explore why they appear to be relatively so widespread in poor countries; and relate the concept to broader ideas about public organisation.  相似文献   
80.
Joe Moore 《亚洲研究》2013,45(3):35-47
Abstract

Robert Cole points out in his introduction to Japanese Blue Collar that there are two dominant but conflicting views of the social relations of production in the Japanese economy, views which Cole conveniently sums up under the rubrics of “uniqueness” and “convergence.”  相似文献   
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