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51.
While canines are most commonly trained to detect traditional explosives, such as nitroaromatics and smokeless powders, homemade explosives (HMEs), such as fuel–oxidizer mixtures, are arguably a greater threat. As such, it is imperative that canines are sufficiently trained in the detection of such HMEs. The training aid delivery device (TADD) is a primary containment device that has been used to house HMEs and HME components for canine detection training purposes. This research assesses the odor release from HME components, ammonium nitrate (AN), urea nitrate (UN), and potassium chlorate (PC), housed in TADDs. Canine odor recognition tests (ORTs) were used with analytical data to determine the detectability of TADDs containing AN, UN, or PC. Headspace analysis by gas chromatography/mass spectrometry (GC/MS) with solid-phase microextraction (SPME) or online cryotrapping were used to measure ammonia or chlorine, as well as other unwanted odorants, emanating from bulk AN, UN, and PC in TADDs over 28 weeks. The analytical data showed variation in the amount of ammonia and chlorine over time, with ammonia from AN and UN decreasing slowly over time and the abundance of chlorine from PC TADDs dependent on the frequency of exposure to ambient air. Even with these variations in odor abundance, canines previously trained to detect bulk explosive HME components were able to detect all three targets in glass and plastic TADDs for at least 18 months after loading. Detection proficiency ranged from 64% to 100% and was not found to be dependent on either age of material.  相似文献   
52.
The storage and use of explosives is regulated at the state and federal level, with a particular focus on physical security and rigorous accounting of the explosive inventory. For those working with explosives for the training and testing of explosive-detecting canines, cross-contamination is an important concern. Hence, explosives intended for use with canine teams must be placed into secondary storage containers that are new, clean, and airtight. A variety of containers meet these requirements and include screw-top glass jars (e.g., mason jars). However, an additional need from the explosive-detecting canine community is secondary containers that can also be used as training aids whereby the volatiles emitted by explosives are emitted in a predictable and stable manner. Currently, a generally accepted method for the storage of explosives and controlled emission of explosive vapor for canine detection does not exist. Ideally, such containers should allow odor to escape from the training aid but block external contaminates such as particulates or other volatiles. One method in use places the explosive inside a permeable cotton bag when in use for training and then stores the cotton bag inside an impermeable nylon bag for long-term storage. This paper describes the testing of an odor permeable membrane device (OPMD) as a new way to store and deploy training aids. We measured the evaporation rate and flux of various liquid explosives and volatile compounds that have been identified in the headspace of actual explosives. OPMDs were used in addition to traditional storage containers to monitor the contamination and degradation of 14 explosives used as canine training aids. Explosives were stored individually using traditional storage bags or inside an OPMD at two locations, one of which actively used the training aids. Samples from each storage type at both locations were collected at 0, 3, 6, and 9 months and analyzed using Fourier Transform Infrared (FTIR) Spectroscopy and Gas Chromatography–Mass Spectrometry (GC–MS) with Solid-Phase Microextraction (SPME). FTIR analyses showed no signs of degradation. GC–MS identified cross-contamination from ethylene glycol dinitrate (EGDN) and/or 2,3-dimethyl-2,3-dinitrobutane (DMNB) across almost all samples regardless of storage condition. The contamination was found to be higher among training aids that were stored in traditional ways and that were in active use by canine teams.  相似文献   
53.
This work presents a data survey regarding the qualitative chemical analysis of drugs seized by the Police in the state of Minas Gerais between July 2017 and June 2022, including an evaluation of labeling of 265 samples of anabolic androgenic steroids (AAS) seized in 2020. The Active Pharmaceutical Ingredients (API) present in the samples were identified through chemical analysis and classified by system Anatomical Therapeutic Chemical (ATC) methods. Analysis of the labeling information for 265 samples of AAS followed the guidance of legislation RDC 71 (2009) from ANVISA. For this study 6355 seized pharmaceuticals underwent qualitative chemical analysis that corresponded to 7739 APIs successfully identified and classified. Among the components studied AAS, psychostimulants, anesthetics, and analgesics were the most commonly examined. AAS seized and tested increased by over 100% and for the majority of the samples analyzed were found to not match the labeling on the packaging. In the meantime, anti-obesity drugs presented a prominent increase of 400% from 2020/1 to 2021/2, during covid-19 quarantine. Seized pharmaceuticals and tests can support information in the planning of public health and safety policies.  相似文献   
54.
Human hairs are one of the most commonly encountered items of trace evidence. Currently, conventional methods for hair analysis include microscopic comparison and DNA analysis (nuclear and mitochondrial). Each approach has its own drawbacks. Hair proteins are stable and offer an alternative to DNA testing, as demonstrated with proteomics for distinguishing humans. However, proteomics is complicated and requires identifying peptides to remain intact following harsh sample preparation methods. Alternatively, the actual amino acid content of a hair sample may also offer important identifying information and actually requires proteins and peptides to be broken down completely rather than remaining intact. This study evaluated the discriminating power of using hair amino acid ratios to differentiate hair samples from 10 unrelated individuals with dark colored hair. Hair proteins were digested, derivatized, and analyzed using gas chromatography–mass spectrometry. Amino acid ratios were calculated for each individual and comparisons using ANOVA and post-hoc pairwise t-test with Bonferroni correction were made with amino acid ratios for individuals. Overall, out of the 45 possible pairwise comparisons between all hair samples, 38 (84%) were differentiable. Out of the 36 possible pairwise comparisons between brown haired individuals, 32 (89%) were considered differentiable using univariate statistics. Multivariate statistics were also attempted but, overall, univariate models were sufficient for exclusionary purposes. These results indicate that amino acid ratio analysis can potentially be used as an exclusionary method using hair if DNA analysis cannot be performed, or to corroborate conclusions made following microscopic analysis.  相似文献   
55.
Federal governments are increasingly employing empirical measures of lower‐level government performance to ensure that provincial and local jurisdictions pursue national policy goals. We call this burgeoning phenomenon “performance federalism” and argue that it can distort democratic accountability in lower‐level elections. We estimate the impact of a widely publicized federal indicator of local school district performance—one that we show does not allow voters to draw valid inferences about the quality of local educational institutions—on voter support for school tax levies in a U.S. state uniquely appropriate for this analysis. The results indicate that a signal of poor district performance increases the probability of levy failure, a substantively large and robust effect that disproportionately affects impoverished communities. The analysis employs a number of identification strategies and tests for multiple behavioral mechanisms to support the causal interpretation of these findings.  相似文献   
56.
In the public administration literature, research on performance measurement has recognized the important place of cost accounting in relation to performance. Extant research, such as the North Carolina Benchmarking Program, supports the proposition that performance and cost accounting naturally complement each other to increase trust in performance information and increase organizational learning. Other statements about cost accounting suggest that performance measurement and cost accounting compete as systems of control. This research uses general cost accounting plan information and performance measurements in the budgets of large U.S. cities to test the competing and complementary control relationship at the organizational and service levels. It finds that performance measurements and cost accounting are negatively related at the service level, which supports the competing control system hypothesis. At the organizational level, performance and cost accounting are positively related but not at traditional levels of significance.  相似文献   
57.
58.
This article examines the evolution of transnational Zapatista solidarity networks. Although scholars have described an emerging "mutuality" between the Zapatista movement and its allies at the level of international framing, this article considers how the Zapatistas forged this mutuality on the ground, through active redefinition of alliances with Northern supporters. It argues that the Zapatistas delimited who was included in their solidarity networks, set new terms for partnerships, and redefined legitimacy in their transnational alliances. In so doing, they asserted their autonomy from donors. They also fostered discourses and practices of mutual solidarity and Southern leadership, shifting the balance of power between North and South. The case both illuminates the possibilities for Southern movements to challenge Northern control from within and suggests potential pitfalls of doing so; by defying Northern NGOs' influence, the Zapatistas may have risked their long-term viability.  相似文献   
59.
60.
Creating offender typologies has become a growing interest and a potential method of improving understanding of programming needs and potential placements. Most typological research has only explored and described potential offender types. Relatively few studies have attempted to confirm the existence of created typologies or examine how offenders in each type predict important outcomes. Utilizing a large sample (N = 37,111) of reentering male offenders from Washington State Department of Corrections, we computed both an exploratory and confirmatory latent class analysis. After the confirmation of six offender types, we examined each type’s likelihood of several recidivistic outcomes. We anticipate that the described typology will assist case management, prioritizing offender needs, optimizing treatment services, and determining sequencing of multiple treatment types.  相似文献   
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