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151.
152.
Meghan Prusinowski PhD Pedram Tavadze PhD Zachary Andrews MS Logan Lang BS Divyanjali Pulivendhan BS Cedric Neumann PhD Aldo H. Romero PhD Tatiana Trejos PhD 《Journal of forensic sciences》2024,69(2):498-514
A physical fit is an important observation that can result from the forensic analysis of trace evidence as it conveys a high degree of association between two items. However, physical fit examinations can be time-consuming, and potential bias from analysts may affect judgment. To overcome these shortcomings, a data analysis algorithm using mutual information and a decision tree has been developed to support practitioners in interpreting the evidence. We created these tools using data obtained from physical fit examinations of duct tape and textiles analyzed in previous studies, along with the reasoning behind the analysts' decisions. The relative feature importance is described by material type, enhancing the knowledge base in this field. Compared with the human analysis, the algorithms provided accuracies above 90%, with an improved rate of true positives for most duct tape subsets. Conversely, false positives were observed in high-quality scissor cut (HQ-HT-S) duct tape and textiles. As such, it is advised to use these algorithms in tandem with human analysis. Furthermore, the study evaluated the accuracy of physical fits when only partial sample lengths are available. The results of this investigation indicated that acceptable accuracies for correctly identifying true fits and non-fits occurred when at least 35% of a sample length was present. However, lower accuracies were observed for samples prone to stretching or distortion. Therefore, the models described here can provide a valuable supplementary tool but should not be the sole means of evaluating samples. 相似文献
153.
Purpose
This research is intended to inform a knowledge gap in the literature and present the first national findings related to intelligence-led policing adoption among state and local agencies. Specific practices are identified to inform scholars and practitioners regarding intelligence-led policing behaviors.Methods
Original survey research from a federally-funded project is gleaned to explore intelligence-led policing adoption through a loose-coupling theoretical perspective. Negative binomial and logistic regression models are employed to identify predictive relationships.Results
Agencies nationwide appear to be closely following the National Criminal Intelligence Sharing Plan recommendations to enhance information sharing. Consistent with the Department of Homeland Security’s Target Capabilities List is also observed. Agency size appears to have a significant effect on key organizational information sharing behaviors. The findings are tempered due to limitations in the research design.Conclusions
Local agencies appear to be tightly-coupled with the recommendations put forth in the National Criminal Intelligence Sharing Plan in their efforts to adopt intelligence-led policing. Agency size appears to enhance adoption across most dependent metrics. This research progresses the limited evidence base and progress regarding this emerging policing philosophy. 相似文献154.
Jessica Skinner PhD Natalie Langley PhD Malin Joseph MS James Herrick MSA Robert Brown BS Brian Waletzki BS Peter Goguen Dipl T Loukham Shyamsunder PhD Subramaniam Rajan PhD 《Journal of forensic sciences》2023,68(3):757-767
Forensic fractographic features of bone reliably establish crack propagation in perimortem injuries. We investigated if similar fracture surface features characterize postmortem fractures. Experimentally induced peri- and postmortem fractures were used to assess if fractographic features vary as bone elasticity decreases during the postmortem interval (PMI). Thirty-seven unembalmed, defleshed human femoral shafts from males and females aged 33–81 years were fractured at varying PMIs with a drop test frame using a three-point bending setup and recorded with a high-speed camera. Vital statistics, cause of death, PMI length, temperature, humidity, collagen percentage, water loss, fracture energy, and fractography scores were recorded for each sample. Results showed that fractographic features associated with perimortem fractures were expressed in PMIs up to 40,600 accumulated degree hours (ADH), or 60 warm weather days. Hackle was the most consistently expressed feature, occurring in all fractures regardless of ADH. The most variable characteristics were wake features (78.4%) and arrest ridges (70.3%). Collagen percentage did not correlate strongly with ADH (r = −0.04, p = 0.81); however, there was a strong significant correlation between ADH and water loss (r = 0.74, p < 0.001). Multinomial logistic regression showed no association between fractographic feature expression and ADH or collagen percentage. In conclusion, forensic fractographic features reliably determine initiation and directionality of crack propagation in experimentally induced PMIs up to 40,600 ADH, demonstrating the utility of this method into the recent postmortem interval. This expression of reliable fractographic features throughout the early PMI intimates these characteristics may not be useful standalone features for discerning peri- versus postmortem fractures. 相似文献
155.
Scott Fullwiler 《Public Budgeting & Finance》2020,40(3):72-94
Modern Monetary Theory (MMT) argues that the interest rate on the national debt for a monetary sovereign is a policy variable, not subject to whether bond markets “accept” or “reject” it. This paper defines measures of the components of the standard analysis of fiscal sustainability. It then methodically describes the Federal Reserve's operations relevant for understanding why interest rates on government debt in the United States have been and continue to be driven by monetary policy. A corollary that emerges—“printing money,” as economists usually understand it—is not applicable and has never been advocated by MMT. 相似文献
156.
The complexity of the modern information ecosystem raises many questions for public organizations. In the context of emergency management, information (such as warning messages) is communicated not only from a source of authority to the public but also between members of the public. The authors use a series of storms that affected Oklahoma in the spring of 2016 to test propositions related to how information about tornado warnings reached the public and who received and shared information about the storm, as well as to identify how gender and age mediate the influence that exposure to an extreme weather event has on the sharing of this information. Overall, the authors find that reported exposure to a tornado increases information sharing through a variety of media and technology. The effect of the tornado erases the otherwise present gender gap in sharing information, while it has little effect on the media platforms that are most popular among older respondents. 相似文献
157.
David Scott 《圆桌》2018,107(3):307-316
This article considers how far the UK is returning to an ‘East of Suez’ role in the Indian Ocean. A threefold structure is taken based on past, current and future aspects of this role. The first section (‘past’) considers the Indian Ocean as a British Lake and the announced withdrawal from East of Suez that was announced in the early 1970s. The second section (‘present’) looks at the various bases, facilities and partnerships that the UK has around and across the Indian Ocean with Bahrain, Oman, Gulf of Aden, Somaliland, Diego Garcia (and the United States), India, Malaysia and Singapore (including the Five Power Defence Agreements), Australia and China. The third section (‘future’) considers likely post-BREXIT decisions facing the UK in the Indian Ocean with regard to its projected naval assets and political choices across the region. It finds there is some substance behind the rhetoric on a British return to the area. 相似文献
158.
The Supplemental Security Income (SSI) program, established by the Social Security Amendments of 1972 (Public Law 92-603), was designed to provide cash assistance to needy aged, blind, and disabled citizens, and noncitizens lawfully admitted for permanent residence or permanently residing under color of law. Since then, this means-tested program has undergone many legislative changes that affect the eligibility status of noncitizens. This article, presented in three parts, discusses the legislative history of noncitizen eligibility, and details relevant laws enacted since the program's inception; provides current data on the trends and changes of the noncitizen population; and describes the larger population of foreign-born SSI recipients, of which the noncitizens are a part. Data on the number of SSI recipients born abroad but who had become citizens before applying for SSI payments were not previously available. Analytical data are from the Supplemental Security Record (SSR) matched to the Social Security Number Identification (Numident) file. 相似文献
159.
Evaluation of cannabinoid concentrations in products from the legal cannabis market has been fraught with uncertainty. The lack of standardized testing methodology and the susceptibility of cannabinoids to degradation under certain storage conditions complicates the efforts to assess total tetrahydrocannabinol (THC) levels across wide geographic areas. There are few peer-reviewed surveys of cannabinoid concentrations in regulated products. Those that have been done have not characterized the effects of differences in analytical methodology, sample population, and storage conditions. Viridis Laboratories, which operates two cannabis safety compliance facilities in Michigan, has analyzed over 34,000 cannabis products throughout 2021 and 2022 before the sale in the regulated market. Fifteen cannabinoids in cannabis flower, concentrates, and infused products were tested using methanolic extraction and analysis by high-performance liquid chromatography with diode-array detection. Methods were validated before use, and the flower analysis procedure was certified by the Association of Analytical Collaboration. All the samples were tested before submission for sale and therefore had not undergone prolonged storage. The results are compared with those seen in other states as well as in the illicit market. Total THC levels in cannabis flower from the regulated market are significantly higher than those seen in illicit products. The distribution of cannabinoid levels is similar in flowers intended for either the medicinal or adult-use markets, with an average potency of 18%–23% of total THC. Total THC in concentrates averages up to 82%. Other cannabinoids are observed at significant levels, mostly in products specifically formulated to contain them. These results may act as a benchmark for potency levels in the regulated market. 相似文献
160.
Richard C. Harruff MD PhD Nicole A. Yarid MD William L. Barbour BS Yang H. Martin MS 《Journal of forensic sciences》2023,68(5):1632-1642
As the overdose epidemic overwhelmed medicolegal death investigation offices and toxicology laboratories, the King County Medical Examiner's Office responded with “real-time” fatal overdose surveillance to expedite death certification and information dissemination through assembling a team including a dedicated medicolegal death investigator, an information coordinator, and student interns. In-house testing of blood, urine, and drug evidence from scenes was performed using equipment and supplies purchased for surveillance. Collaboration with state laboratories allowed validation. Applied forensic epidemiology accelerated data dissemination. From 2010 to 2022, the epidemic claimed 5815 lives in King County; the last 4 years accounted for 47% of those deaths. After initiating the surveillance project, in-house testing was performed on blood from 2836 decedents, urine from 2807, and 4238 drug evidence items from 1775 death scenes. Time to complete death certificates decreased from weeks to months to hours to days. Overdose-specific information was distributed weekly to a network of law enforcement and public health agencies. As the surveillance project tracked the epidemic, fentanyl and methamphetamine became dominant and were associated with other indicators of social deterioration. In 2022, fentanyl was involved in 68% of 1021 overdose deaths. Homeless deaths increased sixfold; in 2022, 67% of 311 homeless deaths were due to overdose; fentanyl was involved in 49% and methamphetamine in 44%. Homicides increased 250%; in 2021, methamphetamine was positive in 35% of 149 homicides. The results are relevant to the value of rapid surveillance, its impact on standard operations, selection of cases requiring autopsy, and collaboration with other agencies in overdose prevention. 相似文献