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61.
Accurate age estimates of immature necrophagous insects associated with a human or animal body can provide evidence of how long the body has been dead. These estimates are based on species-specific details of the insects’ aging processes, and therefore require accurate species identification and developmental stage estimation. Many professionals who produce or use identified organisms as forensic evidence have little training in taxonomy or metrology, and appreciate the availability of formalized principles and standards for biological identification. Taxonomic identifications are usually most readily and economically made using categorical and qualitative morphological characters, but it may be necessary to use less convenient and potentially more ambiguous characters that are continuous and quantitative if two candidate species are closely related, or if identifying developmental stages within a species. Characters should be selected by criteria such as taxonomic specificity and metrological repeatability and relative error. We propose such a hierarchical framework, critique various measurements of immature insects, and suggest some standard approaches to determine the reliability of organismal identifications and measurements in estimating postmortem intervals. Relevant criteria for good characters include high repeatability (including low scope for ambiguity or parallax effects), pronounced discreteness, and small relative error in measurements. These same principles apply to individuation of unique objects in general.
Key points
- Metrological rigour can increase in forensic entomology by selecting measurements based on their metrological qualities.
- Selection of high-quality features for morphological identification of organisms should consider these criteria: (1) pronounced discreteness of features (minimising group overlap or maximizing interval); (2) high repeatability of assessment (such as symmetrical width rather than asymmetrical length); (3) small relative error in measurement (selecting the physically largest continuous rigid feature for measurement).
- These metrological principles also apply to individuation of unique objects in general.
62.
Mark Alan Hughes 《Journal of policy analysis and management》1996,15(4):562-571
The consequences of administering welfare-to-work programs through county-level agencies may be the most important issue omitted from current discussions of welfare reform. An administrative geography of county welfare agencies fragments metropolitan labor markets, consigning central county residents to job-poor areas and isolating them from job-rich suburban counties. This paper illustrates this effect by mapping employment/population shifts and administrative boundaries in metropolitan Milwaukee. The paper ends with the suggestion that county agencies be allowed to play variable rather than fixed functional roles in a labor exchange process that must now accommodate a metropolitan scale. 相似文献
63.
Yang Panpan Schlomer Gabriel L. Lippold Melissa A. Feinberg Mark E. 《Journal of youth and adolescence》2021,50(8):1564-1581
Journal of Youth and Adolescence - Little is known about the developmental course of informant discrepancies in adolescent aggressive behavior problems, though whether aggression increases or... 相似文献
64.
A Pretext for Regression? The Gendered Institutional Response to COVID-19 in the Country of Football
This article considers the gendered institutional response to COVID-19 in Brazilian football. It is argued that the asymmetries of power which shaped policy are rooted in the historical marginalisation of women's sports in the country along with socially constructed notions of hegemonic masculinity. The COVID-19 pandemic has served to accentuate deeply embedded social and economic inequalities and may serve as a pretext for eroding precarious gains made in recent times. 相似文献
65.
Sierra F. Kaszubinski B.Sc. Jennifer L. Pechal Ph.D. Carl J. Schmidt M.D. Heather R. Jordan Ph.D. Mark E. Benbow Ph.D. Mariah H. Meek Ph.D. 《Journal of forensic sciences》2020,65(2):513-525
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
66.
67.
Adam Lanzarotta Ph.D. Martin M. Kimani Ph.D. Michael D. Thatcher B.S. John Lynch Ph.D. Moseley Fulcher A.S. Mark R. Witkowski Ph.D. JaCinta S. Batson M.S. 《Journal of forensic sciences》2020,65(4):1274-1279
This study describes the performance of handheld Raman devices for determining whether suspect pharmaceutical tablets declared to contain controlled substances were consistent with authentic (CWA) or not consistent with authentic (NCWA) tablets using a simple, rapid, field-friendly method capable of being used by nonexperts. Twenty-five authentic products and 84 known NCWA tablets were examined using three “parent” devices for a total of 327 analyses. On average, the parent devices yielded a true pass rate of 100%, a true fail rate of 98.4%, a false pass rate of 1.6%, and a false fail rate of 0%. The methods/libraries were then transferred to 13 identical “daughter” devices, which were used to examine 10 suspect finished dosage forms in duplicate (six known NCWA tablets and four authentic tablets) for a total of 260 measurements. On average, the daughter devices had a true pass rate of 100%, a true fail rate of 95.5%, a false pass rate of 4.5%, and a false fail rate of 0.0%. These data demonstrate that the parent–daughter electronic transfer method was successful, which permits the ability to develop methods in the laboratory that can be seamlessly pushed out to field devices. The methods can then be used to (i) prioritize samples for additional testing using other more time-consuming laboratory-based techniques needed to detect and quantify active ingredients and (ii) help support the interdiction of dangerous tablets at ports of entry, thereby preventing them from reaching the supply chain. 相似文献
68.
Merrian J. Brooks DO MS Joshua Leskovac MS Mark F. Benedetto MS Elizabeth Miller MD PhD Edward P. Mulvey PhD 《Juvenile & family court journal》2020,71(4):53-62
Motivational interviewing (MI) is a communication style focused on enhancing clients’ own motivation towards change. In the justice system MI has evidence to support that it enhances communication and change behaviors in youth. As most MI training is designed for healthcare settings training and implementation of MI must be adapted to fit the juvenile justice model. This includes both rehabilitation and restorative justice. Here we describe the details that allowed one county small county in Pennsylvania to roll out MI training and initial skills review in less than 6 months. The case reviews the details of planning, trainings, and timing of activities. We then discuss what elements of those details fit into a greater implementation plan that may be applied elsewhere. Four key elements were instrumental to implementation: 1) appreciation of JPO time constraints, 2) cost containment 3) using blending to enhance JPO flexibility with MI use, and 4) policies that normalize use of MI. This outline may assist other courts in their own implementation efforts. 相似文献
69.
70.
African agriculture is often dominated by smallholder farms composed of multiple plots. In policy circles it is often assumed that fragmentation coupled with small farm size is an impediment to increasing yields and thus decreasing poverty and food insecurity. There also exists an influential literature that explores the inverse relationship between farm size and yield. While there are many studies internationally, few have been conducted in Africa. Using an Ethiopian national survey, we explore the relationship between yield, farm size and fragmentation. We find an inverse relationship between farm size and yield, and a positive association between yield and land fragmentation. 相似文献