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41.
Yi‐Hong Liao BS Jae‐Sang Hyun PhD Michael Feller MS Tyler Bell PhD Ian Bortins BS James Wolfe MS David Baldwin PhD Song Zhang PhD 《Journal of forensic sciences》2021,66(1):112-128
The forensic science community raised the need for improved evidence recognition, collection, and visualization analytical instrumentation for field and laboratory use. While the 3D optical techniques for imaging static objects have been extensively studied, there is still a major gap between current knowledge and collecting high‐quality footwear and tire impression evidence. Among optical means for 3D imaging, digital fringe projection (DFP) techniques reconstruct 3D shape from phase information, achieving camera‐pixel spatial resolution. This paper presents a high‐resolution 3D imaging technology using DFP techniques dedicated to footwear and tire impression capture. We developed fully automated software algorithms and a graphical user interface (GUI) that allow anyone without training to operate for high‐quality 3D data capture. We performed accuracy evaluations and comparisons comparing with the commercial high‐end 3D scanner and carried out qualitative tests for various impressions comparing with the current practices. Overall, our technology achieves similar levels of accuracy and resolution with a high‐end commercially available 3D scanner, while having the merits of being (1) more affordable; (2) much easier to operate; and (3) more robust. Compared with the current practice of casting, our technology demonstrates its superiority because it (1) is non‐destructive; (2) collects more evidence detail than casts, especially when an impression is fragile; (3) requires less time and money to collect each piece of evidence; and (4) results in a digital file that can easily be shared with other examiners. 相似文献
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Darrell O. Ricke Ph.D. Philip Fremont‐Smith M.S. James Watkins B.S. Sara Stankiewicz M.S. Tara Boettcher B.S. Eric Schwoebel Ph.D. 《Journal of forensic sciences》2019,64(5):1468-1474
High‐throughput sequencing (HTS) of large panels of single nucleotide polymorphisms (SNPs) provides an alternative or complimentary approach to short tandem repeats (STRs) panels for the analysis of complex DNA mixture forensic samples. For STRs, methods to estimate individual contribution concentrations compare capillary electrophoresis peak heights, peak areas, or HTS allele read counts within a mixture. This article introduces three approaches (mean, median, and slope methods) for estimating individual DNA contributions to forensic mixtures for HTS/massively parallel sequencing (MPS) SNP panels. For SNPs, the major:minor allele ratios or counts, unique to each contributor, were compared to estimate contributor proportion within the mixture using the mean, median, and slope intercept for these alleles. The estimates for these three methods were typically within 5% of planned experimental contributions for defined mixtures. 相似文献
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Andrea Ribeiro Hoffmann 《Democratization》2019,26(5):815-831
ABSTRACTThis article analyses negotiations on democracy promotion by looking at the case of the Inter-American Democratic Charter. It argues that Venezuela contested the concept of representative democracy during the Charter negotiations, advancing the notion of “participatory and protagonist democracy” and that, even if it was unsuccessful in its demands, the country contributed to deepening the debate on the concept of democracy, on which there is far from worldwide consensus. The article suggests that the main drivers of the negotiation process and the final agreement were domestic political changes in Venezuela, specific features of the negotiations, and the structural position of Venezuela in the field of democracy promotion in the global and regional contexts, which were, at the time, favourable to a compromising attitude to conclusion of the Charter, even if not to the concept of democracy. 相似文献
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Noelia I. Zanetti DB Andrea Costantino DChem Natalia Lazzarini BSChem Adriana A. Ferrero DB Néstor D. Centeno DB 《Journal of forensic sciences》2021,66(1):245-254
Fluoxetine is a selective serotonin reuptake inhibitor, commonly used for the treatment of a variety of psychopathological conditions. As such, fluoxetine may be expected to appear in clinical and forensic cases. Dermestes maculatus De Geer (Coleoptera: Dermestidae) has been recognized as a relevant component of the insect fauna associated with decomposing human and animal remains. Experiments were conducted to study the effect of fluoxetine on developing D. maculatus using two‐drug administration models: a non‐living animal model (pork muscle) and a living one (Sus scrofa L. pigs). We assessed the duration of immature stages and total life cycle, as well as morphological parameters (body length, cephalic width, and weight). The effect of fluoxetine was studied at an overdose concentration: In the non‐living animal model the drug was mixed with macerated pork muscle (2000 mg/kg) and in the living animal model, pigs were given the drug orally (833 mg/kg). A control was used for each model. Daily observations were performed from the beginning to the end of the experiments. GC‐MS was used for drug detection and quantification. There were no statistically significant differences in the duration of immature stages, life cycle, larval mortality, morphological parameters, or sex ratio, between treatment and control, regardless of the drug administration model. Given that fluoxetine had no detectable effect on the development of D. maculatus, detection of this drug in forensic situations would not compromise the accuracy of PMI estimations. 相似文献
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Anna Arabindan‐Kesson 《Women's history review》2013,22(3):501-503
Abstract In an effort to popularise the gas stove, boost sales and minimize the genuine and perceived dangers of using this volatile domestic appliance, late Victorian gas managers and stove manufacturers employed female cookery teachers to perform public demonstrations at trade exhibitions throughout the country. Eventually, these women comprised a special department of gas sales, calling directly on customers in their homes to offer personal instruction in the proper use and care of gas stoves. Part social workers, part salesgirls, the ‘lady demons’, short for lady demonstrators, moved between the traditionally gendered separate spheres of work and home, consciously constructing a professional image that reconciled the social tensions of this new occupation. They offer an early example of women's entrance into the corporate business world, the feminisation of consumption, and the combination of customer service with social welfare. 相似文献