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1.
This research demonstrates the value of laser scanning confocal microscopy (LSCM) as a research tool in osteological studies, and diagenetic studies in particular. LSCM combines properties of light and scanning electron microscopy using laser light to excite fluorophores throughout the z-axis, developing a 3-D image. Using differential staining and selecting for specific wavelengths of light, one can image targeted materials. This research is divided into two parts: visualizing bone structures such as proteins and their decompositional products and visualizing diagenesis. Part one of this study utilized pig bones as a means of testing the overall ability of LSCM to fluoresce bone. Twenty-three samples were imaged, including 13 samples from a decompositional study conducted 5 years previous, and 10 “fresh” samples collected from a commercial butcher. This part of the study determined that protein and organic components of the bone could be fluoresced and diagenetic alteration could be imaged. The second part of the study used human samples as a means of imaging and mapping diagenetic alterations. The second part of the study used 13 samples, including 4 clinical, 7 ancient, and 2 modern controls. The pig study used Basic Fuchsin and SlowFade Gold stains, while the human study used toluidine blue. Images were also taken with unstained elements. The results of the non-human study found that a fresh bone fluoresced differently than that of a 5-year subset, while the results of the human study confirmed these findings and determined that the bone diagenesis can be mapped using LSCM. 相似文献
2.
Walter E. Bruehs Nicole M. Tucker Kimberly A. Meline 《Journal of forensic sciences》2022,67(1):200-206
Often, criminal acts involving a vehicle are caught on digital video surveillance systems. While potentially useful for an investigation, the recording conditions are typically less than optimal for the extraction of key information for the identification of the perpetrator, such as a license plate. Providing the make, model and year of a questioned vehicle is a common request for examiners, to narrow the field of potential suspect vehicles. This study seeks to compare the performance of a nonpeer-reviewed make, model, and year determination between two separate groups, specifically, trained forensic image examiners and nontrained individuals. Results show that even with varied image capture conditions and quality, the trained forensic image examiners more correctly and completely identified the test group of questioned vehicles make, model, and year. 相似文献
3.
Yoshinori Nishiwaki Ph.D. Sadao Honda M.S. Takuma Yamato M.S. Ryosuke Kondo M.S. Atsunori Kaneda M.S. Shinjiro Hayakawa Ph.D. 《Journal of forensic sciences》2020,65(5):1474-1479
In this study, the nondestructive differentiation of individual white polyester clothing fibers was accomplished via synchrotron radiation microbeam X-ray fluorescence (SR-μ-XRF) analysis. SR-μ-XRF with vertical focusing is a useful nondestructive method for the analysis of a single polyester clothing fiber. Kirkpatrick–Baez (KB) mirror was used to vertically focus 20 keV X-rays for the analysis of 22 individual white polyester fibers taken from clothing commonly sold in Japan. SR-μ-XRF with a vertical focused 2 μm (V) × 300 μm (H) beam was approximately 12.8 times more sensitive than SR-XRF with an unfocused 300 μm (V) × 300 μm (H) beam for the detection of elements in single fibers. The minimum detection limits (MDLs) of the SR-μ-XRF method were 8.15 ppm for Cl and 0.06 ppm for Br. In addition to Ti in TiO2 delustering agents, Zr and Nb impurities in the delustering agents were detected in individual fibers. Sb from a polymerization catalyst and Co from a transesterification catalyst were also detected in individual fibers. Comparing the Ti Kβ/Sb Lα,β and Zr Kα/Nb Kα X-ray intensity ratios was a useful way to distinguish individual clothing fibers, and 98% of the fibers were differentiated when additional trace elements were used as discrimination indicators. 相似文献
4.
ABSTRACT Brand hate is defined as a severe dislike for a product or service by the consumer. Although brand hate has been recognized as a critical element, in the political market, there is a lack of understanding of the impact of brand hate on voters. This study is an attempt to examine the antecedents and consequences of brand hate in the political market. The study reveals that unmet expectations, symbolic incongruity, and ideological incompatibility of electorates have a significant positive impact on brand hate intensity. The result shows that political product involvement significantly mediates the relationship between unmet expectations, symbolic incongruity, and ideological incompatibility and brand hate intensity. The study further reveals that as an outcome of political brand hate, electorates put emphasis on either brand avoidance and/or brand extremism. The outcome of this study may help political parties gain knowledge about the impact of political brand hate. 相似文献
5.
Aniseh Bassiri Tabrizi 《European Security》2020,29(3):320-336
ABSTRACT The negotiations with Iran about its nuclear programme have seen the most protracted involvement of the High Representatives of the European Union in a high-profile policy case. This article traces the evolution of the High Representatives’ participation in the negotiations, from the first contacts with the E3 (Germany, France and the United Kingdom) in 2003 to the adoption of the Joint Comprehensive Plan of Action in 2015. It focuses on the institutional role the High Representatives played in relation with the directoires leading the talks with Iran – first the E3 and, since 2006, E3/EU. In this context, it examines the personal and organisational factors that affected the influence each of the three High Representatives (Javier Solana, Catherine Ashton and Federica Mogherini) had in regard to the directoires. The analysis distinguishes specifically between the phases before and after the 2009 Lisbon Treaty. The article shows how similar personal qualities of the three High Representatives in terms of problem-solving and trust-building gave them political capital that enabled them to adopt a fairly constant role as bridge-builders within the directoires and between the directoires and other actors. The reforms of the Lisbon Treaty had only a minor impact. 相似文献
6.
Virginie Redouté Minzière M.Sc. Denis Werner M.Sc. Daniela Schneider M.Sc. Manuela Manganelli M.S. Balthasar Jung Ph.D. Céline Weyermann Ph.D. Anne-Laure Gassner Ph.D. 《Journal of forensic sciences》2020,65(4):1102-1113
Gunshot residue (GSR) analysis and their interpretation provide crucial information on a criminal investigation involving the use of firearms. To date, several approaches have been proposed for the implementation of a combined sampling and analysis of inorganic (IGSR) and organic GSR (OGSR). However, it is not clear at this stage if concurrent analyses of both types of residue might be detrimental to the analysis of IGSR currently applied in forensic laboratories. Thus, this work aims to compare and evaluate three different protocols for the combined collection and analysis of IGSR and OGSR. These methods, respectively, involve the use of a modified stub (with two halves, one for the detection of IGSR and the other for the analysis of OGSR); the sequential recovery of GSR with two stubs mounted with different adhesives (double-sided carbon tape and Tesa® TACK) and the sequential analysis of IGSR and OGSR from a single carbon stub following carbon deposition. The detection of IGSR was carried out using SEM-EDX, while OGSR analysis was performed using ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS). Obtained results for experiments performed using Geco Sinoxid® ammunition indicated that sequential analysis was the most suitable protocol for the combined collection and analysis of both IGSR and OGSR. A higher number of inorganic (characteristic and consistent) particles and higher concentrations of ethylcentralite, N-nitrosodiphenylamine, diphenylamine, and nitroglycerin were recovered with this method. 相似文献
7.
Matthew C. Benwell Alejandro F. Gasel Andres Núñez 《Bulletin of Latin American research》2020,39(4):424-438
This paper draws on recent research examining feminist and everyday geopolitics to focus on the relatively neglected domestic sphere as a space where geopolitical events like the Falklands/Malvinas war are learnt, (re)produced, remembered and contested by young people. It presents qualitative data drawn from interviews with young people from Argentina (Río Gallegos) and the Falkland Islands (Stanley), locations with intimate connections to the 1982 war. It argues that research in domestic environments that engages the familial relations, objects and practices that embody geopolitical pasts can help make sense of how young people (are able to) express geopolitical agency. 相似文献
8.
The U.S. electric power sector has experienced a substantial shift of the generation mix since the turn of the century, moving from heavy reliance on coal‐powered generation to one drawing more from natural gas and, more recently, renewables. This transition has been forged by a mix of macroeconomic factors (recession and recovery); technological breakthroughs (horizontal drilling coupled with hydraulic fracturing; improvements in natural gas plant efficiency); clean energy policies at federal, state, and local levels of government; and private sector demands for carbon‐free energy sources. These factors have combined to reduce carbon emissions from electric power generation substantially this century. In this article we examine the extent of this transition, its causes, as well as the distinct American institutional factors steering it, including energy and environmental federalism, electoral politics, and the political economy of clean energy policy enactment and resistance. 相似文献
9.
There have been significant developments over the past two decades that have expanded our understanding of the dynamics of parent–child contact problems post‐separation, which have resulted in some changes in judicial processes to respond to these cases. One significant advancement is a more sophisticated differentiation of the nature and severity of contact problems, which better assists legal and mental health professionals to provide more suitable legal and clinical interventions. However, the issue of innovative court processes has received limited attention. The authors describe a subgroup of families within the “severe” category, for whom an expanded intervention model, referred to as a Blended Sequential Intervention is proposed. This approach involves a reversal of care with court mandated therapeutic support for the rejected parent and child, but also involves the favored parent in the therapeutic plan from the outset, and is intended to avoid a permanent “parentectomy” of the child from either parent. The authors discuss how the courts should respond to these cases, and posit that until all therapeutic treatments are exhausted, interim orders should be preferred to final determinations, and judges should maintain oversight. The authors discuss the critical role of judicial leadership in working with lawyers and mental health professionals to manage and address the issues in these high conflict cases. 相似文献
10.
Access to reproductive health services and products in remote and rural communities is a critical area of concern for developing countries. This article considers a pilot intervention in three districts of Pakistan where “Business-in-a-Box” as a model of place-based social innovation is used to improve the socio-economic conditions of women in remote rural settings through socially responsible micro-franchising. It finds that such programmes help build a sense of community, ownership and grassroots capabilities and skills. The article also discusses the impacts of such actions on the individual and community life, and the need to upscale and sustain these initiatives. 相似文献