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241.
The reporting of a likelihood ratio (LR) calculated from probabilistic genotyping software has become more popular since 2015 and has allowed for the use of more complex mixtures at court. The meaning of “inconclusive” LRs and how to communicate the significance of low LRs at court is now important. We present a method here using the distribution of LRs obtained from nondonors. The nondonor distribution is useful for examining calibration and discrimination for profiles that have produced LRs less than about 104. In this paper, a range of mixed DNA profiles of varying quantity were constructed and the LR distribution considering the minor contributor for a number of nondonors was compared to the expectation given a calibrated system. It is demonstrated that conditioning genotypes should be used where reasonable given the background information to decrease the rate of nondonor LRs above 1. In all 17 cases examined, the LR for the minor donor was higher than the nondonor LRs, and in 12 of the 17 cases, the 99.9 percentile of the nondonor distribution was lower when appropriate conditioning information was used. The output of the tool is a graph that can show the position of the LR for the person of interest set against the nondonor LR distribution. This may assist communication between scientists and the court.  相似文献   
242.
This study describes the performance of handheld Raman devices for detecting one hundred opioids and related substances including fentanyl and several analogs. Using a single “parent” device, signatures (spectra) with excellent signal-to-noise ratios were generated using <5 mg of most compounds. The signatures were added to a method (library), which was electronically transferred to three “daughter” devices. The devices were able to discriminate different salt forms and isomers. On average, the daughter devices yielded a true-positive rate of 97.3% for generating an alarm for opioids and were 93.3% effective for correctly identifying the opioid. The devices yielded true-negative, false-positive and false-negative rates of 100%, 0%, and 2.7%, respectively, where false negatives were due to weak signal and fluorescence. These data demonstrate that the parent-daughter electronic transfer method was successful and effective, which permits the ability to develop methods in the laboratory that can be seamlessly pushed out to field devices.  相似文献   
243.
3D printers are becoming increasingly efficient and economical, and thus more widespread and easily accessible to consumers and businesses. They have been used to print nefarious objects such as guns and suppressors. Previous research has documented the release of dust particles during the printing process; however, little has been written about the morphology and chemical features that define the dust emitted by these printers. This study was undertaken to recover, analyze, and identify the dust produced during the printing process in the context of forensic trace evidence analysis. Samples were collected from a variety of 3D fused deposition modeler printers, representing both consumer and commercial grade models. This work focused on printers that use thermoplastic filaments composed of acrylonitrile butadiene styrene (ABS) or polylactic acid (PLA), two of the most commonly used filament polymers. Swabs were used to collect dust within the printer chamber and then processed to isolate the dust particles. Particles produced from ABS filaments are most easily recognized via light microscopy through a combination of color, morphology, and fluorescence. The composition of these particles can be confirmed through analysis by either FTIR or Raman microspectroscopy. These methods can also be used to identify ABS fillers and pigments within the printer dust particles. In contrast, dust from PLA printers consistently contained finer, submicron-sized particles that could be observed by field emission scanning electron microscopy. Because the size of the particles precludes their identification using vibrational spectroscopy methods, pyrolysis-GC-MS was used to confirm the presence of PLA.  相似文献   
244.
《Science & justice》2020,60(2):99-107
The purpose of this review paper is to highlight various geomatic techniques that crime scene reconstructionists or forensic practitioners can use to document different kinds of scenes, highlighting the advantages, disadvantages, and when best to use each technology. This paper explores geomatic techniques such as a total station, photogrammetry, laser scanners and structured light scanners and how they can be used to reconstruct crime scenes. The goal of this paper is not to discredit manual methods, as they are long standing and reliable, but instead to shed light on alternative methods that may produce equally or more accurate results with a more visually appealing final product. It is important for law enforcement and forensic professionals to understand the advantages and disadvantages of each technique, knowing when certain techniques should be used (and when they should not), and being able to revert to traditional methods if required.  相似文献   
245.
《Science & justice》2020,60(2):120-127
Proficiency testing has the potential to serve several important purposes for crime laboratories and forensic science disciplines. Scholars and other stakeholders, however, have criticized standard proficiency testing procedures since their implementation in laboratories across the United States. Specifically, many experts label current proficiency tests as non-representative of actual casework, at least in part because they are not sufficiently challenging (e.g., [1], [2], [3], [4]. In the current study, we surveyed latent print examiners (n = 322) after they completed a Collaborative Testing Services proficiency test about their perceptions of test items. We also evaluated respondents’ test performance and used a quality metric algorithm (LQMetrics) to obtain objective indicators of print quality on the test. Results were generally consistent with experts’ concerns about proficiency testing. The low observed error rate, examiner perceptions of relative ease, and high objective print quality metrics together suggest that latent print proficiency testing is not especially challenging. Further, examiners indicated that the test items that most closely resembled real-world casework were also the most difficult and contained prints of the lowest quality. Study findings suggest that including prints of lower quality may increase both the difficulty and representativeness of proficiency testing in latent print examination.  相似文献   
246.
This thesis analyzed the cross‐section data of 630 non‐financial listed enterprises and adopts a logit model to estimate the relationships between political relations and corporate environmental behavior. The paper also adopts an ordered logit method to estimate the marginal impact of political connections to enterprises’ disclosure of information on environment and sustainable development. Through analysis, this thesis found that political connections lower the probability for enterprises to disclose information on environment and sustainable development. With the Level III scoring method, this article classified the performances of disclosing corporate environmental information into three levels. It is found that corporate political connections increase the probability for enterprises not to disclose any environmental information and lower the probability for enterprises to refer to GRI Sustainability Reporting Guidelines.  相似文献   
247.
Our article explores the contribution of local initiatives to the creation of path dependencies for energy transition in Germany and Japan in the face of resistance from entrenched incumbents at the national level. We use a process‐tracing methodology based partly on interviews with local participants. In particular, we explore the role of local initiatives in securing “socio‐political space” for the expansion of renewable energy (RE) and in embedding themselves in “ecosystems” of public and private institutions. German energy activists were more successful than their Japanese counterparts in expanding this space and creating positive feedback in part because they were able to build horizontal networks that anchored the energy transition firmly in local communities. Although problems with grid technology have led to retrenchment in both cases, Japanese activists' reliance on vertical networks has limited their ability to weather a backlash from national government and utility actors. Our study demonstrates the interaction of political, economic/technological, and legitimation paths to energy transition and highlights the importance of the latter two.  相似文献   
248.
Sailer 《Juristische Bl?tter》2009,131(7):455-457
Es finden sich keine gesetzlichen Grundlagen, aus denen sich ein allgemeiner Grundsatz ableiten lie?e, es sei im gesch?ftlichen Verkehr generell von jedem Empf?nger zu verlangen, stets auf beh?rdliche Zustellungen gefasst zu sein und für eine Nachsendung oder Vertretung Vorsorge zu treffen, andernfalls die Wirkungen einer wirksamen Zustellung eintreten. Die Pflicht, die für Zustellungen ma?gebliche Gesch?ftsanschrift zum Firmenbuch anzumelden, ist nur mit Schadenersatzansprüchen gegen den Gesch?ftsführer sanktioniert.  相似文献   
249.
国际关系理论中的不同流派,由于看问题的视角不同,面对同一事物,其所看到的景象也不一样.对同一个以"10 3"为核心的东亚区域合作,建构主义学者看到的是其乐融融的规则建构景象,而现实主义学者看到的则是暗中较劲的权力之争.虽然有如此的不同,但二者对国家利益的强调,还是为我们调和二者的看法提供了线索.  相似文献   
250.
Gertrudis Gómez de Avellaneda’s Sab (1841) has come to be regarded as an iconic work in the canon of nineteenth‐century Cuban fiction, celebrated as much for its literary pedigree as for its radical combination of anti‐slavery and feminist ideas. Yet it has been the subject of very divergent critical appraisals. This essay sets out to breathe new life into Avellaneda’s novel by interpreting it through a postcolonial optic. Drawing on ideas from the scholarship of Edward Said and Frantz Fanon, as well as the ideas of literary theorist Mikhail Bakhtin, these pages explore the implications of its nationalist, racial, sexual and feminist politics for Sab’s anti‐slavery meaning. This postcolonial reading provides a possible solution for the conflicts between its various interpretations.  相似文献   
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