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211.
中国成都汉族及泰国群体D7S2846基因座的遗传多态性   总被引:2,自引:0,他引:2  
研究STR基因座D7S2 846的遗传多态性 ,为法科学应用提供基础数据。应用PCR及PAG电泳技术 ,对376名中国成都汉族无关个体及 131名泰国无关个体进行了调查。两群体分别检出 8个和 7个等位基因 ,首次获得该基因座基因在两群体中的频率分布。两群体基因型频率分布均符合Hardy Weinberg平衡。家系调查证实了等位基因的传递遵循孟德尔遗传规律。该基因座在两群体中的个人识别能力 (Dp)分别为 0 85 70、 0 86 0 2 ,杂合度 (H )分别为0 6 915、 0 6 870 ,多态性信息含量 (PIC)分别为 0 6 445、 0 6 5 5 3 ,非父排除率 (PE )分别为 0 415 2、 0 40 85。D7S2 846基因座在法医学个人识别及亲子鉴定中具有较高的实用价值。  相似文献   
212.
Structured light scanning is a noninvasive, accurate, and cost-effective 3D imaging technique, but due to reflection issues is yet to be utilized for tool mark analysis on fresh bone. During imaging, reflection from shiny surfaces, such as greasy bone, disrupts image formation. This study tested the David SLS-1 scanner's ability to image saw marks and explored six strategies to reduce reflection by [1] dulling the surface or [2] altering the projected light. The surface was dulled by freezing, talcum powder, dulling spray, or compressed air. The projected light was altered with a diffuser or limited to single pattern-coded. Results demonstrated that the resolution was insufficient for capturing minute details of striae. All six tests failed to reduce reflection sufficiently to produce complete images, but projecting vertical pattern-coded light showed the most promise. Future research is required concentrating on enhancing resolution and exploring the role of pattern-coded light in reducing reflection.  相似文献   
213.
There has been a rapid development and utilization of three-dimensional (3D) printing technologies in engineering, health care, and dentistry. Like many technologies in overlapping disciplines, these techniques have proved to be useful and hence incorporated into the forensic sciences. Therefore, this paper describes how the potential of using 3D printing is being recognized within the various sub-disciplines of forensic science and suggests areas for future applications. For instance, the application can create a permanent record of an object or scene that can be used as demonstrative evidence, preserving the integrity of the actual object or scene. Likewise, 3D printing can help with the visualization of evidential spatial relationships within a scene and increase the understanding of complex terminology within a courtroom. However, while the application of 3D printing to forensic science is beneficial, currently there is limited research demonstrated in the literature and a lack of reporting skewing the visibility of the applications. Therefore, this article highlights the need to create good practice for 3D printing across the forensic science process, the need to develop accurate and admissible 3D printed models while exploring the techniques, accuracy and bias within the courtroom, and calls for the alignment of future research and agendas perhaps in the form of a specialist working group.  相似文献   
214.
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   
215.
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   
216.
Energy transitions are fiercely contested. The incumbents of the fossil‐ and nuclear‐based energy systems have much to lose from a transition to a sustainable and decentralized energy system. They therefore employ their material and political resources to reverse, halt, or slow down this transition. They also attempt to stop and reverse the decentralization of energy production. This article provides a framework that can be used to analyze the contestation that surrounds energy transitions. The analytical framework breaks apart the macro paths of energy transitions, and differentiates between three meso‐paths (political, economic‐technological, and legitimation), emphasizes the feedback processes between these paths, and acknowledges the crucial role that actors play in engendering these feedback processes. It uses Germany as a case study to illustrate the analytical model. It also provides hypotheses that will be tested in the subsequent contributions to this special issue.  相似文献   
217.
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   
218.
《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   
219.
《政策研究评论》2018,35(1):61-88
This article investigates whether different political institutions such as executives, legislatures, parties, party systems, judiciaries, decentralization, constitutionalism, and referendums across 24 Western democracies are venues for debate across five individual morality policies. Using data since 1945, the article compares three theories of morality policy—(1) Policy Type leading to different institutional venues; (2) Two Worlds of religious/secular party systems; and (3) U.S./European exceptionalism. In order, the most frequently debated issues are abortion, same sex marriage, euthanasia, stem cells/assisted reproductive technology (ART), and capital punishment. There is considerable variation in the institutions and country groups that debate them although fewer differences in the Two Worlds model. Abortion, euthanasia, and same sex marriage are the most convergent issues across institutions, party systems, and country groupings while capital punishment and stem cells/ART show the most diverse patterns of deliberation. The general Policy Type model of morality policy is upheld, but varies institutionally by specific issues. The Two Worlds model is of some importance, but only on three issues. There also are regional differences between the United States, Europe, and non‐European democracies.  相似文献   
220.
《政策研究评论》2018,35(1):120-152
Over the past three decades, various power sector reforms have overhauled the governance of electricity generation, transmission, and distribution in almost a hundred countries. Have these reforms produced benefits? Using instrumental variables, we improve upon earlier studies and demonstrate that power sector reforms enacted between 1982 and 2008 have both had large positive effects on the availability of generation capacity and reduced transmission and distribution losses. We also show that the positive effects on generation capacity are pronounced in developing countries and that hybrid reforms falling short of privatization and free competition are effective in improving generation capacity in particular. Overall, the results show that these reforms are an effective tool to remove an important constraint on economic growth.  相似文献   
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