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31.
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.
  相似文献   
32.
This article characterizes the ways in which the actors in charge of designing and implementing public policies intervene to promote the emergence of alternatives to problematic technologies. It is based on a case study conducted in Argentina that focuses on initiatives to promote the development of biological agricultural inputs in the context of increasingly controversial chemical inputs. The study spotlights the political, institutional, and semantic efforts made by policy makers and public administrations to ensure these new inputs find their way into organizations and onto their agendas. Their work consists in attenuating the boundaries between chemical and biological inputs, and reducing opposition by creating categories and organizations that downplay potential dissension and highlight the possible coexistence of technological paradigms. Contrary to what the injunctions of technological substitution suggest, we show that putting alternative technologies on the public agenda depends largely on their inclusion in institutional and regulatory infrastructures originally designed for technologies that are likely to decline. More broadly, it relies on the construction of continuity between the two types of technologies.  相似文献   
33.
Understanding what stimulates agribusiness firms to lobby the government and what makes the government responsive to lobbying are the two issues that have been discussed extensively in the debates concerning determinants of biotechnology policy. This paper examines the factors influencing agribusiness firms' lobbying and government response using econometric modeling on a new data set of 160 leading agribusiness firms in the food, feed, chemical, and seed industries in China. The results show that approximately 10% of agribusiness firms lobbied the government about biotechnology policy and regulations and over half of those that lobbied received a verbal or written acknowledgment from government agencies. Seed and feed companies are more likely to engage in lobbying than chemical companies. Owning GM patents not only has a positive impact on firms' lobbying activities, but firms with these patents are more likely to receive a government response to their lobbying efforts. The experience of selling GM products does not significantly influence lobbying activities or response from the government.  相似文献   
34.
As the emergence of nongovernmental conservation efforts generates conflict among various stakeholders, the causal story that each party articulates regarding conservation and the causes of land degradation reflects their unique interests. This study uses existing literature to evaluate causal stories surrounding a contemporary conservation effort: Montana's American Prairie Reserve. Through qualitative review of web‐based documents and newspaper articles, it generates a preliminary account of key stakeholders' causal stories. The case study suggests that parties who might be disadvantaged by ascribing responsibility for environmental harms in an adversarial fashion may instead elect to articulate causal stories that are more neutral than existing approaches might forecast. The study concludes by suggesting that further development of causal story literature may enable it to better address contemporary conservation efforts.  相似文献   
35.
Establishing error rates is crucial for knowing how well one is performing, determining whether improvement is needed, measuring whether interventions are effective, as well as for providing transparency. However, the flurry of activities in establishing error rates for the forensic sciences has largely overlooked some fundamental issues that make error rates a problematic construct and limit the ability to obtain a meaningful error rate. These include knowing the ground truth, establishing appropriate databases, determining what counts as an error, characterizing what is an acceptable error rate, ecological validity, and transparency within the adversarial legal system. Without addressing these practical and theoretical challenges, the very notion of a meaningful error rate is limited.  相似文献   
36.
目的 研究大鼠骨骼肌挫伤后M1/M2型巨噬细胞浸润的动态变化规律结合组织学改变建立损伤时间推断方法.方法 建立大鼠骨骼肌挫伤模型,挫伤后6h、12h、24h、36h、48h、60h、72h、96h、144h、216h、336h为实验组,对照组不进行任何处理.采用HE染色法和免疫荧光多重染色方法观察骨骼肌挫伤后修复规律,...  相似文献   
37.
The global proliferation of precision-strike systems may be challenging the foundations of Western military-technological supremacy. Relatedly, the development of so-called Anti-Access and Area Denial (A2/AD) capabilities across the globe threatens to complicate Western freedom of military movement and access, and could give way to a more contested military-strategic environment. The twin challenges of precision-strike proliferation and A2/AD strongly impact NATO’s agenda, which revolves around strengthening deterrence and defence in Eastern Europe, and addressing the different threats emanating from the so-called Southern European neighbourhood. In order to address or mitigate such challenges, the Alliance needs to produce operational concepts and capabilities able to deliver deterrence and expeditionary warfare in a maturing precision-strike environment, one characterised by the emergence of A2/AD capabilities.  相似文献   
38.
应用RT-PCR和nPCR扩增由4株甘肃省近期(1997-1998)猪瘟流行野毒株的E2基因,将其克隆到pGEMTEasy载体上,经转化、筛选、鉴定后,测出核苷核序列.4株流行毒株的E2基因核苷酸序列同源性为89.2%-99.7%,相应的氨基酸序列同源性为93.8%-99.0%.这4株流行毒株;与C-株(疫苗种毒)E2基因的核苷酸序列同源性为82.2%-84.3%,相应的氨基酸序列同源性为87.9%-90.2%,表明近期猪瘟流行毒株与C-株的gp55蛋白之间存在一定的差异.  相似文献   
39.
Chris Ealham 《Labor History》2017,58(3):245-270
Revisionist historians and their Neo-Revisionist/conservative fellow travellers identify the Spanish left as the main cause of the civil war (1936–1939) that culminated in the establishment of the Franco dictatorship. Such claims are possible because these historians distort both the history of the left and the nature of social protest and mass mobilisation during these years. In part, the reliance of Neo-Revisionist/conservative historians on the methods of traditional political history – combined with their stubborn aversion to social history – makes it impossible for them to understand the left. This article argues that only through social history is it possible to comprehend the complex and shifting nature of protest dynamics in the 1930s. Indeed, many of the conflicts that played out in the political arena during these years were conditioned by structural economic problems and social tensions that resulted in diverse forms of radical contestation among the grassroots of leftist movements. Social, and indeed cultural history, are, therefore, central to any analysis of the myriad forms of these protest energies that flowed from the bottom up to shape the orientation of the leftist organisations.  相似文献   
40.
《Labor History》2012,53(4):423-458
Well known is that the National Labor Relations Act (NLRA, 1935) in the United States places a largely per se ban on nonunion employee representation (ER) groups which deal with employers over a term or condition of employment. Much less well known is that America’s other labor law, the Railway Labor Act (RLA, 1926), takes a different approach and permits employers to operate such councils and committees as long as they do not perform a collective bargaining function or interfere with workers’ free choice of a bargaining agent. Thus, under the RLA Delta Air Lines is able to operate what is today the closest living approximation to a 1920s-style ER plan while hundreds of other companies (e.g. Polaroid) under the jurisdiction of the NLRA have been forced over the years to disband similar groups on grounds they are a proscribed company union. No study to date has explored the history behind the RLA and NLRA’s divergent treatment of nonunion ER groups so this article takes a first look. The main part of the story covers the 1920–1935 period and examines the events, people, and experiences associated with company unions and ER in, respectively, the rail and manufacturing industries and why the legislative outcome in the former was a permissive stance on nonunion committees but prohibitive in the latter. The last part of the paper fast-forwards the RLA-NLRA story from the 1930s to contemporary law and practice in order to demonstrate how “history matters” when it comes to what employers can and cannot do with nonunion representation groups, such as works councils, participation and involvement committees, and dispute resolution forums.  相似文献   
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