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31.
Noah Zerbe 《政策研究评论》2007,24(5):407-423
Debates over the future of new technologies frequently implicate governmental policies and regulation, the purpose of which has traditionally been to mitigate the dangers of new technologies through promotion of conditions of safe use. It is increasingly recognized, however, that regulation is predicated on a particular conception of the nature of risk which may or may not correspond to the views and beliefs held by society. Here I explore three broadly related questions in the context of the debates around agricultural biotechnology. First, what are the implications of varying conceptions of risk for regulatory policy in the United States and in the European Union? Second, what are the implications of differing conceptions of risk and resulting regulatory policy for agricultural trade relations between the two giants of international trade? And finally, what lessons might we draw from contemporary disputes over agricultural biotechnology? 相似文献
32.
Zhijian Wen PhD James M. Curran PhD SallyAnn Harbison PhD Gerhard E. Wevers 《Journal of forensic sciences》2023,68(6):1946-1957
Crimes, such as robbery and murder, often involve firearms. In order to assist with the investigation into the crime, firearm examiners are asked to determine whether cartridge cases found at a crime scene had been fired from a suspect's firearm. This examination is based on a comparison of the marks left on the surfaces of cartridge cases. Firing pin impressions can be one of the most commonly used of these marks. In this study, a total of nine Ruger model 10/22 semiautomatic rifles were used. Fifty cartridges were fired from each rifle. The cartridge cases were collected, and each firing pin impression was then cast and photographed using a comparison microscope. In this paper, we will describe how one may use a computer vision algorithm, the Histogram of Orientated Gradient (HOG), and a machine learning method, Support Vector Machines (SVMs), to classify images of firing pin impressions. Our method achieved a reasonably high accuracy at 93%. This can be used to associate a firearm with a cartridge case recovered from a scene. We also compared our method with other feature extraction algorithms. The comparison results showed that the HOG-SVM method had the highest performance in this classification task. 相似文献
33.
In 2011, Canadian Members of Parliament refused to transfer a regulatory initiative taken from Argentina that would have required an analysis of potential harm to export markets before authorizing the sale of any new genetically modified seed. This was the purpose of Bill C‐474, which was defeated in the House of Commons. After exploring Argentina's regulatory framework as a source of transfer, this paper combines a multilevel analysis with a typology of policy transfer mechanisms in order to address the complexities underlying this unsuccessful attempt. We explore how the mechanisms of competition and coercion might have impeded the transfer of such an initiative at the international and the macro‐state levels. Moreover, while a policy transfer network in support of the bill called on previous experiences with genetically modified seeds, their efforts appear to have been outweighed by another network using arguments based on the mechanisms of competition, coercion, and mimicry. 相似文献
34.
郭彩玲 《胜利油田党校学报》2013,(6):83-86
在规范转基因产品的众多法律制度当中,转基因产品是否进行标识,既体现着一国对转基因产品的态度,也影响着一国政治经济的发展。总结各国学者对转基因产品标识的研究,着眼于保障国家粮食供应和粮食安全,尽可能将转基因产品的风险最小化。设计适合我国国情的转基因产品标识制度,并用法律制度对其进行规制,成为我国目前面临的重要问题之一。 相似文献
35.
目的对不同方法提取甲醛固定组织中DNA的效果进行比较,寻找一种操作简便、经济实用、质量较高的DNA提取方法。方法取甲醛固定的心肌组织14份,分别以改良酚-氯仿法,改良Trizol法,试剂盒法提取DNA,进行紫外分光光度计测定OD260/OD280值后,经PCR扩增,琼脂糖凝胶电泳分析确定提取的DNA质量。结果改良酚-氯仿法,改良Trizol法,试剂盒法OD260/OD280比值分别为1.841 5±0.380 4、1.370 5±0.336 7、0.831 6±0.175 0。两两比较均有显著性差异(P<0.05)。3种不同方法提取DNA含量分别为0.943 8±0.530 1、0.707 5±0.423 6、0.342 8±0.182 5。PCR扩增后琼脂糖凝胶电泳显示以改良酚-氯仿法所提DNA的谱带清晰度好于其它两种方法。结论改良酚-氯仿法简便有效,所用试剂价格低廉,是一种经济实用的甲醛固定组织DNA提取方法。 相似文献
36.
Daniele Merli Ph.D. Alberto Amadasi M.D. Debora Mazzarelli B.A. Annalisa Cappella B.A. Elisa Castoldi B.A. Stefano Ripa B.A. Lucia Cucca B.A. Cristina Cattaneo Ph.D. Antonella Profumo Ph.D. 《Journal of forensic sciences》2019,64(2):558-564
This study concentrates on samples of bare pork skin, with and without bristles, and dried bovine ribs shot with a semi‐automatic pistol to find the best methodology and sampling surface in the search for inorganic gunshot residues (IGSR). Four quadrants of known surface areas were sampled at different distances from the bullet's hole with different swabs: tapes in graphite, Leukosilk® white tape, 3M® transparent tape, and a cotton swab to assess the technique able to collect the highest amounts of IGSR with the lowest contribution of the blank. The cotton swab wet in 10% HNO3 gave the best results. The highest amounts of IGSR, measured by ICP‐OES and MS, were detected on a surface of 3‐cm radius from the bullet's edge. The amount of metals collected decreased with the firing distance between 20 and 60 cm. The procedure was efficient for sampling different tissues like skin and bones. 相似文献
37.
改良醋酸铵盐析法提取福尔马林固定石蜡包埋组织DNA 总被引:1,自引:1,他引:1
目的采用改良醋酸铵盐析法提取福尔马林固定石蜡包埋组织DNA,并评价其应用价值。方法取死后24h内人体肾组织用10%中性福尔马林溶液固定7d,石蜡包埋。采用酚/氯仿法、Chelex-100法及改良醋酸铵盐析法提取DNA。经用紫外分光光度计法、AGE及PCR-PAGE检测比较不同方法提取DNA的质量。结果改良醋酸铵盐析法、酚/氯仿法、Chelex-100法OD260/OD280比值分别为1.962±0.195、2.110±0.470、1.018±0.124,两两比较均有显著性差异(P<0.05);3种方法提取DNA含量(μg)分别为0.515±0.447、0.328±0.345、5.346±1.994;AGE电泳图谱可印证上述结果;PCR-PAGE检测显示改良醋酸铵盐析法提取DNA的谱带清晰度好于其它两种方法。结论改良醋酸铵盐析法更适合微量福尔马林固定石蜡包埋组织样本DNA的提取。 相似文献
38.
科学技术的发展一直在对国家安全的内涵产生影响,技术能力的发展会增加威胁国家安全的手段和模式,科学技术的滥用也会危及社会安全。生物技术在近半个多世纪以来发展极为迅猛,其影响面极广,涉及微生物、动植物、生态环境、医学、农业、粮食、生化战争、生物恐怖主义、人的健康、人口安全等方面,其覆盖领域的广度和深度是其他任何技术都无法比拟的。生物欠防备是指在现实生物安全威胁面前准备不充分和应对不够有效的状况。中国既处于生物欠防备状态,也处于一定程度的生物欠防卫状态,这表现在中国的药物(含疫苗)、水、粮食、种子均处于不设防开放的状态。造成这种状态的根本原因是认识问题,生物技术本身具有前沿性、复杂性,其管理具有跨军民界限、跨学科界限、跨政府部门界限、跨政府任期界限、跨国界的特点,中国现有管理模式不适应这些特点。今后,应密切关注和防范生物技术研发与应用过程中特有的安全风险以及生物技术被有意识用于安全威胁的现实可能性和严重危害性。 相似文献
39.
对"黑社会组织"概念的词义分析与实证考究 总被引:1,自引:0,他引:1
郭子贤 《中国人民公安大学学报(社会科学版)》2005,21(6):77-83
黑社会组织是指由众多成员组成,有严密的组织性和组织亚文化,使用暴力、威胁手段,或以其为后盾,控制一定的社会区域或行业,向权力部门渗透并建立保护伞,以牟取经济利益为最终目的的半隐蔽的社会群体.黑社会组织具有成员众多性、暴力性、组织严密性、垄断性、获取经济利益目的性、半隐蔽性、形成自己的亚文化、建立保护伞等特性.凭借权力庇护和组织暴力,在一定社会区域或行业牟取经济利益是黑社会组织的本质特征. 相似文献
40.
目的 研究2005式9mm警用转轮手枪射击弹壳痕迹,为警用转轮手枪射击弹壳痕迹检验鉴定提供理论依据.方法 预实验中选取10把警用转轮手枪以单动、联动方式分别射击收取弹壳样本,观察识别射击弹壳上各个痕迹的位置、形态及相互关系;补充验证实验中选取其中5把警用转轮手枪以单动方式分别进行射击实验,完善、验证预实验中得出的结论.结果警用转轮手枪射击弹壳上的烟垢痕迹、弹底窝痕迹及击针头痕迹的分布位置、形态具有规律性,具备检验鉴定价值.结论 利用弹底窝痕迹、烟垢痕迹结合击针头痕迹,可以实现射击弹壳的准确定位;利用烟垢痕迹、弹底窝痕迹及击针头痕迹具有推定弹壳先后射击顺序的可能性;通过弹底窝痕迹、击针头痕迹的细节特征比对,可以实现射击枪支的同一认定. 相似文献