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221.
mtDNA COI和ND5基因用于鉴别常见嗜尸性蝇类 总被引:1,自引:1,他引:0
目的对蝇类mtDNA 523bp COI和347bp ND5基因片段进行序列分析,评价其在以嗜尸性蝇类种属鉴定中应用的可行性。方法从广州(广东省)、湛江(广东省)、韶关(广东省)、沈丘(河南省)及蜂蛹寨(四川省)采集7种嗜尸性蝇类标本,进行形态学种属鉴定,取其腹部肌肉提取DNA,利用基因特异性引物对线粒体COI、ND5基因进行PCR扩增,产物经纯化后进行测序,MEGA 3.0软件对DNA序列进行碱基组成、进化分歧率和系统发育分析。结果进化分歧率ND5基因种内小于1.83%,种间大于2.62%;种间与种内进化分歧率范围间没有交叉;COI基因种间在0.48%~14.8%之间,种内在0.24%~8.3%之间,种内进化分歧范围与种间进化分歧范围存在交叉。结论 ND5基因片段可在种水平有效鉴别常见嗜尸性蝇类,也可鉴别近缘种。而单独运用COI基因不能有效进行种属鉴定。 相似文献
222.
Yesim Dogan Alakoc Omer Gokcumen Aysim Tug Timur Gultekin Erksin Gulec Theodore G. Schurr 《Forensic Science International: Genetics Supplement Series》2010,4(5):e135-e137
Due to the longstanding human presence in the region and the influence of social traditions, the genetic make-up of populations currently inhabiting Turkey (Anatolia) is quite complex. To characterize the patterns of genetic diversity in rural Central Anatolian villages, we analyzed samples collected at four local settlements for variation at 17 Y-chromosome STR and 15 autosomal STR loci. The resulting data reveal considerable diversity within these settlements, as well as some structure in the paternal genetic variation, with a limited number of haplotypes being shared between the communities. These findings have important implications for forensic studies of Turkish populations. 相似文献
223.
Abstract: DNA amplification is a fundamental yet costly process used in DNA analysis. This study evaluated half‐reaction amplification (12.5, 12, and 13 uL) using the Promega Powerplex® 16 Kit with the hope of reducing sample analysis costs by half. A sensitivity study was completed, along with the testing of various blood stain samples including those with low (<0.40 ng) and high DNA concentrations (>3.0 ng), peak height imbalances, and allelic drop‐out. Also, 467 samples submitted to the MUFSC laboratory for testing were analyzed. Results indicate that half‐reaction amplification produced higher quality profiles than full‐reactions. Average peak heights increased by 85%, peak height imbalances improved, and drop‐out was eliminated in 75.8% of samples. Only eight of 467 case samples required re‐amplification, a success rate of 94% was observed, and the repeat rate decreased significantly. Finally, a DNA input of 0.25–1.0 ng is ideal for half‐reaction amplification. 相似文献
224.
采用活病毒免疫,常规杂交瘤融合的方法,获得了4株针对H5N1亚型禽流感病毒(AIV)A/duck/Shandong/093/2004(A/D/SD/04)株血凝素(HA)的单克隆抗体A8E8、D2F8、A8C8和C3G4。其中A8E8可以与11株不同来源的H5N1AIV发生交叉免疫抑制性反应(HI),具有广谱性。采用间接免疫荧光试验(IFA),用A8E8单克隆抗体测定A/D/SD/04株对COS1和MDCK2种细胞的半数感染量(TCID50),结果显示,A/D/SD/04株在COS1上的TCID50为10-5.33/0.1mL,在MDCK上的为10-7.33/0.1mL。将编码A/D/SD/04株的HA基因质粒与PR8质粒共转染COS1细胞后,用A8E8进行IFA,能观察到特异性绿色荧光,这与鸡胚接种结果相符。表明,用此单克隆抗体能准确地检测到H5重组病毒。 相似文献
225.
226.
The impact of environmental regulation on the competitiveness of firms and industries remains a hot topic. Since the formulation of the Porter hypothesis, scholars from different research areas have tried to confirm or deny it. However, despite a vast literature engaging this debate, it remains unclear whether and under what conditions the hypothesis could be considered valid. We believe that this is due to the need to consider some additional factors. The aim of this review is to propose additional and significant themes, namely value appropriation and pollution intensity, to be considered when examining the impact of environmental regulation on the innovation and profitability of firms. Results show that the validity of the Porter hypothesis cannot be proved in any condition, but at the same time, there are additional factors that have a relevant influence on that construct, which can lead to a validation or rejection of the hypothesis. 相似文献
227.
China launched its national emissions trading scheme (ETS) in late 2017. This article examines the key drivers behind China’s 2011 decision to opt for ETS as a GHG mitigating policy tool and what lay behind the choice of the system’s design features. Given the existence of the frontrunner EU ETS and that market mechanisms have spread across the world in recent years, we analyze the role played by policy diffusion in the decision to launch an ETS and in the subsequent design process, seen in relation to domestic drivers. The article investigates policy developments culminating in the 2011 carbon market announcement, and the reasons these design elements were chosen for the pilot schemes and the national market in the period 2011–2017. The article contributes to our understanding of policy diffusion at different stages of policy development in China, by revealing which diffusion mechanism is more prevalent at different stages. We find first that overall domestic conditions and drivers had the most consistent impact on policy decisions to establish a carbon market and on the selected sectors. However, a second key finding is that the role of policy diffusion varied over time, with such diffusion, in the form of ideational impact, playing the most important role early on, providing a powerful inducement for China to go for a carbon market. Third, sophisticated learning from international projects took place in the pilots, allowing China to adapt policies and design features to match local conditions. 相似文献
228.
Sarah Kilpelinen Pami Aalto Pasi Toivanen Pinja Lehtonen Hannele Holttinen 《政策研究评论》2019,36(4):448-472
The Nordic countries pursue ambitious energy transition goals through national energy policies and in the framework of Nordic cooperation. We propose that the transition is realistic only if it involves the public, private, and nongovernmental organization sectors as regulators, innovators, and advocates of relevant policies and solutions representing the multitude of interests involved. We examine these interests through Q methodological experiments, where 43 expert stakeholders’ rank‐order statements concerning their preferred policy measures vis‐à‐vis the electric energy system. Factor analysis of these subjectively held views produces three distinct views. The first two enjoy strong inter‐Nordic support. The first view prioritizes market and grid development, and the second view prioritizes electric transport, and solar and wind power. The third, “Finnish” view seeks to enhance security of supply, also via microgrids, and prioritizes biofuels over electric transport. Examining the common ground among the three views, we find that enhanced cooperation requires reinforced stakeholder interaction and policy coordination. 相似文献
229.
Increasingly severe wildfires have focused attention on forested watershed vulnerabilities, causing significant changes to policies and governance. We utilized the Multiple Streams Approach (MSA) to understand institutional innovations of federal agency–large water provider partnerships in Colorado to protect watersheds through joint planning and funding. Ambiguous problem definition and focusing events were significant aspects of these partnerships. We interviewed individuals in the partnerships, with MSA ideas of how solutions to policy problems develop, and the role of policy entrepreneurs. We found that wildfires served as focusing events, creating space and time for learning, collaboration and new problem framing, increased political attention, and institutional innovation. In this study, windows of opportunity stayed open longer, policy entrepreneurs and agencies played larger roles in communication and coupling streams and the context of fast‐moving, unpredictable ecological crises changed responses to issues. Our findings also have implications for broader policy studies and environmental governance scholarship. 相似文献
230.
Latent Fingerprint Development on Thermal Paper Using Traditional Ninhydrin and 1,2‐indanedione
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Chun‐Chieh Chen M.S. Yung‐Chien Yu M.S. Henry C. Lee Ph.D. Yun‐Seng Giang Ph.D. Sheng‐Meng Wang Ph.D. 《Journal of forensic sciences》2016,61(1):219-225
Thermal paper poses a significant challenge to latent print development as it tends to change color when traditional fingerprint development formulations are applied to it. In this study, the optimal components of ninhydrin, 1,2‐indanedione, 1,8‐diazafluoren‐9‐one (DFO), and 5‐methylthioninhydrin (5‐MTN) for yielding clear fingerprints on thermal paper were determined by systematically adjusting the relative amounts of the reagents, polar solvents, and the nonpolar diluent petroleum ether, followed by validation on text‐printed thermal paper. Specifically, 3.0% ethyl acetate as the polar solvent in petroleum ether was found to be the optimal combination; the optimal dilution ratios of ninhydrin, DFO, and 5‐MTN original solutions with petroleum ether were 1 to 2, 11, and 7, respectively. The optimal concentration of 1,2‐indanedione in petroleum ether was 0.125 g/L, with a string of 0.5% ethyl acetate in petroleum ether. 相似文献