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1.
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   
2.
胡冬华 《理论建设》2021,(1):100-107
中国共产党人的“五四阐释”是指中国共产党人自五四运动以来,对五四运动的回忆、评价与反思。在新民主主义革命时期,中国共产党人从革命的领导力量、动力、阶段划分及任务等方面阐释五四运动,建构了“五四阐释”的革命话语;在社会主义建设和改革开放时期,中国共产党人从社会主义建设的伟大奋斗目标、各阶段历史任务及青年的奋斗方向等方面阐释五四运动,建构了“五四阐释”的建设话语。文章回溯了中国共产党人“五四阐释”的建构历程,对深化五四运动的研究,更好地继承和弘扬五四精神具有重要意义。  相似文献   
3.
The U.S. electric power sector has experienced a substantial shift of the generation mix since the turn of the century, moving from heavy reliance on coal‐powered generation to one drawing more from natural gas and, more recently, renewables. This transition has been forged by a mix of macroeconomic factors (recession and recovery); technological breakthroughs (horizontal drilling coupled with hydraulic fracturing; improvements in natural gas plant efficiency); clean energy policies at federal, state, and local levels of government; and private sector demands for carbon‐free energy sources. These factors have combined to reduce carbon emissions from electric power generation substantially this century. In this article we examine the extent of this transition, its causes, as well as the distinct American institutional factors steering it, including energy and environmental federalism, electoral politics, and the political economy of clean energy policy enactment and resistance.  相似文献   
4.
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   
5.
We present results of our study on the stability of 4-chloromethcathinone (4-CMC) in authentic postmortem peripheral blood and vitreous humor samples. The stability of 4-CMC was determined in postmortem blood samples (for a period of 90 days) and vitreous humor (30 days) at three different temperatures: −15°C, +4°C, and + 23°C. The analyses were carried out using ultra-high-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (UHPLC-QqQ-MS/MS). In both materials, the lowest 4-CMC stability was demonstrated at room temperature. The blood samples stored in a freezer (−15°C) showed stability for the entire study period (90 days), while in the case of the vitreous humor sample stored at the same temperature the concentration of the substance decreased by 53% after 30 days. The study carried out in authentic postmortem blood and vitreous humor samples confirms the previous reports of 4-CMC instability in biological material. Authors suggest that the biological material should be stored frozen until analyses are carried out as soon as possible after collection of the material.  相似文献   
6.
为了开发一种抗I群4型禽腺病毒(FAd V-4)的亚单位疫苗,选择I群禽腺病毒血清4型流行毒株衣壳蛋白Fiber-2作为保护性抗原蛋白。利用昆虫细胞-杆状病毒系统生产Fiber-2蛋白,通过Westernblot检测重组蛋白的表达情况,利用双向琼脂扩散法检测重组Fiber-2的免疫原性。为了增强亚单位疫苗的免疫保护效果,添加鸡源白细胞介素2(chIL-2)和鸡源γ-干扰素(ch IFN-γ)作为免疫佐剂,与重组Fiber-2单独或混合使用,制备多种形式的亚单位疫苗,并进行动物攻毒保护试验。重组蛋白的Western-blot鉴定结果显示,63 ku处出现Fiber-2蛋白目的条带;双向琼脂扩散试验结果显示,重组蛋白效价达到1∶128,表现出良好的反应原性。动物攻毒保护试验结果显示,单独使用Fiber-2免疫SPF鸡,在50 μg/只的剂量下,可为SPF鸡提供100%的保护效果,以chIL-2和chIFN-γ为免疫佐剂,与重组Fiber-2联合免疫SPF鸡,可显著增强Fiber-2在低剂量(10 μg/只)下的免疫保护效果,上述结果表明重组Fiber-2联合chIL-2和chIFN-γ细胞因子佐剂所制备的亚单位疫苗在抗I群4型禽腺病毒感染领域具有良好的应用前景。  相似文献   
7.
International research collaboration (IRC) is associated with both positive and negative effects on the performance of research in emerging economies. While some authors claim that North–South collaborations improve scientific quality and visibility for Southern countries, others claim that it may entail the reorientation of research to comply with Northern agendas. South–South collaborations are thought to increase the focus on local affairs, therefore leading to a relatively small number of scientific international publications appearing in “high quality” journals. Research on the impact of IRC beyond publications in international journals has been neglected despite the importance of other products in knowledge creation. This research uses a broad range of scientific outputs to empirically assess such assumptions and explore the outcomes of IRC in Colombia. Results from multivariate regressions and nonparametric analyses show that, contrary to common assumptions, Colombian research teams collaborating with partners from the global South report higher scientific production, while those collaborating with Northern countries seem to contribute to local knowledge the most.  相似文献   
8.
9.
《政策研究评论》2018,35(4):617-641
Research on regulation has traditionally focused on studying the delegation of regulatory competencies from political principals to an independent regulatory agency. In this article, we argue that this delegation is nuanced by different factors that affect whether a specific regulatory decision is formally delegated. We examine and explain formal delegation patterns at the level of individual regulatory decisions in twelve countries located in Europe, Latin America, and South Asia. The data were gathered by coding the twelve countries' telecommunications legislation. The data analysis was undertaken using a classification tree model—a nonparametric model. We found that the maturity of the market has the greatest effect on the formal delegation of regulatory decisions, but this effect is also influenced by the other theoretical factors considered, particularly the level of political constraints and the type of regulation.  相似文献   
10.
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   
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