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71.
ABSTRACT

Across the political spectrum, people favour renewable energy. For political liberals, this support has been attributed to concern for the environment; in contrast, the bases of conservatives’ support are less clear. Derived from interviews with a diverse sample of households in Washington State, USA, and a vignette experiment with a representative sample of American households, results show that Democrats (liberals) and Republicans (conservatives) have different moral intuitions, with Democrats emphasizing communion and both Democrats and Republicans valuing self-sufficiency. These findings explain how politically polarized environmental attitudes can exist alongside a shared support for renewable energy. The study therefore contributes to the literature on environmental concern and behaviour, and has implications for policies aimed at increasing adoption of renewable energy as well as pro-environmental behaviour more broadly.  相似文献   
72.
Bracy Knight  Kevin  Seddon  Emily S.  Toombs  Theodore P. 《Ambio》2020,49(6):1232-1240

Biodiversity mitigation is a cornerstone of applied conservation. Mitigation encompasses a suite of practices, ranging from planned avoidance of impacts to creation of new natural habitats. Accurate and appropriate metrics quantifying impacts to natural systems and the effectiveness of restoration are necessary to measure the success of different mitigation strategies. Because effective mitigation requires adequate metrics, we developed a Biodiversity Metrics Framework to assist practitioners and policy makers in assessing biodiversity mitigation metrics. Based on Noss’ Hierarchy of Biodiversity, the Scorecard highlights the mismatch between scientifically defined best practices and metrics required by policy. The Framework may serve a vital role in standardizing and validating mitigation projects into the future.

  相似文献   
73.
Market-based conservation mechanisms are designed to facilitate the mitigation of harm to and conservation of habitats and biodiversity. Their potential is partly hindered, however, by the quantification tools used to assess habitat quality and functionality. Of specific concern are the lack of transparency and standardization in tool development and gaps in tool availability. To address these issues, we collected information via internet and literature searchers and through conversations with tool developers and users on tools used in U.S. conservation mechanisms, such as payments for ecosystem services (PES) and ecolabel programs, conservation banking, and habitat exchanges. We summarized information about tools and explored trends among and within mechanisms based on criteria detailing geographic, ecological, and technical features of tools. We identified 69 tools that assessed at least 34 species and 39 habitat types. Where tools reported pricing, 98% were freely available. More tools were applied to states along the U.S. West Coast than elsewhere, and the level of tool transferability varied markedly among mechanisms. Tools most often incorporated conditions at numerous spatial scales, frequently addressed multiple risks to site viability, and required 1–83 data inputs. Most tools required a moderate or greater level of user skill. Average tool-complexity estimates were similar among all mechanisms except PES programs. Our results illustrate the diversity among tools in their ecological features, data needs, and geographic application, supporting concerns about a lack of standardization. However, consistency among tools in user skill requirements, incorporation of multiple spatial scales, and complexity highlight important commonalities that could serve as a starting point for establishing more standardized tool development and feature-incorporation processes. Greater standardization in tool design may expand market participation and facilitate a needed assessment of the effectiveness of market-based conservation.  相似文献   
74.
A prenatal diagnosis was performed in 51 pregnancies with a 1-in-4 risk of having a child with cystic fibrosis. The criteria for determining an affected fetus were based on the results of alkaline phosphatase (ALP) residual activity after inhibition by phenylalanine and by homoarginine, of total ALP activity, and of gamma-glutamyltranspeptidase (GGTP) activity in the amniotic fluid taken between 16 and 19 weeks of pregnancy. The chromosomal analysis of amniotic fluid cells showed trisomy 13 in one case which was excluded from the analysis of biochemical assays. The biochemical assays were in the normal ranges in the amniotic fluid of 35 pregnancies: 26 have reached term and a normal infant has been born, 9 are still in progress. A deficiency of the ALP phenylalanine-inhibitable form, depressed values of total ALP and GGTP were observed in the amniotic fluid of 15 pregnancies: one pregnancy went to term and the infant had CF, in 14 cases the pregnancy was terminated, and meconium ileus was observed in ten of these cases. It was observed that the changes towards abnormal values became more significant with advancing gestational age and that 18 weeks appeared to be the optimum time for diagnostic amniocentesis.  相似文献   
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We conducted five bioassays to study how queens control the execution of sexual larvae by workers in colonies of the red imported fire ant, Solenopsis invicta. In each assay, subset colonies were made from many large polygyne colonies, and the 20 sexual larvae they contained were monitored over time. Sexual larvae mostly survived in queenless colonies, but were mostly killed in colonies with a single dealated queen, regardless of whether or not the queen was fertilized. The larvae were also killed when fresh corpses of queens were added to queenless colonies. Whereas acetone extracts of queens did not produce a significant increase in killings, extracts in buffered saline induced workers to execute most sexual larvae, indicating successful extraction of an execution pheromone. We identified the probable storage location of the chemical as the poison sac, and found both fresh (1 day) and old (21 day) extracts of poison sacs to be equally effective in inducing executions. The pheromone is stable at room temperature, perhaps because venom alkaloids also present in the extracts keep the pheromone from degrading. It is apparently either proteinaceous or associated with a proteinaceous molecule, a novel finding, as no queen pheromone of a proteinaceous nature has been previously demonstrated in ants.  相似文献   
78.
Favella panamensis Kofoid and Campbell, 1929 is seasonally abundant in meso- to polyhaline waters of Chesapeake Bay and Indian River, Florida, USA, where it reaches densities of 103 cells l-1. During the summers of 1986–1992. F. panamensis populations of the two estuaries were commonly infected by the parasitic dinoflagellate Duboscquella aspida Cachon, 1964. The intracellular phase of the parasite reached maturity in 21 h (30 °C) and consumed 35% of the host's biomass. Infections were not typically lethal to F. panamensis, but sometimes forced the host from its lorica. Several D. aspida were found in the cytoplasm of many hosts, and the number of parasites infection-1 was directly related to infection level. Parasite prevalence averaged 24.0 and 11.5% with mean number of parasites infection-1 being 1.5 and 1.3 for Chesapeake Bay and Indian River samples, respectively. D. aspida was estimated to remove up to 68% of host standing stock d-1 with a mean of 10% for all samples. The average impact of parasitism on F. panamensis populations was somewhat less than would be expected from copepod grazing.  相似文献   
79.
In this study a direct interaction of a metabolite of 3,4,3′,4′-tetrachlorobiphenyl with transthyretin (prealbumin) was observed, leading to reduced plasma levels of retinol, RBP and thyroxin in rats and mice.  相似文献   
80.
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