337 research outputs found

    Loss of plant biodiversity eliminates stimulatory effect of elevated CO2 on earthworm activity in grasslands

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    Earthworms are among the world's most important ecosystem engineers because of their effects on soil fertility and plant productivity. Their dependence on plants for carbon, however, means that any changes in plant community structure or function caused by rising atmospheric CO2 or loss of plant species diversity could affect earthworm activity, which may feed back on plant communities. Production of surface casts measured during three consecutive years in field experimental plots (n=24, 1.2m2) planted with local calcareous grassland species that varied in plant species richness (diversity levels: high, 31 species; medium, 12; low, 5) and were exposed to ambient (356μl CO2 l−1) or elevated (600μl CO2 l−1) CO2 was only consistently stimulated in high diversity plots exposed to elevated CO2 (+120%, 31 spp: 603±52 under ambient CO2 vs. 1,325±204g cast dwt. m−2year−1 under elevated CO2 in 1996; +77%, 940±44 vs. 1,663±204g cast dwt. m−2year−1 in 1998). Reductions in plant diversity had little effect on cast production in ecosystems maintained at ambient CO2, but the stimulatory effect of elevated CO2 on cast production disappeared when plant species diversity was decreased to 12 and 5 species. High diversity plots were also the only communities that included plant species that an earlier field study showed to be among the most responsive to elevated CO2 and to be most preferred by earthworms to deposit casts near. Further, the +87% CO2-induced increase in cast production measured over the 3years corresponded to a parallel increase in cumulative total nitrogen of 5.7gNm−2 and would help explain the large stimulation of aboveground plant biomass production observed in high-diversity communities under elevated CO2. The results of this study demonstrate how the loss of plant species from communities can alter responses of major soil heterotrophs and consequently ecosystem biogeochemistr

    Who were the voters behind the Schulz effect? An analysis of voter trajectories in the run-up to the 2017 German federal election

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    In early 2017, after the nomination of Martin Schulz as candidate for chancellor, the SPD experienced a rapid surge in public support as measured in public opinion polls. Yet, the upward trend proved short-lived and the SPD ended up with the worst election result since 1949. Using data from a multi-wave panel survey, this analysis examines the voting trajectories of eight thousand German citizens over the course of one year in order to investigate the processes underlying the so called ‘Schulz effect’. The voter trajectories show that the surge and decline of public support for the SPD was accompanied by some reshuffling in the composition of its electorate. Moreover, different explanations of the party’s swaying in the polls are tested, showing that the SPD achieved the activation of dormant party identifiers but attracted and then lost other voters with diverse characteristics and policy preferences

    When who and how matter: explaining the success of referendums in Europe

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    This article aims to identify the institutional factors that make a referendum successful. This comparative analysis seeks to explain the success of top-down referendums organized in Europe between 2001 and 2013. It argues and tests for the main effect of three institutional factors (popularity of the initiator, size of parliamentary majority, and political cues during referendum campaigns) and controls for the type of referendum and voter turnout. The analysis uses data collected from referendums and electoral databases, public opinion surveys, and newspaper articles. Results show that referendums proposed by a large parliamentary majority or with clear messages from political parties during campaign are likely to be successful

    How Quickly We Forget: The Duration of Persuasion Effects From Mass Communication

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    Scholars do not usually test for the duration of the effects of mass communication, but when they do, they typically find rapid decay. Persuasive impact may end almost as soon as communication ends. Why so much decay? Does mass communication produce any long-term effects? How should this decay color our understanding of the effects of mass communication? We examine these questions with data from the effects of advertising in the 2000 presidential election and 2006 subnational elections, but argue that our model and results are broadly applicable within the field of political communication. We find that the bulk of the persuasive impact of advertising decays quickly, but that some effect in the presidential campaign endures for at least 6 weeks. These results, which are similar in rolling cross-section survey data and county-level data on actual presidential vote, appear to reflect a mix of memory-based processing (whose effects last only as long as short-term memory lasts) and online processing (whose effects are more durable). Finally, we find that immediate effects of advertising are larger in subnational than presidential elections, but decay more quickly and more completely. [Supplementary material is available for this article. Go to the publisher's online edition of Political Communication for the following free supplemental resource(s): discussion of methodological issues; results for a alternative specifications of key models; full reports of model results.]. © 2013 Copyright Taylor & Francis Group, LLC

    Using Search Query Surveillance to Monitor Tax Avoidance and Smoking Cessation following the United States' 2009 “SCHIP” Cigarette Tax Increase

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    Smokers can use the web to continue or quit their habit. Online vendors sell reduced or tax-free cigarettes lowering smoking costs, while health advocates use the web to promote cessation. We examined how smokers' tax avoidance and smoking cessation Internet search queries were motivated by the United States' (US) 2009 State Children's Health Insurance Program (SCHIP) federal cigarette excise tax increase and two other state specific tax increases. Google keyword searches among residents in a taxed geography (US or US state) were compared to an untaxed geography (Canada) for two years around each tax increase. Search data were normalized to a relative search volume (RSV) scale, where the highest search proportion was labeled 100 with lesser proportions scaled by how they relatively compared to the highest proportion. Changes in RSV were estimated by comparing means during and after the tax increase to means before the tax increase, across taxed and untaxed geographies. The SCHIP tax was associated with an 11.8% (95% confidence interval [95%CI], 5.7 to 17.9; p<.001) immediate increase in cessation searches; however, searches quickly abated and approximated differences from pre-tax levels in Canada during the months after the tax. Tax avoidance searches increased 27.9% (95%CI, 15.9 to 39.9; p<.001) and 5.3% (95%CI, 3.6 to 7.1; p<.001) during and in the months after the tax compared to Canada, respectively, suggesting avoidance is the more pronounced and durable response. Trends were similar for state-specific tax increases but suggest strong interactive processes across taxes. When the SCHIP tax followed Florida's tax, versus not, it promoted more cessation and avoidance searches. Efforts to combat tax avoidance and increase cessation may be enhanced by using interventions targeted and tailored to smokers' searches. Search query surveillance is a valuable real-time, free and public method, that may be generalized to other behavioral, biological, informational or psychological outcomes manifested online

    Disgust Sensitivity and the Neurophysiology of Left- Right Political Orientations

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    Disgust has been described as the most primitive and central of emotions. Thus, it is not surprising that it shapes behaviors in a variety of organisms and in a variety of contexts—including homo sapien politics. People who believe they would be bothered by a range of hypothetical disgusting situations display an increased likelihood of displaying right-of-center rather than left-of-center political orientations. Given its primal nature and essential value in avoiding pathogens disgust likely has an effect even without registering in conscious beliefs. In this article, we demonstrate that individuals with marked involuntary physiological responses to disgusting images, such as of a man eating a large mouthful of writhing worms, are more likely to self-identify as conservative and, especially, to oppose gay marriage than are individuals with more muted physiological responses to the same images. This relationship holds even when controlling for the degree to which respondents believe themselves to be disgust sensitive and suggests that people’s physiological predispositions help to shape their political orientations

    The Stakes in Bayh-Dole: Public Values Beyond the Pace of Innovation

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    Evaluation studies of the Bayh-Dole Act are generally concerned with the pace of innovation or the transgressions to the independence of research. While these concerns are important, I propose here to expand the range of public values considered in assessing Bayh-Dole and formulating future reforms. To this end, I first examine the changes in the terms of the Bayh-Dole debate and the drift in its design. Neoliberal ideas have had a definitive influence on U.S. innovation policy for the last thirty years, including legislation to strengthen patent protection. Moreover, the neoliberal policy agenda is articulated and justified in the interest of “competitiveness.” Rhetorically, this agenda equates competitiveness with economic growth and this with the public interest. Against that backdrop, I use Public Value Failure criteria to show that values such as political equality, transparency, and fairness in the distribution of the benefits of innovation, are worth considering to counter the “policy drift” of Bayh-Dole
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