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Levine  Adam Seth  Kline  Reuben 《Climatic change》2017,142(1-2):301-309

Many scholars study when climate change communication increases citizen engagement. Yet, past work has largely used public opinion-based measures of engagement to evaluate alternative frames. In this paper, we argue for a new approach to evaluation, which is premised on research on the policy-making process showing that space on the political agenda and, ultimately, policy change are more likely to arise in response to changes in both public opinion and collective political action. Thus, we argue that alternative frames should be evaluated based on their consequences for both. This is especially critical given that frames can have divergent effects on attitudes and behavior. Using a combination of field and survey experiments, we apply our approach to evaluate two frames related to climate change risks. We find that they heighten people’s concern about climate change yet decrease their rate of political action to express that concern. Our results suggest caution with regard to these frames in particular and that, more generally, frames that might seem advantageous when examining public opinion may not be when political behavior is analyzed.

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An experiment was conducted to determine if a tailings substrate would inhibit recolonization of benthic macrofauna upon closure of a submarine tailings disposal (STD) operation. Trays of defaunated marine sediment, serving as a reference, and trays of tailings from a proposed gold mine were placed at 21 m depth on the ocean floor to allow colonization via settlement from the water column. Trays of reference sediment and tailings, and cores of ambient sediment were collected 9, 17, and 22 months after tray placement. Probable tray effects, which were desirable given the objectives of this study, precluded direct comparison of ecological succession in the tray sediments to the ambient assemblage. The ambient macrofauna assemblage was distinguishable from the reference sediment and tailings assemblages throughout the experiment and displayed more pronounced seasonality. Differences between the reference sediment and tailings assemblages were generally insignificant, including total abundance, total biomass, number of taxa, average size of individuals, numerically dominant taxa, abundance by ecological guilds, and overall community composition. Upon cessation of STD, recolonization of a benthic macrofauna community should not be inhibited by the presence of these tailings as a benthic substrate.  相似文献   
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This study applied the loss after combustion (LAC) method and the acid decalcification (ADC) method to quantify different components of an excavating sponge. Samples of dried coral skeleton of Favia sp. invaded by the Indo‐Pacific excavating sponge Cliona orientalis Thiele, 1900 were used. The sponge tissue penetrated the 12‐mm‐thick samples to approximately 10 mm. The average proportional weight of organic matter, siliceous spicules, calcareous substrate and salts in the entire samples was found to be respectively 2.5%, 4.4%, 90.5% and 2.5% of dry weight applying the LAC method, and 2.9%, 5.9%, 89.0% and 2.3% of dry weight applying the ADC method. Respective volumetric proportions of the organic matter, spicules, substrate and salts were then calculated to be 6.4%, 5.5%, 85.2% and 3.0% of volume with the LAC method, and 7.4%, 7.2%, 82.7% and 2.7% of volume with the ADC method. The LAC method showed low variability of data and is simple and fast and therefore is recommended. The ADC method generated very similar results to the LAC method. However, due to the handling involved in the ADC method, more than half of the spicules may be lost and the method is therefore not recommended unless careful data corrections are considered. In addition, the buoyant weight method was used to quantify actual substrate weight in the fresh sponge‐substrate samples. This method was found to be at least 97% effective, revealing that buoyant weights can potentially be used to quantify bioerosion rates of excavating sponges. To our knowledge, this is the first study to systemically quantify organic and inorganic components of an excavating sponge and its calcareous substrate, providing improved standard methods for future studies.  相似文献   
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Attempts to predict which geographic areas should be associated with a high percentage of homes with unusually high indoor radon levels in Virginia and Maryland have been based on estimates of soil radon and soil permeability for geological units. This method is found to be less successful and probably less cost-effective than the use of total-gamma aeroradioactivity maps.  相似文献   
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Stress proteins (heat shock proteins, hsps) form part of the cellular protein repair system, and are induced by a wide variety of Stressors. To determine their suitability as tools for assessing sublethal sediment toxicity, we measured levels of members of the stress protein families hsp60 and hsp70 in benthic estuarine amphipods (Ampelisca abdita) exposed to sediments from 23 different sampling sites in San Francisco Bay for 10 d. Concentrations of sediment-associated xenobiotics were determined. Per cent survival was recorded and surviving animals were analysed for stress proteins using western blotting techniques. An inverse correlation (r2 = 0.44) was seen between amphipod survival and hsp64 levels, and hsp64 levels were positively correlated with concentrations of total polycyclic aromatic hydrocarbons (PAHs) (r2 = 0.5). Principal component analysis revealed that amphipod mortality was linked to a combination of several PAHs (phenanthrene, fluoranthene, pyrene, benzo(a)pyrene) and di-n-butylphthalate at southern San Francisco Bay sites. At northern San Francisco Bay sites, negative correlations were found between hsp64 levels and organotin compounds (MBT, DBT, TBT), and between hsp71 levels and the PAHs, benzo (b,k)fluoranthene and benzo(G,H,I)perylene, suggesting an inhibitory effect of these compounds on stress protein expression.  相似文献   
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A stratified sedimentary and archaeological sequence over seven meters thick is under investigation on Upper Shawnee Island in the Upper Delaware Valley, Monroe County, Pennsylvania. Artifact deposits identified to date include Early Archaic (7380 B.C.), possible Middle Archaic (4300/3300 B.C.), Late Archaic (1565 B.C.), and Middle and Late Woodland components. This paper focuses on the Early Archaic deposits at approximately 4.3 meters below the surface and the implications that the entire profile has for paleoenvironmental change. The sedimentary sequence represents several major changes in depositional processes. Of special interest is a dramatic decrease in landscape stability and an increase in flood depositions during the mid-Holocene, circa 4300/3300 B.C. Similar changes are evident at archaeological sites in the Middle and Lower sections of the Delaware Valley and appear to be a reflection of regional climatic change.  相似文献   
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The National Ignition Facility (NIF) is capable of creating new and novel high-energy-density (HED) systems relevant to astrophysics. Specifically, a system could be created that studies the effects of a radiative shock on a hydrodynamically unstable interface. These dynamics would be relevant to the early evolution after a core-collapse supernova of a red supergiant star. Prior to NIF, no HED facility had enough energy to perform this kind of experiment. The experimental target will include a 340 ??m predominantly plastic ablator followed by a low-density SiO2 foam. The interface will have a specific, machined pattern that will seed hydrodynamic instabilities. The growth of the instabilities in a radiation-dominated environment will be observed. This experiment requires a ??300?eV hohlraum drive and will be diagnosed using point projection pinhole radiography, which have both been recently demonstrated on NIF.  相似文献   
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