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241.
Introduction. Cooling of the body is used to treat hyperthermic individuals with heatstroke or to depress core temperature below normal for neuroprotection. A novel, chemically activated, unpowered cooling device, CAERvest®, was investigated for safety and efficacy. Methods. Eight healthy male participants (body mass 79.9?±?1.9?kg and body fat percentage 16.1?±?3.8%) visited the laboratory (20 °C, 40% relative humidity) on four occasions. Following 30-min rest, physiological and perceptual measures were recorded. Participants were then fitted with the CAERvest® proof of concept (PoC) or prototype 1 (P1), 2 (P2) or 3 (P3) for 60 min. Temperature, cardiovascular and perceptual measures were recorded every 5 min. After cooling, the CAERvest® was removed and the torso checked for cold-related injuries. Results. Temperature measures significantly (p?Conclusion. This study demonstrates that the CAERvest® is an effective device for reducing body temperature in healthy normothermic individuals without presence of cold injury. Further research in healthy and clinical populations is warranted.  相似文献   
242.
The application of direct-flame incineration to successfully eliminate a smoke-oil-mist and odor problem in the manufacture of rubber-base rug underlay, is presented. The investigation of various air pollution control processes leading to the development and adoption of the direct-flame incineration system, is covered. The rug-underlay curing process incorporating the direct-flame incineration system with primary heat recovery is described. Results and discussion of a source test to determine the effectiveness of direct-flame incineration in this application are included.  相似文献   
243.
A feasible and relatively readily available analytical method was adapted for the assessment of alcohol ethoxylates (AE) and fatty alcohols (FA) in sediments. This study illustrates the simultaneous measurement of 38 of 114 possible alcohol ethoxylate ethoxymers (AE) and fatty alcohols (FA) found in commercially important AE products. We predicted toxicity for all identified fractions, as well as the total mixture toxicity, relative to three exposure scenarios via sewage treatment plants (STP) for these widely used chemicals in consumer products and hence generate a preliminary environmental risk screening for AE and FA in sediments. The method is based on derivatization of solvent or solid-phase extracts with 2-fluoro-N-methylpyridinium p-toluenesulfonate (Pyr+). The derivatized extracts were analyzed with liquid chromatography/mass spectrometry (LC/MS) operating in the positive ion electrospray mode. The extraction efficiency of AE and FA in three different sediments of varying composition was evaluated with spike-recovery studies, ranging from 64% to 80%. The detection limits for individual ethoxymers typically ranged from 1 to 5ngg−1on a dry weight basis. The mean limit of detection (LOD) was 6ngg−1and the median LOD was 3ngg−1. AE and FA in sediments were found to be stable for two weeks if preserved with 3% (v/v) formalin and stored at 4–6C. Based on equilibrium partitioning, background concentrations of AE and FA were predicted to be below concentrations known to elicit chronically toxic effects. Total worst case mixture toxicities for all AE ethoxymers combined with FA were predicted to result in a risk quotient less than 0.6. Activated sludge treatment (STP) significantly reduced the release of total AE and FA by four-fold, suggesting that the total mixture risk quotient would be < 0.15 for sediment dependent organisms.  相似文献   
244.
ABSTRACT

How can theories of affect and felt emotions be useful in studying the communication of environmental crises? Beginning from tears spilt over a graph of transgressed planetary boundaries published in an academic paper, this article explores the presentation in graphic visual forms of affective imagery and a growing sophistication amongst scientists, policymakers and activist communicators in the visualization of information, data and stories employed to carry the often difficult and complex messages of current earth systems crises. Critically, this article attends to the “emotion work” of such images. Taking a lead from cultural sociology and attempting to elucidate the relationship between societies under pressure and its choice of texts, this article considers the environmental documentary Cowspiracy [Anderson, K., & Kuhn, K. (2014). Cowspiracy. San Francisco, CA: AUM Films & First Spark Media.] to ask questions of affect’s relation to expressions of the earth systems crisis, which is also a crisis of culture.  相似文献   
245.
One unexplored area in sexual conflict studies is the female physiological costs and possible resource reallocation that accompany evolutionary costs due to male harassment. Using females of the damselfly Hetaerina americana, I first investigated whether male harassment affected female mating rate and survival and explored whether such effects induced a resource allocation from immunity (in the form of phenoloxidase activity) and muscular fat reserves to egg number and size. Using two seasons that differed in male harassment, it was found that the higher the male harassment, the fewer are the female matings and the lower is the female survival. These results were corroborated using an experimental approach in which a situation of high male harassment was induced. It was also found that when the first mating takes place and at high male harassment, females had more reduced phenoloxidase activity and fat reserves and tended to lay most of the eggs they produce in their lifetime and these were considerably large. However, at low male harassment, egg number and size were more equally produced across matings. Females under high male harassment seemed to suffer the survival costs but may show a plastic evolutionary response of reallocating resources to egg traits to maximize fitness.  相似文献   
246.
Environmental Science and Pollution Research - In the recent past, partial replacement of cement by rice husk ash (RHA) in concrete is a prime focus of global researchers for sustainable...  相似文献   
247.
Landfill cover soils oxidize a considerable fraction of the methane produced by landfilled waste. Despite many efforts this oxidation is still poorly quantified. In order to reduce the uncertainties associated with methane oxidation in landfill cover soils, a simulation model was developed that incorporates Stefan-Maxwell diffusion, methane oxidation, and methanotrophic growth. The growth model was calibrated to laboratory data from an earlier study. There was an excellent agreement between the model and the experimental data. Therefore, the model is highly applicable to laboratory column studies, but it has not been validated with field data. A sensitivity analysis showed that the model is most sensitive to the parameter expressing the maximum attainable methanotrophic activity of the soil. Temperature and soil moisture are predicted to be the environmental factors affecting the methane oxidizing capacity of a landfill cover soil the most. Once validated with field data, the model will enable a year-round estimate of the methane oxidizing capacity of a landfill cover soil.  相似文献   
248.
In the present study, the impact of sodium metabisulphite (Na2S2O5), a food preservative, on seed germination, growth and yield of Vigna sinensis, Savi has been evaluated. Observations clearly reveal the deleterious effect of Na2S2O5 on germination, stomatal development, stomatal index, chlorophyll content and yield. The shoot length exhibited a steady rise in length, while the biomass showed a gradual decrease with the increasing doses of Na2S2O5.  相似文献   
249.
This study investigates the mechanisms controlling the distribution of 3-bromo-2,2-bis(bromomethyl)propanol (TBNPA) and 2,2-bis(bromomethyl)propan-1,3-diol (DBNPG) in a fractured chalk aquitard. An extensive monitoring program showed a systematic decrease in the TBNPA/DBNPG ratio with distance from the contamination source. Sorption of TBNPA on the white and/or gray chalks comprising the aquitard is approximately one order of magnitude greater than that of DBNPG. This results in more efficient removal of TBNPA from the fracture into the porous matrix and thus decreases the TBNPA/DBNPG ratio in the fracture water. Mathematical modeling of solute transport in the fracture domain illustrates the probable importance of sorption in controlling the spatial variation in TBNPA and DBNPG ratio.  相似文献   
250.
The role of nature documentaries in shaping public attitudes and behavior toward conservation and wildlife issues is unclear. We analyzed the emotional content of over 2 million tweets related to Our Planet, a major nature documentary released on Netflix, with dictionary and rule-based automatic sentiment analysis. We also compared the sentiment associated with species mentioned in Our Planet and a set of control species with similar features but not mentioned in the documentary. Tweets were largely negative in sentiment at the time of release of the series. This effect was primarily linked to the highly skewed distributions of retweets and, in particular, to a single negatively valenced and massively retweeted tweet (>150,000 retweets). Species mentioned in Our Planet were associated with more negative sentiment than the control species, and this effect coincided with a short period following the airing of the series. Our results are consistent with a general negativity bias in cultural transmission and document the difficulty of evoking positive sentiment, on social media and elsewhere, in response to environmental problems.  相似文献   
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