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The purpose of this study was to estimate the total medical care costs of individuals injured in motor vehicle crashes and in crashes where alcohol was involved. Crashes were studied that involved 2,728 vehicle occupants and 191 pedestrians with injuries as reported in 1979 by the National Accident Sampling System, a probability sample of all motor vehicle crashes occurring in the united States. Medical care costs were assigned by using Abbreviated Injury Scale codes in accordance with other published research. Determination of alcohol involvement was based on crash characteristics. Results indicate that 20.2 % of medical care costs for motor vehicle crash injuries may be due to crashes where alcohol was involved. It was estimated that alcohol-related motor vehicle crashes cost between $434 million and $483 million in medical care alone in the United States in 1979.  相似文献   
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Two experiments examined clinical validation's ability to increase examination of a persuasive message and increase long-term recycling. In Experiment 1, validating (acknowledging) recycling's inconvenience decreased criticism of the persuasive message, supporting validation's ability to reduce reactance and open the reader to new ideas. Validation did not improve attitudes towards the sign's author, removing liking for the communicator as an alternate explanation for attitude change. In Experiment 2, different recycling signs were created from a 2(no validation/validation) by 2(weak/strong arguments) factorial design, and placed in university buildings. The validation weak sign increased recycling more than the validation strong sign, especially after the signs were removed. We suggest that validation induced people to scrutinize the weak message and use their existing pro-recycling attitudes to “creatively elaborate” it. Discussion emphasizes clinical validation and the Elaboration Likelihood Model as theoretical tools, as well as the potential for thought provoking signs to have long-term effects.  相似文献   
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Integrity of chloroplast membranes is essential to photosynthesis. Loss of thylakoid membrane integrity has been proposed as a consequence of ozone (O(3)) exposure and therefore may be a mechanistic basis for decreased photosynthetic rates commonly associated with ozone exposure. To investigate this hypothesis, Pinus ponderosa seedlings were exposed to ambient air or ozone concentrations maintained at 0.15 or 0.30 microliter l(-1) for 10 h day(-1) for 51 days during their second growing season. Over the course of the study, foliage samples were periodically collected for thylakoid membrane, chlorophyll and protein analyses. Additionally, gas-exchange measurements were made in conjunction with foliage sampling to verify that observed chloroplastic responses were associated with ozone-induced changes in photosynthesis.Needles exposed to elevated ozone exhibited decreases in chlorophyll a and b content. The decreases were dependent on the duration and intensity of ozone exposure. When based on equal amounts of chlorophyll, ozone-exposed sample tissue exhibited an increase in total protein. When based on equal amounts of protein, ozone-exposed samples exhibited an increase in 37 kDa proteins, possibly consisting of breakdown products, and a possible decrease in 68 kDa proteins, Rubisco small subunit. There was also a change in the ratio of Photosystem I protein complexes CPI and CPII that may have contributed to decreased photosynthesis. Net photosynthetic rates were decreased in the high ozone treatment suggesting that observed structural and biochemical changes in the chloroplast were associated with alterations of the photosynthetic process.  相似文献   
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The southern Africa crisis represents the first widespread emergency in a region with a mature HIV/AIDS epidemic. It provides a steep learning curve for the international humanitarian system in understanding and responding to the complex interactions between the epidemic and the causes and the effects of this crisis. It also provoked much debate about the severity and causes of this emergency, and the appropriateness of the response by the humanitarian community. The authors argue that the over-emphasis on food aid delivery occurred at the expense of other public health interventions, particularly preventative and curative health services. Health service needs were not sufficiently addressed despite the early recognition that ill-health related to HIV/AIDS was a major vulnerability factor. This neglect occurred because analytical frameworks were too narrowly focused on food security, and large-scale support to health service delivery was seen as a long-term developmental issue that could not easily be dealt with by short-term humanitarian action. Furthermore, there were insufficient countrywide data on acute malnutrition, mortality rates and performance of the public health system to make better-balanced evidence-based decisions. In this crisis, humanitarian organisations providing health services could not assume their traditional roles of short-term assistance in a limited geographical area until the governing authorities resume their responsibilities. However, relegating health service delivery as a long-term developmental issue is not acceptable. Improved multisectoral analytical frameworks that include a multidisciplinary team are needed to ensure all aspects of public health are dealt with in similar future emergencies. Humanitarian organisations must advocate for improved delivery and access to health services in this region. They can target limited geographical areas with high mortality and acute malnutrition rates to deliver their services. Finally, to address the underlying problem of the health sector gap, a long-term strategy to ensure improved and sustainable health sector performance can only be accomplished with truly adequate resources. This will require renewed efforts on part of governments, donors and the international community. Public health interventions, complementing those addressing food insecurity, were and are still needed to reduce the impact of the crisis, and to allow people to re-establish their livelihoods. These will increase the population's resilience to prevent or mitigate future disasters.  相似文献   
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It has been reported that the relative response factors of isotopically labeled standards and unlabeled standards of the same perfluorinated compounds could be different. Individual (100 ng mL?1) solutions of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) were analyzed using high-performance liquid chromatography tandem mass-spectrometry under negative-ion electrospray to detect any impurities present down to 0.5%–0.1% relative to the major component. Purity of the standards ranged from approximately 86% to ≥ 97%. Standard solutions of unlabeled and isotopically labeled materials were analyzed to compare the response factors of isotopically labeled analytes versus their nonlabeled counterparts in three different matrices at equivalent concentrations: organic solvent (methanol), serum extract, and water present individually and concurrently. Not all labeled analytes have the same response factor as their nonlabeled complement, and in at least one case the matrix in which the standard is present may cause significant suppression of response. Standard solutions of electrochemical fluorination produced PFOA and PFOS were quantified under multiple reaction monitoring mode, using calibration curves prepared from standards consisting primarily of linear standards only. The use of linear only standards may cause under-prediction of concentrations, and that the working range of these standards may be limited.  相似文献   
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•Addition of hindered amine increased thermal stability and viscosity of TTTM. •Addition of hindered amine improved the CO2 absorption performance of TTTM. •Good the CO2 absorption of recycled solvents after two regenerations. •Important role of amine group in CO2 absorption of TTTM confirmed by DFT analysis. Is it possible to improve CO2 solubility in potassium carbonate (K2CO3)-based transition temperature mixtures (TTMs)? To assess this possibility, a ternary transition-temperature mixture (TTTM) was prepared by using a hindered amine, 2-amino-2-methyl-1,3-propanediol (AMPD). Fourier transform infrared spectroscopy (FT-IR) was employed to detect the functional groups including hydroxyl, amine, carbonate ion, and aliphatic functional groups in the prepared solvents. From thermogravimetric analysis (TGA), it was found that the addition of AMPD to the binary mixture can increase the thermal stability of TTTM. The viscosity findings showed that TTTM has a higher viscosity than TTM while their difference was decreased by increasing temperature. In addition, Eyring’s absolute rate theory was used to compute the activation parameters (ΔG*, ΔH*, and ΔS*). The CO2 solubility in liquids was measured at a temperature of 303.15 K and pressures up to 1.8 MPa. The results disclosed that the CO2 solubility of TTTM was improved by the addition of AMPD. At the pressure of about 1.8 MPa, the CO2 mole fractions of TTM and TTTM were 0.1697 and 0.2022, respectively. To confirm the experimental data, density functional theory (DFT) was employed. From the DFT analysis, it was found that the TTTM+ CO2 system has higher interaction energy (|ΔE |) than the TTM+ CO2 system indicating the higher CO2 affinity of the former system. This study might help scientists to better understand and to improve CO2 solubility in these types of solvents by choosing a suitable amine as HBD and finding the best combination of HBA and HBD.  相似文献   
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