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Groups involved in the livestock vs large carnivore conflict hold widely divergent attitudes toward carnivores, yet they all endorse general ecocentric values. The hypothesis that contrasting motives for the endorsement of ecocentric values may mediate between the general values and attitudes toward carnivores was evaluated in a survey among sheep farmers, wildlife managers, and research biologists in Norway. Results showed positive associations between anthropocentrism and negative attitudes toward carnivores, and between ecocentrism and positive attitudes toward carnivores for all three groups. Farmers, relative to the other groups, scored lowest on the ecocentric and highest on the anthropocentric subscales, as operationalized by Thompson and Barton (1994). This result may be interpreted within a cognitive hierarchy model where environmental beliefs may transform general ecocentric values into negative or positive attitudes toward one specific environmental category.  相似文献   
33.
The present work aims at identification of multiple drug-resistant pathogenic bacteria in a selected stretch, namely, Puri on the Bay of Bengal, India. Six stations at the coast of Puri were selected and samples of water and sediment were collected during the winter of 2008 and 2009 for this study. Thirty-eight pathogenic bacteria were isolated and identified from both the water and the sediment of 6 fixed stations (PU-1a, PU-1b, PU-2, PU-3, PU-4, and PU-5). The identified pathogens were Escherichia coli, Vibrio cholerae, Vibrio parahaemolyticus, Klebsiella pneumoniae, Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, and Proteus mirabilis. Antibiotic sensitivity of the isolated bacteria was studied by using 12 selected antibiotics, commonly used for the medication of human beings and animals. The isolated pathogens from both the water and the sediment samples showed lowest resistance to chloramphenicol (C-30 μg) where as the pathogens showed highest level of resistance to ampicillin (10-μg) among the antibiotics used for the study. Among the isolated pathogens E. faecalis (PU-1a), P. aeruginosa (PU-2 and PU-3), E. coli (PU-3 and PU-4), and K. pneumonia (PU-4) showed resistance to more than four antibiotics. Out of the isolated species, 57.8% pathogens were multi-drug resistant. Antibiotic resistance indexes of all the stations were calculated and found to be in the range of 0.066 to 0.083.  相似文献   
34.
Endosulfan, malathion, and phosphamidon are widely used pesticides. Subchronic exposure to these contaminants commonly affects the central nervous system, immune, gastrointestinal, renal, and reproductive system. There effects have been attributed to increased oxidative stress. This study was conducted to examine the role of oxidative stress in genotoxicity following pesticide exposure using peripheral blood mononuclear cells (PBMC) in vitro. Further possible attenuation of genotoxicity was studied using N-acetylcysteine (NAC) and curcumin as known modulators of oxidative stress. Cultured mononuclear cells was isolated from peripheral blood of healthy volunteers, and exposed to varying concentrations of different pesticides: endosulfan, malathion, and phosphamidon for 6, 12, and 24 h. Lipid peroxidation was assessed by cellular malondialdehyde (MDA) level and DNA damage was quantified by measuring 8-hydroxy-2'-deoxyguanosine (8-OH-dG) using ELISA. Both MDA and 8-OH-dG were significantly increased in a dose-dependent manner following treatment with these pesticides. There was a significant decrease in MDA and 8-OH-dG levels in PBMC when co-treated with NAC or/and curcumin as compared to pesticide alone. These results indicate that pesticide-induced oxidative stress is probably responsible for the DNA damage, and NAC or curcumin attenuate this effect by counteracting the oxidative stress.  相似文献   
35.
Petroleum hydrocarbon (PHC) concentration was monitored in water of estuaries, ports, and coastal transects up to 10-km distance in East Coast of India once in every year during 2002–2009. The highest concentration was observed at Haldia port (1.60–20.11 μg/l) due to the impact of hydrocarbon discharges from nearby oil refinery, petrochemical industries, handling of crude oils, etc. The concentration of PHC exhibited relatively higher values during low tide than the high tide in all the four estuaries indicating riverine inputs and land-based discharges, which contribute substantial amounts of PHC to the coastal water. Hoogly estuary recorded higher values of PHC (1.17–18.50 μg/l) due to the influence of industrial wastes, land runoff, and port activities. The spatial distribution of PHC estimated by the kriging method showed a variation in concentration of PHC over the whole region. To discriminate the dispersion pattern of PHC, principal component analysis (PCA) was performed using a correlation matrix.  相似文献   
36.
Water contamination by non-steroidal anti-inflammatory drugs, such as acetaminophen, is an emerging ecological concern. In this study, a new three-dimensional manganese dioxide-engrafted reduced graphene oxide (3D MnO2/rGO) hybrid aerogel was developed for acetaminophen sequestration. The synthesis involved firstly the self-assembly of GO aerogel, followed by thermal reduction and in-situ MnO2 growth by redox-reaction. The aerogel demonstrated interlinked planes with smooth surfaces deposited with MnO2 nanospheres and pores of 138.4 – 235.3 µm width. The influences of adsorbent dosage, initial pH, acetaminophen concentration, temperature and contact time were investigated. It was determined that the adsorption of acetaminophen occurred on uniform sorption sites in the aerogel, as suggested by the best fit of data to the Langmuir isotherm, yielding a maximum adsorption capacity of 252.87 mg/g. This highest adsorption performance of the 3D MnO2/rGO aerogel was attained at a dosage of 0.6 g/L, initial pH of 6.2 and temperature of 40°C. The process kinetics were in-line with the pseudo-first-order and pseudo-second-order kinetics at 10 and 20 – 500 mg/L concentrations, respectively. Thermodynamic assay showed the spontaneity and endothermicity features of the 3D MnO2/rGO-acetaminophen system. The acetaminophen adsorption mechanisms were mainly hydrogen bonding and pore entrapment. Moreover, the as-synthesised aerogel was effectively regenerated using acetone and re-utilised in four adsorption-desorption cycles. Overall, the results highly recommend the implementation of the 3D MnO2/rGO hybrid aerogel for purification of wastewater polluted by acetaminophen residue.  相似文献   
37.
地基不均匀沉降可能会引起沉降范围内部分隔震支座发生转动,造成隔震层刚度发生变化,进而导致上部结构地震损伤和失效风险增大。针对地基不均匀沉降条件下基础隔震结构地震响应研究,现有成果大都通过施加平动位移进行模拟,并未考虑隔震支座转角的不利影响。为了研究地基不均匀沉降条件下基础隔震结构支座可能出现的转动及其对整体结构地震响应特征影响规律,首先以隔震支座为对象,研究了支座转动变形与叠层橡胶隔震支座水平刚度变化关系,建立了叠层橡胶隔震支座转角与水平刚度变化关系函数;在此基础上系统研究了地基不均匀沉降条件下整体基础隔震结构响应特征,以及基础结构的减震系数变化规律,以期揭示地基不均匀沉降对基础隔震结构地震响应影响机理。结果表明:隔震支座转角变形会引起隔震结构体系地震响应发生显著变化,随着隔震支座转角增大,隔震层水平刚度增大的同时隔震结构体系变形能力减弱,进而造成上部结构加速度响应增大,位移响应减小,导致基础隔震结构水平减震系数增大,减震效果低于预期;当转角接近π/2 时,隔震支座将丧失降低上部结构地震响应的作用,原隔震结构将退化为抗震结构;对于存在地基不均匀沉降的基础隔震结构,应及时采取必要措施控制地震响应,以防范上部结构发生倾覆。  相似文献   
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