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31.
32.
A series of hypotheses on the role of the individual administrator in famine relief are proposed and three are examined with respect to case studies of famines in India (1896 and 1906–1907), Uganda (1908) and Lombok (1940). While the evidence is not conclusive, the focus upon the role of the individual administrator offers additional insights into the compexities of official response to famines.  相似文献   
33.
This paper extends prior research on risk perceptions in the West to the Hong Kong Chinese context by studying the nature of the responses of 229 Hong Kong Chinese to an adapted environmental appraisal inventory (EAI-C), which consisted of three scales with one related to the self and the other two related to the local and global environments, respectively. Results lent support to a local–global dichotomy: hazards were appraised to be more threatening in the global than the local context. Responses to the three-scale adaptation were factor analysed and three subscales were extracted for each of the EAI scales. As with findings reported in a previous study with an Irish sample, the subscales could be considered to represent techno-human, everyday-life and natural hazards. Results also indicated that Hong Kong Chinese appraised environmental hazards as more threatening than did Western samples surveyed in prior studies. This was most striking when hazards were appraised in relation to the self. Similar findings have also been reported in recent studies with Japanese samples. It was suggested that the accentuated threat to self observed in the current study might stem from a heightened sensitivity to environmental hazards in the Chinese people, which is determined by self-construction processes specific to Asian cultures. Using the EAI as a measurement for hazard appraisal may provide insights to how people from different cultures construe the impact of environmental hazards in various contexts.  相似文献   
34.
Experiments were conducted to determine the effect of nitrogen nutrition on the response of tobacco to ozone in the atmosphere. With Nicotiana rustica L., a noncommercial tobacco, plants receiving an “optimum” nitrogen supply were found to be more susceptible to ozone injury than those receiving deficient or luxury supplies. Furthermore, it was found on analyses of the third oldest tobacco leaf that, while these “optimum” plants showed little or no increase in respiration as a result of ozone in concentrations too low to produce visible injury, plants grown with deficient or excess nitrogen showed a significant increase in respiration under these same conditions. The increase in respiration was accompanied by a comparable and equally significant decrease in carbohydrate con-lent in the latter plants which was not apparent in plants at the “optimum” nitrogen supply, as well as an increase in total nitrogen, protein-nitrogen, and amino-acid nitrogen. In conclusion, it is suggested that the carbohydrate reserve built up in plants grown with deficient nitrogen nutrition serves as protection against the ozidative potential of ozone. Likewise, a decrease in carbohydrate content below that of “optimum” plants provides protection in plants grown with an overabundance of nitrogen fertilization, though possibly by a more complex mechanism.  相似文献   
35.
Abstract

Societal and governmental pressures to reduce diesel exhaust emissions are reflected in the existing and projected future heavy-duty certification standards of these emissions. Various factors affect the amount of emissions produced by a heterogeneous charge diesel engine in any given situation, but these are poorly quantified in the existing literature. The parameters that most heavily affect the emissions from compression ignition engine-powered vehicles include vehicle class and weight, driving cycle, vehicle vocation, fuel type, engine exhaust aftertreatment, vehicle age, and the terrain traveled. In addition, engine control effects (such as injection timing strategies) on measured emissions can be significant. Knowing the effect of each aspect of engine and vehicle operation on the emissions from diesel engines is useful in determining methods for reducing these emissions and in assessing the need for improvement in inventory models. The effects of each of these aspects have been quantified in this paper to provide an estimate of the impact each one has on the emissions of diesel engines.  相似文献   
36.
The remediation of the Thala Valley landfill, Casey Station, East Antarctica, is part of efforts to clean-up contaminated sites associated with the Australian Antarctic Program. These sites, ranging from abandoned rubbish dumps to fuel spills, are contaminated principally with metals and petroleum hydrocarbons. Remediation success depends on accurate, cost-effective and timely--fit-for-purpose--chemical analysis of soil and water samples from the site, which is required to guide excavation, the in situ or off-site treatment and disposal of contaminated material, and to validate satisfactory remediation. Owing to the remote location of Antarctica, it is necessary to carry out chemical analyses on-site. Waste and soil contaminated with Pb, Zn, Cd, and Cu were excavated from Thala Valley for removal to Australia, treatment and disposal. Analysis of total metal concentrations in soil was performed at Casey Station with a transportable energy dispersive X-ray fluorescence (EDXRF) spectrometer. Soil samples were prepared using a simple size-fractionation method to expedite sample throughput. A method for assessing contaminant mobility in solid waste (toxicity characteristic leaching procedure, TCLP) was also used to characterise soil. Although this was more labour-intensive and time-consuming than the total metals analysis, it was of great utility because leachable metals were often significant determinants in the assessment of contaminated soil. The combined data helped managers during remediation, directing excavation and allowing waste to be classified for treatment and disposal before its return to Australia.  相似文献   
37.
Although international trade in energy may offer a flexible and cost effective means by which European countries could meet their renewable energy targets, developers in the exporting nation can face local opposition for reasons which are not always clear. Using focus groups and a public survey, we contrast perspectives between local stakeholders and wind farm operators and investigate the community impacts associated with large-scale wind energy for domestic use and export from Ireland to the UK. Although the export of renewable energy from Ireland to the UK is currently on hold, our findings suggest that significant investment is required by the state and wind farm operators in better information provision, trust building, effective instruments to internalise wind farm externalities and co-management arrangements before Ireland can fully capture the benefits of wind exports to the UK.  相似文献   
38.
The known chemical basis of diverse avian eggshell coloration is generated by the same two classes of tetrapyrrole pigments in most living birds. We aimed to extend the evolutionary scope of these patterns by detecting pigments from extinct birds’ eggs. In our samples biliverdin was successfully extracted from subfossil shell fragments of the blue-green egg-laying upland moa Megalapteryx didinus, while protoporphyrin was extracted from the beige eggs of two other extinct moa species. Our data on pigment detection from eggshells of other extant paleognath birds, together with published information on other modern lineages, confirm tetrapyrroles as ubiquitous and conserved pigments contributing to diverse eggshell colours throughout avian evolution.  相似文献   
39.
The old saying, “what you don't know can't hurt you,” implies that ignorance is bliss. “A little knowledge is a dangerous thing,” may be closer to the truth; however, it is not the little that we know that is dangerous, but that which is not known. By design, the processes used in the chemical industry are reactive, and the intended reaction receives much scrutiny. However, other reactions occur, often unexpectedly, and possibly with severe consequences. The lessons we learn from these reactions must drive the improvement of our process development and technology management processes and the culture that shapes those processes, a culture of Technical Discipline.Technical Discipline, analogous to Operating Discipline in the manufacturing organization, is a culture committed to fully identifying and characterizing chemical and reaction hazards, and properly documenting and communicating those hazards to create a permanent knowledge and understanding within the organization operating that process.A culture of Technical Discipline will reveal reaction hazards that might otherwise remain unknown until being unveiled in a dramatic and unexpected fashion. Until you fully identify and characterize the hazards of the materials you handle in your processes…what you don't know can hurt you.  相似文献   
40.
Arctic-breeding shorebirds collected in western Washington state during winter and spring, and a comparative sample collected in coastal California during the winter were analyzed for organochlorine contaminants to determine the potential impact of these residues on populations of peregrine falcons (Falco peregrinus) and merlins (F. columbarius) which prey upon shorebirds in western Washington. Dunlins (Calidris alpina), an important winter prey for falcons in western Washington, were collected between 1975 and 1981. During winter 1980–81, dunlins carried low organochlorine residues; DDE levels ranged from 0.01 to 1.2 ppm, and PCB levels ranged from 0.02 to 0.82 ppm (wet weight). Levels of other organochlorine contaminants (HCB, Chlordane compounds, Dieldrin, and Heptachlor Epoxide), analyzed in a subsample of dunlins, were consistently lower than DDE and PCB levels, and ranged from 0.001 to 0.22 ppm (wet weight). Dunlins in western Washington did not significantly increase their DDE or PCB burdens over the 1980–81 winter. A decline in DDE residues between 1978 and 1981 was noted, and declines in PCB residues from both 1975 and 1978 to 1980–81 were noted. Residues in other wintering shorebirds from western Washington were similar. Wintering sanderlings (Calidris alba) from California, revealed much higher DDE contamination than in Washington (up to 32 ppm, wet weight). Spring migrant shorebirds in western Washington contained both low and very high DDE residues (up to 417 ppm, wet weight). There is evidence suggesting these high DDE concentrations are accumulated along the Pacific coast of North America.  相似文献   
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