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31.
Webb P 《Disasters》1993,17(1):33-47
In this article I examine the impact of drought on farm households in Ethiopia and their response to crisis conditions. I ask whether every household in a community is equally affected by drought and what households do to mitigate the effects of drought and associated food insecurity. Information on production, income and food consumption is disaggregated by agroecological zone (highland and lowland), and by socioeconomic strata (relatively wealthy versus poor). Such detailed analysis permits an improved understanding of why the poor are much more vulnerable than the wealthy to drought and associated famines and why they need to be more effectively targeted by relief and development interventions. In a world of limited public resources for crisis intervention, such understanding is crucial to the design of improved policies and projects for reaching people most at risk.  相似文献   
32.
An account is given of a pregnancy in an obligatory carrier of the fragile-X syndrome, in whom examination of chorionic villus cells and fetal blood cells showed the presence of a male fetus who lacked the fragile-X chromosome. However, at 3 months of age he had 14 per cent of fragile-X cells in his blood. Reasons are suggested for this error in diagnosis. The empirical risk for an error of this sort is 3 per cent.  相似文献   
33.
ABSTRACT: The major objective is to report the way the Delphi methodology was employed in an environmental study aimed at identifying and ranking goals and social impacts of Cooper Dam and Reservoir Project located in the East Texas area. The Delphi procedures were modified to accommodate the nature of social field under study. Data were collected through personal interviews from twenty-seven respondents representing the government agency responsible for planning the Project and three communities geographically contiguous to the project. The respondents were provided an initial list of the Project's goals and social impacts and were asked to rank them in terms of degree of importance and to add to the list other goals and impacts that they would consider necessary. Respondents were interviewed in two successive rounds. Data show that on the whole the Delphi procedures were helpful in action analysis of the Project by identifying and ranking its goals and social impacts in terms of selected criteria.  相似文献   
34.
Studies of the influence of parasites on host fitness generally conclude that parasites have a strong negative effect on their hosts. In this study, we have investigated experimentally the role of Polymorphus minutus, an acanthocephalan parasite, on the salinity tolerance of the freshwater amphipod Gammarus roeseli, one of its intermediate hosts. Unexpectedly, P. minutus-infected gammarids were more tolerant to salinity stress than uninfected ones. The mean lethal salt concentrations for 50% mortality of hosts tested were 17.3 (infected) and 9.7 g/L (uninfected). The parasitic load (one or two parasites per host) did not affect the result. The size of hosts had no significant influence on the salinity tolerance of either infected or uninfected gammarids. The mobility of all types of gammarid decreased when the salinity exceeded 9.0 g/L, but there was no significant difference between infected and uninfected gammarids. We discuss the higher salinity tolerance of infected amphipods in relation to O2 consumption and osmoregulation. Finally, we demonstrate that the salinity tolerance is enhanced in the parasitized amphipod but without a significant change in behavior or an osmoregulatory adjustment.  相似文献   
35.
Foliar absorption of resuspended 90Sr, root uptake and contamination adhering to leaf surfaces (i.e. soil loading) were compared at two Chernobyl-contaminated sites, Chistogalovka and Polesskoye. Although foliar absorption of resuspended 90Sr was quantifiable, its contribution amounted to less than 10% of the plants' total, above-ground contamination. Root uptake was 200 times greater than foliar absorption at the near-field site of Chistogalovka and eight times greater at Polesskoye, where the fallout consisted of the more soluble condensation-type, rather than fuel particles. Strontium's bioavailability exceeded that of 137Cs (analyzed in the same plants) by orders of magnitude when compared using concentration ratios. Simplistic, cumulative effective dose calculations for humans ingesting 90Sr- and 137Cs-contaminated plants revealed that the dose at Chistogalovka was greater from 90Sr (185 mSv vs. 3 mSv from 137Cs), while at Polesskoye the dose from 137Cs (66 mSv) was 30 times greater than from 90Sr (2 mSv).  相似文献   
36.
US government actions undertaken in Antarctica are subject to the requirements of both the Protocol and the US National Environmental Policy Act (NEPA). There are differences in the scope and intent of the Protocol and NEPA; however, both require environmental impact assessment (EIA) as part of the planning process for proposed actions that have the potential for environmental impacts. In this paper we describe the two instruments and highlight key similarities and differences with particular attention to EIA. Through this comparison of the EIA requirements of NEPA and the Protocol, we show how the requirements of each can be used in concert to provide enhanced environmental protection for the antarctic environment. NEPA applies only to actions of the US government; therefore, because NEPA includes certain desirable attributes that have been refined and clarified through numerous court cases, and because the Protocol is just entering implementation internationally, some recommendations are made for strengthening the procedural requirements of the Protocol for activities undertaken by all Parties in Antarctica. The Protocol gives clear and strong guidance for protection of specific, valued antarctic environmental resources including intrinsic wilderness and aesthetic values, and the value of Antarctica as an area for scientific research. That guidance requires a higher standard of environmental protection for Antarctica than is required in other parts of the world. This paper shows that taken together NEPA and the Protocol call for closer examination of proposed actions and a more rigorous consideration of environmental impacts than either would alone. Three areas are identified where the EIA provisions of the Protocol could be strengthened to improve its effectiveness. First, the thresholds defined by the Protocol need to be clarified. Specifically, the meanings of the terms “minor” and “transitory” are not clear in the context of the Protocol. The use of “or” in the phrase “minor or transitory” further confuses the meaning. Second, cumulative impact assessment is called for by the Protocol but is not defined. A clear definition could reduce the chance that cumulative impacts would be given inadequate consideration. Finally, the public has limited opportunities to comment on or influence the preparation of initial or comprehensive environmental evaluations. Experience has shown that public input to environmental documents has a considerable influence on agency decision making and the quality of EIA that agencies perform.  相似文献   
37.
Six N-flow models, used to calculate national ammonia (NH3) emissions from agriculture in different European countries, were compared using standard data sets. Scenarios for litter-based systems were run separately for beef cattle and for broilers, with three different levels of model standardisation: (a) standardized inputs to all models (FF scenario); (b) standard N excretion, but national values for emission factors (EFs) (FN scenario); (c) national values for N excretion and EFs (NN scenario). Results of the FF scenario for beef cattle produced very similar estimates of total losses of total ammoniacal-N (TAN) (±6% of the mean total), but large differences in NH3 emissions (±24% of the mean). These differences arose from the different approaches to TAN immobilization in litter, other N losses and mineralization in the models. As a result of those differences estimates of TAN available at spreading differed by a factor of almost 3. Results of the FF scenario for broilers produced a range of estimates of total changes in TAN (±9% of the mean total), and larger differences in the estimate of NH3 emissions (±17% of the mean). The different approaches among the models to TAN immobilization, other N losses and mineralization, produced estimates of TAN available at spreading which differed by a factor of almost 1.7. The differences in estimates of NH3 emissions decreased as estimates of immobilization and other N losses increased. Since immobilization and denitrification depend also on the C:N ratio in manure, there would be advantages to include C flows in mass-flow models. This would also provide an integrated model for the estimation of emissions of methane, non-methane VOCs and carbon dioxide. Estimation of these would also enable an estimate of mass loss, calculation of the N and TAN concentrations in litter-based manures and further validation of model outputs.  相似文献   
38.
Terms such as 'vulnerability' and 'insecurity' are used widely in the general nutrition literature as well as in work on humanitarian response. Yet these words are used rather loosely. This paper argues that more clarity in their usage would benefit those seeking a bridge between development and humanitarian problems. Since vulnerability is not fully coincident with malnutrition, poverty or other conventional indices of human deprivation, public action must be based on a better understanding of the nature of crises and human uncertainty beyond physiological and nutritional outcomes. More attention is needed to be paid to the context-specific nature of risks, the capacity of households to manage such risks and the potential for public action to bolster indigenous capacity through targeted development investments, not just relief.  相似文献   
39.
40.
A Conference on Air Quality Management in the Electric Power Industry was held at The University of Texas at Austin in Austin, TX, on January 28-30, 1976. The opening session of the Conference was devoted to legal and regulatory issues in air pollution control related to the electric power industry. The purpose of this session was to present the viewpoints of those Federal and state regulatory agencies most directly involved in air pollution control for the electric power industry. Emphasis was placed on those issues relating to the increasing need for coal and oil combustion to meet the Nation’s electrical energy requirements, concentrating on the five southwestern states of Arkansas, Louisiana, New Mexico, Oklahoma, and Texas in Federal Region VI.  相似文献   
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