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1.
We examined data on sex-specific differences in neonatal weight, litter size and adult female body weight in 32 populations of polygynous ungulates of 18 different species to test for the existence of a trade-off between sex-biased maternal care and the total amount of maternal expenditure. This corresponds to an extension of the hypothesis of Byers and Moodie (1990) that sex-biased maternal care is limited by a high level of maternal expenditure. We did not find any relationship between sex-biased care and two measures of total maternal expenditure. We highlighted high intraspecific variability in sex-biased care and very low intraspecific variability in total maternal expenditure. Even when this between-population variability in sex-biased care was accounted for, no relationship between sex-biased maternal care and maternal expenditure was detected. Apart from difficulties in finding suitable measures for both variables, two other reasons may account for the lack of a relationship between sex-biased maternal care and total maternal expenditure. Firstly, male offspring seem to be more affected than female offspring by harsh environmental conditions. This may lead to the variation observed in the extent of sex-specific differences in birth weight within a single species. If we assume that for a given maternal expenditure reproductive costs incurred by mothers are highest during harsh conditions, this could indicate the existence of a trade-off between sex-biased maternal care and maternal expenditure at the intra-specific level, thereby supporting the Byers and Moodie hypothesis. Secondly, polygyny is only a poor predictor of sex-biased care and factors such as compensatory growth or extended periods of growth may be expected to modify predictions for different species. Thus, environmental conditions and relative effects of maternal care on male and female lifetime reproductive success are better predictors of sex-biased care than total maternal expenditure.Communicated by P.M. Kappeler  相似文献   
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The Bio-response Operational Testing and Evaluation (BOTE) Project was a cross-government effort designed to operationally test and evaluate a response to a biological incident (release of Bacillus anthracis [Ba] spores, the causative agent for anthrax) from initial public health and law enforcement response through environmental remediation. The BOTE Project was designed to address site remediation after the release of a Ba simulant, Bacillus atrophaeus spp. globigii (Bg), within a facility, drawing upon recent advances in the biological sampling and decontamination areas. A key component of response to a biological contamination incident is the proper management of wastes and residues, which is woven throughout all response activities. Waste is generated throughout the response and includes items like sampling media packaging materials, discarded personal protective equipment, items removed from the facility either prior to or following decontamination, aqueous waste streams, and materials generated through the application of decontamination technologies. The amount of residual contaminating agent will impact the available disposal pathways and waste management costs. Waste management is an integral part of the decontamination process and should be included through “Pre-Incident” response planning. Overall, the pH-adjusted bleach decontamination process generated the most waste from the decontamination efforts, and fumigation with chlorine dioxide generated the least waste. A majority of the solid waste generated during pH-adjusted bleach decontamination was the nonporous surfaces that were removed, bagged, decontaminated ex situ, and treated as waste. The waste during the two fumigation rounds of the BOTE Project was associated mainly with sampling activities. Waste management activities may represent a significant contribution to the overall cost of the response/recovery operation. This paper addresses the waste management activities for the BOTE field test.Implications: Management of waste is a critical element of activities dealing with remediation of buildings and outdoor areas following a biological contamination incident. Waste management must be integrated into the overall remediation process, along with sampling, decontamination, resource management, and other important response elements, rather than being a stand-alone activity. The results presented in this paper will provide decision makers and emergency planners at the federal/state/tribal/local level information that can be used to integrate waste management into an overall systems approach to planning and response activities.  相似文献   
3.
This study evaluated the microbiocidal efficacy of a cleaning and disinfection (C&D) treatment using stainless-steel coupons applied to three common types of animal mortality transport vehicles when exposed to agricultural conditions. Metal test coupons, inoculated with bacteriophage MS2, were affixed to the undercarriage of three types of animal mortality transport vehicles at various locations. Coupons were grimed by maneuvering the test vehicles down a series of wet dirt roads. Coupons were attached and extracted at various points to evaluate C&D performance with and without grime. C&D efficacy using a water-supplied pressure washing system and a dilute sodium hypochlorite (NaOCl) solution was determined by comparing the difference in recovered viable virus between positive control coupons and test coupons. The results demonstrated a relatively high surface decontamination efficacy, with all but one location showing >5 log reduction of MS2. Coupons located on the roll-off truck's inside-back bumper contained the highest level of grime and resulted in a 4 log reduction of MS2. There was no significant difference in C&D efficacy across vehicle types, but locations impacted by grime and lack of accessibility achieved lower efficacies on average. These findings suggest that common C&D protocols, when applied to farm mortality transport vehicles, are effective. Hard-to-access locations containing high levels of grime may be candidates for additional targeted treatment.  相似文献   
4.
ABSTRACT

Tire-derived fuel (TDF) was tested in a small-scale (44 kW or 150,000 Btu/hr) combustor to determine its feasibility as a fuel for use in reburning for control of nitrogen oxide (NO). TDF was gravity-fed into upward flowing combustion gases from a primary natural gas flame doped with ammonia to simulate a high NO combustion process. Emissions of NO, oxygen, carbon dioxide, carbon monoxide, and particulate matter were measured. The tests varied the nominal primary NO level from 600 to 1,200 ppm and the primary stoichiometry from 1.1 to 1.2, and used both natural gas and TDF as reburn fuels. The reburn injection rate was varied to achieve 8–20% of the total heat input from the reburn fuel. NO emissions reductions ranged between 20 and 63% when using TDF, depending upon the rate of TDF injection, primary NO, and primary stoichiometry. NO emission reductions when using natural gas as the reburn fuel were consistently higher than those when using TDF. While additional work remains to optimize the process and evaluate costs, TDF has been shown to have the potential to be a technically viable reburning fuel.  相似文献   
5.
This paper examines the impact of training programs on the ability of trainee watch officers to make decisions in collision avoidance situations.It draws on previous studies which have shown that experts are able to manage complex situations in an acceptable way. However, observations of students on simulators have revealed that many of them are unable to manage such situations or even to recall their main features. It is therefore necessary to identify new training tools that will give trainees the capacity to assess a situation quickly and accurately, and to perform satisfactory actions. These would be in addition to formal regulations.Exercises were designed to evaluate the impact of such tools on the decision-making process of trainees. The impact of the type of navigation experienced by trainees during their on-the-job training was also evaluated.Results showed that decision-making exercises did tend to improve the trainees’ capacity to analyse a complex situation; however, they did not have a clear impact on the manoeuvre performed. On the contrary, there was an obvious difference between the trainees who experienced complex avoidance situations during their on-the-job training period and those who did not.At a time where ship-owners are looking to reduce the length of the “on-the-job” training period, these results point to its vital importance.  相似文献   
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This paper examines the viability of the prefabricated detached dwelling, in France, as a home and shelter. It also considers its symbolic nature, and its role both as an investment and a form of inheritance. It is based on an exploratory survey in which 20 householders were interviewed in depth and their comments analysed by means of a specific method of content analysis. Consumer choices are investigated by establishing what prefabrication offers in relation to traditional housing, in terms of the construction process, acquisition procedures, architectural style and cost. Then the author examines ‘inhabiting’ and the feasibility of these houses as an inheritable property with reference to the cultural models of the purpose-built house.It was found that prefabricated housing is a solution suited to all professionally mobile people and to the retired. This adaptation makes home ownership compatible with residential mobility, quite the reverse of what is popularly believed.  相似文献   
10.
In the context of biosolids utilisation in forestry, effects of sludge application on mushroom metal concentration were studied in six sites of maritime pine forests in the South-West of France. Municipal sludge were applied at a rate of 6 T dry matter per hectare. Edible mushrooms were collected two years after sludge application. As, Cd, Cu, Hg, Pb, Se and Zn concentrations were determined. Results showed a high variability for trace element concentrations in mushrooms collected from control areas. No significant correlation was found between soil parameters (pH and trace elements concentrations) and mushroom trace element concentrations. Even if the concentration of trace metals increased in the soils, sludge application did not affect As, Cu, Se and Zn concentrations in carpophores but slightly increased Cd, Pb and Hg concentrations on some sites. This effect is dependent on sludge type and sites.  相似文献   
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