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461.
In this paper I critique two popular, non-scientific attitudes toward genetically engineered foods. In doing so, I will be employing the concepts of ambiguity, purity/impurity, control/resistance, and unity/diversity as developed by Latina feminist metaphysicians. I begin by casting a critical eye toward a specific anti-biotech account of transgenic food crops, an account that I will argue relies on an anti-feminist metaphysics. I then cast that same critical eye toward a specific pro-biotech account, arguing that it also relies on such an anti-feminist metaphysics. I will argue further that this metaphysics yields a less accurate account of genetics. I end by arguing that if we adopt a Latina feminist metaphysics we can more accurately understand plants, genetics, and genetic engineering.  相似文献   
462.
Using the approach established by EPA's Environmental Monitoring and Assessment Program (EMAP), a shoreline monitoring survey was conducted in August and September 1999, encompassing the Florida Panhandle from Perdido Key, Florida to Port St. Joe, Florida. The objective of this survey was to demonstrate the use of a probabilistic survey for monitoring and estimating the condition of swimmable beach areas. Thirty stations were sampled using a probabilistic sampling design. Hydrographic data were collected in addition to samples for water chemistry. Bacterial indicators, enterococci and fecal coliforms, were enumerated from the water according to the EPA Beaches Environmental Assessment Closure and Health (BEACH) Program and Florida state guidelines. Additional criteria for site condition included the presence or absence of primary and secondary dunes, anthropogenic debris and vegetation. Based on EMAP evaluation guidelines and Florida state criteria, a baseline assessment of the condition of the Gulf of Mexico beach resources surveyed is presented.  相似文献   
463.
The objective of this study was to establish whether EU and UN-ECE/ICP-Forests monitoring data (i) provide the variables necessary to apply the flux-based modeling methods and (ii) meet the quality criteria necessary to apply the flux-based critical level concept. Application of this model has been possible using environmental data collected from the EU and UN-ECE/ICP-Forests monitoring network in Switzerland and Italy for 2000-2002. The test for data completeness and plausibility resulted in 6 out of a possible total of 20 Fagus sylvatica L. plots being identified as suitable from Switzerland, Italy, Spain, and France. The results show that the collected data allow the identification of different spatial and temporal areas and periods as having higher risk to ozone than those identified using the AOT40 approach. However, it was also apparent that the quality and completeness of the available data may severely limit a complete risk assessment across Europe.  相似文献   
464.
Thermal degradation of PCDD/F, PCB and HCB in municipal solid waste ash   总被引:1,自引:0,他引:1  
Lundin L  Marklund S 《Chemosphere》2007,67(3):474-481
A thermal degradation procedure for reducing the concentrations of mono- to octa-chlorinated PCDD/Fs, PCBs and hexa-chlorobenzenes (HCB) in filter ash from incinerated municipal solid waste (MSW) is described. Thermal treatment of filter ash samples at 500 degrees C for 60 min in a closed system providing low oxygen conditions resulted in 97% and 99% reductions in the total and I-TEQ concentrations of PCDD/Fs, to 6.8 microg kg(-1) ash and <0.05 microg I-TEQ kg(-1) ash, respectively. Increasing the thermal treatment time to 480 min, at the same temperature, yielded 99% reductions in both total and I-TEQ concentrations of the mono- to octa-chlorinated PCDD/Fs. Similar effects were observed for HCB and PCBs. The data from this study indicate that PCDD/Fs and other toxic organic compounds in ash from incinerated MSW, can be effectively degraded by this procedure, which combines relatively low-temperatures, short treatment times, and low oxygen conditions.  相似文献   
465.
Understanding the history of how humans have interacted with the rest of nature can help clarify the options for managing our increasingly interconnected global system. Simple, deterministic relationships between environmental stress and social change are inadequate. Extreme drought, for instance, triggered both social collapse and ingenious management of water through irrigation. Human responses to change, in turn, feed into climate and ecological systems, producing a complex web of multidirectional connections in time and space. Integrated records of the co-evolving human-environment system over millennia are needed to provide a basis for a deeper understanding of the present and for forecasting the future. This requires the major task of assembling and integrating regional and global historical, archaeological, and paleoenvironmental records. Humans cannot predict the future. But, if we can adequately understand the past, we can use that understanding to influence our decisions and to create a better, more sustainable and desirable future.  相似文献   
466.
An observational field study was conducted to assess the feasibility of a community duplicate diet collection method; a dietary monitoring tool that is population-based. The purpose was to establish an alternative procedure to duplicate diet sampling that would be more efficient for a large, defined population, e.g., in the National Children's Study (NCS). Questionnaire data and food samples were collected in a residence so as not to lose the important component of storage, preparation, and handling in a contaminated microenvironment. The participants included nine Hispanic women of child bearing age living in Apopka, FL, USA. Foods highly consumed by Hispanic women were identified based on national food frequency questionnaires and prioritized by permethrin residue concentrations as measured for the Pesticide Data Program. Participants filled out questionnaires to determine if highly consumed foods were commonly eaten by them and to assess the collection protocol for the food samples. Measureable levels of permethrin were found in 54% of the samples. Questionnaire responses indicated that the collection of the community duplicate diet was feasible for a defined population.  相似文献   
467.
Methods for household waste composition studies   总被引:1,自引:0,他引:1  
The question is how to conduct household waste composition studies. The review is divided into three parts: overview of known methods, sampling theory, and the waste components. Twenty methods are listed and commented on. There is no adopted, working international standard. In accordance with Pierre Gy's Theory of Sampling, the seven types of sampling errors, when collecting and splitting solid samples, are described and commented on in relation to sampling of household solid waste. It is concluded that the most crucial choices in household waste composition studies are: to divide the investigation into relevant number and types of strata; to decide the required sample size and number of samples; to choose the sampling location, i.e., sampling at household level or sampling from loads of waste collection vehicles; and to choose the type and number of waste component categories to be investigated. Various classifications of household waste components used in composition studies are listed and discussed. Difficulties and weaknesses of the reviewed methods are discussed and concluded in suggested questions for further research.  相似文献   
468.
This article presents a methodological framework for strategic environmental assessment (SEA) application. The overall objective is to demonstrate SEA as a systematic and structured policy, plan, and program (PPP) decision support tool. In order to accomplish this objective, a stakeholder-based SEA application to greenhouse gas (GHG) mitigation policy options in Canadian agriculture is presented. Using a mail-out impact assessment exercise, agricultural producers and nonproducers from across the Canadian prairie region were asked to evaluate five competing GHG mitigation options against 13 valued environmental components (VECs). Data were analyzed using multi-criteria and exploratory analytical techniques. The results suggest considerable variation in perceived impacts and GHG mitigation policy preferences, suggesting that a blanket policy approach to GHG mitigation will create gainers and losers based on soil type and associate cropping and on-farm management practices. It is possible to identify a series of regional greenhouse gas mitigation programs that are robust, socially meaningful, and operationally relevant to both agricultural producers and policy decision makers. The assessment demonstrates the ability of SEA to address, in an operational sense, environmental problems that are characterized by conflicting interests and competing objectives and alternatives. A structured and systematic SEA methodology provides the necessary decision support framework for the consideration of impacts, and allows for PPPs to be assessed based on a much broader set of properties, objectives, criteria, and constraints whereas maintaining rigor and accountability in the assessment process.  相似文献   
469.
Before wood ash can be used as a soil fertilizer, concentrations of environmentally hazardous compounds must be investigated. In this study, total and leachable concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) were determined in four ash samples and one green liquor sludge. The ash sample with the highest carbon content also contained high levels of PAHs; three of the ash samples had total concentrations exceeding the limit permitted by the Swedish Forest Agency for recycling to forest soils. The leachable concentrations were higher for the non-stabilized samples; this was probably due to colloid-facilitated transport of the contaminants in these samples. However, the leachable concentrations were overall relatively low in all the samples studied. The amounts of PAHs introduced to forest soils by additions of stabilized, recyclable ash products will be determined primarily by the rate of weathering of the ash particles and the total concentration of contaminants.  相似文献   
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