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11.
ABSTRACT

In this paper, assumptions regarding future land use as a key uncertainty is considered and its impact on risk analysis for contaminated sites is assessed. Risks are assessed for two land use scenarios (current-use industrial and future-use residential) using probabilistic models that incorporate uncertainty and variability in the exposure parameters. Residual risks are calculated for both industrial and residential cleanup standards. A Superfund site in northern California is considered.

In general, for the unremediated case, the future-use residential scenarios produce larger risks (1 to 3 orders of magnitude) than current- (continued) use industrial scenarios. For the Superfund site studied, the residual risks calculated for the remedy selected was not sufficiently protective of future-use residents in that it did not meet .S. Environmental Protection Agency (EPA) risk goals, but was protective of current-use workers, even though the cleanup criteria were based on residential use. Alternative risk management practices, such as deed restrictions, can be used in such cases.  相似文献   
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Abstract

The São Paulo Metropolitan area (SPMA) is characterized as having one of the worst air pollution problems in Brazil,with frequent violations of air quality standards for particulate matter. This paper presents the results of a eceptor model source apportionment study carried out to develop a quantitative database on which a control strategy could be developed. The study was conducted in four sites with distinct land uses. Fine, coarse (CP), and total suspended particles (TSP) samples were collected on Teflon and glass filters and analyzed by x-ray fluorescence XRF), ion chromatography, and thermal evolution. The sources were characterized by similar methodology. Chemical mass balance (CMB) receptor modeling indicated that carbonaceous material plays an important role in the aerosol composition; that the three major source categories contributing to the fine particles are vehicles, secondary carbon, and sulfates; and that the main contributors to CP and TSP are road dust and vehicles. All sampling sites presented the same general pattern in terms of source contribution, although this contribution varied from site to site.  相似文献   
15.
When deep-water samples from the Mediterranean Sea were passed through glass-fibre filters (Whatman GF/F), the adenosine nucleotide concentration of the particulate material was exceptionally low. The concentration was higher when the particulate material was concentrated on SM cellulose-membrane filters with porosities of less than 1 μm. There would seem to be two reasons for this: (1) inhibition of the bioluminescent reaction; (2) an apparently lower retention of ATP by the glass-fibre filters. In order to compare results obtained with the two different types of filters, a correction factor of two can be used if measurements are made with an internal standard. This constant factor can only be applied to samples from depths greater than 300 m.  相似文献   
16.
While there is ample – though partially contradictory – evidence regarding the effects climate change will have on various regions of the world, there is only very limited work dedicated to the analysis of different governance structures, and how these structures are likely to influence the resilience of alpine tourism systems in the face of climate change. We present an analytical framework based on network theory, and apply this to the Swiss case study destination of Engelberg, in order to deduct a number of insights for the future assessment of resilience based on the cooperation of local actors. The main aim of the paper is to come up with comparable resilience metrics based on social network analysis in order to assess the structural strengths and weaknesses of a geographically delimited tourism system in the face of climate change. Together with the action potential of the individual actors these structural properties influence the adaptive capacity of both individual actors, and the tourism system as a whole. In line with comparable studies, we identify structural strengths and weaknesses around the core-periphery distribution (centrality), subgroups (modularity) and information flows (path length). We find that the Engelberg network follows an almost ideal-typical scale-free structure and the overall cooperation rate (density) is comparable to other tourism networks. The main weaknesses of the network with regard to climate change resilience are the lacking integration of public sector actors and the relatively high number of actors in the periphery of the network.  相似文献   
17.
Recent studies have shown that there are many effects of climate change on aeroallergens, and thus on allergic diseases in humans. In the Mediterranean region, despite the importance of the olive tree for production, there is high allergenicity of olive pollen and related risks to human health. Aerobiological sampling techniques can be used to analyse the pollinosis phenomenon through determination of mean daily pollen concentrations per cubic metre of air. The present study was carried out from 1999 to 2008 in 16 olive-growing areas in Italy, to update the information on the pollinosis characteristics of Olea europaea in the study areas. The analysis of the average flowering season over the study period highlights a temporal scaling of pollen in the atmosphere that depends on the different climatic characteristics. This is mainly dependent on temperature, and in part, determined by latitude. Generally, the levels of O. europaea pollen in the atmosphere are higher from mid-April to the end of June, with the period of greatest risk to human health due to this olive pollen in this area currently limited primarily to the last 10 days of May. However, the pollen season can move, depending on the climate scenario considered, and data here can be used to determine potential time shifts in pollinosis that might cause more precocious asthma and allergy problems. The allergy season for this type of pollen might be significantly precocious in future decades (20–30 days earlier in the year), which will impact on the severity and duration of allergies attributable to olive tree pollen.  相似文献   
18.
Egg production, fecal pellet production and hatching success are reported for Acartia clausi females sampled during three cruises in February 1997, 1998 and June 1997 at 20-24 stations along 4 transects in the North Adriatic Sea. Dramatically low hatching rates were recorded during both diatom bloom events in February as opposed to much higher rates during post-bloom conditions in June, even though A. clausi productivity during the bloom was apparently high. These results are discussed in the light of recent findings on the negative impact of diatoms on copepod reproductive potential.  相似文献   
19.
In men, the length ratio of the second to fourth finger (2D:4D) is smaller, while the length of the fourth finger relative to body height (4D:H) is larger than in women. Inter- and intrasexual variations in 2D:4D and 4D:H may depend on variation in fetal androgen and oestrogen environment. As maternal physiology varies with parity and is differentially affected by gestation of either sex, offspring 2D:4D and 4D:H may change according to sex and number of older siblings and may predict subsequent maternal performance. We analysed 2D:4D and 4D:H in Caucasian university students. 2D:4D was smaller and 4D:H was larger in males than in females, but no sexual dimorphism existed in 2D:H. In males, length ratios did not vary with birth order. 2D:4D became more masculine with increasing proportion of males among older siblings, and 2D:4D and 4D:H became more feminine as the number of older sisters increased. In females, length ratios did not vary with the number of older sisters or brothers. 2D:4D was also not related to birth order, but 4D:H became more masculine with birth order. In females, residual maternal fecundity (number of maternal offspring after the participant) decreased as 4D:H became more masculine. These findings are partly consistent with those from previous studies and suggest that maternal fecundity co-varies with length ratios and thus possibly fetal hormone environment of older offspring. 2D:4D and 4D:H may therefore represent powerful tools to investigate the relationships between fetal environment, offspring phenotype and maternal life history at mechanistic and evolutionary levels.  相似文献   
20.
Sediment cores, obtained in 2004–2005 and in 2008 from seven coastal lagoons of Central Vietnam (Lang Co, Nuoc Man, Nuoc Ngot, Thi Nai, O Loan, Thuy Trieu and Dam Nai), were analysed to assess changes in 210Pb, porosity, grain size, and depth distributions of selected major and trace elements (Al, As, Ni, and Zn). The aim was to trace sedimentary processes in areas periodically subject to extreme events. The occurrence of lateral sedimentary inhomogeneities has been hypothesised to explain the differences observed at depth for some tracer profiles, whereas topmost levels present evidence that accounts for the loss of a sediment layer (from 2.0 to 7.5 cm thick) between the two samplings. These losses might be attributed to major typhoons that impacted the coasts of Central Vietnam during the study period.  相似文献   
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