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621.
Residential concentrations of formaldehyde have been associated with poor respiratory health in children, where formaldehyde has been measured using stationary monitors inside homes. Although children spend most of their time indoors at home, there are few studies of children’s personal exposure to formaldehyde. The aim of this study was to investigate the relationship between personal exposure formaldehyde concentrations, microenvironmental concentrations and time weighted exposure estimates in children.Forty-one primary school children (aged between 9 and 12 years) wore a personal passive sampler over two 24 h periods in two seasons and completed 24 h daily activity diaries and a questionnaire about lifestyle and behaviour. Samplers were co located indoors at home, outdoors at centralised locations and indoors at school for the corresponding period.Personal exposure formaldehyde concentrations in this group of children were generally low with a geometric mean concentration of 9.1 ppb (range <detection limit to 27.3 ppb). There were strong correlations between personal exposure concentrations and both domestic indoor (rs = .779, p < 0.001) and time weighted estimated (rs = .802, p < 0.001) concentrations. The time weighted model did not improve the estimate of personal exposure compared with stationary indoor concentrations. Indoor air concentration measured with a single stationary monitor was a suitable surrogate for personal exposure.  相似文献   
622.
The impact of the number of displayed credentials (0, 2, 4, or 9) and the presence or absence of family photographs on participants' judgments of a therapist's qualities was assessed. In a between-participants design, 227 participants made these judgments after viewing a projected digital image of a therapist's office. The judgments of the characteristics yielded three factors, Qualifications, Friendliness, and Energy. Analyses indicated that in general, the greater the number of credentials, the more positive the judgment of the therapist's Qualifications and Energy. The presence of family pictures had no significant impact on judgments. Results are discussed in terms of recommendations for the counseling environment.  相似文献   
623.
Polycyclic aromatic hydrocarbons (PAHs) are organic pollutants derived from pyrolysis and pyrosynthesis processes. Industrial activity, motor vehicle emission, and domestic combustion are the main sources of PAHs in the urban atmosphere. In this work, samples collected during the day and night in the urban area of Sarajevo are analyzed separately for gaseous and particle-bound PAHs; the possible origin of PAHs at the receptor site was suggested using different methods applied to the solid phase and to the total PAHs (gaseous + particulate phase). Finally, the risk level in Sarajevo associated to the carcinogenic character of the studied PAHs has been assessed. The result of this study suggests that (a) the total PAH concentrations were higher than those reported in other European cities; (b) the PAH daytime concentrations are higher than nocturnal concentrations: the sum of the PAH day/night ratios is 1.52 (gas) and 1.45 (particle phase); (c) stationary combustion and traffic were suggested to be the main sources of PAHs; (d) the average particle-bound benzo(a)pyrene (BaP) concentration (5.4 ng/m3) is higher than EU target annual value (1 ng/m3); and (e) PAH cancer risk exceeds the carcinogenic benchmark level recommended by the EPA mainly due to BaP during both the day and night periods.  相似文献   
624.
Background, Aim and Scope Agricultural industrial wastes can frequently be used as raw materials in the production of bio-fuels. Olive-oil milling wastewater is considered as one of the most polluting agro-industrial residues, but fortunately due to its high content of organic matter, it has the potential to be a valuable starting material to obtain bio-ethanol via fermentation with Saccharomyces cerevisiae. The fermentation of olive-oil milling wastewater has been demonstrated with good yield of ethanol (8-12%v/v) once the level of reducing sugars is appropriate and the phenolic fraction, which inhibits the yeast, is removed. Materials and Methods: - Results: - Discussion: - Conclusions: - Recommendations and Perspectives: -  相似文献   
625.
The concentrations of gas-phase PCBs were measured from March 2002 to June 2003 at two sites of the Venice Lagoon and at one site of the Euganei hills. The aims of this study were to evaluate the various gas-phase PCB sources, the spatial and temporal variability of PCB concentrations in the gas-phase that enter the Venice Lagoon atmosphere and the influence of the air temperature on PCB trends. The highest annual average concentration of summation PCBs was observed at the station directly influenced by "urban" sources with values about 3 and 1.5 times higher compared to the concentrations found at the stations where "marine" sources and "not subjected to direct local sources" were respectively sampled from. The temporal trends of summation PCBs concentrations were similar at the three sampling stations corresponding to seasonal temperature changes. Greater concentrations occurred in the summer and first autumn months while the lower ones occurred in late autumn and winter. The temperature dependences were investigated using plots of the natural logarithm of the summation PCBs concentrations vs. reciprocal mean temperatures.  相似文献   
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Recently, environmentally conscious design and extended producer responsibility have become key aspects for companies that need to develop products that are sustainable along their whole life cycle. Design for End of Life (EoL) is a strategy that aims to reduce landfill waste through the implementation of closed-loop product life cycles. It is important to consider disassembly and EoL scenario management as early as the design phase. For these reasons, this paper presents an approach to help designers in the evaluation and subsequent improvement in product EoL performance. The method is based on four innovative EoL indices that compare different EoL scenarios for each product component. In this way, the designer can modify the product structure or the liaisons to maximise the reuse and remanufacture of components as well as material recycling. The presented case studies confirm the validity of the approach in helping designers during the redesign phase of goods and products to reduce the quantity of materials and industrial wastes sent to landfill.  相似文献   
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630.
Recent concerns about potential climate-change effects on coastal systems require the application of vulnerability assessment tools in order to define suitable adaptation strategies and improve coastal zone management effectiveness. In fact, while various research efforts were devoted to evaluate coastal vulnerability to climate change on a national to global level, fewer applications were carried out so far to develop more comprehensive and site-specific vulnerability assessments suitable to plan possible adaptation measures at the regional scale. In this respect, specific indicators are needed to address climate-change-related issues for coastal zones and to identify vulnerable areas at the regional level. Two sets of coastal vulnerability indicators were selected, one for regional and one for global studies, respectively, concerning the same features of coastal systems, including topography and slope, geomorphological characteristics, presence and distribution of wetlands and vegetation cover, density of coastal population and number of coastal inhabitants. The proposed set of indicators for the regional scale was chosen taking into account the availability of environmental and territorial data for the whole coastal area of the Veneto region and was based on site-specific datasets characterized by a spatial resolution appropriate for a regional analysis. Moreover, a GIS-based segmentation procedure was applied to divide the coastline into linear segments, homogeneous in terms of vulnerability to climate change and sea-level rise at the regional scale. This approach allowed to divide the Veneto shoreline into 140 segments with an average length of about 1 km, while the global scale approach identified four coastal segments with an average length of about 66 km. The performed comparison indicated how the more detailed approach adopted at the regional scale is essential to understand and manage the complexities of the specific study area. In fact, the 25-m DEM employed at the regional scale provided a more accurate differentiation of the coastal area's elevation and thus of coastal susceptibility to the inundation risks, compared to the 1-km DEM used at the global level. Moreover, at the regional level the use of a 1:20,000 geomorphological map allowed to differentiate the unique landform class detected at the global level (e.g., fluvial plain) in a variety of more detailed coastal typologies (e.g., open coast eroding sandy shores backed by bedrock) characterized by a different sensitivity to climate change and sea-level rise. Accordingly, the information provided by regional indicators can support decision-makers in improving the management of coastal resources by considering the potential impacts of climate change and in the definition of appropriate actions to reduce inundation risks, to avoid the potential loss of valuable wetlands and vegetation and to plan the nourishment of sandy beaches subject to erosion processes.  相似文献   
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