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991.
Aging urban infrastructure is a common phenomenon in industrialized countries. The urban water supply pipeline network in the city of Oslo is an example. Even as it faces increasing operational, maintenance, and management challenges, it needs to better its environmental performance by reducing, for instance, the associated greenhouse gas emissions. In this article the authors examine the environmental life cycle performance of Oslo's water supply pipelines by analyzing annual resource consumption and emissions as well as life cycle assessment (LCA) impact potentials over a period of 16 years, taking into account the production/manufacture, installation, operation, maintenance, rehabilitation, and retirement of pipelines. It is seen that the water supply pipeline network of Oslo has already reached a state of saturation on a per capita basis, that is, it is not expanding any more relative to the population it serves, and the stock is now rapidly aging. This article is part of a total urban water cycle system analysis for Oslo, and analyzes more specifically the environmental impacts from the material flows in the water distribution network, examining six environmental impact categories using the SimaPro (version 7.1.8) software, Ecoinvent database, and the CML 2001 (version 2.04) methodology. The long‐term management of stocks calls for a strong focus on cost optimization, energy efficiency, and environmental friendliness. Global warming and abiotic depletion emerge as the major impact categories from the water pipeline system, and the largest contribution is from the production and installation phases and the medium‐size pipelines in the network.  相似文献   
992.
The potentially hazardous effects of agricultural pesticide usage in the Crocodile (west) Marico catchment were evaluated using the Danio rerio and Daphnia pulex lethality, Selenastrum capricornutum growth inhibition and the Ames mutagenicity plate incorporation assays. Hazard assessment categories are proposed to standardise the output of the different toxicity assessments. Sites were categorised according to the toxicity hazard indicated and were related to the gradients of agricultural land-use intensity at each site. Intensive agricultural sites showed the highest effects to all tested biota. Receiving water at urban sites associated with increased nutrients and lowest pesticide usage showed few adverse effects, while the relatively unimpacted site indicated no hazard to any organism, and only a slight stimulation to algal growth. Weighted hazard scores indicated that the unimpacted sites were least hazardous, falling within a B category, the urban sites were moderately hazardous (C category), and the agricultural sites (D category) had the highest potential impacts on aquatic organisms. This study demonstrated the usefulness of using the hazard assessment approach and the role it could play in assessing site-specific potential toxicity hazards of river water impacted by agrochemicals. It can be used together with other assessment methods, such as biological indices, in a tiered approach.  相似文献   
993.
The field of education in the United States is in a period of unprecedented change. Educators in all disciplines are challenged to understand and respond to the waves of reform sweeping over the national education landscape. Linking these reforms to meaningful outcomes that will produce more rigorous and effective measures of quality and performance in our schools is an ongoing goal for all educators as they work to respond to calls for educational reform. Changes in the general field of education have direct implications for arts education policy and practice. Arts educators find themselves in the position of making sense of these landmark reforms and changes in the context of arts education and determining what courses of action and responses they should pursue on the road to meaningful reform. This report provides an overview of a selected number of contemporary developments in the general field of education, brief summaries of consequential studies and education-related reports, and an examination of some policy issues these developments and reports raise for arts educators as they work to shape the future landscape of arts education.  相似文献   
994.

Objective

The aim of this study was to describe the psychometric evaluation of the Orofacial Pain Scale for Non‐Verbal Individuals (OPS‐NVI) as a screening tool for orofacial pain in people with dementia.

Background

The OPS‐NVI has recently been developed and needs psychometric evaluation for clinical use in people with dementia. The pain self‐report is imperative as a reference standard and can be provided by people with mild‐to‐moderate cognitive impairment.

Methods

The presence of orofacial pain during rest, drinking, chewing and oral hygiene care was observed in people with mild cognitive impairment (MCI) and dementia using the OPS‐NVI. Participants who were considered to present a reliable self‐report were asked about pain presence, and in all participants, the oral health was examined by a dentist for the presence of potential painful conditions. After item‐reduction, inter‐rater reliability and criterion validity were determined.

Results

The presence of orofacial pain in this population was low (0%‐10%), resulting in an average Positive Agreement of 0%‐100%, an average Negative Agreement of 77%‐100%, a sensitivity of 0%‐100% and a specificity of 66%‐100% for the individual items of the OPS‐NVI. At the same time, the presence of oral problems, such as ulcers, tooth root remnants and caries was high (64.5%).

Conclusion

The orofacial pain presence in this MCI and dementia population was low, resulting in low scores for average Positive Agreement and sensitivity and high scores for average Negative Agreement and specificity. Therefore, the OPS‐NVI in its current form cannot be recommended as a screening tool for orofacial pain in people with MCI and dementia. However, the inter‐rater reliability and criterion validity of the individual items in this study provide more insight for the further adjustment of the OPS‐NVI for diagnostic use. Notably, oral health problems were frequently present, although no pain was reported or observed, indicating that oral health problems cannot be used as a new reference standard for orofacial pain, and a regular oral examination by care providers and oral hygiene care professionals remains indispensable.  相似文献   
995.
Background, aim and scope  Considerable debate surrounds the assessment of the environmental impacts and the ethical justification for providing a year-round supply of fresh produce to consumers in the developed countries of northern Europe. Society is seeking environmentally sustainable supply chains which maintain the variety of fresh food on offer throughout the year. This paper compares the environmental impacts of different supply chains providing lettuce all year round to the UK and considers consumers' meanings of—and attitudes to—available options. Lettuce has been selected as a case study as its consumption has grown steadily during the last two decades and the supply chains through cold months are protected cropping in the UK and field cropping in Spain; during warm months, lettuce is sourced from field cropping in the UK. Materials and methods  Data were collected from farms supplying each of these supply chains, and life cycle assessment methodology was used to analyse a range of impacts associated with producing (from plant propagation to harvesting and post-harvest cooling) and delivering 1 kg of lettuce to a UK Regional Distribution Centre (RDC). The downstream stages (i.e. retailing, consumption and waste management) are the same regardless of the origin of the product and were omitted from the comparison. The impacts considered included potential to induce global warming and acidification as well as three inventory indicators (primary energy use, land use and water use). Qualitative data were collected in order to assess the consumer considerations of purchasing lettuce also during winter. Results  Importation of Spanish field-grown lettuce into the UK during winter produced fewer greenhouse gas (GHG) emissions than lettuce produced in UK-protected systems at that time (0.4–0.5 vs. 1.5–3.7 kg CO2-eq/kg lettuce in RDC). Refrigerated transport to the UK was an important element of the global warming potential associated with Spanish lettuce (42.5% of emissions), whilst energy for heating dominated the results in UK-protected cultivation (84.3% of emissions). Results for acidification were more variable and no overall trends are apparent. Results from qualitative social analysis revealed complex and multidimensional meanings of freshness and suggested that the most striking seasonal variation in vegetable/salad eating was a tendency to consume more salads in the summer and more cooked vegetables in the winter, thus suggesting that in-home consumption alone cannot explain the rise in winter imports of lettuce to the UK. Discussion  UK field-grown lettuce had the lowest overall environmental impact; however, those lettuces are only available in summer, so consumers therefore need to either accept the environmental impacts associated with eating lettuce in the winter or to switch consumption to another food product in the winter. When lettuces were field-grown in Spain and then transported by road to the UK, the overall impacts were similar to the UK field lettuces. The variation within farms of the same country employing different cultivation regimes and practices was bigger than between farms of different countries. Conclusions  This paper has explored the environmental consequences of consuming lettuce year-round in the UK. Whilst recognising the small sample size, the comparative analysis of the different supply chains does suggest that seasonality can be an important variable when defining the best choice of lettuce from an environmental point of view. Recommendations and perspectives  Further studies considering more production sites and product types are required to obtain conclusions whose general validity is clear and for different types of fresh produce. A clear distinction to be made in such studies is whether crops are produced in open fields or under protection. New characterisation methods are needed for environmental impacts derived from the use of key agricultural resources such as land and water. Social studies to investigate consumer preferences and the possibility of moving to more seasonal diets should be an integral part of these studies using samples composed of both urban and rural consumers and using a mixed methodology with both quantitative and qualitative components.
Almudena HospidoEmail:
  相似文献   
996.
This article presents a model that quantifies the health loss and benefit triggered by the life cycle of a diesel engine. The health loss and benefit are expressed in the form of disability‐adjusted life years (DALY), a metric used by the World Health Organization to conduct health impact assessments. In order to quantify the health loss, life cycle assessment methodology is applied. To estimate the health benefit, the relationship between DALY per capita and gross domestic product (GDP) per capita is modeled. The change in GDP per capita, resulting from the change in the level of employee compensation caused by the life cycle of the diesel engine, is used to estimate the change in the level of DALY per capita. An economic input‐output model is applied to estimate the amount of employee compensation required over the life cycle of the diesel engine. This study concludes that the health benefit achieved by the socioeconomic growth, triggered by the life cycle of the diesel engine, is higher than the health loss caused by the pollutions produced over the life cycle of the diesel engine. Furthermore, the results support findings in the literature that socioeconomic growth generates a higher health benefit in a lower‐income country than in a higher‐income country. This also might be one of the reasons for another statement found in the literature that developing countries put higher priorities on economic development.  相似文献   
997.
Habitat structure has been implicated as a source of bias for pitfall-trap data but most evidence is observational or anecdotal. This study used an experimental approach to quantify biases due to habitat structure. In a randomized block design, I manipulated native grassland to create three types of habitat structure and measured pitfall-trap catches of grassland ants. Small patches of modified habitat were surrounded by otherwise unmodified grassland with the assumption that population density remained unaffected by the modification and that the effects observed were due to changes in trappability. I assessed magnitude, direction, predictability, and consistency of bias for the following types of data: population abundance for single species, relative abundance among species, species composition of assemblages, and species richness. The magnitude of the bias in population abundance was large for most species. However, since the direction of the bias varied predictably with habitat structure, pitfall-trap data can be used to judge differences in population abundance in some situations. The magnitude of the bias in relative abundance was less than for abundance. However, there was inconsistency in the direction and magnitude of bias among species. Thus, interpretation of relative abundance data in pitfall-trap studies may be compromised. Species richness and species composition were biased by habitat structure but were affected significantly only when the groundcover was very dense, suggesting a threshold effect of habitat structure. To help to interpret survey data, pitfall-trap studies should routinely measure attributes of habitat structure and incorporate an experimental component to characterize the bias.  相似文献   
998.
1. Natural variation in environmental parameters, as well as practical constraints in study design and sampling methodology, often pose difficulties in treating impact assessments in river catchments as controlled field experiments. It is frequently impossible to develop robust relationships between reference and test stations prior to the onset of an impact and the range of statistical tools which can be adopted in data analysis to detect a change or disturbance is limited. 2. In an attempt to overcome these problems we introduce a novel disturbance index to assess the impact of landuse activities on river systems. The index identifies differences in hydrochemical parameters and macroinvertebrate community metrics between reference and test stations (at a set level of significance). This approach allows for objective assessment of the occurrence and direction of change as well as the duration of an impact. The disturbance index can be applied at different scales – for a single stream, a catchment or a region. 3. In this paper we describe the derivation of the index and illustrate its utility through worked examples. We use the index to assess impact of clearfelling on hydrochemical parameters such as hydrogen ion concentration, total hardness, suspended solids, conductivity and nitrate concentration as well as on macroinvertebrate parameters including abundance, richness, reciprocal of Simpson's diversity index, evenness, Ephemeroptera/Plecoptera/Trichoptera (EPT) richness and percentage of EPT taxa. 4. The sensitivity of the disturbance index changes with scale of application however, and the clearfelling (CF) index has proven sensitive to the detection of even quite small changes, although in these cases ecological significance should be considered. We show that the CF index, particularly when derived from a regional scale, is a conservative index but is very robust to variation in the number of samples used in its derivation. The application of the index corresponded very well with the application of more standard statistical approaches. We believe that the index can thus be applied to other impact studies with similar project design.  相似文献   
999.
Based on Remote Sensing (RS), Geographical Information Systems (GIS), and the Spatial Principal Component Analysis (SPCA) method, the integrated assessment and changes in the ecological environment of Daning River Watershed are studied in this paper. The watershed is located in the Three Gorge Area in China. The result of the integrated assessment showed that level 9 had the biggest proportion in the year 1990, which was about 40%. In the year 2000, however, there were no levels with a proportion significantly bigger than the others. By comparing the assessment results in 1990 and 2000, it is discovered that the ecological environment in Daning River Watershed in 1990 was better than that in 2000. __________ Translated from Journal of Beijing Normal University (Natural Science), 2006, 42(2): 200–203 [译自: 北京师范大学学报 (自然科学版)]  相似文献   
1000.
Product Environmental Life-Cycle Assessment Using Input-Output Techniques   总被引:1,自引:0,他引:1  
Life-cycle assessment (LCA) facilitates a systems view in environmental evaluation of products, materials, and processes. Life-cycle assessment attempts to quantify environmental burdens over the entire life-cycle of a product from raw material extraction, manufacturing, and use to ultimate disposal. However, current methods for LCA suffer from problems of subjective boundary definition, inflexibility, high cost, data confidentiality, and aggregation.
This paper proposes alternative models to conduct quick, cost effective, and yet comprehensive life-cycle assessments. The core of the analytical model consists of the 498 sector economic input-output tables for the U.S. economy augmented with various sector-level environmental impact vectors. The environmental impacts covered include global warming, acidification, energy use, non-renewable ores consumption, eutrophication, conventional pollutant emissions and toxic releases to the environment. Alternative models are proposed for environmental assessment of individual products, processes, and life-cycle stages by selective disaggregation of aggregate input-output data or by creation of hypothetical new commodity sectors. To demonstrate the method, a case study comparing the life-cycle environmental performance of steel and plastic automobile fuel tank systems is presented.  相似文献   
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