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1.
There is a widespread recognition of the need for better information sharing and provision to improve the viability of end-of-life (EOL) product recovery operations. The emergence of automated data capture and sharing technologies such as RFID, sensors and networked databases has enhanced the ability to make product information; available to recoverers, which will help them make better decisions regarding the choice of recovery option for EOL products. However, these technologies come with a cost attached to it, and hence the question ‘what is its value?’ is critical. This paper presents a probabilistic approach to model product recovery decisions and extends the concept of Bayes' factor for quantifying the impact of product information on the effectiveness of these decisions. Further, we provide a quantitative examination of the factors that influence the value of product information, this value depends on three factors: (i) penalties for Type I and Type II errors of judgement regarding product quality; (ii) prevalent uncertainty regarding product quality and (iii) the strength of the information to support/contradict the belief. Furthermore, we show that information is not valuable under all circumstances and derive conditions for achieving a positive value of information.  相似文献   

2.
Background Sustainable development (SD) is a common concept. Knowledge and attitudes are essential in the SD process. This study assesses the knowledge, attitudes, and practices (KAP) of local people about SD. Aim To study the factors that influence the understanding of the concept, contents, and indicators of different aspects affecting the health and environmental issues. Methods A cross-sectional study was carried out from June to July 2007 among 546 households in the Quang Tri province. Data were gathered on basis of socio-demographic variables, namely age, gender, education, occupation, income, and region. Chi square tests and multivariate analysis were performed on the obtained data. The data were cleaned and analysed using SPSS 15.0 for windows. Results Occupation is related to knowledge, attitude, or practice. Income is related to knowledge or practice. Gender related to only attitude. Lastly, region is related to attitude or practice. The proportion of wrong understanding about SD is 2.0 times (95% CI: 1.3; 3.1, p < 0.001) higher than that of the people who have good understanding about it. The rate of willingness to do any related SD programmes of the people who understanding is 2.1 times (95% CI: 1.4; 3.2, p < 0.001) higher than that of the people who have bad one. Conclusions This study shows that knowledge on sustainability of the local communities is low. Occupation and income influence understanding of SD more than region, age, gender, and education. Most of the local people who do not understand SD in general, do not want to participate or act in SD programmes.  相似文献   

3.
Sustainability-related issues present significant financial, strategic, compliance and operational risks to manufacturers. Many of these risks directly or indirectly result from the way a product is designed and managed across its life cycle. Assessing sustainability risk (S R) at the product design stage is crucial for the development of products that both minimise sustainability risk exposure and are environmentally sustainable. Managing the costs associated with these risks requires risk management intervention at the design stage before these costs are committed throughout the life cycle (production, use, end-of-life). The goal of the sustainability risk assessment (SRA) methodology is to provide an approach to comparing the financial cost of a ‘sustainable product’ vs. an ‘unsustainable product’, by factoring in the effects of S R on life-cycle cost. The SRA methodology demonstrates that, in some cases, sustainable products cost less than unsustainable products when sustainability risk is considered in the costing analysis. This paper outlines the first step of the SRA methodology, which is a process for identifying S R inherent in the product life cycle. Once key risks are identified, the subsequent steps of the SRA assess and prioritise these risks for treatment through changes to product design and materials composition.  相似文献   

4.
The United States Department of Energy (DOE) currently has in place a radiation dose standard for the protection of aquatic animals, and is considering additional dose standards for terrestrial biota. These standards are: 10 mGy/d for aquatic animals, 10 mGy/d for terrestrial plants, and, 1 mGy/d for terrestrial animals. Guidance on suitable approaches to the implementation of these standards is needed. A screening methodology, developed through DOE's Biota Dose Assessment Committee (BDAC), serves as the principal element of DOE's graded approach for evaluating radiation doses to aquatic and terrestrial biota. Limiting concentrations of radionuclides in water, soil, and sediment were derived for 23 radionuclides. Four organism types (aquatic animals; riparian animals; terrestrial animals; and terrestrial plants) were selected as the basis for development of the screening method. Internal doses for each organism type were calculated as the product of contaminant concentration, bioaccumulation factor(s) and dose conversion factors. External doses were calculated based on the assumption of immersion of the organism in soil, sediment, or water. The assumptions and default parameters used provide for conservative screening values. The screening methodology within DOE's graded approach should prove useful in demonstrating compliance with biota dose limits and for conducting screening assessments of radioecological impact. It provides a needed evaluation tool that can be employed within a framework for protection of the environment.  相似文献   

5.
To test the hypothesis that morphological disparity increases while taxonomic diversity decreases in a radioactively contaminated environment, the relationship of these parameters was studied in communities (taxocenes) of rodents living in the Southern Urals in the zone of influence from the Eastern Ural Radioactive Trace (EURT) (2003–2008). Young of the year of six rodent species (98 samples) were examined in the background (control) area (0.2 Ci/km2) and in the impact area polluted with radionuclides from the EURT (750 Ci/km2). The dynamics of morphological disparity (MD), assessed with regard to average values of five exterior characters, was compared between the control and impact taxocenes. Taxonomic (taxocenotic) diversity was estimated with the Shannon index (H). Morphological disparity was found to increase significantly at low rodent abundance (in conditionally unfavorable years) and decrease at high abundance, with the value of MD in the impact taxocene being significantly higher. A negative correlation between MD and H was revealed (r = −0.70), in conformity with the above hypothesis. Discordance (difference in direction) of annual changes in the test parameters, with H increasing while MD decreases (or vice versa) was observed in unfavorable years; it can be used as an indicator of conditions unfavorable for rodent taxocenes.  相似文献   

6.
This study investigated the use of a screening procedure to provide a ranking index (RI) for characterizing polynuclear aromatic (PNA) species in atmospheric samples. The ranking procedure employs a cost-effective and rapid screening technique based on synchronous luminescence spectroscopy. The efficacy and usefulness of the ranking procedure are demonstrated by comparing the RI values with data expressed in terms of the benzene-soluble standard, benzo[a]pyrene values, and the total content of fourteen PNA compounds.  相似文献   

7.
This paper is the first recorded economic value of living fossil,an evaluation of the basic economic value of Lingula,based on the direct utilization of households for food and sale.Twenty-one local fishermen who collected Lingula in Trat Province were focused on by using interview questionnaires.The animal habitats are influenced by the encroachers’age,gender and harvest method.The total economic value in 2011 was around two million baht.Those who possess fishing gear and have more money can have greater access to the product The local communities in Nong Khunsong sub-district are successful in collecting the Lingula and in doing local business.The market channel analysis is conducted at local,provincial and national levels and short market chains are demonstrated in the form of a wholesale market in the Lingula trade.This represents significant consumption by the local communities.The study further recommends sustainable conservation and management efforts at a local scale.  相似文献   

8.
Variations in the parameters of the life cycle in freshwater prawns of the genus MacrobrachiumBate and some populations of the species Macrobrachium nipponense(De Haan) were analyzed comparatively. Using factor analysis, these parameters were systematized and expressed through two factors. The first factor is related to the parameters of larval development and the dimensions of an egg, and the second, to the length of adults and their fecundity. The greatest differences in the values of intrageneric and intraspecific variation of parameters are noted for the dimensions of larval stages. It is assumed that the formation of a species proceeds primarily through the appearance of adaptations at larval stages.  相似文献   

9.
BackgroundAlthough antibiotic use during early life has been demonstrated to be related to the altered adipogenesis in later life, limited data are available for the effect of antibiotic exposure in school children on adiposity from various sources, including from the use or contaminated food or drinking water.ObjectiveTo explore the association between the internal exposure of antibiotics from various sources and adipogenesis in school children using the biomonitoring of urinary antibiotics.MethodsAfter 586 school children aged 8–11 years were selected from Shanghai in 2013, total urinary concentrations (free and conjugated) of 21 common antibiotics from six categories (macrolides, β-lactams, tetracyclines, fluoroquinolones, sulfonamides, and phenicols), including five human antibiotics (HAs), two antibiotics preferred as HA, four veterinary antibiotics (VAs), and ten antibiotics preferred as VA, were measured by ultra-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry. Creatinine-corrected urinary concentrations of antibiotics were used to assess their exposure. Overweight or obesity was determined by the body mass index or waist circumference-based criteria deriving from national data.ResultsAll 21 antibiotics were found in urines with the overall detection frequency of 79.6%. The multinomial logistic regression analyses showed the significant associations of overweight and obesity with the exposure to VAs and antibiotics preferred as VA, but not with HAs or antibiotics preferred as HA. After adjusted for a number of obesity-relevant variables, the odds ratios (95% confidence interval) of BMI-based obesity risk of tertiles 2 and 3 of urinary concentrations relative to tertile 1 were respectively 2.54 (1.27, 5.07) and 2.92 (1.45, 5.87) for florfenicol, 0.57 (0.12, 2.63) and 3.63 (1.41, 9.32) for trimethoprim, and 3.00 (1.56, 5.76) and 1.99 (0.99, 4.01) for sum of veterinary antibiotics. Similar results were found when the outcome used WC-based obesity risk. The associations were sex related and mainly observed in boys.ConclusionsSome types of antibiotic exposure, which were mainly from food or drinking water, were associated with an increased risk of obesity in school children. Due to the cross-sectional design, more longitudinal and experimental studies are warranted to further test these findings.  相似文献   

10.
Variation of bilateral leaf structures in Middle Ural cenopopulations of the weeping birch (Betula pendula Roth.) growing in gradients of industrial pollution was studied to test the efficiency of a new method of population and individual phenogenetic monitoring allowing an indirect assessment of developmental destabilization by segregating the variance of total asymmetry (TA R 2) into its additive components, the variances of fluctuating asymmetry (FA R 2) and directional asymmetry (DA R 2). The method was tested in the impact zones of two copper-smelting plants in the Middle Urals. The degree of impact was characterized by the index of technogenic pollution (ITP) reflecting the average total contents of 15 water-soluble pollutants in snow samples. The level of asymmetry was estimated from the numbers of denticles with incoming veins (dentovenal elements) on the left and right leaf margins. Spearman’s coefficient of rank correlation between the group values of variance in fluctuating asymmetry (FA R 2) and corresponding ITP values reached r S = 0.914 (p < 0.001), providing evidence that the method is highly appropriate for ecological indication of the phenogenetic response of trees to environmental pollution.  相似文献   

11.
Studies on the distribution of the forms of heavy metals (HMs) in the humus soil horizon were performed in the Berezinskii Reserve and Braslavskie Ozera National Park. The ratios of active to inert HM forms (with trace values of the mobile form) in these areas proved to be similar and independent of the total HM content. The calculated coefficients of technogeneity (Kt and Xt) and mobility (Km and Xm) are proposed, which reflect the natural ratio between the forms of HMs in the Northern and Central lithogeochemical provinces of Belarus.  相似文献   

12.
Recent reviews have established benchmark values for transfer factors that describe radionuclide transfer from plants to animal food product such as milk, eggs and meat. They also illustrate the paucity of data for some elements and some food products. The present study quantified transfer data using indigenous elements measured in dairy, poultry and other livestock farms in Canada. Up to 62 elements are reported, with particular emphasis on iodine (I) because of the need to accurately assess the behaviour of 129I from disposal of nuclear fuel waste. There was remarkable agreement with the literature values, and for many elements the present study involved many more observations than were previously available. Perhaps the most important observation was that product/substrate concentration ratios (CR) were quite consistent across species, whereas the traditional fractional transfer factors (TF, units of d kg−1 or d L−1) necessarily vary with body mass (feed intake). This suggests that for long-term assessments, it may be advisable to change the models to use CR rather than TF.  相似文献   

13.
Thirty-seven dose-response curves involving animal and plant material, subjected to treatment with cancerogenic chemicals and low-energy transfer ionizing radiation, have been gathered from the literature. In addition, one experiment in which a nutritional factor was used has been included in the results.Our calculations indicate that all the responses appear to fit the equation f = (Dn)/(Kn + Dn) where f is the fraction of subjects affected, D is the dose applied, and K is a constant characteristic of the cancerogen or treatment. Both of these parameters are raised to the nth power and result in a family of curves. The values of n were found to range between 0.33 and 3.13 with a value close to 1.00 (linear at low doses) in only three cases. Data from these 38 reports are displayed in a logarithmic plot on a single graph. In addition to the values of n and K, as well as the dosages and responses needed to construct this graph, are presented in two tables.Our mathematical treatment of the published data shows an unexpected universality of biological behavior that may be helpful in the extrapolation of experimental data to humans.  相似文献   

14.
The variability of the sorption properties (characterized by the distribution coefficient Kd) of a forest soil for Cs, Zn, Sr, Co, Cd, Ce, Ru, Tc, and I were determined along a transect of 150 m in regular intervals of 3 m. Radioactive tracers were used to ensure trace concentrations of these elements. For comparison, for each soil sample the loss on ignition, as a measure of the soil organic matter content, and the pH were also determined. On average, the Kd values increase in the sequence Tc < I < Ru ≈ Co ≈ Zn ≈ Sr < Cd < Ce < Cs; the spatial variability in the sequence I < Zn ≈ Sr ≈ Co ≈ Cd ≈ Ru ≈ Tc < Cs, and I ≈ Ce < Tc. Correlation analysis revealed that, when moving along the transect, the Kd values for some elements changed in a similar, and for others in a dissimilar pattern. In a few cases a correlation between the pH or the loss on ignition and the Kd values was also present. The spatial structure of the data was examined by semivariograms. For the elements Co, Cd, Zn, and Sr, the Kd values showed an almost periodic behaviour along the transect, which is probably due to periodic changes of some soil properties in a forest with regularly spaced trees.  相似文献   

15.
In the rural areas of developing countries palms are major sources of many products. One of these is palm wine, which has an important role for nutrition, income and social life. In the Côte d'Ivoire (West Africa), palm wine is extracted from three different species: Borassus aethiopum Mart., Raphia hookeri Mann & Wendland and Elaeis guineensis Jacq. As the extraction methods are destructive, palm stands are locally threatened by extinction. This could have serious consequences not only for the nutritional situation of the population but also for their income. Field visits were conducted in order to assess the degree of sustainability of palm wine extraction in eight villages of Côte d'Ivoire's three major agro-ecozones. Based on the annual palm wine need for consumption and commercialisation and on the availability of palms, a sustainability index was calculated for each palm species in each village. The occurrence of palm trees depends on the vegetation type. B. aethiopum is a typical savanna tree (> 20 palms per hectare) and is almost absent in other vegetation types. In 75% of the villages the exploitation of B. aethiopum is not sustainable. The preferred vegetation type for R. hookeri is the forest along the rivers (> 33 palms per hectare) compared to the other vegetation types of the forest zone (< 5 palms per hectare). Due to the high preference for the palm wine of this species its exploitation is not sustainable in any of the selected villages. The distribution of E. guineensis depends mostly on human activities, the main vegetation types being plantations (34 palms per hectare), fallow land and cultivated fields (15 palms per hectare) and the forest along the rivers (31 palms per hectare). The exploitation of this species is in general sustainable throughout all ecozones with some rare exceptions.  相似文献   

16.
Abstract

The study tries to set up a system to extract strategic environmental assessment (SEA) in exploitation of regional development based on the present situation of environmental assessment in China. First, the article summarizes the emphasis and deficiency of international academic community’s SEA research in the past 10 years. Based on this, the article puts forward the concept and evaluation principles of regional strategic environmental assessment (RSEA). Then the article expounds the necessity of carrying out RSEA. After that, the article discusses in detail the process of RSEA, which includes defining evaluation scope, describing regional background, combing strategic behavior, designing development scenarios, predicting the pressure on environment, assessing environmental impact, screening alternatives and proposing regulation and control schemes.  相似文献   

17.
In the framework of a 222Rn screening campaign that was carried out in 58 public secondary schools in Galicia (NW Spain), the largest radon-prone area in the Iberian Peninsula, a positive correlation between indoor 222Rn concentration and outdoor gamma exposure rate was obtained. A new approach to the data acquisition in screening surveys was tested, improving the performances of this type of study and gathering useful data for future remedial actions. Using short-period detectors (charcoal canisters) firstly, in order to detect places showing 222Rn concentrations over 400 Bq m−3, the number of locations to be measured with long-period detectors (etched track detectors) is reduced. In this screening campaign, 34% of the schools surveyed presented at least one site exceeding the 400 Bq m−3 recommended action level established by the EU, and 15% had at least one site with 222Rn values over 800 Bq m−3. The maximum value recorded was 2084 ± 63 Bq m−3. These results are discussed and compared with data obtained in schools of several countries with similar geology. Seven schools were also studied for seasonal variations of 222Rn activity concentration. The results were not conclusive, and no significant correlation between season and 222Rn concentration was established. Finally, a continuous 222Rn concentration monitor was placed in the secondary school exhibiting a mean value of the 222Rn concentration very close to 400 Bq m−3. Maximum 222Rn concentration values were found to occur at times when the school was unoccupied.  相似文献   

18.
The woody species known, used, and preferred as fuelwood were examined in three rural communities within the county of Soledade, Paraíba State, NE Brazil. Ethnobotanical information was collected using semi-structured interviews with more than 90% of the local households (55 adult residents; 31 women, and 24 males). The interviewees cited 36 plant species as fuelwoods, distributed among 30 genera and 15 families, in addition to two unidentified plants. The plant families represented by the largest numbers of species were Euphorbiaceae, Anacardiaceae, Mimosaceae, Caesalpiniaceae, Sapotaceae, and Fabaceae. The species Caesalpinia pyramidalis Tul. (“catingueira”) was cited with the greatest frequency in all three communities. Within the communities we found significant differences on the number of plants cited and actually used (p < 0.05), indicating that the residents knew more fuelwood species than they effectively harvest. The different distances from the communities to the urban centers were not related to differences on the use or the size of the stocks of fuelwood. Additionally, the study revealed that the communities examined still maintain a significant knowledge of the use of energy-providing plants in spite of the widespread use of liquefied petroleum gas (LPG). Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   

19.
The purpose of the present work is to asses the possibility of detecting changes in soil organic carbon (SOC) at the end of the 5-years of the first Commitment Period (CP) of the Kyoto Protocol of the United Nation’s Framework Convention on Climate Change (1 January, 2008–31 December, 2012), by both direct measurement and the use of an opportunely evaluated SOC model, CENTURY. The investigated soil is young, developed since 28 years on virtually C-free spoil banks and under the influence of two managed forest stands, one a mix of English oak (Quercus robur L.) and Italian alder (Alnus cordata Loisel.) and the other pure English oak. The SOC stock of either stand was monitored since the time the stands were planted in 1981, and it was used together with other parameters for the model evaluation, while the future projections for the end of the first (2012) and second (2017) CP were made according to two extreme IPCC climatic scenarios: A1F1, the most dramatic, and B2, among the less impacting. Direct SOC measurements performed at the beginning and at the end of a time frame equivalent to a commitment period (2004–2008) had not shown significant variations in either stands. Compared to the 2008 SOC stock, in both stands the model shows variations at the end of the first CP from 0.7 to 1.8 Mg C ha−1 for the A1F1 scenario and from 0.3 to 1.7 Mg C ha−1 for the B2. These variations are within the standard deviations of the C stocks measured in 2008. On the contrary, at the end of the second CP, the modelled SOC increments range from 2.5 to 3.6 Mg C ha−1 (A1F1) or from 1.9 to 3.4 Mg C ha−1 (B2), indicating the possibility to detect the SOC changes by direct measurement, since the values well agree with the minimum detectable variation estimated for both sites in 3.3–4.5 Mg C ha−1. This work shows that SOC stock changes measured directly in the field can be minimal at the end of both CPs, and that CENTURY well simulates the SOC dynamics of the stands. The use of such a model, validated at long-term experimental sites, hence represents an effective tool for estimating future changes in SOC amounts in support of direct measurements when a short period of time, such as the CP, is considered.  相似文献   

20.
Sensitivity to the pyrethroids deltamethrin and esfenvalerate (aqueous solution) and LC50 have been determined in acute (96-h) toxicological tests on mayfly larvae (Cloeon dipterum and Caenis miliaria), damselfly larvae (Lestes sponsa and Cordulia aenea), and juveniles from a laboratory culture of Daphnia magna. Sensitivity to deltamethrin increases in the series C. aenea (Odonata) < D. magna (Cladocera) < L. sponsa (Odonata) < C. miliaria(Ephemeroptera) < C. dipterum (Ephemeroptera), and that to esfenvalerate, in the series C. aenea < D. magna < L. sponsa C. miliaria C. dipterum. The values of LC50 about 0.01 g/l determined for mayfly larvae are below those known for various hydrobionts from the literature, indicating a very high sensitivity of these insects to pyrethroids.  相似文献   

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