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In a recent letter to the editor, Jørgensen et al. questioned that life cycle costing (LCC) is relevant in life cycle-based sustainability assessment (LCSA). They hold the opinion that environmental and social aspects are sufficient. We argue that sustainability has three dimensions: environment, economy, and social aspects in accordance with the well-accepted “three pillar interpretation” of sustainability, although this is not verbally stated in the Brundtland report (WCED 1987). An analysis of the historical development of the term “sustainability” shows that the economic and social component have been present from the beginning and conclude that LCSA of product systems can be approximated by LCSA = (environmental) LCA + (environmental) LCC + S-LCA where S-LCA stands for social LCA. The “environmental” LCC is fully compatible with life cycle assessment (LCA), the internationally standardized (ISO 14040 + 14044) method for environmental product assessment. For LCC, a SETAC “Code of Practice” is now available and guidelines for S-LCA have been published by UNEP/SETAC. First examples for the use of these guidelines have been published. An important practical argument for using LCC from the customers’ point of view is that environmentally preferable products often have higher purchasing costs, whereas the LCC may be much lower (examples: energy saving light bulbs, low energy houses, and cars). Also, since LCC allows an assessment for different actor perspectives, the producers may try to keep the total costs from their perspective below those of a conventional product: otherwise, it will not succeed at the market, unless highly subsidized. Those are practical aspects whichfinally decide about success or failure of “sustainable” products. Whether or not an analysis using all three aspects is necessary will depend on the exact question. However, if real money flows are important in sustainability analysis of product systems, inclusion of LCC is advisable.  相似文献   

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Most research in human behavioral ecology has been acultural, which raises the question of how best to incorporate the concept of culture into this approach. A necessary step in this direction is to pare the culture concept down to its ideational elements, excluding behavior and its material products (Durham 1991; Geertz 1973; Keesing 1974). The cultural and reproductive success hypothesis, though empirically successful (Irons 1993), is not a model for all of culture because of widespread discrepancies between behavior and culture to which it does not call attention. Cultural transmission models are also weakened by such discrepancies, but, more importantly, such models are most relevant to phenomena different from those central to human behavioral ecology. A better way to incorporate culture into human behavioral ecology is to see it as the context of human action and as a tool people use in social manipulation. The study of signal systems is a key to an understanding of social manipulation and to the incorporation of culture into human behavioral ecology. Examples of the manipulation of culture for reproductive benefit include Yanomamö kin term manipulation (Chagnon 1988), incest rules (Thornhill 1990, 1991), and the derogation of sexual competitors (Buss and Dedden 1990). The human behavioral ecological study of social manipulation in cultural contexts needs to be expanded. Two phenomena that might shed light on such manipulation are the Rashomon effect and the audience effect.  相似文献   

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Is there a common chemical model for life in the universe?   总被引:2,自引:0,他引:2  
A review of organic chemistry suggests that life, a chemical system capable of Darwinian evolution, may exist in a wide range of environments. These include non-aqueous solvent systems at low temperatures, or even supercritical dihydrogen-helium mixtures. The only absolute requirements may be a thermodynamic disequilibrium and temperatures consistent with chemical bonding. A solvent system, availability of elements such as carbon, hydrogen, oxygen and nitrogen, certain thermodynamic features of metabolic pathways, and the opportunity for isolation, may also define habitable environments. If we constrain life to water, more specific criteria can be proposed, including soluble metabolites, genetic materials with repeating charges, and a well defined temperature range.  相似文献   

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Purpose

Decisions based on life cycle sustainability assessment (LCSA) pose a multi-criteria decision issue, as impacts on the three different sustainability dimensions have to be considered which themselves are often measured through several indicators. To support decision-making at companies, a method to interpret multi-criteria assessment and emerging trade-offs would be beneficial. This research aims at enabling decision-making within LCSA by introducing weights to the sustainability dimensions.

Methods

To derive weights, 54 decision-makers of different functions at a German automotive company were asked via limit conjoint analysis how they ranked the economic, environmental, and social performance of a vehicle component. Results were evaluated for the entire sample and by functional clusters. Additionally, sustainability respondents, i.e., respondents that dealt with sustainability in their daily business, were contrasted with non-sustainability respondents. As a last step, the impact of outliers was determined. From this analysis, practical implications for ensuring company-optimal decision-making in regard to product sustainability were derived.

Results and discussion

The results showed a large spread in weighting without clear clustering. On average, all sustainability dimensions were considered almost equally important: the economic dimension tallied at 33.5%, the environmental at 35.2%, and the social at 31.2%. Results were robust as adjusting for outliers changed weights on average by less than 10%. Results by function showed low consistency within clusters hinting that weighting was more of a personal than a functional issue. Sustainability respondents weighted the social before the environmental and economic dimension while non-sustainability respondents put the economic before the other two dimensions. Provided that the results of this research could be generalized, the retrieved weighting set was seen as a good way to introduce weights into an operationalized LCSA framework as it represented the quantification of the already existing decision process. Therefore, the acceptance of this weighting set within the respective company was expected to be increased.

Conclusions

It could be shown that conjoint analysis enabled decision-making within LCSA by introducing weights to solve a multi-criteria decision issue. Furthermore, implications for practitioners could be derived to ensure company-optimal decision-making related to product sustainability. Future research should look at expanding the sample size and geographical scope as well as investigating the weighting of indicators within sustainability dimensions and the drivers that influence personal decision-making in regard to weighting sustainability dimensions.

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Purpose

Technologies can contribute to sustainable development (e.g., improving living conditions) and at the same time cause sustainability problems (e.g., emissions). Decisions on alternative technologies should thus ideally be based on the principle to minimize the latter. Analyzing environmental, economic, and social aspects related to technologies supports decisions by identifying the “more sustainable” technology. This paper focuses on social issues. First, it discusses the applicability of the social life cycle assessment (SLCA) guidelines for a comparative technology analysis, taking the example of two case studies in developing countries. Indicating technologies as “sustainable” also means that they are indeed operated over the expected lifetime, which, in development projects, is often not guaranteed. Consequently, social aspects related to implementation conditions should be considered in an SLCA study as well. Thus, a second focus is laid on identifying appropriate indicators to address these aspects.

Methods

First, the SLCA guidelines were examined with regard to applying this product-related approach to two real case studies (analysis of technologies/plants for water supply and for decentralized fuel production) for a comparative technology analysis. Suitable indicators are proposed. To address the second focus, a literature research on technology assessment and implementation in developing countries was conducted. Moreover, socioeconomic studies in the investigation areas of the case studies were consulted. Based on this, indicators addressing implementation conditions were identified from the SLCA guidelines and additional literature.

Results and discussion

The study shows social issues and indicators found in the SLCA guidelines and considered suitable for a comparative technology analysis in the case studies. However, for a sustainability assessment of technologies, especially in developing countries, further indicators are required to address technology implementation conditions. A set of additional social indicators like reported trust in institutions or fluctuation of personnel is proposed. Though these indicators were derived based on specific case studies, they can also be suggested to other technologies and are not necessarily limited to developing countries.

Conclusions

The study pointed out that an application of the SLCA guidelines considering the whole life cycle was not (yet) feasible for the case studies considered. This is mainly due to the lack of data. Regarding technology implementation, it was examined which indicators are available in this SLCA approach and which could additionally be integrated and applied. This is relevant as a potential contribution of technologies to sustainable development can only be achieved when the technologies are successfully implemented.  相似文献   

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Conventional culture for the detection, enumeration and identification of micro-organisms has been the traditional tool of the microbiologist. It is, however, time-consuming and labour-intensive and confirmed results often require several days of analysis. Culture may not grow the organisms being sought and for enumeration may only detect a small proportion of the total population. However, it does have the advantage of being simple to use and relatively inexpensive. It is also a direct means of assessing cell viability. Novel fluorogenic dyes and fluorgenic and chromogenic substrates have overcome some of these problems by providing a means of rapid and specific detection and enumeration whilst removing the need for subculture and confirmation tests. Immunological tests such as ELISA have significantly reduced analysis time by providing specific target organism detection. Molecular techniques have removed the need for culture. Improvements in sensitivity, and removal of the inhibitory nature of sample matrices, have allowed analysts to detect low levels of micro-organisms but the questions of viability and comparability with cultural techniques still remain. Are we about to see a change of culture in water quality assessment, or can cultural techniques be developed that reduce analysis time to a few hours and can rapid methods be used for detecting the presence and viability of organisms?  相似文献   

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《Médecine Nucléaire》2017,41(1):21-26
This is purposely an ultraprovocative title for the broad nuclear medicine community (including radiophysics and radiopharmacy) which leads us to ask questions about how we should correctly use 90Yttrium (MSY90) microspheres in the treatment of liver tumors.  相似文献   

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Purpose

This study discusses the use of parameterization within the life cycle inventory (LCI) in the wooden pallet sector, in order to test the effectiveness of LCI parametric models to calculate the environmental impacts of similar products. Starting from a single case study, the objectives of this paper are (1) to develop a LCI parametric model adaptable to a range of wooden pallets, (2) to test this model with a reference product (non-reversible pallet with four-way blocks) and (3) to determine numerical correlations between the environmental impacts and the most significant LCI parameters; these correlations can be used to improve the design of new wooden pallets.

Methods

The conceptual scheme for defining the model is based on ISO14040-44 standards. First of all, the product system was defined identifying the life cycle of a generic wood pallet, as well as its life cycle stages. A list of independent and dependent parameters was used to describe the LCI flows of a generic wooden pallet. The LCI parametric model was applied to calculate the environmental impacts of the reference product, with regard to a selection of impact categories at midpoint level (climate change, human toxicity, particulate matter formation, agricultural land occupation, fossil depletion). The model was then applied to further 11 wooden pallets belonging to the same category.

Results and discussion

The definition of a LCI parametric model based on 31 independent parameters and 21 dependent parameters streamlined the data collection process, as the information required for fulfilling the LCI are standard information about the features of the wooden pallet and its manufacturing process. The contribution analysis on the reference product revealed that the most contributing life cycle stages are wood and nails extraction and manufacturing (positive value of environmental impact) and end-of-life (avoided impact). This result is driven by two parameters: mass of wood and average distance for transport of wood. Based on the results of the application of the LCI parametric model to the identified products, one parameter-based regression and one multiple non-linear regression allowed to define a correlation between the life cycle impact assessment (LCIA) category indicators considered and the most influencing parameters.

Conclusions

The definition of LCI parametric model in the wooden pallet sector can effectively be used for calculating the environmental impacts of products with different designs, as well as for obtaining a preliminary estimation of the life cycle environmental impacts of new products.  相似文献   

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In many patients who develop epilepsy the disease is short lived and the overall number of seizures small. The role of anticonvulsant drugs in such patients is uncertain. If treatment is merely suppressive and the disease self limiting then treatment may not be necessary in some patients. If, on the other hand, early treatment prevents the subsequent evolution to chronic epilepsy then it is imperative. To resolve this issue it is essential to undertake placebo controlled trials, in which a group of patients with newly diagnosed epilepsy is given active treatment and compared with a similar group given placebo alone.  相似文献   

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Sixty nine patients with chronic duodenal or juxtapyloric ulceration were studied in a prospective double blind randomised trial to compare the efficacy of antacid and placebo at high (30 ml seven times daily) and low (10 ml as required) doses. After four weeks ulcers had healed in 12 out of 18 patients (67%) receiving "low dose" antacid compared with in six out of 17 patients (35%) receiving low dose placebo; ulcers had also healed in six out of 19 patients (32%) receiving "high dose" antacid compared with in two out of 15 patients (13%) receiving high dose placebo. Overall, the effect of antacid was superior to that of placebo in healing ulcers (p less than 0.05) and the effect of low dose treatment was superior to that of high dose treatment (p less than 0.01). There were no significant differences between antacid and placebo at eight weeks. Antacid was better than placebo in relieving pain, but the difference was not significant. Poor compliance and high incidence of diarrhoea made high dose antacid an impractical treatment. Low dose antacid was associated with a significantly better rate of healing than high dose antacid and was far better tolerated. This low dosage of antacid should be considered to be an active treatment in trials of ulcer healing.  相似文献   

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The International Journal of Life Cycle Assessment - The use of life cycle assessment (LCA) as a decision support tool can be hampered by the numerous uncertainties embedded in the calculation. The...  相似文献   

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The International Journal of Life Cycle Assessment - The main goal of this special issue is to further the understanding of how to integrate life cycle sustainability assessment (LCSA) methods and...  相似文献   

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Global Scope and Background  The study was aimed at presenting the methodology of the process eco-indicator, in relation to hard coal mines, and thereby making evaluation of the impact of the mine’s coal extraction process on the environment. The life cycle of a mine is made up of three phases: opening and developing the mine’s deposit, extraction of the mine’s deposit, closing the mine. Methods  The assessment of environmental influence of mining operation of a colliery was executed on a basis of the life cycle analysis, in accordance with the standard series PN-EN 14040. The environmental loads caused by individual unit processes were calculated by means of the aforementioned methodology with division into the basic influence categories: human health, ecosystem quality and natural resources. The obtained values of eco-indicators for the individual unit processes made it possible to compare the unit-process-caused environmental loads. Mean values of the eco-indicators of the individual unit processes were calculated by means of the inventory analysis covering 38 collieries. Next, these indicators were used to compare environmental load values by each similar process in a colliery. A total eco-indicator was calculated for colliery by summing up the eco-indicators of the individual unit processes. The eco-indicators, structured as above, were calculated for the phase of opening out a deposit and for the phase of extraction. Results and Discussion  The model mine in the phase of extraction of a deposit causes a total environmental load which expressed in points of the eco-indicator 99 amounts to 23.9 [MEw]. In the ‘human health’ category losses amount to 8.4 per cent, in the ‘quality of ecosystem’ 0.6 per cent and in the ‘resourses’ category 91 per cent. The greatest losses in all categories are caused by the process of getting body of coal and the next greatest ones are:
–  In the ‘human health’ category-cleaning coal at a preparation plant (250.0 kEw),
–  In the ‘quality of ecosystem’ category-cleaning coal at a preparation plant (25.0 kEw),
–  In the ‘resources’ category-entry driving by means of explosives (745.7 kEw).
Value of the eco-indicator 99 per 1 Mg (tonne) of coal extracted at the model mine amounts to 9.55 Ew. On a basis of this methodology, calculations of the value of the eco-indicator 99 were performed for a real working colliery (extraction of 1.23 million tonnes in 2001). An inventory of characteristic quantities of individual unit processes connected with the extraction of this colliery was prepared. The total environmental load of this mine was 11.14 MEw (in the ‘human health’ category losses amounted to 1.9 per cent, in the ‘quality of ecosystem’ category 0.5 per cent, and in the resources’ category 91.6 per cent). The greatest losses in all categories were caused by the process of getting body of coal which amounted to 10.8 MEw, and next the process of driving a heading by means of heading machine which amounted to 130.9 kEw. The value of the eco-indicator 99 for 1 Mg (tonne) of coal extracted in 2001 at the above-mentioned mine amounts to 9.06 Ew and is lower than the value of the eco-indicator 99 calculated for the model mine. Conclusion  By means of the presented methodology it is possible to calculate environmental loads caused by individual unit processes with division into the basic categories of influence: human health, quality of ecosystem and natural resources. The calculated values of the eco-indicators of the individual unit processes enable to make comparisons of environmental loads and eventual decision making on changes in the ecological policy of a mine. Recommendation and Perspective (Outlook)  The presented LCA methodology can be used to compare the operation of individual mines in the aspect of their influence on the environment. If the data of the same type with regard to unit processes are at disposal, then the mines can be ranked. Based on the LCA’s results, it is possible to make capital decisions connected with modernisation of specific production processes.  相似文献   

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This paper describes the experience with impact assessment of toxic releases in a Substance Flow Analysis (SFA) for PVC in Sweden. For this system, all emissions related to the PVC-chain were inventoried. They have been evaluated making use of the Life Cycle Impact Assessment (LCIA) step from the CMI.-guide, including the new toxicity equivalency factors calculated with the Uniform System for Evaluation of Substances (USES). The application of this method led to the conclusion that I.CA Impact Assessment of toxic releases is still a major bottleneck: the USES-equivalency factors are not to he trusted due to outdated data, inappropriate defaults, etc. in the USES’ substance properties database. Therefore, a second USES-ser of factors was calculated that differed up to factors of 1,000 or more from the old ones. Even these factors probably suffer from unacceptable high structural, in practice not reducible uncertainties. In conclusion, we warn the LCA community not to overestimate the possibility of LCA Impact Assessment to obtain a meaningfull priority setting with regard to toxicity problems. Instead, we propose developing indicator systems for LCIA of toxic releases that genuinely deal with all relevant types of uncertainty: data uncertainty, modelling uncertainty and particularly paradigmatic uncertainty.  相似文献   

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Goal, Scope, and Background  The paper describes the integration of the economic input–output life cycle assessment (EIO-LCA) model and the environmental fate and transport model (CHEMGL) with a risk assessment tool. Utilizing the EIO-LCA, instead of a traditional LCA, enables a rapid, screening-level analysis of an emerging chemical of concern, decabromodiphenyl ether (DecaBDE). The risk assessment in this study is evaluated based on the mass of chemical released, estimated concentrations, exposure, and chemical toxicity. Methods  The relative risk from ten economic sectors identified within the EIO-LCA model, 55 chemicals utilized in those sectors and DecaBDE along with four potential DecaBDE breakdown products, were evaluated for the life cycle stages and exposure pathways. The relative risk (expressed as toluene equivalents) of the different chemicals, sectors, and life cycle stages were compared to assess those representing the greatest overall relative risks to humans (via inhalation and ingestion) and fish. Results  The greatest overall risk to human health resulted from the manufacturing and production stages. For fish, the manufacturing stage represented virtually all of the risk. Of the 56 chemicals evaluated, DecaBDE represented the majority of the total risk to humans. However, DecaBDE posed the least risk compared to its potential breakdown products. Discussion  The risk to humans from ingestion, which represented the greatest risk, from the production, manufacturing, and consumption stages can be controlled and reduced through various safety precautions in the workplace. Additionally, the increasing concentration of DecaBDE in anaerobic compartments represents a threat to humans and fish via the higher risk DecaBDE breakdown products. Conclusions  Overall, the manufacturing and production life cycle stages pose the greatest risk to humans and fish. The sediment compartment received the highest DecaBDE concentration for the production, manufacturing, and consumption stages. This case study demonstrates that the integrated EIO-LCA with risk assessment is suitable for screening-level analysis of emerging chemicals due to rapid life cycle inventory analysis. Recommendations  The production and manufacturing stages allow for greater industry control and government regulation, compared to the consumption stage, because there are fewer point sources. This integrated life cycle methodology may allow chemical designers to evaluate each stage and assess areas where risks can be minimized.  相似文献   

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