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Gjalt Huppes Arjan de Koning Sangwon Suh Reinout Heijungs Lauran van Oers Per Nielsen Jeroen B. Guine 《Journal of Industrial Ecology》2006,10(3):129-146
For developing product policy, insight into the environmental effects of products is required. But available life-cycle assessment studies (LCAs) are hardly comparable between different products and do not cover total consumption. Input-output analysis with environmental extensions (EEIOA) of full consumption is not available for the European Union. Available country studies have a low sector resolution and a limited number of environmental extensions. This study fills the gap between detailed LCA and low-resolution EEIOA, specifying the environmental effects of household consumption in the European Union, discerning nearly 500 sectors, while specifying a large number of environmental extensions. Added to the production sectors are a number of consumption activities with direct emissions, such as automobile driving, cooking and heating, and a number of postconsumer waste management sectors. The data for Europe have been constructed by using the sparse available and coarse economic and environmental data on European countries and adding technological detail mainly based on data from the United States.
A small number of products score high on environmental impact per Euro and also have a substantial share of overall consumer expenditure. Several meat and dairy products, household heating, and car driving thus have a large share of the total environmental impact. Due to their sales volume, however, products with a medium or low environmental score per Euro may also have a substantial impact. This is the case with bars and restaurants, clothing, residential construction, and even a service such as telecommunications. The limitations in real European data made heroic assumptions necessary to operationalize the model. One conclusion, therefore, is that provision of data in Europe urgently needs to be improved, at least to the level of sector detail currently available for the United States and Japan. 相似文献
A small number of products score high on environmental impact per Euro and also have a substantial share of overall consumer expenditure. Several meat and dairy products, household heating, and car driving thus have a large share of the total environmental impact. Due to their sales volume, however, products with a medium or low environmental score per Euro may also have a substantial impact. This is the case with bars and restaurants, clothing, residential construction, and even a service such as telecommunications. The limitations in real European data made heroic assumptions necessary to operationalize the model. One conclusion, therefore, is that provision of data in Europe urgently needs to be improved, at least to the level of sector detail currently available for the United States and Japan. 相似文献
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Reinout Heijungs Sangwon Suh René Kleijn 《The International Journal of Life Cycle Assessment》2005,10(2):103-112
Goal, Scope and Background To strengthen the evaluative power of LCA, life cycle interpretation should be further developed. A previous contribution (Heijungs & Kleijn 2001) elaborated five examples of concrete methods within the subset of numerical approaches towards interpretation. These methods were: contribution analysis, perturbation analysis, uncertainty analysis, comparative analysis, and discernibility analysis. Developments in software have enabled the possibility to apply the five example methods to explore the much-used Ecoinvent”96 database.Discussion of Methods The numerical approaches implemented in this study include contribution analysis, perturbation analysis, uncertainty analysis, comparative analysis, discernibility analysis and the newly developed key issue analysis. The data used comes from a very large process database: Ecoinvent’96, containing 1163 processes, 1181 economic flows and 571 environmental flows. Conclusions Results are twofold: they serve as a benchmark to the usefulness and feasibility of these numerical approaches, and they shed light on the question of stability and structure in an often-used large system of interconnected processes. Most of the approaches perform quite well: computation time on a moderate PC is between a few seconds a few minutes. Only Monte Carlo analyses may require much longer, but even then it appears that most questions can be answered within a few hours. Moreover, analytical expressions for error propagation are much faster than Monte Carlo analyses, while giving almost identical results. Despite the fact that many processes are connected to each other, leading to the possibility of a very unstable system and very sensitive coefficients, the overall results show that most results are not extremely uncertain. There are, however, some exceptions to this positive message. 相似文献
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Jeroen B. Guinée Reinout Heijungs Ester van der Voet 《The International Journal of Life Cycle Assessment》2009,14(4):328-339
Background, aim, and scope The expectations with respect to biomass as a resource for sustainable energy are sky-high. Many industrialized countries
have adopted ambitious policy targets and have introduced financial measures to stimulate the production or use of bioenergy.
Meanwhile, the side-effects and associated risks have been pointed out as well. To be able to make a well-informed decision,
the Dutch government has expressed the intention to include sustainability criteria into relevant policy instruments.
Main features Among other criteria, it has been proposed to calculate a so-called life-cycle-based greenhouse gas (GHG) indicator, which
expresses the reduction of GHG emissions of a bio-based fuel chain in comparison with a fossil-based fuel chain. Life-cycle-based
biofuel studies persistently have problems with the handling of biogenic carbon balances and with the treatment of coproducts
and recycling. In life-cycle assessments (LCAs) of agricultural products, a distinction between “negative” and “positive”
emissions may be relevant. In particular, carbon dioxide, as a naturally occurring compound or an anthropogenic emission,
takes part in the so-called geochemical carbon cycle. The most appropriate way to treat carbon cycles is to view them as genuine
cycles and, thus, at the systems level, subtract the fixation of CO2 during tree growth from the CO2 emitted during waste treatment of discarded wood and to quantify the CH4 emitted. In solving the multifunctionality problem, two steps may be distinguished. The first concerns the modeling of the
product system studied in the inventory analysis. In this step, system boundaries are set, processes are described, and process
flows are quantified. Multifunctionality problems can be identified and the model of the product system is drafted. The second
step concerns solving the remaining multifunctionality problems. For this step, various ways of solving the multifunctionality
problem have been proposed and applied, on the basis of mass, energy, economic value, avoided burdens, etc. As the GHG indicator
may constitute the basis for granting subsidies to stimulate the use of bioenergy, for example, and as the method for the
GHG indicator provides no guidelines on the handling of biogenic CO2 and guidelines for solving multifunctionality problems such as with coproducts and recycling that leave room for various
choices, this study analyzed whether the current GHG indicator provides results that are a robust basis for granting such
subsidies.
Results For the robustness check, a hypothetical case study on wood residue-based electricity was set up in order to illustrate what
the effects of different solutions and choices for the two steps mentioned may be. The case dealt with the production of wood
pellets (residues of the wood industry) that are cofired in a coal-fired power plant. The functional unit is 1 kWh of electricity.
Three possibilities for the places of the multifunctional process, two possibilities for whether or not to include biogenic
CO2, and four possibilities for the allocation method were distinguished and calculated. Varying the options for these three
choices in this way appears to have a huge effect on the GHG indicator, while no clear pattern seems to emerge.
Discussion The results found for this hypothetical case indicate that there are several methodological choices that have not sufficiently
been fixed by the presently available standards and guidelines for LCA and GHG assessment of bioenergy systems. In particular,
we have focused on issues related to biogenic CO2 and allocation, two issues that play a prominent role in the assessment of bioenergy systems. Moreover, we have demonstrated
with a small hypothetical case study that these are not only issues that might theoretically show up, but that they play a
decisive role in practice.
Conclusions The present (Dutch) GHG indicator lacks robustness, which will raise problems for providing a sound basis for granting subsidies.
This situation can, however, be improved by reducing the freedom of choices for the handling of biogenic CO2 and allocation to an absolute minimum.
Recommendations and perspectives Even then, however, differences could appear due to different definitions, data sources, and method interpretations. It thus
appears that two kinds of guidance are needed: (1) the LCA methodology itself should be expanded with guidelines for those
issues that follow from science, logic, or consensus; (2) in the policy regulation that demands LCA to be the basis of the
decision, additional guidelines should be specified that perhaps do not (yet) have the status of being scientifically proven
or generally agreed upon, but that serve as a set of temporary extra guidelines.
相似文献
Jeroen B. GuinéeEmail: |
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Merrin Rutherford Bachti Alisjahbana Winni Maharani Hedy Sampurno Reinout van Crevel Philip C. Hill 《PloS one》2010,5(8)
Background
As part of a formal evaluation of the Quantiferon-Gold in-tube assay (QFT-IT) for latent TB infection we compared its sensitivity to the tuberculin skin test (TST) in confirmed adult TB cases in Indonesia. Smear-positive TB disease was used as a proxy gold standard for latent TB infection.Methods and Findings
We compared the sensitivity of QFT-IT and TST in 98 sputum smear and chest x-ray positive TB cases and investigated risk factors for negative and discordant results in both tests. Both tests showed high sensitivity; (QFT-IT; 88.7%: TST; 94.9%), not significantly different from each other (p value 0.11). Very high sensitivity was seen when tests were combined (98.9%). There were no variables significantly associated with discordant results or with a negative TST. For QFT-IT which particular staff member collected blood was significantly associated with test positivity (p value 0.01). Study limitations include small sample size and lack of culture confirmation or HIV test results.Conclusions
The QFT-IT has similar sensitivity in Indonesian TB cases as in other locations. However, QFT-IT, like the TST cannot distinguish active TB disease from LTBI. In countries such as Indonesia, with high background rates of LTBI, test specificity for TB disease will likely be low. While our study was not designed to evaluate the QFT-IT in the diagnosis of active TB disease in TB suspects, the data suggest that a combination of TST and QFT-IT may prove useful for ruling out TB disease. Further research is required to explore the clinical role of QFT-IT in combination with other TB diagnostic tests. 相似文献25.
Priya A. Debisarun Katharina L. Gssling Ozlem Bulut Gizem Kilic Martijn Zoodsma Zhaoli Liu Marina Oldenburg Nadine Rüchel Bowen Zhang Cheng-Jian Xu Patrick Struycken Valerie A. C. M. Koeken Jorge Domínguez-Andrs Simone J. C. F. M. Moorlag Esther Taks Philipp N. Ostermann Lisa Müller Heiner Schaal Ortwin Adams Arndt Borkhardt Jaap ten Oever Reinout van Crevel Yang Li Mihai G. Netea 《PLoS pathogens》2021,17(10)
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José A Navarro Christian E Lowe Reinout Amons Takamitsu Kohzuma Gerard W Canters Miguel A De la Rosa Marcellus Ubbink Manuel Hervás 《European journal of biochemistry》2004,271(16):3449-3456
Plastocyanin (Pc) is a soluble copper protein that transfers electrons from cytochrome b(6)f to photosystem I (PSI), two protein complexes that are localized in the thylakoid membranes in chloroplasts. The surface electrostatic potential distribution of Pc plays a key role in complex formation with the membrane-bound partners. It is practically identical for Pcs from plants and green algae, but is quite different for Pc from ferns. Here we report on a laser flash kinetic analysis of PSI reduction by Pc from various eukaryotic and prokaryotic organisms. The reaction of fern Pc with fern PSI fits a two-step kinetic model, consisting of complex formation and electron transfer, whereas other plant systems exhibit a mechanism that requires an additional intracomplex rearrangement step. The fern Pc interacts inefficiently with spinach PSI, showing no detectable complex formation. This can be explained by assuming that the unusual surface charge distribution of fern Pc impairs the interaction. Fern PSI behaves in a similar way as spinach PSI in reaction with other Pcs. The reactivity of fern Pc towards several soluble c-type cytochromes, including cytochrome f, has been analysed by flavin-photosensitized laser flash photolysis, demonstrating that the specific surface motifs for the interaction with cytochrome f are conserved in fern Pc. 相似文献
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