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101.
Hans-J?rg?AlthausEmail author Mischa?ClassenEmail author 《The International Journal of Life Cycle Assessment》2005,10(1):43-49
Goal, Scope and Background The ecoinvent database provides harmonised generic life cycle inventories for metal production and processing. They can be used as background data for different LCA applications. The goal of this paper is to provide an overview of the metals inventoried in ecoinvent. Beside, some methodological background information is given. The focus lies on a new methodology developed to inventorying joint resources. The implementation is shown in a case study of the production of primary copper on a global average. The respective process is assessed with Eco-indicator 99 (H,A) to identify dominant impacts within the production chain.Methods In ecoinvent, a coupled production is inventoried in multi output unit processes. For database calculation, an allocation by economic revenue is applied. Elementary flows for resources, especially joint resources, include information on type and quality of the resources.Results and Conclusion With the presented method, the extraction of resources can be valuated based on the cost of restoration or the change in the future impact due to the extraction of a specific resource. The case study indicates, for copper / molybdenum production, that the mineral extraction is of minor importance compared to the metallurgical step according to the LCIA results. Air emissions of heavy metals are identified as main impacts. Also, the resource depletion shows a notable impact. The environmental impacts of metals from sulphidic ores, however, are underestimated by neglecting emissions from tailings for lack of reliable data.Recommendation and Perspective Impact assessment methods will have to be updated to account for different grades of ore. The ecoinvent database should be enlarged by more inventories of technically important metals and alloys, e.g. by gold, silver, solders, etc. for the electronics industry and by specific steel and aluminium alloys. Reliable composition data of sulphidic tailings and transfer coefficients for their disposal considering Acidic Rock Drainage (ARD) are to be developed as well. 相似文献
102.
Michael?SpielmannEmail author Roland?ScholzEmail author Olaf?Tietje Peter de?Haan 《The International Journal of Life Cycle Assessment》2005,10(5):325-335
Background Tools and methods able to cope with uncertainties are essential for improving the credibility of Life Cycle Assessment (LCA)
as a decision support tool. Previous approaches have focussed predominately upon data quality.
Objective and Scope. An epistemological approach is presented conceptualising uncertainties in a comparative, prospective, attributional
LCA. This is achieved by considering a set of cornerstone scenarios representing future developments of an entire Life Cycle
Inventory (LCI) product system. We illustrate the method using a comparison of future transport systems.
Method Scenario modelling is organized by means of Formative Scenario Analysis (FSA), which provides a set of possible and consistent
scenarios of those unit processes of an LCI product system which are time dependent and of environmental importance. Scenarios
are combinations of levels of socio-economic or technological impact variables. Two core elements of FSA are applied in LCI
scenario modelling. So-called impact matrix analysis is applied to determine the relationship between unit process specific
socio-economic variables and technology variables. Consistency Analysis is employed to integrate unit process scenarios, based
on pair-wise ratings of the consistency of the levels of socio-economic impact variables of all unit processes. Two software
applications are employed which are available from the authors.
Results and Discussion The study reveals that each possible level or development of a technology variable is best conceived of as the impact of
a specific socio-economic (sub-) scenario. This allows for linking possible future technology options within the socio-economic
context of the future development of various background processes. In an illustrative case study, the climate change scores
and nitrogen dioxide scores per seat kilometre for six technology options of regional rail transport are compared. Similar
scores are calculated for a future bus alternative and an average Swiss car.
The scenarios are deliberately chosen to maximise diversity. That is, they represent the entire range of future possible developments.
Reference data and the unit process structure are taken from the Swiss LCA database 'ecoinvent 2000'. The results reveal that
rail transport remains the best option for future regional transport in Switzerland. In all four assessed scenarios, four
technology options of future rail transport perform considerably better than regional bus transport and car transport.
Conclusions and Recommendations. The case study demonstrates the general feasibility of the developed approach for attributional prospective
LCA. It allows for a focussed and in-depth analysis of the future development of each single unit process, while still accounting
for the requirements of the final scenario integration. Due to its high transparency, the procedure supports the validation
of LCI results. Furthermore, it is well-suited for incorporation into participatory methods so as to increase their credibility.
Outlook and Future Work. Thus far, the proposed approach is only applied on a vehicle level not taking into account alterations in
demand and use of different transport modes. Future projects will enhance the approach by tackling uncertainties in technology
assessment of future transport systems. For instance, environmental interventions involving future maglev technology will
be assessed so as to account for induced traffic generated by the introduction of a new transport system. 相似文献
103.
Franziska?BremEmail author Ann?M.?Hirt Christian?Simon Heinz-Gregor?Wieser Jon?Dobson 《Biometals》2005,18(2):191-197
Excess iron accumulation in the brain has been shown to be related to a variety of neurodegenerative diseases. However, identification and characterization of iron compounds in human tissue is difficult because concentrations are very low. For the first time, a combination of low temperature magnetic methods was used to characterize iron compounds in tumour tissue from patients with mesial temporal lobe epilepsy (MTLE). Induced magnetization as a function of temperature was measured between 2 and 140 K after cooling in zero-field and after cooling in a 50 mT field. These curves reveal an average blocking temperature for ferritin of 10 K and an anomaly due to magnetite at 48 K. Hysteresis measurements at 5 K show a high coercivity phase that is unsaturated at 7 T, which is typical for ferritin. Magnetite concentration was determined from the saturation remanent magnetization at 77 K. Hysteresis measurements at various temperatures were used to examine the magnetic blocking of magnetite and ferritin. Our results demonstrate that low temperature magnetic measurements provide a useful and sensitive tool for the characterisation of magnetic iron compounds in human tissue.Published online: March 2005 相似文献
104.
Damage of leaf spot, caused by Mycosphaerella fragariae and gray mold also called Botrytis fruit rot, caused by Botrytis cinerea, average fruit weight and yield were evaluated with regard to cultural methods over 2years. Leaf spot damage decreased significantly by around 90% due to leaf sanitation (removal of dead and leaf spot infected leaves in early spring) and by 50% due to plantation in a one-row-system instead of a two-row-system. When all leaves including the healthy green ones were removed in early spring, average fruit weight decreased significantly by 10%. Fruit sanitation – the third treatment – did not influence any of the measured parameters. Neither leaf sanitation nor fruit sanitation (removal of damaged fruits during harvest) reduced B. cinerea damage significant. Only the combination of a one-row-system, leaf sanitation and fruit sanitation almost halved (not significantly) B. cinerea damage in the first crop year compared to a two-row-system without leaf and fruit sanitation. B. cinerea damage correlated significantly and positively with the biomass of plants by R2= 0.47. According to this study and the cited literature it is suggested for humid Central European conditions to apply a one-row-system combined with leaf sanitation in early spring and fruit sanitation during harvest if fruit density is high, to reduce the risk of damages in larger dimension caused by M. fragariae and B. cinerea. 相似文献
105.
Background
Whole-genome sequencing projects are rapidly producing an enormous number of new sequences. Consequently almost every family of proteins now contains hundreds of members. It has thus become necessary to develop tools, which classify protein sequences automatically and also quickly and reliably. The difficulty of this task is intimately linked to the mechanism by which protein sequences diverge, i.e. by simultaneous residue substitutions, insertions and/or deletions and whole domain reorganisations (duplications/swapping/fusion). 相似文献106.
Alain?Sewer Nicodème?Paul Pablo?Landgraf Alexei?Aravin Sébastien?Pfeffer Michael?J?Brownstein Thomas?Tuschl Erik?van Nimwegen Mihaela?ZavolanEmail author 《BMC bioinformatics》2005,6(1):267
Background
MicroRNAs (miRNAs) are endogenous 21 to 23-nucleotide RNA molecules that regulate protein-coding gene expression in plants and animals via the RNA interference pathway. Hundreds of them have been identified in the last five years and very recent works indicate that their total number is still larger. Therefore miRNAs gene discovery remains an important aspect of understanding this new and still widely unknown regulation mechanism. Bioinformatics approaches have proved to be very useful toward this goal by guiding the experimental investigations. 相似文献107.
Olivier?BraissantEmail author Hugues?Henry Anne-Marie?Villard Oliver?Speer Theo?Wallimann Claude?Bachmann 《BMC developmental biology》2005,5(1):9
Background
Creatine (Cr) is synthesized by a two-step mechanism involving arginine:glycine amidinotransferase (AGAT) and guanidinoacetate methyltransferase (GAMT), and is taken up by cells through a specific Cr transporter, CT1. Recently, genetic defects of this pathway have been described, that lead to Cr deficiency, neurological symptoms in early infancy and severe neurodevelopmental delay. To investigate the involvement of Cr synthesis and uptake pathways during embryonic development, we determined the spatiotemporal expression of AGAT, GAMT and CT1 during the rat embryogenesis, at the mRNA and protein level. 相似文献108.
Lionel?Guy Dimitri?Karamata Philippe?Moreillon Claude-Alain?H?RotenEmail author 《BMC microbiology》2005,5(1):60
Background
Analysis of the first reported complete genome sequence ofBifidobacterium longumNCC2705, an actinobacterium colonizing the gastrointestinal tract, uncovered its proteomic relatedness toStreptomyces coelicolorandMycobacterium tuberculosis. However, a rapid scrutiny by genometric methods revealed a genome organization totally different from all so far sequenced high-GC Gram-positive chromosomes. 相似文献109.
110.