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1.

Purpose

To contribute to the upcoming United Nations Conference on Sustainable Development (Rio+20) in 2012 by introducing a life cycle sustainability assessment (LCSA) and showing how it can play a crucial role in moving towards sustainable consumption and production. The publication, titled Towards a Life Cycle Sustainability Assessment, and published by the UNEP/SETAC Life Cycle Initiative aims to show how three life cycle techniques—(environmental) LCA, S-LCA and LCC—can be combined as part of an over-arching LCSA.

Methods

The method was demonstrated by evaluating the characteristics of each phase for each life cycle technique. In defining the goal and scope of an LCSA, for example, different aspects should be taken into account to establish the aim of the study as well as the functional unit, system boundaries, impact category and allocation. Then, the data to be collected for the life cycle sustainability inventory can be either in a unit process or on an organisational level. They can also be quantitative or qualitative. Life cycle sustainability impact assessment should consider the relevance of the impacts as well as the perspective of stakeholders. The interpretation should not add up the results, but rather evaluate them jointly. In order to clarify the approach, a case study is presented to evaluate three types of marble according to the proposed method.

Results and discussion

The authors have identified that while LCSA is feasible, following areas need more development: data production and acquisition, methodological development, discussion about LCSA criteria (e.g. cutoff rules), definitions and formats of communication and dissemination of LCSA results and the expansion of research and applications combining (environmental) LCA, LCC and S-LCA. The authors also indicate that it is necessary to develop more examples and cases to improve user capacity to analyse the larger picture and therefore address the three dimensions or pillars of sustainability in a systematic way. Software and database providers are called for in order to facilitate user-friendly and accessible tools to promote LCSAs.

Conclusions

The application demonstrated that, although methodological improvements are still needed, important steps towards an overarching sustainability assessment have been accomplished. LCSA is possible and should be pursued; however, more efforts should be made to improve the technique and facilitate the studies in order to contribute to a greener economy.  相似文献   
2.
3.
Purpose

A review of LCA process datasets is an important element of quality assurance for databases and for other systems to provide LCA datasets. Somewhat surprisingly, a broadly accepted and applicable set of criteria for a review of LCA process datasets was lacking so far. Different LCA databases and frameworks are proposing and using different criteria for reviewing datasets. To close this gap, a set of criteria for reviewing LCA dataset has been developed within the Life Cycle Initiative.

Methods

Previous contributions to LCA dataset review have been analysed for a start, from ISO and various LCA databases. To avoid somewhat arbitrary review criteria, four basic rules are proposed which are to be fulfilled by any dataset. Further, concepts for assessing representativeness and relevance are introduced into the criteria set from established practices in statistics and materiality. To better structure the criteria and to ease their application, they are grouped into clusters. A first version of the developed review criteria was presented in two workshops with database providers and users on different levels of experience, and draft versions of the criteria were shared within the initiative. The current version of the criteria reflects feedback received from various stakeholders and has been applied and tested in a review for newly developed datasets in Brazil, Malaysia and Thailand.

Results and discussion

Overall, 14 criteria are proposed, which are organised in clusters. The clusters are goal, model, value, relevance and procedure. For several criteria, a more science-based definition and evaluation is proposed in comparison to ‘traditional’ LCA. While most of the criteria depend on the goal and scope of dataset development, a core set of criteria are seen as essential and independent from specific LCA modelling. For all the criteria, value scales are developed, typically using an ordinal scale, following the pedigree approach.

Conclusions

Review criteria for LCI datasets are now defined based on a stringent approach. They aim to be globally acceptable, considering also database interoperability and database management aspects, as well as feedback received from various stakeholders, and thus close an important gap in LCA dataset quality assurance. The criteria take many elements of already existing criteria but are the first to fully reflect the implications of the ISO data quality definition, and add new concepts for representativeness and relevance with the idea to better reflect scientific practice outside of the LCA domain. A first application in a review showed to be feasible, with a level of effort similar to applying other review criteria. Aspects not addressed yet are the review procedure and the mutual recognition of dataset reviews, and their application for a very high number of datasets.

  相似文献   
4.
Wilson disease is caused by accumulation of Cu(2+) in cells, which results in liver cirrhosis and, occasionally, anemia. Here, we show that Cu(2+) triggers hepatocyte apoptosis through activation of acid sphingomyelinase (Asm) and release of ceramide. Genetic deficiency or pharmacological inhibition of Asm prevented Cu(2+)-induced hepatocyte apoptosis and protected rats, genetically prone to develop Wilson disease, from acute hepatocyte death, liver failure and early death. Cu(2+) induced the secretion of activated Asm from leukocytes, leading to ceramide release in and phosphatidylserine exposure on erythrocytes, events also prevented by inhibition of Asm. Phosphatidylserine exposure resulted in immediate clearance of affected erythrocytes from the blood in mice. Accordingly, individuals with Wilson disease showed elevated plasma levels of Asm, and displayed a constitutive increase of ceramide- and phosphatidylserine-positive erythrocytes. Our data suggest a previously unidentified mechanism for liver cirrhosis and anemia in Wilson disease.  相似文献   
5.
Chronic obstructive pulmonary disease (COPD) is one of the most important causes of morbidity and mortality in the world. The disease is often aggravated by periods of increased symptoms requiring medical attention. Among the possible triggers for these exacerbations, meteorological factors are under consideration. The objective of this study was to assess the influence of various meteorological factors on the health status of patients with COPD. For this purpose, the daily number of ambulatory care visits due to COPD was analysed in Bavaria, Germany, for the years 2006 and 2007. The meteorological factors were provided by the model at the European Centre for Medium Range Weather Forecast (ECMWF). For the multivariate analysis, a generalised linear model was used. In Bavaria, an increase of 1% of daily consultations (about 103 visits per day) was found to be associated with a change of 0.72?K temperature, 209.55 of log air surface pressure in Pa, and a decrease of 1% of daily consultations with 1,453,763 Ws m2 of solar radiation. There also seem to be regional differences between north and south Bavaria; for instance, the effect of wind speed and specific humidity with a lag of 1?day were only significant in the north. This study could contribute to a tool for the prevention of exacerbations. It also serves as a model for the further evaluation of the impact of meteorological factors on health, and could easily be applied to other diseases or other regions.  相似文献   
6.
The fluorescence depolarization of 1,6-diphenyl-hexatriene was used to study the dynamic properties of the hydrophobic regions of the lipid envelopes of ortho- and paramyxoviruses as well as of the Rous sarcoma virus and of the membrane lipids of susceptible and nonsusceptible cells.The systems investigated where active and inactive influenza viruses, and NDV virus acting on chick embryo fibroblasts and Rous sarcoma virus acting on susceptible (C/E) and nonsusceptible (C/B) chicken-cell.Polarization degrees and mean rotational correlation times of DPH embedded in viral lipids were significantly higher than those of DPH in the cell membranes, due to a higher rigidity of the virus envelopes. When suspensions of labelled viruses and unlabelled cells or unlabelled viruses and labelled cells were mixed, a characteristic change of the fluorescence polarization degrees with time was observed. This behaviour was ascribed to a label transfer from virus to cell membranes or vice versa.While the rate constants of label transfer from virus to cells and cells to virus were about the same for the penetrating viruses the rate constants of label release from inactive virus to cells were much larger than for the migration in the opposite direction.  相似文献   
7.
A nanocompartment system composed of an ABA triblock copolymer, where A is poly(dimethylsiloxane) and B is poly(2-methyloxazoline), has been developed for selective recovery and detection of DNA. Translocation of TAMRA-labeled complementary primers into the nanocompartment system has been achieved through two deletion mutants (FhuA Delta1-129; FhuA Delta1-160) of the channel protein FhuA. Translocation was monitored by fluorescence resonance energy transfer through hybridization of the TAMRA-labeled primer to the complementary sequence of a nanophosphor-DNA-conjugate, which reduces its half-life (FhuA Delta1-129, 16.0% reduced; FhuA Delta1-160, 39.0% reduced).  相似文献   
8.
Hsp90 is a ubiquitous molecular chaperone that plays a key role in the malignant development of hormone-dependent pathologies such as cancer. An important role for Hsp90 is to facilitate the stable binding of steroid hormones to their respective receptors enabling the ligand-based signal to be carried to the nucleus and ultimately resulting in the up-regulation of gene expression. Along with Hsp90, this dynamic and transient process also involves the recruitment of additional proteins and co-chaperones that add further stability to the mature receptor–chaperone complex. In the work presented here, we describe four new protocols for the bacterial over-expression and column chromatographic purification of the human p23, FKBP52, HOP and SGTα proteins. Each of these proteins plays a distinct role in the steroid hormone receptor regulatory cycle. Affinity, ion-exchange and size-exclusion techniques were used to produce target yields greater than 50 mg/L of cultured media, with each purified sample reaching near absolute sample homogeneity. These results reveal a reliable system for the production of p23, FKBP52, HOP and SGTα substrate proteins for use in the investigation of the Hsp90-associated protein interactions of the steroid hormone receptor cycle.  相似文献   
9.
Previous studies revealed that one species of methanogenic archaea, Methanocaldococcus jannaschii, is polyploid, while a second species, Methanothermobacter thermoautotrophicus, is diploid. To further investigate the distribution of ploidy in methanogenic archaea, species of two additional genera-Methanosarcina acetivorans and Methanococcus maripaludis-were investigated. M. acetivorans was found to be polyploid during fast growth (t(D) = 6 h; 17 genome copies) and oligoploid during slow growth (doubling time = 49 h; 3 genome copies). M. maripaludis has the highest ploidy level found for any archaeal species, with up to 55 genome copies in exponential phase and ca. 30 in stationary phase. A compilation of archaeal species with quantified ploidy levels reveals a clear dichotomy between Euryarchaeota and Crenarchaeota: none of seven euryarchaeal species of six genera is monoploid (haploid), while, in contrast, all six crenarchaeal species of four genera are monoploid, indicating significant genetic differences between these two kingdoms. Polyploidy in asexual species should lead to accumulation of inactivating mutations until the number of intact chromosomes per cell drops to zero (called "Muller's ratchet"). A mechanism to equalize the genome copies, such as gene conversion, would counteract this phenomenon. Making use of a previously constructed heterozygous mutant strain of the polyploid M. maripaludis we could show that in the absence of selection very fast equalization of genomes in M. maripaludis took place probably via a gene conversion mechanism. In addition, it was shown that the velocity of this phenomenon is inversely correlated to the strength of selection.  相似文献   
10.
Gold nanoparticles (GNPs) enhance the damaging absorbance effects of high-energy photons in radiation therapy by increasing the emission of Auger-photoelectrons in the nm-μm range. It has been shown that the incorporation of GNPs has a significant effect on radiosensitivity of cells and their dose-dependent clonogenic survival. One major characteristic of GNPs is also their diameter-dependent cellular uptake and retention. In this article, we show by means of an established embodiment of localization microscopy, spectral position determination microscopy (SPDM), that imaging with nanometer resolution and systematic counting of GNPs becomes feasible, because optical absorption and plasmon resonance effects result in optical blinking of GNPs at a size-dependent wavelength. To quantify cellular uptake and retention or release, SPDM with GNPs that have diameters of 10 and 25 nm was performed after 2 h and after 18 h. The uptake of the GNPs in HeLa cells was either achieved via incubation or transfection via DNA labeling. On average, the uptake by incubation after 2 h was approximately double for 10 nm GNPs as compared to 25 nm GNPs. In contrast, the uptake of 25 nm GNPs by transfection was approximately four times higher after 2 h. The spectral characteristics of the fluorescence of the GNPs seem to be environment-dependent. In contrast to fluorescent dyes that show blinking characteristics due to reversible photobleaching, the blinking of GNPs seems to be stable for long periods of time, and this facilitates their use as an appropriate dye analog for SPDM imaging.  相似文献   
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