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1.

Introduction

Data sharing is being increasingly required by journals and has been heralded as a solution to the ‘replication crisis’.

Objectives

(i) Review data sharing policies of journals publishing the most metabolomics papers associated with open data and (ii) compare these journals’ policies to those that publish the most metabolomics papers.

Methods

A PubMed search was used to identify metabolomics papers. Metabolomics data repositories were manually searched for linked publications.

Results

Journals that support data sharing are not necessarily those with the most papers associated to open metabolomics data.

Conclusion

Further efforts are required to improve data sharing in metabolomics.
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2.

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http://dx.doi.org/10.1065/lca2006.04.009

Goal, Scope and Method

logy. This paper describes a case study carried out as part of a wider programme to provide support for environmental decision-making in the highway maintenance programme of a local government body: Surrey County Council (SCC). UK local authorities are required to demonstrate that sustainable development principles are addressed in service provision, by improving environmental, economic or social wellbeing and improving public consultation. A methodological approach was developed to meet these requirements by using life cycle assessment (LCA) and multi-criteria decision analysis (MCDA) through the process of decision conferencing.

Results

In projects requiring strategic decisions, difficulties arise in identifying relevant sustainable development criteria and in evaluating maintenance options against these criteria where the context for decision-making is complex and characterised by uncertainty, where multiple public policy objectives compete and a number of decision-makers and key players are affected by the outcome. Clearly, a structured process is needed to engage such stakeholders in the decision process, utilising quantitative and qualitative information. The approach described proved to be capable of fulfilling these requirements.

Conclusions

and Recommendations. The approach of combining LCA with MCDA through decision conferencing is capable of further development to support other strategic decision-making activities. However, this illustrative case study has revealed a need for methodological developments in LCA for local, project-level decisions.
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3.

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DOI: http://dx.doi.org/10.1065/lca2006.04.018

Goal, Scope and Background

Life cycle assessment has emerged into a useful tool to assess and potentially reduce the environmental impacts per functional unit. This has contributed to increase eco-efficiency but not necessarily to decrease absolute pollution per capita. The number of functional units is increasing and new functions add to the impacts of consumption. Despite the attempts to use different levels of definitions for the functional unit and applying LCA in the field of lifestyle studies there has been little success to grasp the consumption side of sustainable production and consumption. This contribution aims to tackle the consumption side by at least two extensions: the function of products, services, and activities is assessed with a multi-attribute need function and the propensity to cause both psychological and physical rebound effects are considered in the design phase.

Methods

We develop a checklist approach with an evaluation and assessment table. The elements of the checklist are rooted in a number of independent fields of science: needs matrix, happiness enhancing factors, a number of limiting factors that can cause rebound effects, and streamlined LCA.

Results and Conclusion

For illustration purposes we comparatively evaluate gardening, having a dog, a weekend house, and starting yoga classes and show that the new analysis framework is able to make transparent and operable the inclusion of a number of additional factors that remained so far implicit or neglected. The additional factors considered can be grouped into factors that may cause rebound effects through psychological or physical mechanisms. The assessment table combines the degree of satisfying needs and enhancing happiness in a psychological rebound score. The physical rebound score considers six factors that may constrain consumption: Costs, time, space, other scarce resources, information, and skills. This allows predicting the potential for rebound effects that would increase total impacts from consumption. In addition, it gives also a handle on how to use the knowledge on rebound effects to not only reduce the impacts of the product or activity at hand but also reducing other consumption that in turn might have adverse impacts.

Recommendation and Perspective

Many assumptions in selecting and quantifying the additional factors and the final assessment procedure remain conceptual and therefore provisional. This contribution opens new avenues of investigations that need both further refinements of the theories and empirical evidence. Consumerism and materialism has undermined much of the success stories of improved eco-efficiency and LCA. We suggest using some of the very same psychological and physical mechanisms to foster sustainable consumption.
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4.

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DOI: http://dx.doi.org/10.1065/lca2006.04.008

Goal, Scope and Background

CML has contributed to the development of life cycle decision support tools, particularly Substance / Material Flow Analysis (SFA respectively MFA) and Life Cycle Assessment (LCA). Ever since these tools emerged there have been discussions on how these tools relate to each other, and how they relate to more traditional tools. Remarkably little, however, has been published on these relationships from an empirical side: which combinations of tools have actually been used, and what is the added value of combining tools in practical case studies. In this paper, we report on CML's experience in this field by presenting a number of case studies with their related research questions, for which different tools were deployed.

Methods

Three case studies are discussed: 1) Waste water treatment: various options for waste water treatment have been assessed on their eco-efficiency, using SFA to comment on the influence of these options on the flows of certain substances in the water system of a geographical area and a combination of LCA and life cycle costing (LCC) to assess the life-cycle impacts and costs of these options; 2) Prioritization of environmental policy measures: A methodology has been developed to prioritize environmental policy measures and investments within companies based on both the environmental impacts and the costs of these measures; and 3) Environmental weighting of materials: to add an environmental dimension to standard MFA accounts, materials were weighted with cradle-to-grave impact factors based on LCA data and impact assessment factors.

Results and Discussion

For each of these cases, the research questions at stake, the tools applied, the results and the added value, limitations and problems of combining the tools are reported.

Conclusions

and Perspective. Based on these experiences, it is concluded that using several tools to address a complicated problem is not only a theoretical proposal, but also something that has been applied successfully in a variety of practical situations. Furthermore, using several tools in combination does not necessarily lead to an increased information supply to decisionmakers. Instead, it may contribute to the comprehensibility and ease of interpretation of the information that would have been provided by using a single tool. Finally, it is concluded that there is not one generally valid protocol for which tools to use for which question. The essential idea of using a combination of tools is exactly the fact that research questions are not simple by nature and cannot be generalized into protocols.
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5.

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DOI: http://dx.doi.org/10.1065/lca2006.04.016

Goal, Scope and Background

Although both cost-benefit analysis (CBA) and life cycle assessment (LCA) have developed from engineering practice, and have the same objective of a holistic ex-ante assessment of human activities, the techniques have until recently developed in relative isolation. This has resulted in a situation where much can be gained from an integration of the strong aspects of each technique. Such integration is now being prompted by the more widespread use of both CBA and LCA on the global arena, where also the issues of social responsibility are now in focus. Increasing availability of data on both biophysical and social impacts now allow the development of a truly holistic, quantitative environmental assessment technique that integrates economic, biophysical and social impact pathways in a structured and consistent way. The concept of impact pathways, linking biophysical and economic inventory results via midpoint impact indicators to final damage indicators, is well described in the LCA and CBA literature. Therefore, this paper places specific emphasis on how social aspects can be integrated in LCA.

Methods

and Results. With a starting point in the conceptual structure and approach of life cycle impact assessment (LCIA), as developed by Helias Udo de Haes and the SETAC/UNEP Life Cycle Initiative, the paper identifies six damage categories under the general heading of human life and well-being. The paper proposes a comprehensive set of indicators, with units of measurement, and a first estimate of global normalisation values, based on incidence or prevalence data from statistical sources and severity scores from health state analogues. Examples are provided of impact chains linking social inventory indicators to impacts on both human well-being and productivity.

Recommendation and Perspective

It is suggested that human well-being measured in QALYs (Quality Adjusted Life Years) may provide an attractive single-score alternative to direct monetarisation.
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6.

Background and Objective

. Values in the known weighting methods in Life Cycle Assessment are mostly founded by the societal systems of developed countries. What source of weights and which weighting methods are reliable for a big developing country like China? The purpose of this paper is to find a possible weighting method and available data that will work well for LCA practices conducted in China. Since government policies and decisions play a leading role in the process of environmental protection in developing countries, the weights derived from political statements may be a consensus by representatives of the public.

Methods

'Distance-to-political target' principle is used in this paper to derive weights of five problem-oriented impact categories. The critical policy targets are deduced from the environmental policies issued in the period of the Ninth Five-year (1996-2000) and the Tenth Five-year (2001-2005) Plan for the Development of National Economy and Society of China. Policy targets on two five-year periods are presented and analyzed. Weights are determined by the quotient between the reference levels and target levels of a certain impact category.

Results and Discussion

Since the Tenth Five-year Plan put forward the overall objective to reduce the level of regional pollution by 2005, the weights for AP, EP and POCP for 2000-2005 are more than 1. By comparison between the Ninth Five-year and Tenth Five-year period, the results show that the weights obtained in this paper effectively represent Chinese political environmental priorities in different periods. For the weights derived from China's political targets for the overall period 1995-2005, the rank order of relative importance is ODP>AP>POCP>EP>GWP. They are recommended to the potential users for the broader disparity among the five categories. By comparison with the weights presented by the widespread EDIP method, the result shows that there's a big difference in the relative importance of ozone depletion and global warming.

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In conclusion, the weighting factors and rank order of impact categories determined in this study represent the characteristics of the big developing country. The derived weighting set can be helpful to LCA practices of products within the industrial systems of China.
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7.

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DOI: http://dx.doi.org/10.1065/lca2006.04.013

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Goal, Scope and background. Methodologies based on life cycle assessment have been developed to calculate the environmental impact of dwellings. Human health damages due to exposure of occupants to substances and noise emitted by road traffic are not included in these methodologies. In this study, a methodology has been developed to calculate damages to human health of occupants caused by substances and noise emitted by neighbourhood car traffic. The goal of this study is to assess the influence of the location of the dwelling on the health of the occupants, compared to the damage to human health associated with the rest of the life cycle of that dwelling.

Methods

Fate, exposure and human health effects were addressed in the calculation procedure. The methodology takes into account road traffic noise and four hazardous substances emitted by cars. Chemical fate factors were calculated with an outdoor exposure model for traffic pollutants, air entrance rates and indoor intake fractions. Fate factors for noise were based on noise levels generated by traffic. Effect factors for substances were based on unit risk factors and extrapolated dose-effect relationships. Effect factors for noise were based on linear relationships between noise level changes and health effects, while taking into account threshold values for noise levels for negative impacts. Damage factors were calculated on the basis of disability adjusted life years (DALYs). Human health damage scores for changes in traffic situations have been calculated for differences in three traffic scenarios in residential areas and for the Dutch reference dwellings.

Results and Discussion

For the Dutch reference dwelling and the traffic situations considered and taking into account noise, particulate matter (PM10), sulphur dioxide, benzene and benzo[ a]pyrene, communication disturbances and sleep disturbances due to noise and health effects of PM10 appear to be dominant in the total damage to human health of occupants caused by neighbourhood car traffic. A sensitivity analysis has shown that a reduction of the car and truck density and of the distance of the façade of the dwellings to the road axis has the largest positive effect on the human health of the occupants, and that a decrease of speed by traffic impediments has only a marginal or even a negative effect. Differences in overall indoor health damage due to different traffic scenarios may be 1.5 to 2 times

Conclusion

Within the limitations of this study, damages to human health of occupants due to indoor exposure to road traffic noise and pollutants appear to be in the same order of magnitude when compared with damages associated with the life cycle of dwellings. This emphasizes the importance to include the location of dwellings in the life cycle assessment of the dwelling.
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8.

Purpose

In order to understand the environmental impacts of various products, processes, or services, it should be possible to obtain life-cycle assessment (LCA) reports quickly and easily without having to delve into restricted access or hidden databases. The aim of this study is to assess the availability of environmental LCAs, water footprinting, and carbon footprinting studies conducted in New Zealand.

Methods

To review the quantitative availability of life-cycle assessment studies for New Zealand, simple online searches were performed using the Google and Google Scholar search engines. Additionally, ScienceDirect and Scopus were used to determine the availability of other peer-reviewed LCA-related reports.

Results and discussion

For the period under review, 20 documents were publicly available. Additionally, other searches conducted via ScienceDirect, Scopus and Google Scholar yielded a further 15 restricted documents. The results included data carbon- and water footprinting studies. The number of LCAs and carbon footprinting reports both exceeded those of water footprinting.

Conclusions

Over 35 studies were available through Internet searches. This number excludes wool which had six results (Scopus only) and many more through Google. These were not included due to possible repetition and miscounting of results.
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9.

Background

Current standard therapy for seizure prophylaxis in Neuro-surgical patients involves the use of Phenytoin (PHY). However, a new drug Levetiracetam (LEV) is emerging as an alternate treatment choice. We aimed to conduct a meta-analysis to compare these two drugs in patients with brain injury.

Methods

An electronic search was performed in using Pubmed, Embase, and CENTRAL. We included studies that compared the use of LEV vs. PHY for seizure prophylaxis for brain injured patients (Traumatic brain injury, intracranial hemorrhage, intracranial neoplasms, and craniotomy). Data of all eligible studies was extracted on to a standardized abstraction sheet. Data about baseline population characteristics, type of intervention, study design and outcome was extracted. Our primary outcome was seizures.

Results

The literature search identified 2489 unduplicated papers. Of these 2456 papers were excluded by reading the abstracts and titles. Another 25 papers were excluded after reading their complete text. We selected 8 papers which comprised of 2 RCTs and 6 observational studies. The pooled estimate’s Odds Ratio 1.12 (95% CI?=?0.34, 3.64) demonstrated no superiority of either drug at preventing the occurrence of early seizures. In a subset analysis of studies in which follow up for seizures lasted either 3 or 7?days, the effect estimate remained insignificant with an odds ratio of 0.96 (95% CI?=?0.34, 2.76). Similarly, 2 trials reporting seizure incidence at 6?months also had insignificant pooled results while comparing drug efficacy. The pooled odds ratio was 0.96 (95% CI?=?0.24, 3.79).

Conclusions

Levetiracetam and Phenytoin demonstrate equal efficacy in seizure prevention after brain injury. However, very few randomized controlled trials (RCTs) on the subject were found. Further evidence through a high quality RCT is highly recommended.
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10.

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DOI: http://dx.doi.org/10.1065/lca2006.04.015

Goal, Scope and Background

The weighting phase in Life Cycle Assessment (LCA) is and has always been a controversial issue, partly because this element requires the incorporation of social, political and ethical values. Despite the controversies, weighting is widely used in practise. In this paper we will present an approach for monetisation of environmental impacts which is based on the consistent use of ecotaxes and fees in Sweden as a basis for the economic values. The idea behind this approach is that taxes and fees are expressions of the values society places on resource uses and emissions. An underlying assumption for this is that the decisions taken by policy-makers are reflecting societal values thus reflecting a positive view of representative democracy.

Methods

In the method a number of different ecotaxes are used. In many cases they can directly be used as valuation weighting factors, an example is the CO2-tax that can be used as a valuation of CO2-emissions. In some cases, a calculation has to be made in order to derive a weighting factor. An example of this is the tax on nitrogen fertilisers which can be recalculated to an emission of nitrogen which can be used as a weighting factor for nitrogen emissions. The valuation weighting factors can be connected to characterisation methods in the normal LCA practise. We have often used the Ecotax method in parallel to other weighting methods such as the Ecoindicator and EPS methods and the results are compared.

Results and Discussion

A new set of weighting factors has been developed which has been used in case studies. It is interesting to note that the Ecotax method is able to identify different environmental problems as the most important ones in different case studies. In some cases, the Ecotax method has identified some interventions as the most important ones which lack weighting factors in other weighting methods. The midpoint-endpoint debate in the LCA literature has often centred on different types of uncertainties. Sometimes it is claimed that an advantage with having an endpoint approach is that the weighting would be easier and less uncertain. Here we are however suggesting a mid-point weighting method that we claim are no less uncertain than other often used weighting methods based on a damage assessment. This paper can therefore be seen as a discussion paper also in the midpoint-endpoint debate.

Conclusion and Recommendation

The Ecotax method is ready to use. It should be further updated and developed as taxes are changed and new characterisation methods are developed. The method is not only relevant for LCA but also for other environmental systems analysis. The Ecotax method has also been used as a valuation method for Cost-Benefit Analysis (CBA), Life Cycle Costing (LCC) and within the context of a Strategic Environmental Assessment (SEA).
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11.

Background

Until recently, plant metabolomics have provided a deep understanding on the metabolic regulation in individual plants as experimental units. The application of these techniques to agricultural systems subjected to more complex interactions is a step towards the implementation of translational metabolomics in crop breeding.

Aim of Review

We present here a review paper discussing advances in the knowledge reached in the last years derived from the application of metabolomic techniques that evolved from biomarker discovery to improve crop yield and quality.

Key Scientific Concepts of Review

Translational metabolomics applied to crop breeding programs.
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12.

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DOI: http://dx.doi.org/10.1065/lca2006.04.014

Background, Aims and Scope

In the life cycle of a product, emissions take place at many different locations. The location of the source and its surrounding conditions influence the fate of the emitted pollutant and the subsequent exposure it causes. This source of variation is normally neglected in Life Cycle Impact Assessment (LCIA), although it is well known that the impacts predicted by site-generic LCIA in some cases differ significantly from the actual impacts. Environmental impacts of photochemical ozone (ground-level ozone) depend on parameters with a considerable geographical variability (like emission patterns and population densities). A spatially differentiated characterisation model thus seems relevant.

Methods

and Results. The European RAINS model is applied for calculation of site-dependent characterisation factors for Non-Methane Volatile Organic Compounds (NMVOCs) and nitrogen oxides (NOx) for 41 countries or regions within Europe, and compatible characterisation factors for carbon monoxide (CO) are developed based on expert judgement. These factors are presented for three emission years (1990, 1995 and 2010), and they address human health impacts and vegetation impacts in two separate impacts categories, derived from AOT40 and AOT60 values respectively. Compatible site-generic characterisation factors for NMVOC, NOx, CO and methane (CH4) are calculated as emission-weighted European averages to be applied on emissions for which the location is unknown. The site-generic and site-dependent characterisation factors are part of the EDIP2003 LCIA methodology. The factors are applied in a specific case study, and it is demonstrated how the inclusion of spatial differentiation may alter the results of the photochemical ozone characterisation of life cycle impact assessment.

Discussion

and Conclusions. Compared to traditional midpoint characterisation modelling, this novel approach is spatially resolved and comprises a larger part of the cause-effect chain including exposure assessment and exceeding of threshold values. This positions it closer to endpoint modelling and makes the results easier to interpret. In addition, the developed model allows inclusion of the contributions from NOx, which are ne- glected when applying the traditional approaches based on Photochemical Ozone Creation Potentials (POCPs). The variation in site-dependent characterisation factors is far larger than the variation in POCP factors. It thus seems more important to represent the spatially determined variation in exposure than the difference in POCP among the substances.
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13.

Introduction

Metritis is an uterine pathology that causes economic losses for the dairy industry. It is associated with lower reproductive efficiency, increased culling rates, decreased milk production and increased veterinary costs.

Objectives

To gain a more detailed view of the urine metabolome and to detect metabolite signature in cows with metritis. In addition, we aimed to identify early metabolites which can help to detect cows at risk to develop metritis in the future.

Methods

We used nuclear magnetic resonance spectroscopy starting at 8 and 4 weeks prior to the expected day of parturition, during the week of diagnosis of metritis, and at 4 and 8 weeks after diagnosis of metritis in Holstein dairy cows.

Results

At 8 weeks before parturition, pre-metritic cows had a total of 30 altered metabolites. Interestingly, 28 of them increased in urine when compared with control cows (P?<?0.05). At 4 weeks before parturition, 34 metabolites were altered. At the week of diagnosis of metritis a total of 20 metabolites were altered (P?<?0.05). The alteration continued at 4 and 8 weeks after diagnosis.

Conclusions

The metabolic fingerprints in the urine of pre-metritic and metritic cows point toward excretion of multiple amino acids, tricarboxylic acid cycle metabolites and monosaccharides. Combination of galactose, leucine, lysine and panthotenate at 8 weeks before parturition might serve as predictive biomarkers for metritis.
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14.

Purpose

To evaluate the efficiency of corneal collagen cross-linking (CXL) in addition to topical voriconazole in cases with mycotic keratitis.

Design

Retrospective case series in a tertiary university hospital.

Participants

CXL was performed on 13 patients with mycotic keratitis who presented poor or no response to topical voriconazole treatment.

Methods

The clinical features, symptoms, treatment results and complications were recorded retrospectively. The corneal infection was graded according to the depth of infection into the stroma (from grade 1 to grade 3). The visual analogue scale was used to calculate the pain score before and 2 days after surgery.

Main Outcome Measures

Grade of the corneal infection.

Results

Mean age of 13 patients (6 female and 7 male) was 42.4 ± 17.7 years (20–74 years). Fungus was demonstrated in culture (eight patients) or cytological examination (five patients). Seven of the 13 patients (54%) were healed with topical voriconazole and CXL adjuvant treatment in 26 ± 10 days (15–40 days). The remaining six patients did not respond to CXL treatment; they initially presented with higher grade ulcers. Pre- and post-operative pain score values were 8 ± 0.8 and 3.5 ± 1, respectively (p < 0.05).

Conclusions

The current study suggests that adjunctive CXL treatment is effective in patients with small and superficial mycotic ulcers. These observations require further research by large randomized clinical trials.
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15.

Goal, Scope and Background

More and more national and regional life cycle assessment (LCA) databases are being established satisfying the increasing demand on LCA in policy making (e.g. Integrated Product Policy, IPP) and in industry. In order to create harmonised datasets in such unified databases, a common understanding and common rules are required. This paper describes major requirements on the way towards an ideal national background LCA database in terms of co-operation, but also in terms of life cycle inventory analysis (LCI) and impact assessment (LCIA) methodology.

Methods

A classification of disputed methodological issues is made according to their consensus potential. In LCI, three main areas of dissent are identified where consensus seems hardly possible, namely system modelling (consequential versus attributional), allocation (including recycling) and reporting (transparency and progressiveness). In LCIA the time aspect is added to the well-known value judgements of the weighting step.

Results and Discussions

It is concluded that LCA methodology should rather allow for plurality than to urge harmonisation in any case. A series of questions is proposed to identify the most appropriate content of the LCA background database or the most appropriate LCI dataset. The questions help to identify the best suited approach in modelling the product system in general and multioutput and recycling processes in particular. They additionally help to clarify the position with regard to time preferences in LCIA. Intentionally, the answers to these questions are not attributed to particular goal and scope definitions, although some recommendations and clarifying explanations are provided.

Recommendations and Perspective

It is concluded that there is not one single ideal background database content. Value judgements are also present in LCI modelling and require pluralistic solutions; solutions possibly based on the same primary data. It is recommended to focus the methodological discussion on aspects where consensus is within reach, sensible and of added value for all parties.
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16.

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DOI: http://dx.doi.org/10.1065/lca2006.04.017

Background, Aims and Scope

Social impacts in supply chains and product life cycles are of increasing interest to policy makers and stakeholders. Work is underway to develop social impact indicators for LCA, and to identify the social inventory data that will drive impact assessment for this category. Standard LCA practice collects and aggregates inventory data of the form \units of input or output (elementary flow) per unit of process output.\ Measurement of social impacts within workplaces as well as host communities and societies poses new challenges not heretofore faced by LCA database developers. Participatory measurement and auditing of social impacts and of workplace health issues has been shown to provide important benefits relative to external auditor-based methods, including greater likelihood of detecting rights abuses, and stronger support of subsequent action for improvement. However, nonstandardized auditing and metrics poses challenges for the supply chain-wide aggregation and comparison functions of LCA. An analogous challenge arises in the case of resource extractive processes, for which the certification of best management practices provides an important and practical environmental metric. In both the social and resource extraction examples, it may be that attributes of the process are more valuable metrics to measure and incentivize than measured quantities per unit of process output. But how to measure, how to aggregate across life cycles, how to compare product life cycles, and how to incentivize progress as with product policy?

Methods

A methodology is presented and demonstrated which estimates the health impacts of economic development stemming from product life cycles. This methodology does not introduce new social indicators; rather, it works with the already common LCA endpoint of human health, and introduces and applies a simplified empirical relationship to characterize the complex pathways from product life cycles' economic activity to health in the aggregate.

Results

A simple case study indicates that the health benefits of economic development impacts in product life cycles have the potential to be very significant, possibly even orders of magnitude greater than the health damages from the increased pollution. While the simple macro model points up the dramatic importance of socio-economic pathways to health in product life cycles, it lacks any sensitivity to the vitally important, contextspecific attributes of the economic development associated with each process. This result begs the question of how to measure, aggregate, compare, and stimulate society-wide improvement of context-dependent attributes within and across product life cycles in LCA.

Discussion

Before attempting an answer to the question noted above, a brief reconsideration is offered concerning life cycle assessment. Namely, where does it come from, and what does it bring?

Recommendations and Outlook

Finally, the paper concludes by sketching a life cycle approach to promoting localized assessments, to summarizing their results over supply chains and life cycles, and to comparing product life cycles in terms of their results. Often, localized assessments will yield information on the attributes of a process, rather than (or in addition to) the traditional form of life cycle inventory information, which is \units of something per unit of process output.\ The methodology can enable product policy users to promote reporting of basic attributes of processes within supply chains, together with local measurement and reporting of context-relevant impacts. For attributes linked to progress on impacts of local and global concern, promotion of these attributes within supply chain processes will bring strong benefits. In addition, over time it may be possible for researchers to develop and refine models that estimate, based on cross-sectional and time series analysis of attributes and impacts, relationships between attributes and impacts. In any case, while local impacts across supply chains may not be precisely knowable – let alone controllable – by a microdecision maker at the time of their product-related decision, life cycle attribute analysis may give such decision makers an opportunity to empower progress throughout life cycles and supply chains, which is after all a motivating goal of LCA.
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17.

Context

Patients with chronic fatigue syndrome and those with orthostatic intolerance share many symptoms, yet questions exist as to whether CFS patients have physiological evidence of orthostatic intolerance.

Objective

To determine if some CFS patients have increased rates of orthostatic hypotension, hypertension, tachycardia, or hypocapnia relative to age-matched controls.

Design

Assess blood pressure, heart rate, respiratory rate, end tidal CO2 and visual analog scales for orthostatic symptoms when supine and when standing for 8 minutes without moving legs.

Setting

Referral practice and research center.

Participants

60 women and 15 men with CFS and 36 women and 4 men serving as age matched controls with analyses confined to 62 patients and 35 controls showing either normal orthostatic testing or a physiological abnormal test.

Main outcome measures

Orthostatic tachycardia; orthostatic hypotension; orthostatic hypertension; orthostatic hypocapnia or combinations thereof.

Results

CFS patients had higher rates of abnormal tests than controls (53% vs 20%, p < .002), but rates of orthostatic tachycardia, orthostatic hypotension, and orthostatic hypertension did not differ significantly between patients and controls (11.3% vs 5.7%, 6.5% vs 2.9%, 19.4% vs 11.4%, respectively). In contrast, rates of orthostatic hypocapnia were significantly higher in CFS than in controls (20.6% vs 2.9%, p < .02). This CFS group reported significantly more feelings of illness and shortness of breath than either controls or CFS patients with normal physiological tests.

Conclusion

A substantial number of CFS patients have orthostatic intolerance in the form of orthostatic hypocapnia. This allows subgrouping of patients with CFS and thus reduces patient pool heterogeneity engendered by use of a clinical case definition.
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18.

Background

GAW20 working group 5 brought together researchers who contributed 7 papers with the aim of evaluating methods to detect genetic by epigenetic interactions. GAW20 distributed real data from the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) study, including single-nucleotide polymorphism (SNP) markers, methylation (cytosine-phosphate-guanine [CpG]) markers, and phenotype information on up to 995 individuals. In addition, a simulated data set based on the real data was provided.

Results

The 7 contributed papers analyzed these data sets with a number of different statistical methods, including generalized linear mixed models, mediation analysis, machine learning, W-test, and sparsity-inducing regularized regression. These methods generally appeared to perform well. Several papers confirmed a number of causative SNPs in either the large number of simulation sets or the real data on chromosome 11. Findings were also reported for different SNPs, CpG sites, and SNP–CpG site interaction pairs.

Conclusions

In the simulation (200 replications), power appeared generally good for large interaction effects, but smaller effects will require larger studies or consortium collaboration for realizing a sufficient power.
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19.

Objective

The coronary sinus Reducer is a recently introduced device to treat patients with severe angina symptoms refractory to optimal medical therapy and not amenable for conventional revascularisation. We aimed to assess the safety and efficacy of the Reducer in a real-world cohort of patients with refractory angina.

Methods

This is a single-centre retrospective registry. Patients with severe angina symptoms, objective evidence of myocardial ischaemia using any adequate non-invasive modality and without options for conventional revascularisation were regarded eligible for Reducer implantation.

Results

Twenty-three patients (74?% male, mean age 70?±?8 years, 91.3?% previous bypass surgery, 82.6?% previous percutaneous intervention, 47.8?% previous myocardial infarction, 52.2?% diabetes mellitus) underwent Reducer implantation. The safety endpoint (successful implantation of the first device without device-related adverse events) was met in all patients. After a median follow-up of 9 (8–14) months the efficacy (any reduction in Canadian Cardiovascular Society (CCS) class and revascularisation-free survival) was reached in 17 patients (74?%): 8 patients (34.8?%) improved by 1 CCS class, 7 (30.4?%) by 2 CCS classes and 2 (8.7?%) by 3 CCS classes. One patient died 4 months after implantation because of progressive heart failure (not associated with Reducer implantation).

Conclusion

In this single-centre real-world experience, Reducer implantation was safe and demonstrated excellent clinical efficacy in the treatment of refractory angina at mid-term follow-up.
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20.

Purpose

The article presents the method and results of the life cycle assessments (LCAs) of the Vestas' 2-MW GridStreamer TM wind turbines and outlines the state-of-the-art approach adopted. For more than 10 years, Vestas has prepared LCAs of wind power. However, since 2010, a step change in comprehensiveness has been employed, for example, conducting the LCA to individually assess all components within a wind turbine (being composed of around 25,000 parts).

Methods

Three LCAs have been conducted with the 2-MW GridStreamerTM turbines in accordance with ISO 14040/44 and critically reviewed by an expert. The goal was to evaluate potential environmental impacts and other non-impact indicators per kilowatt hour of electricity generated for a ‘typical’ 50-MW onshore wind plant.The LCAs assessed all life cycle stages and were built using GaBi DfX software. A significant quantity of primary data were gathered, for example, covering over 100 Vestas' sites for manufacturing, sales and servicing, as well as establishing turbine use-phase performance (i.e. electricity generation, servicing, etc.) based on over 20,000 monitored wind turbines around the world, covering around 20 % of the current worldwide installed capacity.

Results and discussion

The baseline results show that per kilowatt hour of electricity generated by the 2-MW GridStreamer? turbines have the following baseline performance: ADP elements 0.44 to 0.58 mg Sb-e, ADP fossil 0.10 to 0.13 MJ; acidification potential 37 to 45 mg SO2-e, eutrophication potential 3.7 to 4.5 mg PO4-e, freshwater aquatic ecotoxicity 100 to 130 mg DCB-e, global warming potential 7 to 10 g CO2-e, human toxicity potential 1,150 to 1,400 mg DCB-e, marine aquatic ecotoxicity potential 1,100 to 1,300 g DCB-e, photochemical oxidant creation 4 to 5 mg ethene, terrestrial ecotoxicity potential 19 to 24 mg DCB-e, return-on energy 8 to 11 months and recyclability 81 to 85 % of turbine mass.Being equipped with extensive facts and comprehensive LCA models provides Vestas the basis to further integrate environmental considerations into product marketing, design and research, procurement and to deliver transparent information to stakeholders.

Conclusions

Overall, the article presents a case study of the LCA approach used to assess the potential impacts of 2-MW GridStreamer? turbines based upon comprehensive product knowledge and represents a state-of-the-art approach to LCA modelling of wind power. The article discusses further applications of LCA internally to direct product improvement and for external communications and also highlights the LCAs' aim to improve transparency and robustness of previous LCAs of wind power.
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