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1.
How Can the Eco‐efficiency of a Region be Measured and Monitored?   总被引:2,自引:0,他引:2  
The concept of eco-efficiency is commonly referred to as a business link to sustainable development. In this article, ecoefficiency is examined at a regional level as an approach to promoting the competitiveness of economic activities in the Finnish Kymenlaakso region and mitigating their harmful impacts on the environment. The aim is to develop appropriate indicators for monitoring changes in the eco-efficiency of the region. A starting point is to produce indicators for the environmental and economic dimensions of regional development and use them for measuring regional eco-efficiency. The environmental impact indicators are based on a life-cycle assessment method, producing different types of environmental impact indicators: pressure indicators (e.g., emissions of CO2), impact category indicators (e.g., CO2 equivalents in the case of climate change), and a total impact indicator (aggregating different impact category indicator results into a single value). Environmental impact indicators based on direct material input, total material input, and total material requirement of the Kymenlaakso region are also assessed. The economic indicators used are the gross domestic product, the value added, and the output of the main economic sectors of Kymenlaakso. In the eco-efficiency assessment, the economic and environmental impact indicators are monitored in the same graph. In a few cases eco-efficiency ratios can also be calculated (the economic indicators are divided by the environmental indicators). Output (= value added + intermediate consumption) is used as an economic indicator related to the environmental impact indicators, which also cover the upstream processes of the region's activities. In the article, we also discuss the strengths and weaknesses of using the different environmental impact indicators.  相似文献   
2.

Aim, Scope and Background  

Aquatic eutrophication is a widespread problem in inland and coastal waters around the world and it should therefore be one of the impact categories to be considered in LCA studies of products and services. In LCAs there are several impact assessment methods to determine characterisation factors for eutrophying nutrients, but few methods have been developed to model fate and spatial aspects. One such method was developed as part of an LCA application of the Finnish forest industry. The aim of this study was to present this characterisation method in which the potential contributions of nitrogen and phosphorus to eutrophication of aquatic ecosystems are calculated. The use of the method was demonstrated by producing site/sector-specific characterisation factors and by constructing a reference value of aquatic eutrophication for Finland. A discussion of sensitivity and uncertainty aspects related to input data is also presented.  相似文献   
3.

Aim

Interleukin-10 (IL-10) has been associated with wheezing and asthma in children and the genetic variation of the IL-10 cytokine production may be linked to post-bronchiolitis lung function. We used impulse oscillometry (IOS) to evaluate the associations of IL10 polymorphisms with lung function at a median age of 6.3 years in children hospitalised for bronchiolitis before six months of age.

Methods

We performed baseline and post-exercise IOS on 103 former bronchiolitis patients. Data on single nucleotide polymorphisms (SNP) of IL10 rs1800896 (–1082G/A), rs1800871 (–819C/T), rs1800872 (–592C/A) were available for 99 children and of IL10 rs1800890 (–3575T/A) for 98 children.

Results

IL10 rs1800896, rs1800871 and rs1800872 combined genotype AA+CT+CA and carriage of haplotype ATA, respectively, were associated with higher resistance and lower reactance in baseline IOS in adjusted analyses. At IL10 rs1800890, the A/A-genotype and carriers of A-allele were associated with lower reactance in baseline IOS. There were no significant associations between the studied SNPs and airway hyper-reactivity to exercise.

Conclusion

Low-IL-10-producing polymorphisms in the IL-10 encoding gene were associated with obstructive lung function parameters, suggesting an important role for IL-10 in development of lung function deficit in early bronchiolitis patients.  相似文献   
4.
5.
The pathogenesis of aortic valve stenosis (AS) is characterized by the accumulation of LDL-derived cholesterol in the diseased valves. Since LDL particles also contain plant sterols, we investigated whether plant sterols accumulate in aortic valve lesions. Serum samples were collected from 82 patients with severe AS and from 12 control subjects. Aortic valves were obtained from a subpopulation of 21 AS patients undergoing valve surgery and from 10 controls. Serum and valvular total cholesterol and noncholesterol sterols were measured by gas-liquid chromatography. Noncholesterol sterols, including both cholesterol precursors and sterols reflecting cholesterol absorption, were detected in serum samples and aortic valves. The higher the ratios to cholesterol of the cholesterol precursors and absorption markers in serum, the higher their ratios in the stenotic aortic valves (r=0.74, P<0.001 for lathosterol and r=0.88, P<0.001 for campesterol). The valvular ratio to cholesterol of lathosterol correlated negatively with the aortic valve area (r= -0.47, P=0.045), suggesting attenuation of cholesterol synthesis with increasing severity of AS. The higher the absorption of cholesterol, the higher the plant sterol contents in stenotic aortic valves. These findings suggest that local accumulation of plant sterols and cholesterol precursors may participate in the pathobiology of aortic valve disease.  相似文献   
6.
We studied whether diameters of coronary arteries can be measured accurately with the use of transthoracic echocardiography (TTE). By knowing the anatomic diameter of the coronary artery together with coronary flow velocity it is possible to measure coronary flow volume more precisely by TTE. However, the suitability of TTE for measurement of diameters of all main epicardial coronary arteries has not been systematically validated. We measured the diameters of the left main (LM), left anterior descending (LAD), left circumflex (LCX), and right coronary arteries (RCA) with the use of TTE [manual two-dimensional (2D), color-Doppler, and automated 2D analysis] in 30 patients who had normal coronary anatomy. We compared these diameters to those measured with quantitative coronary angiography (QCA). We could measure diameters of LM, LAD, LCX, and RCA by TTE in up to 37%, 63%, 7%, and 60% of patients, respectively. The overall correlation coefficients between TTE and QCA measurements were 0.83 (P < 0.01) with manual 2D analysis, 0.82 (P < 0.01) with automated 2D analysis, and 0.94 (P < 0.01) with a color-Doppler-based analysis. Interobserver variability of TTE measurements was low (coefficient of variation 5.4 +/- 4.6-7.5 +/- 8.8%). TTE is an accurate method to evaluate coronary artery diameter in patients with healthy coronary arteries.  相似文献   
7.
Radiostereometric analysis (RSA) has become one of the recommended techniques for pre-market evaluation of new joint implant designs. In this study we evaluated the effect of repositioning of X-ray tubes and phantom model on the precision of the RSA method. In precision measurements, we utilized mean error of rigid body fitting (ME) values as an internal control for examinations. ME value characterizes relative motion among the markers within each rigid body and is conventionally used to detect loosening of a bone marker. Three experiments, each consisting of 10 double examinations, were performed. In the first experiment, the X-ray tubes and the phantom model were not repositioned between one double examination. In experiments two and three, the X-ray tubes were repositioned between one double examination. In addition, the position of the phantom model was changed in experiment three. Results showed that significant differences could be found in 2 of 12 comparisons when evaluating the translation and rotation of the prosthetic components. Repositioning procedures increased ME values mimicking deformation of rigid body segments. Thus, ME value seemed to be a more sensitive parameter than migration values in this study design. These results confirmed the importance of standardized radiographic technique and accurate patient positioning for RSA measurements. Standardization and calibration procedures should be performed with phantom models in order to avoid unnecessary radiation dose of the patients. The present model gives the means to establish and to follow the intra-laboratory precision of the RSA method. The model is easily applicable in any research unit and allows the comparison of the precision values in different laboratories of multi-center trials.  相似文献   
8.
The volatile organic compound composition (VOCs) of printing press air wasfound to contain mostly ethanol, but also ethyl acetate, 1-propanol, 2-propanol,1-methoxy-2-propanol and 3-ethoxy-1-propanol. A pilot plant bioscrubber inoculatedwith a mixed microbial population was constructed on-site. The bioscrubber wasable to treat the polluted gas efficiently. It, however, suffered from strong wall growthand blockages in the column. The efficiencies of the pilot plant and a bioreactor iscompared. The yeasts Candida guilliermondii and Saccharomyces cerevisiae known to tolerate ethanol were selected instead of mixed population to avoid the wall growth and blockages in the bioreactor. The removal of the VOCs both individually and as a complex mixture was tested in a microcultivation system and in continuous chemostat cultures with and without cell recycling. The Candida yeast could use all the compounds as a carbon source while growth of S. cerevisiae was markedly slower on the methoxylated and ethoxylated propanols. Best total removal of the VOCs was 99% and achieved by C. guilliermondii. The only compound that was not totally removable in the chemostat experiment with C. guilliermondii was 1-methoxy-2-propanol. In laboratory scale the total and volumetric removal of VOCs by C. guilliermondii was more efficient compared to the pilot plant encouraging to scale up and applying the yeast bioreactor to real field conditions.  相似文献   
9.

Purpose

There has been lively debate, especially in Finland and Sweden, on the climate impacts of peat fuel. Previous studies of peat fuel's life-cycle climate impacts were controversial in their interpretation. The aim of this paper is conclusive examination of the issues of LCA methodology, derived from critical review of previous studies and recalculation based on the latest knowledge of greenhouse gas balances related to peat fuel’s utilisation and the radiative forcing impacts of greenhouse gases.

Methods

The most recent findings on emissions and the gas fluxes between soil, vegetation and atmosphere were used in calculation of the life-cycle climate impacts of the various peat fuel utilisation chains by means of LCA methodology. In the main, the calculation methods and rules were the same as in the previous studies, with the aim being to distinguish the impact of peat fuel’s utilisation from that of the natural or semi-natural situation. A dynamic method was employed for assessing changes in radiative forcing. The results of alternative peat fuel utilisation chains were compared to the corresponding result for coal.

Results

There are many steps in peat fuel LCA, where different assumptions lead to different outcomes. Determining the functional unit, reference situations and system boundaries, as well as the emission calculation methods, is important from this point of view. Determination of the initial reference situation emerged as one of the critical points in the calculations. Time scale can strongly affect the final outcomes in a study where effects of long-term land-use change are considered.

Conclusions

Each peatland area is unique. The higher the greenhouse gas emissions in the initial reference situation, the greater is the climate impact of the area and the more suitable the area is for peat extraction. The study showed that more greenhouse gas flux measurements are needed, for better assessment of the climate impacts of different potential peat extraction sites. Climate change mitigation requires quick actions, and uncertainties related to emissions are higher for longer time spans. Therefore, it can be concluded that a perspective spanning more than 100 years is inappropriate in peat fuel's life-cycle climate impact assessments.  相似文献   
10.
The kidney filtration barrier consists of the capillary endothelium, the glomerular basement membrane and the slit diaphragm localized between foot processes of neighbouring podocytes. We report that collagen XVII, a transmembrane molecule known to be required for epithelial adhesion, is expressed in podocytes of normal human and mouse kidneys and in endothelial cells of the glomerular filtration barrier. Immunoelectron microscopy has revealed that collagen XVII is localized in foot processes of podocytes and in the glomerular basement membrane. Its role in kidney has been analysed in knockout mice, which survive to birth but have high neonatal mortality and skin blistering and structural abnormalities in their glomeruli. Morphometric analysis has shown increases in glomerular volume fraction and surface densities of knockout kidneys, indicating an increased glomerular amount in the cortex. Collagen XVII deficiency causes effacement of podocyte foot processes; however, major slit diaphragm disruptions have not been detected. The glomerular basement membrane is split in areas in which glomerular and endothelial basement membranes meet. Differences in the expression of collagen IV, integrins α3 or β1, laminin α5 and nephrin have not been observed in mutant mice compared with controls. We propose that collagen XVII has a function in the attachment of podocyte foot processes to the glomerular basement membrane. It probably contributes to podocyte maturation and might have a role in glomerular filtration.  相似文献   
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