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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.
Thirty postmenopausal women (11 omnivores, 10 vegetarians and 9 apparently healthy women with surgically removed breast cancer) were investigated with regard to the association of their urinary excretion of estrogens, lignans and isoflavonoids (all diphenols) with plasma sex hormone binding globulin (SHBG). A statistically significant positive correlation between urinary total diphenol excretion and plasma SHBG was found which remained statistically significant after elimination of the confounding effect of body mass determined by body mass index (BMI). Furthermore we found a statistically significant negative correlation between plasma SHBG and urinary excretion of 16α-hydroxyestrone and estriol which also remained significant after eliminating the effect of BMI. Furthermore we observed that enterolactone (Enl) stimulates the synthesis of SHBG by HepG2 liver cancer cells in culture acting synergistically with estradiol and at physiological concentrations. Enl was rapidly conjugated by the liver cells, mainly to its monosulfate. Several lignans and the isoflavonoids daidzein and equol were found to compete with estradiol for binding to the rat uterine type II estrogen binding site (the s.c. bioflavonoid receptor). It is suggested that lignans and isoflavonoids may affect uptake and metabolism of sex hormones by participating in the regulation of plasma SHBG levels and in this way influence their biological activity and that they may inhibit cancer cell growth like some flavonoids by competing with estradiol for the type II estrogen binding sites.  相似文献   
3.
High light treatments were given to attached leaves of pumpkin (Cucurbita pepo L.) at room temperature and at 1°C where the diffusion- and enzyme-dependent repair processes of Photosystem II are at a minimum. After treatments, electron transfer activities and fluorescence induction were measured from thylakoids isolated from the treated leaves. When the photoinhibition treatment was given at 1°C, the Photosystem II electron transfer assays that were designed to require electron transfer to the plastoquinone pool showed greater inhibition than electron transfer from H2O to paraphenyl-benzoquinone, which measures all PS II centers. When the light treatment was given at room temperature, electron transfer from H2O to paraphenyl-benzoquinone was inhibited more than whole-chain electron transfer. Variable fluorescence measured in the presence of ferricyanide decreased only during room-temperature treatments. These results suggest that reaction centers of one pool of Photosystem II, non-QB-PS II, replace photoinhibited reaction centers at room temperature, while no replacement occurs at 1°C. A simulation of photoinhibition at 1°C supports this conclusion.Abbreviations BSA bovine serum albumin - Chl chlorophyll - DCMU 3-(3,4,-dichlorophenyl)-1,1,-dimethylurea - DCPIP dichlorophenol-indophenol (2,6-dichloro-4((4-hydroxyphenyl)imino)-2,5-cyclohexadien-1-one) - DPC diphenyl carbazide (2,2-diphenylcarbonic dihydrazide) - FeCN ferricyanide (hexacyanoferrate(III)) - app apparent quantum yield of photosynthetic oxygen evolution - MV methyl viologen (1,1-dimethyl-4,4-bipyridinium dichloride) - PPBQ phenyl-p-benzoquinone - PPFD photosynthetic photon flux density - PQ pool plastoquinone - QB secondary quinone acceptor of PS II - RT room temperature - WC whole chain electron transfer  相似文献   
4.
The densities of microtine rodents and their main predators,small mustelids, fluctuate synchronously in 3–5-year cyclesin central and northern Fennoscandia. Predation by small mustelidshas been suggested as one of the driving forces in microtinecyclicity, causing deep synchronous declines of several volespecies. We studied experimentally the effects of small mustelidson mating behavior, foraging, and breeding in nonwintered fieldvoles (Microtus agrestis) originating from a cyclic population.By using mustelid odors, we simulated a crash phase environmentwith high predation risk for breeding pairs of voles. In ourexperiments, 87% of the female field voles suppressed breedingwhen exposed to mustelid odors. Both female and male behaviorchanged, and no mating behaviors were observed under the simulatedpredation risk. Weights of both sexes decreased when exposedto mustelid odor, probably due to decreased foraging; weightsof the control females increased due to pregnancy; and no weightchanges occurred in control males. Decreased breeding and foragingpossibilities under high predation pressure may form the basisfor the ultimate explanation for breeding suppression. Thereare at least two different mechanisms for breeding suppression:either mating does not take place or malnutrition in femalesdoes not' allow breeding to occur. Delayed breeding under highrisk of predation, for whatever reason, could increase the probabilityof individuals, especially that of the females, to survive overthe crash to the next, safer breeding season when their youngwould have better possibilities to survive.  相似文献   
5.
Bone mineral density (BMD) in the femoral neck and lumbar spine was measured for 355 postmenopausal 48- to 56-year-old women and the BMD in five different regions in the mandible for 77. All 355 women were also classified according to the size of the masseter muscle. Both skeletal measures and the BMD of the buccal cortex distally from the foramen mentale were compared with the size of the masseter muscle. This study indicates that functional stress, caused by the masseter muscle, is involved in maintaining bone mineral density in edentulous regions of the mandible. Those individuals who are physically active or are bruxists may lose less mineral, after extractions of teeth, from those regions of the jaw bones where the muscles are attached.  相似文献   
6.
A susceptibility gene on chromosome 18 and a parent-of-origin effect have been suggested for bipolar affective disorder (BPAD). We have studied 28 nuclear families selected for apparent unilineal transmission of the BPAD phenotype, by using 31 polymorphic markers spanning chromosome 18. Evidence for linkage was tested with affected-sib-pair and LOD score methods under two definitions of the affected phenotype. The affected-sib-pair analyses indicated excess allele sharing for markers on 18p within the region reported previously. The greatest sharing was at D18S37: 64% in bipolar and recurrent unipolar (RUP) sib pairs (P = .0006). In addition, excess sharing of the paternally, but not maternally, transmitted alleles was observed at three markers on 18q: at D18S41, 51 bipolar and RUP sib pairs were concordant for paternally transmitted alleles, and 21 pairs were discordant (P = .0004). The evidence for linkage to loci on both 18p and 18q was strongest in the 11 paternal pedigrees, i.e., those in which the father or one of the father's sibs is affected. In these pedigrees, the greatest allele sharing (81%; P = .00002) and the highest LOD score (3.51; θ = 0.0) were observed at D18S41. Our results provide further support for linkage of BPAD to chromosome 18 and the first molecular evidence for a parent-of-origin effect operating in this disorder. The number of loci involved, and their precise location, require further study.  相似文献   
7.
Niche relations among dung-inhabiting beetles   总被引:1,自引:0,他引:1  
I. Hanski  H. Koskela 《Oecologia》1977,28(3):203-231
Summary The whole dung-inhabiting (adult) beetle community living in southern Finland was studied with reference to the seasonal (6 summer months), macrohabitat (open field, half-open pine forest and closed spruce forest) and successional (30 days) gradients. The material comprised 50 coprophagous and 129 carnivorous species, represented by 26,650 and 35,850 individuals, respectively. The most important characteristics of each species are given in an Appendix.In the coprophages the species-abundance relations fitted the lognormal distribution well, but in the carnivores the distribution was strikingly less even. A great number of other differences (see below) apparent between the two trophic groups were explained as the result of a difference in the degree of specialization, apart from the difference in their trophic position: coprophages are microhabitat (dung) and food specialists, while carnivores are microhabitat generalists (and therefore their critical niche space was not completely covered in this study).In the coprophages, two important species guilds were observed: the first occurred at the very geginning of the succession (mean position 2.5 days), and consisted mainly of true dung specialists; the second guild contained species with wider utilization along the successional dimension (mean position 6.5 days), and species of more generalist nature (saprophages). The utilization of carnivores along the successional gradient was more continuous, probably because of their more diversified food resources. The total niche width among the coprophages increased from early successional species to species occurring mainly later on, but was more constant in carnivores. The environmental dimensions proved to be totally independent of each other among the carnivores, while the coprophages showed a clear supplementary relationship along them. Among the carnivores, a spherical niche shape dominated, but among the coprophages elongated and disk-liked shapes were also well represented, especially in specialist species. In both groups, a significant positive correlation existed between niche width and dominance, but not between niche width and abundance. It is suggested that the patchy distribution and transient occurrence of suitable microhabitats contributes to the coexistence of many ecologically similar species.  相似文献   
8.
Illumination of intact pumpkin leaves with high light led to severe photoinhibition of photosystem II with no net degradation of the D1 protein. Instead, however, a modified form of D1 protein with slightly slower electrophoretic mobility was induced with corresponding loss in the original form of the D1 protein. When the leaves were illuminated in the presence of chloramphenicol the modified form was degraded, which led to a decrease in the total amount of the D1 protein. Subfractionation of the thylakoid membranes further supported the conclusion that the novel form of the D1 protein was not a precursor but a high-light modified form that was subsequently degraded.  相似文献   
9.
The structure of seven local bumblebee communities was studied in eastern Finland. The number of species in the study sites varied from 5 to 10, 11 being the number in the species pool. Most of the species (queens) had proboscis lengths of 8–11 mm. When floral resources were analysed on the basis of corolla tube depths, a group was found between 4 and 8 mm. In terms of flower utilization, species with similar proboscises had higher pairwise niche overlaps than species differing by their proboscis lengths.
Spacing between neighbouring species along the proboscis length dimension was not more uniform in the realized communities than what was expected on the basis of random draws from the local species pool. The results were the same for all species observed in the communities and for the abundant species only (frequency >5%), although competition among species in the latter group is expected to be more intense.
When the structure of bumblebee communities and of floral resources was expressed in terms of diversity of proboscis lengths and corolla tube depths, respectively, a positive correlation was found. Data suggest that species with similar proboscis tend to co-occur on fields with availability of appropriate corolla tubes.  相似文献   
10.
Thirteen severely retarded patients with Salla disease, a new type of lysosomal storage disorder, have been studied biochemically. All patients excreted approximately ten times more free sialic acid than normal individuals. The isolated sialic acid was characterized by paper chromatography, thin-layer chromatography, optical rotation, 13C and 1H nuclear magnetic resonance spectroscopy, and mass spectrometry of its permethylated derivative. The results clearly indicated that the excreted sialic acid was identical to N-acetylneuraminic acid. The main sialylated trisaccharide present in the urine of the patients was identified as 3'-sialyllactose by sugar and methylation analysis. The excreted amounts were found to be within normal range.  相似文献   
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