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41.

Purpose

Life cycle assessment (LCA) is being used increasingly in decision support situations. In actual cases, the sources of uncertainty are easily hidden in the complexity. Methods for taking uncertainty into account are recommended by LCA guidelines, but actual application remains rare. The aim of this study is to demonstrate the sources of uncertainty in a practical simple selection case wherein a customer makes a decision between beer and wine in a restaurant, considering the selected criteria and the given information. The uncertainty in LCA results is connected to the broader scope of decision analysis.

Methods

Life cycle inventories were collected for beer and wine production from existing literature. The functional unit was chosen to be one serving of alcohol: beer or wine. For illustrative purposes, only the global warming potential indicator was included in the LCA through carbon footprint (CF). Probabilistic uncertainty analysis was applied to the CF system using Monte Carlo simulation. Water footprint was also roughly considered. In addition, three non-environmental indicators were included in the decision: weight control, price, and taste. The comparison between the two products was constructed as a multiple-criteria decision analytical problem.

Results and discussion

The results indicated that beer had, on average, a higher CF value than wine did. However, the difference was not significant, and within the uncertainty range, also the opposite conclusion was possible. The ratio of wine to beer CF was dominated by the uncertainty in the N2O emissions of wine production. When all of the decision criteria were included, the level of uncertainty prevented robust overall conclusions about preference for beer or wine. However, depending on the utility differences assigned to subjective indicators, there existed also cases wherein decisions could be made at a 10?% risk level regardless of high overall uncertainty.

Conclusions

In many cases, the uncertainties of LCA are dwarfed by the overall uncertainty of the decision situation. However, as shown by our example, in many cases, reasonable decisions can be made in spite of high uncertainties. The uncertainties of single LCA indicators should be considered in relation to the decision-making problem, which depends on the uncertainty of LCA indicators but also significantly on the weighting of the indicators and the related uncertainty. Successful decision making depends on both the magnitude of uncertainty and the differences in expected utility value between alternatives. More attention should be paid to uncertainty analysis considering the weighting factors.  相似文献   
42.
Chymase released from activated mast cells induces apoptosis of vascular smooth muscle cells (SMCs) in vitro by degrading the pericellular matrix component fibronectin, so causing disruption of focal adhesion complexes and Akt dephosphorylation, which are necessary for cell adhesion and survival. However, the molecular mechanisms of chymase-mediated apoptosis downstream of Akt have remained elusive. Here, we show by means of RT-PCR, Western blotting, EMSA, immunocytochemistry and confocal microscopy, that chymase induces SMC apoptosis by disrupting NF-kappaB-mediated survival signaling. Following chymase treatment, the translocation of active NF-kappaB/p65 to the nucleus was partly abolished and the amount of nuclear p65 was reduced. Pretreatment of SMCs with chymase also inhibited LPS- and IL-1beta-induced nuclear translocation of p65. The chymase-induced degradation of p65 was mediated by active caspases. Loss of NF-kappaB-mediated transactivation resulted in downregulation of bcl-2 mRNA and protein expression, leading to mitochondrial swelling and release of cytochrome c. The apoptotic process involved activation of both caspase 9 and caspase 8. The results reveal that, by disrupting the NF-kappaB-mediated survival-signaling pathway, activated chymase-secreting mast cells can mediate apoptosis of cultured arterial SMCs. Since activated mast cells colocalize with apoptotic SMCs in vulnerable areas of human atherosclerotic plaques, they may participate in the weakening and rupture of atherosclerotic plaques.  相似文献   
43.
In the construction of luminescent yeast cell based fibre-optic biosensors, we demonstrate a novel approach for estrogenic endocrine disrupting chemical (EDC) biodetection by entrapping genetically modified Saccharomyces cerevisiae cells, containing the estrogen receptor alpha-mediated expression of the luc reporter gene, in hydrogel matrices based on calcium alginate or PVA. In order to insure a significant signal, an optimal immobilization ratio of 1:2 alginate 3% (w/v): 5 × 106 [cells/ml], respectively, was used with the highest 17-β-estradiol (β-E2) induction factor after 2.5 h of incubation with 10 [nM] β-E2. It was shown that biocompatible alginate beads, 4.27–4.55 × 105 [CFU/bead], which were characterized by a detection limit of 0.08 [μg l−1] and an EC50 of 0.64 [μg l−1] for β-E2, retained their viability for luminescence measurements after 1 month of storage at −80 °C slow freeze condition, and thus repeated cell cultivations were not required. The assay reproducibility for each tested EDC, represented by the coefficients of variation (CV), ranged from 4.35 to 18.47%. An alternative immobilization method, based on a room temperature partial drying of polyvinyl alcohol (PVA) solution (LentiKat® Liquid) and cell suspension mix, was investigated with only a slightly lower detection limit for β-E2 than that reported with alginate beads. Alginate yeast based hydrogels may also be applicable to the analysis of environmental water samples since the trend of detected estrogenic activities with alginate beads roughly correlated with LC–MS–MS analytical results.  相似文献   
44.
We explored the reproductive modes of Ulva intestinalis in the inner part of the Baltic Sea during three consecutive years by using five microsatellite loci to estimate the relative abundance of diploid sporophytes and haploid gametophytes. Our results suggest that both diploid sporophytes and haploid gametophytes occur regularly in the Baltic Sea. The ratio of haploid to diploid individuals changes with seasons. Sporophytes are more abundant than gametophytes throughout the year, but the proportion of haploids increases from 10% in early summer to 35% in September. The over-wintering takes primarily place as diploid spores released by sporophytes. The sporophytes appear to reproduce both sexually and asexually in the Baltic Sea, since clones were found for this life phase. The fraction of individuals which belonged to an apparent diploid clone was higher in spring (62%) than in autumn (33%). We also found evidence for asexual clones in haploid gametophytes. The presence of both diploid and haploid individuals and the pattern of genetic and genotypic diversity provide evidence of sexual reproduction in the Baltic Sea. Thus the sporophytes and gametophytes do not function as two reproductively separate units. Compared with many other algal species with a reduced reproductive cycle in low salinity, U. intestinalis differs by having a multitude of reproductive modes also in the brackish water Baltic Sea, which can in part explain the dynamic propagation and high adaptability of the species.  相似文献   
45.
Takala T 《Bioethics》1999,13(3-4):288-293
One of the much debated issues around the evolving human genetics is the question of the right to know versus the right not to know. The core question of this theme is whether an individual has the right to know about her own genetic constitution and further, does she also have the right to remain in ignorance. Within liberal traditions it is usually held that people, if they so wish, have the right to all the knowledge available about themselves. This right is based on the value of autonomy or on the right of self-determination, and it is sometimes partly justified as a countermeasure to the authorities' control over people. I do not wish to deny the right to genetic knowledge (about oneself). I think that its existence is self-evident. The argument I want to put forth in this paper is that in liberal societies we should acknowledge people's right to remain in ignorance as well. The only reason for not doing this would be that grave harm to others would follow if people were allowed to make these seemingly self-regarding decisions. Arguments presented against the right to ignorance are twofold. First there are those arguing against the right to ignorance on the grounds of harm to others, that is, philosophers who do not deny people's right to ignorance in self-related matters but wish to state that genetic ignorance causes harm to others, and this is one of the most commonly accepted reason for restricting people's freedom. The other line of argument flows from the Kantian view that not even merely self-regarding foolishness (in the eyes of others) should be allowed.  相似文献   
46.
Stimulation of ectodermal organ development by Ectodysplasin-A1   总被引:11,自引:0,他引:11  
Organs developing as ectodermal appendages share similar early morphogenesis and molecular mechanisms. Ectodysplasin, a signaling molecule belonging to the tumor necrosis factor family, and its receptor Edar are required for normal development of several ectodermal organs in humans and mice. We have overexpressed two splice forms of ectodysplasin, Eda-A1 and Eda-A2, binding to Edar and another TNF receptor, Xedar, respectively, under the keratin 14 (K14) promoter in the ectoderm of transgenic mice. Eda-A2 overexpression did not cause a detectable phenotype. On the contrary, overexpression of Eda-A1 resulted in alterations in a variety of ectodermal organs, most notably in extra organs. Hair development was initiated continuously from E14 until birth, and in addition, the transgenic mice had supernumerary teeth and mammary glands, phenotypes not reported previously in transgenic mice. Also, hair composition and structure was abnormal, and the cycling of hairs was altered so that the growth phase (anagen) was prolonged. Both hairs and nails grew longer than normal. Molar teeth were of abnormal shape, and enamel formation was severely disturbed in incisors. Furthermore, sweat gland function was stimulated and sebaceous glands were enlarged. We conclude that ectodysplasin-Edar signaling has several roles in ectodermal organ development controlling their initiation, as well as morphogenesis and differentiation.  相似文献   
47.
An autosomal reciprocal translocation (12;21) was found in five seemingly unrelated families in Finland. Three families had had multiple spontaneous abortions and two families had a child with Down's syndrome. The genealogies of the five families were traced using population registries, and four families were found to have a common ancestor born in 1752. Kinship to the fifth family could not be established but its ancestors were traced back to the same rural parishes as those of the four other families. The translocation segregated at the same frequency as normal chromosomes. A statistically insignificant increase in spontaneous abortions was detected when the matings of translocation carriers were compared with non-carrier matings. The increase may however be clinically significant. These results permit more accurate counselling in these and similar translocation families.  相似文献   
48.
Herbivory is typically intense in marine littoral environments; thus, macrophytes are expected to evolve defenses against grazing. Although putative defenses of macrophytes are widely studied, there is lack of studies demonstrating the main premises of defense adaptations: the consequences of herbivory to macrophytes, genetic variation of defense traits and the costs and benefits of defenses in natural environment. We conducted a factorial experiment, where we manipulated amount of herbivory, growing depth and nutrient availability, and measured resistance to herbivory as well as genetic variation and costs of phlorotannins, putative defensive secondary metabolites, in the brown alga Fucus vesiculosus . Herbivory on algae varied with depth: grazing did not cause losses close to the surface, but, most of the algal production was consumed at the deeper end of the algal belt. The higher the genotypic phlorotannin content the less damage the genotype received implying that phlorotannins acted as a resistance trait. Production of phlorotannins was associated with costs for growth. Consistent with the prediction that the cost of defense will be greatest when resources are limiting, the cost appeared only in the deep end of the algal belt where growth was slowed down. Phlorotannins displayed phenotypic plasticity; the three factors influenced phlorotannins interactively, with the main tendencies of nutrient enrichment decreasing and herbivory and increasing depth increasing phlorotannins. Despite this plasticity, variation of phlorotannins was mainly due to the genotype of algae. These results emphasize the role of herbivory as a selective agent for algal defenses and the importance of genetic variation in the constitutive level of phlorotannins in interactions with natural enemies. The cost of phlorotannins may constrain the evolution of resistance in environments where growth is limited by light availability.  相似文献   
49.
Organs developing as appendages of the ectoderm are initiated from epithelial thickenings called placodes. Their formation is regulated by interactions between the ectoderm and underlying mesenchyme, and several signalling molecules have been implicated as activators or inhibitors of placode formation. Ectodysplasin (Eda) is a unique signalling molecule in the tumour necrosis factor family that, together with its receptor Edar, is necessary for normal development of ectodermal organs both in humans and mice. We have shown previously that overexpression of the Eda-A1 isoform in transgenic mice stimulates the formation of several ectodermal organs. In the present study, we have analysed the formation and morphology of placodes using in vivo and in vitro models in which both the timing and amount of Eda-A1 applied could be varied. The hair and tooth placodes of K14-Eda-A1 transgenic embryos were enlarged, and extra placodes developed from the dental lamina and mammary line. Exposure of embryonic skin to Eda-A1 recombinant protein in vitro stimulated the growth and fusion of placodes. However, it did not accelerate the initiation of the first wave of hair follicles giving rise to the guard hairs. Hence, the function of Eda-A1 appears to be downstream of the primary inductive signal required for placode initiation during skin patterning. Analysis of BrdU incorporation indicated that the formation of the epithelial thickening in early placodes does not involve increased cell proliferation and also that the positive effect of Eda-A1 on placode expansion is not a result of increased cell proliferation. Taken together, our results suggest that Eda-A1 signalling promotes placodal cell fate during early development of ectodermal organs.  相似文献   
50.
Our objective was to detect mass migrations of insects of economic significance by insect traps and a Doppler weather radar. Migrants were sampled by suction traps, tow nets and light traps in the Helsinki region. We used radar to observe the migrating insects, and trajectories to backtrack mass migrations of aphids (Homoptera, Aphididae) in spring 1988. The aphid migrations were clearly observed in trap catches and by radar. The first migration, mainly involving Euceraphis betulae, occurred on 18 May and was tracked back to northern Poland. The second migration, mainly of Rhopalosiphum padi (a serious pest of small-grain cereals), occurred 3 days later and was tracked back to a large area covering Latvia and western Russia south of St Petersburg. The third migration included both E. betulae and R. padi, and took place on 30 May. It originated from Estonia. Neither trap nor radar data provide exact quantitative information on migrations. Trapping efficiency depends strongly on wind speed and insect size. Radar echo intensity is very strongly related to the sizes of insects in the large volume of air measured, and the sizes are not known accurately. Weather data, especially temperature, can be used in predicting the development of aphids, and air-parcel trajectories in estimating the source areas of migrants. These methods for forecasting aphid migrations, combined with radar observations, are useful for warning purposes and to intensify insect trapping. This would contribute to more efficient agricultural pest management. Received: 11 March 2000 / Revised: 24 April 2000 / Accepted: 26 April 2000  相似文献   
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