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排序方式: 共有206条查询结果,搜索用时 15 毫秒
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Chinese life cycle impact assessment factors 总被引:5,自引:0,他引:5
IntroductionLifecycleassessment(LCA)isanenvironmentalmanagementtoolthatisusedtoexamineandevaluatetheenvironmentalimpactsassociatedwiththeexistenceofproducts(Jensen,1998;Weidema,1997;Wenzel,1997).ThefocusofLCAisontheentirelifecycleoftheproduct,i.e.fromtheextracti… 相似文献
3.
Three different types of chromosome 12 inversion were seen in 15 individuals out of 44 individuals examined in one 8 generation family. Type 1: a pericentric inversion inv(12) (p112; q131) was found in 7 individuals and twice at prenatal diagnosis. Type 2: a paracentric inversion inv(12) (p123; p131) was seen in two individuals. Two individuals carried both inversion chromosomes, namely type 1 and type 2. The two inversion chromosomes were transmitted from each of the parents. Type 3: a double pericentric and paracentric inversion (type 3) inv(12) (p123; p131) (p112; q131) was observed in the daughter of one of the carriers of type 1 and 2 inversions and again at prenatal diagnosis in her son. The double inversion most likely arose through crossing-over in between the two inversion loops. A balanced translocation t(7; 13) and the inversion type 1 was observed in one individual, who transmitted the translocation only to an offspring. The frequency of inversions in amniotic fluid cells observed in our laboratory was 1·9 per cent. The clinical implications of these findings are discussed. 相似文献
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Anders Malmendal Jesper Givskov Sørensen Johannes Overgaard Martin Holmstrup Niels Chr. Nielsen Volker Loeschcke 《Die Naturwissenschaften》2013,100(5):417-427
We investigated the global metabolite response to artificial selection for tolerance to stressful conditions such as cold, heat, starvation, and desiccation, and for longevity in Drosophila melanogaster. Our findings were compared to data from other levels of biological organization, including gene expression, physiological traits, and organismal stress tolerance phenotype. Overall, we found that selection for environmental stress tolerance changes the metabolomic 1H NMR fingerprint largely in a similar manner independent of the trait selected for, indicating that experimental evolution led to a general stress selection response at the metabolomic level. Integrative analyses across data sets showed little similarity when general correlations between selection effects at the level of the metabolome and gene expression were compared. This is likely due to the fact that the changes caused by these selection regimes were rather mild and/or that the dominating determinants for gene expression and metabolite levels were different. However, expression of a number of genes was correlated with the metabolite data. Many of the identified genes were general stress response genes that are down-regulated in response to selection for some of the stresses in this study. Overall, the results illustrate that selection markedly alters the metabolite profile and that the coupling between different levels of biological organization indeed is present though not very strong for stress selection at this level. The results highlight the extreme complexity of environmental stress adaptation and the difficulty of extrapolating and interpreting responses across levels of biological organization. 相似文献
6.
Pietro K. Maruyama Genilda M. Oliveira Carolina Ferreira Bo Dalsgaard Paulo E. Oliveira 《Die Naturwissenschaften》2013,100(11):1061-1068
Generalization prevails in flower–animal interactions, and although animal visitors are not equally effective pollinators, most interactions likely represent an important energy intake for the animal visitor. Hummingbirds are nectar-feeding specialists, and many tropical plants are specialized toward hummingbird-pollination. In spite of this, especially in dry and seasonal tropical habitats, hummingbirds may often rely on non-ornithophilous plants to meet their energy requirements. However, quantitative studies evaluating the relative importance of ornithophilous vs. non-ornithophilous plants for hummingbirds in these areas are scarce. We here studied the availability and use of floral resources by hummingbirds in two different areas of the Cerrado, the seasonal savannas in Central Brazil. Roughly half the hummingbird visited plant species were non-ornithophilous, and these contributed greatly to increase the overall nectar availability. We showed that mean nectar offer, at the transect scale, was the only parameter related to hummingbird visitation frequency, more so than nectar offer at single flowers and at the plant scale, or pollination syndrome. Centrality indices, calculated using hummingbird–plant networks, showed that ornithophilous and non-ornithophilous plants have similar importance for network cohesion. How this foraging behaviour affects reproduction of non-ornithophilous plants remains largely unexplored and is probably case specific, however, we suggest that the additional energy provided by non-ornithophilous plants may facilitate reproduction of truly ornithophilous flowers by attracting and maintaining hummingbirds in the area. This may promote asymmetric hummingbird–plant associations, i.e., pollination depends on floral traits adapted to hummingbird morphology, but hummingbird visitation is determined more by the energetic "reward" than by pollination syndromes. 相似文献
7.
Johan Östberg Tim Delshammar Björn Wiström Anders Busse Nielsen 《Environmental management》2013,51(3):694-708
Tree inventories are expensive to conduct and update, so every inventory carried out must be maximized. However, increasing the number of constituent parameters increases the cost of performing and updating the inventory, illustrating the need for careful parameter selection. This article reports the results of a systematic expert rating of tree inventories aiming to quantify the relative importance of each parameter. Using the Delphi method, panels comprising city officials, arborists, and academics rated a total of 148 parameters. The total mean score, the top ranking parameters, which can serve as a guide for decision-making at practical level and for standardization of tree inventories, were: Scientific name of the tree species and genera, Vitality, Coordinates, Hazard class, and Identification number. The study also examined whether the different responsibilities and usage of urban tree databases among organizations and people engaged in urban tree inventories affected their prioritization. The results revealed noticeable dissimilarities in the ranking of parameters between the panels, underlining the need for collaboration between the research community and those commissioning, administrating, and conducting inventories. Only by applying such a transdisciplinary approach to parameter selection can urban tree inventories be strengthened and made more relevant. 相似文献
8.
Johantgen M Trinkoff A Gray-Siracusa K Muntaner C Nielsen K 《Journal of Safety Research》2004,35(3):309-315
PROBLEM: Administrative data from states have the potential to capture broader representation of worker injury, facilitating examination of trends, correlates, and patterns. While many states use their workers' compensation (WC) data to document frequency and type of injury, few conduct in-depth examinations of patterns of injury and other etiologies. Administrative data are generally an untapped resource. METHOD: Comparisons are made among four state databases used in a study linking worker injuries and patient outcomes in hospitals and nursing homes. RESULTS: Worker injury data varies in terms of inclusion criteria, variables, and coding schemes used. Linkages to organizational level characteristics can be difficult. CONCLUSIONS: Despite limitations, data can be used to study injury patterns and etiologies. Users must be knowledgeable and recognize how database characteristics may influence results. 相似文献
9.
Kollist-Siigur K Nielsen T Grøn C Hansen PE Helweg C Jonassen KE Jørgensen O Kirso U 《Journal of environmental quality》2001,30(2):526-537
Two different humic acids (HA) and a fulvic acid (FA) were chemically immobilized to a high performance liquid chromatography (HPLC) silica column material. The immobilization was performed by binding amino groups in HA/FA to the free aldehyde group in glutardialdehyde attached to the silica gel. The HPLC column materials were compared with a blank column material made by applying the same procedure but without immobilizing HA or FA. Also, a column was made by binding carbonyl groups in HA to amino groups attached to the silica gel. The humic substances were selected to secure appropriate variation of their structural features. The retention factors of 45 polycyclic aromatic compounds (PAC) to the four columns were determined by HPLC. The advantage of the technique is a large number of compounds can easily be studied. The binding procedure does not appear to cause a drastic selection between the HA molecules. The k' values obtained for the two Aldrich HA columns agree in general reasonably. The retention or sorption of the compounds increased with the size of the PAC and the number of lipophilic substituents, but decreased when polar substituents were present. The PAC retention was much stronger to the two HA columns than to the FA and blank column, both for hydrophobic polycyclic aromatic hydrocarbons (PAH) and the polar PAC. Other factors impacting the PAC binding may be specific interactions with HA and the ionic strength of the aqueous phase. The technique has been applied to do direct determinations of Koc. 相似文献
10.
Annika Porsborg Nielsen Jesper Lassen Peter Sandøe 《Journal of Agricultural and Environmental Ethics》2007,20(1):13-35
Over recent decades, public participation in technology assessment has spread internationally as an attempt to overcome or
prevent societal conflicts over controversial technologies. One outcome of this new surge in public consultation initiatives
has been the increased use of participatory consensus conferences in a number of countries. Existing evaluations of consensus
conferences tend to focus on the modes of organization, as well as the outcomes, both procedural and substantial, of the conferences
they examine. Such evaluations seem to rest on the assumption that this type of procedure has universally agreed goals and
meanings, and that therefore consensus conferences can readily be interpreted and applied across national boundaries. This
article challenges this approach to consensus conferences. The core of the article is a study of national differences in ideas
about what constitutes legitimate goals for participatory arrangements. The study looks at three consensus conferences on
GMOs, which took place in France, Norway, and Denmark. Drawing on this study, the article discusses the ways in which interpretations
of the concept of participation; the value attributed to lay knowledge vs. technical expertise; as well as ideas about the
role of the layperson, are all questions that prompt entirely different answers from country to country. Further, the article
analyses these national differences within a theoretical framework of notions of democratic legitimacy. 相似文献