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31.
Data availability and data quality are still critical factors for successful LCA work. The SETAC-Europe LCA Working Group ‘Data Availability and Data Quality’ has therefore focused on ongoing developments toward a common data exchange format, public databases and accepted quality measures to find science-based solutions than can be widely accepted. A necessary prerequisite for the free flow and exchange of life cycle inventory (LCI) data and the comparability of LCIs is the consistent definition, nomenclature, and use of inventory parameters. This is the main subject of the subgroup ‘Recommended List of Exchanges’ that presents its results and findings here:
•  Rigid parameter lists for LCIs are not practical; especially, compulsory lists of measurements for all inventories are counterproductive. Instead, practitioners should be obliged to give the rationale for their scientific choice of selected and omitted parameters. The standardized (not: mandatory!) parameter list established by the subgroup can help to facilitate this.
•  The standardized nomenclature of LCI parameters and the standardized list of measurement bases (units) for these parameters need not be appliedinternally (e.g. in LCA software), but should be adhered to inexternal communications (data for publication and exchange). Deviations need to be clearly stated.
•  Sum parameters may or may not overlap - misinterpretations in either direction introduce a bias of unknown significance in the subsequent life cycle impact assessments (LCIA). The only person who can discriminate unambiguously is the practitioner who measures or calculates such values. Therefore, a clear statement of independence or overlap is necessary for every sum parameter reported.
•  Sum parameters should be only used when the group of emissions as such is measured. Individually measured emission parameters should not be hidden in group or sum parameters.
•  Problematic substances (such as carcinogens, ozone depleting agents and the like) maynever be obscured in group emissions (together with less harmful substances or with substances of different environmental impact), butmust be determined and reported individually, as mentioned in paragraph 3.3 of this article.
•  Mass and energy balances should be carried out on a unit process level. Mass balances should be done on the level of the entire mass flow in a process as well as on the level of individual chemical elements.
•  Whenever possible, practitioners should try to fill data gaps with their knowledge of analogous processes, environmental expert judgements, mass balance calculations, worst case assumptions or similar estimation procedures.
  相似文献   
32.
The phytohormones ethylene and auxin regulate many important processes in plants, including cell differentiation, cell expansion, and responses to abiotic stresses. These hormones also play important roles in many plant-pathogen interactions, including regulation of plant defense responses and symptom development. Sedentary plant-parasitic nematodes, which require the formation of a complex feeding site within the host root, are among the world’s most destructive plant pathogens. Nematode-induced feeding sites show dramatic changes in host cell morphology and gene expression. These changes are likely mediated, at least in part, by phytohormones. In the present review, current knowledge of the roles of ethylene and auxin will be explored in two main areas: the specific role of phytohormones in mediating feeding site development by plant-parasitic nematodes and the general role of phytohormones in affecting the ability of parasitic nematodes to cause disease. Published in Russian in Fiziologiya Rastenii, 2009, Vol. 56, No. 1, pp. 3–7. This article was presented in original.  相似文献   
33.
Genomic imprinting is an epigenetic mechanism controlling parental-origin-specific gene expression. Perturbing the parental origin of the distal portion of mouse chromosome 12 causes alterations in the dosage of imprinted genes resulting in embryonic lethality and developmental abnormalities of both embryo and placenta. A 1 Mb imprinted domain identified on distal chromosome 12 contains three paternally expressed protein-coding genes and multiple non-coding RNA genes, including snoRNAs and microRNAs, expressed from the maternally inherited chromosome. An intergenic, parental-origin-specific differentially methylated region, the IG-DMR, which is unmethylated on the maternally inherited chromosome, is necessary for the repression of the paternally expressed protein-coding genes and for activation of the maternally expressed non-coding RNAs: its absence causes the maternal chromosome to behave like the paternally inherited one. Here, we characterise the developmental consequences of this epigenotype switch and compare these with phenotypes associated with paternal uniparental disomy of mouse chromosome 12. The results show that the embryonic defects described for uniparental disomy embryos can be attributed to this one cluster of imprinted genes on distal chromosome 12 and that these defects alone, and not the mutant placenta, can cause prenatal lethality. In the placenta, the absence of the IG-DMR has no phenotypic consequence. Loss of repression of the protein-coding genes occurs but the non-coding RNAs are not repressed on the maternally inherited chromosome. This indicates that the mechanism of action of the IG-DMR is different in the embryo and the placenta and suggests that the epigenetic control of imprinting differs in these two lineages.  相似文献   
34.
Our aim was to estimate the population of emperor penguins (Aptenodytes fosteri) using a single synoptic survey. We examined the whole continental coastline of Antarctica using a combination of medium resolution and Very High Resolution (VHR) satellite imagery to identify emperor penguin colony locations. Where colonies were identified, VHR imagery was obtained in the 2009 breeding season. The remotely-sensed images were then analysed using a supervised classification method to separate penguins from snow, shadow and guano. Actual counts of penguins from eleven ground truthing sites were used to convert these classified areas into numbers of penguins using a robust regression algorithm.We found four new colonies and confirmed the location of three previously suspected sites giving a total number of emperor penguin breeding colonies of 46. We estimated the breeding population of emperor penguins at each colony during 2009 and provide a population estimate of ~238,000 breeding pairs (compared with the last previously published count of 135,000-175,000 pairs). Based on published values of the relationship between breeders and non-breeders, this translates to a total population of ~595,000 adult birds.There is a growing consensus in the literature that global and regional emperor penguin populations will be affected by changing climate, a driver thought to be critical to their future survival. However, a complete understanding is severely limited by the lack of detailed knowledge about much of their ecology, and importantly a poor understanding of their total breeding population. To address the second of these issues, our work now provides a comprehensive estimate of the total breeding population that can be used in future population models and will provide a baseline for long-term research.  相似文献   
35.
In Saccharomyces cerevisiae, the Yap family of basic leucine zipper (bZip) proteins contains eight members. The Yap family proteins are implicated in a variety of stress responses; among these proteins, Yap1 acts as a major regulator of oxidative stress responses. However, the functional roles of the remaining Yap family members are poorly understood. To elucidate the function of Yap2, we mined candidate target genes of Yap2 by proteomic analysis. Among the identified genes, FRM2 was previously identified as a target gene of Yap2, which confirmed the validity of our screening method. YNL134C and YDL124W were also identified as candidate Yap2 target genes. These genes were upregulated in strains overexpressing Yap2 and possess Yap2 target sequences in their promoter regions. Furthermore, chromatin immunoprecipitation assays showed that YNL134C and YDL124W have Yap2 binding motif. These data will help to elucidate the functional role of Yap2.  相似文献   
36.
Summary

The vegetation of a small spoil heap at Jerah mine near Stirling was classified as species-rich acid grassland, an open barren-soil community with a high frequency of the moss Pohlia nutans, and a group which showed intermediate characteristics. Copper was present in the soil in potentially toxic concentrations and when the vegetation data were ordinated the axes showed highly significant correlations with soil copper and loss-on-ignition. The results suggest that copper is a major determinant of the spoil-heap vegetation, and contrast sharply with those reported for the Burn of Sorrow mine, a site with many superficial similarities.  相似文献   
37.
38.
The diversity of class II major histocompatibility complex (MHC) loci was investigated in the brushtail possum, an important marsupial pest species in New Zealand. Immunocontraception, a form of fertility control that generates an autoimmune response, is being developed as a population control method for the possum. Because the immune response is partly under genetic control, an understanding of immunogenetics in possum will be crucial to the development of immunocontraceptive vaccines. MHC molecules are critical in the vertebrate immune response. Class II MHC molecules bind and present exogenously derived peptides to T lymphocytes and may be important in the presentation of immunocontraceptives. We used polymerase chain reaction primers designed to amplify the peptide binding region of possum class II MHC genes to isolate sequences from 49 animals. We have previously described 19 novel alleles from the DAB locus in the possum (Holland et al., Immunogenetics 60:449–460, 2008). Here, we report on another 11 novel alleles isolated from possum DAB, making this the most diverse marsupial locus described so far. This high level of diversity indicates that DAB is an important MHC locus in the possum and will need to be taken into account in the design of immunocontraceptive vaccines.  相似文献   
39.
The Myxococcus xanthus gene, pkn9 , encodes a protein that contains significant homology with eukaryotic Ser/Thr protein kinases. The pkn9 gene was singled out of a previously identified family of kinase genes by amplification techniques that displayed differences in kinase gene expression during selected periods of the M. xanthus life cycle. Pkn9 was constitutively expressed during vegetative growth and upregulated during the aggregation stage of early development. It consists of 589 amino acids, and its N-terminal 394 residues show 38% identity with both Pkn1 and Pkn2 of M. xanthus . This region also shows 29, 25 and 29% identity with myosin light-chain kinase, protein kinase C, and cAMP-dependent protein kinase, respectively. A 22-residue hydrophobic transmembrane domain separates the kinase domain from the 173-residue C-terminal domain that resides on the outside of the inner membrane. The C-terminal domain contains two sets of tandem repeats of 13 and 10 residues which have no known function. When expressed in Escherichia coli under the T7 promoter, Pkn9 was found to be phosphorylated on serine and threonine residues. Disruption of the pkn9 kinase catalytic subdomains I–III by the insertion of a kanamycin-resistance gene resulted in slightly delayed, smaller and more-crowded fruiting bodies, while spore formation was normal. Total deletion of the pkn9 gene caused severely reduced progression through development resulting in light loose mounds that become slightly more compact over time. Development progressed further at the centre than at the edge of the spot, and spore formation was significantly reduced. Two-dimensional gel analysis revealed that both the disruption and the deletion of pkn9 prevented the expression of five membrane proteins (KREP9-1-4). These results suggest that the loss of Pkn9 kinase activity caused altered fruiting-body formation, the absence of the KREP9 proteins in the membrane, and reduced spore production.  相似文献   
40.
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