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1.
  1. Birds colliding with turbine rotor blades is a well‐known negative consequence of wind‐power plants. However, there has been far less attention to the risk of birds colliding with the turbine towers, and how to mitigate this risk.
  2. Based on data from the Smøla wind‐power plant in Central Norway, it seems highly likely that willow ptarmigan (the only gallinaceous species found on the island) is prone to collide with turbine towers. By employing a BACI‐approach, we tested if painting the lower parts of turbine towers black would reduce the collision risk.
  3. Overall, there was a 48% reduction in the number of recorded ptarmigan carcasses per search at painted turbines relative to neighboring control (unpainted) ones, with significant variation both within and between years.
  4. Using contrast painting to the turbine towers resulted in significantly reduced number of ptarmigan carcasses found, emphasizing the effectiveness of such a relatively simple mitigation measure.
  相似文献   
2.
Bacterial Metabolism of 2,6-Xylenol   总被引:3,自引:3,他引:0       下载免费PDF全文
Strain DM1, a Mycobacterium sp. that utilizes 2,6-xylenol, 2,3,6-trimethylphenol, and o-cresol as sources of carbon and energy, was isolated. Intact cells of Mycobacterium strain DM1 grown with 2,6-xylenol cooxidized 2,4,6-trimethylphenol to 2,4,6-trimethylresorcinol. 4-Chloro-3,5-dimethylphenol prevents 2,6-xylenol from being totally degraded; it was quantitatively converted to 2,6-dimethylhydroquinone by resting cells. 2,6-Dimethylhydroquinone, citraconate, and an unidentified metabolite were detected as products of 2,6-xylenol oxidation in cells that were partially inactivated by EDTA. Under oxygen limitation, 2,6-dimethylhy-droquinone, citraconate, and an unidentified metabolite were released during 2,6-xylenol turnover by resting cells. Cell extracts of 2,6-xylenol-grown cells contained a 2,6-dimethylhydroquinone-converting enzyme. When supplemented with NADH, cell extracts catalyzed the reduction of 2,6-dimethyl-3-hydroxyquinone to 2,6-dimethyl-3-hydroxyhydroquinone. Since a citraconase was also demonstrated in cell extracts, a new metabolic pathway with 2,6-dimethyl-3-hydroxyhydroquinone as the ring fission substrate is proposed.  相似文献   
3.
Two isoprene (2-methyl-1,3-butadiene) utilizing bacteria, Alcaligenes denitrificans ssp. xylosoxidans JE 75 and Rhodococcus erythropolis JE 77, were identified as highly efficient cooxidizers of TCE, cis- and transdichloroethene, 1,1-dichloroethene and vinylchloride. Isoprene grown cells eliminate chloride from TCE in stoichiometric amounts and tolerate high concentrations of TCE.  相似文献   
4.
Human major histocompatibility complex (HLA) cDNA probes were used to analyze the restriction fragment length polymorphism (RFLP) of the DLA-D region in dogs. Genomic DNA from peripheral blood leucocytes of 23 unrelated DLA-D-homozygous dogs representing nine DLA-D types (defined by mixed leucocyte reaction) was digested with restriction enzymes (Bam HI, Eco RI, Hind III, Pvu II, Taq I, Rsa I, Msp I, Pst I, and Bgl II), separated by agarose gel electrophoresis, and transferred onto Biotrace membrane. The Southern blots were successively hybridized with radiolabeled HLA cDNA probes corresponding to DR, DQ, DP, and DO beta genes. The autoradiograms for all nine enzyme digests displayed multiple bands with the DRb, DQb, and DPb probes while the DOb probe hybridized with one to two bands. The RFLP patterns were highly polymorphic but consistent within each DLA-D type. Standard RFLP patterns were established for nine DLA-D types which could be discriminated from each other by using two enzymes (Rsa I and Pst I) and the HLA-DPb probe. Cluster analysis of the polymorphic restriction fragments detected by the DRb probe revealed four closely related supertypic groups or DLA-DR families: Dw3+Dw4+D1, Dw8+D10, D7+D16+D9, and Dw1. This study provides the basis for DLA-D genotyping at a population level by RFLP analysis. These results also suggest that the genetic organization of the DLA-D region may closely resemble that of the HLA complex.  相似文献   
5.
Jarl, C. I., Ljungberg, U. K. and Bornman, C. H. 1988. Correction of chlorophyll-defective male-sterile winter oilseed rape ( Brassica napus ) through organelle exchange: Characterization of the chlorophyll deficiency. - Physiol. Plant. 72: 505–510.
As is known, the introduction of male-sterile Raphanus sativus L. cytoplasm into Brassica napus L. results in male-sterile oilseed rape plants, which display a temperature-related chlorophyll defect. The influences of temperature and irradiance on this defect were investigated. Compared to a line of normal (green phenotype) male-fertile oilseed rape, the male-sterile line had reduced chlorophyll content, fewer chloroplasts per cell, an altered ultrastructure of the chloroplasts and reduced activities of both photosystems, although the relative amounts of the photosystems and the chlorophyll a/b ratio were similar. The lower activity of the photosystems is explained by a decreased functional antennae size and a reduced efficiency in the interactions between the nuclear-encoded light-harvesting proteins and the reaction centres coded for by the plastome. Some thylakoid polypeptides differed in proportion between the male-fertile line with green phenotype and the male-sterile line with chlorotic phenotype. Characters, in which the two lines exhibited differences, are ascribed to difficulties in molecular communication between the oilseed rape nucleus and the radish cytoplasm, which are combined in the deficient male-sterile line.  相似文献   
6.
A 6-aminonaphthalene-2-sulfonic acid (6A2NS)-degrading mixed bacterial community was isolated from a sample of river Elbe water. The complete degradation of this xenobiotic compound may be described by a mutualistic interaction of two Pseudomonas strains isolated from this culture. One strain, BN6, could also grow on 6A2NS in monoculture, however, with accumulation of black polymers. This organism effected the initial conversion of 6A2NS into 5-aminosalicylate (5AS) through regioselective attack of the naphthalene skeleton in the 1,2-position. 5AS was totally degraded by another member of the community, strain BN9. After prolonged adaptation of strain BN6 to growth on 6A2NS, this organism readily converted all naphthalene-2-sulfonates with OH- or NH2-substituents in the 5-, 6-, 7-, or 8-position. The corresponding hydroxy- or aminosalicylates were excreted in stoichiometric amounts, with the exception that the metabolite from 5A2NS oxidation was not identical with 6AS.  相似文献   
7.
DNA fragments containing the xylD and xylL genes of TOL plasmid pWW0 -161 of Pseudomonas putida, which code for the catabolic enzymes toluate 1,2-dioxygenase and dihydrodihydroxybenzoic acid dehydrogenase, respectively, and the nahG gene of the NAH plasmid NAH7 , which codes for salicylate hydroxylase, were cloned in pBR322 vector plasmid. Deletion and insertion mutagenesis were used to localize these genes with respect to crucial endonuclease cleavage sites. The pBR322-based plasmids were ligated to the broad host range cloning vector pKT231 , or derivatives of it, and the hybrid plasmids were introduced into Pseudomonas sp. B13( WR1 ), a bacterium able to degrade 3-chlorobenzoate but not 4-chlorobenzoate, 3,5- dichlorobenzoate , salicylate, or chlorosalicylates . The cloned xylD gene expanded the catabolic range of WR1 to include 4-chlorobenzoate, whereas the cloned xylD - xylL genes enabled the isolation of derivatives of WR1 that degraded 3-chlorobenzoate, 4-chlorobenzoate, and 3,5- dichlorobenzoate . The cloned nahG gene extended the catabolic range of WR1 to include salicylate and 3-, 4-, and 5- chlorosalicylate .  相似文献   
8.
The hybrid strain Pseudomonas sp. WR4016 was subcultivated with increasing concentrations of 5-chlorosalicylate (510 mM) as sole carbon source over a period of 9 months. At intervals of approximately 3 months derivative strains WR4017, WR4018 and WR4019 were isolated which exhibited higher growth rates and increased substrate tolerance. Comparative analysis of the turnover rates of the key enzymes in chlorosalicylate degradation showed that the adaptation process did not result from structural modifications of these proteins. Instead, balanced over-production of the salicylate hydroxylase and catechol 1,2-dioxygenase prevented the accumulation of toxic chlorocatechols and accounted for the reduction of the doubling times with 4- or 5-chlorosalicylate. A comparative analysis of a genetically engineered chlorosalicylate degrader PL300-1 showed similar regulatory patterns as the most advanced isolate WR4019 from the adaptation series.  相似文献   
9.
Isolation and characterization of a 3-chlorobenzoate degrading pseudomonad   总被引:76,自引:0,他引:76  
A pseudomonad has been isolated from sewage, which can utilize 3-chlorobenzoic acid as a sole carbon source. In cells grown on benzoate the enzymes of the -ketoadipic acid pathway are present. Considerable enzymic activities for chlorinated substrates were found in benzoate grown cells only for the oxygenation of 3-chlorobenzoate and the dehydrogenation of 3- and 5-chloro-3,5-cyclohexadiene-1,2-diol-1-carboxylic acid. 3-Chlorobenzoate grown cells show additional high activities for the turnover of 3- and 4-chlorocatechols and chloromuconic acids.Abbreviations Used DHB (-)-3,5-cyclohexadiene-1,2-diol-1-carboxylic acid (derived from the trivial name, dihydrodihydroxybenzoate) - 3- and 5-Cl-DHB correspondingly 3- and 5-chloro-3,5-cyclohexadiene-1,2-diol-1-carboxylic acid  相似文献   
10.
Observations on freeze-fractured membranes of a Trypanosome   总被引:1,自引:0,他引:1  
Pure preparations of Trypanosoma brucei, free from plasma and cellular components were isolated from rat blood, and concentrated into loose pellets by low-speed centrifugation. Pellets were either processed for thin sectioning as a control for general morphology, or glycerol-treated after glutaraldehyde fixation for preparation of freeze-fracture replicas. Concentration of cells of 50,000–100,000/mm2 of sectioned or fractured surface facilitated identification of fracture faces of the cell body, invaginated flagellar pocket and flagellum. Particle distribution and A and B faces of these regions of the cell are described. A collar of B face particles occurs around the neck of the flagellar pocket, possibly associated with a junction controlling ingress of ingested materials to coated vesicles formed along the membrane defining the pocket. A and B faces of the flagellum and adjoining surface of the cell body have shown that the only intra-membrane specialization corresponding to the miniature ‘maculae adherentes’ described previously in thin sections is probably an uninterrupted series of small clusters (3–6) of 80 Å particles on the A face of the flagellar membrane. It is proposed that these arrays represent attachment points for strands linking the axoneme and paraxial rod to the flagellar surface, and are not directly concerned with the physical adhesion of the flagellum to the cell body surface—a linkage that appears to be established within the extracellular gap between these apposed surfaces of the cell. The potential use of freeze-etching in further study of the external antigens of the infective cell is discussed.  相似文献   
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