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61.
Colored biofilms cause problems in paper industry. In this work we used real-time PCR to detect and to quantitate members of the genus Meiothermus from the process samples and end products from 24 machines manufacturing pulp, paper and board in four countries. The results obtained from 200 samples showed the importance of members of the genus Meiothermus as ubiquitous biofoulers in paper machines. This genus was the dominant biofouler in some mills. From ≤104 to 1011 copies of Meiothermus 16S rRNA genes were found per gram of process deposit (wet weight). Meiothermus spp. were found in paper and board products with colored defects and connection between deposit-forming microbes and end-product spots was shown. 16S rRNA gene sequences of 29 biofilm producing bacterial isolates from different mills were determined. Based on sequence data, 25 of the isolates were assigned to the genus Meiothermus, with Meiothermus silvanus and M. ruber as the most frequent species.  相似文献   
62.
A compost facility in northeast Oklahoma is located relatively close to a residential area and is the focus of complaints about smell and concerns about health effects. Several species of Aspergillus have been known to cause health problems, and at least one of these species is dominant in compost. The atmosphere surrounding the compost facility was monitored for 1 year using Burkard spore traps to determine if there was a significant difference in Penicillium/Aspergillus type spores concentration between a test and control site. Samplers were situated 710 m downwind for the test site and 6,085 m upwind at the control site. There was no significant difference in mean concentration of Penicillium/Aspergillus type spores between the two sites (t = 0.576 P > 0.05). The mean concentration of total spores was significantly higher at the upwind control site (t = −7.64, P < 0.01). Wind direction was examined to determine if the compost facility was a possible source for any spikes in concentration. No clear relationship was found between wind direction and mean Penicillium/Aspergillus concentration at the test site, but peak concentrations of Penicillium/Aspergillus seen at the test site were on days when it was downwind from the composting facility. However, these concentrations were no higher than those seen at the control site on other days. If the compost was releasing large amounts of Penicillium/Aspergillus type spores into the atmosphere they were generally diluted to background levels by the time they reached the test site.  相似文献   
63.
Cambrian bivalves from the Middle East are reported here for the first time. They come from early “Middle Cambrian” and latest “Early Cambrian” limestones of the lower Çal Tepe Formation at the type locality (near Seydi?ehir, western Taurides). The majority of the new findings consists of Pojetaia runnegari Jell, 1980, but a few specimens of Fordilla sp. represent the first report of this genus from “Middle Cambrian” strata. Based on a compilation of the hitherto reported, but mostly revised Cambrian bivalves, the today widely accepted taxa are discussed. The genera Pojetaia Jell, 1980 and Fordilla Barrande, 1881 are critically evaluated, and three valid species are included in Pojetaia: P. runnegari Jell, 1980, P. sarhroensis Geyer and Streng, 1998, and—with limitations—P. ostseensis Hinz-Schallreuter, 1995. Fordilla also includes three species: F. troyensis Barrande, 1881, F. sibirica Krasilova, 1977, and F. germanica Elicki, 1994. The Cambrian genera Tuarangia MacKinnon, 1982, Camya Hinz-Schallreuter, 1995, and Arhouriella Geyer and Streng, 1998 most probably belong to the class Bivalvia. Palaeoecologically, the Cambrian bivalves of the Western Perigondwanan shelf seem to occur in a relatively small window of low-energy, subtidal, open-marine, warm-water conditions on a muddy carbonate ramp or platform with reduced sedimentation rate. The frequently interpreted infaunal mode of life of Pojetaia and Fordilla is questioned by observations of similarly organized modern bivalves. The palaeogeographical distribution of Pojetaia and Fordilla is discussed with respect to their early ontogeny and to differences in the recent state of knowledge on shelly fossils from Cambrian carbonate successions of Perigondwana.  相似文献   
64.
In Cupriavidus metallidurans CH34, the proteins CnrX, CnrY, and CnrH regulate the expression of the cnrCBA operon that codes for a cation-efflux pump involved in cobalt and nickel resistance. The periplasmic part of CnrX can be defined as the metal sensor in the signal transduction complex composed of the membrane-bound anti-sigma factor CnrY and the extra-cytoplasmic function sigma factor CnrH. A soluble form of CnrX was overproduced and purified. This protein behaves as a dimer in solution as judged from gel filtration, sedimentation velocity experiments, and NMR. Native crystals diffracting to 2.3 A using synchrotron radiation were obtained using the hanging-drop vapor-diffusion method. They belong to the primitive monoclinic space group P2(1), with unit cell parameters a = 31.87, b = 74.80, c = 93.67 A, beta = 90.107 degrees. NMR data and secondary structure prediction suggest that this protein is essentially formed by helices.  相似文献   
65.
Cordyceps sinensis is widely used as a traditional medicine for treatment of a wide variety of diseases or to maintain health. The immunomodulatory activity of polysaccharides prepared from submerged cultured C. sinensis BCRC36421 was investigated in human peripheral blood. Results demonstrated that Fr. A (exo-polysaccharides, 0.025 ∼ 0.1 mg/ml) induced the production of tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, and IL-10 dose-dependently. Fr. A, as low as 0.025 mg/ml, could significantly augment surface expression of CD11b in monocytes and polymorphonuclear neutrophils. Functional assay revealed that Fr. A (0.05 mg/ml) also elevated phagocytosis in monocytes and PMN. On the other hand, Fr. B (intracellular polysaccharides) only moderately induced TNF-α release, CD11b expression, and phagocytosis at the same concentrations. Our results indicate that the immunomodulatory components of submerged cultured C. sinensis mainly reside in the culture filtrate.  相似文献   
66.
Ionization potential (IP), electron affinity (EA), dipole moment (μ) and electronic polarizability (α) of 1-, 3- and 6-nitrobenzo[a]pyrene isomers (1-NBaP, 3-NBaP, 6-NBaP) were determined by using density functional theory (DFT) and recent semiempirical PM6 methods. Calculated IP value remains almost constant along the series of isomers, while EA value depends on the nitro group position, increasing by ca. 0.2 eV on passing from 6- to 1-NBaP (or 3-NBaP) isomer. Stability, μ and α values decrease in the order 6-NBaP < 1-NBa ∼ 3-NBaP, the largest μ variation being predicted to be 1.5 D (30%) by DFT computations. The results obtained herein are consistent with the observed greater mutagenic activity of 3- and 1-NBaP in comparison to 6-NBaP isomer, suggesting that both binding to enzyme, which depends on electric properties, and reduction process, which is related to EA value may be crucial steps in the mutagenic mechanism of this series of isomers. Figure Structure and dipole moment vector of nitrobenzo[a]pyrene isomers  相似文献   
67.
To achieve higher level expression of Interferon α2b (IFN-α2b) in methylotrophic yeast (Pichia pastoris), a cDNA fragment coding for the mature IFN-α2b was designed and synthesized based on the synonymous codon bias of P. pastoris and optimized G+C content. The synthetic IFN-α2b was inserted into the secreted expression vector pPICZαA, and then integrated into P. pastoris GS115 genome by electroporation. Multi-copy integrants in the Mut+ recombinant P. pastoris strain were screened by high concentrations of Zeocin. 120 hours culturing allowed expression of the IFN-α2b transformant up to 810 mg/L as detected by SDS-PAGE and quantitative methods. In addition, Western blot analysis showed that the recombinant proteins had immunogenicity. The significant antiviral activity of the recombinant IFN-α2b protein was verified by WISH/ VSV system, which was 3.3×105 IU/mL. Foundation items: The National ‘973’ Basic Research Program (2002CB111302); The National Natural Science Foundation of China (30370807)  相似文献   
68.
The detection, attribution and prediction of global and large scale regional change are goals for the Global Observing Systems of the United Nations. Coastal areas are particularly sensitive to global change, but there is a variety of limitations to universal coverage of observations. The coastal module of the Global Terrestrial Observing System (C-GTOS) considers sentinel ecosystems to address these goals for the terrestrial, wetland and freshwater ecosystems of the coast. Sentinel ecosystems for observing systems are a limited number of well understood systems that have substantial datasets and are observed in a sustained fashion, forming an early warning and core system for broader regional and global change. A necessary step in the development of C-GTOS is the examination of current definitions of coastal areas by anticipated users and information providers, and identification of potential coastal networks and sites. We applied the sentinel system framework to the selection of C-GTOS observation sites from several international programs using various global delineations of coastal areas. Delineations were based on the most common definitions of the coast adopted by potential C-GTOS users and information providers, and included mapped areas of various distance from the coastline, coastal areas of low elevation, and a seaward boundary matching the Economic Exclusive Zone (EEZ). Decreases in the number of sites within each international program occurred with each definition marking area closer to the coastline. The Ramsar Convention on Wetlands demonstrates the greatest percentage of coastal sites by any definition. The process of choosing specific sentinel sites for C-GTOS continues from this initial screening, and is the next step towards the development of an in situ site network supporting the observation of global and large scale change. An erratum to this article is available at .  相似文献   
69.
Hai L  Wagner C  Friedt W 《Genetica》2007,130(3):213-225
Genetic diversity in spring bread wheat (T.aestivum L.) was studied in a total of 69 accessions. For this purpose, 52 microsatellite (SSR) markers were used and a total of 406 alleles were detected, of which 182 (44.8%) occurred at a frequency of <5% (rare alleles). The number of alleles per locus ranged from 2 to 14 with an average of 7.81. The largest number of alleles per locus occurred in the B genome (8.65) as␣compared to the A (8.43) and D (5.93) genomes, respectively. The polymorphism index content (PIC) value varied from 0.24 to 0.89 with an average of 0.68. The highest PIC for all accessions was found in the B␣genome (0.71) as compared to the A (0.68) and D␣genomes (0.63). Genetic distance-based method (standard UPGMA clustering) and a model-based method (structure analysis) were used for cluster analysis. The two methods led to analogical results. Analysis of molecular variance (AMOVA) showed that 80.6% of the total variation could be explained by the variance within the geographical groups. In comparison to the diversity detected for all accessions (H e = 0.68), genetic diversity among European spring bread wheats was H e = 0.65. A comparatively higher diversity was observed between wheat varieties from Southern European countries (Austria/Switzerland, Portugal/Spain) corresponding to those from other regions.  相似文献   
70.
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   
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