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Guo Z  Chen P  Ren P  Kuang S  Zhou Z  Li Z  Liu M  Shi D  Xiao Y  Wang X  Zhou R  Jin H  Bi D 《Journal of bacteriology》2011,193(20):5883-5884
Mycoplasma anatis, a member of the class Mollicutes, is the causative agent of a contagious infectious disease of domestic ducklings, wild birds, and eggs. Increasing reports show that coinfection of M. anatis with Escherichia coli results in substantial economic impacts on the duck farms in China. Here, we announce the first genome sequence of M. anatis.  相似文献   
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Emergy evaluation provided global performance indicators that were used to assess the impact of waste exchanges on the sustainability of a sulfuric acid production system (SAPS) and a titanium dioxide production system (TDPS) in Pan-zhi-hua City, China. Impact of emissions was quantified in terms of emergy and integrated into the classic emergy-based indicators. Results show that waste exchanges improve the sustainability of the two systems, although the SAPS benefits more from the waste exchanges than the TDPS from an economic perspective however, the impact of emissions reduces their sustainability to some degree. This study creates awareness and brings new insight to the gains achieved with resource recovery from waste in the interrelated industrial systems, which is derived from the mutualism relationship existing in natural ecosystems. Finally, this paper puts forward some corresponding suggestions.  相似文献   
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Electrogenerated chemiluminescence (ECL) of a ruthenium complex polymer modified carbon paste electrode and its analytical applications were investigated. The ruthenium complex polymer was prepared using bis(2,2‐bipyridine) (4,4‐dicarboxy‐2,2‐bipyridine) ruthenium(II). The ECL behaviours of ruthenium complex polymer modified carbon paste electrode were investigated in the absence and presence of tripropylamine (TPA). The modified carbon paste electrode exhibited long‐term stability and fine reproducibility. The ECL intensity of the modified carbon paste electrode was linear with the concentration of TPA in the range 2.0 × 10–6–3.8 × 10–3 mol/L, with a detection limit (S:N = 3) of 6 × 10–7 mol/L. It was also found that raceanisodamine could enhance the ECL intensity of the modified electrode. The ECL intensity of the modified carbon paste electrode was linear with the concentration of raceanisodamine in the range 1.1 × 10–5–6.0 × 10–4 mol/L, with a detection limit (S:N = 3) of 6 × 10–6 mol/L. This work demonstrates that the entrapment of ruthenium complex in a highly cross‐linked polymer is a promising approach to construct an ECL modified electrode with long‐term stability and fine reproducibility. The modified electrode designed has a potential application in the ECL detector. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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In order to identify the lower limb movements accurately and quickly, a recognition method based on extreme learning machine (ELM) is proposed. The recognizing target set is constructed by decomposing the daily actions into different segments. To get the recognition accuracy of seven movements based on the surface electromyography, the recognition feature vector space is established by integrating short-time statistical characteristics under time domain, and locally linear embedding algorithm is used to reduce the computational complexity and improve robustness of algorithm. Compared with BP, the overall recognition accuracy for each subject in the best dimension with ELM is above 95%.  相似文献   
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A genetic modification scheme was designed for Aspergillus oryzae A-4, a natural cellulosic lipids producer, to enhance its lipid production from biomass by putting the spotlight on improving cellulase secretion. Four cellulase genes were separately expressed in A-4 under the control of hlyA promoter, with the help of the successful development of a chromosomal genetic manipulation system. Comparison of cellulase activities of PCR-positive transformants showed that these transformants integrated with celA gene and with celC gene had significantly (p<0.05) higher average FPAase activities than those strains integrated with celB gene and with celD gene. Through the assessment of cellulosic lipids accumulating abilities, celA transformant A2-2 and celC transformant D1-B1 were isolated as promising candidates, which could yield 101%–133% and 35.22%–59.57% higher amount of lipids than the reference strain A-4 (WT) under submerged (SmF) conditions and solid-state (SSF) conditions, respectively. Variability in metabolism associated to the introduction of cellulase gene in A2-2 and D1-B1 was subsequently investigated. It was noted that cellulase expression repressed biomass formation but enhanced lipid accumulation; whereas the inhibitory effect on cell growth would be shielded during cellulosic lipids production owing to the essential role of cellulase in substrate utilization. Different metabolic profiles also existed between A2-2 and D1-B1, which could be attributed to not only different transgene but also biological impacts of different integration. Overall, both simultaneous saccharification and lipid accumulation were enhanced in A2-2 and D1-B1, resulting in efficient conversion of cellulose into lipids. A regulation of cellulase secretion in natural cellulosic lipids producers could be a possible strategy to enhance its lipid production from lignocellulosic biomass.  相似文献   
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Shen Z  Ma J  Liu Y  Jiao C  Li M  Zhang Y 《Chirality》2005,17(9):556-558
beta-Cyclodextrin-immobilized (4S)-phenoxy-(S)-proline was prepared conveniently by simply heating the amino acid and beta-cyclodextrin in ethanol-water (1/1, v/v) and removal of the solvent. This proved to be an efficient catalyst for direct asymmetric aldol reactions, and the catalyst could be recycled four times without loss of enantioselectivity.  相似文献   
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