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Some Universal Characteristics of Intertidal Bacterial Diversity as Revealed by 16S rRNA Gene-Based PCR Clone Analysis

  • Shuang, J.L.;Liu, C.H.;An, S.Q.;Xing, Y.;Zheng, G.Q.;Shen, Y.F.
    • Journal of Microbiology and Biotechnology
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    • v.16 no.12
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    • pp.1882-1889
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    • 2006
  • A 16S rDNA clone library was generated to investigate the bacterial diversity in intertidal sediment from the coast of the Yellow Sea, P. R. China. A total of 102 clones were sequenced and grouped into 73 OTUs using a phylogenetic approach. The sequenced clones fell into 11 bacterial lineages: Proteobacteria, Bacteroidetes, Planctomycetes, Chloroflexi, Acidobacteria, Actinobacteria, Firmicutes, Spirochaetes, and candidate divisions of BRCl, OP3, and OP1l. Based on a phylogenetic analysis of these bacteria, together with the ten most closely related sequences deposited in the GenBank, it was concluded that intertidal bacteria are most likely derived from marine bacteria with a remarkable diversity, and some are particularly abundant in intertidal sediment.

Effect of ACADL on the differentiation of goat subcutaneous adipocyte

  • A Li;YY Li;QB Wuqie;X Li;H Zhang;Y Wang;YL Wang;JJ Zhu;YQ Lin
    • Animal Bioscience
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    • v.36 no.6
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    • pp.829-839
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    • 2023
  • Objective: The aim of this study was to clone the mRNA sequence of the Acyl-CoA dehydrogenase long chain (ACADL) gene of goats and explore the effect of ACADL on the differentiation of subcutaneous fat cells on this basis. Methods: We obtained the ACADL gene of goats by cloning and used quantitative real-time polymerase chain reaction (qPCR) to detect the ACADL expression patterns of different goat tissues and subcutaneous fat cells at different lipid induction stages. In addition, we transfect intramuscular and subcutaneous adipocytes separately by constructing overexpressed ACADL vectors and synthesizing Si-ACADL; finally, we observed the changes in oil red stained cell levels under the microscope, and qPCR detected changes in mRNA levels. Results: The results showed goat ACADL gene expressed in sebum fat. During adipocyte differentiation, ACADL gradually increased from 0 to 24 h of culture, and decreased. Overexpression of ACADL promoted differentiation of subcutaneous adipocytes in goat and inhibited their differentiation after interference. Conclusion: So, we infer ACADL may have an important role in positive regulating the differentiation process in goat subcutaneous adipocytes. This study will provide basic data for further study of the role of ACADL in goat subcutaneous adipocyte differentiation and lays the foundation for final elucidating of its molecular mechanisms in regulating subcutaneous fat deposition in goats.

Influence of "Historical Effects" on the Rheological Properties of a Polyacrylonitrile Copolymer Solution

  • Cheng, Yumin;Zhang, Huibo;Zhang, Shuangkun;Liu, Weiwei;Wang, Jing;Cheng, Run;Ryu, SeungKon;Jin, Riguang
    • Carbon letters
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    • v.14 no.1
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    • pp.45-50
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    • 2013
  • Polyacrylonitrile (PAN) copolymers of different molecular weights were synthesized by a suspension polymerization and precipitation polymerization method. The rheology behaviors of the synthesized PAN copolymers were investigated in relation to their molecular weight, solid content and melting temperature. The influence of "historical effects" on the spinning solution of PAN was studied by analyzing the laws of viscosity considering the diversification time and temperature. The viscosity disciplines of each spinning solution conformed well to the rheological universal laws in a comparison of the suspension polymerization product with that of precipitation polymerization. Viscosity changes in the swelling process of dissolution were gentler in the suspension polymerization product; a small amount of water will quickly debase the solution viscosity, and high-speed mixing can greatly shorten the time required by the spinning solution to reach the final viscosity.

A Deep Investigation of the Thermal Decomposition Process of Supported Silver Catalysts

  • Jiang, Jun;Xu, Tianhao;Li, Yaping;Lei, Xiaodong;Zhang, Hui;Evans, D.G.;Sun, Xiaoming;Duan, Xue
    • Bulletin of the Korean Chemical Society
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    • v.35 no.6
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    • pp.1832-1836
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    • 2014
  • A deep understanding of the metallic silver catalysts formation process on oxide support and the formation mechanism is of great scientific and practical meaning for exploring better catalyst preparing procedures. Herein the thermal decomposition process of supported silver catalyst with silver oxalate as the silver precursor in the presence of ethylenediamine and ethanolamine is carefully investigated by employing a variety of characterization techniques including thermal analysis, in situ diffuse reflectance infrared Fourier transform spectroscopy, scanning electron microscopy, and X-ray diffraction. The formation mechanism of supported silver particles was revealed. Results showed that formation of metallic silver begins at about $100^{\circ}C$ and activation process is essentially complete below $145^{\circ}C$. Formation of silver was accompanied by decomposition of oxalate group and removal of organic amines. Catalytic performance tests using the epoxidation of ethylene as a probe reaction showed that rapid activation (for 5 minutes) at a relatively low temperature ($170^{\circ}C$) afforded materials with optimum catalytic performance, since higher activation temperatures and/or longer activation times resulted in sintering of the silver particles.

Identification and Epigenetic Analysis of a Maternally Imprinted Gene Qpct

  • Guo, Jing;He, Hongjuan;Liu, Qi;Zhang, Fengwei;Lv, Jie;Zeng, Tiebo;Gu, Ning;Wu, Qiong
    • Molecules and Cells
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    • v.38 no.10
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    • pp.859-865
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    • 2015
  • Most imprinted genes are concerned with embryonic development, especially placental development. Here, we identified a placenta-specific imprinted gene Qpct. Our results show that Qpct is widely expressed during early embryonic development and can be detected in the telecephalon, midbrain, and rhombencephalon at E9.5-E11.5. Moreover, Qpct is strikingly expressed in the brain, lung and liver in E15.5. Expression signals for Qpct achieved a peak at E15.5 during placental development and were only detected in the labyrinth layer in E15.5 placenta. ChIP assay results suggest that the modification of histone H3K4me3 can result in maternal activating of Qpct.

A New Model and Equation Derived From Surface Tension and Cohesive Energy Density of Coagulation Bath Solvents for Effective Precipitation Polymerization of Acrylonitrile

  • Zhou, You;Xue, Liwei;Yi, Kai;Zhang, Li;Ryu, Seung Kon;Jin, Ri Guang
    • Carbon letters
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    • v.13 no.3
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    • pp.182-186
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    • 2012
  • A new model and resultant equation for the coagulation of acrylonitrile monomers in precipitation polymerization are suggested in consideration of the surface tension (${\gamma}$) and cohesive energy density ($E_{CED}$). The equation was proven to be quite favorable by considering figure fittings from known surface tensions and cohesive energy densities of certain organic solvents. The relationship between scale value of surface tension (${\gamma}$/M) and cohesive energy density of monomers can be obtained by changing the coagulation bath component for effective precipitation polymerization of acrylonitrile in wet spinning.

Highly Enantioselective Addition of Diethylzinc to Aldehydes Catalyzed by Novel Chiral tert-Amino Alcohols

  • Zhang, Cong-Hai;Yan, Sheng-Jiao;Pan, Sheng-Qiang;Huang, Rong;Lin, Jun
    • Bulletin of the Korean Chemical Society
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    • v.31 no.4
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    • pp.869-873
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    • 2010
  • A series of novel chiral tert-amino alcohols 4a-h derived from enantiomerically pure phenylalanine were synthesized efficiently and used as chiral ligands in the catalytic enantioselective ethylation of aldehydes with diethylzinc (diethylzinc-to-aldehyde addition). The use of 10 mol % of the amino alcohols led to the corresponding sec-alcohols with excellent enantioselectivities (up to 100% ee) and high yields.

Butyric Acid Fermentation of Sodium Hydroxide Pretreated Rice Straw with Undefined Mixed Culture

  • Ai, Binling;Li, Jianzheng;Chi, Xue;Meng, Jia;Liu, Chong;Shi, En
    • Journal of Microbiology and Biotechnology
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    • v.24 no.5
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    • pp.629-638
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    • 2014
  • This study describes an alternative mixed culture fermentation technology to anaerobically convert lignocellulosic biomass into butyric acid, a valuable product with wide application, without supplementary cellulolytic enzymes. Rice straw was soaked in 1% NaOH solution to increase digestibility. Among the tested pretreatment conditions, soaking rice straw at $50^{\circ}C$ for 72 h removed ~66% of the lignin, but retained ~84% of the cellulose and ~71% of the hemicellulose. By using an undefined cellulose-degrading butyrate-producing microbial community as butyric acid producer in batch fermentation, about 6 g/l of butyric acid was produced from the pretreated rice straw, which accounted for ~76% of the total volatile fatty acids. In the repeated-batch operation, the butyric acid production declined batch by batch, which was most possibly caused by the shift of microbial community structure monitored by denaturing gradient gel electrophoresis. In this study, batch operation was observed to be more suitable for butyric acid production.

Enhancing Astaxanthin Accumulation in Haematococcus pluvialis by Coupled Light Intensity and Nitrogen Starvation in Column Photobioreactors

  • Zhang, Wen-wen;Zhou, Xue-fei;Zhang, Ya-lei;Cheng, Peng-fei;Ma, Rui;Cheng, Wen-long;Chu, Hua-qiang
    • Journal of Microbiology and Biotechnology
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    • v.28 no.12
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    • pp.2019-2028
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    • 2018
  • Natural astaxanthin mainly derives from a microalgae producer, Haematococcus pluvialis. The induction of nitrogen starvation and high light intensity is particularly significant for boosting astaxanthin production. However, the different responses to light intensity and nitrogen starvation needed to be analyzed for biomass growth and astaxanthin accumulation. The results showed that the highest level of astaxanthin production was achieved in nitrogen starvation, and was 1.64 times higher than the control group at 11 days. With regard to the optimization of light intensity utilization, it was at $200{\mu}mo/m^2/s$ under nitrogen starvation that the highest astaxanthin productivity per light intensity was achieved. In addition, both high light intensity and a nitrogen source had significant effects on multiple indicators. For example, high light intensity had a greater significant effect than a nitrogen source on biomass dry weight, astaxanthin yield and astaxanthin productivity; in contrast, nitrogen starvation was more beneficial for enhancing astaxanthin content per dry weight biomass. The data indicate that high light intensity synergizes with nitrogen starvation to stimulate the biosynthesis of astaxanthin.