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Antibacterial and cytotoxic metabolites produced by Streptomyces tanashiensis BYF-112 isolated from Odontotermes formosanus

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Chinese j.urnal of Natural Medicines 2024年第9期22卷 822-830页

作者： wu j. SONG T. ZHANG L. HUANG Z. HUANG F. YIN C. ZHANG S. LIU X. ZHANG Y. School of Life Science Anhui Agricultural University Hefei 230036 China School of Pharmacy Anhui Medical University Hefei 230036 China

Chemical investigations of the termite-associated Streptomyces tanashiensis BYF-112 resulted in the discovery of four novel alkaloid derivatives: vegfrecines A and B (1 and 2), exfoliazone A (3), and venezueline H (7), in addition to nine known metabolites (4−6, 8−13). The structures of these compounds were elucidated through comprehensive spectroscopic analysis and comparison with existing literature data. Antibacterial assays revealed that viridomycin A (11) exhibited potent antibacterial activity against Staphylococcus aureus, with a zone of inhibition (ZOI) of 12.67 mm, in comparison to a ZOI of 17.67 mm for the positive control gentamicin sulfate. Viridomycin A (11) showed moderate activity against Micrococcus tetragenus and Pseudomonas syringae pv. actinidae, with ZOI values of 15.50 and 14.33 mm, respectively, which were inferior to those of gentamicin sulfate (34.67 and 24.00 mm). Viridomycin F (12) also exhibited moderate antibacterial effects against S. aureus, M. tetragenus, and P. syringae pv. actinidae, with ZOI values of 8.33, 16.50, and 10.83 mm, respectively. Cytotoxicity assays demonstrated that viridobruunine A (5), exfoliazone (6), viridomycin A (11), and X-14881E (13) exhibited significant cytotoxicity against human malignant melanoma (A375), ovarian cancer (SKOV-3), and gastric cancer (MGC-803) cell lines, with IC50 values ranging from 4.61 to 19.28 μmol·L−1. Furthermore, bioinformatic analysis of the complete genome of S. tanashiensis suggested a putative biosynthetic gene cluster (BGC) responsible for the production of compounds 1−12. These findings indicate that the secondary metabolites of insect-associated S. tanashiensis BYF-112 hold promise as potential sources of novel antibacterial and anticancer agents. © 2024 China Pharmaceutical University

关键词： Alkaloid Antibacterial activity Biosynthetic pathway Cytotoxic activity Odontotermes formosanus Streptomyces tanashiensis

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A Novel Training Algorithm of Genetic Neural Networks and Its Application to Classification

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j.urnal of Systems Engineering and Electronics 2001年第3期12卷 76-84页

作者： Xiao, j. wu, j. Yang, S. School of Mechanics Huazhong Univ. of Sci. and Technol. Wuhan 430074 China

First of all, this paper discusses the drawbacks of multilayer perceptron (MLP), which is trained by the traditional back propagation (BP) algorithm and used in a special classification problem. A new training algorithm for neural networks based on genetic algorithm and BP algorithm is developed. The difference between the new training algorithm and BP algorithm in the ability of nonlinear approaching is expressed through an example, and the application foreground is illustrated by an example.

关键词： Backpropagation Computer simulation Genetic algorithms Mathematical models Nonlinear control systems Problem solving

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Development and application of functional gene arrays for microbial community analysis

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中国有色金属学会会刊：英文版 2008年第6期18卷 1319-1327页

作者： Z. L. HE j. D. VAN NOSTRAND L.Y. wu j. Z. ZHOU Institute for Environmental Genomics Department of Botany and Microbiology University of Oklahoma Norman OK 73019 USA

功能的基因标记能关于功能的基因差异和微生物引起的社区的潜在的活动提供重要信息。尽管 microarray 技术成功地被使用了为纯文化学习基因表示，简单、人工的微生物引起的社区，改编如此的一种技术分析复杂微生物引起的社区仍然以设计... 详细信息

功能的基因标记能关于功能的基因差异和微生物引起的社区的潜在的活动提供重要信息。尽管 microarray 技术成功地被使用了为纯文化学习基因表示，简单、人工的微生物引起的社区，改编如此的一种技术分析复杂微生物引起的社区仍然以设计，样品准备，和数据分析提出很多挑战。这个工作集中于功能的基因数组(FGA ) 的开发和应用程序为微生物引起的社区研究指向关键功能的基因标记。一些与 FGA 有关明确地给问题调音，例如 oligonucleotide 探查设计， nucleic 酸抽取和纯化，数据分析，特性，敏感，和量的能力详细被讨论。最近的研究证明了 FGA 能从许多自然环境关于微生物引起的社区提供特定、敏感、潜在地量的信息并且控制生态系统。这种技术被期望革命化微生物引起的社区的分析，并且连接微生物引起的结构到生态系统工作。

关键词：微数列应用函数基因标记微生物种群

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A NEURAL NETWORK FOR WELD PENETRATION CONTROL IN GAS TUNGSTEN ARC WELDING

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Acta Metallurgica Sinica(English Letters) 2006年第1期19卷 27-33页

作者： C.S. wu j. Q. Gao Y.H. Zhao Institute of Materials j.ining Shandong University Jinan 250061 China

Realizing of weld penetration control in gas tungsten arc welding requires establishment of a model describing the relationship between the front-side geometrical parameters of weld pool and the back-side weld width with sufficient accuracy. A neural network model is developed to attain this aim. Welding experiments are conducted to obtain the training data set （including 973 groups of geometrical parameters of the weld pool and back-side weld width） and the verifying data set （108 groups）. Two data sets are used for training and verifying the neural network, respectively. The testing results show that the model has sufficient accuracy and can meet the requirements of weld penetration control.

关键词： neural network weld penetration control back-side weld width,gas tungsten arc welding

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MICROSTRUCTURE AND MECHANICAL PROPERTY DEVELOPMENT IN THE SIMULATED HEAT AFFECTED ZONE OF V TREATED HSLA STEELS

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Acta Metallurgica Sinica(English Letters) 2006年第1期19卷 57-67页

作者： Y. T. Chen A.M. Guo L.X. wu j. Zeng P.H. Li National Enterprise Technology Center Wuhan Iron and Steel （Group） Co.Wuhan 430080 China

The simulated heat affected zone （HAZ） of the high strength low alloy （HSLA） steels containing 0%, 0.047%, 0.097% and 0.151% vanadium, respectively, were studied with Gleeble-2000 thermomechanical simulator to determine the influence of vanadium addition on the mechanical properties of the HAZ. The HAZ simulation involved reheating the samples to 1350℃, and then cooling to ambient temperature at a cooling rate of 5℃/s ranging from 800 to 500℃ （△8/5=60s）. The mechanical properties including tensile strength and -20℃ impact toughness were conducted. The microstructures of the base steel and the simulated HAZs were investigated using optical microscope, scanning electron microscope （ SEM ） and transmission electron microscope （TEM）. Based on the systemutic examination, the present work confirmed that about 0.05% vanadium addition to low carbon low alloy steels resulted in expected balance of strength and toughness of the HAZ. And more than 0.10% levels addition led to detrimental toughness of the HAZ SEM study showed that the simulated 0.097% and 0.151%V HAZs consisted of more coarse ferrite plates with greater and more M-A constituents along austenite grain and ferrite plate bound- aries. The impact fracture surfaces of the simulated 0.097% and 0.151%V HAZs showed typically brittle mode with predominant cleavages. The size of the facet in the fracture surface increased with increasing vanadium level from 0.097% to 0.151%.As a result, the simulated 0.151% V HAZ has the lowest impact toughness of the four specimens.

关键词： vanadium high strength low alloy (HSLA) steel mechanical property,heat affected zone (HAZ)

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Approximate Failures Semantics for Polynomial Labelled Transition Systems

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j.urnal of Donghua University(English Edition) 2013年第6期30卷 472-476页

作者： Wang C. Liang Y. wu j.-Z. Tan H.-Y. School of Computer and Information Technology Beijing Jiaotong University Beijing 100044 China Guangxi Key Laboratory of Hybrid Computation and IC Design Analysis Guangxi University for Nationalities Nanning 530006 China Institute of Actuaries Chinese Academy of Sciences Beijing 100190 China

Labelled transition systems(LTSs) are widely used to formally describe system *** labels of LTS are extended to offer a more satisfactory description of behaviour by refining the abstract labels into multivariate *** labels can be simplified by numerous numerical approximation *** LTSs that can not apply failures semantics equivalence in description and verification may have a chance after using approximation on *** technique that combines approximation and failures semantics equivalence effectively alleviates the computational complexity and minimizes LTS.

关键词： labelled transition system (LTS) failures semantics numerical approximation

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Correlation research between the patients with cerebral infarction in different ages and blood lipid levels

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中国临床康复 2003年第1期7卷 130-131页

作者： j.ang B. Guo C. Tan L. wu j. Xiao Z. Liao j. Department of Neurology Second Xiangya Hospital Central South University Changsha 410011 Hunan Province China Department of Neurology Third People's Hospital of Changde Changde 415000 Hunan Province China

AIM：To investigate the relationship between the patients with cerebral infarction(CI)in different ages and blood lipid ***:The serum concentration of blood lipid levels were measured in 211 patients with CI and 144 control ***:The level of lipoprotein(a)[Lp(a)] in the young adults with CI and the levels of triglyceride(TG),total cholesterol(TC),low-density lipoprotein-cholesterol(LDL-C),apolipoproteinB100(ApoB100) and Lp(a) in the subgroup of mid-adults with CI were much higher than corresponding *** levels of TC,LDL-C ApoB100 and Lp(a) in the subgroup of olds were significantly higher when compared with the corresponding controls,while the high-density lipoprotein-cholesterol(HDL-C) level was *** linear regression showed that age had positive correlation to TC and ApoB100 and negative correlation to ***:There are different disturbances of blood lipid metabolism in the patients with CI in different *** serum Lp(a) levels may be an independent risk factor for CI.

关键词：脑梗死血脂水平相关性研究年龄

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Screening Germplasm Resources of Tea Plant with Less Bitterness and Astringency Index

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j.urnal of Agricultural Science and Technology(B) 2011年第6期1卷 874-880页

作者： L. Y. wu j. K. Lin Department of Tea Sciences Fujian Agriculture and Forestry University Fuzhou 350002 China

The aim of this study was to identify tea varieties with less bitterness and astringency index that could be used as important sources for breeding and in the production of high quality tea. We studied 36 cultivars or lines which had been preserved in Tea Germplasm Garden of Fuj.an. The contents of catechins in spring tea shoots, summer tea shoots and autumn tea shoots in 36 varieties and lines were analyzed by HPLC. Analysis of these tea varieties and lines revealed that the catechins contained in the tea shoots in different seasons are highly variable. The content of ester-catechins in spring and summer tea shoots was higher than that of autumn, while non-ester-catechins did not showed the same characteristic. The content of EGCG showed an extremely significant positive correlation with T1 （T1 = EGC ＋ EGCG ＋ GCG ＋ EGC）, an extremely significant negative correlation with DL-C, the content of EGC showed the same characteristic. Among them, 10 cultivars with less bitterness and astringency index （the annual average bitterness and astringency index 〈 8.0） were considered good candidates as important breeding materials tbr tea infusion quality improvement.

关键词： Camellia sinensis ester-catechins bitterness astringency germplasm resources screening.

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Structural Characterization of Chiral Sulfido Cluster(η~5-C_5H_5) WFeCo(CO)_8 (μ_3-S)

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Chinese j.urnal of Structural Chemistry 1997年第1期16卷 59-63页

作者： Xu F. Sun W.-H. Yang S.-Y. Yin Y.-Q. wu Q.-j. State Key Lab. OXO Synthesis/S. O. Lanzhou Inst. of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China Fuj.an Inst. Res. Struct. of Matter Chinese Academy of Sciences Fuzhou 350002 China

The chiral sulfido cluster (η5-C5H5)WFeCo(CO)8(μ3--S) was synthesized by refluxing a solution of HFe2Co(CO)9 (μ3,--S) and (η5-C5H5)Fe(CO)3Cl in tetrahydrofuran. It was characterized by elemental analysis, IR and 1H/13C--NMR. Theproposal concerning mechanism was discussed herewith and the structure was reportedas well. Crystallographic data: Mr= 563. 85, monoclinicl P21/n(# 14); a= 8. 009(2), b= 17. 600(5), c=12. 003(4) A; β=95. 91(2)°; V= 1683. 0 (9) A3; Z=4;Dc=2. 22 g. cm-3; F(000) = 1048, μ=89. 27 cm-1 ; final R=0. 039 and Rw=0. 049for 2121 observable reflections with (I≥3. cσ(I) ). The crystal structure determinationshows that S atom coordinates to all three metal (W,Fe,Co) atoms in a μ3,-fashion,thetitle cluster core has the tetrahedral skeleton.

关键词： heterometallic cluster carbonyl sulfido tetrahedral framework

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Convexification of Hybrid AC-DC Optimal Power Flow with Line-Commutated Converters

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CSEE j.urnal of Power and Energy Systems 2024年第2期10卷 617-628页

作者： Hongyuan Liang Zhigang Li j.H.Zheng Q.H.wu School of Electric Power Engineering South China University of TechnologyGuangzhou 510641China

Line-commutated converter (LCC)-based high-voltage DC (HVDC) systems have been integrated with bulk AC power grids for interregional transmission of renewable power. The nonlinear LCC model brings additional nonconvexity to optimal power flow (OPF) of hybrid AC-DC power grids. A convexification method for the LCC station model could address such nonconvexity but has rarely been discussed. We devise an equivalent reformulation for classical LCC station models that facilitates second-order cone convex relaxation for the OPF of LCC-based AC-DC power grids. We also propose sufficient conditions for exactness of convex relaxation with its proof. Equivalence of the proposed LCC station models and properties, exactness, and effectiveness of convex relaxation are verified using four numerical simulations. Simulation results demonstrate a globally optimal solution of the original OPF can be efficiently obtained from relaxed model.

关键词： AC-DC power system convex relaxation linecommutated converter optimal power flow second-order cone programming

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