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Molecular mechanism of a coastal cyanobacterium Synechococcus *** 7002 adapting to changing phosphate concentrations

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Marine Life science & Technology 2024年第3期6卷 562-575页

作者： Qiao-Wei Sun Yu Gao Jordan Wang Fei-xue Fu Cheng-Wen Yong Shuang-Qing Li Hai-Long Huang Wei-Zhong Chen Xin-Wei Wang Hai-Bo Jiang School of Marine sciences Ningbo UniversityNingbo 315211China Southern Marine science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China School of Life sciences Central China Normal UniversityWuhan 430079China Department of Biological sciences University of Southern CaliforniaLos AngelesCA 90089USA

Phosphorus concentration on the surface of seawater varies greatly with different environments,especially in *** molecular mechanism by which cyanobacteria adapt to fluctuating phosphorus bioavailability is still *** this study,transcriptomes and gene knockouts were used to investigate the adaptive molecular mechanism of a model coastal cyanobacterium Synechococcus *** 7002 during periods of phosphorus starvation and phosphorus recovery(adding sufficient phosphorus after phosphorus starvation).The findings indicated that phosphorus deficiency affected the photosynthesis,ribosome synthesis,and bacterial motility pathways,which recommenced after phosphorus was *** more,most of the metabolic pathways of cyanobacteria were enhanced after phosphorus recovery compared to the control which was kept in continuous phosphorus replete *** on transcriptome,54 genes potentially related to phosphorusdeficiency adaptation were selected and knocked out individually or in *** was found that five mutants showed weak growth phenotype under phosphorus deficiency,indicating the importance of the genes(A0076,A0549-50,A1094,A1320,A1895)in the adaptation of phosphorus *** mutants were found to grow better than the wild type under phosphorus deficiency,suggesting that the products of these genes(A0079,A0340,A2284–86)might influence the adaptation to phosphorus *** analysis revealed that cyanobacteria exposed to highly fluctuating phosphorus concentrations have more sophisticated phosphorus acquisition *** results elucidated that Synechococcus *** 7002 have variable phosphorus response mechanisms to adapt to fluctuating phosphorus concentration,providing a novel perspective of how cyanobacteria may respond to the complex and dynamic environments.

关键词： Synechococcus sp PCC 7002 Phosphorus fluctuation Cyanobacteria ・Gene knockout Molecular mechanism

Boundedness for multilinear fractional integral operators on Herz type spaces

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Applied Mathematics(A Journal of Chinese Universities) 2008年第4期23卷 437-446页

作者： SHI Yan-long TAO Xiang-xing Dept. of Math. Faculty of Science Ningbo Univ. Ningbo 315211 China

In this paper the boundedness for the multilinear fractional integral operator Iα^（m） on the product of Herz spaces and Herz-Morrey spaces are founded, which improves the Hardy- Littlewood-Sobolev inequality for classical fractional integral Iα. The method given in the note is useful for more general multilinear integral operators.

关键词： multilinear fractional integral Herz space homogeneous Herz-Morrey space product space

Exploring binding mode for styrylquinoline HIV-1 integrase inhibitors using comparative molecular field analysis and docking studies

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Acta Pharmacologica Sinica 2004年第7期25卷 104-112页

作者： Xiao-hui MA, Xiao-yi ZHANG, Jian-jun TAN, Wei-zu CHEN, Cun-xin WANG2 College of Lifescience and Bioengineering, Beijing University of Technology, Beijing 100022, China College of Life science and Bioengineering Beijing University of Technology 北京 100022

AIM: To understand pharmacophore properties of styrylquinoline derivatives and to design inhibitors of HIV-1 integrase. METHODS: Comparative molecular field analysis (CoMFA) was performed to analyze three-dimen- sional quantitative structure-activity relationship (3D-QSAR) of styrylquinoline derivatives. Thirty-eight compounds were randomly divided into a training set of 28 compounds and a test set of 10 compounds. The stability of 3D- QSAR models was proved by the analysis of cross-validated and non-cross-validated methods. Moreover, the binding mode of these compounds and integrase was constructed by AutoDock program. RESULTS: The CoMFA model of the training compounds was reasonably predicted with cross-validated coefficient (q2) and conventional (r2) values (up to 0.696 and 0.754). Then the model was validated by the test set. The resulting CoMFA maps visualized structural requirements for the biological activity of these inhibitors. Docking results showed that a carboxyl group at C-7 and a hydroxyl group at C-8 in the quinoline subunit, bound closely to the divalent metal cofactor (Mg2+) around the integrase catalytic site. Moreover, there is a linear correlation between the binding energy of the inhibitors with integrase and their inhibitory effect. CONCLUSIONS: The present study indicated that the CoMFA model together with docking results could give us helpful hints for drug design as well as interpre- tation of the binding affinity between these inhibitors and integrase.

关键词： HIV integrase inhibitors quinolines comparative molecular field analysis AutoDock

Detecting and Identifying in vivo Metabolites of Brodimoprim via LC/ESI-MS with Data-dependent Scanning

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Chemical Research in Chinese Universities 2008年第4期24卷 430-436页

作者： LIN Yan-ping SI Duan-yun LIU Chang-xiao Department of Pharmaceutical Engineering School of Chemical Engineering and Technology Tianjin University Tianjin 300072 P. R. China Tianjin State Key Laboratory of PharmacoMnetics and Pharmacodynamics Tianjin Institute of Pharmaceutical Research Tianjin 300193 P. R. China

The present article covers a simple approach to detect and subsequently identify in vivo metabolites of brodimoprim, using high performance liquid chromatography coupled to ion trap mass spectrometer（LC/ESI-MS）, which is based on a data-dependent acquisition of isotope ions and result verified by full scan mass spectrum. The distinguished advantage of data-dependent scan is rapidness because it requires minimum sample preparation, and all the necessary data can be obtained in one chromatographic run. In addition, it is highly sensitive and selective, allowing detection of trace metabolites even in the presence of complex biomatrix. As a result, four phase-Ⅰ（M1--M4） and four Phase-Ⅱ（M5--M8） metabolites of brodimoprim were identified in urine after the oral administration of hrodimoprim to Wistar rats. Their chemical structures were proposed based on the interpretation of their CID fragmentation characterizations and the metabolic pathway was exhibited in this article.

关键词： LC/ESI-MS Data-dependant scan Metabolite identification Brodimoprim

Static analysis of ultra-thin beams based on a semi-continuum model

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Acta Mechanica Sinica 2011年第5期27卷 713-719页

作者： Cheng Li Zhi-Jun Zheng Ji-Lin Yu C.W. Lim CAS Key Laboratory of Mechanical Behaviorand Design of Materials University of Science and Technology of China230027 Hefei China Department of Building and Construction City University of Hong KongTat Chee Avenue KowloonHong Kong SAR China

A linear semi-continuum model with discrete atomic layers in the thickness direction was developed to investigate the bending behaviors of ultra-thin beams with nanoscale *** theoretical results show that the deflection of an ultra-thin beam may be enhanced or reduced due to different relaxation *** the relaxation coefficient is greater/less than one,the deflection of micro/nano-scale structures is enhanced/reduced in comparison with macro-scale ***,two opposite types of size-dependent behaviors are observed and they are mainly caused by the relaxation *** with the classical continuum model,exact nonlocal stress model and finite element model （FEM） verify the validity of the present semi-continuum *** particular,an explanation is proposed in the debate whether the bending stiffness of a micro/nano-scale beam should be greater or weaker as compared with the macro-scale *** characteristics of bending stiffness are proved to be associated with the relaxation coefficients.

关键词： Bending stiffness · MEMS/NEMS · Relaxation coefficient · Semi-continuum model · Size-dependence

A Dimension-Splitting Variational Multiscale Element-Free Galerkin Method for Three-Dimensional Singularly Perturbed Convection-Diffusion Problems

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Computer Modeling in Engineering & sciences 2023年第4期135卷 341-356页

作者： Jufeng Wang Yong Wu Ying Xu Fengxin Sun College of Finance&Information Ningbo University of Finance&EconomicsNingbo315175China Faculty of science Ningbo University of TechnologyNingbo315016China

By introducing the dimensional splitting(DS)method into the multiscale interpolating element-free Galerkin(VMIEFG)method,a dimension-splitting multiscale interpolating element-free Galerkin(DS-VMIEFG)method is proposed for three-dimensional(3D)singular perturbed convection-diffusion(SPCD)*** the DSVMIEFG method,the 3D problem is decomposed into a series of 2D problems by the DS method,and the discrete equations on the 2D splitting surface are obtained by the VMIEFG *** improved interpolation-type moving least squares(IIMLS)method is used to construct shape functions in the weak form and to combine 2D discrete equations into a global system of discrete equations for the three-dimensional SPCD *** solved numerical example verifies the effectiveness of the method in this paper for the 3D SPCD *** numerical solution will gradually converge to the analytical solution with the increase in the number of *** extremely small singular diffusion coefficients,the numerical solution will avoid numerical oscillation and has high computational stability.

关键词： Dimension-splitting multiscale interpolating element-free Galerkin(DS-VMIEFG)method interpolating variational multiscale element-free Galerkin(VMIEFG)method dimension splitting method singularly perturbed convection-diffusion problems

Numerical evaluations on the effects of thermal properties on the thermo-mechanical behaviour of a phase change concrete energy pile

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Energy and Built Environment 2023年第1期4卷 1-12页

作者： Weibo Yang Binbin Yang Feng Wang Naidong Jing College of Electrical Energy and Power EngineeringYangzhou UniversityChina Hengtong Construction Group Co.Ltd YangzhouJiangsuChina Jiangsu Tongya Housing Industrialization Technology Co.Ltd YangzhouJiangsuChina

Energy pile is a kind of economic and efficient geothermal utilization technology that the ground heat exchanger(GHE)used in ground source heat pump(GSHP)is embedded into building pile foundation to realize heat ex-change with surrounding *** phase change material(PCM)into the energy pile can not only reduce the temperature variation and thermal deformation range of energy pile,but also improve its energy storage and heat transfer *** this work,phase change concrete energy pile(PCCEP)is proposed by using PCM as a part of backfill material of energy pile.A three-dimensional numerical model is developed to find the influences of thermal properties of PCCEP on its thermo-mechanical *** to the model,the in-fluences of thermal conductivity,phase change latent heat(PCLE)and phase change temperature(PCT)on the thermal performance and mechanical characteristics of PCCEP are numerically *** can be seen that for improving heat transfer performance of PCCEP,the thermal conductivity should be increased,but from the perspective of reducing change of pile displacement,axial force and side friction resistance,the thermal conduc-tivity should be *** heat release mode,lower PCT and larger PCLE contribute to the improvement of thermal performance of PCCEP,and accordingly the rise range of pile temperature,pile displacement change and pile thermal stress can all be *** experimental validation on the model shows that the simulation values of pile wall middle temperature(PWMT)and pile top displacement are agreed well with the corresponding experimental results,the real-time relative error of PWMT and pile top displacement are respectively within 5.1 and 12%.

关键词： GSHP Energy pile Phase change concrete Thermo-mechanical behaviour Numerical evaluation

Cooperative energy transfer in Tm^(3+)and Yb^(3+) co-doped phosphate glasses

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Journal of Rare Earths 2013年第2期31卷 164-168页

作者：徐波杨斌张约品夏海平王金浩 Key Laboratory of Photo-electronic Materials Ningbo University

An efficient near-infrared （NIR） quantum cutting （QC） in Tm3＋ and Yb3＋ co-doped phosphate glasses was demonstrated, which involved the emission of two NIR photons from an absorbed visible photon via a cooperative energy transfer （CET） from Tm3＋ to Yb3＋ ions. Judd-Ofelt （J-O） theory was used to calculate the intensity parameters （ 2 , 4 , 6 ）, the radiative transition rates （Ar ）, and radiative transition lifetime （τ rad ） of Tm3＋ . Based on Inokuti-Hirayama＇s model, the energy transfer processes were studied and results indicated that the energy transfer of the electric dipole-dipole （Edd） was dominant in this system. Quantum efficiency related to Yb 3＋ concentration was calculated, and the maximum QE efficiency reached 169.8%.

关键词： phosphate glass energy transfer quantum cutting I-H model rare earths

Isolation of Chloroplasts from Marine Microalga Isochrysis galbana Parke for Their Lipid Composition Analysis

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Journal of Ocean University of China 2022年第1期21卷 225-235页

作者： ZHONG Ye LI Yanrong XU Jilin CAO Jiayi ZHOU Chengxu YAN Xiaojun Key Laboratory of Applied Marine Biotechnology Ningbo UniversityNingbo 315211China Collaborative Innovation Center for Zhejiang Marine High-Efficiency and Healthy Aquaculture Ningbo UniversityNingbo 315211China Fujian Baozhi Aquatic science and Technology Co. Ltd.Zhangzhou 363503China ningbo Institute of Oceanography Ningbo 315211China

Marine microalga Isochrysis galbana is an important feed species with a high nutritional *** from other uni-cellular algae,its cell contains two chloroplasts which are the major sites for lipid ***,we optimized a chloroplast isola-tion approach suitable for the isolation of *** chloroplasts and determined the purity and integrity of the isolated chloroplasts through microscopic observations and enzyme activity *** chloroplast lipids were analyzed with a ultrahigh-performance li-quid chromatography-Q Exactive Orbitrap-mass *** newly developed isolation approach is simple and reliable to isolate chloroplasts with high integrity and *** average yield of intact chloroplasts was 15.3%±0.1%.Glycolipids and acyl-glycerols were the main chloroplast *** accounted for 56.6%of chloroplast ***(DGDG),monogalactosyldiacylglycerol(MGDG)and sulfoquinovosyldiacylglycerol(SQDG)were the main *** fatty acyl R1/R2 were mostly 18:4/16:1,18:3/16:1 and 18:4/18:5 in DGDGs,14:0/18:4,18:4/18:5,18:4/18:4 and 18:3/18:4 in MGDGs and 16:0/14:0,16:0/18:3,and 18:4/18:3 in *** addition,diacylglycerol(DAG)was the most abundant acylglycerols;the content of 22:6/18:4-DAG was the *** was a little amount of glycosphingolipid(GSL)in ***(DGMG),monogalactosylmonoglyceride(MGMG),sulfoquinovosylmonoacylglycerol(SQMG),monoglyceride(MAG),phospholi-pids(PLs),ceramide(Cer)and betaine lipids were nearly undetectable in *** fatty acid proportions of DGDGs,MGDGs,SQDGs,DAGs,triglycerides(TAGs)and GSLs were either higher or lower than or similar to those of ***,our isolation approach is applicable to many aspects of chloroplast biology,and may offer a reference for the isolation of chloroplasts from other marine microalgae.

关键词： Isochrysis galbana chloroplast isolation method lipid analysis chloroplast lipid