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Rim-differentiation vs. mixture of constitutional isomers: A binding study between pillar[5]arene-based glycoclusters and lectins from pathogenic bacteria

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chinese chemical Letters 2023年第2期34卷 214-218页

作者： Zhiping Liu Fanny Demontrond Anne Imberty Andrew c.-H.Sue Sébastien Vidal Hongxia Zhao Tianjin Key Lab for Modern Drug Delivery and High-Efficiency School of Pharmaceutical Science and TechnologyTianjin UniversityTianjin 300072China Institut de chimie et Biochimie Moléculaires et Supramoléculaires Laboratoire de Chimie Organique 2-GlycochimieUMR 5246CNRSUniversitéClaude Bernard Lyon 1Universitéde LyonVilleurbanne 69622France cNRS Univ.Grenoble AlpesCERMAVGrenoble 38000France college of chemistry and chemical Engineering Xiamen UniversityXiamen 361005China cNRS Institut de Chimie des Substances NaturellesUniversitéParis-SaclayUPR 2301Gif-sur-Yvette 91198France

Macrocycle-based glycoclusters, on account of their promising anti-adhesive properties against bacteria,are potential therapeutic alternatives to classic antibiotics through the much less explored anti-adhesive strategy. In this study, a series of constitutionally-pure pentavalent glycoclusters was prepared by conjugating assorted azido-carbohydrates onto a penta-propargyl rim-differentiated pillar[5]arene(RD-P[5])scaffold through cu(I)-catalyzed azide–alkyne cycloaddition “click” reactions. Their binding towards therapeutically relevant bacterial lectins, such as Lec A and Lec B from Pseudomonas aeruginosa and concanavalin A(con A), were evaluated subsequently by isothermal titration calorimetric studies. Most of these isomerfree RD-P[5] pentavalent glycoclusters, except the fucosylated ones, display good affinities to ***, the dissociation constants observed are similar to those displayed by an analogous pentavalent glycocluster consisting of four P[5] constitutional isomers, in which the RD-P[5] component merely accounts for 7% in the mixture. Our results revealed that high constitutional purity is not essential for achieving effective multivalent interactions between P[5]-based glycoclusters and lectins, presumably as a result of the conformationally labile nature of the P[5] scaffold. This information provides valuable design principles for low-cost and facile syntheses of glycosylated P[5]s for biomedical applications.

关键词： Glycocluster Lectin Pillararene Multivalency constitutional purity

Nordhaus-Gaddum Results for the Sum of the Induced Path Number of a Graph and Its complement

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Acta Mathematica Sinica,English Series 2012年第12期28卷 2365-2372页

作者： Johannes H.HATTINGH Ossama A.SALEH Lucas c.VAN DER MERWE Terry J.WALTERS Department of Mathematics East Carolina University Department of Mathematics University of Johannesburg Department of Mathematics University of Tennessee at Chattanooga

The induced path number p（G） of a graph G is defined as the minimum number of subsets into which the vertex set of G can be partitioned so that each subset induces a path. Broere et hi. proved that if G is a graph of order n, then 〈 p（G）＋ p（G）〈3n/2] . In this paper,_we characterize [3n/2], improve the lower bound on p（G）＋ p（G） by one when the graphs G for which p（G） -4- p（G） = 3n n is the square of an odd integer, and determine a best possible upper bound for p（G）＋ p（G） when neither G nor G has isolated vertices.

关键词： Nordhaus-Gaddum induced path number

cREVIcE cORROSION BEHAVIOR OF X70 STEEL IN HcO_3^- SOLUTION UNDER cATHODIc POLARIZATION

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Acta Metallurgica Sinica(English Letters) 2008年第4期21卷 235-244页

作者： c.W. Du X.G. Li X. chen P. Liang H. Guo School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Liaoning University of Petroleum and chemical Technology ~shun 113001 China

The crevice corrosion behavior of XTO steel was investigated with a wedge-shaped crevice assembly under -1000 m V （ScE） cathodic polarization in the solutions with various HcO3 concentrations. The potential, current, pH and the oxygen content within the crevice were measured with or without outside coupled specimen. The results indicated that the polarization potential of XTO steel in the crevice dropped with the increase of time under the cathodic polarization. There was a remarkable influence of HcO3 concentration on the potential of XTO steel in the crevice. When HcO3 concentration was up to 0.125%, the surface of the metal was covered with the corrosion products that resulted in the polarization extent of XTO steel decreased. The pH value in the crevice rose and it dropped gradually from the crevice mouth to the bottom under the cathodic polarization. With the increasing of HcO3 concentration, the hydrolyzation reaction of metal in the crevice bottom aggravated. Most of the dissolved oxygen in the crevice was consumed by the cathodic current. The maximum cathodic current on the metal surface was at the crevice mouth and it was much more than that at the crevice bottom.

关键词： cathodic polarization XTO steel Potential pH value Oxygen

Nose-to-brain delivery of macromolecules mediated by cell-penetrating peptides

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Acta Pharmaceutica Sinica B 2016年第4期6卷 352-358页

作者： Tingting Lin Ergang Liu Huining He Meong cheol Shin cheol Moon Victor c.Yang Yongzhuo Huang Tianjin Key Laboratory on Technologies Enabling Development of clinical Therapeutics and Diagnosis School of Pharmacy Tianjin Medical University Shanghai Institute of Materia Medica Chinese Academy of Sciences college of Pharmacy The University of Michigan college of Pharmacy and Research Institute of Pharmaceutical Sciences Gyeongsang National University college of Pharmacy Sunchon National University

Brain delivery of macromolecular therapeutics (e.g., proteins) remains an unsolved problem because of the formidable blood brain bather (BBB). Although a direct pathway of nose-to-brain transfer provides an answer to circumventing the BBB and has already been intensively investigated for brain delivery of small drugs, new challenges arise for intranasal delivery of proteins because of their larger size and hydrophilicity. h order to overcome the bathers and take advantage of available pathways (e.g., epithelial tight junctions, uptake by olfactory neurons, transport into brain tissues, and intra-brain diffusion), a low molecular weight protamine (LMWP) cell-penetrating peptide was utilized to facilitate nose-to-brain transport. cell-penetrating peptides (cPP) have been widely used to mediate macromolecular delivery through many kinds of biobarriers. Our results show that conjugates of LMWP proteinsare able to effectively penetrate into the brain after intranasal administration. The cPP-based intranasal method highlights a promising solution for protein therapy of brain diseases. (c) 2016 chinese Pharmaceutical Association and Institute of Materia Medica, chinese Academy of Medical Sciences. Production and hosting by Elsevier B.V.

关键词： Intranasal protein delivery Brain targeting cell-penetrating peptide Low molecular weigh protamine Blood brain barrier

Influence of temperature cycling and pore fluid on tensile strength of chalk

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第2期11卷 277-288页

作者： T.Voake A.Nermoen c.Ravn?s R.I.Korsnes I.L.Fabricius University of Stavanger The National IOR center of Norway University of Stavanger NORcE Norwegian Research centre AS Technical University of Denmark

calcite has a highly anisotropic thermal expansion coefficient, and repeated heating and cooling cycles can potentially destabilize chalks by breaking cement bonds between neighboring particles. Based on tensile strength measurements, we investigated how temperature cycles induce weakening of *** strength tests were performed on chalk specimens sampled from Kansas(USA) and Mons(Belgium), each with differing amounts of contact cement. Samples of the two chalk types were tested in dry and water-saturated states, and then exposed to 0, 15, and 30 temperature cycles in order to find out under what circumstances thermally induced tensile strength reduction occurs. The testing results show that the dry samples were not influenced by temperature cycling in either of the chalk types. However, in the water-saturated state, tensile strength is increasingly reduced with progressive numbers of temperature cycles for both chalk samples, especially for the more cemented Kansas chalk. The Kansas chalk demonstrated higher initial tensile strength compared to the less cemented Mons chalk, but the strength of both chalks was reduced by the same relative proportion when undergoing thermal cycles in the water-saturated state.

关键词： Tensile strength Weakening by heating and cooling cycles Anisotropic thermal expansion

A Sharding Scheme Based on Graph Partitioning Algorithm for Public Blockchain

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computer Modeling in Engineering & Sciences 2024年第6期139卷 3311-3327页

作者： Shujiang Xu Ziye Wang Lianhai Wang Miodrag J.Mihaljevi′c Shuhui Zhang Wei Shao Qizheng Wang Key Laboratory of computing Power Network and Information Security Ministry of EducationShandong Computer Science CenterQilu University of Technology(Shandong Academy of Sciences)Jinan250014China Shandong Provincial Key Laboratory of computer Networks Shandong Fundamental Research Center for Computer ScienceJinan250014China Mathematical Institute The Serbian Academy of Sciences and ArtsBelgrade11000Serbia

Blockchain technology,with its attributes of decentralization,immutability,and traceability,has emerged as a powerful catalyst for enhancing traditional industries in terms of optimizing business ***,transaction performance and scalability has become the main challenges hindering the widespread adoption of *** to its inability to meet the demands of high-frequency trading,blockchain cannot be adopted in many *** improve the transaction capacity,researchers have proposed some on-chain scaling technologies,including lightning networks,directed acyclic graph technology,state channels,and shardingmechanisms,inwhich sharding emerges as a potential scaling ***,excessive cross-shard transactions and uneven shard workloads prevent the sharding mechanism from achieving the expected *** paper proposes a graphbased sharding scheme for public blockchain to efficiently balance the transaction *** crossshard transactions and evening-out workloads among shards,the scheme reduces transaction confirmation latency and enhances the transaction capacity of the ***,the scheme can achieve a high-frequency transaction as well as a better blockchain *** results show that the scheme effectively reduces the cross-shard transaction ratio to a range of 35%-56%and significantly decreases the transaction confirmation latency to 6 s in a blockchain with no more than 25 shards.

关键词： Blockchain sharding graph partitioning algorithm

Zooplankton Distribution in coastal Water off Gopalpur,North-Western Bay of Bengal

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Journal of Ocean University of china 2018年第4期17卷 879-889页

作者： S.K.BALIARSINGH Suchismita SRIcHANDAN Aneesh A.LOTLIKER T.Srinivasa KUMAR K.c.SAHU Indian National center for Ocean Information Services Hyderabad 500090 India Department of Marine Sciences Berhampur UniversityOdisha 760007India

An interannual study on zooplankton abundance, biomass, and species composition was carried out during different seasons in two local coastal water types off Gopalpur, north-western Bay of Bengal. Although, Type-1 was observed with higher zooplankton abundance in comparison to Type-2, pattern of variation followed similar seasonal trends in both water types during individual years. Well pronounced seasonality was observed in zooplankton distribution. Zooplankton community was composed of 217 holoplankton and 22 meroplankton. The holoplankton community was predominated by copepod in terms of species diversity and abundance followed by hydrozoa, tintinnida, malacostraca, gastropoda, chaetognatha and chordata. The meroplankton were represented by larval forms viz. bivalve veliger, brachyuran zoea larvae, caridean larvae, copepod nauplii, fish egg and gastropod veliger. Dominance of copepod species viz. Acrocalanus longicornis, Paracalanus aculeatus and Paracalanus parvus were observed frequently in both water types. The species richness was higher in Type-1 in comparison to Type-2 during both the years. Salinity regimes and availability of phytoplankton prey influenced the distribution and species composition of zooplankton assemblage.

关键词： copepod zooplankton phytoplankton salinity monsoon Bay of Bengal

MATHEMATIcAL MODEL FOR THE ENTERPRISE cOMPETITIVE ABILITY AND PERFORMANcE THROUGH A PARTIcULAR EMDEN-FOWLER EQUATION u〞-n^(-q-1)u(n)~q=0

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Acta Mathematica Scientia 2018年第4期38卷 1311-1321页

作者： Yue-Loong cHANc Meng-Rong LI c. Jack YUE Yong-Shiuan LEE Tsung-Jui cHIANG-LIN Department of Phycology National Chengchi University Taipei China Department of Mathematical Sciences National Chengchi University Taipei China Department of Statisitics National Chengchi University Taipei China Graduate Institute of Finance National Taiwan University of Science and Technology Taipei China

In this article, we work with the ordinary equation u″-n-q-1u（n）q=0 and learn some interesting phenomena concerning the blow-up and the blow-up rate of solution to the equation.

关键词： estimate life-span blow-up blow-up rate competitive ability performance

Identification of binding interactions between myeloperoxidase and its antibody using SERS

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Nano-Micro Letters 2010年第2期2卷 74-82页

作者： E.S.Papazoglou S.Babu S.Mohapatra D.R.Hansberry c.Patel School of Biomedical Engineering Science & Health Systems Drexel University

Surface Enhanced Raman Spectroscopy(SERS) is a widely used spectroscopic method that can dramatically increase the sensitivity of Raman spectroscopy and has demonstrated significant benefit in the identification of biological molecules. We report the use of SERS in differentiating the bound immunocomplex of myeloperoxidase(MPO) and its antibody from the unbound complex and its individual components. The SERS signal was enabled by gold nanoparticles attached to MPO, p Ab and their immunocomplex at an excitation wavelength of 785 nm. The obtained SERS spectrum of MPO is in agreement with previous literature. comparative SERS spectrum analysis of MPO, p Ab, and their immunocomplex reveals the significant peak shifts and intensity variations caused by the conformational changes due to the immunocomplex formation. Several key areas have been identified which correspond to specific amino acids being shielded from undergoing resonance while new amino acid residues are made visible in the SERS spectrum of the immunocomplex and could be a result of conformational binding. Our work demonstrates the capability of SERS to identify binding events and differentiate an immunocomplex from its unbound components with direct applications in biosensors.

关键词： Gold nanoparticle Antigen Immunocomplex Biosensors