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Poly(1-vinylimidazole) Prospects in Gene Delivery

Chinese Journal of Polymer Science 2019年第7期37卷 637-645页

作者： Elena N.Danilovtseva Stanislav N.Zelinskiy Viktor A.Pal'shin Gayathri Kandasamy uma maheswari Krishnan Vadim V.Annenkov Limnological Institute of the Siberian Branch of the Russian Academy of Sciences 3Ulan-Batorskaya St.P.O. Box 278Irkutsk 664033Russia Centre for Nanotechnology &Advanced Biomaterials (CeNTAB) School of Chemical and BiotechnologySASTRA UniversityThanjavur 613401 Tamil NaduIndia

Polymeric amines are being studied intensively as components of systems for gene delivery in genetic engineering and gene therapy of genetic disorders, including cancer. Despite remarkable achievements in the field, polymeric amines, such as polyethyleneimine, show some disadvantages. Strong interaction between the amine-containing polymer and nucleic acid hampers the release of nucleic acid in the cell cytoplasm. Amine groups can interact with the cell membrane which results in cell death. These limitations of polymeric amines stimulated an investigation of new structures for gene delivery. Imidazole-containing polymers have attracted attention as lesser basic substances, while they are able to interact with polymeric acids. Further development of imidazole-based gene delivery agents requires knowledge about some fundamental aspects of interaction between nucleic acids, and polymeric imidazoles. In this work, we studied the complexation of poly(1-vinylimidazole) and oligomeric DNA. We found that the number of active sites capable of binding with negatively charged phosphate groups is comparable with the number of protonated imidazole units in the case of high molecular weight polymer. The increase in polymer charge by 1-bromopropane quaternizating 1%?5% imidazole units or by decreasing the pH to 6.5?7 considerably increased the ability of poly(1-vinylimidazole) to interact with oligonucleotides. The pH sensitivity of this interaction is interesting for cancer gene therapy because the tumours have a lowered intercellular pH (stable oligonucleotide complex) and a higher extracellular pH which can lead to complex dissociation. Minimal critical length for complexation of quaternized poly(1-vinylimidazole) and DNA is below eight units which corresponds to polymers with amine groups. Fluorescence-tagged poly(1-vinylimidazole) samples were obtained and their potential for monitoring the polymer and polymer-oligonucleotide complex internalization into living cells was demo

关键词： Polymeric amines Oligonucleotides Fluorescence Poly(1-vinylimidazole) Gene delivery

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Bioinspired Water-soluble Polymers with Grafted Polyamine Chains： Synthesis and Complexation with Oligonucleotides

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Chinese Journal of Polymer Science 2018年第10期36卷 1114-1122页

作者： Vadim V.Annenkov uma maheswari Krishnan Viktor A.Pal'shin Stanislav N.Zelinskiy Gayathri Kandasamy Elena N.Danilovtseva Limnological Institute of the Siberian Branch of the Russian Academy of Sciences 3 Ulan-Batorskaya St. P.O. Box 278 Irkutsk 664033 Russia Centre for Nanotechnology & Advanced Biomaterials (CeNTAB) School of Chemical and Biotechnology SASTRA University Thanjavur - 613401 Tamil Nadu India

The siliceous frustules of diatom algae contain complex proteins known as silaffins, which consist of a peptide chain with grafted polyamine chains. These polyamines contain twenty or more nitrogen atoms with trimethylene groups between the nitrogens. We synthesized a set of polymers containing grafted long-chain polyamine fragments by using acryloyl chloride （ACh） polymers and activated acrylic acid copolymers as the starting materials. The new polymers contained 0.05 mol%-3.2 mol% of polyamine chains, which corresponded to 0.06-3.56 mmol·g- 1 amine groups. The new amine-containing polymers formed complexes with short （19-21-mer） deoxyribonucleic acid （DNA） and ribonucleic acid （RNA） strands, and these complexes penetrated into model yeast cells and A549 lung cancer cell. This study demonstrates the potential of these species based on long-chain polyamines to serve as novel gene delivery systems.

关键词： Polyamine Polymeric amine Gene delivery Acryloyl chloride

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Performance Enhancement in Dye-Sensitized Solar Cells with Composite Mixtures of TiO_2 Nanoparticles and TiO_2 Nanotubes

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Acta Metallurgica Sinica(English Letters) 2015年第3期28卷 354-361页

作者： D.maheswari P.Venkatachalam Department of Physics Bharathiar University Department of Physics(DDE) Annamalai University

In the present investigation,a new composite nanostructured photoanodes were prepared using TiO_2 nanotubes（TNTs） with TiO_2 nanoparticles（TNPs）.TNPs were synthesized by sol-gel method,and TNTs were prepared through alkali hydrothermal ***-sensitized solar cells（DSSCs） were fabricated with different photoanodes comprising of various ratios of TNTs ＋ TNPs,synthetic indigo dye as photosensitizer,PMII（l-propyl-3-methylimidazolium iodide） as ionic liquid electrolyte and cobalt sulfide as counter *** structures and morphologies of TNPs and TNTs were analyzed through X-ray diffractometer,transmission electron microscope and scanning electron *** results of the investigation showed that the DSSC-4 made with composite photoanode structure（TNTs/TNPs）（90% of TNPs ＋ 10% of TNTs） had improved photocurrent efficiency（2.11%） than pure TNPs（1.00%） and TNT film（0.78%）.Electrochemical impedance spectra revealed that the composite TNTs/TNPs film-based DSSCs possessed the lowest charge-transfer resistances and longest electron ***,it could be concluded that the composite TNTs/TNPs photoanode facilitates the charge transport rate and enhances the efficiencies of DSSCs.

关键词： TNPs/TNTs composite mixtures Charge recombination Electron transport Photovoltaic parameters EIS analysis

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NDC-IVM:An automatic segmentation of optic disc and cup region from medical images for glaucoma detection

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Journal of Innovative Optical Health Sciences 2017年第3期10卷 118-132页

作者： umarani balakrishnan Department of ECE Trichy Engineering College Sivagnanam NagarKonalaiTrichyTamil Nadu 621132India

Glaucoma is an eye disease that usually occurs with the increased Intra-Ocular Pressure(IOP),which damages the vision of ***,detecting and classifying Glaucoma is an important and demanding task in recent *** this purpose,some of the clustering and segmentation techniques are proposed in the existing ***,it has some drawbacks that include ineficient,inaccurate and estimates only the affected *** order to solve these issues,a Neighboring Differential Clustering(NDC)-Intensity V ariation Making(IVM)are proposed in this *** main intention of this work is to extract and diagnose the abnormal retinal image by identifying the optic *** work includes three stages such as,preprocessing,clustering and *** first,the given retinal image is preprocessed by using the Gaussian Mask Updated(GMU)model for eliminating the noise and improving the quality of the ***,the cluster is formed by extracting the threshold and patterns with the help of NDC *** the segmentation stage,the weight is calculated for pixel matching and ROI extraction by using the proposed IVM ***,the novelty is presented in the clustering and segmentation processes by developing NDC and IVM algorithms for accurate Glaucoma *** experiments,the results of both existing and proposed techniques are evaluated in terms of sensitivity,specificity,accuracy,Hausdorff distance,Jaccard and dice metrics.

关键词： Glaucoma detection optic disc Gaussian mask updated neighboring differential clustering intensity variation masking retinal image.

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Design of Compact Baugh-Wooley Multiplier Using Reversible Logic

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Circuits and Systems 2016年第8期7卷 1522-1529页

作者： V. Rajmohan O. uma maheswari Department of Electronics and Communication Engineering College of Engineering Chennai India

In today’s digital era, developing digital circuits is bounded by the research towards investigating various nano devices. This paper provides the design of compact Baugh-Wooley multiplier using reversible logic. Even though various researches have been done for designing reversible multiplier, this work is the first in the literature to use Baugh-Wooley algorithm using reversible logic. In this work, a new 5 × 5 reversible multiplier cell is proposed which will be useful in designing Baugh-Wooley multiplier. The proposed single multiplier cell is able to perform addition of a 1 × 1 product with the sum and carry from the previous cell. This reversible multiplier cell is useful in building up regularity in the array multipliers. The Toffoli gate synthesis of the proposed reversible multiplier cell is also given.

关键词： Multiplier Baugh-Wooley Low-Power Reversible Logic Quantum Computer

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A Theoretical Model of pH-Based Potentiometric Biosensor Based on Immobilized Enzyme Membrane

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American Journal of Analytical Chemistry 2016年第4期7卷 363-377页

作者： Jeganathan Saranya Lakshmanan Rajendran Mariappan uma maheswari Department of Mathematics Mother Teresa Women’s University Kodaikanal India Department of Mathematics Sethu Institute of Technology Kariapatti India Department of Mathematics Kamaraj College of Engineering and Technology Virudhunagar India

A theoretical model for the non steady-state response of a pH-based potentiometric biosensor immobilizing organophosphorus hydrolase (OPH) is discussed. The model is based on a system of five coupled nonlinear reaction-diffusion equations under non steady-state conditions for enzyme reactions occurring in potentiometric biosensor that describes the concentration of substrate and hydrolysis products within the membrane. New approximate analytical expressions for the concentration of the substrate (organophosphorus pesticides (OPs)) and products are derived for all values of Thiele modulus and buffer concentration using new approach of homotopy perturbation method. The analytical results are also compared with numerical ones and a good agreement is obtained. The obtained results are valid for the whole solution domain.

关键词： Mathematical Modeling Reaction-Diffusion pH-Based Potentiometric Biosensor Asymptotic Methods New Homotopy Perturbation Method

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Reliability Analysis of a Redundant Cascade System by Using Markovian Approach

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Journal of Applied Mathematics and Physics 2015年第7期3卷 911-920页

作者： Nalabolu Swathi Tallapureddy Sumathi uma maheswari Department of Mathematics Kakatiya University Warangal India

In the present work, it is assumed that the n-components are arranged in the hierarchial order. The n-cascade system surviving with loss of m components by k number of attacks is studied;the general equation for the reliability is obtained for the above said system;and the system reliability is computed numerically for 6-cascade system for 2-number of attacks.

关键词： Cascade System Redundancy Reliability Markov Process k Attacks

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Phytosociology of stratification in a lowland tropical rainforest occurring north of the Tropic of Cancer in Meghalaya, India

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Plant Diversity 2019年第5期41卷 285-299页

作者： uma Shankar Department of Botany North-Eastern Hill University

Stratification in lowland rainforests of Meghalaya,India,which represent the westernmost limit of the rainforests north of the Tropic of Cancer,was studied in horizontal and vertical planes to elucidate the patterns in stacking of species diversity and community attributes,and to draw comparisons with rainforests of‘Indo-Malaya’ecozone(biogeographical realm).All individuals≥10 cm GBH(girth at breast height)were enumerated in six transects of 10 m width and up to 500 m length covering 2.45 ha *** stratification of whole assemblage of species in vertical plane is referred to as‘storey structure’(=height class distribution),which explains structural *** horizontal plane,it is typically referred to as‘stand structure’(=girth class distribution),which explains structural *** stratification of an individual species in vertical plane is referred to as‘loftiness’and in horizontal plane,it is frequently referred to as‘population structure’.The stand structure was characterized by a negative exponential relationship or a reverse J-shaped curve,which is typical of a well regenerating forest *** storey structure was characterized by the low stature of the rainforest(<30 m),subtle layering in the canopy with dearth of discrete multi-stories,narrower widths of the stories and a thick *** cluster analysis and‘candlestick charts’showed that the dominant species spatially segregated in canopy height to profile three strata,viz.,an understory of juveniles and shrubs below 5 m,a middle-storey of intermediate trees between 5 and 15 m,and an overstory of large trees between 15 and 25 *** trees of a few species may reach up to 30 *** individuals tended to scatter in increasingly wider range of height classes from a lower to the next higher girth class,creating a‘torchlight scatter’pattern,with a tendency to concentrate towards smaller height classes due to stochastic factors,which potentially influence vertical growth proportionate t

关键词： Forest stratification Stand structure Storey structure Loftiness Population structure Northeast India

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Concatenated deleting machines and their characteristics

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Communications in Theoretical Physics 2023年第3期75卷 48-55页

作者： A Nancy S balakrishnan Department of Physics School of Advanced SciencesVellore Institute of TechnologyVellore 632014Tamil NaduIndia

In this work,we study the performance of one shot and concatenated deleting machines(DMs).We show that the output state of one shot DMs are mixed inseparable,and do not violate Bell's inequality but can be used as a teleportation channel for all values of the input state *** the other hand,we observe in the concatenation of different DMs that the output states are mixed inseparable and do not violate Bell's inequality,and cannot be used as a teleportation ***,some important attributes such as inseparability,violation of Bell's inequality,and teleportation fidelity of the DMs remain unchanged under the order of *** this context of a teleportation channel,one shot DMs are useful when compared to concatenated DMs.

关键词： Pati-Braunstein deleting machine concatenated deleting machine teleportation fidelity Bell's inequality

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Representations for reliability functions of conditional coherent systems with INID components and ordered properties

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Journal of Systems Engineering and Electronics 2015年第6期26卷 1316-1324页

作者： Zhengcheng Zhang Narayanaswamy balakrishnan School of Mathematics and Physics Lanzhou Jiaotong University Department of Mathematics and Statistics Mc Master University

This paper presents several useful mixture representations for the reliability function of the residual live of a coherent system with independent but non-identically distributed components. These presentations are based on order statistics, signatures and mean reliability functions. We then discuss some stochastic comparisons of residual lives between two systems based on the stochastic ordering of coefficient vectors （or components） of the two systems. These results form nice extensions of some known results for the case of independent and identically distributed components.

关键词： mixture independent but non-identically distributed(INID) stochastic order signature residual life mean reliabilityfunction order statistics.

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