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Genetic variation in the chemokine receptor 5 gene and course of HIV infection;review on genetics and immunological aspect

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Genes & Diseases 2021年第4期8卷 475-483页

作者： m.K.Verma S.Shakya Department of Biotechnology Acharya Nagarjuna UniversityNagarjuna NagarGunturAndhra Pradesh522510India Indian Institute of Technology Indore IndoreMadhya Pradesh453552India

Chemokines are small protein molecules associated with various physiological events precisely in immune modulation via dhemokine *** chemokine receptors are G-protein coupled receptors express mainly on the cell surface of immune ***-ruses,including HIV in the early stage of infection,primarily target chemokines receptors and get intemalized easily into immune cells;T cell and escape from immune *** glycoprotein selectively develops an affinity for the extracellular domain of chemokines recep-tors and allows the pathogen to intemalize via ***,CCR-5 remains a crucial signaling pathway that can be translated into the therapeutic target by changing the receptor protein *** populations have a mutation in coding and promoter regions of CCR-5,tun-ing a resistance for HIV ***,there are several mechanisms where the human genome remains in the dynamic state by changing its composition and acquiring ***-gle nucleotide polymorphism is spontaneous phenomenon responsible for precise and point mutation at the *** studies have demonstrated that European and African Amer-ican populations are enriched in significant CCR5 promoter SNP(CCR5432)in the coding and promoter region as ***,such SNP can be an early-stage biomarker in studying HIV and other similar ***,in this study,we have elucidated the role of SNP(both the pro-moter and coding region)and the fate of HIV *** also empathized with the genetics of such SNPs,mostly frequency and its immunological impact.

关键词： Acquired immunodeficiency syndrome Chemokine and chemokine receptors Human immune deficiency viruses Single nucleotide polymorphism

mechanisms behind the environmental sensitivity of carbon fiber reinforced polytetrafluoroethylene(PTFE)

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Friction 2024年第5期12卷 997-1015页

作者： Pontus JOHANSSON P.mARKLUND m.BJORLING Y.SHI Division of machine Element LuleåUniversity of TechnologyLuleåSE-97187Sweden

Carbon fiber reinforced polytetrafluoroethylene (CF/PTFE) composites are known for their exceptional tribological performance when sliding against steel or cast iron in inert gas environments. Compared to experiments in humid air, about an order of magnitude lower wear rate and several times lower coefficient of friction have been reported for tests conducted in dry nitrogen and hydrogen. moreover, trace moisture has been shown to affect the friction and wear significantly of this tribosystem, although a possible effect of oxygen cannot be ruled out due to uncertainties regarding the oxygen concentrations. While several studies have pointed out the environmental sensitivity of CF/PTFE, the understanding of the underlying mechanisms are very limited. The objective of this research is to investigate the individual and combined effect of oxygen and moisture on the tribological behavior of CF/PTFE sliding against steel. Additionally, this study aims to elucidate the underlying mechanisms that govern the environmental sensitivity of the system. Climate-controlled three-pin-on-disc experiments were conducted in nitrogen atmospheres at various concentrations of oxygen and moisture. The tribological results clearly demonstrate that both moisture and oxygen contribute to increased friction and wear. However, the adverse effect was much more pronounced for oxygen than moisture. A qualitative method was developed to estimate the tribofilm coverage on the CF/PTFE surface. Results showed strong correlation between high coverage of strongly adhered tribofilm and low wear rate. moreover, a loosely adhered tribofilm was observed on top of the CF/PTFE surface in presence of moisture. FTIR analysis indicated that the loosely adhered tribofilm found in the moisture-enriched environment contained a significant amount of adsorbed water, which may explain the lower coefficient of friction in presence of moisture compared to oxygen. The adsorbed water in the loosely adhered tribofilm coul

关键词： polymer composite tribofilm tribochemistry atmosphere

On Regularization of a Source Identification Problem in a Parabolic PDE and its Finite Dimensional Analysis

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Journal of Partial Differential Equations 2021年第3期34卷 240-257页

作者： mONDAL Subhankar NAIR m.Thamban Department of mathematics IIT MadrasChennai 600036India

We consider the inverse problem of identifying a general source term,which is a function of both time variable and the spatial variable,in a parabolic PDE from the knowledge of boundary measurements of the solution on some portion of the lateral *** transform this inverse problem into a problem of solving a compact linear operator *** the regularization of the operator equation with noisy data,we employ the standard Tikhonov regularization,and its finite dimensional realization is done using a discretization procedure involving the space L^(2)(0,τ;L^(2)(Ω)).For illustrating the specification of an a priori source condition,we have explicitly obtained the range space of the adjoint of the operator involved in the operator equation.

关键词： Ill-posed source identification Tikhonov regularization weak solution

Enslaved Phase-Separation Fronts and Liesegang Pattern Formation

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Communications in Computational Physics 2011年第5期9卷 1081-1093页

作者： E.m.Foard A.J.Wagner Department of Physics North Dakota State UniversityFargoND 58105USA

We show that an enslaved phase-separation front moving with diffusive speeds U=C/√T can leave alternating domains of increasing size in their *** find the size and spacing of these domains is identical to Liesegang *** equal composition of the components we are able to predict the exact form of the pattern *** our knowledge this is the first fully analytical derivation of the Liesegang *** also show that there is a critical value for C below which only two domains are *** analytical predictions are verified by numerical simulations using a lattice Boltzmann method.

关键词： Liesegang phase separation front reaction diffusion pattern formation lattice Boltzmann matalon-Packter

Bilirubin adsorption property of mesoporous silica and amine-grafted mesoporous silica

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Nano-micro Letters 2009年第1期1卷 14-18页

作者： L.X.Zhang m.Zhu L.m.Guo L.Li J.L.Shi State Key Laboratory of High Performance and Superfine microstructure Shanghai Institute of Ceramics Chinese Academy of Science

Nephritic, hepatic and immune failures would lead to the overload of endogenous toxic molecules(e.g. bilirubin, cholic acid, uric acid, creatinine etc.) in human bodies. It is fatal in most cases and extracorporeal blood purification(ECBP) is powerful first-aid therapy. Adsorbents are key parts of ECBP apparatus. mesoporous silicas should be promising candidates for these medical adsorbents, but there is no report about this. Herein, pure and amine-grafted mesoporous silicas have been applied to adsorb bilirubin, cholic acid, uric acid, creatinine and phenobarbital for the first time. These mesoporous materials show high adsorption capacities for bilirubin and uric acid in phosphate buffer solution(PBS). Effects of pore sizes, amine-modification, temperature and ionic strength on their bilirubin adsorption capacities have been studied in detail.

关键词： mesoporous silica Bilirubin adsorption Amine-grafted

Identification and Selection of Regional Plants withPotential for Phytoremediation in Abandoned Open PitTailing Dams

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Journal of Environmental Science and Engineering(A) 2020年第2期9卷 56-65页

作者： Luis miguel Rodríguez Vázquez Ana Irán Prieto Valles Ramón Silva Vázquez Héctorávalos Loya EduardoHerrera Peraza Emilio Yanez Terrazas Francisco Rueda Ever Ulysses Torres Carrillo Leonor CortésPalacios Gilberto Sandino aquino Department of Chemical Engineering Tecnológico Nacional de México-Instituto Tecnológico de ParralHidalgo del ParralChihuahua 33850México Department of Renewable Energies and Environmental Protection Centro de Investigación en Materiales AvanzadosS.C.ChihuahuaChihuahua 31109México Faculty of Zootechnics and Ecology Universidad Autónoma de Chihuahua(UACH)ChihuahuaChihuahua 31000México

The degree of adaptability and phytoremediation potential of the plant species, Zacate Garrapata, Zacate Banderita, Chivatillo, Oregano, Chamizo and Sotol were evaluated on different substrates (S) composed of tailing (Jm) and agricultural land (TA) in different proportions in mass: S1 = 100% TA, S2 = 100% Jm, S3 = 50% TA and 50 % Jm, S4 = 25% Jm and 75% TA, S5 = 75% Jm and 25% TA. With the combination of species and substrates, 30 treatments were generated. The heavy metals evaluated were Pb, As, Cu. Fe, Cr and Zn, in root, leaf and stem. The results showed significant statistical differences (p mulation of heavy metals in interaction with S3. These two species can be used in the remediation of open pit tailing dam.

关键词： Adaptability plant species substrate mix heavy metals abandoned tailing dams

Efficient Crack Severity Level Classification Using Bilayer Detection for Building Structures

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Computer Systems Science & Engineering 2023年第7期46卷 1183-1200页

作者： m.J.Anitha R.Hemalatha Department of Electronics and Communication Engineering Central Polytechnic CollegeChennai600113India Department of Electronics and Communication Engineering Sri Sivasubramaniya Nadar College of EngineeringChennai603110India

Detection of cracks at the early stage is considered as very constructive since precautionary steps need to be taken to avoid the damage to the civil ***,identifying and classifying the severity level of cracks is inevitable in order to find the stability of ***,this paper proposes an efficient strategy to classify the cracks into fine,medium,and thick using a novel bilayer crack detection *** bilayer crack detection algorithm helps in extracting the requisite features from the crack for efficient *** proposed algorithm works well in the dark background and connects the discontinued cracks *** first layer is used to detect cracks under texture variations and manufacturing defects,through segmented adaptive thresholding and morphological *** residual noise present in the output of the first layer is removed in the second layer of crack *** second layer includes the double scan and the noise reduction algorithms and is used to join the missed crack *** a result,a segmented crack is *** classification is done using an ensemble classifier with bagging,and decision tree techniques by extracting the geometrical features and the weaker crack criterion from the segmented *** results of the proposed technique are compared with the existing techniques for different datasets and have obtained a rise in True Positive Rate(TPR),accuracy and precision *** proposed technique is also implemented in Raspberry Pi for further real-time evaluation.

关键词： Crack detection image processing adaptive thresholding emeasure accuracy classifier

Tripolye mega-Sites:“Collective Computational Abilities”of Prehistoric Proto-Urban Societies?

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Journal of Social Computing 2022年第1期3卷 75-90页

作者： Johannes müller Robert Hofmann mila Shatilo the Institute of Prehistoric and Protohistoric Archaeology Kiel UniversityKiel 24106Germany

In the East European region between Prut and Dnieper,proto-urban mega-sites developed ca.4100−3600 BCE with population agglomerations of around 10000 inhabitants per *** outline of complexity categories,based on *** et al.(2018),illustrates that“computational abilities”are first developed to make the shift from dispersed to agglomerated settlement *** development of an internal decision-making system for a polity that organizes communication via public buildings on different levels,together with a site-specific track system,may be responsible for this shift(or made it possible).However,after generations,this communication pattern was not developed into further collective communication abilities(e.g.,into a writing system),while at the same time a tendency toward centralizing decision processes probably destroyed the communication *** ultimately led to the collapse of Tripolye mega-sites.

关键词： non-state societies social constitution Chalcolithic mega-sites Tripolye

Effect of Combined Chilling and GA_3 Treatment on Bud Abortion in Forced ‘Luoyanghong' Tree Peony(Paeonia suffruticosa Andr.)

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Horticultural Plant Journal 2018年第6期4卷 250-256页

作者： mORNYA Philip m.P. CHENG Fangyun National Flower Engineering Research Center College of Landscape Architecture Beijing Forestry University School of Natural Resources management Njala University National Flower Engineering Research Center College of Landscape ArchitectureBeijing Forestry University

This research investigated the effect of combined chilling and GA_3 treatment on bud abortion of tree peony under greenhouse conditions to determine the dynamics of exogenous hormones and chilling effects on bud abortion. Research of such nature will increase the understanding of the effects of GA_3 and chilling level on flower development thereby, promoting off-season cultivation techniques in tree peonies to increase production that meets market demand. Hormone and sugar levels in the ‘Luoyanghong' tree peony were respectively determined using High-Performance Liquid Chromatography(HPLC) and spectrophotometer. Non-potted chilling with 200 mg·L^(-1) GA_3 treatment reduced bud abortion rate. Flowering rate in non-potted chilling with 200 mg·L^(-1) GA_3 plants was 58%, as against 21% in potted chilling plants with 200 mg·L^(-1) GA_3 treatment. Sugar accumulation in retained or aborted flower buds was conversely related to ABA level. Low ABA and high sugar levels were noted in retained buds whereas the reverse induced bud abortion. ABA level apparently inhibited sucrose and reducing sugar uptake in aborted buds whereas GA_3 enhanced sucrose uptake in retained buds. GA_3 and IAA levels were higher in retained than in aborted buds, which made plants with retained bud more competitive in nutrient uptake(by root)for growth and development. Overall, combined chilling and GA_3 treatment enhanced plant growth and development, particularly bud sprouting, growth and flowering.

关键词： tree peony bud abortion chilling hormone sugar GA3 ABA IAA