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Advances in Bioscience and Biotechnology 2013年第5期4卷 623-627页

作者： Barkur s. shastry Department of Biological sciences Oakland University Rochester USA

Glaucoma is an optic neuropathy and often associated with elevated intraocular pressure (IOP). It is the second leading cause of irreversible blindness worldwide and is characterized by the optic nerve degeneration and loss of retinal ganglion cells (RGCs). This may lead to loss of vision. The primary cause of glaucoma is unknown but several risk factors including elevated IOP and age have been suggested. In most population, primary open-angle glaucoma (POAG) is the most common type of glaucoma and is often associated with elevated IOP. Genetic analyses have identified at least 14 chromosomal loci but only three genes which when mutated can cause POAG have been well documented. These genes account for less than 5% of all POAG cases suggesting that more than 90% of the genetic contribution of POAG cases is unknown. RGC consists of cell body, axon and dendritic arbor and each of these three parts can independently degenerate. several molecular signals such as oxidative stress, mitochondrial dysfunction, disruption of neurotrophic factor (NTF), dysfunction of immune system, glial activation and the release of tumor necrosis factor (TNF) have been found to be involved in the optic nerve degeneration. Therefore, therapies aimed at axonal and cell body protection may have a greater protective role in early or progressive glaucoma. In the future, an understanding of gene-gene and gene-environmental factor interaction as well as epigenetic regulation of gene expression by environmental factors may provide an opportunity to develop neuroprotective therapies and DNA based diagnostic tests.

关键词： Degeneration Gene Mutation Retina

AC measurements of spray-deposited Cds:In thin films

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Journal of Central south University 2012年第3期19卷 829-834页

作者： s.J.Ikhmayies R.N.Ahmad-Bitar Department of Basic sciences-Physics Faculty of Information TechnologyAl Isra University Physics Department Faculty of ScienceUniversity of Jordan

Indium doped cadmium sulfide thin films （Cds：In） were produced by the spray pyrolysis technique on glass substrates. AC measurements were used to investigate the electrical properties of the films depending on Brick-layer model for polycrystalline materials. The measurements were performed at room temperature in the dark and room light in the frequency range from 20 Hz to 1 MHz using coplanar indium electrodes. The data were analyzed by using Bode plots for the impedance Z and dielectric loss tang with frequencyf It is found that the impedance has no dependence on frequency in the low frequency region but has 1/f dependence in the high frequency region. One dielectric loss peak is obtained, which means the presence of a single relaxation time, and hence the films are modeled by just one RC circuit which represents the grains. This means that there is just one conduction mechanism that is responsible for the conduction in the bulk, due to electronic transport through the grains. Real values of the impedance in the low frequency region and relaxation times for treated and as-deposited fihns were estimated.

关键词： II-VI compounds spray pyrolysis impedance dielectric loss Bode plots

On the Boundary Behaviour,Including second Order Effects,of solutions to singular Elliptic Problems

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Acta Mathematica sinica,English series 2007年第3期23卷 479-486页

作者： s.BERHANU F.CUCCU G.PORRU Department of Mathematics Temple UniversityPhiladelphiaPA 19122USA Dipartimento di Matematica e Informatica University of Cagliarivia Ospedale 72 09124 CagliariItaly

For γ≥1 we consider the solution u=u（x） of the Dirichlet boundary value problem Δu ＋ u^-γ=0 in Ω, u=0 on δΩ. For γ= 1 we find the estimate u（x）=p（δ（x））[1＋A（x）（log 1/δ（x）^-6],where p（r） ≈ r r√2 log（1/r） near r = 0,δ（x） denotes the distance from x to δΩ, 0 〈ε 〈 1/2, and A（x） is a bounded function. For 1 〈 γ 〈 3 we findu（x）=（γ＋1/√2（γ-1）δ（x））^2/γ＋[1＋A（x）（δ（x））2γ-1/γ＋1]For γ3= we prove thatu（x）=（2δ（x））^1/2[1＋A（x）δ（x）log 1/δ（x）]

关键词： elliptic problems singular equations boundary behaviour

Analysis of sampling Error Uncertainties and Trends in Maximum and Minimum Temperatures in China

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Advances in Atmospheric sciences 2014年第2期31卷 263-272页

作者： HUA Wei samuel s.P.sHEN WANG Huijun Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Department of Atmospheric sciences Chengdu University of Information Technology University of the Chinese Academy of sciences Department of Mathematics and statistics San Diego State University

In this paper we report an analysis of sampling error uncertainties in mean maximum and minimum temperatures （Tmax and Tmin） carried out on monthly,seasonal and annual scales,including an examination of homogenized and original data collected at 731 meteorological stations across China for the period *** of the gridded data and national average,linear trends and their uncertainties,as well as the homogenization effect on uncertainties are *** is shown that the sampling error variances of homogenized Tmax and Tmin,which are larger in winter than in summer,have a marked northwest-southeast gradient distribution,while the sampling error variances of the original data are found to be larger and *** and Tmin increase in all months of the year in the study period 1951-2004,with the largest warming and uncertainties being 0.400℃ （10 yr）-1 ＋ 0.269℃ （10 yr）-1 and 0.578℃ （10 yr）-1 ＋ 0.211℃ （10 yr）-1 in February,and the least being 0.022℃ （10 yr）-1 ＋ 0.085℃ （10 yr）-1 and 0.104℃ （10 yr）-1 ＋0.070℃ （10 yr）-1 in *** can remove large uncertainties in the original records resulting from various non-natural changes in China.

关键词： sampling error uncertainty maximum temperature minimum temperature temperature trend

Copy-Move Forgery Verification in Images Using Local Feature Extractors and Optimized Classifiers

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Big Data Mining and Analytics 2023年第3期6卷 347-360页

作者： s.B.G.Tilak Babu Ch srinivasa Rao University College of Engineering JNTU KakinadaKakinada 533003India. Department of ECE JNTUK UCEVizianagaram 535003India.

Passive image forgery detection methods that identify forgeries without prior knowledge have become a key research *** copy-move forgery,the assailant intends to hide a portion of an image by pasting other portions of the same *** detection of such manipulations in images has great demand in legal evidence,forensic investigation,and many other *** paper aims to present copy-move forgery detection algorithms with the help of advanced feature descriptors,such as local ternary pattern,local phase quantization,local gabor binary pattern histogram sequence,Weber local descriptor,and local monotonic pattern,and classifiers such as optimized support vector machine and optimized *** proposed algorithms can classify an image efficiently as either copy-move forged or authenticated,even if the test image is subjected to attacks such as JPEG compression,scaling,rotation,and brightness ***,CAsIA,and MICC datasets and a combination of CoMoFoD and CAsIA datasets images are used to quantify the performance of the proposed *** proposed algorithms are more efficient than state-of-the-art algorithms even though the suspected image is post-processed.

关键词： copy move forgery detection image authentication passive image forgery detection blind forgery detection

Review of stochastic optimization methods for smart grid

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Frontiers in Energy 2017年第2期11卷 197-209页

作者： s. surender REDDY Vuddanti sANDEEP Chan-Mook JUNG Department of Railroad and Electrical Engineering Woosong Uni-versity Republic of Korea school of Engineering Central University of Kamataka India Department of Railroad and Civil Engineering Woosong UniversityRepublic of Korea

This paper presents various approaches used by researchers for handling the uncertainties involved in renewable energy sources, load demands, etc. It gives an idea about stochastic programming (sP) and discusses the formulations given by different researchers for objective functions such as cost, loss, generation expansion, and voltage/V control with various conventional and advanced methods. Besides, it gives a brief idea about sP and its applications and discusses different variants of sP such as recourse model, chance constrained programming, sample average approximation, and risk aversion. Moreover, it includes the application of these variants in various power systems. Furthermore, it also includes the general mathematical form of expression for these variants and discusses the mathematical description of the problem and modeling of the system. This review of different optimization techniques will be helpful for smart grid development including renewable energy resources (RERs).

关键词： renewable energy sources stochastic optimization smart grid uncertainty optimal power flow (OPF)

Improvisation of Node Mobility Using Cluster Routing-based Group Adaptive in MANET

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Computer systems science & Engineering 2023年第3期44卷 2619-2636页

作者： J.shanthini P.Punitha s.Karthik Department of Computer science&Engineering Dr.N.G.P.Institute of EngineeringCoimbatoreTamilnaduIndia Department of Computer science&Engineering SNS College of TechnologyCoimbatoreTamilnaduIndia

In today's Internet routing infrastructure,designers have addressed scal-ing concerns in routing constrained multiobjective optimization problems examining latency and mobility concerns as a secondary *** tactical Mobile Ad-hoc Network(MANET),hubs can function based on the work plan in various social affairs and the internally connected hubs are almost having the related moving standards where the topology between one and the other are tightly coupled in steady support by considering the touchstone of hubs such as a self-sorted out,self-mending and *** in the routing process is one of the key aspects to increase MANET performance by coordinat-ing the pathways using multiple criteria and *** present a Group Adaptive Hybrid Routing Algorithm(gaHRA)for gathering portability,which pursues table-driven directing methodology in stable accumulations and on-request steering strategy for versatile *** on this aspect,the research demonstrates an adjustable framework for commuting between the table-driven approach and the on-request approach,with the objectives of enhancing the out-put of MANET routing computation in each *** analysis and replication results reveal that the proposed method is promising than a single well-known existing routing approach and is well-suited for sensitive MANET applications.

关键词： Diplomatic mobile Ad-hoc network grouping mobility interior stable hybrid routing scheme adaptive switch structure clustering communication

A New Computational Approach for solving Optimal Control of Linear PDEs Problem

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Acta Mathematicae Applicatae sinica 2014年第3期30卷 735-748页

作者： M.Mahmoudi A.V.Kamyad s.Effati Department of Mathematics University of Qom Department of Mathematics Ferdowsi University of Mashhad

In this paper, we present a new computational approach for solving an internal optimal control problem, which is governed by a linear parabolic partial differential equation. Our approach is to approximate the PDE problem by a nonhomogeneous ordinary differential equation system in higher dimension. Then, the homogeneous part of ODEs is solved using semigroup theory. In the next step, the convergence of this approach is verified by means of Toeplitz matrix. In the rest of the paper, the optimal control problem is solved by utilizing the solution of homogeneous part. Finally, a numerical example is given.

关键词： optimal control parabolic partial differential equation semigroups theory, nonlinear programming Toeplitz matrix

Roles of computational modelling in understanding p53 structure, biology, and its therapeutic targeting

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Journal of Molecular Cell Biology 2019年第4期11卷 306-316页

作者： Yaw sing Tan Yasmina Mhoumadi Chandra s. Verma Bioinformatics Institute Agency for Science Technology and Research Singapore 138671 school of Biological sciences Nanyang Technological University Singapore 637551 Department of Biological sciences National University of Singapore Singapore 117543

The transcription factor p53 plays pivotal roles in numerous biological processes, including the suppression of tumours. The rich availability of biophysical data aimed at understanding its structure–function relationships since the 1990s has enabled the application of a variety of computational modelling techniques towards the establishment of mechanistic models. Together they have provided deep insights into the structure, mechanics, energetics, and dynamics of p53. In parallel, the observation that mutations in p53 or changes in its associated pathways characterize several human cancers has resulted in a race to develop therapeutic modulators of p53, some of which have entered clinical trials. This review describes how computational modelling has played key roles in understanding structural-dynamic aspects of p53, formulating hypotheses about domains that are beyond current experimental investigations, and the development of therapeutic molecules that target the p53 pathway.

关键词： p53 structure computational modelling therapeutic targeting

Novel typology of accelerated carbonation curing:using dry and pre-soaked biochar to tune carbon capture and mechanical properties of cementitious mortar

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Biochar 2023年第1期5卷 621-640页

作者： H.W.Kua s.M.H.Tan Department of the Built Environment College of Design and EngineeringNational University of SingaporeSingaporeSingapore

One of the challenges of promoting accelerated carbonation curing(ACC)of concrete as a carbon sequestration strategy is ensuring that carbonation will not deteriorate mechanical *** study examined the mechanical strength,water sorptivity and carbonation efficiency of ten types of mortar containing dry or pre-soaked biochar subjected to internal and/or external *** results obtained enabled a typology of ACC to be proposed,in which the carbon dioxide absorption of mortar containing various types of CO_(2)-dosed biochar ranged between 0.022%and 0.068%per unit dosage *** particular,the mortar containing dry biochar dosed with carbon dioxide was the top candidate for concurrently increasing both compressive strength(54.9 MPa)and carbon dioxide absorption(0.055%per unit dosage hour).Mortar containing pre-soaked biochar dosed with carbon dioxide was identified as a strategy that achieved the highest carbonation efficiency(0.068%per unit dosage hour),but it also reduced compressive strength(45.1 MPa).Collectively,the proposed typology offers a useful overview of the different ways by which biochar can be used to tune ACC in mortar,according to any technical constraints and/or intended functions of the carbonated concrete components.

关键词： Biochar Pre-soaked Carbonation effectiveness Carbonation efficiency Accelerated carbonation curing