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Hepatoprotective effect of Averrhoea carambola fruit extract on carbon tetrachloride induced hepatotoxicity in mice

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Asian Pacific Journal of Tropical Medicine 2010年第8期3卷 610-613页

作者： A.k.Azeem Molly Mathew Chandraniohan Nair Dilip.C Al Shifa College of Pharmacy Poonthavanam P.OKizhatturPerinlhalmannaMalappuram DistKerala.India 679329 Malik Deenar College of Pharmacy KasaragodKerala Al Shifa College of Pharmacy Poonlhavaimm P.O.KizhatlurPerinthalmannaMalappuram DistKerala.India 679329

Objective:To investigate the hepatoprotective activity of Averroha carambola fruit extract against carbon tetrachloride induced hepatic ***:Hepatotoxicity was induced on albino mice by intraperitoneal administration of CCl4.half an hour after the administration of the last dose of the extract of Averroha carambola *** extract of the fruit of Averroha carambola was administered at a dose of 0.9 g/kg body weight once daily for seven *** hepatic injury and its prevention was assessed by the estimation of serum activities of alanine aminotransferase（ALT）,aspartate aminotransferase（AST）,alkaline phosphates（ALP）,glutathione level and histopathological studies of ***:Pre-treatment of mice with the fruit extract of Averrhoea carambola significantly reduced serum levels of ALT,AST and ALP enzyme and significantly increased the liver reduced glutathione levels 24 h after the administration of carbon tetrachloride.A marked improvement in the enzyme activities and the liver reduced glulathione level was observed in the pre-treated mice 4 days after the administration of carbon tetrachloride. Histopathological studies provided supportive evidence for the biochemical analvsis. Conclusions:The aqueous extract of the fruit of Averrhoea carambola has hepatoprotective effect against carbon tetrachloride induced liver damage in mice.

关键词： Averroha carambola Aqueous extract Hepatoprotective activity Carbon tetrachloride

Load balancing in cloud environs:Optimal task scheduling via hybrid algorithm

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International Journal of Modeling, Simulation, and Scientific Computing 2021年第2期12卷 40-65页

作者： Shashikant Raghunathrao Deshmukh S.k.Yadav D.N.kyatanvar Shri JJT University ChudelaJhunJhunuRajasthanIndia

In cloud computing,a lot of challenges like the server failures,loss of confidentiality,improper workloads,*** still bounding the efficiency of cloud systems in real-world *** this reason,many research works are being performed to overcome the shortcoming of existing *** them,load balancing seems to be the most critical issue that worsen the performance of the cloud sector,and hence there necessitates the optimal load balancing with optimal task *** the intention of accomplishing optimal load balancing by effectual task deployment,this paper plans to develop an advanced load balancing model with the assistance acquired from the metaheuristic ***,handling of tasks in cloud system is an NP-hard problem and moreover,nonpreemptive independent tasks are crucial in cloud *** paper goes with the introduction of a new optimal load balancing model by considering three major objectives:minimum makespan,priority,and load balancing,***,a new single-objective function is also defined that incorporates all the three objectives mentioned ***,the deployment of tasks must be optimal and for this a new hybrid optimization algorithm referred as Firefly Movement insistedWOA(FM-WOA)is *** FM-WOA is the conceptual amalgamation of standard Whale Optimization Algorithm(WOA)and Firefly(FF)***,the performances of the proposed FM-WOA model is compared over the conventional models with the intention of proving its efficiency in terms of makespan,task completion(priority),and degree of imbalance as well.

关键词： Cloud computing load balancing task scheduling whale optimization algorithm firefly algorithm

Design of Finite Element Tools for Coupled Surface and Volume Meshes

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Numerical Mathematics(Theory,Methods and Applications) 2008年第3期1卷 245-274页

作者： Daniel kster Oliver kriessl kunibert G.Siebert Numerical Analysis and Computational Mechanics Group University of TwenteP O.Box 2177500 AE EnschedeThe Netherlands. Institut für Mathematik Universitt AugsburgUniversittsstraβe 14D-86159 AugsburgGermany.

Many problems with underlying variational structure involve a coupling of volume with surface effects.A straight-forward approach in a finite element discretiza- tion is to make use of the surface triangulation that is naturally induced by the volume *** an adaptive method one wants to facilitate'matching'local mesh modifications,i.e.,local refinement and/or coarsening,of volume and surface mesh with standard tools such that the surface grid is always induced by the volume grid. We describe the concepts behind this approach for bisectional refinement and describe new tools incorporated in the finite element toolbox *** also present several important applications of the mesh coupling.

关键词： Adaptive finite element methods scientific software software design.

Large pore size polyacrylonitrile membrane for ultrafiltration

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Journal of Environmental Sciences 2000年第4期12卷 478-481页

作者： Wu, k. Qiu, P. Wang, Z. Wang, J. Rsrch. Center for Eco-Envtl. Sci. Chinese Academy of Sciences Beijing 100085 China

The effects of the components of solution for membrane casting and preparation conditions on the membrane performances are studied in this paper. Polyacrylonitrile (PAN) was used as polymer and DMAC as solvent. The ultrafiltration (UF) membranes whose cut-off of molecular weight is 150000 and flux of pure water reaches 150-200 ml/(cm2·h) were prepared by selecting proper components of solution for membrane casting and membrane preparation conditions.

关键词： Casting Molecular weight Polyacrylonitriles Pore size Water quality

Repeatability of two-dimensional chemical shift imaging multivoxel proton magnetic resonance spectroscopy for measuring human cerebral choline-containing compounds

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World Journal of Psychiatry 2018年第1期8卷 20-26页

作者： Basant k Puri Mary Egan Fintan Wallis Philip Jakeman Department of Medicine Hammersmith HospitalImperial College London Department of Radiology University Hospital Limerick Centre for Interventions in Infection Inflammation and Immunity University of Limerick

AIM To investigate the repeatability of proton magnetic resonance spectroscopy in the in vivo measurement of human cerebral levels of choline-containing compounds(Cho).METHODS Two consecutive scans were carried out in six healthy resting subjects at a magnetic field strength of 1.5 T. On each occasion, neurospectroscopy data were collected from 64 voxels using the same 2 D chemical shift imaging(CSI) sequence. The data were analyzed in the same way, using the same software, to obtain the values for each voxel of the ratio of Cho to creatine. The Wilcoxon related-samples signed-rank test, coefficient of variation(CV), repeatability coefficient(RC), and intraclass correlation coefficient(ICC) were used to assess the repeatability. RESULTS The CV ranged from 2.75% to 33.99%, while the minimum RC was 5.68%. There was excellent reproducibility, as judged by significant ICC values, in 26 voxels. Just three voxels showed significant differences according to the Wilcoxon related-samples signed-rank test. CONCLUSION It is therefore concluded that when CSI multivoxel proton neurospectroscopy is used to measure cerebral choline-containing compounds at 1.5 T, the reproducibility is highly acceptable.

关键词： Cerebral metabolites Chemical shift imaging Choline Neurospectroscopy Neuropsychiatric disorders

Limitations in tracking systems

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控制理论与应用（英文版） 2010年第3期8卷 351-358页

作者： Ivan Lopez HURTADO Chaouki T.ABDALLAH Sudharman k.JAYAWEERA Department of Engineering Northern New Mexico College Department of Electrical & Computer Engineering University of New Mexico

In this paper, we obtain information theoretical conditions for tracking in linear time-invariant control systems. We consider the particular case where the closed loop contains a channel in the feedback loop. The mutual information rate between the feedback signal and the reference input signal is used to quantify information about the reference signal that is available for feedback. This mutual information rate must be maximized in order to improve the tracking performance. The mutual information is shown to be upper bounded by a quantity that depends on the unstable eigenvalues of the plant and on the channel capacity. If the channel capacity reaches a lower limit, the feedback signal becomes completely uncorrelated with the reference signal, rendering feedback useless. We also find a lower bound on the expected squared tracking error in terms of the entropy of a random reference signal. We show a misleading case where the mutual information rate does not predict the expected effect of nonminimum phase zeros. However, mutual information rate helps generalize the concept that there is a tradeoff when tracking and disturbance rejection are simultaneous goals, and a constraint communication channel is present in the feedback loop. Examples and simulations are provided to demonstrate some of the results.

关键词： Limited channel capacity Tracking systems Constraint feedback

Cobalt Schiff base complexes: Synthesis characterization and catalytic application in Suzuki–Miyaura reaction

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Chinese Journal of Chemical Engineering 2019年第3期27卷 556-563页

作者： Rasheeda M.Ansari Lolakshi k.Mahesh Badekai Ramachandra Bhat Department of Chemistry Catalysis and Material Chemistry Laboratory National Institute of Technology Karnataka

3-Methoxysalicylaldehyde was condensed with the amines 4-aminoacetophenone and 2-amino-5-bromopyridine to obtain Schiff base ligands, 1 and 2, which were coordinated to cobalt salts as complex 1 and complex 2, respectively. The synthesized ligands and complexes were characterized by spectroscopic(FT-IR,UV–Vis,~1H-NMR and mass spectrometry), thermal(TGA) and elemental analysis. The structures of the complexes were verified by evaluating their magnetic susceptibility and spectroscopic evidences. Synthesized complexes were studied for their catalytic activity in the Suzuki–Miyaura cross-coupling of aryl halides with phenylboronic acid. Optimized reaction yields 90% of the cyanobiphenyl for complex 1 and 91% for complex 2 with 0.1 mmol of catalyst loading thereby substantiating the C\\C coupling efficiency of the synthesized complexes, 1 and 2.

关键词： Transition metal complex Schiff base Suzuki-Miyaura coupling reaction Cobalt

Effective data sampling strategies and boundary condition constraints of physics-informed neural networks for identifying material properties in solid mechanics

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Applied Mathematics and Mechanics(English Edition) 2023年第7期44卷 1039-1068页

作者： W.WU M.DANEkER M.A.JOLLEY k.T.TURNER L.LU Department of Anesthesiology and Critical Care Medicine Children's Hospital of PhiladelphiaPhiladelphiaPA 19104U.S.A. Division of Pediatric Cardiology Children's Hospital of PhiladelphiaPhiladelphiaPA 19104U.S.A. Department of Chemical and Biomolecular Engineering University of PennsylvaniaPhiladelphiaPA 19104U.S.A. Department of Mechanical Engineering and Applied Mechanics University of PennsylvaniaPhiladelphiaPA 19104U.S.A.

Material identification is critical for understanding the relationship between mechanical properties and the associated mechanical ***,material identification is a challenging task,especially when the characteristic of the material is highly nonlinear in nature,as is common in biological *** this work,we identify unknown material properties in continuum solid mechanics via physics-informed neural networks(PINNs).To improve the accuracy and efficiency of PINNs,we develop efficient strategies to nonuniformly sample observational *** also investigate different approaches to enforce Dirichlet-type boundary conditions(BCs)as soft or hard ***,we apply the proposed methods to a diverse set of time-dependent and time-independent solid mechanic examples that span linear elastic and hyperelastic material *** estimated material parameters achieve relative errors of less than 1%.As such,this work is relevant to diverse applications,including optimizing structural integrity and developing novel materials.

关键词： solid mechanics material identification physics-informed neural network(PINN) data sampling boundary condition(BC)constraint

Genetic-based Fuzzy IDS for Feature Set Reduction and Worm Hole Attack Detection

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Computer Systems Science & Engineering 2023年第5期45卷 1265-1278页

作者： M.Reji Christeena Joseph k.Thaiyalnayaki R.Lathamanju Department of Electronics and Communication Engineering Rohini College of Engineering and TechnologyPalkulamKanyakumariIndia Department of Electronics and Communication Engineering SRM Institute of Science and TechnologyRamapuramChennaiIndia

The wireless ad-hoc networks are decentralized networks with a dynamic topology that allows for end-to-end communications via multi-hop routing operations with several nodes collaborating themselves,when the destination and source nodes are not in range of *** of its wireless type,it has lot of security concerns than an infrastructure *** attacks are one of the most serious security vulnerabilities in the network *** is simple to launch,even if there is no prior network *** are the sole thing that preventive measures rely *** detection systems(IDS)and other reactive measures detect all types of *** majority of IDS employ features from various network *** issue is calculating a huge layered features set from an ad-hoc *** research implements genetic algorithm(GA)-based feature reduction intrusion detection approaches to minimize the quantity of wireless feature sets required to identify worm hole *** attack detection,the reduced feature set was put to a fuzzy logic system(FLS).The performance of proposed model was compared with principal component analysis(PCA)and statistical parametric mapping(SPM).Network performance analysis like delay,packet dropping ratio,normalized overhead,packet delivery ratio,average energy consumption,throughput,and control overhead are evaluated and the IDS performance parameters like detection ratio,accuracy,and false alarm rate are evaluated for validation of the proposed *** proposed model achieves 95.5%in detection ratio with 96.8%accuracy and produces very less false alarm rate(FAR)of 14%when compared with existing techniques.

关键词： Intrusion detection system wormhole attack genetic algorithm fuzzy logic wireless ad-hoc network