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Evaluation of antioxidants and argpyrimidine in normal and cataractous lenses in north Indian population

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International Journal of Ophthalmology(English edition) 2017年第7期10卷 1094-1100页

作者： Bharani K Mynampati sujata ghosh Thungapathra Muthukumarappa Jagat ram Department of Ophthalmology Advanced Eye CenterPost Graduate Institute of Medical Education and Research Department of Experimental Medicine & Biotechnology Post Graduate Institute of Medical Education and Research Department of Biochemistry Post Graduate Institute of Medical Education and Research

AIM： To assess the level of glutathione, thioltransferase, and argpyrimidine in nuclear and cortical cataractous lenses as well as in the clear lenses in the north Indian ***： Human cataractous lenses were collected from the patients who underwent extracapsular cataract extraction surgery; clear lenses were collected from the freshly donated eye bank eyes. Antioxidant molecules such as glutathione and thioltransferase enzyme activity were measured; simultaneously in these lenses a blue fluorophore argpyrimidine, an advanced glycation end（AGE） product level was assessed using high performance liquid chromatography（HPLC）.REsULTs： The protein concentration was found to be present at higher levels in the control lenses compared to cataract lenses. A significant decrease in the glutathione level was observed in the nuclear cataractous lenses compared to cortical cataractous（P=0.004） and clear lenses（P≤0.005）, but no significant change in the level of antioxidant enzyme thioltransferase was observed. Further, argpyrimidine a blue fluorophore（AGE） was found to be significantly higher in the nuclear cataract（P=0.013） compared to cortical cataract ***： Antioxidants such as glutathione significantly decrease in age-related nuclear and cortical cataract and an AGE, argpyrimidine are present at significantly higher levels in nuclear cataract.

关键词： age-related cataract antioxidants argpyrimidine glutathione nuclear cataract cortical cataract thioltransferase

survivability of freeze-dried probiotic Pediococcus pentosaceus strains Gs4,Gs17 and Lactobacillus gasseri(ATCC 19992)during storage with commonly used pharmaceutical excipients within a period of 120 days

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Asian Pacific Journal of Tropical Biomedicine 2017年第10期7卷 921-929页

作者： Mayur Bagad ram Pande Vinay Dubey Asit Ranjan ghosh Centre for Infectious Disease and Control Microbial Molecular Biology LaboratorySchool of Bio Science and Technology VIT UniversityVellore 632014India

Objective: To examine the survivability and stability of probiotic strains in presence and absence of pharmaceutical excipients for a long period of time at(4 ± 1)℃.Methods: The survival rates of probiotic strains, Pediococcus pentosaceus Gs4(MTCC12683)(NCBI HM044322), Gs17(NCBI KJ608061) and Lactobacillus gasseri(ATCC 19992), were evaluated. Probiotic strains were lyophilized individually and in combination of excipients(sorbitol, ascorbic acid, fructose and skim milk). The preparation was monitored for 120 d storing at(4 ± 1)℃. During storage, all the preparations were evaluated for viability and stability of probiotic properties like lactic acid production, antimicrobial effect, water activity, and adherence to epithelial ***: sorbitol, ascorbic acid and skim milk favoured the viability of freeze-dried cells and sustained probiotic properties during storage. Without excipients(control group),strains showed percentage of survivability not more than 70% while strains with excipients survived for 73%–93% for a long period of ***: Commonly used excipients can be considered as a vehicle for delivering active principle in probiotic formulation and for sustaining the viability and stability of probiotic strains for a period of 120 d.

关键词： Viability Probiotics Pediococcus pentosaceus Gs4 P.pentosaceus Gs17 Lactobacillus gasseri Formulation

Effect of Rare Earth and Transition Metal Elements on the Glass Forming Ability of Mechanical Alloyed Al–TM–RE Based Amorphous Alloys

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Journal of Materials science & Technology 2015年第11期31卷 1118-1124页

作者： ram s.Maurya Tapas Laha Department of Metallurgical & Materials Engineering Indian Institute of Technology Kharagpur

The present work aims to compare the amorphous phase forming ability of ternary and quaternary Al based alloys （Al86Ni8Y6, Al86GNi6Y6Co2, Al86NigLa6 and Al86Ni8Y45La15） synthesized via mechanical alloying by varying the composition, i.e. fully or partially replacing rare earth （RE） and transition metal （TM） elements based on similar atomic radii and coordination number. X-ray diffraction and high resolution transmission electron microscopy study revealed that the amorphization process occurred through formation of various intermetallic phases and nanocrystalline FCC Al. Fully amorphous phase was obtained for the alloys not containing lanthanum, whereas the other alloys containing La showed partial amorphization with reappearance of intermetallic phases attributed to mechanical crystallization. Differential scanning calorimetry study confirmed better thermal stability with wider transformation temperature for the alloys without La.

关键词： Al-TM-RE amorphous alloy Mechanical alloying Glass forming ability Microstructural transformation Intermetallics Glass transition temperature

A Generalized Array Factor for Time-Modulated Hexagonal Based Antenna Array Geometry With Novel Trapezoidal switching

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IEEE/CAA Journal of Automatica sinica 2024年第9期11卷 1967-1972页

作者： Gopi ram Department of Electronics and Communication Engineering National Institute of TechnologyWarangal 506004India

The concept of the time-modulated array has been emerging as an alternative to the complex phase shifters,which lowers the cost of the array feeding network due to the utilization of radio frequency(RF)*** various forms of hexagonal antenna array geometries can be used for applications like surveillance tracking in phased array radar and wireless communication *** work proposes the generalized array factor(AF)for the hexagonal antenna array geometry based on time *** time modulation in generalized hexagonal geometry can maintain the fixed static amplitude excitation,giving more flexibility over ***,a novel trapezoidal switching function is also proposed and applied to the generalized array factor to enable future researchers to use this array factor in the field of advancement to observe how switching schemes like trapezoidal and rectangular affect the array pattern's side lobe level(sLL).The generalized equation can be utilized for the analysis and synthesis of radiation characteristics of the time-modulated hexagonal array(TMHA),time-modulated concentric hexagonal array(TMCHA),time-modulated hexagonal cylindrical array(TMHCA),and time-modulated hexagonal concentric cylindrical array(TMHCCA).The numerical result illustrates the generation of AF of time-modulated hexagonal structures and also shows that the trapezoidal switching sequence outperforms the rectangular switch using the cat swarm optimization(CsO)approach.

关键词： Hexagonal array geometry radiation pattern time-modulation trapezoidal pulse

stochastic Models to Mitigate sparse sensor Attacks in Continuous-Time Non-Linear Cyber-Physical systems

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Computers, Materials & Continua 2023年第9期76卷 3189-3218页

作者： Borja Bordel sánchez ramón Alcarria Tomás Robles Information Technologies Department Universidad Politécnica de MadridMadrid28031Spain Geospatial Information Department Universidad Politécnica de MadridMadrid28031Spain

Cyber-Physical systems are very vulnerable to sparse sensor *** current protection mechanisms employ linear and deterministic models which cannot detect attacks ***,in this paper,we propose a new non-linear generalized model to describe Cyber-Physical *** model includes unknown multivariable discrete and continuous-time functions and different multiplicative noises to represent the evolution of physical processes and randomeffects in the physical and ***,the digitalization stage in hardware devices is represented *** and most critical sparse sensor attacks are described through a stochastic *** reconstruction and protectionmechanisms are based on aweighted *** probability in data samples is estimated through different indicators commonly employed in non-linear dynamics(such as the Fourier transform,first-return maps,or the probability density function).A decision algorithm calculates the final reconstructed value considering the previous error *** experimental validation based on simulation tools and real deployments is also carried ***,the new technology performance and scalability are *** prove that the proposed solution protects Cyber-Physical systems against up to 92%of attacks and perturbations,with a computational delay below 2.5 *** proposed model shows a linear complexity,as recursive or iterative structures are not employed,just algebraic and probabilistic *** conclusion,the new model and reconstructionmechanism can protect successfully Cyber-Physical systems against sparse sensor attacks,even in dense or pervasive deployments and scenarios.

关键词： Cyber-physical systems sparse sensor attack non-linear models stochastic models security

A Probabilistic Trust Model and Control Algorithm to Protect 6G Networks against Malicious Data Injection Attacks in Edge Computing Environments

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Computer Modeling in Engineering & sciences 2024年第10期141卷 631-654页

作者： Borja Bordel sánchez ramón Alcarria Tomás Robles Department of Computer systems Universidad Politécnica de MadridMadrid28031Spain Department of Geospatial Engineering Universidad Politécnica de MadridMadrid28031Spain

Future 6G communications are envisioned to enable a large catalogue of pioneering *** will range from networked Cyber-Physical systems to edge computing devices,establishing real-time feedback control loops critical for managing Industry 5.0 deployments,digital agriculture systems,and essential *** provision of extensive machine-type communications through 6G will render many of these innovative systems autonomous and *** full automation will enhance industrial efficiency significantly,it concurrently introduces new cyber risks and *** particular,unattended systems are highly susceptible to trust issues:malicious nodes and false information can be easily introduced into control ***,Denialof-service attacks can be executed by inundating the network with valueless *** anomaly detection schemes require the entire transformation of the control software to integrate new steps and can only mitigate anomalies that conform to predefined mathematical *** based on an exhaustive data collection to detect anomalies are precise but extremely *** models,with their limited understanding of mobile networks,can achieve precision rates no higher than 75%.Therefore,more general and transversal protection mechanisms are needed to detect malicious behaviors *** paper introduces a probabilistic trust model and control algorithm designed to address this *** model determines the probability of any node to be *** channels are pruned for those nodes whose probability is below a given *** trust control algorithmcomprises three primary phases,which feed themodel with three different probabilities,which are weighted and ***,anomalous nodes are identified using Gaussian mixture models and clustering ***,traffic patterns are studied using digital Bessel functions and the functional scalar ***,the in

关键词： 6G networks noise injection attacks Gaussian mixture model Bessel function traffic filter Volterra filter

High Temperature Oxidation of a Work Roll Grade High-Chromium White Cast Iron

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Journal of Iron and steel Research International 2013年第10期20卷 122-129页

作者： J H ramírez-ramírez R Colás N F Garza-Montes-de-Oca Faculty of Mechanical and Electrical Engineering Autonomous University of Nuevo Leon

High-chromium white cast iron is a common material for the manufacture of the work rolls used in the fin- ishing stands in hot strip mills. The high temperature oxidation behaviour of as-cast and heat-treated high-chromium white cast iron was studied by gravimetric means at 650 ℃ in atmospheres that included dry air and a mixture of dry air and water vapour. For both environmental and material conditions, the oxidation rate of the alloys was represen ted by parabolic trends and the oxidation phenomenon was more obvious when the samples were oxidised in water vapour. Water vapour also influenced the chemical composition of the oxides formed in the alloy and under this condi tion, the oxide scale formed on the alloy contained the oxides FeCr2O4 , （Fe,Cr）3O4 and （Fe,Cr）2 O3. In contrast, the alloys exposed to dry air conditions only experienced the formation of FeCr2O4 and （Fe,Cr）2O3. It was found that the presence of water vapour and the chromium content of the alloys increased the oxidation rate by a mechanism that involved chromium depletion of the oxide as a result of hydroxide formation. The differences observed in the oxi- dation behaviour of the alloy are discussed in terms of the composition of the oxidant atmosphere and the metallurgi cal condition of the specimens.

关键词： white cast iron oxidation water vapour work roll

Effects of Vortex Generator on Cylindrical Protrusion Aerodynamics

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Journal of Thermal science 2016年第1期25卷 7-12页

作者： Vignesh ram P.s. Toshiaki setoguchi Heuy Dong Kim school of Mechanical Engineering Andong National University Department of Mechanical Engineering Saga University

Experimental and numerical studies were carried out to evaluate the effect of vortex generator on a small cylindrical protrusion at Mach number 2.0. The experiments were performed using the supersonic blow down wind tunnel on different heights of cylindrical protrusion with vortex generator placed ahead of them. The upstream and downstream flow around the cylindrical protrusion is influenced by vortex generator as is observed using both visualization and pressure measurement techniques. Numerical studies using three dimensional steady implicit formulations with standard k-ω turbulence model was performed. Results obtained through the present computation are compared with the experimental results at Mach 2.0. Good agreements between computation and experimental results have been achieved. The results indicate that the aerodynamic drag acting on cylindrical protrusion can be reduced by adopting vortex generator.

关键词： Cylindrical protrusion Vortex generator shock wave boundary layer interaction Drag control

Effects of mechanical vibration on the physical,metallurgical and mechanical properties of cast A308(LM21)aluminum alloy

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International Journal of Minerals,Metallurgy and Materials 2022年第6期29卷 1206-1215页

作者： siddharth Yadav s.P.Tewari J.K.singh s.C.ram Department of Mechanical Engineering Indian Institute of Technology(BHU)Varanasi 221005India Department of Metallurgical Engineering Indian Institute of Technology(BHU)Varanasi 221005India

This study investigated the microstructure,physical,and mechanical properties of die-cast A308 alloy subjected to mechanical vibration during *** frequencies(0,20,30,40,and 50 Hz)at constant amplitude(31μm)were employed using a power amplifier as the power input device.X-ray diffraction,optical microscopy,and scanning electron microscopy were used to examine the morphological changes in the cast samples under stationary and vibratory *** features of the castings were evaluated using Image J *** average values of metallurgical features,including primaryα-Al grain size,dendrite arm spacing,average area of eutectic silicon,aspect ratio,and percentage porosity,reduced by 34%,59%,56%,22%,and 62%,respectively,at 30 Hz frequency compared with stationary *** tests of the cast samples showed that the yield strength(Ys),ultimate tensile strength(UTs),percentage elongation(%EL),and microhardness(HV)increased by 8%,13%,17%,and 16%,respectively,at 30 Hz frequency compared with stationary *** fractured surface of the tensile specimens exhibited mixed-mode fracture behavior because of brittle facets,cleavage facets,ductile tearing,and dimple *** presence of small dimples showed that plastic deformation occurred before fracture.

关键词： mechanical vibration microstructures microhardness tensile strength fractography