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Advances in Bioscience and Biotechnology 2013年第11期4卷 24-29页

作者： Selva Rivas-Arancibia Luis Fernando Hernández-Zimbrón Erika Rodríguez-Martínez Gabino Borgonio-Pérez varsha velumani Josefina Durán-Bedolla Centro de Investigación Sobre Enfermedades Infecciosas Instituto Nacional de Salud Pública Cuernavaca México Departamento de Fisiología Facultad de Medicina Universidad Nacional Autónoma de México México D. F. México

Chronic exposure to low doses of ozone similar to a day of high pollution in Mexico City causes a state of oxidative stress. This produces a progressive neurodegeneration in hippocampus of rats exposed to the gas. The aim of this study was to analyze the effect of chronic exposure on the changes in the blood-brain barrier in rats exposed to low doses of ozone. Method: each group received one of the following treatments, control group received air without ozone, and groups 2, 3, 4, 5, and 6 received ozone doses of 0.25 ppm for 4 h daily during 7, 15, 30, 60 and 90 days respectively. Each group was processed to inmunohistochemical technique against of the following antibody: blood-brain barrier, guanylyl cyclase, Iba-1, GFAP, NFκ-B, TNF-α. The results show that there is a correlation between the time exposure of ozone and the progressive damage, on the blood-brain barrier rupture, finally causing edema of endothelial cell, increase in guanylyl cyclase type 1, thickening of the processes and astrocytes foot, and an increase in the expression of factors NFκ-B and TNF-α at 30 and 60 days of exposure to this gas. All the above indicates that the chronic state of oxidative stress causes a neurodegeneration process, accompanied by disruption of the blood-brain barrier likely to occur in the Alzheimer’s disease.

关键词： Ozone Oxidative Stress Blood-Brain Barrier Neurodegenerative Diseases

Synthesis of malachite@clay nanocomposite for rapid scavenging of cationic and anionic dyes from synthetic wastewater

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Journal of Environmental Sciences 2017年第1期29卷 97-110页

作者： varsha Srivastava Mika Sillanpää Laboratory of Green Chemistry School of Engineering ScienceLappeenranta University of TechnologySammonkatu 12FI 50130MikkeliFinland

Synthesis of malachite@clay nanocomposite was successfully carried out for the removal of cationic（Methylene Blue,MB） and anionic dyes（Congo Red,CR） from synthetic *** was characterized by TEM,SEM,FT-IR,EDS analysis and zeta *** analysis indicated that the particle diameter of nanocomposite was in the range of 14 to23 *** important parameters *** time,concentration of dyes,nanocomposite dosage,temperature and solution pH were optimized to achieve maximum adsorption *** the case of MB,removal decreased from 99.82%to 93.67%while for CR,removal decreased from 88.55%to 75.69%on increasing dye concentration from 100 to 450 mg/*** study confirmed the higher removal of CR in acidic range while MB removal was higher in alkaline *** study revealed the applicability of pseudo-second-order model for the adsorption of both *** values of AG0 for both systems suggested the feasibility of dye removal and support for spontaneous adsorption of CR and MB on *** showed 277.77 and 238.09 mg/g Langmuir adsorption capacity for MB and CR *** of dyes from the dye loaded nanocomposite was easily carried out with *** results indicate that the prepared malachite@clay nanocomposite is an efficient adsorbent with high adsorption capacity for the aforementioned dyes.

关键词： Adsorption Bentonite Dyes Kinetic study Methylene blue Congo red

TLERAD: Transfer Learning for Enhanced Ransomware Attack Detection

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Computers, Materials & Continua 2024年第11期81卷 2791-2818页

作者： Isha Sood varsha Sharm a School of Information Technology Rajiv Gandhi Proudyogiki VishwavidyalayaBhopal462033India

Ransomware has emerged as a critical cybersecurity threat,characterized by its ability to encrypt user data or lock devices,demanding ransom for their *** ransomware detection methods face limitations due to their assumption of similar data distributions between training and testing phases,rendering them less effective against evolving ransomware *** paper introduces TLERAD(Transfer Learning for Enhanced Ransomware Attack Detection),a novel approach that leverages unsupervised transfer learning and co-clustering techniques to bridge the gap between source and target domains,enabling robust detection of both known and unknown ransomware *** proposed method achieves high detection accuracy,with an AUC of 0.98 for known ransomware and 0.93 for unknown ransomware,significantly outperforming baseline *** experiments demonstrate TLERAD’s effectiveness in real-world scenarios,highlighting its adapt-ability to the rapidly evolving ransomware *** paper also discusses future directions for enhancing TLERAD,including real-time adaptation,integration with lightweight and post-quantum cryptography,and the incorporation of explainable AI techniques.

关键词： Ransomware detection transfer learning unsupervised learning co-clustering cybersecurity machine learning lightweight cryptography post-quantum cryptography explainable AI TLERAD

Sulfide oxidation in fluidized bed bioreactor using nylon support material

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Journal of Environmental Sciences 2012年第3期24卷 512-519页

作者： varsha Midha M K Jha Apurba Dey Department of Chemical Engineering National Institute of TechnologyJalandhar 144011India Department of Biotechnology National Institute of Technology DurgapurIndia

A continuous fluidized bed bioreactor （FBBR） with nylon support particles was used to treat synthetic sulfide wastewater at different hydraulic retention time of 25, 50 and 75 min and upflow velocity of 14, 17 and 20 m/hr. The effects of upflow velocity, hydraulic retention time and reactor operation time on sulfide oxidation rate were studied using statistical model. Mixed culture obtained from the activated sludge, taken from tannery effluent treatment plant, was used as a source for microorganisms. The diameter and density of the nylon particles were 2-3 mm and 1140 kg/m3, respectively. Experiments were carried out in the reactor at a temperature of （30 ± 2）°C, at a fixed bed height of 16 cm after the formation of biofilm on the surface of support particles. Biofilm thickness reached （42 ± 3） μm after 15 days from reactor start-up. The sulfide oxidation, sulfate and sulfur formation is examined at all hydraulic retention times and upflow velocities. The results indicated that almost 90%-92% sulfide oxidation was achieved at all hydraulic retention times. Statistical model could explain 94% of the variability and analysis of variance showed that upflow velocity and hydraulic retention time slightly affected the sulfide oxidation rate. The highest sulfide oxidation of 92% with 70% sulfur was obtained at hydraulic retention time of 75 min and upflow velocity of 14 m/hr.

关键词： biofilm fluidized bed bioreactor mixed culture sulfide oxidation

Single-stage Five-level Common Ground Transformerless Inverter with Extendable Structure for Centralized Photovoltaics

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CSEE Journal of Power and Energy Systems 2023年第1期9卷 37-49页

作者： Vishal Anand varsha Singh Jagabar Sathik Dhafer Almakhles Department of Electrical Engineering National Institute of Technology RaipurIndia Renewable Energy Lab Prince Sultan UniversityRiyadh11586Saudi Arabia Department of Electrical and Electronics Engineering SRM Institute of Science and TechnologyKattankulathur Campus603203-Tamil NaduIndia

The paper presents a five-level common ground type(5L-CGT),transformer-less inverter topology with double voltage *** proposed inverter uses eight switches and two capacitors,charged at input voltage *** inverter in its basic form acts as a string inverter for low-power PV ***,it can be extended to work as a scalable multi-level inverter with higher power handling capability to act as a centralized *** working of the inverter with the sizing of the components is presented with mathematical *** efficiency of the proposed PV inverter is found using thermal losses associated with switches using PLECS software.A prototype of 1 kW has been designed,and experimentation has been carried *** loads with a lagging power factor up to 0.6 have been tested with the inverter to establish the usability of the proposed inverter in a worst-case emulated homeuse *** total harmonic distortion(THD)at the output has been recorded using a power quality analyzer with voltage and current THD values of 4.5%and 2.5%,respectively,which lies within the limits of IEEE 519 *** highest power conversion efficiency of the inverter has been recorded to be 96.20%.

关键词： Active and reactive power boost inverter common mode voltage(CMV)grid-tied inverters inrush current leakage current photovoltaics

Sulfonic acid-functionalized mesoporous silica catalyst with different morphology for biodiesel production

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Frontiers of Chemical Science and Engineering 2022年第8期16卷 1198-1210页

作者： Vinayak Hegde Parimal Pandit Pranita Rananaware varsha PBrahmkhatri Centre for Nano and Material Sciences Jain UniversityJain Global CampusBengaluru 562112India

Sulfonic acid functionalized mesoporous silica based solid acid catalysts with different morphology were designed and *** synthesized materials were characterized by various physicochemical and spectroscopic techniques like scanning electron microscopeenergy dispersive X-ray spectroscopy,Fourier transform infrared spectroscopy,Brunauer–Emmett–Teller surface area,thermogravimetric analysis and n-butylamine *** shape of catalysts particles plays an important role in its *** sulfonic acid functionalized mesoporous silica catalysts of spherical shape and the cube shape were assessed for catalytic activity in biodiesel *** catalytic biodiesel production reaction over the catalysts were studied by esterification of free fatty acid,oleic acid with *** effect of various reaction parameters such as catalyst concentration,acid/alcohol molar ratio,catalyst amount,reaction temperature and reaction time on catalytic activity were investigated to optimize the conditions for maximum *** was sulfonated cubic shape mesoporous silica which exhibited better activity as compared to the spherical shape silica ***,the catalyst was regenerated and reused up to three cycles without any significant loss in *** present catalysts exhibit superior performance in biodiesel production and it can be used for the several biodiesel feedstock’s that are rich in free fatty acids.

关键词： solid acid catalyst mesoporous silica sulfonic acid biodiesel esterification oleic acid

Solving systems of multi-term fractional PDEs:Invariant subspace approach

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International Journal of Modeling, Simulation, and Scientific Computing 2019年第1期10卷 130-154页

作者： Sangita Choudhary varsha Daftardar-Gejji Department of Mathematics Savitribai Phule Pune University Pune 411007India

In the present paper,invariant subspace method has been extended for solving systems of multi-term fractional partial differential equations(FPDEs)involving both time and space fractional ***,the method has also been employed for solving multi-term fractional PDEs in(1+n)dimensions.A diverse set of examples is solved to illustrate the method.

关键词： Time and space fractional partial differential equations systems of fractional partial differential equations invariant subspace method

Synthesis and application of biocompatible nontoxic nanoparticles for reclamation of Ce^3＋ from synthetic wastewater： Toxicity assessment, kinetic, isotherm and thermodynamic study

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Journal of Rare Earths 2018年第9期36卷 994-1006页

作者： varsha Srivastava Sidra Iftekhar ZhaoWang Indu Babu Mika Sillanpaa Laboratory of Green Chemistry School of Engineering Science Lappeenranta University of Technology Sammonkatu 12 FI-50130 Mikkeli Finland Department of Civil and Environmental Engineering Florida International University Miami EL 33174 USA

The aim of present study is to synthesize forsterite nanoparticles（FRST） for the reclamation of cerium ions（Ce3＋） from synthetic *** aim to synthesize FRST nanoparticles is due to its biocompatible and nontoxic *** formation of nanoparticles with average diameter of 58 nm was confirmed by TEM *** images of bare FRST nanoparticles show a heterogeneous surface with porous *** surface area of FRST nanoparticles is calculated to be 33.69 m2/*** significant uptake of Ce3＋ ions can be obtained for all the selected concentrations（25-150 mg/L） within 2 h of adsorbent—adsorbate *** pH study shows that by increasing pH from acidic to alkaline range,higher removal can be *** study demonstrates the endothermic nature of Ce3＋*** value of sticking probability suggests very high sticking probability of Ce3＋ ion for FRST ***3＋ uptake is favored by higher temperature and with the increase in temperature from298 to 328 K,Langmuir adsorption capacity increases from 36.45 to 42.99 m2/*** of FRST nanoparticles was also investigated for other light and heavy rare earth elements in single solute and multisolute systems,FRST nanoparticles show the significant removal of divalent metallic pollutants as *** assessment of chemical toxicity of treated wastewater was carried out with the bioluminescent photobacterium（Vibrio fischeri） and decreased toxicity was observed in treated water *** outcome of present study suggests that the FRST nanoparticles can be efficiently utilized for the removal of Ce3＋ ions and a wide range of other pollutant species as well.

关键词： Forsterite Rare earth elements Isotherm model Cerium Metallic pollutants

Co-Occurrence Histogram Based Ensemble of Classifiers for Classification of Cervical Cancer Cells

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Journal of Electronic Science and Technology 2022年第3期20卷 270-281页

作者： Rajesh Yakkundimath varsha Jadhav Basavaraj Anami Naveen Malvade the Department of Computer Science and Engineering Karnataka Lingayat Education Institute of TechnologyHubballi580027India Department of Information Science and Engineering Shri Dharmasthala Manjunatheshwara College of Engineering and TechnologyDharwad580008India the Department of Information Science and Engineering Smt.Kamala&Sri.Venkappa M.Agadi College of Engineering and TechnologyLakshmeshwar582116India the Visvesvaraya Technological University Belagavi590018India

To explore the potential of conventional image processing techniques in the classification of cervical cancer cells, in this work, a co-occurrence histogram method was employed for image feature extraction and an ensemble classifier was developed by combining the base classifiers, namely, the artificial neural network(ANN),random forest(RF), and support vector machine(SVM), for image classification. The segmented pap-smear cell image dataset was constructed by the k-means clustering technique and used to evaluate the performance of the ensemble classifier which was formed by the combination of above considered base classifiers. The result was also compared with that achieved by the individual base classifiers as well as that trained with color, texture, and shape features. The maximum average classification accuracy of 93.44% was obtained when the ensemble classifier was applied and trained with co-occurrence histogram features, which indicates that the ensemble classifier trained with co-occurrence histogram features is more suitable and advantageous for the classification of cervical cancer cells.

关键词： Cervical cancer co-occurrence histogram ensemble classification k-means clustering

Activator-assisted electroless deposition of copper nanostructured films

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International Journal of Minerals,Metallurgy and Materials 2014年第2期21卷 196-203页

作者： varsha R. Mehto R. K. Pandey Department of Physics Barkatullah University NIIT University

This paper showed simple and effective synthesis of copper nanoparticles within controlled diameter using direct electroless deposition on glass substrates, following the sensitization and activation steps. Electroless-deposited metals, such as Cu, Co, Ni, and Ag, and their alloys had many advantages in micro- and nanotechnologies. The structural, morphological, and optical properties of copper deposits were characterized using X-ray diffraction （XRD）, atomic force microscopy （AFM）, and UV-Vis spectroscopy. The structural data was further analyzed using the Rietveld refinement program. Structural studies reveal that the deposited copper prefers a （111） orientation. AFM studies suggest the deposited materials form compact, uniform, and nanocrystalline phases with a high tendency to self-organize. The data show that the particle size can be controlled by controlling the activator concentration. The absorption spectra of the as-deposited copper nanoparticles reveal that the plasmonic peak broadens and exhibits a blue shift with decreasing particle size.

关键词： nanostructured materials thin films copper electroless plating deposition