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Particuology 2024年第7期90卷 189-198页

作者： Bina Gidwani Vishal Jain Veenu Joshi ravindra Kumar pandey Shiv Shankar Shukla Amber Vyas Columbia Institute of Pharmacy Raipur(C.G.)India University Institute of Pharmacy Pt Ravishankar Shukla UniversityRaipur(C.G.)India Center for Basic Science and Research Pt Ravishankar Shukla UniversityRaipur(C.G.)India

Simvastatin, a BCS class II drug, is associated with poor aqueous solubility, first-pass metabolism and short half-life. In the present work, nanoparticles were prepared and evaluated. Optimization of formulation and process parameters was done through the use of independent and dependent variables. Preliminary studies were done to determine suitable range of the concentration of Eudragit polymer (10%–30%) and the ratio of drug to polymer (1:1 to 1:5) for the formation of nanoparticles by emulsification and a solvent evaporation technique. Results revealed that the mean size of nanoparticles was affected by stirring speed from 5000 RPM, 8000 RPM, and 12000 RPM. The results of increase in association efficiency and percent yield with increase in amount of drug from 100 mg, 150 mg, and 200 mg in selected range were observed. In-vitro release studies showed that two formulations possess highest initial burst and slow sustained drug release. There was 2.93-fold decrease in total cholesterol and 3.27-fold increases in triglyceride level during in-vivo study.

关键词： Simvastatin Eudragit RS 100 Nanoparticles Hyperlipidemia

A Novel Multi-objective Protection Coordination Scheme for a Microgrid with Optimal Deployment of Dual-setting ROCOV Based Relays

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Protection and Control of Modern Power Systems 2024年第4期9卷 23-38页

作者： Praveen Kumar Gupta Priyanshul Niranjan Niraj Kumar Choudhary Nitin Singh ravindra Kumar Singh the Department of Electrical Engineering Motilal Nehru National Institute of Technology AllahabadPrayagraj 211004India

Relay coordination is crucial in electrical power systems to protect against malfunctions and damage caused by unexpected events like short *** address the challenge associated with the reverse direction of fault current,dual-setting(DS)directional over-current relays have evolved but failed to provide proper coordination during changes of load,generation,and *** the meantime,with the increasing number of DS relays,the total relay operating time tends to ***,this paper proposes a protection scheme based on the optimal deployment of conventional and dual-setting rate of change of voltage(DS-ROCOV)relays in distribution *** holds true for varying network topologies and is unaffected by variations in load and *** objective of the proposed scheme is to ensure reliable and efficient protection against faults in distribution systems by minimizing the overall operating time with the optimal number of DS-ROCOV *** proposed protection scheme’s performance is evaluated for different coordination time interval values as well as in different microgrid *** paper outlines the design and implementation of the proposed protection scheme which is validated on the modified IEEE 14-bus system using simulations in Matlab/Simulink.

关键词： Coordination time interval DS-ROCOV relay multi-objective optimization optimal-deployment protection coordination

SARS-CoV-2 and innate immunity:the good,the bad,and the"goldilocks"

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Cellular & Molecular Immunology 2024年第2期21卷 171-183页

作者： Benjamin L.Sievers Mark T.K.Cheng Kata Csiba Bo Meng ravindra K.Gupta Department of Medicine University of CambridgeCambridgeUK Cambridge Institute of Therapeutic Immunology&Infectious Disease(CITID) Department of MedicineUniversity of CambridgeCambridgeUk

An ancient conflict between hosts and pathogens has driven the innate and adaptive arms of *** about this interplay can not only help us identify biological mechanisms but also reveal pathogen vulnerabilities that can be leveraged *** humoral response to SARS-CoV-2 infection has been the focus of intense research,and the role of the innate immune system has received significantly less ***,we review current knowledge of the innate immune response to SARS-CoV-2 infection and the various means SARS-CoV-2 employs to evade innate defense *** also consider the role of innate immunity in SARS-CoV-2 vaccines and in the phenomenon of long COVID.

关键词： SARS-CoV-2 Innate immune response Interferon Cytokines Inflammation Antiviral targets

Plasma cathepsin L:A prognostic marker for pancreatic cancer

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World Journal of Gastroenterology 2014年第46期20卷 17532-17540页

作者： Nidhi Singh Prasenjit Das Surabhi Gupta Vikas Sachdev Siddhartha Srivasatava Siddhartha Datta Gupta ravindra mohan pandey Peush Sahni Shyam S Chauhan Anoop Saraya Department of Gastroenterology and Human Nutrition All India Institute of Medical SciencesNew Delhi 110029India Deparment of Pathology All India Institute of Medical SciencesNew Delhi 110029India Department of Biostatistics All India Institute of Medical SciencesNew Delhi 110029India Department of GI Surgery All India Institute of Medical SciencesNew Delhi 110029India Department of Biochemistry All India Institute of Medical SciencesNew Delhi110029India

AIM:To assess the prognostic significance of cathepsin L,a cysteine protease that degrades the peri-tumoral tissue,in patients with pancreatic ***:Plasma samples from 127 pancreatic cancer patients were analyzed for cathepsin L levels by *** of these patients,25 underwent surgeryand their paraffin-embedded tissue was analyzed for cathepsin L expression by *** of patients and clinicopathological parameters was correlated with cathepsin L expression in plasma and tissue using appropriate statistical ***:The mean(±SD)cathepsin L in plasma samples of pancreatic cancer patients was 5.98±2.5ng/m L that was significantly higher compared to the levels in healthy controls(3.83±0.45)or chronic pancreatitis patients(3.97±1.06).Using ROC curve,a cut-off level of 5.0 ng/m L was decided for survival *** plasma levels of cathepsin L were found to be associated with poor prognosis(P=0.01)in multivariate *** plasma levels of the protease decreased after *** no significant correlation was seen between plasma and tissue expression of this protease,a trend did emerge that high cathepsin L expression in tissue correlated with its high levels in ***:Cathepsin L levels in plasma of pancreatic cancer patients may be used as a potential prognostic marker for the disease.

关键词： Cathepsin L Pancreatic cancer Overall median survi

Polyvinyl Acetate and Vinyl Acetate-Ethylene Hybrid Adhesive: Synthesis, Characterization, and Properties

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Open Journal of Polymer Chemistry 2024年第1期14卷 1-18页

作者： ravindra V. Gadhave Department of Polymer and Surface Engineering Institute of Chemical Technology Mumbai India

The goal is to develop a hybrid IPN network of polyvinyl acetate (PVAc) and ethylene-vinyl acetate (VAE). In this research work, the vinyl acetate (VAc)/ VAE hybrid emulsion and polyvinyl acetate emulsion (PVAc) were effectively synthesized. Emulsions with various characteristics have been developed by adjusting the weight ratios between the vinyl acetate monomer and the VAE component. The impacts on the mechanical, thermal, and physical properties of the films were investigated using tests for pencil hardness, tensile shear strength, pH, contact angle measurement, differential scanning calorimetry (DSC), and viscosity. When 5.0 weight percent VAE was added, the tensile shear strength in dry conditions decreased by 18.75% after a 24-hour bonding period, the heat resistance decreased by 26.29% (as per WATT 91) and the tensile shear strength decreased by approximately 36.52% in wet conditions (per EN 204). The pristine sample’s results were also confirmed by the contact angle test. The interpenetrating network (IPN) formation in hybrid PVAc emulsion as primary bonds does not directly attach to PVAc and VAE chains. The addition of VAE reduced the mechanical properties (at dry conditions) and heat resistance as per WATT 91. Contact angle analysis demonstrated that PVAc adhesives containing VAE had increased water resistance when compared to conventional PVA stabilised PVAc homopolymer-based adhesives. When compared to virgin PVAc Homo, the water resistance of the PVAc emulsion polymerization was enhanced by the addition of VAE.

关键词： Ethylene-Vinyl Acetate Dispersion Polyvinyl Acetate Hybrid Wood Adhesive

Location Prediction from Social Media Contents using Location Aware Attention LSTM Network

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Journal of Harbin Institute of Technology(New series) 2024年

作者： Madhur Arora Sanjay Agrawal ravindra Patel Department of Computer Application National Institute of Technical Teachers Training and Research Department of Computer Application University Institute of Technology Rajiv Gandhi Proudyogiki Vishwavidyalaya

Location prediction in social media， a growing research field， employs machine learning to identify users’ locations from their online activities. This technology， useful in targeted advertising and urban planning， relies on natural language processing to analyze social media content and understand the temporal dynamics and structures of social networks. A key application is predicting a Twitter user’s location from their tweets， which can be challenging due to the short and unstructured nature of tweet text. To address this challenge， the research introduces a novel machine learning model called the location-aware attention LSTM (LAA-LSTM). This hybrid model combines a Long Short-Term Memory (LSTM) network with an attention mechanism. The LSTM is trained on a dataset of tweets， and the attention network focuses on extracting features related to latitude and longitude， which are crucial for pinpointing the location of a user’s tweet. The result analysis shows approx. 10% improvement in accuracy over other existing machine learning approaches.

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Indoor Formaldehyde Removal Techniques through Paints: Review

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Green and Sustainable Chemistry 2024年第1期14卷 1-15页

作者： Prajyot Dhawale ravindra V. Gadhave Department of Polymer and Surface Engineering Institute of Chemical Technology Mumbai India

Due to its ability to cause illnesses and discomfort even at low concentrations, formaldehyde pollution of indoor air poses a significant risk to human health. Sources of formaldehyde in indoor environments include textiles, paints, wallpapers, glues, adhesives, varnishes, and lacquers;furniture and wooden products like particleboard, plywood, and medium-density fiberboard that contain formaldehyde-based resins;shoe products;cosmetics;electronic devices;and other consumer goods like paper products and insecticides. According to the World Health Organisation, indoor formaldehyde concentrations shouldn’t exceed 0.1 mg/m3. The methods include membrane separation, plasma, photocatalytic decomposition, physisorption, chemisorption, biological and botanical filtration, and catalytic oxidation. Materials based on metal oxides and supported noble metals work as oxidation catalysts. Consequently, a paint that passively eliminates aldehydes from buildings can be developed by adding absorbents and formaldehyde scavengers to the latex composition. It will be crucial to develop techniques for the careful detection and removal of formaldehyde in the future. Additionally, microbial decomposition is less expensive and produces fewer pollutants. The main goal of future research will be to develop a biological air quality control system that will boost the effectiveness of formaldehyde elimination. The various methods of removing formaldehyde through paints have been reviewed here, including the use of mixed metal oxides, formaldehyde-absorbing emulsions, nano titanium dioxide, catalytic oxidation, and aromatic formaldehyde abating materials that can improve indoor air quality.

关键词： Formaldehyde Absorption Paints Catalytic Oxidation Nanofillers

Reinforcing Effect of Graphene in Epoxy Adhesives: Review

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Open Journal of Composite Materials 2024年第1期14卷 60-70页

作者： Fatehbahadur Purushottam Lodh ravindra Vilas Indubai Gadhave Asian Paints Ltd. Research & Technology Centre Navi Mumbai India

Due to its great strength, hardness, and chemical resistance, epoxy adhesives are becoming more and more used. They continue to have drawbacks, nevertheless, such as poor thermal stability, and poor electrical conductivity. Two-dimensional graphene is a wonderful substance with exceptional qualities including high strength, high electrical conductivity, and large surface area. Because of these characteristics, graphene has been thoroughly researched for its prospective uses in a variety of industries, including electronics, energy storage, and biomedical engineering. The use of graphene as an additive in epoxy adhesives to enhance the characteristics of such materials is one of its promising uses. This paper reviewed the latest findings about graphene’s effects on epoxy adhesives. The various methods to produce graphene-epoxy composites and their improvements are discussed. This research additionally discusses the challenges associated with the production and processing of graphene-epoxy composites, as well as the mechanisms behind the improvements in mechanical, electrical, and thermal characteristics. The final section of this review discusses the challenges and prospective uses of graphene in epoxy adhesives in the future.

关键词： Graphene Epoxy Adhesives Composite Mechanical Properties

Polyurethane Hybrid-Based Wood Adhesive: Review

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Open Journal of Polymer Chemistry 2024年第1期14卷 41-62页

作者： Rahul Khandagale Sainath Gadhave ravindra V. Gadhave Super Bond Adhesives Private Limited Thane India

Based on commercially available polyvinyl alcohol (PVA) stabilised polyvinyl acetate (PVAc), emulsion adhesives are neither heat nor moisture-resistant and show weak strength at high relative humidity and high temperatures. Pre- or post-crosslinking is another method used to manufacture a conventional vinyl-based homopolymers or copolymers system with improved water resistance. Vinyl neodecanoate (VeoVa), N-methylolacrylamide (NMA), Methacrylamide, methacrylic acid (MAA), and other self-crosslinking comonomers are typically inserted to produce highly water-resistant vinyl based homopolymers or copolymers. Additionally, organic crosslinkers like glyoxal, glutaraldehyde, citric acid, tartaric acid, and the like, as well as inorganic crosslinkers like acidic metal salts like aluminium chloride, aluminium nitrate, boric acid, and the like, can be used to prepare the highly water-resistant vinyl based homopolymers or copolymers. It is also possible to combine the self-crosslinking comonomers with the organic crosslinkers. Recently, a different hybrid chemistry has been developed that improves lap shear strength, has outstanding water resistance, good durability, and doesn’t require any additional crosslinker agents. Two distinct polymers were combined to develop hybrid polymers. They usually involve mixing an organic polymer with a polymer. There are many capping agents that are used for polyurethanes to produce acrylics that are capped with polyurethane and used as an oligomer in PVAc wood glue. Here, in this paper, we reviewed the different hybrid chemistry based on polyurethane chemistry for wood bonding applications.

关键词： Vinyl Acetate Hybrid Polyurethane Wood Adhesive

Petrogenesis of massif-type anorthosite complex, Gruber, Central Dronning Maud Land, East Antarctica: Implications for magma source and evolution

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Chinese Journal Of Geochemistry 2009年第4期28卷 340-350页

作者： Anju pandey Amit Dharwadkar Rasik ravindra Andy Milton National Oceanography Centre European WaySouthampton SO14 3ZH United Kingdom Geological Survey of India FaridabadNH31 Haryana India National Centre for Antarctic & Ocean Research Goa-403804 India

The origin of anorthosite and associated igneous gabbronorite and ferrodiorite was investigated through detailed study of a typical massif-type anorthosite complex from Gruber, Central Dronning Maud Land, East Antarc- tica. Field observations showed that the Gruber Complex is made up of gabbronorite-anorthosite pluton which was intruded by ferrodiorite dykes. Systematic samples collected from the Gruber Complex revealed significant geo- chemical variations within the region. Four rock types have been identified, based on modal proportions of mineral phases and their geochemistry data. Clinopyroxene-gabbronorite and plagioclase-gabbronorite are the two types of gabbronorite with the dominance of clinopyroxene and plagioclase, respectively. Anorthosite is represented by rocks having predominance of plagioclase with minor clinopyroxene. Ferrodiorite is characterized by modal abundance of orthopyroxene and Fe-Ti oxide. Major and trace element systematics showed that all the four rock types are co-magmatic and are related through fractional crystallization. Based on this study, it is reported that clinopyroxene was the first phase to crystallize followed by plagioclase and then Fe-Ti oxides. Furthermore, trace element composition of the parental melt was calculated using LA-ICPMS analysis of the most primitive, pure clinopyroxene found in the clinopyroxene gabbronorite. Our analyses suggested that the parental melt was similar to that of continental arc basalt and showed signatures of subduction-related metasomatism. Based on mineral chemical and geochemical data, it is interpreted that the parent melt went through changing sequence of crystallization which led to the forma- tion of massive anorthosite.

关键词：东南极洲斜长岩岩浆源块型成因中央演变