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Molecular docking study, and ADMET analysis for the synthesized novel Zn(II) complexes as potential SARS-CoV-2 inhibitors
A new SARS-CoV-2 virus and its variants including omicron created a pandemic situation and caused more deaths in worldwide prompted many researchers to explore potential drug candidates. In this connection, we explored the first-of-its-kind report on computational studies such as molecular docking, and ADMET properties of Zn(II) complexes. The studies revealed the novel zinc complexes have high binding affinities with the SARS-CoV-2 spike glycoprotein (6vxx) alpha variant (7EKF), beta variant (7ekg), gamma variant (7EKC), delta variant (7V8B), and the omicron variant (7T9J). Molecular docking results of RMSD for SARS-CoV-2 beta variant (7ekg) and gamma variant (7EKC) are within excellent chemical stability in their protein-ligand complex state and should be effective in the biological system. ADME studies provided the better results with no adverse effect of toxicity related AMES along with absence of hepatotoxicity and skin sensitization when compared to Molnupiravir drug and it has a greater hepatotoxicity. This study could open further exploration of these novel zinc complexes for SARS-CoV-2 inhibition. (2024) DergiPark. -
Molecular level investigation on the impact of geometric isomers as fluorinated ligands in SIFSIX MOF for natural gas sweetening
In natural gas (NG), significant amounts of hydrogen sulfide (H2S) and carbon dioxide (CO2) are the most menacing contaminants that cause degradation of the purity of fuel. We considered fluorine-functionalized MOFs and employed cheaper and faster computational simulation techniques to understand the adsorption process. Hence, this includes structural optimization of newly designed fluorine-functionalized MOF with Density Functional Theory (DFT) and further Grand Canonical Monte Carlo (GCMC) simulation at room temperature on those MOFs for understanding in detail the adsorptive separation process on sour gases. However, the main emphasis has been made on the adsorptive separation of H2S gas from sour gas. Eventually, the fluorination of organic ligand in [(SiF6)Ni(1,2-di(pyridin-4-yl)ethyne)2] MOF has resulted in an excellent H2S/CO2 separation performance from NG because of the different geometrical isomers. The cis isomer of 1,2-di(pyridin-4-yl)ethyne as ligand in MOF, i.e., SIFSIX-Ni-dpe-3-cis, shows a high CO2 affinity than H2S; on the contrary, the trans isomer of 1,2-di(pyridin-4-yl)ethyne as ligand in MOF, i.e., SIFSIX-Ni-dpe-3-trans, has H2S selective over CO2 and CH4. So, the resulting affinity variation indicates that structural variation by the stereochemistry of ligands in MOF plays a significant role in NG purification, which is further validated through detailed molecular simulation analysis. 2022 Taylor & Francis Group, LLC. -
Molecular phylogenetics and character evolution in Haplanthodes (Acanthaceae), an endemic genus from peninsular India
Haplanthodes (Acanthaceae) is an Indian endemic genus with four species. It is closely related to Andrographis which is also mainly distributed in India. Haplanthodes differs from Andrographis by the presence of cladodes in the inflorescences, subactinomorphic flowers, stamens included within the corolla tube, pouched stamens and oblate pollen grains. To understand the phylogenetic relationship of Haplanthodes, Andrographis and Haplanthus, which are putatively closely related taxa, we used four plastid markers, matK, rbcL, psbA-trnH and trnGRto construct a molecular phylogeny. Our results established the monophyly of Haplanthodes and revealed a sister relationship to Andrographis and Haplanthus. Further, to understand the historical biogeography of the genus, we inferred the divergence time and performed an ancestral area reconstruction. Our analyses suggest that Haplanthodes evolved during Late Miocene 5.85 Ma (95%HPD: 2.1810.34 Ma) in peninsular India where it might have shared a common ancestor with Andrographis. To understand character evolution, the ancestral states of important morphological characters were inferred and discussed based on the equal rate model. The generic status of Haplanthus was not resolved due to incomplete sampling. 2022 Nordic Society Oikos. Published by John Wiley & Sons Ltd. -
Molecular Simulation Prediction on SO2 Gas Adsorption in Bipyridine Ligand-Based Square-Pillared MOFs
Increasing concentrations of toxic gases caused by the burning of fossil fuels necessitates the development of efficient porous materials for gas capture. Metal-organic frameworks (MOFs) have attracted a lot of attention as potential porous materials due to their effectiveness in adsorption of toxic gases. In particular, square-pillared metal-organic frameworks stand out for their exceptional potential toward gas adsorption, attributed to their remarkable surface area, thermal and chemical stabilities, and tunable properties. In this context, molecular simulations have been executed to observe and analyze the adsorption process of toxic flue gases such as SO2 and CO2 on MOFs. The present work deals with two different stable fluorinated MOFs named [Ni(4,4?-bipyridine)2(AlF5)]n (ALFFIVE-Ni-bipy) and [Ni(4,4?-bipyridine)2(NbOF5)]n, (NBOFFIVE-Ni-bipy) featuring AlF52- and NbOF52- anion pillars, respectively, comprising 4,4?-bipyridine as organic ligand and nickel as the central metal. The significance of utilizing the 4,4?-bipyridine ligands in these fluorinated MOFs enhances the SO2 gas adsorption and selectivity in the framework. Density functional theory has been implemented for geometry optimization, and Grand Canonical Monte Carlo simulations have been performed to forecast the adsorption isotherms. Both ALFFIVE-Ni-bipy (11.4 mmol/g) and NBOFFIVE-Ni-bipy (8.7 mmol/g) showed high SO2 adsorption capacity at 1 bar pressure, but ALFFIVE-Ni-bipy showed very good adsorption than other square-pillared MOFs and also unveiled good selectivity of SO2 gas. The coadsorption of binary SO2/CO2 and ternary SO2/CO2/N2 gas mixtures at ambient conditions indicated that the cost-effective aluminum (Al)-based square-pillared ALFFIVE-Ni-bipy is particularly suitable for acid gas adsorption. 2024 American Chemical Society -
Molecular simulations to investigate the guest-induced flexibility of Pu-UiO-66 MOF
Actinide metal-organic frameworks are highly popular because of their significant coordination benefits. Due to production and characterisation challenges, An-MOFs are a relatively less explored coordination polymer. In this study, we considered the experimentally synthesised Pu-UiO-66 MOF, which was the first reported plutonium MOF. In most MOF studies, the framework has been maintained rigid, however, in this case, we investigate both rigid and flexible frameworks. To gain a better understanding of the framework's flexibility, flexible Grand Canonical Monte Carlo (GCMC) simulations were conducted and the calculated results were compared with that of rigid frameworks. Molecular Dynamics (MD) simulations were carried out to examine the effects of framework flexibility of Pu-UiO-66 MOF, a force field-built Grand Canonical Monte Carlo (GCMC) on adsorption of guest molecules, and to analyse the self-diffusion coefficients of acidic gases such as CO2, SO2, and NO2 in the framework. The adsorption isotherms and radial distribution functions for both rigid and flexible frameworks in the presence of gas molecules were compared and analysed using GCMC simulation. Similarly, molecular dynamics simulations including guest molecules were carried out. Following that, the GCMC and MD results were compared and analysed to determine the flexibility of the system. Diffusion studies were conducted at various temperatures and the coefficient of self-diffusion of each gas was examined. In addition, structural analyses, such as angle analysis, were carried out to explore the local changes, such as tilting, observed in the organic ligand derivative. It was also shown that the UFF force field is suitable for Pu-UiO-66. 2022 -
Molecularly imprinted graphene based biosensor as effective tool for electrochemical sensing of uric acid
Graphene oxide based molecularly imprinted polymer was designed by incorporating vinyltrimethoxysilane into the layers of graphene oxide, which was copolymerized with functional monomers such as Itaconic acid (IA) and methyl methacrylate (MMA) was developed via bulk imprinting technique. The prepared polymer was studied for selective sensing the uric acid (UA) in blood serum. The electrode was constructed by modifying bare glassy carbon electrodes with the prepared molecularly imprinted polymer (MIP) via drop cast method. Electrochemical measurements were made by Cyclic voltammetric (CV) and Differential Pulse Voltammetric (DPV) response of the sensor. The physical and chemical properties of the resultant material will be characterized by FTIR spectroscopy, XRD and FESEM. The constructed sensor showed a regression coefficient (R2) of 0.9302 with limit of detection (LOD) of about 0.565 ??M. The developed sensor is reusable without any compromise in its selectivity. All the results confirm that the constructed biosensor requires no pre-treatment of samples and is suitable for real sample analysis. 2023 The Authors -
Molecularly imprinted PEDOT on carbon fiber paper electrode for the electrochemical determination of 2,4-dichlorophenol
A highly selective electrochemical sensor has been developed for the determination of the pesticide molecule, 2,4-dichlorophenol (2,4-DCP) using molecularly imprinted conducting polymer. 2,4-dichlorophenol imprinted polymer films were prepared by electropolymerising 3,4-ethylenedioxythiophene (EDOT) on surface of carbon fiber paper electrode (CFP) in presence of 2,4-dichlorophenol. Electrochemical over-oxidation was carried out for the controlled release of 2,4-DCP templates and to generate definite imprinting sites. Surface morphology of the imprinted electrode was analysed by Scanning Electron Microscopy-Energy Dispersive X-ray Spectrometry, Fourier Transform Infrared and Raman spectroscopy. In optimized conditions, the voltammetric sensor gave a linear response in the range of 0.21 nM 300 nM. The significantly low detection limit (0.07 nM) demonstrates the ultra-low sensitivity of the method. The imprinted sensor displayed higher affinity and selectivity towards the target 2,4-DCP over similar structural analogical interference than the non-imprinted sensor. MIP sensor was efficaciously employed for the selective determination of 2,4-DCP in real samples of water. 2020 Elsevier B.V. -
Molecularly Imprinted Scaffold Based on poly (3-aminobenzoic acid) for Electrochemical Sensing of Vitamin B6
Inadequate or excess consumption of Vitamin B6 (Vit B6) can have ill effects on the overall well-being of humans, thereby making it necessary to control their content and composition in the food we consume. A simple sensor is fabricated in this work for Vit B6 detection based on employing an electropolymerized molecularly imprinted polymer (MIP) of 3-amino benzoic acid. The poly (3- aminobenzoic acid) (P-(3ABA)) film was electrodeposited by potentiodynamic cycling of potential with and without Vit B6 (template) on carbon fiber paper electrode (CFP). The modified working electrodes were characterized by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). Field emission scanning microscopy, Energy dispersive X-ray spectrometry, Fourier Transform Infrared spectroscopy, Optical profilometry and X-ray photon electron spectroscopy were used for characterization. Nyquist plots revealed least charge transfer resistance at MIP/CFP than other control electrodes due to the molecularly imprinted sites. Under the optimized experimental conditions the developed MIP sensor showed a linear range 0.6 ?M to 700 ?M, with a detection limit of 0.010 ?M. Also a value of the imprinting factor (? = 3.50) indicates very good selectivity of the prepared sensor towards Vit B6 detection over its structurally similar analogues in the analysis of real sample matrices. 2021 The Electrochemical Society ("ECS"). Published on behalf of ECS by IOP Publishing Limited. -
Monetary policy announcement and stock price behaviour: An event study with respect to India
Monetary policy in a developing country plays a significant role in achieving the objectives of macroeconomic policies. The Central Bank formulates and implements the monetary policy in a country which in turn facilitates the increase in growth rate, manages interest rates, and money supply in the economy. The primary objective of this paper is to test the semi-strong form of Efficient Market Hypothesis in the Indian Stock Market with respect to financial services industry by conducting an event study. The monetary policy announcements made from 11th March 2016 to 30th August 2019 are taken as the events. The event study methodology is conducted on 13 financial service companies listed in NSE Financial Services Index. The Average Abnormal Return (AAR) and Cumulative Average Abnormal Return (CAAR) are estimated using the daily closing price of the sample companies and Nifty. Two sample T-statistics are used to find the significance of the returns generated. The t-values of a majority of AARs and CAARs are significant suggesting that there is a scope for generating abnormal return by the investors on the event of the monetary policy announcement. It is found that the investors are able to earn abnormal profits which indicate that the Indian stock market is not efficient in the semi-strong form due to the slow absorption of information. IJSTR 2020. -
MONG: An extension to galaxy clusters
The presence of dark matter (DM), though well established by indirect evidence, is yet to be observed directly. Various DM detection experiments running for several years have yielded no positive results. In view of these negative results, we had earlier proposed alternate models by postulating a minimum gravitational field strength (minimum curvature) and a minimum acceleration. These postulates led to the modified Newtonian dynamics and modified Newtonian gravity (MONG). The observed flat rotation curves of galaxies were also accounted for through these postulates. Here, we extend these postulates to galaxy clusters and model the dynamical velocity-distance curve for a typical cluster such as the Virgo cluster. The radial velocities of galaxies in the Virgo cluster are also obtained through this model. Observations show an inconsistency in the Hubble flow at a mean cluster distance of 17 Mpc, which is expected in regions of high matter density. This decrease in velocity is predicted by our model of modified gravity (MONG). The radial velocity versus distance relation for galaxies in the Virgo cluster obtained using MONG is in agreement with observations. 2022 World Scientific Publishing Company. -
Monitoring and Controlling Data Through the Internet of Things (IOT) System: A Framework to Measure the Public Health
Associating and sharing information by means of the web between actual things, or 'things,' coordinated with sensors, programming, and different advances are known as the Internet of Things (IoT). In order to improve technology through IoT, there have been a number of important studies and investigations. This study exhibits how the Internet of Things might be utilized to screen wellbeing. In this research work, with the help of IoT based human wellbeing checking framework the information circulatory strain, beat rate, internal heat level, pulse, and other crucial signs are providing to the internet. The use of IoT for the human health monitoring system in later on future, need a very accurate assessment of risk and this is required to provide a long term information to the device. 2022 IEEE. -
Monitoring nyiragongo volcano using a federated cloud-based wireless sensor network
Current Nyiragongo Volcano observatory systems yield poor monitoring quality due to unpredictable dynamics of volcanic activities and limited sensing capability of existing sensors (seismometers, acoustic microphones, GPS, tilt-meter, optical thermal, and gas flux). The sensor node has limited processing capacity and memory. So if some tasks from the sensor nodes can be uploaded to the server of cloud computing then the battery life of the sensor nodes can be extended. The cloud computing can be used both for processing of aggregate query and storage of data. The two principal merits of this paper are the clear demonstration that the Cloud Computing model is a good fit with the dynamic computational requirements of Nyiragongo volcano monitoring and the novel optimization algorithm for seismic data routing. The proposed new model has been evaluated using Arduino-Atmega328 as hardware platform, Eucalyptus/Open Stack with Orchestra-Juju for Private Sensor Cloud connected to some famous public clouds such as Amazon EC2, ThingSpeak, SensorCloud and Pachube. 2017 IEEE. -
Monoclinic Y2O3: Ce nanophosphors synthesized by wet chemical precipitation method
UV emitting nanophosphors draws attention from many researchers currently due to the diverse applications ranging from UV LEDs to phototherapy. The current work is an investigation of monoclinic yttrium oxide doped with cerium synthesized by means of wet chemical precipitation at low temperature (90 C). Raman analysis and TEM experiments confirmed the formation of monoclinic phase and XPS analysis proves the presence of Ce3+ energy levels. UV experiments delivered strong absorption in the short UV region and photoluminescence experiments demonstrated the material's capability to emit in the long UV region. Surface area measurements by BET analysis established the relationship between the BET surface area and luminescence intensity. This emission range is suitable for therapeutical application especially for skin diseases which further extends the scope of the work. 2023 Elsevier Ltd and Techna Group S.r.l. -
Monoclinic yttrium oxide quantum dots surface modified by biotin for bioimaging applications
Semiconductor nanoparticles or quantum dots are one of the central topics of interest in material science research due to its size dependent physical and chemical characteristics and applications in different areas from display to biomedical fields. This work reports the first-time synthesis of biotin functionalized monoclinic yttrium oxide quantum dots at low temperature and its application in live cell imaging. The presence of biotin was confirmed through FTIR measurements. HRTEM analysis confirmed the formation of small spherical quantum dots with an average size of 3.8 nm. Zeta potential measurements gave a negative surface charge of -26.9 mV confirming colloidal stability. The quantum dots show sharp absorption in the short UV region and PL experiments delivered defect related intense blue fluorescence emission. The material is nontoxic to both normal (L929) and cancer (MCF 7) cells and the live cell imaging experiments performed on MCF 7 cells show specific binding to the cells and presented bright fluorescence emission from the cells thus confirming the applicability of the material in both display industry and cancer cell imaging. 2023 Elsevier B.V. -
Monopsonistic exploitation in contract farming: Articulating a strategy for grower cooperation
Contract farming has been considered a new hope to instil dynamism in third world agriculture. However, there remains serious concern whether small peasants will be able to benefit from this system since buyers may often be a single large or at most, few large corporations, a typical case of monopsony. In this paper we question the basis of the fears that are often raised in the literature. A clear analytical approach to understanding the (economic) meaning of monopsony helps us articulate a strategy for grower cooperation that could effectively deal with monopsony power in contract farming systems. Copyright 2007 John Wiley & Sons, Ltd. -
MOOCs: A disruptive teaching-learning process in interdisciplinary boundaries /
International Journal of Language & linguistics, Vol.1, Issue 2, pp.54-61, ISSN No: 2374-8869. -
More insights into bar quenching: Multi-wavelength analysis of four barred galaxies
The underlying nature of the process of star formation quenching in the central regions of barred disc galaxies that is due to the action of stellar bar is not fully understood. We present a multi-wavelength study of four barred galaxies using the archival data from optical, ultraviolet, infrared, CO, and HI imaging data on star formation progression and stellar and gas distribution to better understand the process of bar quenching. We found that for three galaxies, the region between the nuclear or central sub-kiloparsec region and the end of the bar (bar region) is devoid of neutral and molecular hydrogen. While the detected neutral hydrogen is very negligible, we note that molecular hydrogen is present abundantly in the nuclear or central sub-kiloparsec regions of all four galaxies. The bar co-rotation radius is also devoid of recent star formation for three out of four galaxies. One galaxy shows significant molecular hydrogen along the bar, which might mean that the gas is still being funnelled to the centre by the action of the stellar bar. Significant star formation is also present along the bar co-rotation radius of this galaxy. The study presented here supports a scenario in which gas redistribution as a result of the action of stellar bar clears the bar region of fuel for further star formation and eventually leads to star formation quenching in the bar region. 2020 ESO. -
More Than Legacy: Stalins Political Formula That Keeps DMK on Top
Stalins mix of legacy, governance, and resistance seems to have struck the right chord with the TN electorate. -
Morphological and Elemental Investigations on CoFeBO Thin Films Deposited by Pulsed Laser Deposition for Alkaline Water Oxidation: Charge Exchange Efficiency as the Prevailing Factor in Comparison with the Adsorption Process
Abstract: Mixed transition-metals oxide electrocatalysts have shown huge potential for electrochemical water oxidation due to their earth abundance, low cost and excellent electrocatalytic activity. Here we present CoFeBO coatings as oxygen evolution catalyst synthesized by Pulsed Laser Deposition (PLD) which provided flexibility to investigate the effect of morphology and structural transformation on the catalytic activity. As an unusual behaviour, nanomorphology of 3D-urchin-like particles assembled with crystallized CoFe2O4 nanowires, acquiring high surface area, displayed inferior performance as compared to coreshell particles with partially crystalline shell containing boron. The best electrochemical activity towards water oxidation in alkaline medium with an overpotential of 315 mV at 10 mA/cm2 along with a Tafel slope of 31.5 mV/dec was recorded with coreshell particle morphology. Systematic comparison with control samples highlighted the role of all the elements, with Co being the active element, boron prevents the complete oxidation of Co to form Co3+ active species (CoOOH), while Fe assists in reducing Co3+ to Co2+ so that these species are regenerated in the successive cycles. Thorough observation of results also indicates that the activity of the active sites play a dominating role in determining the performance of the electrocatalyst over the number of adsorption sites. The synthesized CoFeBO coatings displayed good stability and recyclability thereby showcasing potential for industrial applications. Graphic Abstract: [Figure not available: see fulltext.] 2021, The Author(s). -
Morphology-dependent supercapacitive properties of Co3O4 nanomaterials synthesized via coprecipitation and hydrothermal methods
The supercapacitive properties of Co3O4 nanocrystalline powders with two different morphologies synthesized by coprecipitation (referred to as Co3O4C) and hydrothermal (referred to as Co3O4-H) methods were compared and studied. The samples were analyzed for their phase purity, crystal structure, surface morphology, and surface area. Both samples were found to be single-phase nanostructures with a normal spinel-type cubic crystal structure (space group Fd3m), as indicated by Raman and XRD (X-ray diffraction) data analyses. TEM (Transmission electron microscopy) images clearly show that the Co3O4C sample exhibits spherical particles with a mean size of 10 nm. On the other hand, the Co3O4H sample shows a flower-like assembly of particles. The Co3O4C sample has a higher specific surface area than the Co3O4-H sample due to its smaller particle size. XPS (X-ray photoelectron spectroscopy) data were collected to analyze the chemical states and cation distribution of the samples, revealing a 2:1 ratio of Co3+ and Co2+ in both samples. Both samples displayed pseudocapacitive behaviour in CV (cyclic voltammetry) and GCD (galvanostatic chargedischarge) analyses. Despite having a smaller surface area, the Co3O4H electrode exhibited a higher CS (specific capacitance) compared to the Co3O4C electrode at all current densities when tested using 1 M KOH electrolyte. At a specific current density (0.5 A/g), the Cs values for Co3O4C and Co3O4H are found to be 366 F/g and 233 F/g, respectively. As the current density increases, the specific capacitance of both electrodes decreases, but this reduction is more prominent for Co3O4-C than Co3O4-H. The study indicates that besides surface area, the morphology of the sample also plays a crucial role in determining the capacitance of a material. 2023 Elsevier B.V.