Publications by authors named "Das Arindam"

A visible-light-induced photocascade strategy is disclosed for the synthesis of -dihydrofuro[3,2-]chromen-4-one scaffolds. The photocascade consists of electron donor-acceptor (EDA) complex enabled formation of arylidene coumarinone, followed by 1,4-radical conjugate addition (1,4-RCA) of an generated pyridinium ylide radical (PyYR) towards diastereoselective formation of the -dihydrofuro[3,2-]chromen-4-one scaffold in good to excellent yield. Thorough mechanistic investigations comprising photophysical, spectroscopic, electrochemical and DFT studies provide further insights into the reaction mechanism.

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The global COVID-19 pandemic has highlighted the need for rapid, reliable, and efficient detection of biological agents and the necessity of tracking changes in genetic material as new SARS-CoV-2 variants emerge. Here, we demonstrate that RNA-based, single-molecule conductance experiments can be used to identify specific variants of SARS-CoV-2. To this end, we (i) select target sequences of interest for specific variants, (ii) utilize single-molecule break junction measurements to obtain conductance histograms for each sequence and its potential mutations, and (iii) employ the XGBoost machine learning classifier to rapidly identify the presence of target molecules in solution with a limited number of conductance traces.

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Interaction under amyloidogenic condition between naturally occurring protoberberine alkaloid palmatine and hen egg white lysozyme was executed by adopting spectrofluorometric and theoretical molecular docking and dynamic simulation analysis. In spetrofluorometric method, different types of experiments were performed to explore the overall mode and mechanism of interaction. Intrinsic fluorescence quenching of lysozyme (Trp residues) by palmatine showed effective binding interaction and also yielded different binding parameters like binding constant, quenching constant and number of binding sites.

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Background: One of the most important aspects of women's well-being and welfare is RSH (reproductive and sexual health). Reproductive health is not an exception to the threat that CCC (climate change and climate crisis) poses to numerous facets of public health. Firstly, the present review seeks to identify the influence of climatic changes, natural disasters, and climate-driven migration on RSH.

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The radioligand [F]FPEB, used for PET imaging of the brain's metabotropic glutamate receptor subtype 5 (mGluR5), undergoes a thorough validation process to ensure its safety, efficacy, and quality for clinical use. The process starts by optimizing the synthesis of [F]FPEB to achieve high radiochemical yield and purity. This study focuses on optimizing the radiolabeling process using an aryl-chloro precursor and validating the GMP production for clinical applications.

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In this work we have studied the interaction of the food dye Indigo-Carmine (IndC) with the most studied model transport proteins i.e. human and bovine serum albumin (HSA & BSA).

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Purpose: Any instrumentation on the tooth surface for plaque or calculus removal will cause some amount of roughness on the tooth surface. Hence, this study was proposed to investigate the effects of hand and ultrasonic scaling and root planing on enamel and cementum, respectively.

Materials And Methods: Forty tooth samples were prepared from extracted maxillary and mandibular first pre-molars and were divided randomly into four groups of 10 samples each.

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A novel 8-hydroxy quinoline-derived amide receptor, in conjunction with its Cu (II) and Zn (II) complexes, has been strategically developed to function as remarkably efficient fluorescent receptors with a distinct capability for anion sensing. The comprehensive characterization of the synthesized compounds were achieved through UV-Vis, IR, NMR, and HRMS spectroscopic techniques. Among the Cu (II) and Zn (II) complexes, the latter exhibits superior selectivity for anions, specifically dihydrogen phosphate and hydrogen sulfate, as their tetrabutylammonium salts in a 9:1 acetonitrile-water (v/v) mixture.

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The effect of ionic strength on the aggregation of planar dyes like nile red (NR) and coumarin-30 (C30) in aqueous medium has been explored. The dyes are known to undergo dimerization, resulting in fading of their respective colors in the visible range. The present study demonstrates that the fading process is accelerated appreciably upon increasing ionic strength of the solution through addition of soluble salts.

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Clathrate hydrate is a naturally occurring icelike solid that forms in the water phase under suitable temperature and pressure conditions in the presence of one or more hydrophobic molecules. It also forms inside the oil and gas pipes, leading to higher pumping cost, flow blockage, and even catastrophic accidents. Engineered surfaces with low hydrate adhesion can provide an effective solution to this problem.

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Deoxyribonucleic acid (DNA) has emerged as a promising building block for next-generation ultra-high density storage devices. Although DNA has high durability and extremely high density in nature, its potential as the basis of storage devices is currently hindered by limitations such as expensive and complex fabrication processes and time-consuming read-write operations. In this article, we propose the use of a DNA crossbar array architecture for an electrically readable read-only memory (DNA-ROM).

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Background Vitamin D levels are strongly associated with myocardial infarction, coronary artery disease, heart dysfunction, and even mortality. Non-alcoholic fatty liver disease (NAFLD) is a prevalent hepatic illness whose incidence has grown dramatically over the past several decades. Methodology This observational, cross-sectional study was conducted over 1.

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A mild and eco-friendly visible-light-induced synthesis of 2-(2-hydrazinyl) thiazole from readily accessible thiosemicarbazide, carbonyl, and phenacyl bromide in the absence of a metal catalyst and/or any extrinsic photosensitizer is reported. This approach only requires a source of visible light and a green solvent at room temperature to produce the medicinally privileged scaffolds of hydrazinyl-thiazole derivatives in good to outstanding yields. Experimental studies support the formation of a visible-light-absorbing, photosensitized colored ternary EDA complex.

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Purpose: To explore a minimally invasive trans-canal endoscopic facial nerve decompression for traumatic facial nerve palsy and compare it with microscopic facial nerve decompression.

Methods: 35 and 38 patients underwent endoscopic and microscopic facial nerve decompression, respectively, for traumatic facial nerve palsy. Onset of symptoms, type of temporal bone fracture, day of surgical intervention following trauma, ossicular chain status and nature of insult to facial nerve were observed.

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A new quercetin-based iron(III) cationic complex [Fe()Cl(HO)(MeO)] (complex ) is created in the current study by condensation of quercetin with ferric chloride in the presence of EtN. Comprehensive spectroscopic analysis and conductometric measurement are used to pinpoint complex . The generated complex's +3-oxidation state has been verified by electron paramagnetic resonance (EPR) research.

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Background: Menstrual hygiene practices are somewhat poor among pre-menstrual aged rural women, and thereby, they are likely to be affected by menstrual and gynaecological morbidities. Hence, an attempt is made to comprehend the magnitude of menstrual hygiene practices through an index among rural women and identify its principal determinants.

Methods: Adopting a community-based cross-sectional study design, the required data was collected (through a semi-structured interview schedule) from 780 married pre-menopausal women (aged 35-49 years) from 30 villages of the Puducherry district during January-April 2021.

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The first step toward providing treatment, is getting the right diagnosis in real time; before it is too late. Without this, resource deployment may appear to be comparable to the scale and scope of the problem, while in reality it may just be a drop in the ocean. Maternal depression, during pregnancy is a debilitating risk to both the mother and the child, but the bigger problem is, it goes unnoticed, undetected, and therefore untreated.

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Background: Aging of population is a worldwide phenomenon of the 21 century, which leads to many socioeconomic consequences including their health status. Hence, this study tries to assess the self-reported health status (SRHS) of elderly widows (60+ years) and its principal determinants.

Materials And Methods: A cross-sectional study was conducted among 360 elderly widows from Puducherry district, 260 urban and 130 from rural areas.

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Steady-state and time-resolved spectroscopic studies demonstrate that two members of the coumarin class of dyes, coumarin 7 (C7) and coumarin 30 (C30), undergo self-aggregation in water. The development of hypsochromically shifted new absorption bands in addition to the existing monomer bands with an increase in concentration of the dyes in an aqueous medium suggests that the aggregates are of H-type. An absorption-based kinetic study reveals that the rate of aggregation of C30 is an order of magnitude faster than that of C7.

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Background: The all-electronic Single Molecule Break Junction (SMBJ) method is an emerging alternative to traditional polymerase chain reaction (PCR) techniques for genetic sequencing and identification. Existing work indicates that the current spectra recorded from SMBJ experimentations contain unique signatures to identify known sequences from a dataset. However, the spectra are typically extremely noisy due to the stochastic and complex interactions between the substrate, sample, environment, and the measuring system, necessitating hundreds or thousands of experimentations to obtain reliable and accurate results.

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Electrolysis is seen as a promising route for the production of hydrogen from water, as part of a move to a wider "hydrogen economy". The electro-oxidation of renewable feedstocks offers an alternative anode couple to the (high-overpotential) electrochemical oxygen evolution reaction for developing low-voltage electrolysers. Meanwhile, the exploration of new membrane materials is also important in order to try and reduce the capital costs of electrolysers.

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Introduction: The COVID-19 pandemic has impacted biopsychosocial health and wellbeing globally. Pre-pandemic studies suggest a high prevalence of common mental disorders, including anxiety and depression in South Asian countries, which may aggravate during this pandemic. This systematic meta-analytic review was conducted to estimate the pooled prevalence of anxiety and depression in South Asian countries during the COVID-19 pandemic.

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Defect chemistry in SnO is well established for resistive sensors but remains to be elusive for photoluminescence (PL) sensors. It demands a comprehensive understanding of the role of cationic and oxygen defects as well as the creation of abundant such defects to provide a selective PL signal. To accomplish it, SnO quantum dots (QDs ∼ 2.

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Background: Mastoidectomy is associated with extensive bone-drilling which makes it a major aerosol generating procedure. Considering the ongoing COVID-19 global pandemic, it is essential to devise methods to minimize aerosolization and hence ensure safety of the healthcare workers during the operative procedure.

Methods: Two disposable surgical drapes are used to create a closed pocket prior to commencement of mastoid bone-drilling.

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Statement Of Problem: Programming semiadjustable and fully adjustable articulators involves time-consuming clinical steps which can be avoided if an accurate radiographic method can accurately determine the condylar guidance angles.

Purpose: The purpose of this clinical study was to compare the sagittal condylar guidance in dentate individuals as determined by a clinical method, protrusive interocclusal record, and a radiographic method, cone beam computed tomography. If the methods show a correlation, then cone beam computed tomography can be used as a time-saving method of programming an articulator for patients requiring a cone beam computed tomography scan.

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