Recent publications
Gloriosine, the predominant metabolite of Gloriosa superba L., shares chemical properties with colchicine. We analyze the microtubule-binding affinity of gloriosine at the colchicine binding site (CBS) using an in silico-in vivo approach. The In silico docking of gloriosine showed a binding score of (−) 7.5 kcal/Mol towards β-tubulin at CBS and was validated by overlapping the coupling pose of the docked ligand with co-crystallized colchicine. 2D plots (Ligplot +) showed > 85% overlap between gloriosine and colchicine. The ADMET profile of gloriosine was in accordance with Lipinski’s rule of five. Gloriosine belongs to class II toxicity with anLD50 value of 6 mg/kg. In vivo and transmission electron microscopy studies revealed that gloriosine induces abnormalities in cell division such as condensed chromosomes in C-metaphase and enlarged nucleus with increased nuclear material. Gloriosine treated cells exhibited mitotic index of about 14% compared to control of 24% and high anti-proliferative activity i.e. 63.94% cell viability at a low concentration (0.0004 mg/ml). We conclude that gloriosine has a strong affinity for β-tubulin at CBS and thus can be used as a colchicine alternative in cytology and other clinical conditions.
Selenium (Se) is an essential element for living systems, however, toxic at higher levels. In the present study, Dunaliella salina cells were exposed to different Se concentrations for their growth (EC50 195 mg L-1) as well as Se accumulation. The cells exposed to 50 mg L-1 Se showed photoautotrophic growth parallel to control and accumulated 65 μg Se g-1 DW. A decrease in photosynthetic quantum yield, chlorophyll content, and the increase in intracellular reactive oxygen species, proline content, and lipid peroxidation accompanied by higher neutral lipid accumulation, were recorded at higher Se level. The enzymes superoxide dismutase and catalase played a pivotal role in antioxidative defense. Heterogeneity in accumulated carotenoids at varying concentrations of selenium was prevalent. The cells exposed to 200 mg L-1 Se resulted in the disorganization of organelles. Thus, the Se enriched biomass obtained at 50 mg L-1 may be explored for bio-fortification of food and feed.
As the world struggles with the ongoing COVID-19 pandemic, unprecedented obstacles have continuously been traversed as new SARS-CoV-2 variants continually emerge. Infectious disease outbreaks are unavoidable, but the knowledge gained from the successes and failures will help create a robust health management system to deal with such pandemics. Previously, scientists required years to develop diagnostics, therapeutics, or vaccines; however, we have seen that, with the rapid deployment of high-throughput technologies and unprecedented scientific collaboration worldwide, breakthrough discoveries can be accelerated and insights broadened. Computational protein design (CPD) is a game-changing new technology that has provided alternative therapeutic strategies for pandemic management. In addition to the development of peptide-based inhibitors, miniprotein binders, decoys, biosensors, nanobodies, and monoclonal antibodies, CPD has also been used to redesign native SARS-CoV-2 proteins and human ACE2 receptors. We discuss how novel CPD strategies have been exploited to develop rationally designed and robust COVID-19 treatment strategies.
Alpha-cypermethrin, a pyrethroid pesticide, is frequently used on crops to prevent insect attacks. However, occasionally, due to drift, leaching, or with rainwater, it enters the aquatic environment and poses a serious threat to the growth of non-target aquatic organisms. In the current study, we were interested in investigating the damaging effect of alpha-cypermethrin on a local freshwater non-target green alga Chlorella sp. NC-MKM in terms of its protein levels. This was achieved by exposing Chlorella sp. NC-MKM to an EC50 concentration of alpha-cypermethrin for 1 day, followed by the two-dimensional (2-D) gel electrophoresis and MALDI-TOF MS. Fifty-three proteins, which had showed significant differential accumulation (> 1.5 fold, P < 0.05) after exposure to alpha-cypermethrin, were considered as differentially accumulated proteins (DAPs). These DAPs were further divided into several functional categories, and the expressions of each in control and treatment samples were compared. Comparison revealed that alpha-cypermethrin exposure affects the accumulation of proteins related with photosynthesis, stress response, carbohydrate metabolism, signal transduction and transporters, translation, transcription, cell division, lipid metabolism, amino acid and nucleotide biosynthesis, secondary metabolites production, and post-translational modification, and thus rendered the tested algal isolate sensitive toward this pesticide. The overall findings of this research thus offer a fundamental understanding of the possible mechanism of action of the insecticide alpha-cypermethrin on the microalga Chlorella sp. NC-MKM and also suggest potential biomarkers for the investigation of pesticide exposed microalgae.
In this work, the variation of the radioactivity at different depth of the soil found at the Sung Valley in West Jaiñtia Hills District of Meghalaya in India is estimated by using the gamma-ray spectroscopy. The average activity concentration of 226Ra, 232Th and 40K for soil samples at different depths are measured to be 57, 156 and 352 Bq kg−1, respectively. The radiological hazard indices for the soil samples are calculated using standard models in order to determine the safe utility of these materials that are being used to manufacture domestic products by the locals. Values of all the radiological hazard indices are observed to be within the internationally recommended values as proposed by the European Commission and the United Nations Scientific Committee on the Effects of Atomic Radiation. The present study ensures that the soil analysed presents a negligible radiation hazard, and produced poetries and artefacts radiological incidence will stay within the allowed natural limit.
As the 6LoWPAN devices in the Internet of Things (IoT) applications communicate sensitive information over the unattended and insecure channel, it is essential to design suitable authentication methods for such devices. Due to high computation and communication overheads, the traditional certificate-based authentication schemes are predominantly considered impractical for resource-constraint 6LoWPAN devices used in IoT applications. However, a certificate with some lightweight features makes the authentication feasible in those resource-constraint 6LoWPAN devices. This paper proposes a lightweight certificate-based authentication scheme based on cryptographic hash operation and elliptic curve digital signature algorithm. It can mitigate several security threats, including replay, man-in-the-middle, impersonation, malicious device deployment, and spoofing attacks. The automated validation of Internet security protocols and applications (AVISPA) verification tool is used to formally verify the security of the proposed scheme against several known attacks. In addition, the correctness of the authentication scheme is verified using the widely accepted BAN logic. Moreover, a comparative analysis among the proposed and other well-established relevant schemes is carried out in order to figure out the trade-off considering not only the functionality attributes and security but also the involved computation and communication costs.
The release of tetracycline hydrochloride (TCH) and methylene blue (MB) dye into the aquatic system uncontrollably caused major environmental and health problems; hence, their prevention required serious attention. Adsorption process is now being researched in order to increase adsorption efficiency and reprocess to alleviate environmental issues. The use of magnetic nanoparticle as an adsorbent for wastewater treatment has a lot of prospective. A magnetic iron oxide nanoparticle surface modified by Vasaka (Justicia adhatoda) leaf extract (JA-MIONs) is used to give a fast removal approach for MB dye and TCH antibiotics. Dynamic light scattering, UV–Vis and band gap measurement, powder X-ray diffraction, Fourier-transform infrared spectroscopy, and transmission electron microscopy were operated to analyse the formation and size of these magnetic nanoparticles. The impacts of different factors such as contact time (30–150 min), adsorbate concentration (10–50 mg/L), pH (4–10), and adsorbent dose (2–10 mg) were explored. Adsorption kinetics and isotherms show that it follows the pseudo-first-order kinetic and the Freundlich isotherm, with maximum adsorption capacities of 76.92 mg/g for MB and 200 mg/g for TCH at 298 K. The reusability of the JA-MIONs eventually exhibited a decline in the adsorption percentage of MB and TCH after five and four times respectively. After the desorption-adsorption cycles, this adsorbent continued to exhibit significant adsorption capacity. This investigation furnished the significant reference data for the synthesis of JA-MIONs as a novel and auspicious adsorbent for the industrial clean-up of toxic dyes and heavily used antibiotics from water.
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Affirmative action (AA) has long been viewed negatively in contemporary society. The political philosophies of AA are still widely misunderstood and fiercely debated around the world today. The argument against AA is that faculty hired through AA are less efficient than those hired through open/general category. This research attempts to empirically assess if professors from the Other Backward Class (OBC), Scheduled Caste (SC) and Scheduled Tribe (ST) categories in India’s three Central Universities are equally productive and effective as their General category counterparts. The effectiveness of the four teaching categories (General/OBC/SC/ST) was evaluated using the CCR model of Data Envelopment Analysis, while the productivity of teachers was estimated using bibliometric analysis. The data analysis demonstrates that AA positively impacts the research productivity of marginalized groups, except ST, which has very low representation in Pure and Applied Sciences, with OBC and SC performing on par with their General counterpart when placed in higher productivity subjects.
The microalga, Dunaliella salina, is a treasure of fine chemicals, carotenoids, and lipids of industrial importance. The present investigation focused on the maximization of lipid content in the context of biofuel. Mixotrophic cultures growing in different combinations of sodium bicarbonate (NaHCO3) and glucose (Glu) or sodium acetate (Na-Ace) were monitored for essential growth parameters such as photosynthesis, dry biomass, and Chl a content. The maximum photosynthetic quantum yield (Fv/Fm) of all the screened mixotrophic cultures along with control ranged between 0.63 and 0.72, indicating the cells were in a good physiological state. The highest biomass productivity (33.46 ± 0.58 mg/L/d) was recorded in 1.0 mM NaHCO3 + 1.0 mM Glu-containing cultures. However, the highest lipid content (56% DCW) was recorded in 1.0 mM NaHCO3 + 0.5 mM Na-Ace-containing cultures. Interestingly, a 1.7-fold higher starch content (72.3 μg/mL) was recorded in 0.25 mM NaHCO3 + 0.5 mM Na-Ace over 1.0 mM NaHCO3 + 0.5 mM Na-Ace-containing cultures. Thus, data indicated that the higher concentration of NaHCO3 along with Na-Ace favoured lipid biosynthesis, while the lower concentration of NaHCO3 with Na-Ace favoured starch synthesis. Thus, substrate provision determined the desired products. Lipids obtained from D. salina at stage II (nitrogen-deficient condition) possessed ideal fuel properties according to international standards of EN 14214 and ASTM D6751. Therefore, the present work explored the threshold level of bicarbonate along with Na-Ace which was able to maintain good physiological status and produced higher lipids with better biodiesel properties.
Graphical Abstract
The use of TiO2 nanoparticles for photocatalysis for the degradation of organic dyes under UV light for wastewater treatment has been widely studied. However, the photocatalytic characteristics of TiO2 nanoparticles are inadequate due to their UV light response and higher band gap. In this work, three nanoparticles were synthesized: (i) TiO2 nanoparticle was synthesized by a sol-gel process. (ii) ZrO2 was prepared using a solution combustion process and (iii) mixed-phase TiO2–ZrO2 nanoparticles were synthesized by a sol-gel process to remove Eosin Yellow (EY) from aqueous solutions in the wastewater. XRD, FTIR, UV-VIS, TEM, and XPS analysis methods were used to examine the properties of the synthesized products. The XRD investigation supported the tetragonal and monoclinic crystal structures of the TiO2 and ZrO2 nanoparticles. TEM studies identified that mixed-phase TiO2–ZrO2 nanoparticles have the same tetragonal structure as pure mixed-phase. The degradation of Eosin Yellow (EY) was examined using TiO2, ZrO2, and mixed-phase TiO2–ZrO2 nanoparticles under visible light. The results confirmed that the mixed-phase TiO2–ZrO2nanoparticles show a higher level of photocatalytic activity, and the process is accomplished at a high degradation rate in lesser time and at a lower power intensity.
Antimicrobial polypropylene (PP) was developed by plasma functionalization and subsequent immobilization of chitosan (CS)‐chlorhexidine (CHX) nanogels as the bioactive component. Oxygen plasma was used to create a hydrophilic surface monitored by water drop interaction with the fabric surface. CS nanogels were prepared by the ionic gelation method. The characterization of the nanogels was carried out by transmission electron microscopy (TEM) and energy dispersive X‐ray microanalysis (EDX). The functionalized fabric exhibited excellent antimicrobial nature against S. aureus and E. coli microbes. The animal studies involving mice showed that the material exhibited excellent biocompatibility in contact with the skin. There was no evidence of inflammatory cells in the histopathology. This investigation suggests that the fabric has enormous potential as infection‐resistant material in applications such as wet wipes. PP has been functionalized by oxygen plasma to create a hydrophilic surface. The bioactive nanogels of chitosan (CS)‐chlorhexidine (CHX) immobilized to develop antimicrobial fabric surfaces. The biofunctional PP surface is active against gram‐negative and gram‐positive bacteria.
A bis‐heteroleptic Ru(II) complex, 1[PF6]2 of a benzimidazole substituted pyridyl‐1,2,3‐triazole ligand (BiPT) for highly selective luminescence turn‐on detection of hypochlorous acid (HOCl) is reported. Detection of HOCl is achieved by the Markovnikov addition of HOCl to the C=C bond of 1,2,3‐triazole and a successive highly specific C(sp2)‐H chlorination at the C5 position of 1,2,3‐triazole. The chlorination at C5 in 1,2,3‐triazole is supported by high‐resolution mass spectrometry and 1H NMR study. 1[PF6]2 shows high sensitivity towards HOCl in PBS buffer (pH 7.4) containing 5 % acetonitrile with a 37‐fold luminescence light‐up and a detection limit as low as 7.5 μM. HOCl mediated C(sp2)‐H chlorination increases the 3MC‐3MLCT energy gap as well as the population of the 3MLCT excited state and exhibits the radiative decay from the excited state of 1. The probe showed low cytotoxicity and efficiently permeated the cell membrane. The cell‐imaging experiments revealed rapid staining of the HeLa cells in the presence of exogenous HOCl. A bis‐heteroleptic ruthenium (II) complex of benzimidazole substituted 1,2,3‐triazole‐based ligand has been developed for highly selective luminescent ‘light‐up detection of HOCl via unique C(sp2)‐H chlorination.
Little is known about the existing gender disparities in library and information science research. The current study aims to analyze research articles from the Annals of Library and information studies journal from a gender perspective. The study looked at the author’s position in relation to their gender, various patterns of collaboration, and if this has affected citations. This study also attempts to determine the male and female authors’ research interests as the first author. The data were gathered from the Scopus database between 2011 and 2019 and were quantified using bibliometrics. Six distinct authorship patterns were recognized. The findings reveal men in first and last author positions constitute the highest research articles and citations indicating male authors to be more influential compared to females. Additionally, the study findings have provided an overview of the current state of women in library and information science research and highlighted areas where improvements can be made.
The present research work represents the numerical study of the device performance of a lead-free Cs2TiI6−XBrX-based mixed halide perovskite solar cell (PSC), where x = 1 to 5. The open circuit voltage (VOC) and short circuit current (JSC) in a generic TCO/electron transport layer (ETL)/absorbing layer/hole transfer layer (HTL) structure are the key parameters for analyzing the device performance. The entire simulation was conducted by a SCAPS-1D (solar cell capacitance simulator- one dimensional) simulator. An alternative FTO/CdS/Cs2TiI6−XBrX/CuSCN/Ag solar cell architecture has been used and resulted in an optimized absorbing layer thickness at 0.5 µm thickness for the Cs2TiBr6, Cs2TiI1Br5, Cs2TiI2Br4, Cs2TiI3Br3 and Cs2TiI4Br2 absorbing materials and at 1.0 µm and 0.4 µm thickness for the Cs2TiI5Br1 and Cs2TiI6 absorbing materials. The device temperature was optimized at 40 °C for the Cs2TiBr6, Cs2TiI1Br5 and Cs2TiI2Br4 absorbing layers and at 20 °C for the Cs2TiI3Br3, Cs2TiI4Br2, Cs2TiI5Br1 and Cs2TiI6 absorbing layers. The defect density was optimized at 1010 (cm−3) for all the active layers.
Biocompatible quantum dots (QDs) have attracted a lot of attention due to their potential biological applications (drug delivery, sensing and diagnosis). Here, we have synthesized 2-4 nm sized biocompatible zinc sulphide (ZnS) QDs using a plant leaf extract as an immobilizing and stabilizing agent via a green route. We have investigated the biological effects of ZnS QDs in a variety of applications, including (1) anti-bacterial activity, (2) cell cytotoxicity, (3) bio-sensing and (4) protein binding. Studies on the anti-bacterial activity of the as-synthesized ZnS QDs against E. coli and E. faecalis inhibited bacterial growth effectively and showed a cytotoxic effect on the HeLa cell line. The biosynthesized ZnS QDs act as a fluorescence probe to detect bilirubin and rifampicin (RFP) with a wide linear range, high sensitivity, good selectivity, and a low limit of detection (LOD), with LOD values of 22.12 ± 0.25 ng mL-1 and 122.37 ± 0.42 ng mL-1, respectively. In a biological matrix, the QDs can form a complex with biomacromolecules; therefore, we studied the interaction between a carrier protein (HSA) and the as-synthesized ZnS QDs. The surface functionalized and nano-sized ZnS-GT QDs were observed to form complexes with the human serum albumin (HSA) protein and quenched the intrinsic fluorescence of HSA through static and dynamic quenching modes. The binding affinity was observed to be of the order of 105 M-1 for the HSA-ZnS-GT QD interactions, which can be considered as a reversible mode of binding. The effect of the ZnS QDs on other ligands and protein interactions was also studied. Enhanced binding affinities for HSA-quercetin ((5.994 ± 0.139) × 105 M-1) and HSA-luteolin ((3.068 ± 0.127) × 105 M-1) interactions were also observed in the presence of ZnS-GT QDs.
Dam building holds high in India’s state development agendas. It signifies a certain kind of developmentalism that does not seem to have lost its appeal since the early days of independence. The legitimisation of large hydro energy as green, clean, reliable and sustainable is widely contested. Participatory decision-making by affected people in developmental projects like large dams is often considered impossible, in spite of its support and advocacy by the World Commission on Dams. The report of WCD 2000, described as ‘new framework for decision-making’, centred on ‘rights and risks’ approach, has been able to draw global attention to the fact that decisions regarding large dams are not restricted to merely structural design or physical description. There are other equally significant and associated aspects that have not received due attention. Drawing from an extensive study on Lower Subansiri Hydropower Project (LSHP) in Assam, this chapter seeks to understand if community participation is considered significant, particularly by the people who would be directly affected by the project. The primary source of data collection includes a multisited ethnographic account of the field of contestations, including the downstream and upstream of the dam construction, their notion of development and the various organisations representing different sections of the society involved in the protests. The aim here is to analyse the multilevel decision-making process so as to determine why, how and whether planning and decision-making has been opening up to diverse societal interests like resettlement and rehabilitation, ecological sustainability and public involvement in the decision-making processes.
Herein, we systematically studied the electronic, optical, and mechanical properties of a hydrogenated (6,0) single-walled carbon nanotube [(6,0) h-SWCNT] under applied uniaxial stress from first-principles density functional theory (DFT) and molecular dynamics (MD) simulation. We have applied the uniaxial stress range from -18 to 22 GPa on the (6,0) h-SWCNT (- sign indicates compressive and + indicates tensile stress) along the tube axes. Our system was found to be an indirect semiconductor (Γ-Δ), with a band gap value of ∼0.77 eV within the linear combination of atomic orbitals (LCAO) method using a GGA-1/2 exchange-correlation approximation. The band gap for (6,0) h-SWCNT significantly varies with the application of stress. The indirect to direct band gap transition was observed under compressive stress (-14 GPa). The strained (6,0) h-SWCNT showed a strong optical absorption in the infrared region. Application of external stress enhanced the optically active region from infrared to Vis with maximum intensity within the Vis-IR region, making it a promising candidate for optoelectronic devices. Ab initio molecular dynamics (AIMD) simulation has been used to study the elastic properties of the (6,0) h-SWCNT which has a strong influence under applied stress.
A red emissive ruthenium(II) complex 1[PF6]2 of an amino ethanol substituted 1,10-phenanthroline-based ligand (L1) has been developed and characterized by spectroscopic analysis and single-crystal X-ray diffraction. Complex 1 shows an aggregation-induced emission (AIE) enhancement and forms nano-aggregates in the poor solvent water and highly dense polyethylene glycol (PEG) media. The possible reason behind the AIE properties may be the rigidity gained through weak supramolecular interactions between neighbouring phenanthroline ligands and PF6- counterions. The AIE properties were supported by UV-vis and photoluminescence (PL) spectroscopy and dynamic light scattering (DLS) studies to substantiate the formation of nano-aggregates and to understand the morphology of the aggregated particles, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) studies were performed. Compound 1[PF6]2 was highly selective towards pyrophosphate ions (PPi) over other phosphates such as ATP, ADP, AMP and H2PO4- ions and other competitive anions in the PL spectroscopic channel in acetonitrile. The PL titrations of 1[PF6]2 with PPi in CH3CN furnished the association constant Ka = 1.08 × 104 M-1 and the detection limit was calculated as low as 1.54 μM. The PPi detection has been established through the unique H-bonding interaction, supported by 1H NMR titration. Finally, the cytotoxicity study and bioimaging were carried out for biological application. The complex shows very low cytotoxicity and good biocompatibility and is suitable for intracellular PPi imaging.
Fixation of atmospheric CO2 into value-added products is a promising methodology. A series of novel nickel(II) complexes of the type [Ni(L)(CH3CN)2](BPh4)21 - 5, where L= N,N-bis(2-pyridylmethyl)-N',N'-dimethylpropane-1,3-diamine (L1), N,N-dimethyl-N'-(2-(pyridin-2-yl)ethyl)-N'-(pyridin-2-ylmethyl) propane-1,3-diamine (L2), N,N-bis((4-methoxy-3,5-dimethylpyridin-2-ylmethyl)-N',N'-dimethylpropane-1,3-diamine (L3), N-(2-(dimethylamino) benzyl)-N',N'-dimethyl-N-(pyridin-2-ylmethyl) propane-1,3-diamine (L4) and N,N-bis(2-(dimethylamino)benzyl)-N',N'-dimethylpropane-1,3-diamine (L5) have been synthesized and characterized as the catalysts for the conversion of atmospheric CO2 into organic cyclic carbonates. The single-crystal X-ray structure of 2 was determined and exhibited distorted octahedral coordination geometry with cis-α configuration. The complexes were employed as a catalyst for the conversion of CO2 and epoxides into five-membered cyclic carbonates under 1 atmospheric (atm) pressure at room temperature in the presence of Bu4NBr. The catalyst containing electron-releasing -Me and -OMe groups afforded the maximum yield of cyclic carbonates, 34% (TON, 680) under 1 atm air. It was drastically enhanced to 89% (TON, 1780) under pure CO2 gas at 1 atm. It is the highest catalytic efficiency known for CO2 fixation using nickel-based catalysts at room temperature and 1 atm pressure. The catalytic efficiency is strongly influenced by the electronic and steric factors of the ligands. Furthermore, all the catalysts can convert a wide range of epoxides (ten examples) into corresponding cyclic carbonate with excellent selectivity (>99%) under this mild condition.
The scientific and technical sectors saw the necessity for innovative solutions as the effects of COVID-19 on society became clear. More basic research endeavors with long-term and significant effects have focused on the creation of novel diagnostics and the acceleration of vaccines. Researchers from many walks of life got together to tackle this problem in a truly global effort. In the medium term, efforts have focused on repurposing current technologies and utilizing additive manufacturing techniques to overcome shortages in safety equipment and disinfection. The development of innovative diagnostics and the acceleration of vaccines have been the focus of more basic research initiatives with an impact in the middle and lengthy. As a vital technology, photonics has supported all efforts, both directly and indirectly, to combat this type of pandemic. This viewpoint will provide an outline of the crucial part the photonics society played in the COVID-19 pandemic and talk about how the photonics society could assist in preventing future pandemic viruses.
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