Search

Natural Kosa silk is one of the textile fibers to be used in apparel application. Since it is proteinous and hygroscopic fiber and gets affected easily by microbes during usage and storage. Hence, this special type of silk produced in Chhattisgarh state of India, needs to be treated for the antimicrobial treatment for its better applications in various fields. Therefore, in the present work, the Kosa silk was modified by grafting of quaternary ammonium compound-containing monomer through thermo-chemical route. Experimental conditions for achieving optimum grafting of ionic monomer [2-(methacryloyloxy)ethyl] trimethyl ammonium chloride (MAETC) was investigated. Redox combination of ceric ammonium nitrate as a redox initiator and nitric acid (HNO3) as catalyst, by successively varying reaction conditions like concentration of initiator, catalyst and desired monomers under optimized reaction conditions were performed. The grafted silk material was characterized by Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIR) and X-Ray Diffraction Analysis (XRD) techniques. The antibacterial study of grafted silk material having quaternary ammonium groups is an emerging group of antibacterial agents, which can be used as disinfectants. Using agar well method demonstrated that the grafted silk (KS-g-MAETC) inhibited the growth of Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. As this grafted silk material has potent antibacterial activity, it may be used in the garment industry as well as for various biomedical applications, thus, serving the humanity. [ABSTRACT FROM AUTHOR]

Global warming and environmental pollution issues are the challenges that have prompted researchers around the world to recognize biodegradable material as an alternate solution for fossil fuel dependency. The previous literature motivates the researchers to identify alternatives to artificial reinforcement in composite materials. This work utilizes Calotropis gigantea fiber as a strengthening agent, which is generously available as an unused plant in India. Compression molding technique was used for the preparation of specimens with different fiber orientation (0°, 15°, 30°, 45°, 60°, 75°, 90°, 0°/90°, and 0°/45°/90°) Specimen with 0° fiber orientation registered a maximum value of 142.46 MPa, 93.13MPa, and 81.21 kJ/m2 in Flexural test, Tensile test and Impact test, respectively, than the other orientations. Mechanical testing results establish that the orientation of the fiber will prominently influence in improving the strength. The thermal studies on Calotropis gigantea fiber-epoxy composites through Thermogravimetric Analysis and Differential Scanning Calorimetry reveal that the composite will withstand more than 600°C temperature and confirm its thermal stability. The combined findings show that Calotropis gigantea fiber in polymer composite can be a possible reinforcing material and suitable for manufacturing accessories for automobile and household applications. [ABSTRACT FROM AUTHOR]

Extracellular polymeric substances (EPS) are complex, hydrated matrices produced by biofilm-forming bacteria to anchor themselves to surfaces and resist antibiotic treatment. EPS plays a critical role in the formation, maintenance and virulence of biofilms, leading to persistent infections and posing significant challenges in healthcare. Characterizing bacterial EPS is essential to understand their biochemical composition and functional properties, which is critical for optimizing their applications in biotechnology, medicine, and environmental management. Therefore, the present study aimed to isolate and screen the bacteria from Arabian Sea for their ability to produce EPS from biofilm surfaces. Additionally, the detailed characterization of the EPS was also carried out. These bacteria were identified using 16S rRNA gene sequence analysis and revealed that all the EPS-producing bacterial isolates belong to different bacterial genera (Oceanimonas, Psychrobacter and Vibrio). The bacteria were cultured on Zobell marine broth media and EPS were isolated using the propanol precipitation method. The EPS weight varied among the bacterial isolates and ranged from 0.81 g L−1 to 2.21 g L−1. The EPS produced by the bacterial strains have shown antimicrobial as well as free radicals (2,2-diphenyl-1-picrylhydrazyl; DPPH) and 2, 2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging activity. The antimicrobial and free radical scavenging properties of EPS have promising biotechnological applications in developing new antibiotics, enhancing food preservation, creating protective coatings, and improving wound healing therapies. The Fourier-transform infrared spectroscopy (FTIR) revealed the presence of aliphatic methyl, halide groups, saccharides and primary amines. Gas chromatography equipped with mass spectroscopy (GC–MS) confirmed the presence of monosaccharides such as glucose, galactose, arabinose and mannose. The EPS were further characterized using X-Ray diffraction (XRD), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The study highlights the importance of EPS in biofilm formation, antibiotic resistance and persistent infections, emphasizing the importance of isolating and characterizing of EPS for its potential biotechnological applications, including antimicrobial and free radical scavenging activities. [ABSTRACT FROM AUTHOR]

The main aim of this study was to enhance the dissolution rate of BCS class II drug Indomethacin (IND) by solid dispersion (SD) techniques using Ocimum basilicum mucilage (OBM) as a carrier. Solid dispersions of indomethacin were prepared by using Ocimum basilicum mucilage by four different methods. Effect of methods of preparation on dissolution rate was studied. It was found that the dissolution rate of IND from its SD was dependent on the method of preparation of solid dispersions. Dissolution study revealed that the physical mixture and kneading method were convenient and effective methods for dissolution enhancement of poorly water soluble drug IND, among various methods of preparation of SD. The prepared SD's were characterized by FTIR, Differential Scanning Calorimetry, and X-ray diffraction studies. From the study we conclude that OBM could be used as a potential carrier in enhancing the dissolution rate and ultimately bioavailability of IND. [ABSTRACT FROM AUTHOR]

Mine fire is a major problem for the Indian coal mining industry and exists since beginning of the mining. A huge amount of the prime coking coal reserves of different coalfields are blocked due to existence of fire and thus cannot be extracted without extinguishing it. Many approaches have been attempted in this direction to minimize this socio-technological problem. Use of chemical retardants to inhibit smouldering combustion phenomenon is an important method, which can be adopted to prevent or delay its occurrences. In this situation, it may sometimes be necessary to use fire retardants for reducing the intensity of fire so that the coal production will not be hampered. This paper presents the impact of chemical additives on coal oxidation process, studied from the mechanistic perspective aiming to search effective retardant materials to prevent and control coal self-heating phenomenon. A numbers of chemicals and combinations along with coal, which are moderately prone to smouldering combustion, were studied to determine its efficacy to prevent and combat it. In the process CPT, IPT and DSC study of coal samples and chemicals were observed. Based on the results, suitable retardants were selected and mixed with coal samples. The mixtures were further analysed for above properties. Finally, the best suitable combination of inhibitors were determined and applied in the field, which gave desired results. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the color, rheology and thermal properties of commercial honey in India. Findings reveal that the color of Indian honey samples varied from white to light amber, while viscosities ranged from 1.31 to 96.7. Results from the differential scanning calorimetry analysis showed that the inflection transition temperature (Tg) ranged between -51.40 and -30.64 degree Celsius.

The elemental composition of actual High-level Liquid Waste (HLW) received from reprocessing plant was estimated from analysis of several samples by using Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES). Based on the composition, the simulated waste (20–30 wt % based on oxide content) was prepared and vitrified in SiO 2 ·Na 2 O·B 2 O 3 ·TiO 2 ·Fe 2 O 3 glass system. Simulated Vitrified Waste Products (SVWPs) were characterized for their structural changes and relative thermal properties by using Infra-red (IR) spectrometry, X-ray Diffraction (XRD) and Differential Scanning Calorimetry (DSC) techniques. The measure of BO 3 , BO 4 , and Si−O−Si functional groups were found to be decisive in thermal and chemical durability of the products. Leach rate (LR Na) was found to be 10−5−10−6 g/cm2 day for ≤26% waste oxide (WO) loaded SVWPs. The relative increase in surface area by imparting 1 J of energy to the SVWPs was found to be < 1.4. For the optimized feed composition (24% waste oxide), the required activation energy (E a) for feed to glass conversion (50–200 kJ/mol) was estimated by DSC based advanced isoconversional method. Excellent surface and elemental homogeneity, internationally acceptable chemical durability (IAEA 28 days test) based on Na+ leach rate (3.5 × 10−6 g/cm2 day), generation of <0.5% respirable fines (<15 μm) during impact studies, of the SVWP from Joule Heated Ceramic Melter (JHCM) reveals that the optimized composition and its products are well qualified for safe operation, transit, and disposal. • First & detailed investigation of HLW vitrification at WIP, Kalpakkam, India. • The reaction mechanism for the formation of the VWP visualized. • The activation energy for feed to product established. • Product suitability for safe interim storage and final disposal established. [ABSTRACT FROM AUTHOR]

Co-amorphous drug–drug systems have been developed with the overall aim of improving the physical stability of two or more amorphous drugs. Co-amorphous systems often show good physical stability, and higher solubility and dissolution rates compared to their crystalline counterparts. The aim of this study is to determine if eutectic mixtures of two drugs can form stable co-amorphous systems. Three drug–drug mixtures, indomethacin–naproxen (IND−NAP), nifedipine–paracetamol (NIF−PAR), and paracetamol–celecoxib (PAR−CCX), were investigated for their eutectic and co-amorphization behavior as well as their physical stability in the co-amorphous form. The phase diagrams of the crystalline mixtures and the thermal behavior of the co-amorphous systems were analyzed by differential scanning calorimetry. The solid-state form and physical stability of the co-amorphous systems were analyzed using X-ray powder diffractometry during storage at room temperature at dry conditions. Initial eutectic screening using nifedipine (NIF), paracetamol (PAR), and celecoxib (CCX) indicated that IND−NAP, NIF−PAR, and PAR−CCX can form eutectic mixtures. Phase diagrams were then constructed using theoretical and experimental values. These systems, at different drug-to-drug ratios, were melted and cooled to form binary mixtures. Most mixtures were found to be co-amorphous systems, as they were amorphous and exhibited a single glass transition temperature. The stability study of the co-amorphous systems indicated differences in their physical stability. Comparing the phase diagrams with the physical stability of the co-amorphous mixtures, it was evident that the respective drug–drug ratio that forms the eutectic point also forms the most stable co-amorphous system. The eutectic behavior of drug–drug systems can thus be used to predict drug ratios that form the most stable co-amorphous systems. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to evaluate the cyclic fatigue resistance of 3 replicalike rotary instruments compared with their original brand systems using continuous rotation and optimum torque reverse (OTR) kinematics., Methods: New F1 rotary instruments (n = 20 per group) from ProTaper Universal (Dentsply Maillefer, Ballaigues, Switzerland) and ProTaper Gold (Dentsply Maillefer) original brand systems were compared with 3 replicalike instruments (U-File [Dentmark, Ludhiana, India], Super Files [Shenzhen Flydent Medical, Shenzhen, China], and Super Files Blue [Shenzhen Flydent Medical]) regarding cyclic fatigue resistance. In each group, the selected instruments were randomly distributed into 2 subgroups (n = 10) according to the kinematics. In the rotary group (ROT), the instruments were activated with a continuous clockwise rotation (300 rpm, 1.5 Ncm), whereas in the OTR group, asymmetric oscillatory motion was performed setting the OTR function at 300 rpm and adjusting the torque limit at the minimum level using the TriAuto ZX2 motor (J Morita, Kyoto, Japan). The time to fracture was recorded and statistically compared according to the kinematics (ROT × OTR) and the instrument type (replicalike × original brand) using the independent sample t test (α = 0.05). Additionally, the metal alloy characterization of each system was performed by differential scanning calorimetry and energy-dispersive X-ray spectroscopy., Results: Statistical analysis revealed significantly higher time to fracture for all rotary systems tested in OTR motion compared with continuous rotation (P < .05) with a mean percentage increase ranging from 52.1% (ProTaper Gold) to 156.7% (U-File). The replicalike instruments showed a significantly higher time to fracture compared with the respective original brand instruments in either ROT or OTR motion (P < .05). Replicas presented austenitic temperatures above the ones displayed by the original brands and an almost equiatomic ratio between nickel and titanium elements., Conclusions: OTR motion significantly improved the fatigue resistance of both original and replicalike systems. The replicas showed higher cyclic fatigue resistance than original brand instruments and higher transition temperatures to the austenitic phase., (Copyright © 2020 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Summary Nipah virus is a highly lethal zoonotic pathogen found in Southeast Asia that has caused human encephalitis outbreaks with 40%–70% mortality. NiV encodes its own RNA-dependent RNA polymerase within the large protein, L. Efficient polymerase activity requires the phosphoprotein, P, which tethers L to its template, the viral nucleocapsid. P is a multifunctional protein with modular domains. The central P multimerization domain is composed of a long, tetrameric coiled coil. We investigated the importance of structural features found in this domain for polymerase function using a newly constructed NiV bicistronic minigenome assay. We identified a conserved basic patch and central kink in the coiled coil that are important for polymerase function, with R555 being absolutely essential. This basic patch and central kink are conserved in the related human pathogens measles and mumps viruses, suggesting that this mechanism may be conserved. Graphical Abstract Highlights • A basic patch in the NiV phosphoprotein is essential for polymerase function • The central kink in the NiV phosphoprotein is essential for polymerase function • The basic patch and central kink are conserved in Nipah, mumps, and measles viruses The highly pathogenic Nipah virus, which caused a lethal outbreak in India in 2018, encodes its own polymerase complex. Bruhn et al. identified a basic patch essential for polymerase function in the phosphoprotein component of this complex. Interestingly, this patch is conserved across several genera within the Paramyxoviridae family. [ABSTRACT FROM AUTHOR]