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It is shown that the dust density regimes in the dusty plasma are characterized by two complementary screening processes: (i) the low dust density regime where the Debye screening is the dominant process and (ii) the high dust density regime where the "Coulomb screening" is the dominant process. The Debye regime is characterized by a state where all dust particles carry an equal and constant charge. The high dust density regime or the "Coulomb plasma" regime is characterized by (a) "Coulomb screening" where the dust charge depends on the spatial location and is screened by other dust particles in the vicinity by charge reduction, (b) "asymptotic freedom" where dust particles, which on an average carry minimal electric charge, are asymptotically free in the high dust density limit, (c) uniform dust charge density and plasma potential, (d) dust charge neutralization by a uniform background of hot ions, and (e) dust is weakly coupled due to strong Coulomb screening. Thus, the dusty plasma is essentially a weakly coupled, one-component plasma with screening in the high dust density limit. Molecular dynamics (MD) simulations verify these properties. The MD simulations are performed, using a recently proposed Hamiltonian formalism to study the dynamics of Yukawa particles carrying variable electric charge. A hydrodynamic model for describing the collective properties of Coulomb plasma and its characteristic acoustic mode called the "Coulomb acoustic mode" arising due to imperfect Coulomb screening is given. [ABSTRACT FROM AUTHOR]

Current study presents an experimental analysis of nucleate pool boiling on the GNP/Ni-TiO2 (GNP-graphene nano particle) nano-composite coated copper surfaces. In order to produce the microporous surfaces, a two-step electrodeposition process is used. This deposition results in the formation of a modified surface structure, and various surface morphological characteristics of this modified structure, like wettability, roughness and surface structure are studied. The results reveal an improvement in CHF (critical heat flux) and BHTC (boiling heat transfer coefficient) in case of GNP/Ni-TiO2 coated surfaces. The main elements influencing the improved heat transfer of the GNP/Ni-TiO2 nanocomposite coating are its increased wettability, roughness, and high thermal conductivity. The SNCCC (superhydrophilic nano-composite coated copper) surfaces have the maximum BHTC of 97.52 (kW/m²K) and CHF of 2043 (kW/m²), which are 93% and 88% higher than the base Cu surfaces respectively. Here, it is analysed how the performance of SNCCC surfaces are enhanced by the impact of different parameters, like the roughness of the surface and wettability. The bubble characteristics at the time of boiling is noticed using a high-speed camera, and several factors such as nucleation site density, bubble departure diameter, and bubble emission frequency are statistically studied for SNCCC surfaces. [ABSTRACT FROM AUTHOR]

Raghuram Kandimalla,1 Suvakanta Dash,2 Ashim Chandra Bhowal,3 Sanjeeb Kalita,1 Narayan Chandra Talukdar,1 Sarathi Kundu,3 Jibon Kotoky1,4 1Drug Discovery Lab, Institute of Advanced Study in Science and Technology, 2Girijananda Choudhury Institute of Pharmaceutical Sciences, 3Soft Nano Laboratory, Institute of Advanced Study in Science and Technology, 4National Institute of Pharmaceutical Education and Research, Guwahati, India Abstract: In this study, a glycogen–gold nanohybrid was fabricated to enhance the potency of a promising hepatoprotective agent silymarin (Sly) by improving its solubility and gut permeation. By utilizing a facile green chemistry approach, biogenic gold nanoparticles were synthesized from Annona reticulata leaf phytoconstituents in combination with Sly (SGNPs). Further, the SGNPs were aggregated in glycogen biopolymer to yield the therapeutic nanohybrids (GSGNPs). Transmission electron microscopy, UV–Vis spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy analysis confirmed the successful formation and conjugation of both SGNPs and GSGNPs. The fabricated nanohybrids showed significant protection against CCl4-induced hepatic injury in Wistar rats and maintained natural antioxidant (superoxide dismutase and catalase) levels. Animals treated with GSGNPs (10 mg/kg) and SGNPs (20 mg/kg) retained usual hepatic functions with routine levels of hepatobiliary enzymes (aspartate transferase, alanine transaminase, alkaline phosphatase, and lactate dehydrogenase) and inflammatory markers (interleukin-1β and tumor necrosis factor-α) with minimal lipid peroxidation, whereas those treated with 100 mg/kg of Sly showed the similar effect. These results were also supported by histopathology of the livers where pronounced hepatoprotection with normal hepatic physiology and negligible inflammatory infiltrate were observed. Significant higher plasma Cmax supported the enhanced bioavailability of Sly upon GSGNPs treatment compared to SGNPs and free Sly. Graphite furnace atomic absorption spectrophotometry analysis also substantiated the efficient delivery of GSGNPs over SGNPs. The fabricated therapeutic nanohybrids were also found to be biocompatible toward human erythrocytes and L929 mouse fibroblast cells. Overall, due to increased solubility, bioavailability and profuse gut absorption; GSGNPs demonstrated tenfold enhanced potency compared to free Sly. Keywords: silymarin, Annona reticulata, glycogen–gold, nanohybrid, potency, hepatoprotection

Sanjeeb Kalita,1 Banasmita Devi,1 Raghuram Kandimalla,1 Kaustav Kalyan Sharma,1 Arup Sharma,2 Kasturi Kalita,3 Amal Chandra Kataki,4 Jibon Kotoky1 1Institute of Advanced Study in Science and Technology (IASST), Division of Life Sciences, Paschim Boragaon, Garchuk, Guwahati, Assam, India; 2College of Veterinary Science, Assam Agriculture University, Khanapara, Guwahati, Assam, India; 3Hyat Hospital, Lalganesh, Guwahati, Assam, India; 4Dr B Borooah Cancer Institute, Guwahati, Assam, India Abstract: The emergence of methicillin-resistant Staphylococcus aureus (MRSA) infection has increased precipitously over the past several decades, with far-reaching health care and societal costs. MRSA infections in the context of burn wounds lead to invasive disease that could potentially cause mortality. Chloramphenicol is a well-known broad-spectrum bacteriostatic antibiotic that has been used since 1949, but due to its hydrophobicity, poor penetration in skin, fast degradation, and toxicity, its application has been hindered. Furthermore, it has been demonstrated that old antibiotics such as chloramphenicol remained active against a large number of currently prevalent resistant bacterial isolates due to their low-level use in the past. Recently, the novel nanoparticulate drug-delivery system has been used and reported to be exceptionally useful for topical therapeutics, due to its distinctive physical characteristics such as a high surface-to-volume ratio and minuscule size. It helps to achieve better hydrophilicity, bioavailability, and controlled delivery with enhanced therapeutic index, which has resulted in decreased toxicity levels compared to the crude drug. Here, we report a novel chloramphenicol loaded with poly(ε-caprolactone) (PCL)-pluronic composite nanoparticles (CAM-PCL-P NPs), physicochemical characterizations, and its bioactivity evaluation in a MRSA-infected burn-wound animal model. CAM-PCL-P NPs could encapsulate 98.3% of the drug in the nanoparticles and release 81% of the encapsulated drug over 36 days with a time to 50% drug release of 72 hours (51%). Nanoparticle suspensions maintained the initial properties with respect to size and encapsulation efficiency, even after 6 months of storage at 4°C and 25°C, respectively (P>0.05). Significant reduction in the level of toxicity was observed for CAM-PCL-P NPs compared with that of free drug as confirmed from hemolytic activity against human blood erythrocytes and cytotoxicity assay against an MCF-7 breast cancer cell line. In vitro antibacterial activities were performed by zone of inhibition, minimum inhibitory concentrations, minimum bacterial concentration, and time-kill assays, which showed that CAM-PCL-P NPs exhibited significantly enhanced anti-MRSA activity against ten clinical isolates of MRSA strains. The augmented activity of CAM-PCL-P NPs was further tested on a MRSA-infected burn-wound animal model and achieved quicker efficacy in MRSA clearance and improved the survival rate compared with free-chloramphenicol treatment. Thus, we propose CAM-PCL-P NPs as a promising novel antimicrobial candidate that may have a good potential for preclinical applications. Keywords: chloramphenicol, PCL-pluronic, nanoparticle, methicillin-resistant Staphylococcus aureus, anti-MRSA activity, burn-wound animal model

A graph consists of some points and lines called vertices and edges. It is a mathematical representation of a network in which edges represent the existence of a particular relation among the vertices. Automata is a five tuple consisting of a set of states, inputs, outputs, one transition function, and one output function between these three sets. In this paper, an attempt is made to study automata with the help of the properties of graphs. For two given automation, with the help of the operations, viz. addition, union, inter-section, complement, ring sum, product, and composition of graphs, another automaton is derived. The objective is to identify and analyze the automaton obtained. In the study, some connections are observed between various au-tomata produced as well as between the adjacency matrix of the graph, and outputs of the automaton. [ABSTRACT FROM AUTHOR]

Knowledge on entomophagy and culinary processing of edible insects has been found among the Bodo community as a part of tradition and culture, which was passed from one generation to another. The present study was aimed at finding the prevailing entomophagy and culinary processing of the insects among the Bodos of Chirang district of Assam. The study was done by interviewing people with semi-structured questionnaires. During discussion it was revealed that eating pupa of eri silkworm (Samia ricini) was the most common in their diet as rearing of S. ricini was common in Chirang district of Assam. Moreover, eating of giant water bug (Lethocerus indicus), field or burrowing crickets (Brachytrupes portentosus), and social wasp (Vespa magnifica) were found common in Chirang district. Along with the insects, a fresh water snail, Brotia costula and Pila globosa were also found to be practised by the community. The results in terms of culinary processing of insects and fresh water snails as practised by the Bodo community of Chirang district, Assam have been enlisted in this paper. [ABSTRACT FROM AUTHOR]

The present study was conducted on eighteen male Assam goats of age ranging from day 1/day old to 10 months divided into six post natal age groups viz. group-I (0-day), group-II (2 months), group-III (4 months), group-IV (6 months), group-V (8 months) and group-VI (10 months) consisting of three animals in each group. Tissue pieces were collected from three different regions of the testis viz., upper, middle and lower and subsequently fixed in Bouin's solution. All the tissues were processed for paraffin sections and stained for various stains for demonstration of various histochemical substances viz. McManus method for glycogen, Alcian Blue method at pH 1.0 for acid mucopolysaccaharides, Fuelgen reaction for nucleic acids and Mercuric Bromophenol Blue method for Protein. The connective tissue of the capsule and septula testis was weakly reactive to basic proteins in day-old kids (group-I) and moderately reactive in 2 months old kids (group-II). The nuclei of the spermatogenic cells more particularly of the primary spermatocytes showed a strong reaction for basic proteins which were probably due to their increased activity during meiotic phases of spermatogenesis at 4 to 8 months of age (groups-II to V). The basement membranes of the seminiferous tubules were strongly PAS reactive in dayold kids (group-I), moderate in 2 months old kids (group-II) and weak reaction was seen in the older goats, where as the Sustentacular or Sertoli cells showed a very weak reaction in all the age groups under study. The capsule and septula testes showed a faint reaction for nucleic acids in the male goats in all the age groups. The nuclei of various spermatogenic cells were Fuelgen positive and the intensity of reaction increased with the advancing age of the kids. The connective tissue of the capsule and septula testis showed faint reactions for acid mucopolysaccharides in all the age groups. The Leydig cells were also weakly reactive in the kids up to 2 months of age (group-II), but showed moderate reactions in older kids. [ABSTRACT FROM AUTHOR]