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Horizontal pressure gradient and Soret effects on the onset of thermosolutal porous convection
No full textThe intricacies of a constant horizontal pressure gradient on the onset of Soret-driven thermosolutal porous convection have been investigated. The resulting generalized eigenvalue problem is solved numerically using the Galerkin method and also the condition for the onset is obtained in a closed-form using a single-term Galerkin method with trigonometric trial function. The results obtained from both methods are found to be in good agreement. The effect of increasing horizontal pressure gradient, Lewis number, Soret parameter, and the Vadasz number is to hasten, while the increase in the solute Darcy–Rayleigh number is to delay the onset of oscillatory convection. The presence of the horizontal pressure gradient is found to decrease the threshold value of solute Darcy–Rayleigh number beyond which the instability sets in as oscillatory. Moreover, the horizontal pressure gradient imparts a conflicting behavior on the critical wave number and critical frequency of oscillations. The numerical results attained under the limiting cases are shown to be in excellent agreement with the published ones
Evaluation of Photoswitching Properties for Hockey Stick-Shaped Mesogens Bearing Azo Benzene Moieties
No full textIn this paper, we report the photoresponsive behavior of hockey stick-shaped mesogens bearing azo wing with different terminal alkoxy chains at one terminal end. Except for the compound E16, which exhibits SmC along with nematic phase, all other mentioned compounds exhibit nematic phase alone. Influence of chain length on the photophysical properties were investigated using UV-Vis spectroscopy. It is observed here that influence of chain length is negligible on thermal back relaxation time. Spectroscopic investigation with variable intensities of UV light studies reveals that reverse cis-trans isomerization process was inversely proportional to the intensity of illuminated light. The present study also reveals that the structure-property relationship plays a dominant role on shape anisotropic structures. A spectroscopic study of the solid sample using guest-host mixture was also carried out and the compilation of results forecast these mesogens as ideal candidates for optical storage devices
Minimal Block Knight’s Tour and Edge with LSB Pixel Replacement Based Encrypted Image Steganography
No full textThe data security of an information is predominant in the digital world and gaining lot of importance. Cryptography and steganography are widely used in providing security to an information. In the proposed algorithm, the image encryption and steganography are performed using Knight’s move in the game of chess called Knight’s Tour Algorithm. Minimum block or square required for a knight’s tour to reach all the squares is 5× 5 block. The 5× 5 blocks’ pattern generated is used for image encryption. The encrypted image is then embedded into another image and block shuffling is performed to obtain a crypto-stego image. Proposed algorithm is robust and provides high data security with a good PSNR and SSIM
Logistic and Tent Map Encrypted Image Steganography in Transformation Domain using DWT-LSB Technique
No full textThe data confidentiality in an image is predominant in digital-world and outstretching the importance. Steganography and Cryptography are generally used for securing information. The security level is enhanced by encrypting the secret image using dual chaotic system models to generate random encryption sequences using Logistic and Tent map in proposed algorithm. The encrypted image is inserted into another image in transformation domain using DWT-LSB steganography techniques. Proposed method is robust and providing high information security with a good SSIM and PSNR for encryption process and embedding process respectively
Genome-scale protein interaction network construction and topology analysis of functional hypothetical proteins in Helicobacter pylori divulges novel therapeutic targets
No full textThe emergence and spread of multi-drug resistance among Helicobacter pylori (H. pylori) strain raise more stakes for genetic research for discovering new drugs. The quantity of uncharacterized hypothetical proteins in the genome may provide an opportunity to explore their property and promulgation could act as a platform for designing the drugs, making them an intriguing genetic target. In this context, the present study aims to identify the key hypothetical proteins (HPs) and their biological regulatory processes in H. pylori. This investigation could provide a foundation to establish the molecular connectivity among the pathways using topological analysis of the protein interaction networks (PINs). The giant network derived from the extended network has 374 nodes connected via 925 edges. A total of 43 proteins with high betweenness centrality (BC), 54 proteins with a large degree, and 23 proteins with high BC and large degrees have been identified. HP 1479, HP 0056, HP 1481, HP 1021, HP 0043, HP 1019, gmd, flgA, HP 0472, HP 1486, HP 1478, and HP 1473 are categorized as hub nodes because they have a higher number of direct connections and are potentially more important in understanding HP's molecular interactions. The pathway enrichment analysis of the network clusters revealed significant involvement of HPs in pathways such as flagellar assembly, bacterial chemotaxis and lipopolysaccharide biosynthesis. This comprehensive computational study revealed HP's functional role and its druggability characteristics, which could be useful in the development of drugs to combat H. pylori infections
Benchmark solution for the stability of plane Couette flow with net throughflow
No full textThis paper investigates the stability of an incompressible viscous fluid flow between relatively moving horizontal parallel plates in the presence of a uniform vertical throughflow. A linear stability analysis has been performed by employing the method of normal modes and the resulting stability equation is solved numerically using the Chebyshev collocation method. Contrary to the stability of plane Couette flow (PCF) to small disturbances for all values of the Reynolds number in the absence of vertical throughflow, it is found that PCF becomes unstable owing to the change in the sign of growth rate depending on the magnitude of throughflow. The critical Reynolds number triggering the instability is computed for different values of throughflow dependent Reynolds number and it is shown that throughflow instills both stabilizing and destabilizing effect on the base flow. It is seen that the direction of throughflow has no influence on the stability of fluid flow. A comparative study between plane Poiseuille flow and PCF has also been carried out and the similarities and differences are highlighted
Multi-applications of new trinuclear Zr-SMI complex
No full textWe report on the synthesis route and applications of new solid material Zirconium salicylate methylimidazole. Zirconium based complex was successfully synthesized by a cost-effective, simple stirring method on a hot water bath. The synthesized material arranged in layers with notable properties such as crystalline nature, highly homogeneous topology, and stable oxidation states at room temperature, and large surface area, and thermal stability. As-synthesized zirconium 3D H-bonded complex subjected to multiple applications since it has met desirable characteristics. Zr-SMI electrode has shown rare combination of pseudocapacitor-battery behavior. Supercapacity of 1165 mAhg−1 at 3 Ag−1 was achieved by the Zr-SMI electrode in basic electrolyte. Excellent electrochemical sensing response was found by the Zr-SMI electrode for an organic molecules such as Methylene blue (MB), and L-alanine analytes. In addition, Zr-SMI showed excellent catalytic property towards complete degradation of MB, Methyle orange (MO), and rhodium (RH) dyes. All these results implied the excellent electrochemical and catalytic behavior of Zr-SMI and proved as a promising material for multiple applications. © 2021 Elsevier B.V
Thrombin- and plasmin-like and platelet-aggregation-inducing activities of Plumeria alba L. latex: Action of cysteine protease
No full textEthnopharmacological relevance: In folk medicine, parts of Plumeria alba L. are used for the treatment of many diseases, with its latex being used for curing skin diseases and promoting wound healing. Aim of the study: This study aimed to study the role of P. alba L. latex in hemostasis and platelet aggregation. Materials and methods: The latex of P. alba L. was processed to remove waxes and enrich protein content, and the final extract was named Plumeria alba L. natant latex (PaNL). PaNL was analyzed for protease activity against casein. The type of protease in PaNL was identified by using protease inhibitors such as E−64, phenylmethylsulfonyl fluoride, ethylenediaminetetraacetic acid, and pepstatin A. Human fibrinogen, fibrin, and collagen types I and IV were subjected to hydrolysis with different concentrations of PaNL. The thrombin-like activity of PaNL was determined by analyzing its fibrinogen-clotting and procoagulant activities. The role of PaNL in platelet aggregation was also investigated. Its hemorrhagic and edema-inducing activities were evaluated in a mouse model. Phytochemical compounds were identified by gas chromatography–mass spectroscopy. Results: The findings of casein/gelatin zymography confirmed that PaNL possesses protease activity. The results of the protease inhibition study indicated the presence of a cysteine-type protease(s) in PaNL. PaNL hydrolyzed the subunits of fibrinogen, fibrin, and collagen types I and IV. Its fibrin-degradation activity indicated that PaNL possesses plasmin-like activity. PaNL induced clotting of citrated human plasma within 3 min of incubation in the absence of CaCl2, indicating the presence of thrombin-like activity, which was further confirmed by the results of the fibrinogen-clotting assay. PaNL induced platelet aggregation in the absence of agonists. There was no hemolytic activity. Mice injected with PaNL did not show edema/ hemorrhagic activity. Conclusion: PaNL possesses procoagulant, fibrino(geno)lytic, thrombin- and plasmin-like activities and induces platelet aggregation, which could explain its usage for wound treatment in folk medicine. © 2021 Elsevier B.V
Synthesis, Characterization, Antimicrobial Activity Screening, and Molecular Docking Study of Pyrimidine Carbonitrile Derivatives
Full text linkThe present work describes the synthesis of 4-amino-6-(2-benzylidenehydrazinyl)-pyrimidine-5-carbonitrile derivatives, 4-amino-6-[(2-phenylethyl)amino]pyrimidine-5-carbonitrile, and 4-amino-6-(piperidin-1-
yl)pyrimidine-5-carbonitrile. The compounds were characterized by FT-IR and 1H and 13C NMR spectroscopy
and mass spectrometry. All the compounds were evaluated for in vitro antimicrobial activity against different
bacterial and fungal strains. The minimum inhibitory concentrations (MICs) of all the compounds were validated.
4-Amino-6-[2-(3,4-dimethoxybenzylidene)hydrazinyl]pyrimidine-5-carbonitrile and 4-amino-6-(piperidin-1-yl)-
pyrimidine-5-carbonitrile, which have the lowest MIC values were selected for cell leakage analysis and bacterial growth curve study. It was found that both the compounds have potential to induce bacterial cell membrane
rupture and disintegration. Field emission scanning electron microscopic analysis confi rmed the effect of the
selected compounds on the morphology of both Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria.
The mechanism of interaction between the drug and the target protein of S. aureus and E. coli was studied by
molecular dockin