61 research outputs found

    Kinetics of Acid-catalysed Hydrolysis of Hexanohydroxamic Acid

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    1086-108

    Gray Image Colorization using Thepade’s Transform Error Vector Rotation With Cosine, Walsh, Haar Transforms and various Similarity Measures

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    The paper presents various gray image colorization methods based on vector quantization for performing automatic colorization. To colorize gray target image by extracting color pixels from source color image, Thepade’s Transform Error Vector Rotation vector quantization methods such as Thepade’s Cosine Error Vector Rotation (TCEVR), Thepade’s Walsh Error Vector Rotation (TWEVR) and Thepade’s Haar Error Vector Rotation (THEVR) are used along with varied similarity measures. The quality of colorization of gray image is subjective to the source color image and target gray image (to be colored). Here the image test bed of 25 images is used to recolor the gray equivalent of the original color images for qualitative performance comparison of proposed colorization methods with help of PSNR between original color and recolored images. Colorization is performed using diverse similarity measures which belong to different families. These nine similarity measures are used for mapping gray image pixels with relatively corresponding multichorme image pixels. When these similarity measures are assessed for their comparison for colorizing the target gray image, it is observed that Chebychev outruns all other similarity measures and the worst performance is consistently given by Jaccard and Hamming distances. Among all the considered colorization methods Thepade’s Haar Error Vector Rotation is much suitable algorithm for performing gray image colorization. DOI: 10.17762/ijritcc2321-8169.150516

    Synthesis and evaluation of analgesic, anti-asthmatic activity of (E)-1-(8-hydroxyquinolin-7-yl)-3-phenylprop-2-en-1 ones

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    Abstract Seventeen (E)-1-(8-hydroxyquinolin-7-yl)-3-phenylprop-2-en-1 one derivatives were synthesized via aldol condensation of substituted benzaldehydes with quinoline chalcones starting from 8-hydroxy quinoline. Molecular docking studies were performed on COX-2 protein for analgesic activity and PDE 4 enzyme for anti-asthmatic activity. Docking studies for analgesic activity reveal that the compounds 2 , 4 , 12 , 14 , and 15 showed significant interaction in terms of hydrogen bonding, hydrophobic attachment and van der Waal interaction with COX-2. The docking studies and pharmacological screening indicate that substitution of hydroxyl and conjugated ketone groups on the aldehyde ring and the quinoline ring accelerates analgesia with better binding to active site. Eddy's hot plate method was used to evaluate analgesic activity of the synthesized compounds. Compounds showed a substantial increase in reaction time when compared with standard pentazocin. Compounds 2 , 4 , 7 , 9 and 13 showed significant binding interactions with PDE 4 enzyme and hence were selected for evaluation of anti-asthmatic activity using the goat tracheal chain method. Studies reveal that substitution of the methoxy group at 4th & 5th positions for compounds 2 , 4 & 7 leads to significant percentage inhibition of histamine induced contraction. The synthesized compounds are thus found to be potent as analgesic and anti-asthmatic agents

    DAF-16 and Δ9 Desaturase Genes Promote Cold Tolerance in Long-Lived Caenorhabditis elegans age-1 Mutants

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    In Caenorhabditis elegans, mutants of the conserved insulin/IGF-1 signalling (IIS) pathway are long-lived and stress resistant due to the altered expression of DAF-16 target genes such as those involved in cellular defence and metabolism. The three Δ9 desaturase genes, fat-5, fat-6 and fat-7, are included amongst these DAF-16 targets, and it is well established that Δ9 desaturase enzymes play an important role in survival at low temperatures. However, no assessment of cold tolerance has previously been reported for IIS mutants. We demonstrate that long-lived age-1(hx546) mutants are remarkably resilient to low temperature stress relative to wild type worms, and that this is dependent upon daf-16. We also show that cold tolerance following direct transfer to low temperatures is increased in wild type worms during the facultative, daf-16 dependent, dauer stage. Although the cold tolerant phenotype of age-1(hx546) mutants is predominantly due to the Δ9 desaturase genes, additional transcriptional targets of DAF-16 are also involved. Surprisingly, survival of wild type adults following a rapid temperature decline is not dependent upon functional daf-16, and cellular distributions of a DAF-16::GFP fusion protein indicate that DAF-16 is not activated during low temperature stress. This suggests that cold-induced physiological defences are not specifically regulated by the IIS pathway and DAF-16, but expression of DAF-16 target genes in IIS mutants and dauers is sufficient to promote cross tolerance to low temperatures in addition to other forms of stress

    Study Of Grooves Profile And Performance Of Hydrodynamic Bearing

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    A growing interest is given to the textured hydrodynamic lubricated contacts. The use of textured surfaces with different shapes of micro cavities (textures) and at different locations of the texture zone can be an effective approach to improve the performance of bearings. The present study examines the texture location influence on the hydrodynamic journal bearing performance. A numerical modeling is used to analyse the cylindrical texture shape effect on the characteristics of a hydrodynamic journal bearing. The theoretical results show that the most important characteristics can be improved through an appropriate arrangement of the textured area on the contact surface. Tribology is a science that covers the study of friction, wear, lubrication, and contact mechanics. It permits to understand the surface interactions and to propose solutions for essential problems. The expanding range of tribological applications, habitually from industrial machinery to microscopic applications recently, has revived the importance and interest in this field. The hydrodynamic bearings are frequently used in wide range of applications and mechanisms since long

    Flame retardant effect of nano fillers on polydimethylsiloxane composites

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    Polydimethylsiloxane has exceptional fire retardancy characteristics, which make it a popular polymer in flame retardancy applications. Flame retardancy of polydimethylsiloxane with different nano fillers was studied. Polydimethylsiloxane composite fire property varies because of the shape, size, density, and chemical nature of nano fillers. In house made carbon and bismuth oxide nano fillers were used in polydimethylsiloxane composite. Carbon from biochar (carbonised bamboo) and a carbon by-product (carbon soot) were selected. For comparative study of nano fillers, standard commercial multiwall carbon nano tubes (functionalised, graphitised and pristine) as nano fillers were selected. Nano fillers in polydimethylsiloxane positively affects their fire retardant properties such as total smoke release, peak heat release rate, and time to ignition. Charring and surface ceramization are the main reasons for such improvement. Nano fillers in polydimethylsiloxane may affect the thermal mobility of polymer chains, which can directly affect the time to ignition. The study concludes that the addition of pristine multiwall carbon nano tubes and bismuth oxide nano particles as filler in polydimethylsiloxane composite improves the fire retardant property
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