60 research outputs found

    Image Compression and Watermarking scheme using Scalar Quantization

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    This paper presents a new compression technique and image watermarking algorithm based on Contourlet Transform (CT). For image compression, an energy based quantization is used. Scalar quantization is explored for image watermarking. Double filter bank structure is used in CT. The Laplacian Pyramid (LP) is used to capture the point discontinuities, and then followed by a Directional Filter Bank (DFB) to link point discontinuities. The coefficients of down sampled low pass version of LP decomposed image are re-ordered in a pre-determined manner and prediction algorithm is used to reduce entropy (bits/pixel). In addition, the coefficients of CT are quantized based on the energy in the particular band. The superiority of proposed algorithm to JPEG is observed in terms of reduced blocking artifacts. The results are also compared with wavelet transform (WT). Superiority of CT to WT is observed when the image contains more contours. The watermark image is embedded in the low pass image of contourlet decomposition. The watermark can be extracted with minimum error. In terms of PSNR, the visual quality of the watermarked image is exceptional. The proposed algorithm is robust to many image attacks and suitable for copyright protection applications.Comment: 11 Pages, IJNGN Journal 201

    Lack of significant association of an insertion/deletion polymorphism in the angiotensin converting enzyme (ACE) gene with tropical calcific pancreatitis

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    BACKGROUND: The genetic basis of tropical calcific pancreatitis (TCP) is different and is explained by mutations in the pancreatic secretory trypsin inhibitor (SPINK1) gene. However, mutated SPINK1 does not account for the disease in all the patients, neither does it explain the phenotypic heterogeneity between TCP and fibro-calculous pancreatic diabetes (FCPD). Recent studies suggest a crucial role for pancreatic renin-angiotensin system during chronic hypoxia in acute pancreatitis and for angiotensin converting enzyme (ACE) inhibitors in reducing pancreatic fibrosis in experimental models. We investigated the association of ACE gene insertion/deletion (I/D) polymorphism in TCP patients using a case-control approach. Since SPINK1 mutations are proposed a modifier role, we also investigated its interaction with the ACE gene variant. METHODS: We analyzed the I/D polymorphism in the ACE gene (g.11417_11704del287) in 171 subjects comprising 91 TCP and 80 FCPD patients and compared the allelic and genotypic frequency in them with 99 healthy ethnically matched control subjects. RESULTS: We found 46% and 21% of TCP patients, 56% and 19.6% of FCPD patients and 54.5% and 19.2% of the healthy controls carrying the I/D and D/D genotypes respectively (P>0.05). No significant difference in the clinical picture was observed between patients with and without the del allele at the ACE in/del polymorphism in both categories. No association was observed with the presence or absence of N34S SPINK1 mutation in these patients. CONCLUSION: We conclude that the ACE insertion/deletion variant does not show any significant association with the pathogenesis, fibrosis and progression of tropical calcific pancreatitis and the fibro-calculous pancreatic diabetes

    Induction of vacuolar invertase inhibitor mRNA in potato tubers contributes to cold-induced sweetening resistance and includes spliced hybrid mRNA variants

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    Cold storage of tubers of potato (Solanum tuberosum L.) compromises tuber quality in many cultivars by the accumulation of hexose sugars in a process called cold-induced sweetening. This is caused by the breakdown of starch to sucrose, which is cleaved to glucose and fructose by vacuolar acid invertase. During processing of affected tubers, the high temperatures involved in baking and frying cause the Maillard reaction between reducing sugars and free amino acids, resulting in the accumulation of acrylamide. cDNA clones with deduced proteins homologous to known invertase inhibitors were isolated and the two most abundant forms, termed INH1 and INH2, were shown to possess apoplastic and vacuolar localization, respectively. The INH2 gene showed developmentally regulated alternative splicing, so, in addition to the INH2α transcript encoding the full-length protein, two hybrid mRNAs (INH2β*A and INH2β*B) that encoded deduced vacuolar invertase inhibitors with divergent C-termini were detected, the result of mRNA splicing of an upstream region of INH2 to a downstream region of INH1. Hybrid RNAs are common in animals, where they may add to the diversity of the proteome, but are rarely described in plants. During cold storage, INH2α and the hybrid INH2β mRNAs accumulated to higher abundance in cultivars resistant to cold-induced sweetening than in susceptible cultivars. Increased amounts of invertase inhibitor may contribute to the suppression of acid invertase activity and prevent cleavage of sucrose. Evidence for increased RNA splicing activity was detected in several resistant lines, a mechanism that in some circumstances may generate a range of proteins with additional functional capacity to aid adaptability

    Inhibition of Aspergillus flavus colonization and aflatoxin (AfB1) in peanut by methyleugenol

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    63-67Methyleugenol is naturally occurring substance in oils and fruits and in various foods as flavoring agent. Effect of this methyleugenol in inhibiting A. flavus colonization and aflatoxin production on peanut pods and kernels has been studied. Spray of methyleugenol (0.5 %) on peanut pods and kernels checked the colonization of A. flavus and aflatoxin synthesis. This chemical can be used as both prophylactic or post infection spray on peanut pods before storage. It is the first report on the inhibition of A.flavus by methyleugenol on peanut

    Hydrogenation of acetylenics by Pd-exchanged mesoporous materials

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    Pd/Si-K10 and Pd/MCM-41 were prepared by exchange in organic media of mesoporous Si modified K10 clay and Na-Al-MCM-41 and the efficiency of these catalysts versus microporous Pd/Y-zeolite is reported in the hydrogenation in the liquid phase of olefins, acetylenes and semi-hydrogenation of acetylenes

    L-selective dipeptide synthesis using novel thermophilic enzyme from Clostridium sp.

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    A novel, inexpensive, thermophilic protease-type enzyme isolated from Clostridium thermohydrosulfuricum was used for dipeptide synthesis. The enzyme showed broad substrate selectivity and enantioselectivity towards L-amino acids in peptide bond formation
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