Persistence probabilities in centered, stationary, Gaussian processes in discrete time

Lower bounds for persistence probabilities of stationary Gaussian processes in discrete time are obtained under various conditions on the spectral measure of the process. Examples are given to show that the persistence probability can decay faster than exponentially. It is shown that if the spectral measure is not singular, then the exponent in the persistence probability cannot grow faster than quadratically. An example that appears (from numerical evidence) to achieve this lower bound is presented.Comment: 9 pages; To appear in a special volume of the Indian Journal of Pure and Applied Mathematic

Sporadic Medullary Microcarcinoma in a Young Patient - A Rare Case

Sporadic medullary microcarcinoma of thyroid is a rare disease detected usually in 0.15% of all thyroid malignancy. We report a case of sporadic medullary microcarcinoma (MMC) of thyroid in a 24 year old male presenting as solitary thyroid nodule. There was no family history of medullary carcinoma of thyroid. Although medullary carcinoma in a familial setting have been reported, sporadic MMC is rare especially in a young patient

Studies on carbohydrate moieties of the glycoprotein, glucoamylase II of Aspergillus niger: nature of carbohydrate-peptide linkage and structure of oligosaccharides

Electrophoretically homogeneous type 1 (GP-C1 and GP-C2), type 2 (GP-C3a and GP-C3b,) and type 3 (GP-D1, and GP-D2) glycopeptides from Aspergillus niger glucoamylase II (Manjunath and Raghavendra Rao, preceding paper) were separately treated with alkaline borohydride. The (β-eliminated oligosaccharides were subjected to single and sequential digestion with specific glycosidases and the products analysed by gas liquid chromatography. The studies revealed that carbohydrate moieties were present as mannose, Man-Man-, and trisaccharide structures, namely, (a) GIc-Man-Man-, (b) Gal-Man-Man, (c) Man-Man-Man-, (d) GlcNAc-Man-Man-, and (e) Xyl-Man-Man. None of the glycopeptides contained all the trisaccharide structures (a) to (e). Type 1 glycopeptide contained structures (a), (b) and (c); type 2, (a) and (d) and type 3, (a), (b) and (e). The number of carbohydrate units (mono-, di-and trisaccharides) present in the major glycopeptides was determined and tentative structures for the glycopeptides proposed. Carbohydrate units appeared to occur in clusters of 4 to 7 in each glycopeptide, a structure unique to the carbohydrate moiety in Aspergillus niger glucoamylase. Based on carbohydrate analysis and yields of glycopeptide, the number of units of each type of glycopeptide present in glucoamylase II was tentatively calculated to give two of type Man:Glc:Gal = 12-15:l:l, one of type Man:Glc:GlcN = 10-l1:1:2 and one of type Man :GIc :Gal:Xyl = 4-8:0.1:0.5-0.8:0.3-1 glycopeptides

Comparative studies on glucoamylases from three fungal sources

Five commercial preparations of glucoamylases (three from Aspergillus niger, one each from Aspergillus foetidus and Aspergillus candidus) were purified by ultrafiltration, Sepharose-gel filtration and DEAE-sephadex chromatography. Two forms of the enzyme, namely glucoamylase I and glucoamylase II were obtained from the fungi except from one strain of A. Niger. All the enzymes appeared homogeneous by electrophoresis and ultracentrifugation. The specific activities varied between 85 and 142 units. The pH and temperature optima were between 4 and 5, and 60°C respectively. The molecular weight as determined by the sodium dodecyl sulphate-polyacrylamide gel electrophoresis ranged from 75,000 to 79,000 for glucoamylase I and 60,000 to 72,000 for glucoamylase II. Only A. niger glucoamylases contained phenylalanine at the N-terminal end. The amino acid composition of the enzymes was generally similar. However, A. niger and A. foetidus glucoamylases, in contrast to A. candidus enzymes, contained greater percentage of acidic than of basic amino acids. The enzymes contained 15 to 30% carbohydrate and 49 to 57 residues of monosaccharides per mol. A. niger enzymes contained mannose, glucose, galactose, xylose and glucosamine but the A. candidus enzyme lacked xylose and glucose and only xylose was absent in A, foetidus enzymes. Majority of the carbohydrate moieties were O-glycosidically linked through mannose to the hydroxyl groups of seline and threonine of the polypeptide chain

Studies on carbohydrate moieties of Aspergillus niger glucoamylase. II: Isolation, purification and characterization of glycopeptides

Six glycopeptide fractions namely GP-C1, GP-C2, GP-C3a, GP-C3b, GP-D, and GP-D2 were isolated after exhaustive digestion of glucoamylase II (Glucozyme) from Aspergillus niger with pronase. They were purified using gel-filtration. high-voltage paper electrophoresis and ion-exchange chromatography on Dowex-50 and Dowex-1. They appeared homogeneous on electrophoresis under different conditions of pHs. The molecular weights ranged from 1600 and 4000 for these glycopeptides. Ally of them contained serine at the N-terminal end. Serine and threonine were the major amino acids with glycine, alanine, proline and tryosine present as minor constituents. Carbohydrate analysis revealed the presence of different sugars. Based on this, the glycopeptides were grouped into three types: (1) GP-C1 and GP-C2 containing mannose, glucose and galactose; (2) GP-C3a, and GP-C3b,containing mannose glucose and glucosamine; and (3) GP-D1 and GP-D2, containing mannose. glucose, galactose and xylose. Most sugar constituents in each glycopeptide occured in non-integral ratios implying a microheterogeneity of the carbohydrate moiety in Aspergillus niger glucoamylase II

Development of UVM based Reusabe Verification Environment for SHA-3 Cryptographic Core

In this work, an industry standard methodology for ASIC verification domain, SystemVerilog (SV) with Universal Verification Methodology (UVM) is introduced with its features and application to Keccak SHA-3 Cryptographic Core. The ASIC verification flow for SHA-3 core is followed with creation of UVM based verification environment. By application of UVM on the core, horizontal and vertical re-use can be achieved in standard projects. Proposed verification environment uses OOPs concepts from SV UVM to develop layered testbench. In this approach initial learning curve is slow, considering overhead to learn new verification methodology. But, once full fledge working environment is created, re-usability feature from SV UVM can be achieved with less amount of time. Also coverage results give effectiveness of the proposed verification environment. DOI: 10.17762/ijritcc2321-8169.15057

Formulation and in-vitro characterization of erythromycin ocular inserts

Erythromycin has antibacterial activity and especially useful in the treatment of superficial infections involving conjunctivitis and/or cornea caused by organisms. Sustained drug therapies have more advantages than conventional. In the present study, an attempt was made to formulate sustained drug delivery system for Erythromycin in matrix type the formulations for Erythromycin containing 10%, 12%, and 14% w/v of Gelatin & Hydroxy propyl methylcellulose, and 14% , 16%, and 18% w/v for Ethyl cellulose were prepared by solvent casting method and evaluated for their average weight variation, thickness, drug content, in-vitro drug release and stability studies. An increase in average weight and thickness is due to an increase in polymer concentration. IR spectral studies were performed to confirm the interaction of drug with excipients. IR spectrum revealed that there is no incompatibility and no drug-polymer interactions. In vitro drug release studies were performed by vial method. Gelatin F09, HPMC F15 and EC F21 exhibited maximum average weight 16.66 ± 0.02, 10.81 ± 0.01 & 21.40 ± 0.01 mg respectively and thickness of 0.29 ± 0.01, 0.33± 0.06 and 0.43± 0.02mm respectively. The drug content was found to be 94.48, 92.87 & 90.26% respectively. The in-vitro drug release studies showed that increase in polymer content decreases the drug release from ocular inserts. Formulations containing 16 % and 18% w/v of EC showed sustained and almost complete drug release and dissolved 86.99% and 85.00 % over 14hours period was selected as an ideal formulation. The dissolution data of above formulation were subjected to first order, Higuchi’s and peppa’s equations. The linearity and slope indicates that the release of erythromycin from the films might have followed Peppa’s double log plot and non Fickian characteristics. Drug release from the ocular insert by diffusion controlled mechanism. Stability studies conducted for F20 formulation. The formulation showed satisfactory physical stability at 25oC and 40oC at 60% and 75% RH respectively. The physical appearance had not changed considerably. It can be concluded that formulation containing EC 18 % w/v has achieved the objectives of increased contact time, prolonged release, decreased frequency of administration and thus may improve the patient compliance