Publications by authors named "Miryana Raykovska"

Sinter-crystallization is a specific method of producing glass-ceramics that allows the manufacture of complexly shaped products, composites and solder. However, it usually is limited when the glass powders used are characterized by a high crystallization trend. This study proposes a new opportunity to improve the sinter-crystallization and demonstrates the benefits of microwave processing using diopside (CaMg(SiO)) glass-ceramics with an enhanced crystallinity of ~70%.

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Aim: To compare the efficiency of root canal filling removal from oval-shaped root canals with high-energy Er:YAG laser and additional instrumentation with a rotary Ni-Ti XP-Endo Finisher R system.

Materials And Methods: The study was accomplished on 12 freshly extracted single-rooted mandibular incisors with one straight oval-shaped root canal, shaped with XP-Endo Shaper 30/.04 and obturated by using the warm vertical condensation technique subjected to further endodontic orthograde retreatment.

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Background: During the course of a non-surgical orthograde endodontic retreatment, supplementary instrumentation is usually required for better removal of root canal filling material.

Aim: The aim of this study was to assess the effectiveness of XP-Endo Finisher R in endodontic retreatment of oval root canals.

Materials And Methods: The study was performed on extracted mandibular incisors preliminary cut at the cementoenamel junction.

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Streptomyces sp. strain SB9 was isolated from perm frost soil samples in Spitsbergen, Arctic Ocean; it grows in a temperature range between 4 degrees C and 28 degrees C. During the survey of biologically active metabolites biosynthesized by this strain, significant amounts of alpha,alpha-trehalose (1) and glycerol (2) were detected.

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Collagen-induced arthritis (CIA) is a widely accepted model of autoimmune disease with significant similarities to rheumatoid arthritis in humans. CIA is provoked in susceptible strains upon immunization of adult mice with native type-II collagen in complete Freund's adjuvant (CFA). Neonatal exposure to antigen is supposed to result in T cell clone deletion and induction of tolerance.

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A thermostable D-xylose-glucose isomerase was isolated from the thermophilic strain Streptomyces thermovulgaris 127, var. 7-86, as a result of mutagenic treatment by gamma-irradiation of the parent strain, by precipitation and sequential chromatographies on DEAE-Sephadex A50, TSK-gel, FPLC-Mono Q/HR, and Superose 12 columns. The N-terminal amino acid sequence and amino acid analysis shows 73-92% homology with xylose-glucose isomerases from other sources.

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