The Nature of Gamma-ray Bursts in the Framework of the Byuon Theory

Two models of gamma-ray bursts using the theory of byuons (TB) are considered. This theory describes a “life” of special unobservable discrete objects from which the surrounding space and the world of   ultimate particles are formed. Basic axioms and some conclusions of this theory are discussed. It is shown that basic problems with nature of gamma-rays bursts can be solved in the framework of this theory not only for bursts connected with supernova explosions but also for those without explosions

Two dimensional electron gas driven by strong alternating electric field

2D Fermi liquid driven by uniform alternating electric field at zero temperature may remain in quantum coherent non-equilibrium state. We develop a quasistatic approximation for strong and slow ac-fields and solve the problem of driven disordered 2D electron gas in high non-overlapping Landau levels. The broadening of Landau level has the Lorentz form and is inversely proportional to the amplitude of the ac-field. In the absence of electron-phonon interaction the electron distribution function is constant within the last Landau level and the diagonal dc-conductivity is zero. For weak electron-phonon interaction the dc-conductivity is anisotropic. A kinetic transition from the phonon cooling to the phonon heating is predicted.Comment: 8 pages, 1 figure REVTE

Age-related changes of the vitreous body

Innovative advances in recent years in the study of pathological changes of the posterior segment of the eye including the use of optical coherence tomography which is considered the gold standard for diagnosing vitreoretinal interface pathology, not only significantly expanded the idea of the most prevalent lesions of the structure of posterior eye segment but also discovered absolutely new aspects of their pathology. The review emphasizes the spreading understanding of vitreous body, its age-related changes in the pathology of the posterior eye segment. Two main interrelated processes occurring in the vitreous body - synchysis and syneresis, gradually increasing with age, are considered. Synchysis process begins at the early age and by the age of 70 reaches 50% of the volume of the vitreous body in 70% of the population. Parallelly, syneresis provides strength and plasticity of the entire vitreous volume due to collagen involved in formation of fibrillar frame. An important role in maintaining a stable and viscoelastic structure of the vitreous body, belonging to hyaluronic acid, is discussed, the level of which remains relatively stable at any age due to its constant synthesis. The accumulated data on the structure of age-related and pathological biodegradation of the vitreous body demonstrates inevitable progression of this process leading to age-related posterior vitreous detachment, which is a detachment of the posterior cortical layers of the vitreous body from subjacent retina. Posterior detachment under the influence of age-related changes in the vitreous body has certain stages - from incomplete juxtafoveolar detachment to complete posterior vitreous detachment with clinical retinal changes corresponding to each stage (idiopathic macular holes, lamellar macular tears, macular fibrosis, vitreomacular traction syndrome, myopic foveoschisis). Complete posterior vitreous detachment usually does not cause anatomical retinal disorders and any clinical forms of its diseases, thus, it can be considered as a natural favorable outcome

Role of N-acetyltransferase 2 gene polymorphism in the human pathology

Nowadays multiple heterogeneous chemicals affect the human body. They include drugs, household chemicals, dyes, food supplements and others. The human organism can modify, inactivate, and eliminate the chemicals by biotransformation enzymes. But it is well known that biotransformation can lead to toxification phenomenon. Individuals differ from each other by the rate of chemical modification that promotes accumulation of toxins and carcinogens in some patients. An N-acetyltransferase 2 enzyme participates in the aromatic amines second phase metabolism. This work reviews the acetyltransferase gene polymorphism possible role in diseases development including drug-induced organs damage.Gene of acetyltransferase has polymorphisms associated with two haplotypes of  fast and slow substrate acetylation. Gene alleles combine in three genotypes: fast, intermediate, and slow acetylators. Acetylation rate plays a significant role in side effects development during tuberculosis treatment and cancer pathogenesis. Recently, new data described the role of enzyme in development of non-infectious diseases in the human. Scientists consider that slow acetylation genotype in combination with high xenobiotic load result in accumulation of toxic substances able to damage cells.Therefore, acetyltransferase genotyping helps to reveal risk groups of cancer and non-infectious disease development and to prescribe more effective and safe doses of drugs