Affine modifications and affine hypersurfaces with a very transitive automorphism group

We study a kind of modification of an affine domain which produces another affine domain. First appeared in passing in the basic paper of O. Zariski (1942), it was further considered by E.D. Davis (1967). The first named author applied its geometric counterpart to construct contractible smooth affine varieties non-isomorphic to Euclidean spaces. Here we provide certain conditions which guarantee preservation of the topology under a modification. As an application, we show that the group of biregular automorphisms of the affine hypersurface $X \subset C^{k+2}$ given by the equation $uv=p(x_1,...,x_k)$ where $p \in C[x_1,...,x_k],$ acts $m-$transitively on the smooth part reg$X$ of $X$ for any $m \in N.$ We present examples of such hypersurfaces diffeomorphic to Euclidean spaces.Comment: 39 Pages, LaTeX; a revised version with minor changes and correction

Локальное лечение острой эмпиемы плевры и пиопневмоторакса

A complex therapy of acute empyema and pyopneumothorax increases an efficacy of the pathogenic therapy and improves an outcome. It involves cryoplasma and anti-ensyme complex, plasmapheresis, correction of metabolic, coagulant and proteolytic activities of blood and focal (at the inflammation zone) phagocytes, intrapleural application of proteolytic inhibitors and activators depending on the phase of the inflammation.Применение комплексной терапии острых эмпием плевры и пиопневмоторакса с использованием криоплазменно-антиферментного комплекса, плазмафереза и плазмолейкафереза, коррекция метаболической, коагулянтной и протеолитической активности фагоцитов крови и очага воспаления, внутриплевральное введение ингибиторов и активаторов протеолиза в зависимости от фазы течения воспалительного процесса повышают эффективность патогенетического лечения и улучшают исходы заболевания

High-temperature characteristics of zone-melting recrystallized silicon-on-insulator MOSFETs

Abstract. The characteristics of enhancement-mode MOS transistors fabricated on zone-melting recrystallized (ZMR) silicon-on-insulator (SOI) films were systematically experimentally investigated in the temperature range 25300°C. The main temperature-dependent parameters (the threshold voltage, the channel mobility, subthreshold slope, off-state leakage currents) of ZMR SOI MOSFETs are described and compared with both theory and SIMOX devices. It is shown that high carrier mobilities and low off-state leakage currents can be obtained in thin-film ZMR SOI MOSFETs at elevated temperatures. At T = 300°C, far beyond the operating range of bulk silicon devices, the off-state leakage current in ZMR SOI MOSFETs with a 0.15 µm-thick silicon film was only 0.5 nA/µm (for V D = 3 V), that is 3 4 orders of magnitude lower than typical values in bulk Si devices. The presented results demonstrate that CMOS devices fabricated on sufficiently thin ZMR SOI films are well suited for high-temperature applications