Experimental Research of the Diffraction and Vavilov-Cherenkov Radiation Generation in a Teflon Target

Geometry of Vavilov-Cherekov (VChR) radiation when an electron moves close to a dielectric target is in analogy to diffraction radiation (DR) geometry. In this case we may expect DR generation from the upstream face of the target besides that VChR. The joint observation of these booth types of radiation is very interesting from the pseudo-photon viewpoint, which is applicable for relativistic electrons. Unexpected results obtained in our experiment insist on reflection about nature both DR and VChR. The experiment was performed on the relativistic electron beam of the microtron of Tomsk Polytechnic University.Comment: This article will be published in Journal of Physic

Formation of Galactic Systems in Light of the Magnesium Abundance in Field Stars: The Thin Disk

We analyze the relations between the relative magnesium abundances in stars and their metallicities, Galactic orbital elements, and ages. The relative magnesium abundances in metal-poor ([Fe/H] < -0.4) thin-disk stars have been found to systematically decrease with increasing stellar orbital radii in such a way that magnesium over abundances ([Mg/Fe]>0.2 dex) are essentially observed only in the stars whose orbits lie almost entirely within the solar circle. At the same time, the range of metallicities in magnesium-poor stars is displaced from (-0.5<[Fe/H]<+0.3 dex) to (-0.7<[Fe/H]<+0.2 dex) as their orbital radii increase. This behavior suggests that, first, the star formation rate decreases with increasing Galactocentric distance and, second, there was no star formation for some time outside the solar circle while this process was continuous within the solar circle. The decrease in the star formation rate with increasing Galactocentric distance is responsible for the existence of a negative radial metallicity gradient (grad_{R}[Fe/H]=(-0.05 \pm 0.01) kpc^{-1}) in the disk, which shows a tendency to increase with decreasing age. At the same time the relative magnesium abundance exhibits no radial gradient. We have confirmed the existence of a steep negative vertical metallicity gradient (grad_Z [Fe/H]=(-0.29 \pm 0.06) kpc^{-1}) and detected a significant positive vertical gradient in relative magnesium abundance (grad_Z [Mg/Fe]=(0.13 \pm 0.02) kpc^{-1}); both gradients increase appreciably in absolute value with decreasing age. We have found that there is not only an age-metallicity relation, but also an age-magnesium abundance relation in the thin disk.Comment: accepted 2006, Astronomy Letters, Vol. 32 No. 6, P.376-392, 14 pages, 10 figure

Hemozoin "knobs" in Opisthorchis felineus infected liver

Background Hemozoin is the pigment produced by some blood-feeding parasites. It demonstrates high diagnostic and therapeutic potential. In this work the formation of co-called hemozoin “knobs” – the bile duct ectasia filled up by hemozoin pigment - in Opisthorhis felineus infected hamster liver has been observed. Methods The O. felineus infected liver was examined by histological analysis and magnetic resonance imaging (MRI). The pigment hemozoin was identified by Fourier transform infrared spectroscopy and high resolution electrospray ionization mass spectrometry analysis. Hemozoin crystals were characterised by high resolution transmission electron microscopy. Results Hemozoin crystals produced by O. felineus have average length 403 nm and the length-to-width ratio equals 2.0. The regurgitation of hemozoin from parasitic fluke during infection leads to formation of bile duct ectasia. The active release of hemozoin from O. felineus during in vitro incubation has also been evidenced. It has been shown that the hemozoin knobs can be detected by magnetic resonance imaging. Conclusions In the paper for the first time the characterisation of hemozoin pigment extracted from liver fluke O. felineus has been conducted. The role of hemozoin in the modification of immune response by opisthorchiasis is assumed

Ингаляции ультрамалых доз алкилирующих препаратов в лечении бронхиальной астмы

The treatment of severe steroid-dependent asthma is a very serious problem. Our aim was to work out a new method of asthma treatment with inhalations of ultra-low (non-cytotoxic) doses of an alkylating drug (Melphalan) and to investigate its efficacy and tolerability.Forty-two patients with moderate and severe asthma, enrolled into a randomized, double-blind, placebo-controlled trial, were divided into two groups: 21 patients from the Melphalan-treated group (MTG) were treated with the standard therapy plus 5 daily inhalations of 0.1 mg of Melphalan, while the control group (CG) patients (21 persons) were treated with the standard therapy plus placebo inhalations. Spirometric, biochemical, hematological and immunological data were obtained before and 10 days after the treatment. Fiberoptic bronchoscopy with further investigation of bronchial mucosa biopsies was performed in 33 of 42 patients. There were no adverse events during the study. No patient dropped out of this study. An exertion tolerance increased and exacerbation severity and frequency of p2-agonist inhalations markedly reduced in MTG. A positive dynamics of lung ventilation parameters (p&lt;0.05) and of the exertion tolerance was revealed in MTG, while changes in the CG were unreliable. In 60% of MTG patients histo-ultrastructural signs of bronchial epithelium regeneration were revealed.In conclusion, our data suggest that combined therapy with inhalation of ultra-low doses of Melphalan is a safe and effective method of asthma treatment and needs further investigations.Лечение тяжелой бронхиальной астмы (БА) в настоящее время является серьезной проблемой. Целью исследования является разработка нового метода лечения БА ультранизкими (не цитотоксическими) дозами алкилирующего препарата мелфалана и оценка его эффективности и безопасности.В одноцентровом рандомизированном двойном слепом исследовании участвовали 42 пациента с БА среднетяжелой и тяжелой степени. Пациентам контрольной группы (21 человек) проводилось стандартное общепринятое лечение с дополнительными ежедневными ингаляциями плацебо. Пациентам основной группы (21 человек), помимо стандартной терапии, проводились ежедневные ингаляции 0,1 мг мелфалана в течение 5 дней. Всем больным до и через 10 дней после лечения выполняли спирометрические, биохимические, гематологические и иммунологические исследования. У 33 из 42 пациентов проведены фибробронхоскопии с последующим гистоультраструктурным исследованием бронхобиоптатов. Побочных реакций на ингаляции ультранизких доз мелфалана не было отмечено. Ни один пациент не выбыл из исследования. Толерантность к физической нагрузке увеличилась, а частота использования р2-агонистов и тяжесть приступов БА в основной группе значительно снизились (р&lt;0,05). Позитивные изменения показателей функции внешнего дыхания также были более выражены у пациентов основной группы. Отмечена достоверная положительная динамика показателей клеточного и фагоцитарного звеньев иммунитета у пациентов основной группы, в то время как изменения аналогичных параметров в контрольной группе были незначимы. У 60% пациентов основной группы после лечения отмечены гистоультраструктурные признаки регенерации эпителия.Полученные данные показали, что ингаляционная терапия БА ультранизкими дозами мелфалана является безопасным и эффективным методом лечения данного заболевания; требуются дальнейшие разработки в этом направлении

Газообмен и общий метаболизм у больных инсулинзависимым сахарным диабетом, осложненным кетоацидозом

Gas exchange and basal metabolism were investigated in young insulin-dependent diabetic patients with ketoacidosis. Fourteen patients were enrolled in this study. The energy expenditure and fat and keton utilization increased, the respiratory exchange ratio VC02/V02 reduced in these patients. The hypoxemia was not revealed. The lung hyperinflation and a reduction of single breath carbon monoxide diffusing capacity transfer factor were also registered. A pathogenic role of these disturbances is discussed in the article.У 14 молодых пациентов с впервые выявленным инсулинзависимым сахарным диабетом, осложненньм декомпенсированньм кетоацидозом, изучались состояние систем газотранспорта, основного обмена и утилизации метаболических субстратов. Выявлены повышение расходования энергии со снижением отношения респираторного обмена, отсутствие гипоксемии, резкое возрастание утилизации жиров и кетонов. Анализ механики внешнего дыхания и диффузионной способности позволил зафиксировать гиперинфляцию легких и снижение фактора переноса в режиме однократной задержки дыхания. В работе обсуждается патогенетическая роль выявленных нарушений респираторной системы

THE EFFECT OF SYNTHESIS CONDITIONS Ce:YAG CERAMICS ON LUMINESCENT AND OPTICAL PROPERTIES

In this conference paper, we report on the dependence luminescent and optical properties from the synthesis conditions of transparent 0.1 at.% Се:YAG and 1 аt.% Се:YAG ceramics. Transparent 2 mm thick samples with optical transmittance from 58 to 82% at a wavelength of 600 nm were obtained