On the accuracy of approximation of a small celestial body motion using intermediate perturbed orbits calculated from two position vectors and three observations

We examine intermediate perturbed orbits proposed by the first author previously, defined from the two position vectors and three angular coordinates of a small celestial body. It is shown theoretically, that at a small reference time interval covering the measurements the approximation accuracy of real movements by these orbits corresponds approximately to the third order of osculation. The smaller reference interval of time, the better this correspondence. Laws of variation of the methodical errors in constructing intermediate orbits subject to the length of reference time interval are deduced. According to these laws, the convergence rate of the methods to the exact solution (upon reducing the reference interval of time) is higher by two orders of magnitude than in the case of conventional methods using the Keplerian unperturbed orbit. The considered orbits are among the most accurate in set of orbits of their class determined by the order of osculation. The theoretical results are validated by numerical examples

Numerical modelling of radiant energy extinction by water medium containing bubbles and particles of various natures

In the framework of the Mie theory, we developed a numerical model of weakly absorbing medium, containing particles having an arbitrary chemical composition. This model can be applied to the study of the extinction characteristics of the optical radiation by a water layer with gas bubbles or volume-shape particles. The results of the numerical experiment illustrate changes in optical properties of the water due to the presence of bubbles or solid particles. The work displays some calculations of the extinction efficiency factor, the extinction coefficient, and transmission function at visible wavelengths. The influences of concentration and sizes of gas bubbles on the extinction characteristics of optical radiation are illustrated. Features of the extinction of radiant energy are discussed as dependent on a size parameter and a complex index of refraction of scatterers

Laser light scattering (LLS) to observe plasma impact on the adhesion of micrometer-sized particles to a surface

Laser light scattering (LLS) method, combined with a long-distance microscope was utilized to detect micrometer-sized particles on a smooth substrate. LLS was capable to detect individual particle release, shrink, or fragmentation during exposure to a plasma or a gas jet. In-situ monitoring of hundreds of particles was carried out to investigate the effect of hydrogen plasma exposure on particle adhesion, morphology, and composition. LLS was calibrated with monodisperse melamine resin spheres with known sizes of 2.14 µm, 2.94 µm, and 5.26 µm in diameter. The lowest achievable noise level of approximately 3% was demonstrated for counting 5.26 µm spherical melamine particles. The accuracy for melamine particle size measurements ranged from 50% for 2.14 µm particles to 10% for 5.26 µm particles. This scatter was taken as the imprecision of the method. Size distribution for polydisperse particles with known refractive index was obtained by interpolating to an effective scattering cross-section of a sphere using Mie theory. While the Abbe diffraction limit was about 2 µm in our system, the detection limit for Si particles in LLS according to Mie approximation was assessed to about 3 µm, given the limitations of the laser flux, microscope resolution, camera noise, and particle composition. Additionally, the gradual changes in forward scattering cross-sections for Si particles during the exposure to the hydrogen plasma were consistent with Si etching reported in the literature.</p

Analysis of an Exact Solution of Problem of the Evaporative Convection (Review). Part II. Three-dimensional Flows

In the paper the review of exact solutions of the three-dimensional convection problems is presented. The solutions allow one to model the two-layer convective fluid flows with evaporation at the thermocapillary interface

Analysis of an Exact Solution of Problem of the Evaporative Convection (Review). Part I. Plane Case

Development of theory describing the convection under conditions of "liquid – gas" phase transition, is caused by the active experimental study of the convective phenomena accompanied by evaporation/condensation at interphase. Results of the analytical and numerical investigation of new nonstandard problems of heat and mass transfer in domains with free surfaces or interfaces allow one to evaluate the adequacy of new mathematical models and to derive new characteristic criteria. The obtained fundamental knowledge on physical mechanisms of the studied processes provides the basis of modification and improvement of the fluidic technologies using the evaporating liquids and gas-vapor mixtures as working media. In the paper the analysis of the exact solution of the convection equations, which gives a possibility to model the two-layer convective fluid flows with evaporation, is presented

Air-tightness evaluation in thoracic surgery with use of laser optical-acoustic spectroscopy

The simple and effective method of the leakage test in thoracic surgery using laser photo-acoustic leak detector «LaserGasTest» was suggested and tested in experiment on mongrels. Sulfur hexafluoride used for the work of leak detector is an inert and biologically harmless gas of the 4th class of danger and its concentration in medical ventilation apparatus does not exceed 5000 mg/m3 (0.077 %). The proposed technique provides real-time high-frequency determination of location and size of leakage

USE OF TITANIUM NIKELIDE IMPLANT AND FREE REVASCULARIZED FLAP FOR RECONSTRUCTION OF FENESTRATED TRACHEAL DEFECT (EXPERIMENTAL INVESTIGATION)

Reconstruction of fenestrated tracheal defect using free revascularized flap combined with titanium nikelide implant has been developed. The experimental study was performed on 8 mongrels, on which defect or tracheostomy was created. The tracheal defect reconstruction was completed using free fasciocutaneous inguinal flap. Efficacy of the method was tested using clinical, radiological, macro- and microscopic examination. It is ascertained, that the technique permits to reconstruct fenestrated tracheal defect with minimal injury of donor zone, to simplify and shorten the operation

NEW TECHNOLOGIES iN RECONSTRUCTIVE SURGERY OF INJURIES AND CICATRICIAL STENOSES OF TRACHEA

The results of treatment of 9 patients with mechanical injury of trachea and of 22 patients with cicatricial stenoses of trachea are presented, in this article. 18 patients had. staged, reconstructive and plastic operations at the cicatricial stenosis, 2 patients had. endoscopic recanalization of tracheal lumen and. 2 patients had. sleeve resection of trachea with, anastomosis. An. original medical complex including argon-plasmatic, cryosurgical and. lymphotropic technologies. In all cases we managed, to recover respiratory tract integrity and. to provide adequate breath through, natural respiratory tract

Reconstructive interventions in thoracic surgery using titanium nickelide implants

The original techniques of bronchus stump closure, modeling and disjunction of non-neoplastic tracheoesophageal fistula, replacement of postresectional defects of the trachea, pericardium, diaphragm and the thoracic wall using titanium nickelide implants have been developed and tested. It was ascertained that these methods were highly effective and simplified and standardized surgical procedures, provided anatomic and physiologic reconstruction of the injured area

Фенотипический профиль клеток моноцитарно-макрофагального ряда в зависимости от состояния респираторного эпителия

The mechanism of the relationship between pretumor changes in the bronchial respiratory epithelium and the risk of progression of non-small cell lung cancer (NSCLC) remains unclear. It has been suggested that the relationship between reactive changes in the bronchial mucosa and NSCLC progression may be caused by the functional status of monocytic-macrophage cells as important participants in infammation, which determines both the risk of premalignant changes in the epithelium and malignant progression. The purpose of the study was to investigate the phenotypic profle of peripheral blood monocytes and macrophages induced from monocytes in vitro depending on the state of respiratory epithelium in NSCLC patients. Material and Methods. The study included 39 patients with newly diagnosed NSCLC. Based on the morphological examination of small bronchi taken at the distance of 3–5 cm from the tumor, patients were divided into the following groups depending on the type of pretumor changes: no pretumor changes (n=6), isolated basal cell hyperplasia (BCH) (n=13), combination of BCH and squamous metaplasia (SM) (n=3), combination of unchanged epithelium and focal BCH (n=17). The phenotypic features of peripheral blood monocytes and in vitro-induced macrophages were assessed before treatment using fow cytometry. Results. The state of the respiratory epithelium in NSCLC patients prior to the start of anticancer treatment was associated with the phenotypic features of peripheral blood monocytes, but not with the profle of macrophages induced from them. Distortion of the response of induced macrophages to the polarizing stimuli was observed in NSCLC patients: the cultured cells responded to both M1 and M2 inducers (LPS and IL-4, respectively) with a phenotype shift to M2, while the CD206 marker expression varied depending on the presence and type of pretumor changes. Conclusion. The phenotypic profle of peripheral blood monocytes was associated with the state of the respiratory epithelium in NSCLC patients before anti-tumor treatment, but not with the phenotypic features of induced macrophages.Механизм взаимосвязи предопухолевых изменений в респираторном эпителии бронхов с риском прогрессирования немелкоклеточного рака легкого (НМРЛ) остается неясным. Предполагается, что связь между реактивными изменениями в слизистой бронхов и прогрессированием НМРЛ может быть обусловлена функциональным статусом клеток моноцитарно-макрофагальной линии, являющихся важными участниками процессов воспаления, которое определяет как риск предопухолевых изменений в эпителии, так и прогрессирование злокачественного новообразования. Цель исследования – изучение фенотипического профиля моноцитов периферической крови и макрофагов, индуцированных из моноцитов in vitro, в зависимости от состояния респираторного эпителия у больных НМРЛ. Материал и методы. В исследование включено 39 больных с впервые диагностированным НМРЛ. На основании результатов морфологического исследования мелких бронхов, взятых на расстоянии 3–5 см от опухоли, в зависимости от варианта предопухолевых изменений больные были разделены на следующие группы: отсутствие предопухолевых изменений (n=6), изолированная базальноклеточная гиперплазия (БКГ) (n=13), сочетание БКГ и плоскоклеточной метаплазии (ПМ) (n=3), сочетание неизмененного эпителия и очаговой БКГ (n=17). Оценка фенотипических особенностей моноцитов периферической крови и индуцированных in vitro макрофагов проводилась до начала противоопухолевого лечения больных методом проточной цитометрии. Результаты. Состояние респираторного эпителия у больных НМРЛ до начала противоопухолевого лечения ассоциировано с фенотипическими особенностями моноцитов периферической крови, но не с профилем индуцированных из них макрофагов. У больных НМРЛ отмечено искажение ответа индуцированных макрофагов на поляризующие стимулы: как на М1-, так и на М2-индукторы (LPS и IL-4, соответственно) культивируемые клетки отвечали сдвигом фенотипа в М2-сторону, при этом экспрессия маркера CD206 варьировала в некотором диапазоне в зависимости от наличия и варианта предопухолевых изменений. Заключение. Фенотипический профиль моноцитов периферической крови ассоциирован с состоянием респираторного эпителия у больных НМРЛ до начала противоопухолевого лечения, но не с фенотипическими особенностями индуцированных макрофагов.