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The paper reveals the procedure of calculation of velocity fields, flame temperature and changes in concentration of the components of combustion products on the basis of time and length of a turbulent flame of gas-burning devices. This method is used to justify the selection of burners for state-of-the-art furnaces of the Republican Unitary Enterprise (RUE) «Byelorussian Steel Mills».

Designing the antenna systems for space vehicles employing electrojet thrusters has to be based on a strict solution of the problem of electromagnetic wave diffraction on two bodies. Here, the problem of diffraction on two spherical surfaces is strictly solved in terms of the scalar field potentials. A method for the transformation of wave amplitudes upon a shift of the spherical coordinate system is proposed. The results of numerical calculations are presented.

The Fokker–Planck equation for the distribution function of the intensity of an individual component has been solved in the approximation of the Ornstein–Uhlenbeck process within the framework of the formalism of the method of polarization components. Based on this solution, we have constructed the distribution functions of the degree of lasing radiation polarization, analyzed experimental data for a certain geometry of laser pumping, and determined the values of the distribution parameters, including the loss coefficients for the polarization component.

A rigorous solution to the problem on the normal incidence of a plane electromagnetic wave on a linear layer of planar stratified cold plasma of a finite thickness is expressed in terms of the Airy functions. It is numerically shown that the electric field near the zero permittivity can substantially increase. The Ginzburg solution for a linear semi-infinite layer is improved.

The interaction of an electromagnetic wave with a plasma stream of a space vehicle electrojet thruster was studied within the framework of the plane-and spherical-layer solid dielectric models. The problem of electromagnetic compatibility of the space vehicle radio systems is significantly complicated by the predicted phenomenon, whereby a solution in the vicinity of a zero permittivity may qualitative change with small variations of the problem parameters. The proposed theory provides for an exact solution of the problem of electromagnetic wave diffraction on two bodies. The results of calculations are presented.

The aggregation stability of aqueous dispersions of the hydrated anatase and rutile samples in the neutral and alkaline pH regions is related to the electrostatic stabilization factor and is described in terms of the classical DLVO theory. The abnormally high stability of the dispersions with respect to 1 : 1 and 1 : 2 coagulating electrolytes, which is exhibited in the acidic pH region, is explained by the existence of well-developed gel layers at the particle surfaces. The specific role in the formation of such layers is played by the sulfate ions.

The hydrodynamics of a ventilated cavity with a negative cavitation number are studied experimentally. The pressure distributions in the closure region of the cavity, the “flow-pressure head” characteristics, and the cavitation number (or pressure coefficient) as a function of the gas-injection rate are measured. The two-phase flow pattern near the Taylor-unstable cavity boundary is investigated using spark photography and videophotography. The results are compared with the known theoretical and numerical data. It is shown that in the near-critical flow regime the basic mechanism of gas entrainment from the cavity is connected with the Rayleigh-Taylor instability. On this basis, the gas entrainment coefficient of the cavity is found to be proportional to the curvature of the cavity boundary and the square of the boundary length.

We describe here a new property of visual neurons: sensitivity to the magnitude and orientation of the brightness gradient vector in a test stimulus presented in the receptive field of the neuron. The brightness gradient test image was a spot (diameter 4°) on the dark background of the slide. Brightness changed linearly within the spot. The absolute value of the brightness gradient varied over the range 0.4–2.7 cd/m2/° in the direction of the brightness gradient. The integral brightness in the test spot containing the gradient image was identical for different values of the brightness gradient. The numbers of spikes in the on- and off-responses of on and off neurons in the lateral geniculate body of cats depended on the orientation of the brightness gradient vector in the test stimulus. The sensitivity of neurons to the orientation of the brightness gradient vector, K (the coefficient of sensitivity), was assessed as the normalized difference between the number of spikes in neuron responses in the preferred and non-preferred orientations of the brightness gradient vector in the neuron's receptive field. The mean sensitivity coefficient for 53 cells was 0.55 ± 0.20. A 6.7-fold decrease in the brightness gradient resulted in a 3.7-fold decrease in the coefficient of sensitivity (for the preferred direction of the orientation of the gradient vector); there was no change in the latent period of responses. The preferred orientation of the brightness gradient vector in the receptive fields of neurons coincided (to within ±22.5°) with the radial direction on the map of the field of vision in 45% of cases, and with the tangential direction in 26% of cells.

An exact solution to the problem of a plane wave propagation in a plane-stratified dielectric layer of arbitrary thickness is studied. An approach based on self-consistent finite differences is suggested, replacing the layer by a stack of homogeneous sublayers of variable thickness matched to the local behavior of the permittivity profile. For the region around zero permittivity, it is predicted that small perturbations of the physical parameters of the problem cause qualitative and quantitative changes in the solution. The conditions for the excitation of a surface wave are formulated. Computed data for the wave are presented.

Reviewed are the latest achievements in studying the information transfer mechanisms and the evolutionary significance of prebiotic RNA synthesis, the double helix structures most preferred in this respect, and the possible reasons for the prevalence of particular enantiomeric forms of nucleotides in template-directed synthesis.

Heterocyclic bases and phosphate groups involved in the DNA–methyltransferase SsoII (M · SsoII) interaction were identified in the regulatory DNA region localized within the promoter region of the SsoII restriction–modification genes by footprinting with the use of formic acid, hydrazine, dimethyl sulfate, and N-ethyl-N-nitrosourea as modifying agents. It has been established that the enzyme interacts with three guanines, one adenine, two thymines, and three phosphate groups of each strand of the DNA duplex. These heterocyclic bases and phosphate groups are disposed symmetrically within the 15-mer inverted repeat of the regulatory DNA region. It has been demonstrated by footprinting with dimethyl sulfate that the C7 atoms of guanines interacting with the enzyme are exposed to the DNA major groove. Two theoretical models were built describing the contacts in a complex between M · SsoII and the regulatory DNA region.

We developed a physicomathematical model to predict volcanic explosion-induced gasdynamic phenomena and the dynamics of the distribution of particles of ash and dust that precipitate onto the earth’s surface and that remain in the atmotsphere. We investigated the factors and processes that exert an influence on the transport of dust particles in the atmosphere. On the basis of the physicomathematical model developed, numerical simulation of volcanic explosions of specified power and space scale is done, and results on the dynamics of gasdynamic flows of air and the distribution of dust particles for different instants of time are analyzed.

The passage of a plane wave through an inhomogeneous flat insulator layer of arbitrary thickness without absorption is considered. A method is given for solving the problem in terms of elementary functions, which reduces the number of independent parameters of the layer. A similarity principle for layers having equivalent reflectivities is described. It is shown that the electric field intensity can increase to infinity near the critical point where ɛ=0.

The effect of active substrate on the process of liquid-phase reduction of para-nitrotoluene (P-NT) on a highly porous cellular palladium catalyst (HPCPC) is studied. The rate of the reducing reaction for 50% transformation of the initial nitric compound in the temperature range of 52 – 58°C is determined for the HPCPC using various oxides and their sulfatized forms as active substrate. It is shown that the highest velocity of P-NT hydration is reached using the HPCPC with an active substrate made of sulfatized ZrO2 and γ-Al2O3. The constants of reducing P-NT and the load of the nitric compound on the catalyst are calculated; the highest values are found in the HPCPC with a sulfatized ZrO2 substrate.

Equations of convection in a gas are analyzed and a computational algorithm that is efficient when the condition μgh/RT≪1 is satisfied for an arbitrary (fairly large) temperature drop is proposed. Calculations of convection occurring in steady nonuniform heating of walls are performed for axisymmetric argoncontaining volumes of different shape. Results of these calculations demonstrate the establishment of steady and periodic motions of the gas.

The population kinetics of the energy levels of atoms excited in a tube with an electron beam is studied. A method of separating the contributions made by direct electron impact and by secondary processes to the population of the levels considered is proposed.

To evaluate the potential of the color duplex scanning in revealing of the portal hypertension in patients with chronic pancreatitis.94 patients with chronic pancreatitis were investigated. In 61 patients (65%) pancreatitis was complicated by extrahepatic portal hypertension (EHPH) and 31 patients (35%) were without signs of rising of the portal pressure.Investigations in B-regime have shown that in patients with EHPH chronic calculous pancreatitis was revealed in 48%, development of pancreatic hypertension in 75%, increase of the pancreas head up to more than 40 mm in 58% of patients. We did not reveal statistically significant differences in pseudo-cysts in pancreas, extension of extrahepatic and intrahepatic ducts and infiltrative changes in parapancreatic cellular tissue in patients with and without EHPH. A development of EHPH in 31 (51%) patients was preconditioned by an extravasal compression of veins of portal system, combination of extravasal compression with thrombosis was found in 11 (18%) patients, in 12 (20%) patients thrombosis of the magistral veins of portal system was revealed and in 7 (11%) patients hemodynamics was not changed. Resections were found to be preferable operations for recovery of portal circulation. Increase and normalization of portal circulation found after transversal section of pancreas (Beger operation, pancreo-duodenal resection, distal resection of pancreas). A tendency to normalization of the blood flow was observed after the Frey operation.

The experimental investigation of the laws of friction at high relative speeds involves difficulties associated with ensuring that the experimental apparatus provides a sufficiently long slide path. In this paper an automated experimental apparatus is described. This makes it possible to study in a compact fashion the laws of fluid friction at speeds of approximately 150 m/sec under widely variable load and external pressure. The experimental relations for the friction moment coefficient for water in the laminar and turbulent regimes are compared with calculations made by the integral relations method of boundary layer theory. The results of series of experimental and theoretical studies of high-speed friction against ice in the developed fusion layer regime are presented. Questions of the effectiveness of using polymer additives to reduce friction at high speeds are considered. The experimental method described can be used to investigate friction problems involving pastes, emulsions, and other rheologically complex continuous media, in which under conditions of high velocity gradients (strain rates) qualitatively new effects are to be expected.

Numerical simulation of the dynamics of propagation and formation of the front of a nonstationary spherical heat wave in air is performed. The time dependence of the radiation of the front in the optical range of the spectrum is obtained. The existence of two phases in the propagation of a heat wave is established.

Numerical simulation of the flow of air originating as a result of volcanic eruption is carried out with the parameters corresponding to those figuring in the eruption of the Krakatau volcano in 1883 (with an energy of 100–1000 Mton of TNT equivalent). The results of the calculation are compared with the consequences of the disaster known from the literature.

The problem of the cooling of a spherical volume of air after departure of a shock wave in air of normal density is studied numerically. Based on the results obtained, a conclusion is made that no radiative cooling wave exists in a real atmosphere.

Investigation of time-of-flight spectra of excited krypton molecular ions observed under electron-beam bombardment of excitation tube electrodes is continued. Particular attention is focused on a study of the profile of the light signal produced in the dissociation of the molecular ions. An analysis of the light signal profile provides information on the processes involved in the formation and destruction of molecular ions. A model developed for these processes permitted calculation of the light signal profile. A comparison is made with experimental data on the spectral lines of krypton atoms and ions, whose excitation is caused by the destruction of the molecular ions.

15 patients with intraductal papillary-mucinous tumors (IPMT) of the pancreas were observed. Clinical manifestation corresponded with chronic pancreatitis. Ultrasound study, including endosonography, contrast-enhanced computer and magnetic resonance tomography were used in complex observation of the patients. Dilation of main or lateral pancreatic ducts, connection of tumor with pancreatic duct system and absence of septal calcinosis are typical signs in radiodiagnostics of IPMT. Visualization of parietal papillary proliferations and their contrast enhancement are undeniable signs f or neoplastic character of pancreatic duct dilation. Sensitivity of CT, MRТ and endoUS amounted accordingly 66, 83 and 88%. All patients were operated. Extent of operation was determined by morphological character, localization and size of the tumor (pylorus-preserving pancreaticoduodenal resection was carried out to 6 patients, distal resection including robot-assisted - to 7 patients, midline resection - to 1 patient, duodenum-preserving resection of head and body of pancreas - to 1 patient). Intraoperative urgent histologic study of pancreatic section was carried out by all means. Tumors with borderline degree of malignancy were detected in 4 cases.

Analyzing the commonest characteristics of early activation (EA) programs could objectively confirm the expediency of their wide introduction, by studying the commonest characteristics of EA as a means for improving anesthetic and resuscitative provision of surgery with extracorporeal circulation for coronary heart disease and postoperative rehabilitation.

The discovery of signal receptors of congenital immunity (signal PRR) not only provided a novel view of basic aspects of pathogenesis of chronic inflammatory diseases but also created a basis for the development of additional diagnostic criteria for these pathologies and new pharmaceuticals for their treatment. Reduced expression and function of PRR due to mutations/polymorphisms or epigenetic disturbances of regulation can be regarded as immunodeficient conditions manifest as severe infectious inflammatory diseases. In contrast, excessive expression and activation of PRR as a rule leads to chronic autoinflammatory, autoimmune, and atopic diseases involving adaptive immunity and aggression against own tissues and cells. Assessment of certain mutations in PRR genes, their expression and activation provides a powerful tool for in-depth diagnostics of inflammatory diseases. Simultaneously, new lines of immunostimulating and anti-inflammatory therapy are developed based on the knowledge of molecular physiology of PRR with the use of synthetic agonists and antagonists of signal PRR.

The aim of the study was to explore the possibilities of CT in evaluating resectability of pancreatic head adenocarcinoma, depending on the tumor.The results of CT and intraoperative findings in 62 patients with cancer of the head of the pancreas.It was shown that the tumor localized in caudal glands, had higher resectability when compared with tumors of the cranial localization at tumor sizes of 3-4 cm in size tumor less than 3 cm, the probability that radical surgery was highest in patients with central localization of the tumor.

Long-term strategy for the growth of the petroleum refining industry is based on the growth trends of those industries and other productive activities that are the largest consumers of engine fuels, boiler and furnace fuels, lubricating oils, and petrochemical feedstocks. Specialists have estimated that in the period 2000-2010, residual fuel oils will still account for 7-8% of the total consumption of fuel for heat and power generation in Russia. In our country, power generating plants are the greatest contributor to atmospheric pollution with substances that are harmful to human health, such as sulfur dioxide, nitrogen oxides, and particulate matter. Starting in 1991, limits have been placed on the specific emissions of sulfur and nitrogen oxides with stack gas from boiler units (no more than 400-600 and 185-290 mg/m{sup 3}, depending on size); also, standard penalty charges are being assessed for the emission of contaminants from industrial plants. With such standards, additional investment in environmental protection becomes economically advantageous. Power generating units that operate on liquid boiler fuel can meet these standards either by installing facilities to clean up the stack gas or by using low-sulfur fuel oil (0.3-0.4% sulfur by weight). As a consequence, questions of the quality of petroleum-derivedmore » boiler fuels are extremely important, as the effectiveness of the ecological policy of a country depends greatly on the selection of a strategy for environmental protection measures. This paper describes methods for the desulfurization of resids.« less

A generalization of the Harten TVD-scheme in the form of a predictor-corrector-type scheme of second-order accuracy in time and space is proposed for the flows with spherical and cylindrical symmetry. The scheme does not require introducing components with artificial viscosity and describes discontinuities in the solution without the appearance of nonphysical oscillations for a Courant number less than 0.8.

The results of investigating hot-fluid cavitating flow in a pipe with a local contraction are presented for a broad temperature interval (water from cold to near-boiling) and various cavitation regimes — from the initial (bubble) to the supercavitation regime. Experimental relations for the amplitudes of the fluctuations and the fundamental frequencies are presented for a Venturi tube with various diffusers and for diaphragms of various dimensions. A flow model which takes into account the fluctuations of the vapor pressure in the cavity and, moreover liquid-cavity mass transfer effects is presented. It is shown that for a given flow geometry there is a limiting Jakob number below which the self-oscillating regime is impossible at any cavitation numbers.

The authors have analyzed results of treatment of 26 patients with chronic pancreatitis complicated by pseudoaneurysms. Hospitalization and treatment of such patients should be performed in specialized hospitals which can fulfill special examination in detail and carry out roentgen-endovascular operations. Intraintestinal bleeding is an absolute indication for emergent surgery for performing hemostasis. Conservative treatment is indicated for intestinal bleedings and after arrest of bleeding the patients should be transported to specialized institutions. Two types of the appearance of pseudoaneurysms were established depending on the pathological mechanism: when there was a relationship of the pseudocyst with the main pancreatic duct (I type) and when there was not (II type). For the I type roentgen-endovascular treatment (RET) followed by operation is indicated, for the II type RET is thought to be enough.

The authors examined serum in patients with ovarian cancer (OC; a disseminated process), ovarian cystadenoma (OCA), or external endometriosis (EM) before treatment and in apparently healthy females (a control) for the content of some acute-phase proteins and cytokines to clarify the specific features of changes in their concentrations in relation to the type of the proliferative process. It was shown that in OC, there were significant reductions in the levels of alpha2-macroglobulin (MG), plasmin (PL), alpha1-antitrypsin (AT) and statistically significantly increases in the content of lactoferrin (LF), interleukin (IL)-6, IL-8, Ig, and the regulatory transport complex of P--M. In M, the concentrations of AT were lower and those of IL-6, IL-8, and PL-MG were higher (to a lesser degree than those in OC). In OCA, the levels of MG and IgA were increased; those of IL-8 and PL-MG were decreased. The concentrations of interferon and IgM were unchanged in all groups. The findings suggest that difefrent proliferative processes initially provoke a number of changes of varying magnitude and even directions in the serum levels of inflammation reactants, which should be borne in mind when conducting clinical tests in the intraoperative and, probably, postoperative periods.

The purpose of the study was to analyze the choice of agents for general anesthesia in the implementation of an early activation in patients operated on for coronary heart disease (CHD). Anesthetic maintenance protocols were analyzed in 1008 patients who were operated on under extracorporeal circulation (EC) in 1995, 1999, 2001, 2004, and 2006. After aortocoronary bypass grafting, the trachea was extubated in 45% of cases. 1999 was marked by a significant diference in the use of agents for general anesthesia in patients activated in the operating suite and in those who had prolonged artificial ventilation. In 2006, there were differences in the frequency of use of anesthetics in activated and inactivated patients. In 2006, the most popular anesthetics were propofol (82% of cases), midazolam (72%), isoflurane (37%), and sevoflurane (53%). The doses of fentanyl were reduced from 10.3 +/- 0.3 microg/kg/h in 1995 to 3.4 +/- 0.2 microkg/kg/h in 2006 (p0.05). During activation in the operating room, the frequency of naloxone use was reduced from 85.2% in 1999 to 21.1% in 2006 (p0.05). The authors paid particular attention to the pharmacodynamics of anesthetics used for the early activation of patients operated on under EC for CHD. It is concluded that early activation of patients operated on under EC for CHD is possible after general anesthesia based on diferent agents. Early activation substantially changes the concept of general anesthesia during myocardial revascularization operations.

177 patients with chronic pancreatitis and the pancreas head affection (CPPHA) were examined and these results were discussed. Option of the pancreatoduodenal resection (PDR) method was performed with due regard the greatest physiology of the operation and rare happening of the poor postoperative results. There are two methods operations of these patients--PDR or isolated resection of pancreas head (IRPH). Variations of IRPH have lesser the nearest unfa variable post operation results. There is no increase of postoperative lethality and complications if the right option and careful performance of IRPH (as Beger operation) was made.

The equilibrium distribution function of the intensities of two polarisation modes was obtained theoretically. This function is consistent with experimental results for a dye laser with transverse pumping polarised along the cavity axis.

The purpose of the study was to analyze the experience with fast-track activation of patients after myocardial revascularization with cardiopulmonary bypass (CPB) longer than 150 min and to study the efficiency of these procedures. The study included 64 ischemic patients (56 males and 8 females) aged 58.7+/-1 years, surged with CPB. In all cases, surgery and CPB were uncomplicated. The time of CPB was 151-298 (187+/-4) min; that of aortic cross-clamping was 67-181 (121+/-4) min. Hemodynamics, pulmonary gas exchange, and laboratory parameters were virtually normal before activation. Tracheal extubation was performed in the operating room 27-117 (61+/-3) min following the end procedure. The length of intensive care unit (ICU) stay was less than 24 hours in 82.8% of patients. The remaining patients stayed at an ICU 2-15 (2+/-1) days, which was associated with cardiac, pulmonary, renal complications, etc. The doses of dopamine and/or dobutamine and norepinephrine, and the index PO2a/FiO2 were shown to be predictors of ICU stay. It is concluded that fast-track activation is appropriate for patients undergoing prolonged CPB. The patients enrolled in the fast-track programme after prolonged CPB are to meet the following requirements: minimum inotropic and vasopressor support and PO2a/FiO2 greater than 350 mm Hg.

The purpose of the investigation was to study central hemodynamics and left ventricular function in low cardiac output after correction of aortic stenosis. The study included 34 patients (28 males and 6 females) aged 59. 7+/-1.5 years, surged with cardiopulmonary bypass (CPB). Low cardiac output was detected in all cases in the post-CPB period. Inotropic support with dopamine and/or dobutamine was effective in 47% of the patients (Group 1) and ineffective in 53% (Group 2). There were no statistically significant differences in cardiac index and pulmonary wedge pressure between the groups. Group 1 patients had ultrasound signs of left ventricular systolic dysfunction (low left ventricular ejection fraction and larger left ventricular systolic and diastolic areas in the transgastric position). Group 2 patients had ultrasound signs of left ventricular diastolic dysfunction (high left ventricular ejection fraction and smaller left ventricular systolic and diastolic areas). beta-blockers were used in 10 patients from Group 2. Central hemodynamics and left ventricular function normalized in all these cases. It is concluded that it is possible to recognize left ventricular dysfunctions in low cardiac output after aortic valve replacement with transesophageal echocardiography. Inotropic support is effective in only patients with left ventricular systolic dysfunction. Patients with left ventricular diastolic dysfunction should receive beta-blockers.

We study the structure of the confining string in Yang-Mills theory using the method of the field strength correlators. The method allows us to demonstrate that both the local fluctuations of the topological charge and the gluon condensate are suppressed in the vicinity of the string axis in agreement with results of lattice simulations., 10 pages, 3 figures, RevTeX 4.0

The purpose of the study was to reveal the predictors of more than 24-hour intensive care unit stay for patients activated early (up to 5 hours) after surgery under extracorporeal circulation and to explore the possibilities of predicting the prolongation of postoperative intensive care in the clinical situation under examination. The protocols of anesthetic maintenance, early activation, and postoperative intensive care were analyzed in 83 patients (50 males and 33 females) aged 31 to 82 years, who had been operated on under extracorporeal circulation for various cardiosurgical diseases. The multiple regression analysis showed that the significant predictors of more prolonged intensive care after early activation were the level of arterial lactatemia (p = 0.0021), the dosages of adrenaline and/or noradrenaline (p = 0.0048), age (p = 0.0051), and female sex (p = 0.0142). It was shown that the multiple regression analysis could approximately predict the duration of intensive care after early activation. The predicted and actual durations of intensive care in patients with an intensive care unit stay length of more than 24 hours coincided in 52% of cases. In patients with an intensive care unit stay length of less than 24 hours, the estimated and actual durations of intensive care were in agreement in 92% of cases. It is concluded that it is expedient to take into account the results of the performed analysis in choosing the optimum postoperative management policy in cardiosurgical patients who are to undergo early activation.

The author discusses some historical aspects of anesthesia for heart transplantation in Russia and other countries. The original study included 31 heart recipients aged 16 to 54. The duration of heart conservation was 2 to 6.6 hours. The optimal anesthesia consisted in a combination of fentanyl in low doses with midazolam and isoflurane. All the recipients needed intensive inotropic support with different sympathomimetic drug combinations following the reestablishment of transplanted heart functioning. There was a significant correlation between the duration of heart conservation and the doses of epinephrine (r = 0.51; p = 0.017). In most recipients with a duration of heart anoxic period of less than 2.5 hours, heart functioning proved to be possible to normalize with a dopamine-dobutamine combination. Epinephrine was the main agent in recipients with a longer period of heart anoxia. There was a significant correlation between the duration of heart conservation and systemic vascular resistance following cardio-pulmonary bypass. Epinephrine and norepinephrine were applied in combination with nitric oxide inhalation to prevent negative pulmonary vasoconstrictor effect of epinephrine and norepinephrine.

The spectral and polarization properties of fluorescence in dye solutions on two-photon excitation are studied. The conditions influencing a relative contribution of various mechanisms underlying the formation of a virtual intermediate state in the process of two-photon fluorescence excitation are determined. It is demonstrated that they are associated with the polarization and frequency characteristics of excitation fluxes and also with the electronic-vibrational molecular structure

The purpose of the study was to investigate arterial oxygenation and hemodynamics during and after alveolar mobilization in the early post-cardiopulmonary bypass (CPB) period of cardiac surgery. The study involved 21 patients aged 30 to 73 years, who had a PaO2/FiO2 below 300 mm Hg in the early post-CPB period. PaO2/FiO2 was less than 200 mm Hg in 4 patients. Alveolar mobilization was performed by means of the "Open lung tool" function of a Servo-i respirator ("Maquet'). PaO2/FiO2 significantly increased (P0.5) from 244+/-11 to 472+/-20 mm Hg and thoracopulmonary compliance (Cdyn) increased from 53.3+/-3 to 67.5+/-2.9 ml/cm H20 (p0.5). Intrapulmonary shunt (Qs/Qt) significantly decreased from 14+/-1 to 10+/-1.5% (p0.5). The mean values of PaO2/FiO2 Cdyn and Qs/Qt were stable at the end of procedures. PaO/FiO, was greater than 350 mm Hg in 62% of the patients. Cardiac index considerably decreased from 2.7+/-0.1 to 225+/-0.1 l/min/m(2) at the peak of alveolar mobilization (p0.05); right atrial pressure and mean pulmonary artery pressure were moderately, but significantly higher at that moment. Hemodynamic parameters returned to the baseline levels after alveolar mobilization. There were no significant hemodynamic complications. It is concluded that alveolar mobilization is an effective technique in improving arterial oxygenation and lung biomechanics in cardiosurgical patients under anesthesia.