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In this research, the one-dimensional fluid code SIGLO-rf was used to study the internal parameters of RF capacitive discharge in carbon dioxide, focusing mainly on time-averaged and spatio-temporal distributions of discharge parameters. With the help of this code, in the range of distances between electrodes d = 0.04 – 8 cm, RF frequencies f = 3.89 – 67.8 MHz, and values of carbon dioxide pressure p = 0.1 – 9.9 Torr, averaged over the RF period axial profiles of the density of electrons, positive and negative ions were calculated as well as potential and electric field strength. It is shown that the discharge plasma in CO2 contains electrons, positive ions, as well as negative ions. The negative ions of atomic oxygen are formed by the dissociative attachment of electrons to CO2 molecules. Studies of the spatio-temporal dynamics of plasma parameters (electron density, potential and electric field strength, as well as ionization and attachment rates) in RF capacitive discharge in CO2 showed that during half of the RF period, 1 to 3 ionization bursts are usually observed. They correspond to stochastic heating in the near-electrode sheath and the formation of passive and active double layers near the sheath boundaries. The passive double layer appears in the cathode phase and maintains the discharge plasma. The active layer is formed in the anodic phase and ensures a balance of positive and negative charges escaping to the electrode during the RF period. It was found that when the conditions pd = 2 Torr cm and fd = 27.12 MHz cm are met simultaneously, during half of the RF period, 4 intense ionization peaks are observed: resulting from stochastic heating, passive, active, and additional (auxiliary) double layers. The auxiliary double layer helps bring electrons to the surface of the temporary anode and occurs near its surface inside the near-electrode sheath. Using the similarity law, the conditions for the existence of these 4 ionization peaks in a wide range of RF frequencies, carbon dioxide pressures, and distances between electrodes were verified.

In this research, the one-dimensional fluid code SIGLO-rf was used to study the internal parameters of RF capacitive discharge in carbon dioxide, focusing mainly on time-averaged and spatio-temporal distributions of discharge parameters. With the help of this code, in the range of distances between electrodes d = 0.04 – 8 cm, RF frequencies f = 3.89 – 67.8 MHz, and values of carbon dioxide pressure p = 0.1 – 9.9 Torr, averaged over the RF period axial profiles of the density of electrons, positive and negative ions were calculated as well as potential and electric field strength. It is shown that the discharge plasma in CO2 contains electrons, positive ions, as well as negative ions. The negative ions of atomic oxygen are formed by the dissociative attachment of electrons to CO2 molecules. Studies of the spatio-temporal dynamics of plasma parameters (electron density, potential and electric field strength, as well as ionization and attachment rates) in RF capacitive discharge in CO2 showed that during half of the RF period, 1 to 3 ionization bursts are usually observed. They correspond to stochastic heating in the near-electrode sheath and the formation of passive and active double layers near the sheath boundaries. The passive double layer appears in the cathode phase and maintains the discharge plasma. The active layer is formed in the anodic phase and ensures a balance of positive and negative charges escaping to the electrode during the RF period. It was found that when the conditions pd = 2 Torr cm and fd = 27.12 MHz cm are met simultaneously, during half of the RF period, 4 intense ionization peaks are observed: resulting from stochastic heating, passive, active, and additional (auxiliary) double layers. The auxiliary double layer helps bring electrons to the surface of the temporary anode and occurs near its surface inside the near-electrode sheath. Using the similarity law, the conditions for the existence of these 4 ionization peaks in a wide range of RF frequencies, carbon dioxide pressures, and distances between electrodes were verified. [ABSTRACT FROM AUTHOR]

AIM: To identify risk and prognostic factors for mitral regurgitation (MR) progression after aortocoronary bypass surgery (ACBS) alone and in combination with surgical left ventricular (LV) reconstruction/MATERIAL AND METHODS: Data on 101 patients with coronary heart disease who had undergone surgical treatment: ACBS alone in 57 (56%) patients and that in combination with surgical LV reconstruction in 44 (44%)/RESULTS: In the late periods after ACBS alone, there was reduced or no MR in 18% of the patients; no substantial changes in MR in 52%, the latter being moderate; progression to significant mitral insufficiency (MI) in 30%. In the same periods after ACBS in combination with surgical LV reconstruction, there was a reduction in MR to its minimum or complete absence in 14% of the patients; no substantial change in the degree of MR in 54%, and progression to significant MI in 32%. The prognostic factors of MI progression after ACBs alone and in combination with surgical LV reconstruction were a more than 32-mm fibrous ring of the mitral valve (MV) (χ2=11.62; р=0.0001); a LV sphericity index of more than 0.65 cm (χ2=3.38; р=0.06); a myocardial scar lesion extent of more than 30% of the LV segments (χ2=4.7; р=0.03); a myocardial reserve of less than 25% (χ2=3.1; р=0.07) (when taking low-dose dobutamine)/CONCLUSION: Myocardial revascularization should be combined with MV intervention in patients with moderate MR and risk factors for its progression, such as significant LV remodeling (LV sphericity index of more than 0.65 cm), extensive LV scar lesion (more than 30% of the segments), a low myocardial reserve (less than 25%) during dobutamine test, and a MV fibrous ring of more than 32 mm).

AIM: To define the prognostic value of evaluation exercise-induced myocardial ischemia according to the data of pharmacological (dobutamine or dipyridamole) stress echocardiography (EchoCG) in patients with acute coronary syndrome (ACS). /MATERIAL AND METHODS: The results of examinations were analyzed in a total of 91 patients with ACS. An analysis of events in the established follow-up period (mean 14.3±0.7 months) took into consideration outcomes, such as death from cardiac diseases, a recurrent acute coronary episode (nonfatal myocardial infarction (MI), unstable angina (UA) /RESULTS: Pharmacological stress EchoCG showed a positive result in 40 (44%) patients (Group 1) and a negative one in 51 (56%) patients (Group 2). Thus, the sensitivity and specificity of the pharmacological test in determining the risk for cardiac events were 89.3 and 76.2%, respectively; the prognostic value of positive and negative results was 62.5 and 94.1%, respectively. Analysis of EchoCG parameters used to identify poor prognostic factors in patients with ACS has indicated that the most important predictors of death and major cardiac events (cardiac death, acute MI, UA) are resting impaired segmental contractility index (ISCI), number of asynergic segments, and total ejection fraction (TEF) at baseline; TEF, ISCI, ΔISCI (as compared to the baseline data), and the number of segments with a negative response after low-dose drug infusion; a positive or negative result, TEF, ΔTEF (as compared to the baseline data), and ISCI at the test peak /CONCLUSION: Pharmacological stress EchoCG is a safe noninvasive diagnostic method in a group of patients with ACS. When the latter is diagnosed, it may be performed in the earliest periods (on day 4 after onset of the disease) to estimate its prognosis and to decide whether aggressive treatments should be used.

Aim. To define the prognostic value of the indicators of left ventricular myocardial viability according to the data of pharmacological stress echocardiography in patients with acute coronary syndrome (ACS). Materials and methods. The results of examinations were analyzed in a total of 91 patients with ACS; 71 of them were found to have areas of asynergy (these cases formed the key basis for statistical processing). An analysis of the outcomes registered in the established follow-up period (mean 14.3±0.7 months) took into consideration death from cardiac diseases, a recurrent acute coronary episode (nonfatal myocardial infarction (MI), unstable angina (UA)). Results. Risk stratification for cardiac events in patients with ACS requires both the assessment of a myocardial viability testing result and the detection of stress-induced ischemia. An analysis of the impact of the indicators of myocardial viability on prognosis in the ACS group showed that the most important predictors of cardiac death were impaired segmental contractility index (ISCI), number of asynergic segments, and total ejection fraction (TEF) at rest; TEF, ISCI, number of segments with a negative response to low-dose drug infusion; TEF, ΔTEF (as compared to the baseline data), and a positive or negative peak stress testing result. The most important predictors of major cardiac events (death MI, UA) were ascertained to be ISCI, number of asynergic segments, resting TEF; TEF, ISCI, number of segments with a negative response to low-dose drug infusion; a positive or negative testing result, TEF, ΔTEF (as compared to the baseline data), and ISCI during the peak stress test. Conclusion. The low myocardial/coronary reserve increases mortality rates; the high one worsens the prognosis of major cardiac events, particularly when the test is positive, which tacitly transfers these patients to a very high risk group.

The town of Tuapse, on Russia’s Black Sea Coast, has recently been granted the status of “Gorod Voinskoi Slavy” (town of military glory). This pronouncement has created space for public discussion and civic activity regarding the contribution of the Tuapsinskii district (a part of Krasnodarskii Krai) to the war effort, a subject about which there is a lack of academic literature. As official discourse doesn’t indicate the role played by ethnic minorities during the war, the Tuapse Armenian Community (a division of Soiuz Armian Rossii – Union of Armenians of Russia), which represents local Hamshen Armenians, has decided to erect at least three monuments dedicated to Great Patriotic War heroes of Armenian descent: Admiral Isakov of the Gornii village, and three heroes from the Shaumian village – Melkonian, Snoplian, Shalzhiian. With this community activity bringing memories of the war to the forefront, the authors have chosen to draw on the experiences of the actual participants in the war, some of which are still alive and can readily give first-hand information about the situation. The authors have conducted in-depth (biographical) interviews, as well as an analysis of the existing Soviet and post-Soviet literature on the topic. Preliminary review of publications has shown ambivalence or even misrecognition of the contribution of non-Russians groups to the victory over the Nazis. The article focuses on Hamshen Armenian villagers’ everyday life in the context of the 1941-1945 war in order to address the gap in scholarly literature through extracts from the collective memory. The authors apply both history and anthropology and by putting them together transgress the disciplinary borders. The questions this research raises are: Is our understanding of the war effort important to our understanding of the Hamshen community? Do we need to counter mainstream "grand narratives" with local knowledge?

The article deals with young veterans of the Karabakh War (1991-1994). It is focused on ordinary teenagers whose lives became part of warfare. The harsh, shocking hardships they experienced during the war are far from being named “youth culture of leisure” (that is to say youth sub/contra culture as a social phenomenon, rather than biological age scale). It seems that those adolescents have skipped a stage of their lives. The article touches upon the young veterans’ Post-Traumatic Stress Disorder (PTSD) syndrom and how they try to overcome it. Some of them are still traumatized by the consequences of war after more than a decade. Some have undergone identity-transformations that affect their present life trajectories.

Based on the narratives collected by the author, analyzes social transformations during the 1988-94 military conflict in Nagorno-Karabakh, during which tendencies of demodernization of economic life became obvious, while return to old patriarchal models turned into a strategy of resistance and survival. In the social context during and after the war, the traditionalist discourse acquired an official and dominant status. The ethics of survival dictated models of adaptation that minimally guaranteed existence through mechanisms of redistribution. Despite the discourse of the idealization of solidarity, the moral economy of survival is characteristic of poor and stagnating societies. In these societies, the space of female activity (that is, household) and passivity is clearly demarcated from the space of male articulation and defense of the nation.