Analysis of the Influence of the Degree of Increase in the Pressure of the Working Fluid in the Turbocharger on the Efficiency of the Gas Turbine Plant

Экономичность газотурбинного цикла существенно зависит от степени повышения давления и степени повышения температуры рабочих тел (циклового воздуха и газов). Рассмотрено влияние степени повышения давления рабочего тела в турбокомпрессоре и начальной температуры газов на КПД и мощность газотурбинной установки. Проведены численные расчеты. По результатам исследования установлено, что каждому значению степени повышения температуры соответствует свое оптимальное значение степени повышения давления, при котором КПД установки принимает максимальное значение. Причем с увеличением значения степени повышения температуры максимальное значение КПД газотурбинной установки смещается в сторону возрастания величины степени повышения давления.The efficiency of the gas turbine cycle significantly depends on the degree of pressure increase and the degree of temperature increase of the working bodies (cyclic air and gases). The influence of the degree of increase in the pressure of the working fluid in the turbocharger and the initial temperature of the gases on the efficiency and power of the gas turbine installation is considered. Numerical calculations are carried out. According to the results of the study, it was found that for each value of the degree of temperature increase, its optimal value corresponds to the degree of pressure increase, at which the efficiency of the installation takes the maximum value. Moreover, with an increase in the value of the degree of temperature increase, the maximum value of the efficiency of the gas turbine installation shifts towards an increase in the magnitude of the degree of pressure increase

The use of creatine phosphate in the complex therapy of patients with myocardial infarction during posthospital rehabilitation

The aim of the study - to determine the effect of creatine phosphate on exercise tolerance and systolic and diastolic functions of the left ventricle in patients who suffered a myocardial infarction with ST elevation during post-hospital rehabilitationЦель исследования – определить влияние креатинфосфата (КФ) на толерантность к физической нагрузке, систолическую и диастолическую функции левого желудочка у больных перенесших инфаркт миокарда с подъемом ST в период постгоспитальной реабилитаци

LONG-TERM RESULTS OF DIFFERENT UV-CROSSLINKING TECHNIQUES IN PATIENTS WITH PROGRESSIVE KERATOCONUS

Purpose. To compare a clinical effectiveness of different UV-crosslinking techniques in patients with progressive keratoconus.Material and methods. Randomized prospective clinical trial included 130 eyes of 117 keratoconic patients. There were created 2 equal groups of 65 eyes. In the group I patients underwent a classical UV-crosslinking technique with a complete central corneal deepithelialization, in the group II a UV-crosslinking with dosed corneal epithelium scarification was performed using a new device. The postoperative follow-up period was 24 months. Preoperatively in the group I the uncorrected visual acuity (UCVA) was 0.21±0.11, the best corrected visual acuity (BCVA) was 0.49±0.14, the central corneal pachymetry (CCP) – 469.1±23/4μm, the mean keratometry (Kave) – 46.1±1.7D, in the group II: UCVA was 0.22±0.09, BCVA – 0.48±0.12, CCP – 475.2±28.5μm, Кave – 46.7±1.4D.Results. The mean postoperative pain score was 6.9±1.3, relief on the 3-rd ±1.2 day post-op. in the group I, and 2.8±1.1 relief on the 1-st±0.4 day post-op. in the group II. All patients had a 0.1 to 0.12 visual acuity loss 7 days after the surgery that was due to a mild corneal opacification. At 3 months after operation in both groups the UCVA and the BCVA were back to their preoperative values. In the group I the UCVA increased by 0.07±0.03 (р<0.05) 2 years after the treatment, the BCVA increased by 0.11±0.04 (р<0.05). At that time in the group II the similar values were obtained: 0.08±0.02 (р<0.05), 0.1±0.04 (р<0.05) respectively. The Kave index in both groups gradually decreased during first 12 months after operation and then stabilized. At the end of the follow up it was lower by 2.6±0.5D (р<0.05) in the group I and by 2.4±0.3D (р<0.05) in the group II. According to the anterior OCT, the depth of demarcation line was 327±11μm in the group I and 318±13μm in the group II. The demarcation line was absent in all cases 12 months after surgery. In the early postoperative period 3 months after operation the CCP gradually decreased. It reduced by 3.77±0.83% (р<0.05) in the group I and by 3.17±0.88% (р<0.05) in the group II. After that the CCP slowly increased during the entire follow-up, but 24 months later it was still lower by 2.36±0.57% (р<0.05) in the group I and by 1.68%±0.75 (р<0.05) in the group II. Confocal microscopy 1 month after surgery revealed typical changes of corneal structure at the depth up to 310±9μm (290 to 335) in the group I and 300±8μm (280 to 330) in the group II. A full reinnervation and the repopulation of the cornea with keratocytes was seen 6 months after operation. The only complication (delayed corneal epithelization) was in the group with classical UV-crosslinking technique.Conclusions. The trial revealed similar clinical outcomes after classical UV-crosslinking technique and UV-crosslinking with dosed corneal epithelium scarification, however in the latter case during the postoperative period the severity and duration of pain were significantly reduced

Динамика выживаемости больных муковисцидозом в Москве и Московской области за периоды 1992–2001 и 2002–2011 гг.

Summary. The aim of this study was to evaluate changes in survival of patients with cystic fibrosis (CF) in Moscow and Moscow region and to determine factors influencing the survival. We analyzed outpatient medical records of patients followed-up in Moscow CF centers by the 1st of January, 2002, and by the 1st of January, 2012.Median survival for 2002–2012 was 37.2 years; this was significantly higher that the similar value for the previous decade (25.9 years). A total number of CF patients was more than doubled due to increased survival and improved diagnosis of the disease.Improved survival was due to improved work of CF centers and to implementation of effective medications, primarily dornase alfa (Pulmozyme) and some inhaled and systemic antibiotics and macrolides in subinhibitory concentrations, in routine clinical practice. Gram-negative infection, especially Burkholderia cepacia, was shown to decrease survival in CF patients in contrary to "mild" mutations that are better prognostic factors.Резюме. Целью работы явилось определение динамики числа и выживаемости больных муковисцидозом (МВ) в Москве и Московской области, а также определение факторов, влияющих на выживаемость. Были проанализированы амбулаторные карты больных, состоящих на учете в московских центрах муковисцидоза на 01.01.2002 и 01.01.2012.Медиана выживаемости больных за периоды 2002–2011 гг. составила 37,2 года, что достоверно выше, чем аналогичный показатель за предыдущее 10-летие – 25,9 года. Отмечено более чем 2-кратное увеличение общего количества больных, обусловленное ростом выживаемости и улучшением диагностики.Увеличение выживаемости обусловлено оптимизацией работы центров МВ и началом рутинного применения различных эффективных медикаментозных препаратов, прежде всего дорназы альфа (Пульмозим), а также некоторых ингаляционных и системных антибиотиков, макролидов в субингибирующих концентрациях. Показано, что инфицирование грамотрицательной инфекцией, особенно Burkholderia cepacia, снижает выживаемость пациентов с МВ, а наличие "мягкого" генотипа является более благоприятным прогностическим фактором

Hemodynamic, electrophysiological and biochemical properties of the visual system of patients with severe destructive changes of the vitreous

The study (as the main group) 84 patients (84 eyes) aged 42-76 years with severe destructive changes of the vitreous (VDIST), as a control group examined 32 patients of appropriate age and sex, with little or no pathology of the vision. It was found that the occurrence of VDIST accompanied by significant enough violations of hemodynamic and biochemical parameters of the visual system, as well as the parameters of microcirculation. It is assumed that the significantly reduced level of functioning of visual analyzer patients with severe VDIST can be considered as one of the leading risk factors for the development of further more serious vitreoretinal disorders (retinal detachment, macular holes)

Clinical efficacy of vitrectomy when expressed destructive changes in the vitreous

Purpose: Conducting complex (clinical, hemodynamic, subjective) evaluate the effectiveness of vitrectomy in patients with expressed destructive changes in the vitreous (CT).Patients and methods. We observed 74 patients (86 eyes, mean age 63.4 years) with severe destructive changes CT manifested almost constant presence of «flying flies» in front of his eyes. Subtotal vitrectomy was performed by standard methods using instruments 25-30G with intraoperative use of a standard balanced salt solution (Balansed Salt Solution, BSS), further enriched with the introduction of an antioxidant (glutathione) in all patients in the main group.Results. Vitrectomy in patients with acute ST destructive changesassociated with significantly positive parametres of microcirculation (by 24,7 % –30,7 %, p <0,05) and subjective status (at 12,7 %, p <0,05), the progress after the surgery performance was not significantly different from that of the control group. There was a trend (p> 0,05) of increasing the maximum correctable visual acuity and the degree of lens opacity after surgery. The results of the the postoperative survey have shown that 92 % of patients were completely satisfied with the outcomes of operations (6 % — not satisfied, 2 % — had difficulties with answer). Subjectively, significant improvement in vision after surgery indicated in 62 % patients, eyesight was better — 26 %, unchanged — 10 %; blurred vision — 2 %. Our results regarding the dynamics of microcirculation suggest that surgical removal of the CT in expressed destructive changes lead to the normalization of the eyeball microvasculare perfusion. It is accompanied with the restoration of the natural balance between the arteriolar influx and venular outflow, as well as between the active and passive components of the regulatory microhemodynamics. These changes are responsible for the improvement of metabolic processes in the tissues of the eyeball, contributing to maintain a constant temperature and transparency of the CT, which generally provides the necessary prevention of postoperative complications in the retina

Supplementary Material for: Steady-State Therapy with Azithromycin or Low-Dose Prednisolone in Paediatric Cystic Fibrosis Patients: Inflammatory Markers and Disease Progression

<i>Background:</i> Anti-inflammatory therapy is a logical approach to slowing the inevitable lung function deterioration in cystic fibrosis (CF) patients. This study's aim was to evaluate inflammatory markers and disease progression in paediatric CF patients chronically treated with azithromycin or low-dose prednisolone.<i> Methods:</i> The study included 204 patients with CF and 100 healthy controls; 102 CF patients were treated with basic therapy only (without anti-inflammatory treatment; WAT), and 102 individuals received basic therapy along with azithromycin (<i>n</i> = 59) or low-dose prednisolone (<i>n</i> = 43). The median duration of therapy was 24 months (range 12-82) with azithromycin and 31 months (range 12-180) with prednisolone. A cross-sectional analysis of plasma and sputum biomarkers was performed. <i>Results:</i> Compared with the healthy controls, the WAT group showed elevated IFN-γ, IL-10 (total), and TGFβ1 concentrations, and decreased TNFα (total) and adrenocorticotropic hormone (ACTH) levels (all <i>p</i> < 0.05). Plasma TNFα (total) concentrations in azithromycin/prednisolone patients were significantly higher than those in WAT patients and similar to those of healthy children. In contrast, IL-10 (total) levels were significantly decreased in azithromycin/prednisolone-treated patients compared with WAT patients. Children from the azithromycin group demonstrated ACTH levels similar to those of healthy controls. Azithromycin-treated patients showed a significantly reduced rate of CF-related liver disease and a significantly increased incidence of glucose metabolism disturbances. <i>Conclusions:</i> Steady-state anti-inflammatory treatments may have a sustained immunomodulatory action at systemic and local levels in CF patients. Further investigations are needed to assess the effects of supportive azithromycin therapy on the hypothalamic-pituitary-adrenal axis and the incidence of non-pulmonary CF complications

MICROFLORA OF THE RESPIRATORY TRACT IN PATIENTS WITH CYSTIC FIBROSIS AND SENSITIVITY TO ANTIBIOTICS BASED ON A 15-YEAR FOLLOW-UP (2000–2015 YEARS)

Chronic lower respiratory tract infection in patients with cystic fibrosis (CF) is the major factor determining the severity of the clinical course and prognosis of the disease. The purpose of the study was to investigate the prevailing respiratory microflora in patients with CF and changes in the activity of antibacterial medicines (ABM) during the period 2000–2015 in order to optimize guidelines for antibiotic therapy. Bronchial secretion was evaluated in CF patients from 2000 till 2015. 9774 samples were studied, 16.703 microbial strains were obtained. In 2000–2015, P. aeruginosa (smooth and mucoid morphological types) was the most widespread gram-negative strain. Typical strains of P. aeruginosa were isolated more often than mucoid morphotypes. In 2000–2015, isolation rates for P. aeruginosa decreased from 41.2 to 20.0% (p &lt;0.001). The proportion of B. cepacia complex increased from 1.1 to 7.3%, up to 11.3% in 2008–2011, and a rise in the proportion A. xylosoxidans was registered from 2.9 to 4.9% (p &lt;0.001). During the follow-up period, the diversity of isolated species has grown.ABM such as colistin (active against 100% of strains), carbapenems (imipenem is active against 70.3–72.2% of strains, and meropenem against 75.8 and 78.9%) remain active against P. aeruginosa. The effect of piperacillin/tazobactam is similar to that of carbapenems. Cefepime is less effective than ceftazidime. Fluoroquinolones and tobramycin also remian active