ABSTRACT
Radiation shielding composites based on polyimide and Bi2O3 were synthesized. Surface and physical-mechanical properties of polyimide/Bi2O3 composites were studied. Bi2O3 particles were modified by polymethylphenylsiloxane for the uniform distribution of filler in composites. This paper presents data on the production of composites in two ways: hot- and cold-pressing. The hot-pressing method for the synthesis of composites is preferable compared to the cold-pressing method (the density increases by 10-12%, and the Vickers microhardness by 10-20%). The results show that the introduction of Bi2O3 significantly increases the thermal stability of the composites. At 680 °C, a polymer composite containing 10 wt% Bi2O3 retains 9.7% of its mass, and at 60 wt% Bi2O3, retains 58.4%. The radiation-protective characteristics of the composites with respect to gamma radiation were evaluated by experimental and theoretical methods. High radiation-protective characteristics of the composites have been established in the gamma-quanta energy range of 0.1-1 MeV.
ABSTRACT
Aim of the study was to investigate prevalence and special characteristics of manifestations of painless myocardial ischemia (PMI) in patients with chronic obstructive pulmonary disease (COPD) at exacerbation stage with various degree of severity and to assess risk of cardiovascular events in this group of patients. We carried out complex clinical-instrumental and laboratory examination of 54 patients with COPD. Examination included 24 hour Holter ECG monitoring, registration of parameters of pulmonary function, and endothelium dependent and independent vasoreactivity, determination of lipid spectrum, blood gases composition. We established that aggravation of degree of COPD severity was associated with increase of frequency of episodes of PMI and their total daily duration. During 12 months follow up incidence of cardiovascular events in the group of patients with episodes of PIM was 66.6%
Subject(s)
Asymptomatic Diseases/epidemiology , Myocardial Ischemia , Pulmonary Disease, Chronic Obstructive/complications , Electrocardiography, Ambulatory/methods , Follow-Up Studies , Humans , Incidence , Male , Middle Aged , Myocardial Ischemia/diagnosis , Myocardial Ischemia/epidemiology , Myocardial Ischemia/etiology , Myocardial Ischemia/physiopathology , Pulmonary Disease, Chronic Obstructive/physiopathology , Respiratory Function Tests/methods , Risk Assessment , Risk Factors , Severity of Illness IndexABSTRACT
The hospital-based rehabilitative treatment was given to 36 patients presenting with combined cardiopulmonary pathology. It included electrophoresis of the the salt sediment from Amurskaya-2 mineral water and the assessment of its efficacy in clinical, functional, and laboratory studies. It was shown that this therapeutic modality had positive influence on lipid metabolism and improved the functional state of myocardium. Overall, the rehabilitative potential of the treatment increased.
