ABSTRACT
A single radiation-induced superoxide ion [Formula: see text] has been observed for the first time in metal oxides. This structural defect has been revealed in fast-neutron-irradiated (6.9×1018 n/cm2) corundum (α-Al2O3) single crystals using the EPR method. Based on the angular dependence of the EPR lines at the magnetic field rotation in different planes and the determined g tensor components, it is shown that this hole-type [Formula: see text] center (i) incorporates one regular and one interstitial oxygen atoms being stabilized by a trapped hole (S = 1/2), (ii) occupies one oxygen site in the (0001) plane being oriented along the a axis, and (iii) does not contain any other imperfection/defect in its immediate vicinity. The thermal stepwise annealing (observed via the EPR signal and corresponding optical absorption bands) of the [Formula: see text] centers, caused by their destruction with release of a mobile ion (tentatively the oxygen ion with the formal charge -1), occurs at 500-750 K, simultaneously with the partial decay of single F-type centers (mostly with the EPR-active F+ centers). The obtained experimental results are in line with the superoxide defect configurations obtained via density functional theory (DFT) calculations employing the hybrid B3PW exchange-correlation functional. In particular, the DFT calculations confirm the [Formula: see text] center spin S = 1/2, its orientation along the a axis. The [Formula: see text] center is characterized by a short O-O bond length of 1.34 Å and different atomic charges and magnetic moments of the two oxygens. We emphasize the important role of atomic charges and magnetic moments analysis in order to identify the ground state configuration.
ABSTRACT
AIM: to investigate the possibility of a new method--interval hypo-hyperoxic training (IHHT)--in the correction of the individual components of metabolic syndrome. MATERIALS AND METHODS: The study included 35 patients with metabolic syndrome (alimentary obesity 1-3rd stage [BMI over 30 kg/m2], violation of carbohydrate tolerance or diabetes mellitus type II, hypertension and dyslipidemia). All patients were random separated into three groups: control (11 pers., basic therapy), trial 1 (13 pers. who have undergone 12 procedures of the IHHT) and trial 2 (11 pers. who have undergone IHHT in parallel with systemic hyperthermia and vibrating massage hardware). Course duration was 21 days average. Prior to the course procedures IHHT and the 3-day 4 upon completion all patients were fully examined. This examination included history taking, assessment of diet, psychometric testing, counseling psychologist to determine the type of feeding behavior, anthropometric measurements; body impendansemetria, biochemical study of blood determining the level of total cholesterol, HDL, LDL, TG, fasting plasma glucose (GP), 6-minute walk test to assess physical performance. Was established that the use of hypo-hyperoxic exercise (alone or in combination with systemic hyperthermia and hardware vibratory) leads to a significant reduction in body weight. It mainly arise by reducing fat mass accompanied by a reduction of total cholesterol, LDL, GPN, optimization of blood pressure, increased hypoxic stability, physical endurance, improved mental status. At individual selection of the course structure, dosing of hypoxic effects, combined with other physiotherapy method has some promise in treatment and rehabilitation of patients with metabolic syndrome.
