31 research outputs found
Estimation of Possibility of Usage of Quasiazeotropic Mixture R134a/R152a in Refrigerating Engineering
DETECTION OF CAUSATIVE AGENTS OF TICK-BORNE INFECTIONS BY POLYMERASE CHAIN REACTION ASSAY CARRIED OUT AS A PART OF CLINICAL STUDIES IN THE “REPUBLICAN CLINICAL INFECTIOUS DISEASES HOSPITAL” OF ULAN-UDE
The article is devoted to the study of vector-borne pathogens circulating in the Republic of Buryatia. The authors have carried out identification of the genetic material of tick-borne encephalitis virus, Borrellia burgdorferi, Borrellia miуamotoi, Coxiella burnetii and Rickettsia sibirica in various samples of biological material. The object of the study were whole blood, leukocyte fraction and blood serum of patients admitted to the hospital in a state of fever that occurred after sucking of the tick, as well as mites brought by the population. A detailed analysis of the data showed that 11.7 % (9 out of 70) of the clinical material samples and 17.8 % (50 out of 281) of the tick samples had genetic markers of tick-borne pathogens. In the material from the patients, the RNA of tick-borne encephalitis virus was most often determined, and in the DNA of Borrellia burgdorferi mites. In addition, the authors first confirmed the etiologic role of Borrellia miуamotoi in the development of cases of Lyme disease in the Republic. An unexpected finding was the detection of Coxiella burnetii DNA in ticks and in clinical material. In the Republic of Buryatia Q-fever was detected by laboratory diagnostics for the first time. This fact confirms the circulation of this pathogen in the region. In this regard, the authors conducted a retrospective analysis of the medical histories of patients who were found to have genetic markers of Q-fever
Fluctuational escape from chaotic attractors in multistable systems.
Recent progress towards an understanding of fluctuational escape from chaotic attractors (CAs) is reviewed and discussed in the contexts of both continuous systems and maps. It is shown that, like the simpler case of escape from a regular attractor, a unique most probable escape path (MPEP) is followed from a CA to the boundary of its basin of attraction. This remains true even where the boundary structure is fractal. The importance of the boundary conditions on the attractor is emphasized. It seems that a generic feature of the escape path is that it passes via certain unstable periodic orbits. The problems still remaining to be solved are identified and considered
Data-driven approach to the estimation of connectivity and time delays in the coupling of interacting neuronal subsystems.
One of the challenges in neuroscience is the detection of directionality between signals reflecting neural activity. To reveal the directionality of coupling and time delays between interacting multi-scale signals, we use a combination of a data-driven technique called empirical mode decomposition (EMD) and partial directed coherence (PDC) together with the instantaneous causality test (ICT). EMD is used to separate multiple processes associated with different frequency bands, while PDC and ICT allow to explore directionality and characteristic time delays, respectively. We computationally validate our approach for the cases of both stochastic and chaotic oscillatory systems with different types of coupling. Moreover, we apply our approach to the analysis of the connectivity in different frequency bands between local field potentials (LFPs) bilaterally recorded from the left and right of subthalamic nucleus (STN) in patients with Parkinson's disease (PD). We reveal a bidirectional coupling between the left and right STN in the beta-band (10-30 Hz) for an akinetic PD patient and in the tremor band (3-5 Hz) for a tremor-dominant PD patient. We detect a short time delay, most probably reflecting the inter-hemispheric transmission time. Additionally, in both patients we observe a long time delay of approximately a mean period of the beta-band activity in the akinetic PD patient or the tremor band activity in the tremor-dominant PD patient. These long delays may emerge in subcortico-thalamic loops or longer pathways, comprising reflex loops, respectively. We show that the replacement of EMD by conventional bandpass filtering complicates the detection of directionality and leads to a spurious detection of time delays
Fucoidan Sulfatases from Marine Bacterium Wenyingzhuangia fucanilytica CZ1127T
Fucoidans belong to a structurally heterogeneous class of sulfated polysaccharides isolated from brown algae. They have a wide spectrum of biological activities. The complex structures of these polysaccharides hinder structure-activity relationships determination. Fucoidan sulfatases can make useful tools for the determination of the fine chemical structure of fucoidans. In this study, identification and preparation of two recombinant sulfatases able to catalyze the cleavage of sulfate groups from fragments of fucoidan molecules is described for the first time. Two genes of sulfatases swf1 and swf4 of the marine bacterium Wenyingzhuangia fucanilytica CZ1127T were cloned and the proteins were produced in Escherichia coli cells. Sulfatases SWF1 and SWF4 are assigned to S1_17 and S1_25 subfamilies of formylglycine-dependent enzymes of S1 family (SulfAtlas). Some molecular and biochemical characteristics of recombinant fucoidan sulfatases have been studied. Detailed specificity and catalytic features of sulfatases were determined using various sulfated fucooligosaccharides. Structures of products produced by SWF1 and SWF4 were established by nuclear magnetic resonance (NMR) spectroscopy. Based on the obtained data, the enzymes are classified as fucoidan exo-2O-sulfatase (SWF1) and fucoidan exo-3O-sulfatase (SWF4). In addition, we demonstrated the sequential action of sulfatases on 2,3-di-O-sulfated fucooligosacchrides, which indicates an exolitic degradation pathway of fucoidan by a marine bacterium W. fucanilytica CZ1127T
Dynamic State Analysis of Waveguide Distribution Systems from Vibration Loads Effects While Launching Spacecraft Into the Orbit
Рассматривается проблемный вопрос исследования и обеспечения требуемого
динамического напряженно-деформированного состояния волноводно-распределительных
систем от воздействия вибрационных нагрузок на этапе вывода космических аппаратов
связи на орбиту. Разработаны методы анализа динамического состояния применительно
к любым конструктивным особенностям волноводно-распределительным систем
космических аппаратов связи, реализованные в созданном программном обеспечении.The problem question of research and providing the demanded dynamic stress state and deformed
conditions of waveguide-distributive systems from influence of vibrating loadings at a stage of a
conclusion of communication satellite into an orbit is considered. Methods of the analysis of a dynamic
condition with reference to any design features waveguide-distributive systems of communication
satellite realized in the created software are developed
Dynamic State Analysis of Waveguide Distribution Systems from Vibration Loads Effects While Launching Spacecraft Into the Orbit
Рассматривается проблемный вопрос исследования и обеспечения требуемого
динамического напряженно-деформированного состояния волноводно-распределительных
систем от воздействия вибрационных нагрузок на этапе вывода космических аппаратов
связи на орбиту. Разработаны методы анализа динамического состояния применительно
к любым конструктивным особенностям волноводно-распределительным систем
космических аппаратов связи, реализованные в созданном программном обеспечении.The problem question of research and providing the demanded dynamic stress state and deformed
conditions of waveguide-distributive systems from influence of vibrating loadings at a stage of a
conclusion of communication satellite into an orbit is considered. Methods of the analysis of a dynamic
condition with reference to any design features waveguide-distributive systems of communication
satellite realized in the created software are developed
Fluctuational Transitions through a Fractal Basin Boundary.
Fluctuational transitions between two coexisting chaotic attractors, separated by a fractal basin boundary, are studied in a discrete dynamical system. It is shown that the transition mechanism is determined by a hierarchy of homoclinic points. The most probable escape path from a chaotic attractor to the fractal boundary is found using both statistical analyses of fluctuational trajectories and the Hamiltonian theory of fluctuations