Model studies were carried out using the COMSOL Multiphysics package, aimed at ensuring the forming of a permanent magnet magnetic field at a considerable distance to a ferromagnetic product from its ...pole, which is necessary to create efficient portable ultrasonic electromagnetic-acoustic transducers of thickness gauges and testing and diagnostic devices. It is theoretically shown and experimentally confirmed that for portable measuring ultrasonic devices it is expedient to set the height of the permanent magnet at about 60 mm and the cross section of the magnet pole 50x50 mm2. At the same time, with a gap between the magnet pole and the product of about 30 mm, the value of the normal component of the magnetic field induction near the surface of the object is about 0.3...0.4 T, which is sufficient for thickness gauging or diagnostics of ferromagnetic products using the ultrasonic pitch-and-catch method. References 19, figures 8.
The fully reduced activation brazing alloy TiZr4Be and a tantalum intermediate layer are considered to be used for joining tungsten (W) to reduced-activation ferritic-martensitic steel (RAFM) for ...future DEMO reactor application. Deuterium retention in the W-Rusfer joints and separate elements was investigated with the focus on the intermediate brazing layer. The samples were exposed in deuterium gas (p = 1–104 Pa, T = 300–600°C) and plasma discharge (T = 600°C). An acceptable deuterium concentration was observed after gas exposure at the pressure of 1 Pa, that is relevant to operating conditions of future fusion devices, however the brazing alloy and tantalum accumulate a large amount of deuterium in the case of the pressure above 100 Pa that leads to failure of the joint. The D retention after D plasma irradiation was substantial, but nearly independent on the fluence and the thickness of the W layer due to absorption from surrounding D2 gas.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
INTRODUCTION: The number of endovascular interventions performed on the arteries of the lower extremities is growing annually in the world, as they provide faster patient recovery and shorten the ...period of hospital stay. However, the development of restenosis of the reconstruction zone often leads to a need for repeated operations. AIM: To evaluate the effectiveness of combined antioxidant therapy in reducing the risk of restenosis after endovascular interventions. MATERIALS AND METHODS: The study included 84 patients with IIB–III stage peripheral arterial disease (PAD). Group A included 45 patients who underwent endovascular interventions, group B included 39 patients who were prescribed combined antioxidant therapy (Vitamin E, Actovegin®) a week before endovascular intervention and within a week after. On admission to hospital, in the first hours of stay, in 1, 7 days after surgery, the amount of Bax and platelet growth factor (PDGF BB) biomarkers were determined in the blood serum of all the patients. On control visits, the patients underwent duplex scanning of the arteries of the lower extremities to measure the thickness of the neointima and to detect restenosis of the intervention area. RESULTS: When comparing Bax values in the first hours and days after surgery in groups A and B, its growth was noted in patients of the first group (p < 0.01). At the same time, in patients of group A, the increase in PDGF BB was more pronounced (p < 0.01) on the 7th day. In patients of group A with restenosis of the reconstruction zone, the values of Bax marker in the first hours after surgery exceeded those in patients of group B (р < 0.01). On the 7th day, the amount of PDGF BB in these patients of group A was increased relative to group B (р < 0.01). The changes in the number and dynamics of the studied markers in group B patients with restenosis of the reconstruction zone led, firstly, to decrease in the percentage of stenosis in the area of the previous surgical intervention, secondly, to decrease in the severity of the clinical manifestation of this complication, thirdly, to occurrence of restenosis of the reconstruction zone in the later period, and, fourthly, to decrease in the percentage of patients with this complication. CONCLUSION: The use of combined antioxidant therapy targeted at the system of apoptosis, can reduce the thickness of the neointima of the reconstruction zone and reduce the percentage of patients with restenosis after endovascular interventions.
and
experimentation in the central nervous system are effective approaches to study its functioning. Manipulations
are characterized by easy experimental control and stable experimental conditions. ...However, transferring these advantages to
research remains technically and ethically challenging, preventing many research teams from acquiring critical recordings in their animal models. In order to transfer the benefits of
experimentation to
experimentation, we developed a suite of 3D-printed tools (a superfusion chamber with an independent brain presser and animal stand). Using the immature rat barrel cortex as a model, we show that our set of tools (further "superfusion preparation") provides stable conditions for electrophysiological and neuroimaging recordings in the neonatal rat neocortex
Highly correlated intracellular and extracellular activity was recorded during spontaneous and evoked cortical activity, supporting the possibility of simultaneous long-lasting electrophysiological recordings from a single cortical column
The optical intrinsic signal of evoked cortical responses was also recorded from the skull-free neocortex, suggesting the effective combination of the superfusion preparation with neuroimaging approaches. Modulation of immature activity by epicortical application of pharmacological agents via superfusion equally supports the use of the superfused cortex preparation in pharmacological screening. In addition to high efficiency (in affordability, reliability, and ease of use
), the 3D-printed set of tools developed should reduce animal use, supporting the 3Rs principle (Replacement, Reduction, and Refinement) of ethical use of animals.
Contemporary history of the Middle East has seen at least four periods of active inter-state alliance formation – three of which led by the United States. The return of Russia to the Middle East has ...helped shape new alliances and coalitions. Unlike the American “philosophy” of alliance formation underpinned by the imperative for a comprehensive politicomilitary presence as well as prevention of, first, Soviet and then, Iranian regional expansion, the Russian model is oriented toward the players, cooperation with which could solve a current or a potential crisis at a specific time period. Coupled with consistent and pragmatic foreign policy course, it was nontrivial strategies for flexible alliance-formation that enabled Moscow to establish itself as one of the leading player in the turbulent region as well as a responsible global power. At the same time, the comparative analysis of the Russian campaign in Syria and Moscow’s relations with key states in the region shows that Russia has been exercising elements of at least three alliance-formation strategies.
Alpha particles with energies on the order of megaelectronvolts will be the main source of plasma heating in future magnetic confinement fusion reactors. Instead of heating fuel ions, most of the ...energy of alpha particles is transferred to electrons in the plasma. Furthermore, alpha particles can also excite Alfvénic instabilities, which were previously considered to be detrimental to the performance of the fusion device. Here we report improved thermal ion confinement in the presence of megaelectronvolts ions and strong fast ion-driven Alfvénic instabilities in recent experiments on the Joint European Torus. Detailed transport analysis of these experiments reveals turbulence suppression through a complex multi-scale mechanism that generates large-scale zonal flows. This holds promise for more economical operation of fusion reactors with dominant alpha particle heating and ultimately cheaper fusion electricity.Experiments at the Joint European Torus tokamak show improved thermal ion confinement in the presence of highly energetic ions and Alfvénic instabilities in the plasma.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Abstract
Genetic resources of plants are the part of biological resources that includes plant material containing functional units of heredity, which has the actual or potential value for the ...breeding of plant varieties and hybrids. For the first time in the world, the need to collect genetic resources was justified by N.I. Vavilov. An important and urgent problem in plant breeding is the task of creation of breeding material with desired properties. The creation of such material is still a complex and, in some cases, difficult task. Plant diversity is preserved in the world’s collections and is an extremely valuable huge source of potentially useful genes that farmers and breeders need in order to develop higher yielding varieties that are better able to adapt to environmental conditions. Grain crops, such as wheat, barley, corn, rice, etc., are always considered as the most valuable agricultural crops in terms of fodder productive qualities and are the main food in many countries of the world. Consequently, the world gene pool of agricultural plants is an insurance policy for the further well-being of mankind.
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