10 research outputs found

    The MetNet vehicle : a lander to deploy environmental stations for local and global investigations of Mars

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    Investigations of global and related local phenomena on Mars such as atmospheric circulation patterns, boundary layer phenomena, water, dust and climatological cycles and investigations of the planetary interior would benefit from simultaneous, distributed in situ measurements. Practically, such an observation network would require low-mass landers, with a high packing density, so a large number of landers could be delivered to Mars with the minimum number of launchers. The Mars Network Lander (MetNet Lander; MNL), a small semi-hard lander/penetrator design with a payload mass fraction of approximately 17 %, has been developed, tested and prototyped. The MNL features an innovative Entry, Descent and Landing System (EDLS) that is based on inflatable structures. The EDLS is capable of decelerating the lander from interplanetary transfer trajectories down to a surface impact speed of 50-70 ms(-1) with a deceleration of <500 g for <20 ms. The total mass of the prototype design is approximate to 24 kg, with approximate to 4 kg of mass available for the payload. The EDLS is designed to orient the penetrator for a vertical impact. As the payload bay will be embedded in the surface materials, the bay's temperature excursions will be much less than if it were fully exposed on the Martian surface, allowing a reduction in the amount of thermal insulation and savings on mass. The MNL is well suited for delivering meteorological and atmospheric instruments to the Martian surface. The payload concept also enables the use of other environmental instruments. The small size and low mass of a MNL makes it ideally suited for piggy-backing on larger spacecraft. MNLs are designed primarily for use as surface networks but could also be used as pathfinders for high-value landed missions.Peer reviewe

    Development of thin-layer apparatus for separation of suspension with slime discharge unit

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    Subject of investigation: separation of finely dispersed suspension in the mining and metallurgical industries. The work develops a three-zone mathematical model of the suspension motion in an inclined channel. The speed of particles movement in the inclined channel was measured for the first time with the use of a laser anemometer with fibre light guides. The dependence of the intensification of the mass transfer upon the angle of the channel inclination and degree of dispersion of the gas phase was obtained for the first time. A pilot industrial apparatus was developed and tested. It features uniform discharge of the slime by the expenditure and density. Manufactured is a pilot lot of industrial thin-layer apparatus and compressive pumpsAvailable from VNTIC / VNTIC - Scientific & Technical Information Centre of RussiaSIGLERURussian Federatio

    Development of the mathematical model of fuel equipment and justification for diagnosing diesel engines by injector needle displacement

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    This article discusses the proposed method for diagnosing diesel fuel equipment. An analysis of available methods for diagnosing fuel equipment has been carried out. The authors describe their method for diagnosing plunger pairs of a highpressure fuel pump according to the parameter of displacement of the injector needle. The design of the diagnostic device for measuring the movement of the injector needle has been developed and patented. The dependence of the maximum displacement of the injector needle on the increase, due to wear, of the radial clearance of the plunger bushing at the minimum steady state of idling of the engine has been determined. The technique of diagnosing the technical condition of plunger pairs of a high-pressure fuel pump by injector needle displacement is considered in detail

    Notch, BMP and WNT/\u3b2-catenin network is impaired in endothelial cells of the patients with thoracic aortic aneurysm

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    Cellular and molecular mechanisms of thoracic aortic aneurysm are still not clear and therapeutic approaches are mostly absent. The role of endothelial cells in aortic wall integrity is emerging from recent studies. Although Notch pathway ensures endothelial development and integrity, and NOTCH1 mutations have been associated with thoracic aortic aneurysms, the role of this pathway in aneurysm remains elusive. The purpose of the present work was to study functions of Notch genes in endothelial cells of patients with sporadic thoracic aortic aneurysm.Aortic endothelial cells were isolated from aortic tissue of patients with thoracic aortic aneurysm and healthy donors. Gene expression of Notch and related BMP and WNT/beta-catenin pathways was estimated by qPCR; WNT/beta-catenin signaling was studied by TCF-luciferase reporter. To study the stress-response the cells were subjected to laminar shear stress and the expression of corresponding genes was estimated by qPCR.Analyses of mRNA expression of Notch genes, Notch target genes and Notch related pathways showed that endothelial cells of aneurysm patients have dysregulated Notch/BMP/WNT pathways compared to donor cells. Activity of Wnt pathway was significantly elevated in endothelial cells of the patients. Cells from patients had attenuated activation of DLL4, SNAIL1, DKK1 and BMP2 in response to shear stress.In conclusion endothelial cells of the patients with thoracic aortic aneurysm have dysregulated Notch, BMP and WNT/beta-catenin related signaling. Shear stress-response and cross-talk between Notch and Wnt pathways that normally ensures aortic integrity and resistance of endothelial cells to stress is impaired in aneurysmal patients. (c) 2018 Elsevier B.V. All rights reserved
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