Search results for " Structural"
showing 10 items of 1751 documents
Large-Scale Recombinant Production of the SARS-CoV-2 Proteome for High-Throughput and Structural Biology Applications
2021
The highly infectious disease COVID-19 caused by the Betacoronavirus SARS-CoV-2 poses a severe threat to humanity and demands the redirection of scientific efforts and criteria to organized research projects. The international COVID19-NMR consortium seeks to provide such new approaches by gathering scientific expertise worldwide. In particular, making available viral proteins and RNAs will pave the way to understanding the SARS-CoV-2 molecular components in detail. The research in COVID19-NMR and the resources provided through the consortium are fully disclosed to accelerate access and exploitation. NMR investigations of the viral molecular components are designated to provide the essential…
Design and manufacturing feasibility of ITER TBM Frame and Dummy TBMs
2016
Abstract The operation and test of mock-ups of tritium breeding blankets relevant for a future commercial reactor is one of the goals of the ITER machine. To accomplish this goal, mock-ups of breeding blankets, called Test Blanket Modules (TBMs), are installed in three ITER equatorial ports. Each TBM and the associated shield form a TBM-set that is mechanically attached to a steel frame called TBM Frame. A Frame and two TBM-Sets form a TBM Port Plug (TBM PP). The ITER Organization is responsible for the design and manufacture of the TBM Frames and of the Dummy TBMs that could replace the TBM-sets in case they were not available. This paper describes the recent results of the design supporti…
Direct observation of frequency modulated transcription in single cells using light activation
2013
Single-cell analysis has revealed that transcription is dynamic and stochastic, but tools are lacking that can determine the mechanism operating at a single gene. Here we utilize single-molecule observations of RNA in fixed and living cells to develop a single-cell model of steroid-receptor mediated gene activation. We determine that steroids drive mRNA synthesis by frequency modulation of transcription. This digital behavior in single cells gives rise to the well-known analog dose response across the population. To test this model, we developed a light-activation technology to turn on a single steroid-responsive gene and follow dynamic synthesis of RNA from the activated locus. DOI: http:/…
Innovative straight formulation for plate in bending
2017
In this paper it has been introduced an innovative formulation for evaluating the deflection function of a simply supported plate loaded by uniformly distributed edge moments. Framed into Line Element-less Method, this formulation allows the evaluation of solution in terms of deflection, through few lines of algorithm implemented by Mathematica software without resorting to any discretization neither in the domain nor in the boundary. Interesting savings in terms of time and computational costs are achieved. Results obtained by the proposed method are well contrasted by ones obtained by classical methods and Finite Element Method.
Design optimization for the quench protection of DTT's superconducting toroidal field magnets
2021
Abstract The paper is focused on the optimal design of Fast Discharge Unit (FDU) for the quench protection of the Toroidal Field (TF) magnets of the Divertor Tokamak Test facility (DTT), an experimental facility under construction in ENEA Frascati Research Centre (Rome, Italy). The FDU is a safety key component that protects the superconducting magnets when a quench is detected through the fast extraction of the energy stored in the magnets by adding a discharge dump resistor (DR) in the TF magnets circuit. A comparison between a fixed DR and a switched variable DR has been implemented by changing resistor parameters and by using multiple current control of the power electronics components …
Hjelmslev et la "fonction sémiotique", du modèle structural au modèle cognitif
2008
The article discusses the concept of semiotics function in Hjelmslev, finding sources of the theory of language’s stratification. The semiotic function, which is in Hjelmslev the principle underlying the dynamic layering, is identified here as both an attraction of two heterogeneous spaces and as a set of operations of sense’s establishment. At historiographic level, this article presents a new hypothesis of interpretation, that the hjelmslevian structuralism has not built a static theory of language, disinterested to the cognitive dimension, but a careful theory to operational aspects of semiosis.
Gravitational flow of a thin film of liquid metal in a strong magnetic field
2014
Abstract The influence of a poloidal magnetic field of the spherical Tokamak on super thin (h ≈ 0.1 mm) film flow of liquid metal driven by gravity over the surface of the cooled divertor plate is addressed. The experimental setup developed at the Institute of Physics, University of Latvia (IPUL) is described, which makes it possible to drive and visualize such liquid metal flows in the solenoid of the superconducting magnet “Magdalena”. As applied to the above setup, the magnetic field effect on the operation of the capillary system of liquid metal flow distribution (CSFD) is evaluated by using molten metal (lithium or eutectic InGaSn alloy) with a very small linear flowrate q ≤ 1 mm2/s, s…
Characterization and thermomechanical assessment of a SiC-sandwich material for Flow Channel Inserts in DCLL blankets
2019
Abstract Flow Channel Inserts (FCIs) are key elements in the high-temperature Dual Coolant Lead Lithium (DCLL) blanket, since they insulate electrically the flowing PbLi to avoid MHD effects and protect the steel structure from the hot liquid metal. SiC-based materials are main candidates for high-temperature FCIs, being a dense-porous SiC-based sandwich material an attractive option. The present work is focused on the development of such a SiC-based material. On the one hand, in order to assess the suitability of the concept for FCIs, the main results of a stress analysis, MHD and heat transfer simulations are summarized. On the other hand, the experimental production of the SiC-based mate…
Thermal-hydraulic and thermo-mechanical simulations of Water-Heavy Liquid Metal interactions towards the DEMO WCLL breeding blanket design
2019
Abstract The Water-Cooled Lithium Lead breeding blanket concept foresees the eutectic lithium-lead (Pb-15.7Li) alloy being cooled by pressurized sub-cooled water (temperature 295–328 °C; pressure 15.5 MPa) flowing in double wall tubes. Therefore, the interaction between the Pb-15.7Li and water (e.g. tube rupture) represents one of the main safety concerns for the design and safety analysis. Available LIFUS5/Mod2 experimental data are employed to assess the performances of thermal-hydraulic and thermo-mechanic codes. Thermal-hydraulic simulations, by SIMMER-III code, are focused on the prediction of the thermodynamic interaction among the fluids. ABAQUS Finite Element code, used for the desi…
Progress in the benchmark exercise for analyzing the lithiate breeder pebble bed thermo-mechanical behaviour
2006
The Helium Cooled Pebble Bed (HCPB) Blanket is one of the reference concepts for the European Breeding Blanket Programme for DEMO. In the reference blanket module, alternate layers of lithiated ceramics and beryllium pebbles act, respectively, as tritium breeder and neutron multiplier. The thermo-mechanical behaviour of both the pebble beds and their performances in reactor relevant conditions are also dependent on the pebble size and cell geometries (bed thickness, pebble packing factor, bed thermal conductivity). Therefore, in the EU Fusion Technology Programme, several out-of-pile experimental test campaigns have been performed to determine these behaviours. Theoretical calculations have…