To study the efficacy of lopinavir-ritonavir and hydroxychloroquine in critically ill patients with coronavirus disease 2019 .Methods: Critically ill adults with COVID-19 were randomized to receive lopinavir-ritonavir, hydroxychloroquine, combination therapy of lopinavir-ritonavir and hydroxychloroquine or no antiviral therapy (control). The primary endpoint was an ordinal scale of organ support-free days. Analyses used a Bayesian cumulative logistic model and expressed treatment effects as an adjusted odds ratio (OR) where an OR > 1 is favorable. Results:We randomized 694 patients to receive lopinavir-ritonavir (n = 255), hydroxychloroquine (n = 50), combination therapy (n = 27) or control (n = 362). The median organ support-free days among patients in lopinavir-ritonavir, hydroxychloroquine, and combination therapy groups was 4 (-1 to 15), 0 (-1 to 9) and-1 (-1 to 7), respectively,
The first inertial confinement fusion implosion experiments with equimolar deuterium-tritium thermonuclear fuel have been performed on the National Ignition Facility. These experiments use 0.17 mg of fuel with the potential for ignition and significant fusion yield conditions. The thermonuclear fuel has been fielded as a cryogenic layer on the inside of a spherical plastic capsule that is mounted in the center of a cylindrical gold hohlraum. Heating the hohlraum with 192 laser beams for a total laser energy of 1.6 mega joules produces a soft x-ray field with 300 eV temperature. The ablation pressure produced by the radiation field compresses the initially 2.2-mm diameter capsule by a factor of 30 to a spherical dense fuel shell that surrounds a central hot-spot plasma of 50 µm diameter. While an extensive set of x-ray and neutron diagnostics has been applied to characterize hot spot formation from the x-ray emission and 14.1 MeV deuterium-tritium primary fusion neutrons, thermonuclear fuel assembly is studied by measuring the down-scattered neutrons with energies in the range of 10 to 12 MeV. X-ray and neutron imaging of the compressed core and fuel indicate a fuel thickness of (14 ± 3) µm, which combined with magnetic recoil spectrometer measurements of the fuel areal density of (1 ± 0.09) g cm −2 result in fuel densities approaching 600 g cm −3 . The fuel surrounds a hot-spot plasma with average ion temperatures of (3.5 ± 0.1) keV that is measured with neutron time of flight spectra. Absolute neutron yields of (7.5 ± 0.1) × 10 14 have been recorded from the magnetic recoil spectrometer and nuclear activation diagnostics while gamma ray measurements provide the duration of nuclear activity of (170 ± 30) ps. These indirect-drive implosions result in the highest areal densities and neutron yields achieved on laser facilities to date. This achievement is the result of the first hohlraum and capsule tuning experiments where the stagnation pressures have been systematically increased by more than a factor of 10 by fielding low-entropy implosions through the control of radiation symmetry, small hot electron production, and proper shock timing. The stagnation pressure is above 100 Gbar resulting in high Lawson confinement parameters of P τ 10 atm s. Comparisons with radiation-hydrodynamic simulations indicate that the pressure is within a factor of three required for reaching ignition and high yield. This will be the focus of future higher-velocity implosions that will employ additional optimizations of hohlraum, capsule and laser pulse shape conditions.
A central feature of an inertial fusion energy (IFE) power plant is a target that has been compressed and heated to fusion conditions by the energy input of the driver. This is true whether the driver is a laser system, heavy ion beams or Z-pinch system. The IFE target fabrication, injection and tracking programmes are focusing on methods that will scale to mass production. We are working closely with target designers, and power plant systems specialists, to make specifications and material selections that will satisfy a wide range of required and desirable target characteristics. One-of-a-kind capsules produced for today's inertial confinement fusion experiments are estimated to cost about US$2500 each. Design studies of cost-effective power production from laser and heavy-ion driven IFE have suggested a cost goal of about $0.25-0.30 for each injected target (corresponding to ∼10% of the 'electricity value' in a target). While a four orders of magnitude cost reduction may seem at first to be nearly impossible, there are many factors that suggest this is achievable. This paper summarizes the design, specifications, requirements and proposed manufacturing processes for the future for laser fusion, heavy ion fusion and Z-pinch driven targets. These target manufacturing processes have been developed-and are proposed-based on the unique materials science and technology programmes that are ongoing for each of the target concepts. We describe the paradigm shifts in target manufacturing methodologies that will be needed to achieve orders of magnitude reductions in target costs, and summarize the results of 'nth-of-a-kind' plant layouts and cost estimates for future IFE power plant fuelling. These engineering studies estimate the cost of the target supply in a fusion economy, and show that costs are within the range of commercial feasibility for electricity production.
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