Interaction of a supersonic, radiatively cooled plasma jet with an ambient medium

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Lactate Regulates Metabolic and Proinflammatory Circuits in Control of T Cell Migration and Effector Functions

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Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

Experimental study of shock waves from the interaction of a supersonic plasma jet with an ambient gas

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Interaction of a Supersonic Plasma Jet With an Argon Ambient Using Laser Interferometry

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Experimental studies of supersonic radiatively cooled plasma jets

Properties of radiatively cooled supersonic plasma jets formed by ablation of thin Al foils driven by 1.4 MA, 250 ns current pulse are presented. The jets are highly collimated with half-opening angles of ~2°. Measurements of the flow velocity (~60 km/s) and plasma temperature (~15 eV) in the jet with Thomson scattering diagnostic give internal Mach number of M ~ 3, suggesting additional collimation of the jet by toroidal magnetic fields

Jet-ambient interaction of a supersonic, radiatively-cooled jet in laboratory experiments

The formation of supersonic, radiatively cooled plasma jets with applications to laboratory astrophysics has been an active area of research on the MAGPIE generator. One of the ways of producing astrophysically-relevant jets in the laboratory is by using the ablation of plasma from a radial foil Z-pinch. In this configuration a ~1.4 MA, 250 ns current pulse is introduced into an aluminium disk with a thickness of 15 μm. The ablated plasma from the foil converges on the axis, producing a steady and collimated jet with a typical axial velocity of ~100 km/s. The setup allows for the addition of argon above the foil for jet-ambient interaction studies. The interaction is characterised by the formation of several shock features, which are presented and discussed from experimental data and numerical simulations

Rewards and Incentives for Nonsalaried Clinical Faculty Who Teach Medical Students

We surveyed the clerkship administrators of pediatrics, family medicine, and internal medicine at U.S. medical schools, and of pediatrics at Canadian medical schools to determine what rewards and incentives are being offered to nonsalaried faculty for office-based teaching. Monetary payment was offered by 13% to 22% of the programs. Nonmonetary rewards like educational opportunities were offered by 70% to 89%; academic appointments by 90% to 95%; special recognition events by 62% to 79%; and appreciation letters by 74% to 84% of programs. Only 3 of 338 responders offered no rewards or incentives