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SARS-CoV-2 reinfection rate is low. The relative severity of the first and second episodes of infection remains poorly studied. In this study, we aimed at assessing the frequency of SARS-CoV-2 reinfections and comparing the severity of the first and second episodes of infection. We retrospectively included patients with SARS-CoV-2 positive RT-PCR at least 90 days after clinical recovery from a COVID-19 episode and with at least one negative RT-PCR after the first infection. Whole genome sequencing and variant-specific RT-PCR were performed and clinical symptoms and severity of infection were retrospectively documented from medical files. A total of 209 COVID-19 reinfected patients were identified, accounting for 0.4% of positive cases diagnosed from 19 March 2020 to 24 August 2021. Serology was performed in 64 patients, of whom 39 (60.1%) had antibodies against SARS-CoV-2 when sampled at the early stage of their second infection. Only seven patients (3.4%) were infected twice with the same variant. We observed no differences in clinical presentation, hospitalization rate, and transfer to ICU when comparing the two episodes of infections. Our results suggest that the severity of the second episode of COVID-19 is in the same range as that of the first infection, including patients with antibodies.

POLG‐related mitochondrial disease is a rare mitochondrial disorder that is potentially associated with anaesthetic complications such as propofol‐related infusion syndrome. A 19‐year‐old man with mitochondrial DNA deletions and POLG‐related disorders presented for an elective robotic Heller‐Dor myotomy for the treatment of oesophageal pseudo‐achalasia associated with severe gastro‐oesophageal reflux. The fasting period was minimised to reduce the risk of metabolic stress. The anaesthetic technique included a rapid sequence induction with propofol and rocuronium, a remifentanil and sevoflurane‐based general anaesthesia with multimodal monitoring and peri‐operative lactate‐free intravenous fluids with added dextrose. The patient did not experience propofol‐related infusion syndrome but did have delayed tracheal extubation due to residual neuromuscular blockade requiring a second dose of sugammadex. This report demonstrates the safety of single‐use, low‐dose propofol in this patient group. Patients with POLG‐related mitochondrial disease may be at risk of prolonged neuromuscular blockade, and appropriate dosing of neuromuscular blocking agents with monitoring of neuromuscular blockade is strongly encouraged.

The roll motion response of a single degree of freedom (SDOF) structural system to which a rigid rectangular partially filled liquid tank has been attached is considered. The SDOF structural system with the empty tank is first described with a mathematical model and this model is validated by performing decay experiments as well as experiments in which periodic excitations are applied to the system. The responses are accurately predicted by the model. The accuracy of these predictions allows us to study both experimentally and numerically, with weakly compressible SPH, the performance of the partially filled tank as a tuned liquid damper (TLD). The sloshing flows inside the tank comprise the onset of breaking waves which make the TLDs devices extremely difficult to model, especially for the potential flow multimodal approaches commonly used to simulate these sorts of coupled systems. In order to characterise the wave breaking effects on the response curves, tests have been performed with liquids of different viscosity, the increasing viscosity preventing the onset of breaking waves. The capabilities of SPH to treat this coupling problem are assessed and the results show that SPH is able to capture a substantial part of the physics involved in the addressed phenomena but further work remains still to be done relating to a more accurate treatment of the laminar viscosity and turbulence effects.

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The dependence on the Reynolds number of shallow depth sloshing flows inside rectangular tanks subjected to forced harmonic motion is studied in this paper with weaklycompressible SPH. We are interested in assessing the influence of viscous effects on the dynamics of shallow depth sloshing flows by using an SPH solver and by comparing with a Navier-Stokes level-set solver results. The goal of trying to model these viscous flows is compromised by the resolution requested due to their Reynolds number, if boundary layer effects are to be modeled. The convenience and feasibility of the implementation of free-slip and no-slip boundary conditions is also discussed.

Sloshing for low filling level resonant pitch motion is studied experimentally and numerically using SPH. Special attention is paid to the pressure fields on the tanks. Comparisons are made with experimental data and with Particle Finite Element Method (PFEM) calculations.