A Low-Dissipation Low-Dispersion Second-Order Scheme for Unstructured Finite-Volume Flow Solvers

A new low-dissipation low-dispersion second-order scheme suitable for unstructured finite-volume flow solvers is presented which is designed for vortical flows and for scale-resolving simulations of turbulence. The idea is that, by optimizing its dispersion properties, a standard second-order method can be improved significantly for such flows. The key is to include gradient in formation for computing face-values of the fluxes and to use this additional degree of freedom to improve the dispersion properties of the scheme. We motivate the scheme by a theoretical consideration of the dispersion properties for a one-dimensional scalar transport equation problem. Then the new scheme is applied using the DLR TAU-code for compressible flows and the DLR THETA-code for incompressible flows for simulations of the moving vortex problem and the Taylor-Green vortex flow. The improved accuracy for small scale transportation and the easy implementation make this scheme a promising candidate for efficient scale-resolving simulations of turbulent flows. Note: This paper is jointly published with a companion paper by Probst et al., where the low-dissipation low-dispersion 2nd-order scheme is applied to scale-resolving simulations of a channel flow, the backward-facing step flow, the flow around a rudimentary landing gear and around a 3-element airfoil near stall

Scale-Resolving Simulations with a Low-Dissipation Low-Dispersion Second-Order Scheme for Unstructured Finite-Volume Flow Solvers

A new low-dissipation low-dispersion 2nd-order scheme is applied to scale-resolving flow simulations using compressible and incompressible unstructured finite-volume solvers. In wall-resolved and wall-modeled LES computations of the channel flow the new scheme yields substantial improvements compared to the more dissipative/dispersive basic central scheme over a considerable range of Reynolds numbers. For general hy- brid RANS/LES simulations a numerical blending approach is applied which uses a local sensor function to switch between the new scheme in LES regions and the basic central scheme in the outer flow field. After an a-priori determination of a consistent sensor function, the hybrid numerical scheme is used to simulate a backward-facing step flow, where satisfactory results and reduced grid sensitivity are obtained. To demon- strate its potential in relevant aeronautical flows, the new scheme is successfully applied to hybrid RANS/LES computations of a 3-element airfoil near stall and a rudimentary landing gear with massive flow separation. Note that this paper is jointly published with a companion paper by Löwe et al., in which the low-dissipation low-dispersion 2nd-order scheme is derived and theoretically analyzed, followed by a basic assessment for fundamental numerical test cases

Scale-Resolving Simulations with a Low-Dissipation Low-Dispersion Second-Order Scheme for Unstructured Flow Solvers

A new low-dissipation low-dispersion second-order scheme is applied to scale-resolving flow simulations using compressible and incompressible unstructured finite volume solvers. In wall-resolved and wall-modeled large-eddy simulations of the plane channel flow, the new scheme yields substantial improvements compared to the more dissipative/dispersive standard central scheme over a considerable range of Reynolds numbers. For general hybrid Reynolds-averaged Navier Stokes/large-eddy simulations, a numerical blending approach is derived that uses a local sensor function to switch between the new scheme in the large-eddy simulation branch and the standard scheme in inviscid flow regions. After determining a suitable sensor formulation, the hybrid numerical scheme is applied to simulate a backward-facing step flow, for which satisfactory results and a reduced grid sensitivity are obtained. To demonstrate its potential in relevant aeronautical flows, the new scheme is successfully applied to hybrid Reynolds- averaged Navier Stokes/large-eddy simulations of a three-element airfoil near stall and a rudimentary landing gear with massive flow separation

VueBox® for quantitative analysis of contrast-enhanced ultrasound in liver tumors1

Dynamic contrast-enhanced ultrasound (DCE-US) enables quantification of tumor perfusion. VueBox (R) is a platform independent external software using DICOM cine loops which objectively provides various DCE-US parameters of tumor vascularity. This review summaries its use for diagnosis and treatment monitoring of liver tumors. The existing literature provides evidence on the successful application of Vuebox (R) based DCE-US for characterization and differential diagnosis of focal liver lesions, as well as on its use for monitoring of local ablative therapies and of modern systemic treatment in oncology

Intervention protocol: OPtimising thERapy to prevent avoidable hospital Admission in the Multi-morbid elderly (OPERAM): a structured medication review with support of a computerised decision support system.

Several approaches to medication optimisation by identifying drug-related problems in older people have been described. Although some interventions have shown reductions in drug-related problems (DRPs), evidence supporting the effectiveness of medication reviews on clinical and economic outcomes is lacking. Application of the STOPP/START (version 2) explicit screening tool for inappropriate prescribing has decreased inappropriate prescribing and significantly reduced adverse drug reactions (ADRs) and associated healthcare costs in older patients with multi-morbidity and polypharmacy. Therefore, application of STOPP/START criteria during a medication review is likely to be beneficial. Incorporation of explicit screening tools into clinical decision support systems (CDSS) has gained traction as a means to improve both quality and efficiency in the rather time-consuming medication review process. Although CDSS can generate more potential inappropriate medication recommendations, some of these have been shown to be less clinically relevant, resulting in alert fatigue. Moreover, explicit tools such as STOPP/START do not cover all relevant DRPs on an individual patient level. The OPERAM study aims to assess the impact of a structured drug review on the quality of pharmacotherapy in older people with multi-morbidity and polypharmacy. The aim of this paper is to describe the structured, multi-component intervention of the OPERAM trial and compare it with the approach in the comparator arm. This paper describes a multi-component intervention, integrating interventions that have demonstrated effectiveness in defining DRPs. The intervention involves a structured history-taking of medication (SHiM), a medication review according to the systemic tool to reduce inappropriate prescribing (STRIP) method, assisted by a clinical decision support system (STRIP Assistant, STRIPA) with integrated STOPP/START criteria (version 2), followed by shared decision-making with both patient and attending physician. The developed method integrates patient input, patient data, involvement from other healthcare professionals and CDSS-assistance into one structured intervention. The clinical and economical effectiveness of this experimental intervention will be evaluated in a cohort of hospitalised, older patients with multi-morbidity and polypharmacy in the multicentre, randomized controlled OPERAM trial (OPtimising thERapy to prevent Avoidable hospital admissions in the Multi-morbid elderly), which will be completed in the last quarter of 2019. Universal Trial Number: U1111-1181-9400 Clinicaltrials.gov: NCT02986425, Registered 08 December 2016. FOPH (Swiss national portal): SNCTP000002183. Netherlands Trial Register: NTR6012 (07-10-2016)

REACTIVE OXYGEN SPECIES АND ANTIOXIDANT SYSTEM ОF PLANTS

Under the influence of adverse conditions reactive oxygen species (ROS) are formed, which lead to oxidative stress. Increasing the ROS content in plants can pose a threat to the cells, causing lipid peroxidation, oxidative damage to proteins, nucleic acids, as well as inhibition of enzymes, activation of the pathway of programmed cell death, and ultimately leading to cell death. Plants have a well developed defense system to counteract active forms of oxygen (ROS), including both limiting the formation of ROS and neutralizing them. Under normal conditions, the formation and degradation of the ROS are in equilibrium. At the same time, under stress, the antioxidant system can not cope with its task

'Optimising PharmacoTherapy In the multimorbid elderly in primary CAre' (OPTICA) to improve medication appropriateness: study protocol of a cluster randomised controlled trial.

INTRODUCTION Multimorbidity and polypharmacy are major risk factors for potentially inappropriate prescribing (eg, overprescribing and underprescribing), and systematic medication reviews are complex and time consuming. In this trial, the investigators aim to determine if a systematic software-based medication review improves medication appropriateness more than standard care in older, multimorbid patients with polypharmacy. METHODS AND ANALYSIS Optimising PharmacoTherapy In the multimorbid elderly in primary CAre is a cluster randomised controlled trial that will include outpatients from the Swiss primary care setting, aged ≥65 years with ≥three chronic medical conditions and concurrent use of ≥five chronic medications. Patients treated by the same general practitioner (GP) constitute a cluster, and clusters are randomised 1:1 to either a standard care sham intervention, in which the GP discusses with the patient if the medication list is complete, or a systematic medication review intervention based on the use of the 'Systematic Tool to Reduce Inappropriate Prescribing'-Assistant (STRIPA). STRIPA is a web-based clinical decision support system that helps customise medication reviews. It is based on the validated 'Screening Tool of Older Person's Prescriptions' (STOPP) and 'Screening Tool to Alert doctors to Right Treatment' (START) criteria to detect potentially inappropriate prescribing. The trial's follow-up period is 12 months. Outcomes will be assessed at baseline, 6 and 12 months. The primary endpoint is medication appropriateness, as measured jointly by the change in the Medication Appropriateness Index (MAI) and Assessment of Underutilisation (AOU). Secondary endpoints include the degree of polypharmacy, overprescribing and underprescribing, the number of falls and fractures, quality of life, the amount of formal and informal care received by patients, survival, patients' quality adjusted life years, patients' medical costs, cost-effectiveness of the intervention, percentage of recommendations accepted by GPs, percentage of recommendation rejected by GPs and patients' willingness to have medications deprescribed. ETHICS AND DISSEMINATION The ethics committee of the canton of Bern in Switzerland approved the trial protocol. The results of this trial will be published in a peer-reviewed journal. MAIN FUNDING Swiss National Science Foundation, National Research Programme (NRP 74) 'Smarter Healthcare'. TRIAL REGISTRATION NUMBERS Clinicaltrials.gov (NCT03724539), KOFAM (Swiss national portal) (SNCTP000003060), Universal Trial Number (U1111-1226-8013)