Adjoint-Based Error Estimation and Mesh Adaptation for Hybridized Discontinuous Galerkin Methods

We present a robust and efficient target-based mesh adaptation methodology, building on hybridized discontinuous Galerkin schemes for (nonlinear) convection-diffusion problems, including the compressible Euler and Navier-Stokes equations. Hybridization of finite element discretizations has the main advantage, that the resulting set of algebraic equations has globally coupled degrees of freedom only on the skeleton of the computational mesh. Consequently, solving for these degrees of freedom involves the solution of a potentially much smaller system. This not only reduces storage requirements, but also allows for a faster solution with iterative solvers. The mesh adaptation is driven by an error estimate obtained via a discrete adjoint approach. Furthermore, the computed target functional can be corrected with this error estimate to obtain an even more accurate value. The aim of this paper is twofold: Firstly, to show the superiority of adjoint-based mesh adaptation over uniform and residual-based mesh refinement, and secondly to investigate the efficiency of the global error estimate

A Comparison of Hybridized and Standard DG Methods for Target-Based hp-Adaptive Simulation of Compressible Flow

We present a comparison between hybridized and non-hybridized discontinuous Galerkin methods in the context of target-based hp-adaptation for compressible flow problems. The aim is to provide a critical assessment of the computational efficiency of hybridized DG methods. Hybridization of finite element discretizations has the main advantage, that the resulting set of algebraic equations has globally coupled degrees of freedom only on the skeleton of the computational mesh. Consequently, solving for these degrees of freedom involves the solution of a potentially much smaller system. This not only reduces storage requirements, but also allows for a faster solution with iterative solvers. Using a discrete-adjoint approach, sensitivities with respect to output functionals are computed to drive the adaptation. From the error distribution given by the adjoint-based error estimator, h- or p-refinement is chosen based on the smoothness of the solution which can be quantified by properly-chosen smoothness indicators. Numerical results are shown for subsonic, transonic, and supersonic flow around the NACA0012 airfoil. hp-adaptation proves to be superior to pure h-adaptation if discontinuous or singular flow features are involved. In all cases, a higher polynomial degree turns out to be beneficial. We show that for polynomial degree of approximation p=2 and higher, and for a broad range of test cases, HDG performs better than DG in terms of runtime and memory requirements

RobotKube: Orchestrating Large-Scale Cooperative Multi-Robot Systems with Kubernetes and ROS

Modern cyber-physical systems (CPS) such as Cooperative Intelligent Transport Systems (C-ITS) are increasingly defined by the software which operates these systems. In practice, microservice architectures can be employed, which may consist of containerized microservices running in a cluster comprised of robots and supporting infrastructure. These microservices need to be orchestrated dynamically according to ever changing requirements posed at the system. Additionally, these systems are embedded in DevOps processes aiming at continually updating and upgrading both the capabilities of CPS components and of the system as a whole. In this paper, we present RobotKube, an approach to orchestrating containerized microservices for large-scale cooperative multi-robot CPS based on Kubernetes. We describe how to automate the orchestration of software across a CPS, and include the possibility to monitor and selectively store relevant accruing data. In this context, we present two main components of such a system: an event detector capable of, e.g., requesting the deployment of additional applications, and an application manager capable of automatically configuring the required changes in the Kubernetes cluster. By combining the widely adopted Kubernetes platform with the Robot Operating System (ROS), we enable the use of standard tools and practices for developing, deploying, scaling, and monitoring microservices in C-ITS. We demonstrate and evaluate RobotKube in an exemplary and reproducible use case that we make publicly available at https://github.com/ika-rwth-aachen/robotkube .Comment: 7 pages, 2 figures, 2 tables; Accepted to be published as part of the 26th IEEE International Conference on Intelligent Transportation Systems (ITSC), Bilbao, Spain, September 24-28, 202

Digitale Selbstbestimmung

Die fortschreitende Digitalisierung verändert die Gesellschaft und viele Lebensbereiche grundlegend. Beachtlichen Nutzungspotenzialen der sich stetig weiterentwickelnden Sammlung, Auswertung und Verwendung von personenbezogenen Daten steht die Gefahr gegenüber, dass die Entscheidungs- und Handlungsfreiheit der Menschen eingeschränkt wird. Für Nutzer digitaler Medien wird es zunehmend schwieriger, selbstbestimmt zu handeln. Ein Konzept der „digitalen Selbstbestimmung“ sowie verwandte Begriffe wie etwa „digitale Autonomie“ werden daher in der öffentlichen und wissenschaftlichen Diskussion immer bedeutsamer. Es fehlt bisher jedoch ein ausgearbeitetes theoretisches Konzept, welches „digitale Selbstbestimmung“ als normativen Begriff klärt und empirische Bedingungen für die Möglichkeit digitaler Selbstbestimmung systematisiert. Ausgehend von der Leitfrage „Was ist ‚digitale Selbstbestimmung‘?“ wird in dieser Studie anhand einer explorativen Literaturrecherche und einer philosophischen Begriffsanalyse ein Konzept der digitalen Selbstbestimmung entwickelt. Dieses Konzept expliziert digitale Selbstbestimmung anhand der sieben Begriffskomponenten Kompetenz, Informiertheit, Werte, Wahlmöglichkeit, Freiwilligkeit, Willensbildung und Handlung. Darüber hinaus werden technische, soziokulturelle und personenbezogene Determinanten identifiziert, d.h. Bedingungen und Faktoren, welche empirisch mitbestimmen, inwieweit eine Person digital selbstbestimmt ist. Der empirische Teil der Studie stellt Erkenntnisse über die Einstellungen von deutschen Nutzerinnen und Nutzer hinsichtlich des Umgangs mit personenbezogenen Daten vor. Die repräsentative sozialwissenschaftliche Erhebung wurde mit Hilfe eines standardisierten Fragebogens durchgeführt, der auf der Basis des theoretischen Konzeptes entwickelt wurde. Es wird deutlich, dass die Sicherheit persönlicher Daten im Internet angezweifelt wird, dass die Möglichkeiten, sich über gespeicherte persönliche Daten und ihre Weitergabe zu informieren, als unzureichend beurteilt werden, und dass Nutzer sich eine stärkere Einflussnahme auf die Speicherung und Verwendung persönlicher Daten wünschen. Ein mittel- bis langfristiges Ziel der Studie ist es, die wissenschaftliche Erforschung von digitaler Selbstbestimmung zu stimulieren und letztlich zur Förderung digitaler Selbstbestimmung beizutragen

ECOG and BMI as preoperative risk factors for severe postoperative complications in ovarian cancer patients: results of a prospective study (RISC-GYN—trial)

Background: Accompanying co-morbidities in patients with ovarian cancer are of major relevance for scheduling debulking surgery, especially in the anesthesiological consultations. Aim of this study was to evaluate the impact of co-morbidities and patient characteristics on postoperative complications. Methods: Patients undergoing maximal cytoreductive surgery were prospectively enrolled from October 2015 to January 2017. Various variables were recorded, such as the Charlson comorbidity index, Eastern cooperative oncology group scale of performance status (ECOG PS) and the American society of anesthesiologists physical status classification system (ASA PS). Surgical complications were graded using the Clavien-Dindo criteria. Logistic regression models were used to analyze risk factors for severe postoperative complications. Results: Of 106 enrolled patients, 19 (17.9%) developed severe postoperative complications grade >= IIIb according to Clavien-Dindo criteria. In the multivariable regression analysis impaired (ECOG PS) > 1 (odds ratio OR) 13.34, 95% confidence interval (CI) 1.74-102.30, p = 0.01), body mass index (BMI) > 25 kg/m(2) (OR 10.48, 95% CI 2.38-46.02, p = 0.002) along with the use of intraoperative norepinephrine > 0.11 mu g/kg/min (OR 4.69, 95% CI 1.13-19.46, p = 0.03) and intraoperative fresh frozen plasma (FFP) > 17 units (OR 4.11, 95% CI 1.12-15.14, p = 0.03) appeared as significant predictors of severe postoperative complications. Conclusion: We demonstrated that neither the presence of a certain comorbidity nor the summation of the co-morbidities were associated with adverse outcome. Patient characteristics, such as ECOG PS > 1 and obesity (BMI > 25 kg/m(2)), are highly predictive factors for severe postoperative complications. The analysis of intraoperative data showed that the need for more than > 0.11 mu g/kg/min of norepinephrine and transfusions of FFPs more than 17 units were strongly associated with severe postoperative complications

Entwicklungen in der Pränataldiagnostik: verändertes Erleben der Schwangerschaft und Auswirkungen bei pathologischem fetalen Befund

'Die Weiterentwicklung der Pränataldiagnostik hat die Betreuung schwangerer Frauen stetig verändert, und auch von den Frauen wird eine Schwangerschaft heute völlig anders erlebt als noch vor wenigen Jahrzehnten. Trotz erheblicher Fortschritte in der medizinischen Versorgung sind aber noch längst nicht alle Erkrankungen des Kindes therapeutisch zu beeinflussen; insbesondere nach Feststellung einer genetisch bedingten Erkrankung oder Behinderung des Kindes stellt sich für die Frauen und ihre Partner oft die Frage danach, ob sie die Schwangerschaft fortsetzen können. Betroffene Frauen bzw. Paare reagieren auf solche Situationen nicht selten mit einer Schock-Reaktion, und auch langfristig können sich psychische Probleme einstellen, unabhängig davon, ob die Schwangerschaft ausgetragen oder wegen einer medizinischen Indikation gemäß Paragraf 218a Abs. 2 StGB abgebrochen wurde. Um die Betroffenen in einer solchen Krisensituation zu unterstützen und sie auch im Entscheidungsprozess zu begleiten wurde an drei Modellstandorten (Bonn, Düsseldorf und Essen) eine psychosoziale Beratung etabliert, wobei diese psychosoziale Beratung zusätzlich zur ärztlichen Beratung unabhängig von konfessioneller oder nicht-konfessioneller Ausrichtung ergebnisoffen erfolgt. Die wissenschaftliche Evaluation von insgesamt 512 Erstberatungen und die Verlaufsuntersuchung über zwei Jahre zeigte eine hohe Akzeptanz der Beratung von Seiten der Betroffenen. Viele Argumente sprechen dafür, eine solche Beratung als Regelangebot im Kontext von Pränatalmedizin zu etablieren.' (Autorenreferat)'The further development of prenatal diagnosis has led to changes in the care for pregnant women. Also, pregnant women nowadays experience pregnancy in a way very different from that a few decades ago. Despite of impressive medical progress, it is still not possible to have an therapeutic impact on all diseases of the foetus and the child. In particular, when a genetic disorder is diagnosed, the question arises whether or not the pregnancy should be continued. More often than not, women or couples, respectively, display a shock reaction following this disclosure. In the long run, psychological problems may evolve, regardless of the continuation of the pregnancy or its termination (abortion) on grounds of article 218a, 2 StGB (German Criminal Code) for medical reasons. For providing support to these women in crisis and for accompanying the decision-making process, psychosocial counselling has been established in three demonstration sites (Bonn, Düsseldorf and Essen). This counselling had been offered in addition to the medical counselling and has been performed in an unbiased manner, regardless of the denominational orientation of the responsible body. The assessment of 512 first-time counselling sessions as well as the accompanying two-year evaluation study show that this kind of counselling has been widely accepted by the affected women. There are striking arguments for establishing psychosocial counselling as a scheduled part of counselling in prenatal diagnosis.' (author's abstract)

Enhancing Lidar-based Object Detection in Adverse Weather using Offset Sequences in Time

Automated vehicles require an accurate perception of their surroundings for safe and efficient driving. Lidar-based object detection is a widely used method for environment perception, but its performance is significantly affected by adverse weather conditions such as rain and fog. In this work, we investigate various strategies for enhancing the robustness of lidar-based object detection by processing sequential data samples generated by lidar sensors. Our approaches leverage temporal information to improve a lidar object detection model, without the need for additional filtering or pre-processing steps. We compare $10$ different neural network architectures that process point cloud sequences including a novel augmentation strategy introducing a temporal offset between frames of a sequence during training and evaluate the effectiveness of all strategies on lidar point clouds under adverse weather conditions through experiments. Our research provides a comprehensive study of effective methods for mitigating the effects of adverse weather on the reliability of lidar-based object detection using sequential data that are evaluated using public datasets such as nuScenes, Dense, and the Canadian Adverse Driving Conditions Dataset. Our findings demonstrate that our novel method, involving temporal offset augmentation through randomized frame skipping in sequences, enhances object detection accuracy compared to both the baseline model (Pillar-based Object Detection) and no augmentation.Comment: Published as part of the III. International Conference on Electrical, Computer and Energy Technologies (ICECET 2023), Cape Town, South Africa, November 16-17, 202

Gender differences of health literacy in persons with a migration background: a systematic review and meta-analysis

Objective: To investigate gender differences of health literacy in individuals with a migration background. Design: Systematic review and meta-analysis. OVID/MEDLINE, PsycINFO and CINAHL were searched in March 2018 and July 2020. Setting: Studies had to provide health literacy data for adult women and men with a migration background, collected with a standardised instrument, or report results that demonstrated the collection of such data. Health literacy data were extracted from eligible studies or requested from the respective authors. Using a random-effects model, a meta-analysis was conducted to assess standardised mean differences (SMDs) of health literacy in men and women. Two researchers independently assessed risk of bias for each included study using the Appraisal Tool for Cross-Sectional Studies. Results: Twenty-four studies were included in this systematic review. Thereof, 22 studies (8012 female and 5380 male participants) were included in the meta-analyses. In six studies, gender-specific health literacy scores were reported. The authors of additional 15 studies provided their data upon request and for one further study data were available online. Women achieved higher health literacy scores than men: SMD=0.08, 95% CI 0.002 to 0.159, p=0.04, I2=65%. Another 27 studies reported data on female participants only and could not be included due to a lack of comparable studies with male participants only. Authors of 56 other eligible studies were asked for data, but without success. Conclusion Men with a migration background—while being much less frequently examined—may have lower health literacy than women. As heterogeneity between studies was high and the difference became statistically insignificant when excluding studies with a high risk of bias, this result must be interpreted with caution. There is a paucity of research on the social and relational aspects of gender in relation to health literacy among people with a migration background, especially for men

Case report: Variant-specific pre-exposure prophylaxis of SARS-CoV-2 infection in multiple sclerosis patients lacking vaccination responses

Sphingosine-1-phosphate receptor modulators and anti-CD20 treatment are widely used disease-modifying treatments for multiple sclerosis. Unfortunately, they may impair the patient’s ability to mount sufficient humoral and T-cellular responses to vaccination, which is of special relevance in the context of the SARS-CoV-2 pandemic. We present here a case series of six multiple sclerosis patients on treatment with sphingosine-1-phosphate receptor modulators who failed to develop SARS-CoV-2-specific antibodies and T-cells after three doses of vaccination. Due to their ongoing immunotherapy, lacking vaccination response, and additional risk factors, we offered them pre-exposure prophylactic treatment with monoclonal SARS-CoV-2-neutralizing antibodies. Initially, treatment was conducted with the antibody cocktail casirivimab/imdevimab. When the SARS-CoV-2 Omicron variant became predominant, we switched treatment to monoclonal antibody sotrovimab due to its sustained neutralizing ability also against the Omicron strain. Since sotrovimab was approved only for the treatment of COVID-19 infection and not for pre-exposure prophylaxis, we switched treatment to tixagevimab/cilgavimab as soon as it was granted marketing authorization in the European Union. This antibody cocktail has retained, albeit reduced, neutralizing activity against the Omicron variant and is approved for pre-exposure prophylaxis. No severe adverse events were recorded for our patients. One patient had a positive RT-PCR for SARS-CoV-2 under treatment with sotrovimab, but was asymptomatic. The other five patients did not develop symptoms of an upper respiratory tract infection or evidence of a SARS-CoV-2 infection during the time of treatment up until the finalization of this report. SARS-CoV-2-neutralizing antibody treatment should be considered individually for multiple sclerosis patients lacking adequate vaccination responses on account of their immunomodulatory treatment, especially in times of high incidences of SARS-CoV-2 infection