A User Study on Explainable Online Reinforcement Learning for Adaptive Systems

Online reinforcement learning (RL) is increasingly used for realizing adaptive systems in the presence of design time uncertainty. Online RL facilitates learning from actual operational data and thereby leverages feedback only available at runtime. However, Online RL requires the definition of an effective and correct reward function, which quantifies the feedback to the RL algorithm and thereby guides learning. With Deep RL gaining interest, the learned knowledge is no longer explicitly represented, but is represented as a neural network. For a human, it becomes practically impossible to relate the parametrization of the neural network to concrete RL decisions. Deep RL thus essentially appears as a black box, which severely limits the debugging of adaptive systems. We previously introduced the explainable RL technique XRL-DINE, which provides visual insights into why certain decisions were made at important time points. Here, we introduce an empirical user study involving 54 software engineers from academia and industry to assess (1) the performance of software engineers when performing different tasks using XRL-DINE and (2) the perceived usefulness and ease of use of XRL-DINE.Comment: arXiv admin note: substantial text overlap with arXiv:2210.0593

A thirteen-year analysis of Plasmodium falciparum populations reveals high conservation of the mutant pfcrt haplotype despite the withdrawal of chloroquine from national treatment guidelines in Gabon

<p>Abstract</p> <p>Background</p> <p>Chloroquine resistance (CR) decreased after the removal of chloroquine from national treatment guidelines in Malawi, Kenia and Tanzania. In this investigation the prevalence of the chloroquine resistance (CQR) conferring mutant <it>pfcrt </it>allele and its associated chromosomal haplotype were determined before and after the change in Gabonese national treatment guidelines from chloroquine (CQ) to artesunate plus amodiaquine (AQ) in 2003.</p> <p>Methods</p> <p>The prevalence of the wild type <it>pfcrt </it>allele was assessed in 144 isolates from the years 2005 - 07 by PCR fragment restriction digest and direct sequencing. For haplotype analysis of the chromosomal regions flanking the <it>pfcrt </it>locus, microsatellite analysis was done on a total of 145 isolates obtained in 1995/96 (43 isolates), 2002 (47 isolates) and 2005 - 07 (55 isolates).</p> <p>Results</p> <p>The prevalence of the mutant <it>pfcrt </it>allele decreased from 100% in the years 1995/96 and 2002 to 97% in 2005 - 07. Haplotype analysis showed that in 1995/96 79% of the isolates carried the same microsatellite alleles in a chromosomal fragment spanning 39 kb surrounding the <it>pfcrt </it>locus. In 2002 and 2005 - 07 the prevalence of this haplotype was 62% and 58%, respectively. <it>Pfcrt </it>haplotype analysis showed that all wild type alleles were CVMNK.</p> <p>Conclusion</p> <p>Four years after the withdrawal of CQ from national treatment guidelines the prevalence of the mutant <it>pfcrt </it>allele remains at 97%. The data suggest that the combination of artesunate plus AQ may result in continued selection for the mutant <it>pfcrt </it>haplotype even after discontinuance of CQ usage.</p

Impact of Right Ventricular Performance in Patients Undergoing Extracorporeal Membrane Oxygenation Following Cardiac Surgery

Background: Extracorporeal membrane oxygenation following cardiac surgery safeguards end‐organ oxygenation but unfavorably alters cardiac hemodynamics. Along with the detrimental effects of cardiac surgery to the right heart, this might impact outcome, particularly in patients with preexisting right ventricular (RV) dysfunction. We sought to determine the prognostic impact of RV function and to improve established risk‐prediction models in this vulnerable patient cohort. Methods and Results: Of 240 patients undergoing extracorporeal membrane oxygenation support following cardiac surgery, 111 had echocardiographic examinations at our institution before implantation of extracorporeal membrane oxygenation and were thus included. Median age was 67 years (interquartile range 60‐74), and 74 patients were male. During a median follow‐up of 27 months (interquartile range 16‐63), 75 patients died. Fifty‐one patients died within 30 days, 75 during long‐term follow‐up (median follow‐up 27 months, minimum 5 months, maximum 125 months). Metrics of RV function were the strongest predictors of outcome, even stronger than left ventricular function (P<0.001 for receiver operating characteristics comparisons). Specifically, RV free‐wall strain was a powerful predictor univariately and after adjustment for clinical variables, Simplified Acute Physiology Score‐3, tricuspid regurgitation, surgery type and duration with adjusted hazard ratios of 0.41 (95%CI 0.24‐0.68; P=0.001) for 30‐day mortality and 0.48 (95%CI 0.33‐0.71; P<0.001) for long‐term mortality for a 1‐SD (SD=−6%) change in RV free‐wall strain. Combined assessment of the additive EuroSCORE and RV free‐wall strain improved risk classification by a net reclassification improvement of 57% for 30‐day mortality (P=0.01) and 56% for long‐term mortality (P=0.02) compared with the additive EuroSCORE alone. Conclusions: RV function is strongly linked to mortality, even after adjustment for baseline variables and clinical risk scores. RV performance improves established risk prediction models for short‐ and long‐term mortality

The history of attention deficit hyperactivity disorder

The contemporary concept of attention deficit hyperactivity disorder (ADHD) as defined in the DSM-IV-TR (American Psychiatric Association 2000) is relatively new. Excessive hyperactive, inattentive, and impulsive children have been described in the literature since the nineteenth century. Some of the early depictions and etiological theories of hyperactivity were similar to current descriptions of ADHD. Detailed studies of the behavior of hyperactive children and increasing knowledge of brain function have changed the concepts of the fundamental behavioral and neuropathological deficits underlying the disorder. This article presents an overview of the conceptual history of modern-day ADHD

Krankenversicherung der Rentner: gesetzliche Grundlagen und Erlaeuterungen

SIGLEAvailable from Bibliothek des Instituts fuer Weltwirtschaft, ZBW, Duesternbrook Weg 120, D-24105 Kiel A 186628 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

A data protection focused adaptation engine for distributed video analytics pipelines

The design, development, deployment, and operation of a distributed Video Analytics Pipeline (VAP) at the edge of the network is highly complex. In the domain of adaptive systems, several solutions are proposed in literature to optimize either one particular performance aspect of a VAP, e.g., execution time or latency, or focus on minimal energy consumption, or calculate a trade-off including some of those aspects. However, nowadays, most systems utilizing a VAP that records personally identifiable data have to adhere to some form of data protection regulation, such as the GDPR. Still, adaptations to increase data protection requirements are often second to previously mentioned performance or energy consumption characteristics of a VAP. While there is state of the art literature dealing with data protection related adaptations, most of them solely focus on increasing certain security or privacy aspects of a system, leaving previously mentioned performance or energy consumption characteristics out of scope. To the best of our knowledge, there is no solution that covers all of these aspects. In this paper, we present a data protection focused adaptation engine that leverages the application- and infrastructure based adaptation space of a distributed VAP. The engine employs an extended system model and adaptation rules that are based on previous research. It features an optimization algorithm to improve data protection, performance and energy consumption characteristics of a distributed VAP.This work was supported by the European Union’s Horizon 2020 Research and Innovation Program (FogProtect) under Grant 871525. The authors acknowledge TU Wien Bibliothek for financial support through its Open Access Funding Programme