A Case Study for Reversible Computing: Reversible Debugging of Concurrent Programs

International audienceReversible computing allows one to run programs not only in the usual forward direction, but also backward. A main application area for reversible computing is debugging, where one can use reversibility to go backward from a visible misbehaviour towards the bug causing it. While reversible debugging of sequential systems is well understood, reversible debugging of concurrent and distributed systems is less settled. We present here two approaches for debugging concurrent programs, one based on backtracking, which undoes actions in reverse order of execution, and one based on causal consistency, which allows one to undo any action provided that its consequences, if any, are undone beforehand. The first approach tackles an imperative language with shared memory, while the second one considers a core of the functional message-passing language Erlang. Both the approaches are based on solid formal foundations

TOOLympics 2019: An Overview of Competitions in Formal Methods

Evaluation of scientific contributions can be done in many different ways. For the various research communities working on the verification of systems (software, hardware, or the underlying involved mechanisms), it is important to bring together the community and to compare the state of the art, in order to identify progress of and new challenges in the research area. Competitions are a suitable way to do that. The first verification competition was created in 1992 (SAT competition), shortly followed by the CASC competition in 1996. Since the year 2000, the number of dedicated verification competitions is steadily increasing. Many of these events now happen regularly, gathering researchers that would like to understand how well their research prototypes work in practice. Scientific results have to be reproducible, and powerful computers are becoming cheaper and cheaper, thus, these competitions are becoming an important means for advancing research in verification technology. TOOLympics 2019 is an event to celebrate the achievements of the various competitions, and to understand their commonalities and differences. This volume is dedicated to the presentation of the 16 competitions that joined TOOLympics as part of the celebration of the 25th anniversary of the TACAS conference

Alterations of the podocyte proteome in response to high glucose concentrations

Diabetic nephropathy is one of the most common complications of diabetes mellitus and the leading cause of end-stage renal disease. A reduction in podocyte number has been documented in the kidneys of these patients. To identify the molecular changes in podocytes that are primarily caused by high glucose (HG) concentrations and not by secondary alterations (e.g. glomerular hypertension), we investigated the protein expression profiles in a podocyte cell line under long-term HG exposure (30 versus 10 mM for 2 wk). Proteins were separated by 2-DE, and we identified 39 different proteins in 48 spots that were differentially regulated by more than twofold in response to HG concentrations using MALDI-TOF MS and MASCOT software. These proteins belong to several protein classes, including cytoskeletal proteins and specific annexins (annexins III and VI). Downregulation of annexins III and VI by HG concentrations was confirmed by qRT-PCR, Western blot, and immunostaining, and was also observed in glomeruli of kidney biopsies from patients with diabetic nephropathy. Our data demonstrate that HG concentrations per se are sufficient to strongly modify the protein expression profile of podocytes, the analysis of which contributes to the identification of novel targets involved in diabetic nephropathy

Beyond loop bounds : comparing annotation languages for worst-case execution time analysis

Worst-case execution time (WCET) analysis is concerned with computing a precise-as-possible bound for the maximum time the execution of a program can take. This information is indispensable for developing safety-critical real-time systems, e. g., in the avionics and automotive fields. Starting with the initial works of Chen, Mok, Puschner, Shaw, and others in the mid and late 1980s, WCET analysis turned into a well-established and vibrant field of research and development in academia and industry. The increasing number and diversity of hardware and software platforms and the ongoing rapid technological advancement became drivers for the development of a wide array of distinct methods and tools for WCET analysis. The precision, generality, and efficiency of these methods and tools depend much on the expressiveness and usability of the annotation languages that are used to describe feasible and infeasible program paths. In this article we survey the annotation languages which we consider formative for the field. By investigating and comparing their individual strengths and limitations with respect to a set of pivotal criteria, we provide a coherent overview of the state of the art. Identifying open issues, we encourage further research. This way, our approach is orthogonal and complementary to a recent approach of Wilhelm et al. who provide a thorough survey of WCET analysis methods and tools that have been developed and used in academia and industry.Peer reviewedFinal Published versio

RABIOPRED, AN INNOVATIVE THERAGNOSTIC TOOL FOR PRECISION MEDICINE IN RHEUMATOID ARTHRITIS PATIENTS

Pathophysiology and treatment of rheumatic disease