Rule Formats for Nominal Process Calculi

Publisher's version (útgefin grein)The nominal transition systems (NTSs) of Parrow et al. describe the operational semantics of nominal process calculi. We study NTSs in terms of the nominal residual transition systems (NRTSs) that we introduce. We provide rule formats for the specifications of NRTSs that ensure that the associated NRTS is an NTS and apply them to the operational specifications of the early and late pi-calculus. We also explore alternative specifications of the NTSs in which we allow residuals of abstraction sort, and introduce translations between the systems with and without residuals of abstraction sort. Our study stems from the Nominal SOS of Cimini et al. and from earlier works in nominal sets and nominal logic by Gabbay, Pitts and their collaborators.Research partially supported by the project Nominal SOS (nr. 141558-051) of the Icelandic Research Fund, the project 001-ABEL-CM-2013 within the NILS Science and Sustainability Programme, the Spanish Projects TRACES (TIN2015-67522-C3-3-R) and Bosco (PGC2018-102210-B-I00), and by Comunidad de Madrid as part of the program S2018/TCS-4339 (BLOQUES-CM) co-funded by EIE Funds of the European Union, and the projects RACCOON (H2020-EU 714729) and MATHADOR (COGS 724.464) of the European Research Council, and the Spanish addition to MATHADOR (TIN2016-81699-ERC)."Peer Reviewed

Towards a Declarative Language for Parallel and Concurrent Programming

We define a new language Eden by extending a functional language by constructs for the explicit specification of dynamic process systems. Concurrent systems can be classified either as transformational or reactive. For modelling the class of transformational systems, the introduction of a function-like abstraction mechanism is sufficient. In addition to this, the extra-functional concepts predefined nondeterministic processes and dynamic reply channels make the definition of reactive systems possible. The former construct is used to handle time-dependencies. The latter, which is similar to the incomplete message principle from concurrent logic programming, is a powerful mechanism for the treatment of dynamically specified communication channels. 1 Introduction Most parallel programming languages used nowadays are based on the imperative programming paradigm. In such languages, synchronization and communication between processes must be handled by the programmer at a low level of abst..

Evaluation of a quality improvement intervention to reduce anastomotic leak following right colectomy (EAGLE): pragmatic, batched stepped-wedge, cluster-randomized trial in 64 countries

Background Anastomotic leak affects 8 per cent of patients after right colectomy with a 10-fold increased risk of postoperative death. The EAGLE study aimed to develop and test whether an international, standardized quality improvement intervention could reduce anastomotic leaks. Methods The internationally intended protocol, iteratively co-developed by a multistage Delphi process, comprised an online educational module introducing risk stratification, an intraoperative checklist, and harmonized surgical techniques. Clusters (hospital teams) were randomized to one of three arms with varied sequences of intervention/data collection by a derived stepped-wedge batch design (at least 18 hospital teams per batch). Patients were blinded to the study allocation. Low- and middle-income country enrolment was encouraged. The primary outcome (assessed by intention to treat) was anastomotic leak rate, and subgroup analyses by module completion (at least 80 per cent of surgeons, high engagement; less than 50 per cent, low engagement) were preplanned. Results A total 355 hospital teams registered, with 332 from 64 countries (39.2 per cent low and middle income) included in the final analysis. The online modules were completed by half of the surgeons (2143 of 4411). The primary analysis included 3039 of the 3268 patients recruited (206 patients had no anastomosis and 23 were lost to follow-up), with anastomotic leaks arising before and after the intervention in 10.1 and 9.6 per cent respectively (adjusted OR 0.87, 95 per cent c.i. 0.59 to 1.30; P = 0.498). The proportion of surgeons completing the educational modules was an influence: the leak rate decreased from 12.2 per cent (61 of 500) before intervention to 5.1 per cent (24 of 473) after intervention in high-engagement centres (adjusted OR 0.36, 0.20 to 0.64; P < 0.001), but this was not observed in low-engagement hospitals (8.3 per cent (59 of 714) and 13.8 per cent (61 of 443) respectively; adjusted OR 2.09, 1.31 to 3.31). Conclusion Completion of globally available digital training by engaged teams can alter anastomotic leak rates. Registration number: NCT04270721 (http://www.clinicaltrials.gov)