Applying model transformation and Event-B for specifying an industrial DSL

In this paper we describe our experience in applying the Event-B formalism for specifying the dynamic semantics of a real-life industrial DSL. The main objective of this work is to enable the industrial use of the broad spectrum of specification analysis tools that support Event-B. To leverage the usage of Event-B and its analysis techniques we developed model transformations, that allowed for automatic generation of Event-B specifications of the DSL programs. The model transformations implement a modular approach for specifying the semantics of the DSL and, therefore, improve scalability of the specifications and the reuse of their verification. Keywords: domain specific language, Event-B, model transformations, verification and validation, reuse, scalabilit

How to think about informal proofs

This document is the Accepted Manuscript version of the following article: Brendan Larvor, ‘How to think about informal proofs’, Synthese, Vol. 187(2): 715-730, first published online 9 September 2011. The final publication is available at Springer via doi:10.1007/s11229-011-0007-5It is argued in this study that (i) progress in the philosophy of mathematical practice requires a general positive account of informal proof; (ii) the best candidate is to think of informal proofs as arguments that depend on their matter as well as their logical form; (iii) articulating the dependency of informal inferences on their content requires a redefinition of logic as the general study of inferential actions; (iv) it is a decisive advantage of this conception of logic that it accommodates the many mathematical proofs that include actions on objects other than propositions; (v) this conception of logic permits the articulation of project-sized tasks for the philosophy of mathematical practice, thereby supplying a partial characterisation of normal research in the fieldPeer reviewedFinal Accepted Versio

Visualization of formal specifications for understanding and debugging an industrial DSL

In this work we report on our proof of concept of a generic approach: visualized formal specification of a Domain Specific Language (DSL) can be used for debugging, understanding, and impact analysis of the DSL programs. In our case study we provide a domain-specific visualization for the Event-B specification of a real-life industrial DSL and perform a user study among DSL engineers to discover opportunities for its application. In this paper, we explain the rationale behind our visualization design, discuss the technical challenges of its realization and how these challenges were solved using the Model Driven Engineering (MDE) techniques. Based on the positive feedback of the user study, we present our vision on how this successful experience can be reused and the approach can be generalized for other DSLs

Distinct structural plasticity in the hippocampus and amygdala of the middle-aged common marmoset (Callithrix jacchus)

Adult neurogenesis in the primate brain is generally accepted to occur primarily in two specific areas; the subgranular zone (SGZ) of the hippocampal dentate gyrus (DG) and the subventricular zone (SVZ) of the lateral ventricles. Hippocampal neurogenesis is well known to be downregulated by stress and aging in rodents, however there is less evidence documenting the sensitivity of neuroblasts generated in the SVZ. In primates, migrating cells generated in the SVZ travel via a unique temporal stream (TS) to the amygdala and entorhinal cortex. Using adult common marmoset monkeys (Callithrix jacchus), we examined whether i) adult-generated cells in the marmoset amygdala differentiate into doublecortin-positive (DCX+) neuroblasts, and ii) whether lasting changes occur in DCX-expressing cells in the DG or amygdala when animals are exposed to 2 weeks of psychosocial stress. A surprisingly large population of DCX+ immature neurons was found in the amygdala of these 4-year-old monkeys with an average density of 163,000 DCX+ cells per mm(3). Co-labeling of these highly clustered cells with PSA-NCAM supports that a subpopulation of these cells are migratory and participate in chain-migration from the SVZ to the amygdala in middle-aged marmosets. Exposure to 2 weeks of isolation and social defeat stress failed to alter the numbers of BrdU+, or DCX+ cells in the hippocampus or amygdala when evaluated 2 weeks after psychosocial stress, indicating that the current stress paradigm has no long-term consequences on neurogenesis in this primate

Applying model transformation and Event-B for specifying an industrial DSL

In this paper we describe our experience in applying the Event-B formalism for specifying the dynamic semantics of a real-life industrial DSL. The main objective of this work is to enable the industrial use of the broad spectrum of specification analysis tools that support Event-B. To leverage the usage of Event-B and its analysis techniques we developed model transformations, that allowed for automatic generation of Event-B specifications of the DSL programs. The model transformations implement a modular approach for specifying the semantics of the DSL and, therefore, improve scalability of the specifications and the reuse of their verification. Keywords: domain specific language, Event-B, model transformations, verification and validation, reuse, scalabilit

Island grammar-based parsing using GLL and Tom

Extending a language by embedding within it another language presents significant parsing challenges, especially if the embedding is recursive. The composite grammar is likely to be nondeterministic as a result of tokens that are valid in both the host and the embedded language. In this paper we examine the challenges of embedding the Tom language into a variety of general-purpose high level languages. Tom provides syntax and semantics for advanced pattern matching and tree rewriting facilities. Embedded Tom constructs are translated into the host language by a preprocessor, the output of which is a composite program written purely in the host language. Tom implementations exist for Java, C, C#, Python and Caml. The current parser is complex and difficult to maintain. In this paper, we describe how Tom can be parsed using island grammars implemented with the Generalised LL (GLL) parsing algorithm. The grammar is, as might be expected, ambiguous. Extracting the correct derivation relies on our disambiguation strategy which is based on pattern matching within the parse forest. We describe different classes of ambiguity and propose patterns for resolving them

Diaphragm muscle fiber weakness and ubiquitin-proteasome activation in critically ill patients

Contains fulltext : 155008.pdf (publisher's version ) (Closed access)RATIONALE: The clinical significance of diaphragm weakness in critically ill patients is evident: it prolongs ventilator dependency, and increases morbidity and duration of hospital stay. To date, the nature of diaphragm weakness and its underlying pathophysiologic mechanisms are poorly understood. OBJECTIVES: We hypothesized that diaphragm muscle fibers of mechanically ventilated critically ill patients display atrophy and contractile weakness, and that the ubiquitin-proteasome pathway is activated in the diaphragm. METHODS: We obtained diaphragm muscle biopsies from 22 critically ill patients who received mechanical ventilation before surgery and compared these with biopsies obtained from patients during thoracic surgery for resection of a suspected early lung malignancy (control subjects). In a proof-of-concept study in a muscle-specific ring finger protein-1 (MuRF-1) knockout mouse model, we evaluated the role of the ubiquitin-proteasome pathway in the development of contractile weakness during mechanical ventilation. MEASUREMENTS AND MAIN RESULTS: Both slow- and fast-twitch diaphragm muscle fibers of critically ill patients had approximately 25% smaller cross-sectional area, and had contractile force reduced by half or more. Markers of the ubiquitin-proteasome pathway were significantly up-regulated in the diaphragm of critically ill patients. Finally, MuRF-1 knockout mice were protected against the development of diaphragm contractile weakness during mechanical ventilation. CONCLUSIONS: These findings show that diaphragm muscle fibers of critically ill patients display atrophy and severe contractile weakness, and in the diaphragm of critically ill patients the ubiquitin-proteasome pathway is activated. This study provides rationale for the development of treatment strategies that target the contractility of diaphragm fibers to facilitate weaning