Association of Under-Approximation Techniques for Generating Tests from Models

International audienceIn this paper we present a Model-Based Testing approach with which we generate tests from an abstraction of a source behavioural model. We show a new algorithm that computes the abstraction as an under-approximation of the source model. Our first contribution is to combine two previous approaches proposed by Ball and Pasareanu et al. to compute May, Must+ and Must- abstract transition relations. Prooftechniques are used to compute these transition relations. The tests obtained by covering the abstract transitions have to be instantiated from the source model. So, following Pasareanu et al., our algorithm additionally computes a concrete transition relation: the tests obtained as sequences of concrete transitions need not be instantiated from the source model. Another contribution is to propose a choice of relevant paramaters and heuristics to pilot the tests computation. We experiment our approach and compare it with a previous approach of ours to compute tests from an abstraction that over-approximates the source model

High intake of sugars and starch, low number of meals and low roughage intake are associated with equine gastric ulcer syndrome in a Belgian cohort

Equine gastric ulcer syndrome (EGUS) is a pathological condition affecting the glandular and squamous regions of the stomach. It is characterized by non-specific clinical signs, behavioural changes or can also be found without any overt clinical manifestations. Nutritional factors such as intermittent feeding, high sugars and starch intake, large amounts of straw as forage and prolonged time without access to forage have all been associated with an increased risk of equine squamous gastric disease (ESGD). The aim of this study was to investigate which nutritional practices are commonly seen in clinical ESGD cases in Belgium. Medical records of 27 horses referred to the equine nutritional service at Ghent University (2013-2018) due to equine gastric ulcer lesions were reviewed. Twenty-one healthy horses referred for dietary evaluation during the same period were selected as control cases (CC). Dietary evaluation was performed on an individual basis. Forage/concentrate ratio on dry matter basis, forage content in the diet, total dietary sugars and starch intake per day and per meal were analysed. Retrospective descriptive and statistical analyses were performed. Significantly, higher amounts of forage intake (%DM per BW) in the CC vs. ESGD group were noted (p <= .05) with average values of 1.39 (SD +/- 0.27) and 1.27 (SD +/- 0.70) respectively. There were no significant differences for sugars and starch intake in g/kg BW/day (p = .18). However, the sugars and starch intake per meal (g/kg BW/meal) in the CC group (average value 1.06, SD +/- 0.56) was significantly (p < .001) lower than in the EGUS group (average value 1.85 SD +/- 0.78). Forage intake below the recommended absolute minimum value as well as high sugars and starch intake were most commonly associated with EGUS in the present case series. An adequate diet formulation taking into account these main nutritional factors is therefore essential to avoid gastric problems in horses

Review: Feeding conserved forage to horses: recent advances and recommendations

The horse is a non-ruminant herbivore adapted to eating plant-fibre or forage-based diets. Some horses are stabled for most or the majority of the day with limited or no access to fresh pasture and are fed preserved forage typically as hay or haylage and sometimes silage. This raises questions with respect to the quality and suitability of these preserved forages (considering production, nutritional content, digestibility as well as hygiene) and required quantities. Especially for performance horses, forage is often replaced with energy dense feedstuffs which can result in a reduction in the proportion of the diet that is forage based. This may adversely affect the health, welfare, behaviour and even performance of the horse. In the past 20 years a large body of research work has contributed to a better and deeper understanding of equine forage needs and the physiological and behavioural consequences if these are not met. Recent nutrient requirement systems have incorporated some, but not all, of this new knowledge into their recommendations. This review paper amalgamates recommendations based on the latest understanding in forage feeding for horses, defining forage types and preservation methods, hygienic quality, feed intake behaviour, typical nutrient composition, digestion and digestibility as well as health and performance implications. Based on this, consensual applied recommendations for feeding preserved forages are provided

High-starch diets alter equine faecal microbiota and increase behavioural reactivity

Gut microbiota have been associated with health, disease and behaviour in several species and are an important link in gut-brain axis communication. Diet plays a key role in affecting the composition of gut microbiota. In horses, high-starch diets alter the hindgut microbiota. High-starch diets are also associated with increased behavioural reactivity in horses. These changes in microbiota and behaviour may be associated. This study compares the faecal microbiota and behaviour of 10 naïve ponies. A cross-over design was used with experimental groups fed high-starch (HS) or high-fibre (HF) diets. Results showed that ponies were more reactive and less settled when being fed the HS diet compared to the HF diet. Irrespective of diet, the bacterial profile was dominated by two main phyla, Firmicutes, closely followed by Bacteroidetes. However, at lower taxonomic levels multivariate analysis of 16S rRNA gene sequencing data showed diet affected faecal microbial community structure. The abundance of 85 OTUs differed significantly related to diet. Correlative relationships exist between dietary induced alterations to faecal microbiota and behaviour. Results demonstrate a clear link between diet, faecal microbial community composition and behaviour. Dietary induced alterations to gut microbiota play a role in affecting the behaviour of the host

Parallelization Of An Algorithm Used To Simulate Atomic Force Microscope Images

. We present the parallelization of an algorithm used to simulate images obtained with an Atomic Force Microscope. We use the standard parallel programming environment PVM so that the parallelization be architecture independent. We propose different algorithms: with or without large transfers of data between master and slaves and with or without load balancing. We compare execution run times on three kinds of platform, namely networks of homogeneous or heterogeneous workstations, symmetric multiprocessors with shared memory and a massively parallel machine with distributed memory. For this specific problem, the use of PVM leads to a good speedup for all architectures. However, we also show that the best algorithm depends on the kind of architecture. In particular a load balancing strategy is important for efficiency on an heterogeneous platform, whereas it has only a small effect on the other platforms. 1 Introduction Physicists need ever increasing computation power to solve simulati..

Instrumentation of annotated c programs for test generation

Conference of 14th IEEE International Working Conference on Source Code Analysis and Manipulation, SCAM 2014 ; Conference Date: 28 September 2014 Through 29 September 2014; Conference Code:109634International audienceSoftware verification and validation often rely on formal specifications that encode desired program properties. Recent research proposed a combined verification approach in which a program can be incrementally verified using alternatively deductive verification and testing. Both techniques should use the same specification expressed in a unique specification language. This paper addresses this problem within the Frama-C framework for analysis of C programs, that offers ACSL as a common specification language. We provide a formal description of an automatic translation of ACSL annotations into C code that can be used by a test generation tool either to trigger and detect specification failures, or to gain confidence, or, under some assumptions, even to confirm that the code is in conformity with respect to the annotations. We implement the proposed specification translation in a combined verification tool Study. Our initial experiments suggest that the proposed support for a common specification language can be very helpful for combined static-dynamic analyses

Determination of the effective dose of Saccharomyces cerevisiae CBS 493.94 used as microbial additives for horses

International audienc