Model of mechanism behavior for verification of PLC programs

More extensive work on formal methods is now available for checking PLC (Programmable Logic Controller) programs. To verify a PLC program, it is necessary to consider a set of properties to prove and one of the most interesting problems that the designers must deal is to deduce a set of properties that traduces all the safety requirements of the system behavior. In this paper, we explore the contribution of such a plant model within the context of deduction, in a systematized way, of a set of properties to prove, verifying the PLC program. Our study is primarily experimental in nature and based on a case study. A set of properties to be checked based on detailed plant model is proposed. We then analyze how a Symbolic Model-Checking tool (the NuSMV has been selected) ensures verification of these properties either with or without the considered plant model

La caméline, une plante modèle pour la recherche translationnelle

National audienceEn biologie végétale, la recherche translationnelle vise à accélérer la valorisation de découvertes scientifiques réalisées à partir de plantes modèles au bénéfice de plantes d’intérêt agronomique. Dans ce domaine, la caméline est un outil particulièrement efficace : génétiquement proche de l’espèce modèle Arabidopsis thaliana, elle permet d’évaluer simplement de nouveaux caractères associés aux plantes oléoprotéagineuses

Towards a reasoned 1-D river model calibration

Le calage de modèle reste une étape critique de la modélisation numérique. Après de nombreuses tentatives d`automatisation de cette tâche dans différentes domaines liés à l`eau, des questions se posent encore sur la nécessité de caler des modèles à base physique. Cet article propose aux utilisateurs de codes de calcul en hydraulique un cadre pour réaliser cette tâche selon un « code de bonnes pratiques ». Ce cadre comporte une formalisation des objets manipulés en hydraulique fluviale 1-D ainsi qu`une description conceptuelle générique du processus de calage. Ces deux éléments ont été implémentés dans un système à base de connaissances, intégrant un code de calcul ainsi que des connaissances d`experts sur le calage de modèle. Un prototype de système d`assistance au calage a ensuite été construit à l`aide d`un code de calcul résolvant les équations de Saint-Venant dans des rivières à lit fixe. Le cadre fourni pour le calage de modèle est composé de trois niveaux indépendants reliés respectivement à la tâche générique, au domaine d`application, et au code de calcul lui-même. Les deux premiers niveaux de connaissances peuvent ainsi aisément être réutilisés pour construire des systèmes d`assistance au calage pour d`autres domaines d`application, comme l`hydraulique 2-D ou encore la modélisation hydrologique à base physique. / Model calibration remains a critical step in numerical modelling. After many attempts to automate this task in water-related domains, questions about the actual need for calibrating physics-based models are still open. This article proposes a framework for good model calibration practice for end-users of 1-D hydraulic simulation codes. This framework includes a formalisation of objects used in 1-D river hydraulics along with a generic conceptual description of the model calibration process. It was implemented within a knowledge-based system integrating a simulation code and expert knowledge about model calibration. A prototype calibration support system was then built up with a specific simulation code solving subcritical unsteady flow equations for fixed-bed rivers. The framework for model calibration is composed of three independent levels related respectively to the generic task, to the application domain, and to the simulation code itself. The first two knowledge levels can thus easily be reused to build calibration support systems for other application domains, like 2-D hydrodynamics or physics-based rainfall-runoff modelling

River model calibration, from guidelines to operational support tools

Numerical modelling is now used routinely to make predictions about the behaviour of environmental systems. Model calibration remains a critical step in the modelling process and different approaches have been taken to develop guidelines to support engineers and scientists in this task. This article reviews currently available guidelines for a river hydraulics modeller by dividing them into three types: on the calibration process, on hydraulic parameters, and on the use of hydraulic simulation codes. The article then presents an integration of selected guidelines within a knowledge-based calibration support system. A prototype called CaRMA-1 (Calibration of River Model Assistant) has been developed for supporting the calibration of models based on a specific 1D code. Two case studies illustrate the ability of the prototype to face operational situations in river hydraulics engineering, for which both data quality and quantity are not sufficient for an optimal calibration. Using CaRMA-1 allows the modeller to achieve the calibration task in accordance with good calibration practice implemented in the knowledge base. Relevant reasoning rules can easily be added to the knowledge base to extend the prototype range of applications. This study thus provides a framework for building operational support tools from various types of existing engineering guidelines

Residential exposure to solar ultraviolet radiation and incidence of childhood hematological malignancies in France

Few studies have investigated the relationship between solar ultraviolet radiation (UV) and childhood hematological malignancies (CHM). This study addresses the associations between residential UV exposure at diagnosis and the incidence of types and subtypes of CHM, by age and gender, in France, over a long period, on the fine scale of the 36,326 Communes that constitute mainland France. The 9,082 cases of acute leukemia and 3,563 cases of lymphoma diagnosed before the age of 15 years from 1990 to 2009 were provided by the French National Registry of Childhood Hematological Malignancies. The incidence of CHM was calculated by Commune, year, age and gender and expressed as the standardized incidence ratio (SIR). UV data from 1988 to 2007 were extracted from the EUROSUN database. The annual daily average UV exposure of the children ranged from 85.5 to 137.8 J/cm2. For each additional 25 J/cm2, there was a significant increase in precursor B-cell acute lymphoblastic leukemia (PBC-ALL) in children aged less than 5 years (SIR 1.18; 95 % CI 1.10–1.27). Further analysis of PBC-ALL in the young children suggested a better fit of models with a threshold, with the risk increasing above 100 J/cm2, for which the SIR was 1.24 (95 % CI 1.14–1.36) for a 25 J/cm2 increase. The results remained stable in analyses stratifying by deprivation index or degree of urbanization of the Communes. The study suggests that higher residential UV exposure may be positively associated with a higher incidence of PBC-ALL in early childhood

Mechanical characterization and comparison of different NiTi/silicone rubber interfaces

International audienceThis paper investigates the effects of different surface treatments on the mechanical resistance of interface between wires of NiTi shape memory alloy and silicone rubber. Three different treatments were used; primer, plasma and combination of both. The wires deoxidation effects have also been studied. In order to characterize the interface properties in such composite material, pull-out tests were carried out by means of a home-made device. This test allows us to evaluate the mechanical resistance of the interface in terms of the maximum force reached during the test. First, results show that the debonding force is not higher after the wires deoxidation. This preparation is therefore not necessary. Second, using a primer PM820 and plasma separately leads to a significant improvment of the mechanical resistance. Third, the combination of these treatments (primer followed by plasma) and a longer time of exposure to the plasma alone get the debonding force higher. Consequently, NiTi/silicone rubber interface improved only by means of plasma offers a new way to obtain biocompatible interfaces in such composite material

Involvement of Arabidopsis BIG protein in cell death mediated by Myo- Inositol homeostasis

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PUCHI regulates very long chain fatty acid biosynthesis during lateral root and callus formation

© 2019 National Academy of Sciences. All rights reserved. Lateral root organogenesis plays an essential role in elaborating plant root system architecture. In Arabidopsis, the AP2 family transcription factor PUCHI controls cell proliferation in lateral root primordia. To identify potential targets of PUCHI, we analyzed a time course transcriptomic dataset of lateral root formation. We report that multiple genes coding for very long chain fatty acid (VLCFA) biosynthesis enzymes are induced during lateral root development in a PUCHI-dependent manner. Significantly, several mutants perturbed in VLCFA biosynthesis show similar lateral root developmental defects as puchi-1. Moreover, puchi-1 roots display the same disorganized callus formation phenotype as VLCFA biosynthesis-deficient mutants when grown on auxin-rich callus-inducing medium. Lipidomic profiling of puchi-1 roots revealed reduced VLCFA content compared with WT. We conclude that PUCHI-regulated VLCFA biosynthesis is part of a pathway controlling cell proliferation during lateral root and callus formation

The potential of integrative phenomics to harness underutilized crops for improving stress resilience

The current agricultural and food system faces diverse and increasing challenges. These include feeding an ever-growing human population, expected to reach about 10 billion by 2050 combined with societal disruption, and the need to cope with the impact of climate change (FAO, 2022). Given that future environmental conditions will limit crop productivity (Zhao et al., 2017; Cooper et al., 2021) and the limited potential to continually increase the performance of staple crops by conventional breeding (Hickey et al., 2019), there is an urgent need to transform agricultural systems

N-Acyl Homoserine Lactones in Diverse Pectobacterium and Dickeya Plant Pathogens: Diversity, Abundance, and Involvement in Virulence

Soft-rot bacteria Pectobacterium and Dickeya use N-acyl homoserine lactones (NAHSLs) as diffusible signals for coordinating quorum sensing communication. The production of NAHSLs was investigated in a set of reference strains and recently-collected isolates, which belong to six species and share the ability to infect the potato host plant. All the pathogens produced different NAHSLs, among which the 3-oxo-hexanoyl- and the 3-oxo-octanoyl-l-homoserine lactones represent at least 90% of total produced NAHSL-amounts. The level of NAHSLs varied from 0.6 to 2 pg/cfu. The involvement of NAHSLs in tuber maceration was investigated by electroporating a quorum quenching vector in each of the bacterial pathogen strains. All the NAHSL-lactonase expressing strains produced a lower amount of NAHSLs as compared to those harboring the empty vector. Moreover, all except Dickeya dadantii 3937 induced a lower level of symptoms in potato tuber assay. Noticeably, aggressiveness appeared to be independent of both nature and amount of produced signals. This work highlights that quorum sensing similarly contributed to virulence in most of the tested Pectobacterium and Dickeya, even the strains had been isolated recently or during the past decades. Thus, these key regulatory-molecules appear as credible targets for developing anti-virulence strategies against these plant pathogens