Changes in Antioxidant Enzymes Activity and Oxidative Damage in Four Argania spinosa Ecotypes Under Water Stress Conditions

_Argania spinosa_ L. Skell, a tree endemic of Morocco, grows in semiarid and arid areas. Biochemical response to drought in four ecotypes of the _A. spinosa_ was compared. Choice of ecotypes was based on evident differences in geographical features in south-west Morocco: two coastal ecotypes (Essaouira and Agadir) and two paralittorale ecotypes (Aoulouz and Lakhssas). Lipid peroxidation (malonyldialdehyde (MDA)), content of endogenous hydrogen peroxide (H2O2) and antioxidant enzyme system (Catalase (CAT), Ascorbate peroxidase (APX), Total peroxidase (POD) and Polyphenoloxidase (PPO) were measured in control (100% relative humidity (RH) at field capacity (FC)) and water-stressed plants (50 and 25% RH at FC). For all ecotypes, drought stress significantly increased the contents of MDA and H2O2 and an ecotype effect was noted. According Two-way ANOVA analysis, the ecotype x watering regime interaction was highly significant. We found an increase in the activities of the four ROS-scavenging enzymes and an ecotype effect was noted. Ecotype x watering regime interaction shows that only the CAT and APX activities were significant. Highest values of POD and PPO activities were found in both paralittorale ecotypes. Increase in antioxidant enzyme activities appears to be an adaptive response to restore the reactive oxygen species in their homeostasis. The four study ecotypes were separated by two discriminant functions obtained by canonical discriminant analysis. Coastal ecotypes are separated from the paralittorale ecotypes mainly by POD and PPO activities and MDA content

Conceptual Architecture for Agent-Based Modelling of Supplier Selection Conducted by a Supply Chain Dyad

Within the fourth stage of industrialization, artificial intelligence and in particular the multi-agent systems paradigm is highly adopted. Within the agent approach, the industrial resources are defined as intelligent agents that negotiate with each other to implement dynamic reconfiguration and reach agility and higher customer satisfaction. In this paper a smart configuration of the agent-based system for multi-product dyadic supplier selection is proposed. The objective is to select suppliers for multiple products simultaneously in a vertical collaboration context while involving the customer of the purchasing company and considering its preferences. Negotiation experiments are conducted for initial validation of the proposed conceptual architecture

Advanced supplier selection: A hybrid multi-agent negotiation protocol supporting supply chain dyadic collaboration

This paper proposes a novel form of supplier selection involving the supply chain dyad as the buyer and the suppliers as sellers. The main proposed contribution is a multi-attribute decision hybrid protocol for supplier selection based on collaboration and negotiation, adapted to dyadic collaboration in a supply chain context. Suppliers and the purchasing dyad can reach an agreement on the details of the products simultaneously and exploit the preferences of the customer dyadic partner to enlarge the criteria choices of the products. For this, the proposed protocol combines a one-to-one bilateral dyadic collaboration protocol inside the purchasing dyad along with a one-to-many multi-bilateral bargaining protocol between the purchasing dyad and suppliers. Illustrative multi-agent simulation experiments were carried out to prove the effectiveness of the proposed protocol. The protocol implementation shows better negotiation results than the classic supplier selection process, along with expected higher customer partner satisfaction and a more embedded dyadic relationship

Electrolyte ions and glutathione enzymes as stress markers in Argania spinosa subjected to drought stress and recovery

Understanding the mechanisms underlying Argania spinosa responses to drought stress is essential for its regeneration and domestication. Toward that end, an integrative study of tolerance responses to drought stress in four A. spinosa ecotypes (2 contrasting coastal ecotypes (Adm and Rab) and 2 contrasting inland ecotypes (Alz and Lks)) have been conducted. Responses to soil drying and re -watering were measured at physiological and biochemical levels. Soil drying resulted in significant increase in leaf concentrations of potassium (K+), calcium (Ca2+) and magnesium (Mg2+) with differential responses between ecotypes. The glutathione-related enzymes: glutathione peroxidase (GP), glutathione reductase (GR) and glutathione S-transferase (GST) showed a significant increase in their enzymatic activity in A. spinosa plants subjected to drought stress. Additionally, a significant increase in thiol protein content in the four ecotypes was recorded, during drought stress. These antioxidant traits responded differently depending on ecotype. However, rapid and significant changes in the studied physiological and biochemical traits were observed during recovery from drought, only after four days. According to the traits having the most discriminating power, the both inland ecotypes, especially Lks ecotype, seem to be potential candidates for regeneration of argan forest and their domestication in arid and semi-arid environments.Key words: Argania spinosa, drought stress, glutathione enzymes, thiol compounds, recovery

Contribution à l'étude des manipulateurs répondants et flexibles

Le présent mémoire traite de la simulation et de l'analyse cinématique et dynamique des systèmes mécaniques articulés avec des applications au cas de la robotique. Notre premier chapitre qui est une introduction à notre travail, présente l'état actuel des connaissances sur ce sujet, et parmi les différentes possibilités de choix que tous avons, on procédera par élimination pour ne garder que la partie qui nous intéresse tout en précisant la terminologie qui va être utilisée. Ce chapitre parle de l'architecture des systèmes mécaniques articulés, de la notion de redondance, de l'efficacité des logiciels, de l'écriture automatique des équations, des différents aspects de la cinématique, de l'introduction de la flexibilité et de la résolution des équations dynamiques des corps déformables. Les chapitres 2, 3, 4, 5 sont consacrés à la modélisation géométrique et cinématique des systèmes mécaniques avec des applications aux robots manipulateurs. Dans le chapitre de la modélisation géométrique, un logiciel est présenté pour écrire de façon automatique les équations littérales du modèle. Quant à la modélisation cinématique, les problèmes relatifs à la redondance sont posés et des solutions sont apportées pour éviter les obstacles et les singularités. Nous y verrons aussi le côté cinématique des équations de mouvement d'un système dynamique contraint. Les chapitres 6, 7, 8, 9 traitent de la dynamique des corps flexibles. On y verra toutes les étapes de la construction du modèle mathématique, avec la spécificité du choix judicieux des coordonnées qui localisent chaque corps dans le référentiel. Ce choix facilitera la commande des moteurs dans le cas des robots manipulateurs. On y verra aussi les méthodes retenues pour la résolution des équations dynamiques et les exemples d'applications seront traités. Le dernier chapitre sera une synthèse de l'ensemble du travail et on y présentera des suggestions pour continuer sur d'autres aspects de ce travail

Contribution à l'étude des manipulateurs répondants et flexibles

Le présent mémoire traite de la simulation et de l'analyse cinématique et dynamique des systèmes mécaniques articulés avec des applications au cas de la robotique. Notre premier chapitre qui est une introduction à notre travail, présente l'état actuel des connaissances sur ce sujet, et parmi les différentes possibilités de choix que tous avons, on procédera par élimination pour ne garder que la partie qui nous intéresse tout en précisant la terminologie qui va être utilisée. Ce chapitre parle de l'architecture des systèmes mécaniques articulés, de la notion de redondance, de l'efficacité des logiciels, de l'écriture automatique des équations, des différents aspects de la cinématique, de l'introduction de la flexibilité et de la résolution des équations dynamiques des corps déformables. Les chapitres 2, 3, 4, 5 sont consacrés à la modélisation géométrique et cinématique des systèmes mécaniques avec des applications aux robots manipulateurs. Dans le chapitre de la modélisation géométrique, un logiciel est présenté pour écrire de façon automatique les équations littérales du modèle. Quant à la modélisation cinématique, les problèmes relatifs à la redondance sont posés et des solutions sont apportées pour éviter les obstacles et les singularités. Nous y verrons aussi le côté cinématique des équations de mouvement d'un système dynamique contraint. Les chapitres 6, 7, 8, 9 traitent de la dynamique des corps flexibles. On y verra toutes les étapes de la construction du modèle mathématique, avec la spécificité du choix judicieux des coordonnées qui localisent chaque corps dans le référentiel. Ce choix facilitera la commande des moteurs dans le cas des robots manipulateurs. On y verra aussi les méthodes retenues pour la résolution des équations dynamiques et les exemples d'applications seront traités. Le dernier chapitre sera une synthèse de l'ensemble du travail et on y présentera des suggestions pour continuer sur d'autres aspects de ce travail

Analysis of drivers’ errors at roundabouts in Morocco

Roundabouts have increased in a significant way in recent years in Moroccan cities as they have been seen as a solution to congestion problems and traffic safety issues. However, roundabouts are relatively new to Moroccan drivers and the rules of priority to which the users are accustomed are reversed in roundabouts. This can lead to confusion and misleading. The overall objective of this study is to identify roundabout features that appear to play a role in the difficulties that drivers encounter when crossing roundabouts. This paper will present a comprehensive understanding of what is required of drivers when crossing roundabouts. We then predict failures that can occur at roundabout using our driver error taxonomy. A case study of two roundabouts in Morocco is analyzed as illustration. The paper concludes with implications of the findings to future design

A cognitive and metacognitive approach for exploring link between urban transport environment and driver behaviour: case of roundabout crossed by tramway line

The proliferation of roundabouts and tramway lines are among the most spectacular transformations of Moroccan roads and landscapes in recent years. These changes raise serious concerns about the effects of these new urban and road developments on traffic, on drivers’ behaviours, and thus on road safety. These issues brin g up the question concerning the adequacy bet ween the choices of road designers and the expectations of road users. Indeed, sustainable ur ban transport and well f unctioning road cannot be designed without a holistic understanding of the way drivers act in changing environment through which they move in time and space. Consequently, there is a strong need to further knowledge about practices and behaviours of road users. The present research investigates the cognitive and metacognitive strategies use by drivers in a complex t echnical system such as roundabo ut crossed by tramway line. In this article we propose an empirical model to explore the effect of urban transport environment on drivers’ behaviours. The paper presents an exploratory study based on a data triangulation app roach including database analysis, interview, observation, and think aloud protocol. The paper presents the main findings of the study and discusses their implications for road safety