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International audience; Identification of native soil-derived Trichoderma spp. isolates and analysis of their antagonist traits against Lasiodiplodiatheobromae causing stem-end rot in papaya, Archives of Phytopathology and Plant Protection

International audience; Real-time event detection and targeted decision making for emerging mission-critical applications require systems that extract and process relevant data from IoT sources in smart spaces. Oftentimes, this data is heterogeneous in size, relevance, and urgency, which creates a challenge when considering that different groups of stakeholders (e.g., first responders, medical staff, government officials, etc) require such data to be delivered in a reliable and timely manner. Furthermore, in mission-critical settings, networks can become constrained due to lossy channels and failed components, which ultimately add to the complexity of the problem. In this paper, we propose PrioDeX, a cross-layer middleware system that enables timely and reliable delivery of mission-critical data from IoT sources to relevant consumers through the prioritization of messages. It integrates parameters at the application, network, and middleware layers into a data exchange service that accurately estimates end-to-end performance metrics through a queueing analytical model. PrioDeX proposes novel algorithms that utilize the results of this analysis to tune data exchange configurations (event priorities and dropping policies), which is necessary for satisfying situational awareness requirements and resource constraints. PrioDeX leverages Software-Defined Networking (SDN) methodologies to enforce these configurations in the IoT network infrastructure. We evaluate our approach using both simulated and prototype-based experiments in a smart building fire response scenario. Our application-aware prioritization algorithm improves the value of exchanged information by 36% when compared with no prioritization; the addition of our network-aware drop rate policies improves this performance by 42% over priorities only and by 94% over no prioritization.

Background There are few studies about the presence of murine typhus in Greece. Our objective was to conduct a large scale retrospective investigation to determine the clinical and epidemiological features of patients diagnosed with murine typhus in Greece. Methodology/Principal findings From 2012 to 2019 serum samples from hospitalized patients and outpatients throughout Greece suspected for murine typhus infection were tested by immunofluorescence assay for Rickettsia typhi. Immunofluorescence positive samples obtained since 2016 were also tested by qPCR targeting R. typhi. Clinical and epidemiological data were retrospectively collected for the patients with confirmed murine typhus. Overall, we tested 5,365 different patients and, in total, 174 patients from all geographic regions of Greece were diagnosed with murine typhus. The most frequently reported sign or symptom was fever (89%), followed by headache (84%) and rash (81%). The classical triad of fever, headache, and rash was present in 72% of patients during their illness. Severe infections with complications including acute renal failure or septic shock were not recorded. The majority of cases (81%) occurred during May–October and peaked in June and September. Most of patients (81%) infected in Athens, recalled that their only activity the last weeks before symptoms onset was swimming on the beach and 59% of them also reported an insect bite while sunbathing. Conclusions/Significance Our results may reflect the reemergence of murine typhus in Greece and we highlight the importance of awareness of this difficult-to-recognize undifferentiated febrile illness.

International audience; Table olives, the number one consumed fermented food in Europe, are widely consumed as they contain many valuable ingredients for health. It is also a food which may be the subject of adulteration, as many different olive varieties with different geographical origin, exist all over the word. In the present study, the image analysis of stones of six main Greek protected designation of origin (PDO) table olive varieties was performed for the control of their authentication and discrimination, with cv. Prasines Chalkidikis, cv. Kalamata Olive, cv. Konservolia Stylidas, cv. Konservolia Amfissis, cv. Throuba Thassos and cv. Throuba Chios being the studied olive varieties. Orthogonal partial least square discriminant analysis (OPLS-DA) was used for discrimination and classification of the six Greek table olive varieties. With a 98.33% of varietal discrimination, the OPLS-DA model proved to be an efficient tool to authentify table olive varieties from their morphological characteristics.

International audience; Internet of Things (IoT) aim to leverage data from multiple sensors, actuators and devices for improving peoples' daily life and safety. Multiple data sources must be integrated, analyzed from the corresponding application and notify interested stakeholders. To support the data exchange between data sources and stakeholders, the publish/subscribe (pub/sub) middleware is often employed. Pub/sub provides additional mechanisms such as reliable messaging, event dropping, prioritization, etc. The event dropping mechanism is often used to satisfy Quality of Service (QoS) requirements and ensure system stability. To enable event dropping, basic approaches apply finite buffers or data validity periods and more sophisticated ones are information-aware. In this paper, we introduce a pub/sub mechanism for probabilistic event dropping by considering the stakeholders' intermittent connectivity and QoS requirements. We model the pub/sub middleware as a network of queues which includes a novel ON/OFF queueing model that enables the definition of join probabilities. We validate our analytical model via simulation and compare our mechanism with existing ones. Experimental results can be used as insights for developing hybrid dropping mechanisms.

International audience; Real-time event detection and targeted decision making for emerging mission-critical applications, e.g. smart fire fighting, requires systems that extract and process relevant data from connected IoT devices in the environment. In this paper, we propose FireDeX, a cross-layer middleware that facilitates timely and effective exchange of data for coordinating emergency response activities. FireDeX adopts a publish-subscribe data exchange paradigm with brokers at the network edge to manage prioritized delivery of mission-critical data from IoT sources to relevant subscribers. It incorporates parameters at the application, network, and middleware layers into a data exchange service that accurately estimates end-to-end performance metrics (e.g. delays, success rates). We design an extensible queueing theoretic model that abstracts these cross-layer interactions as a network of queues, thereby making it amenable for rapid analysis. We propose novel algorithms that utilize results of this analysis to tune data exchange configurations (event priorities and dropping policies) while meeting situational awareness requirements and resource constraints. FireDeX leverages Software-Defined Networking (SDN) methodologies to enforce these configurations in the IoT network infrastructure. We evaluate its performance through simulated experiments in a smart building fire response scenario. Our results demonstrate significant improvement to mission-critical data delivery under a variety of conditions. Our application-aware prioritization algorithm improves the value of exchanged information by 36% when compared with no prioritization; the addition of our network-aware drop rate policies improves this performance by 42% over priorities only and by 94% over no prioritization.

International audience; Nowaday, the academic system is made up of paradoxes, and inconsistencies ; between the promoted discourses and pedagogical practices, and more and more in contradiction with the cooperative model, this article exposes and analyzes the praxis of academic professors / collective researchers at university. The setting up of a cooperative / institutional device constitutes the frame of these praxis mainly carried out at a Master level. The concept of emancipatory work relationship is one of the main theme for discussion. Projects management, setting up institutions within the group, reflexive and cooperative analysis of practices, cooperative / institutional pedagogy, cooperative techniques and development / transformation of the space-course, constitute the framework of these evidences.; Dans un système universitaire pétri de paradoxes, et d'incohérences entre les discours promus et les pratiques pédagogiques, et de plus en contradiction avec le modèle coopératif, cet article expose et analyse la praxis de quatre enseignants/chercheurs collectifs à l'université. La mise en place d'un dispositif coopératif/institutionnel constitue la trame de ces praxis menées pour la plupart au niveau Master. La notion de rapport de travail émancipateur est l'un des thèmes centraux de cet article. Conduite de projets, mise en place d'institutions au sein du groupe, analyse réflexive et coopérative de pratiques, pédagogie coopérative /institutionnelle, techniques coopératives et aménagement/transformation de l'espace-cours, constituent la trame de ces témoignages.

International audience; Internet of Things (IoT) applications consist of diverse Things (sensors and devices) in terms of hardware resources. Furthermore, such applications are characterized by the Things' mobility and multiple interaction types, such as synchronous, asynchronous, and streaming. Middleware IoT protocols consider the above limitations and support the development of effective applications by providing several Quality of Service features. These features aim to enable application developers to tune an application by switching different levels of response times and delivery success rates. However, the profusion of the developed IoT protocols and the intermittent connectivity of mobile Things, result to a non-trivial application tuning. In this paper, we model the performance of the middleware overlay infrastructure using Queueing Network Models. To represent the mobile Thing's connections/disconnections, we model and solve analytically an ON/OFF queueing center. We apply our approach to Streaming interactions with mobile peers. Finally, we validate our model using simulations. The deviations between the performance results foreseen by the analytical model and the ones provided by the simulator are shown to be less than 5%.

International audience

International audience; The mapping process of high performance embedded applications to today's multiprocessor system-on-chip devices suffers from a complex toolchain and programming process. The problem is the expression of parallelism with a pure imperative programming language, which is commonly C. This traditional approach limits the mapping, partitioning and the generation of optimized parallel code, and consequently the achievable performance and power consumption of applications from different domains. The Architecture oriented paraLlelization for high performance embedded Multicore systems using scilAb (ALMA) European project aims to bridge these hurdles through the introduction and exploitation of a Scilab-based toolchain which enables the efficient mapping of applications on multiprocessor platforms from a high level of abstraction. The holistic solution of the ALMA toolchain allows the complexity of both the application and the architecture to be hidden, which leads to better acceptance, reduced development cost, and shorter time-to-market. Driven by the technology restrictions in chip design, the end of exponential growth of clock speeds and an unavoidable increasing request of computing performance, ALMA is a fundamental step forward in the necessary introduction of novel computing paradigms and methodologies.

The mapping process of high performance embedded applications to today's multiprocessor system on chip devices suffers from a complex tool chain and programming process. The problem here is the expression of parallelism with a pure imperative programming language which is commonly C. This traditional approach limits the mapping, partitioning and the generation of optimized parallel code, and consequently the achievable performance and power consumption of applications from different domains. The Architecture oriented paraLlelization for high performance embedded Multicore systems using scilAb (ALMA) European project aims to bridge these hurdles through the introduction and exploitation of a Scilab-based toolchain which enables the efficient mapping of applications on multiprocessor platforms from high level of abstraction. This holistic solution of the toolchain allows the complexity of both the application and the architecture to be hidden, which leads to a better acceptance, reduced development cost, and shorter time-to-market. Driven by the technology restrictions in chip design, the end of exponential growth of clock speeds, and an unavoidable increasing request of computing performance, ALMA is a fundamental step forward in the necessary introduction of novel computing paradigms and methodologies.

The mapping process of high performance embedded applications to today's reconfigurable multiprocessor System-on-Chip devices suffers from a complex toolchain and programming process. Thus, the efficient programming of such architectures in terms of achievable performance and power consumption is limited to experts only. Enabling them to nonexperts requires a simplified programming process that hides the complexity of the underlying hardware - introduced by software parallelism of multiple cores and the flexibility of reconfigurable architectures - to the end user. The Architecture oriented paraLlelization for high performance embedded Multi-core systems using scilAb (ALMA) European project aims to bridge these hurdles through the introduction and exploitation of a Scilab- and architecture-description-language-based toolchain which enables the efficient mapping of applications on multiprocessor platforms from high level of abstraction. This holistic solution of the toolchain allows the complexity of both the application and the architecture to be hidden, which leads to a better acceptance, reduced development costs, and shorter time-to-market.

International audience; Despite the significant investment and growth both in Europe and globally in the development of virtual universities and virtual campuses over the last decade, there have been a number of high-profile projects and initiatives that failed to achieve their intended goals. If such failures are to be avoided in the future, then it is vital that a better understanding of best practice within virtual universities and virtual campuses is achieved. This paper reports on the work of a European Commission Education Audiovisual & Culture Executive Agency (EACEA) co-financed project 'Promoting Best Practice in Virtual Campuses' (PBP-VC), which is aimed at providing a deeper understanding of the key issues and success factors underlying the implementation of virtual campuses. The paper will outline a tentative model of the issues underpinning best practice in virtual campuses which covers areas that include organisational, pedagogical, technological, student/user, financial and consolidation issues derived from an investigation into virtual campus projects and initiatives within Europe. The project is working towards developing a practical framework to help guide the process of creating best practice in virtual campuses, as well as raising awareness of issues and approaches to creating sustainable virtual campuses.

International audience; This roundtable reports on the work of a European Commission DG Education and Culture cofinanced project "PBP-VC Promoting Best Practice in Virtual Campuses" which is aimed at providing a deeper understanding of the key issues and success factors underlying the implementation of virtual campuses. A tentative model of issues underpinning best practice in virtual campuses which covers organisational, pedagogical, technological and student-related issues derived from an investigation into existing EACEA co-financed virtual campus initiatives within Europe will be outlined. The project is working towards developing a practical framework to help guide the process of creating best practice in virtual campuses, as well as raising awareness of issues and approaches to creating sustainable virtual campuses.

International audience; The Virtual Campus for a Sustainable Europe is a network of European universities experienced in e-learning and education for sustainable development who believe in the wealth of opportunities for learners and teachers engaged in e-learning across disciplinary and cultural boundaries. The VCSE shares high quality, inter-disciplinary and trans-disciplinary e-courses on sustainability issues for university students.

International audience; The paper presents the results of the analysis of the difficulties evidenced by the students while approaching some scientific disciplines (the ones the author has been teaching or involved with) and shows various kinds of these problems usually known as preconceptions, misconceptions or mental schemes in students' learning. The work describes then the strategies adopted to help students in overcoming their difficulties by using specific strategies built up with the help of the constructivistic paradigm. It analyzes soon after the experiences made by the author while using Web techniques to support his teaching activity and proposes the model of a special Web site where e-commerce techniques have been adopted. The paper ends with the description of the monitoring process of students' knowledge one can carry out with the above site by using the Data Base it's interfaced with and gives an outline of the possible knowledge paradigms this instrument leads to.

International audience; Interactively explore issues relating to key success factors, best practices within context of e-learning and virtual campuses. Introduce models and a framework aimed at identifying and promoting best practice. Hearing about and learning from your own experiences and work, and getting feedback and comments to issues explored in workshop.

International audience; This roundtable reports on the work of a European Commission DG Education and Culture cofinanced project "PBP-VC Promoting Best Practice in Virtual Campuses" which is aimed at providing a deeper understanding of the key issues and success factors underlying the implementation of virtual campuses. A tentative model of issues underpinning best practice in virtual campuses which covers organisational, pedagogical, technological and student-related issues derived from an investigation into existing EACEA co- financed virtual campus initiatives within Europe will be outlined. The project is working towards developing a practical framework to help guide the process of creating best practice in virtual campuses, as well as raising awareness of issues and approaches to creating sustainable virtual campuses.

International audience; This roundtable reports on the work of a European Commission DG Education and Culture cofinanced project "PBP-VC Promoting Best Practice in Virtual Campuses" which is aimed at providing a deeper understanding of the key issues and success factors underlying the implementation of virtual campuses. A tentative model of issues underpinning best practice in virtual campuses which covers organisational, pedagogical, technological and student-related issues derived from an investigation into existing EACEA co-financed virtual campus initiatives within Europe will be outlined. The project is working towards developing a practical framework to help guide the process of creating best practice in virtual campuses, as well as raising awareness of issues and approaches to creating sustainable virtual campuses.

Introduction Over the past decade, eLearning and the development of virtual campuses have evolved and developed at such a rapid rate that they are commonly accepted as an increasingly popular alternative to traditional face-to-face education (Connolly, MacArthur, Stansfield, & McLellan, 2007; Gunawardena & McIsaac, 2004). The demand for higher education is expanding exponentially throughout the world with the majority of Universities now offering an array of eLearning programs and modules to students from a wide range of different backgrounds and geographical locations. Many universities have entered into partnership agreements with other higher education institutions and education authorities to develop virtual universities and campuses in which students can gain access to a range of educational experiences and resources through virtual means. The development of eLearning and virtual campus opportunities can be widely attributed to the changing nature of employment, where a job for life is no longer the norm, and to the arrival of the 'knowledge-driven society'. In this society, information and knowledge spreading and sharing have a great value due to the complexity of situations and phenomena and for the adaptability and flexibility people are asked for. Many authors hypothesized different scenarios and learning contexts for helping people in the development of the right skills and competences; among them Brown, Collins, and Duguid (1989) and Jonassen (1994) have emphasized the need for open-ended exploratory authentic online learning environments in which learners can develop meaningful and transferable knowledge and understanding. Many eLearning developments and virtual university/campus initiatives were hindered by much of the hype and unrealistic expectations that plagued them in the mid-late 1990s. This contributed to the failure of a number of high profile eLearning and virtual campus initiatives across the world (e.g. California Virtual University, Danish Virtual University). If eLearning and virtual campus initiatives are to be sustainable then it is vital that stakeholders understand how new models of teaching and learning transform the institution and how they can be used to enhance knowledge construction, flexibility, and inclusiveness. There is now an emphasis on constructivism as a philosophical, epistemological, and pedagogical approach. Constructivism focuses on knowledge construction, not knowledge reproduction. Many researchers have expressed their hope that constructivism will lead to better educational software and better learning. This has led to the development of constructivist learning environments (CLEs) that guide and support learners to achieve their intended learning outcomes (Cartelli, 2006; Connolly & Stansfield, 2007). The Development of eLearning and Virtual Campuses within the European Union Over the last five years there have been numerous eLearning and virtual campus initiatives and projects that have been co-financed by the European Commission. Despite the many successes and positive outcomes that have arisen from these projects and initiatives, a European Commission workshop held in 2005 to explore the issues associated with virtual campuses highlighted the need for a critical review of existing projects and initiatives (EACEA, 2005). The workshop highlighted a range of issues that affected the successful implementation and deployment of virtual campuses and their long term sustainability. It was felt that virtual campuses generally have very little contact and interoperability with each other due to: * A general lack of awareness about other virtual campuses; * A lack of self-promotion/dissemination by virtual campuses; * Cross-cultural and linguistic barriers to communication. Much of the relevant data, results, conclusions, and recommendations in relation to best practice gathered from numerous virtual campus projects and initiatives are scattered across numerous publications held within a wide range of individual organizations, and in many cases they are not easily accessible to the wider community. …

International audience; Despite a significant growth in the development of virtual campuses (VCs) across the EU in recent years, the findings from a European Commission DG Education and Culture workshop in 2005 on VCs highlighted a number of concerns relating to VC projects and initiatives across the EU. It was felt that many VCs suffered from a low profile resulting in little support at senior levels, thus hampering their development, as well as having very little contact and interoperability with each other. If eLearning and VC initiatives are to be sustainable within the European Union, then it is vital that stakeholders understand how new models of teaching and learning transform the institution and how they can be used to enhance the flexibility and inclusiveness of the European education system. This paper reports on the work of a European Commission DG Education and Culture co-financed project PBP-VC Promoting Best Practice in Virtual Campuses which is aimed at providing a deeper understanding of the key issues and critical success factors underlying the implementation of VCs. The paper will outline a tentative model of issues underpinning best practice in VCs derived from an initial literature based investigation of existing VC initiatives within Europe. In addition, the project is working towards developing a practical framework to help guide the process of creating best practice in VCs, as well as raising awareness of issues and approaches to creating sustainable VCs.

International audience; Despite a significant growth in the development of virtual campuses (VCs) across the EU in recent years, the findings from a European Commission DG Education and Culture workshop in 2005 on VCs highlighted a number of concerns relating to VC projects and initiatives across the EU. It was felt that many VCs suffered from a low profile resulting in little support at senior levels, thus hampering their development, as well as having very little contact and interoperability with each other. If eLearning and VC initiatives are to be sustainable within the European Union, then it is vital that stakeholders understand how new models of teaching and learning transform the institution and how they can be used to enhance the flexibility and inclusiveness of the European education system. This paper reports on the work of a European Commission DG Education and Culture co-financed project PBP-VC Promoting Best Practice in Virtual Campuses which is aimed at providing a deeper understanding of the key issues and critical success factors underlying the implementation of VCs. The paper will outline a tentative model of issues underpinning best practice in VCs derived from an initial literature based investigation of existing VC initiatives within Europe. In addition, the project is working towards developing a practical framework to help guide the process of creating best practice in VCs, as well as raising awareness of issues and approaches to creating sustainable VCs.

International audience; It is a 2 year EACEA co-financed project (March 2007 -February 2009) It aims at providing a deeper understanding of key issues and critical success factors underlying implementation of Virtual Campuses (VCs)