A New Hemodynamic Ex Vivo Model for Medical Devices Assessment

Introduction: In stent restenosis (ISR) remains a major public health concern with an increased morbidity, mortality and health-related costs. Drug-eluting stents (DES) have reduced ISR, but are associated with healing-related issues or hypersensitivity reactions, leading to an increased risk of late acute stent thrombosis. Evaluations of new DES are based on animal models or in vitro release systems which show several limitations. The role of flow and shear stress on endothelial cell and ISR has also been emphasized. The aim of this work was to design and first evaluate an original bioreactor, reproducing ex vivo hemodynamic and biological conditions similar to human conditions, to further evaluate new DES. Methods & Results: This bioreactor was designed to study up to 6 stented arteries connected in bypass, immersed in a culture box, in which circulated a physiological systolo-diastolic resistive flow. Two centrifugal pumps drove the flow. The principal pump generated pulsating flows by modulation of rotation velocity, and the second pump worked at constant rotation velocity, ensuring the counter pressure levels and backflows. The flow rate, the velocity profile, the arterial pressure and the resistance of the flow were adjustable. The bioreactor was placed in an incubator to reproduce a biological environment. A first experience of feasibility was realized over a period of 24 days. Three rat aortic thoracic arteries were placed into the bioreactor, immersed in cell culture medium change every 3 days, and with a circulating systole diastolic flux circulating among the entire experimentation. There was no infection, no leak. At the end of experimentation, a morphometric analysis was performed confirming the viability of the arteries. Conclusion: We design and patent an original hemodynamic ex vivo model to further study new DES and ISR. We will next validate this ex vivo model of ISR reproducing this experimentation with stented arteries. Once validated, this bioreactor will allow characterization of the velocity field and drug transfers within a stented artery with new functionalized DES, with experimental means not available in vivo. Another main point will be the reduction of animal experimentation, and the availability of first results of new DES in human tissues (human infra popliteal or coronary arteries collected during human donation)

A Picture of the Research Field of Doctoral Education from the Students’ Perspectives : Studies Using Questionnaires and Scales

Peer reviewe

Development of a multibody model of a sprayer

peer reviewedA multibody model of a sprayer boom including the suspension was developed by using ADAMS 11.0 (Mechanical Dynamics). The model was designed with the aim to describe the dynamic behaviour of different types of booms and suspensions (double trapezium, trapezium, pendulum, …). This was obtained by creating a general model in which geometrical (dimensions) and mechanical parameters (mass and inertia, friction coefficients, stiffness and damping coefficients of the hinges, …) of the system were easily modified. A graphical interface especially designed authorised this easy modification. The validation of the model was obtained by measuring in real conditions the frame movements as solicitations and the boom movements as responses. The method was applied on a trailed sprayer equipped with a boom of 24 m and a trapezoidal suspension. Good accordance was found between measured and simulated vertical displacements. The model may decrease the development costs of suspension and boom designs

Un intrapreneur ordinaire au coeur d'une implantation réussie d'un changement organisationnel

National audienceThis article contributes to entrepreneurial change literature through the study of the relationship between forms of corporate entrepreneurship and types of entrepreneur. We focused on managerial innovations occurring in an unfavorable organizational context (former public administration), highlighting the innovative practices of a department manager that facilitated the implementation of change. Our research question is the following : in a generally unfavorable internal context, how can a middle manager work towards a successful change through a form of ordinary Intrapreneurship (Alter, 2000) ? To address that question, we analyzed the ordinary and creative practices, devised and implemented by this intrapreneur, and have put them in perspective with his individual characteristics. One of the main contributions of this research is to show a link between an ordinary form of innovation and the necessary entrepreneurial skills, leading us to rethink the possible links between types of innovation and managers' personalities.Cet article propose d'apporter une contribution au changement entrepreneurial à travers l'étude du lien entre forme d'intrapreneuriat et type d'entrepreneur. Pour cela, nous nous intéressons à une forme d'intrapreneuriat s'inscrivant dans un contexte organisationnel peu favorable à l'innovation (ancienne administration), en mettant en avant les pratiques innovantes d'un responsable de service ayant favorisé l'implantation d'un changement organisationnel. Notre question de recherche est : dans un contexte interne globalement défavorable, comment un gestionnaire intermédiaire peut œuvrer à la réussite d'un changement à travers une forme d'intrapreneuriat ordinaire (Alter, 2000) ? Pour y répondre, nous avons analysé les pratiques ordinaires et créatives, décidées et implantées par cet intrapreneur, et les avons mises en perspective avec ses caractéristiques individuelles. Une des principales contributions de cette recherche est de montrer un lien entre une forme d'innovation ordinaire et les compétences requises de la part de l'intrapreneur, nous amenant à repenser les liens possibles entre type d'innovation et personnalité des managers

La Banque Laford : un terreau pour l'intrapreneuriat ? - Cas pédagogique CCMP n° G 1763

Disponible sur le site de la Centrale de Cas et de Médias Pédagogiques : http://www.ccmp.fr/collection-ccmp/cas-la-banque-laford-un-terreau-pour-lintrapreneuriatEtude de cas CCMPLa Banque LAFORD est confrontée depuis plus de 10 ans à des changements majeurs dans son environnement ainsi que dans ses processus internes qui font suite au passage d'une banque axée sur les particuliers à une banque généraliste s'adressant également aux organisations (associations, grandes et petites entreprises, etc.). Cette banque est caractérisée par de multiples activités regroupées au sein de filiales régionales, les " directions régionales financières " (DRF). Chaque DRF supervise les agences bancaires de sa zone géographique. Depuis un petit nombre d'années l'accent a été mis sur un important développement de nouveaux services dédiés aux organisations en raison d'un fort potentiel de produit net bancaire et de rentabilité avec un risque maîtrisé. Ces services bancaires ont été conçus par le siège et déployés au niveau des différentes DRF au sein des entités en relation avec les organisations. Ceci implique, entre autres choses, l'implantation d'un changement organisationnel centralisé au sein des services backoffice de La Banque LAFORD. Le cas est centré sur l'action d'un des six managers d'unité concerné par ce changement, Antoine Lemarchand, qui, au contraire des autres unités, a réussi avec succès à mettre en œuvre ce changement dans une démarche intrapreunariale

Middle manager as the interface between global strategy and strategy practice: Enacting strategy through materializing

How practice is/gets aligned with strategy is a topic of great interest for the SP literature. This paper is about the middle manager's role in enacting strategy through his practices and production of textual tools that provide a frame and sensegiving resulting in a local adjustment of the global strategy, contributing to a successful implementation. The important role of the middle manager as the interface between global strategy and strategy practice, particularly through his production of textual tools that creates alignment, is highlighted in an empirical study of a new strategy implementation in an organization. More specifically, this paper focus on the critical role a middle manager played in determining how a global strategy was enacted (strategy practice) and how the textual tools (materializing) managers produce shaped this strategy enactment by embodying his sensegiving and conveying it successfully to frontline staff. We used Latour works (1999; 1997) to inquire the materialization of strategy in textual tools (i.e.: how tools through materializing processes frame the multiple activities) and studied three different categories that we identified: operating texts, geography design and time/timing texts. Our findings are important in suggesting that enacted strategy is not only supported by traditional strategic tool, nor by oral activity, but mainly and structurally by the materiality that is produced by middle managers to give sense to the strategy to employees. Second we add value to empirical work on strategizing because of the diversity of our data: our sample included top managers, managers and employees, and various texts were documented. They gave us the capacity to analyze the important role of the middle manager as the interface between global strategy and strategy practice