Influence de la convection naturelle ou du brassage électromagnétique sur la solidification de lingots d'aluminium

In an experimental model of a parallelepiped ingot, the convective motions of liquid aluminum are either thermally induced or induced by an electromagnetic traveling field. Magnetic field, velocities and temperatures are measured in experiments for steady state and compared to the results of a numerical calculation. In the same experimental system of aluminum-copper ingots were solidified in various conditions, particularly of stirring. Grain structures are observed and analyzed by metallography. A numerical solidification model has been developed which takes into account the interactive effects of the liquid metal motion and heat and mass transfers. The results of this model allow a better understanding of the observed solidification structures.Dans une lingotière expérimentale parallélépipédique, les mouvements convectifs de l’aluminium liquide sont soit d’origine thermique, soit induits par un champ glissant électromagnétique. Champ magnétique, vitesses et températures ont été mesurés dans des expériences en régime permanent et comparés aux résultats d’un calcul numérique. Dans le même dispositif expérimental, des lingots d’alliage d’aluminium-cuivre ont été solidifiés dans des conditions variées, en particulier de brassage. Les structures de grains sont observées et analysées par métallographie. Un modèle numérique de solidification a été développé : il prend en compte les effets interactifs du mouvement du métal liquide et des transferts de chaleur et de masse. Les résultats de ce modèle permettent de mieux comprendre les structures de solidification observées

Assessment of dam trapping efficiency from water residence time: Application to fluvial sediment transport in the Adour, Dordogne, and Garonne River basins (France)

Dam-trapping efficiency can be estimated by using the hydraulic residence time. On the regional scale, the global impact of several dams can be assessed by taking into account the spatial organization of dams along the river network. Therefore, in this study, a method is proposed to estimate the global-trapping efficiency, TEw, for any watershed containing more than one dam. This method is applied to the Adour, Dordogne, and Garonne River watersheds (southwestern France). The spatial organization of dams and its impact on TEw and on sediment yields measured at 37 TSM sampling stations over 2 years are discussed. Positive correlation between drainage areas and river sediment loads corrected from dam regulation using TEw, as well as comparisons between TEw-corrected sediment yields and sediment yields measured upstream from dams, point out the interest of the method in order to reconstitute the natural sediment yields

Rethinking business models for innovation

One of the major challenges confronted by those in charge of technological innovation involves anticipating the value creation model sufficiently early on,in a highly uncertain context both as far as the technology itself is concerned and the potential market. Today, in many industrial sectors, the innovation boundaries have moved towards projects that are more and more exploratory and fuzzy. The simple optimisation of linear processes of the "stage-gate" type is no longer sufficient to build sustainable competitive advantages. The notion of Business Models, when applied to innovation, enables us to describe how a company creates value through innovation, generally within a business ecosystem, and how the value will be distributed between the actors involved. The authors of this book believe that the notions of Business Modelling and value creation are key to all the dimensions of successful innovation, whether technology, marketing, organisational or economically based. Rethinking Business Models for Innovation: this title describes the relationship between thinking, modelling, and also field-testing. The book is based on a series of nine recent cases of innovation involving company managers, often assisted by researchers (the co-authors of each chapter), and how they built and formalised their Business Models and then tested their strategies. After having discovered the variety of the cases, the reader will understand that every innovation situation generates specific questions about Business Models. However, we feel that we can identify three key issues that arise, more or less, in each of these projects. The chapters in this book build on these issues: the identification of sources of value and revenue models (the notion of value creation), the position of the company in the value-network or ecosystem (the sharing of value) and finally the evolution of Business MoDdels over time (the sustainability and the competitiveness of the company). The last chapter goes over all the contributions, exploring the notion of value in the Business Model approach.business model ; innovation ; value ; entrepreneurial project

Loss of independence in Katz's ADL ability in connection with an acute hospitalization: early clinical markers in French older people

Background: The preservation of autonomy and the ability of elderly to carry out the basic activities of daily living, beyond the therapeutic care of any pathologies, appears as one of the main objectives of care during hospitalization. Objectives: To identify early clinical markers associated with the loss of independence in elderly people in short stay hospitals. Methods: Among the 1,306 subjects making up the prospective and multicenter SAFEs cohort study (Sujet Agé Fragile: Évolution et suivi—Frail elderly subjects, evaluation and follow-up), 619 medical inpatients, not disabled at baseline and hospitalized through an emergency department were considered. Data used in a multinomial logistic regression were obtained through a comprehensive geriatric assessment (CGA) conducted in the first week of hospitalization. Dependency levels were assessed at baseline, at inclusion and at 30days using Katz's ADL index. Baseline was defined as the dependence level before occurrence of the event motivating hospitalization. To limit the influence of rehabilitation on the level of dependence, only stays shorter than 30days were considered. Results: About 514 patients were eligible, 15 died and 90 were still hospitalized at end point (n=619). Two-thirds of subjects were women, with a mean age of 83. At day 30 162 patients (31%) were not disabled; 61 (12%) were moderately disabled and 291 severely disabled (57%). No socio-demographic variables seemed to influence the day 30 dependence level. Lack of autonomy (odds ratio (OR)=1.9, 95% confidence interval (CI)=1.2-3.6), walking difficulties (OR=2.7, 95% CI=1.3-5.6), fall risk (OR=2.1, 95% CI=1.3-6.8) and malnutrition risk (OR=2.2, 95% CI=1.5-7.6) were found in multifactorial analysis to be clinical markers for loss of independence. Conclusions: Beyond considerations on the designing of preventive policies targeting the populations at risk that have been identified here, the identification of functional factors (lack of autonomy, walking difficulties, risk of falling) suggests above all that consideration needs to be given to the organization per se of the French geriatric hospital care system, and in particular to the relevance of maintaining sector-type segregation between wards for care of acute care and those involved in rehabilitatio

Scleromyositis: A distinct novel entity within the systemic sclerosis and autoimmune myositis spectrum. Implications for care and pathogenesis

Systemic sclerosis and autoimmune myositis are both associated with decreased quality of life and increased mortality. Their prognosis and management largely depend on the disease subgroups. Indeed, systemic sclerosis is a heterogeneous disease, the two predominant forms of the disease being limited and diffuse scleroderma. Autoimmune myositis is also a heterogeneous group of myopathies that classically encompass necrotizing myopathy, antisynthetase syndrome, dermatomyositis and inclusion body myositis. Recent data revealed that an additional disease subset, denominated “scleromyositis”, should be recognized within both the systemic sclerosis and the autoimmune myositis spectrum. We performed an in-depth review of the literature with the aim of better delineating scleromyositis. Our review highlights that this concept is supported by recent clinical, serological and histopathological findings that have important implications for patient management and understanding of the disease pathophysiology. As compared with other subsets of systemic sclerosis and autoimmune myositis, scleromyositis patients can present with a characteristic pattern of muscle involvement (i.e. distribution of muscle weakness) along with multisystemic involvement, and some of these extra-muscular complications are associated with poor prognosis. Several autoantibodies have been specifically associated with scleromyositis, but they are not currently integrated in diagnostic and classification criteria for systemic sclerosis and autoimmune myositis. Finally, striking vasculopathic lesions at muscle biopsy have been shown to be hallmarks of scleromyositis, providing a strong anatomopathological substratum for the concept of scleromyositis. These findings bring new insights into the pathogenesis of scleromyositis and help to diagnose this condition, in patients with subtle SSc features and/or no autoantibodies (i.e. “seronegative” scleromyositis). No guidelines are available for the management of these patients, but recent data are showing the way towards a new therapeutic approach dedicated to these patients

Late Quaternary co-seismic sedimentation in the Sea of Marmara's deep basins

25 pages, 15 figures, 1 tableauInternational audienceThe deep, northern, part of the Sea of Marmara (northwestern Turkey) is composed of several aligned, actively subsiding, basins, which are the direct structural and morphological expression of the North Anatolian Fault's northern branch. The last 20 kyr of their sedimentary fill (lacustrine before 12 kyr BP) have been investigated through giant piston coring onboard R/V MARION-DUFRESNE (MARMACORE Cruise, 2001) and chirp subbottom profiler onboard R/V ATALANTE during MARMARASCARPS Cruise (2002). Especially during the lacustrine stage, the infilling of the deep basins (Tekirda?, Central, Kumburgaz, and Çinarcic Basins; up to 1250 m depth) was dominated by turbidites (with coarse mixed siliciclastic and bioclastic basal part), intercalated in “hemipelagic-type” finegrained calcareous and slightly siliceous clays. Often – especially in the thickest ones – the turbidites show strong segregation and a sharp boundary between coarse part and suspendedload part. In the Central Basin, 8 m of a unique sedimentary event include a 5 to 8m-thick “homogenite” well imaged on seismic profiles. The latter is interpreted as related to a major – possibly triggered - tsunami effect, as described in the Eastern Mediterranean by Kastens and Cita (1981). In the marine (Holocene) upper part of the sedimentary fill, repeated to-and-from structures, affecting silt or fine sand, are evidencing seiche-like effects and, thus, earthquake triggering. Detailed correlations between two deep coring sites (1250 and 1200 m) indicate more than 100 % overthickening in the deepest one; this implies specific processes of distribution of terrigenous input by dense hyperpycnal currents (high kinetic energy, seiche effect, complex reflections on steep slopes). The peculiar sedimentary infilling of the Sea of Marmara's Central Basin (and, by extrapolation, of the whole set) is tentatively interpreted as a direct consequence of the strong seismic activity; the imprint of the latter is more obvious prior to the base of the Holocene, as environmental conditions favoured marginal accumulation (especially on the southern shelf) of large amounts of erosion products available for mass wasting

: Lessons from entrepreneurial projects

International audienceOne of the major challenges confronted by those in charge of technological innovation involves anticipating the value creation model sufficiently early on,in a highly uncertain context both as far as the technology itself is concerned and the potential market. Today, in many industrial sectors, the innovation boundaries have moved towards projects that are more and more exploratory and fuzzy. The simple optimisation of linear processes of the "stage-gate" type is no longer sufficient to build sustainable competitive advantages. The notion of Business Models, when applied to innovation, enables us to describe how a company creates value through innovation, generally within a business ecosystem, and how the value will be distributed between the actors involved. The authors of this book believe that the notions of Business Modelling and value creation are key to all the dimensions of successful innovation, whether technology, marketing, organisational or economically based. Rethinking Business Models for Innovation: this title describes the relationship between thinking, modelling, and also field-testing. The book is based on a series of nine recent cases of innovation involving company managers, often assisted by researchers (the co-authors of each chapter), and how they built and formalised their Business Models and then tested their strategies. After having discovered the variety of the cases, the reader will understand that every innovation situation generates specific questions about Business Models. However, we feel that we can identify three key issues that arise, more or less, in each of these projects. The chapters in this book build on these issues: the identification of sources of value and revenue models (the notion of value creation), the position of the company in the value-network or ecosystem (the sharing of value) and finally the evolution of Business MoDdels over time (the sustainability and the competitiveness of the company). The last chapter goes over all the contributions, exploring the notion of value in the Business Model approach.L'innovation technologique, qu'elle soit conduite par des start-ups ou par de grandes entreprises, n'est plus une condition suffisante de la création de valeur. Créer de la valeur sur des marchés nouveaux nécessite le plus souvent de repenser l'organisation de l'entreprise, sa façon de faire des affaires, ses partenariats stratégiques, autrement dit, son business model. Cet ouvrage se veut un guide pour les porteurs de projets d'innovation en leur fournissant des outils de compréhension et d'analyse de la dimension stratégique de leur projet. Les études de cas présentées sont le fruit d'une collaboration étroite entre les porteurs de chacun des projets et des chercheurs en management de l'innovation reconnus. Au travers de ces cas, trois grandes problématiques sont abordées : l'identification des sources de valeur chez les clients potentiels, la position que l'entreprise pourra prendre dans son écosystème et enfin l'évolution des business models dans le temps. Sur chacun des cas, le lecteur aura accès à une compréhension fine des problèmes stratégiques posés par l'innovation ainsi que des outils de management mis en œuvre pour aider à réfléchir et à agir. (http://www.rethinkingbusinessmodel.net/

Radio sur fibre pour un réseau local domestique millimétrique

National audienceLe projet FUI ORIGIN (Optical-Radio Infrastructure for Gigabit/s Indoor Networks) adresse le marché du Réseau Local Domestique pour lequel il propose une nouvelle infrastructure à très haut débit associant un câblage à fibre optique avec une diffusion radio 60GHz. Les premiers tests de cette infrastructure ont donné des résultats probants : un lien Radio sur Fibre en fréquence intermédiaire étendant la portée d'une transmission radio millimétrique est ici proposé et caractérisé complètement en termes d'EVM. Ce concept est validé par l'utilisation de produits commerciaux Wireless HD. Les études se poursuivent pour intégrer les systèmes optique-microondes en utilisant des composants bas coûts et innovants, comme les phototransistors SiGe/Si et des VCSEL analogiques