74 research outputs found
Les perspectives de la recherche : patrimoine et architecture, urbanisme et paysages
Animé par Karen Bowie, ce débat doit permettre à chacun des participants de réagir aux propositions de nouvelles recherches faites par le comité scientifique de l’AHICF dans le domaine du patrimoine ferroviaire, de l’architecture, de l’urbanisme et des paysages. Il réunit François Loyer, directeur de recherche au CNRS, Evelyne Lohr, conservateur chargée de l’Inventaire au Service du patrimoine culturel du Département de Seine-Saint-Denis, Anne Hecker, géographe, maître de conférences à l’université de Nancy II, Jean-François Belhoste, directeur d’études à l’École pratique des hautes études, et Catherine Bergeal, sous-directrice de la Nature et des Paysages au ministère de l’Écologie. En introduction, F. Loyer remarque que le chemin de fer, loin de devenir obsolète comme on pouvait le penser dans les années 1960, est devenu le vecteur de la mobilité moderne. La notion de patrimoine se définit alors comme un passage de relais entre deux époques et non comme la nostalgie d’une culture matérielle disparue. Si patrimoine et architecture ont longtemps été antinomiques, comme urbanisme et paysage, on constate aujourd’hui des rapprochements qui renouvellent ces notions. Le débat devra donc inclure les paysages en rapport avec les chemins de fer, les abords du bâti, l’architecture des bâtiments et le design, « architecture sans site ». Chacun des participants expose les perspectives de son domaine de recherche. Evelyne Lohr analyse le rôle des emprises ferroviaires dans le territoire du département de la Seine-Saint-Denis concerné par de très importantes mutations. Elle montre comment, et avec quelles méthodes d’analyse rationnelle et documentée, le Service du patrimoine culturel contribue à la compréhension de ce territoire complexe et lui apporte une cohérence, en comprenant le patrimoine comme un moteur d’évolution et non un objet de nostalgie. Les directions de recherche sont multiples : impact des réseaux sur le territoire, chemin de fer comme facteur d’urbanisation, réutilisation de son patrimoine, paysages créés par le chemin de fer… Les problèmes posés par l’inventaire le sont autant, comme la méthode d’étude à appliquer à un patrimoine linéaire sur une portion de territoire, ou la reconnaissance d’un patrimoine technique parfois difficile à comprendre. Anne Hecker aborde, en termes de patrimoine, l’infrastructure ferroviaire, la voie ferrée et son emprise. Patrimoine linéaire étendu et aux caractères bien marqués (profil, tracé, modes de construction innovants, support de mémoire ouvrière et locale, conservatoire pour une faune et une flore remarquables), il reste méconnu. Pourtant, la question de sa conservation partielle, comme témoin et explication de l’évolution du paysage, doit être posée, dans la double perspective de sa valorisation par la réouverture de voies au trafic ou par la transformation de voies déferrées en équipements touristiques, vélos-routes et voies vertes. Cette dernière n’assure que rarement la préservation de l’image du passé ferroviaire et sa médiation au public. Les différentes solutions d’aménagement qui seront proposées doivent dans tous les cas s’appuyer sur la connaissance de ce patrimoine. J.-F. Belhoste revient pour sa part sur son expérience de vingt années au sein de l’Inventaire général et en particulier sur le rôle de la protection au titre des monuments historiques et de la politique du ministère de la Culture dans l’orientation des recherches et sur l’apport que ces préoccupations patrimoniales ont pu représenter pour la recherche dans le domaine des chemins de fer. Les recherches patrimoniales prenant pour point de départ la culture matérielle sont venues abonder la recherche historique plus large avec par exemple des avancées sur l’histoire des techniques de construction ou sur la notion de réseau, qui inclut désormais les installations qui permettent l’exploitation (comme les ateliers). Cependant, le rapport entre l’histoire des techniques et le patrimoine reste une question difficile, comme le montre le privilège donné aux architectes par rapport aux ingénieurs dans la définition de la valeur patrimoniale d’une œuvre. Enfin, l’évolution des institutions chargées de l’étude et de la protection du patrimoine, comme celle des acteurs du secteur ferroviaire, demande l’établissement de nouveaux rapports qui favorisent la recherche. En conclusion, C. Bergeal souligne combien, pour être vraiment durable et optimal par rapport au territoire, un aménagement nécessite sa connaissance approfondie. La question qui se pose est donc la façon dont nous pouvons aujourd’hui faire reconnaître un patrimoine partagé dans l’aménagement durable de nos territoires.Round table with Jean-François BELHOSTE, Catherine BERGEAL, Karen BOWIE, Anne HECKER, Evelyne LOHR and François LOYER Led by Karen Bowie, this discussion allowed each participant to respond to new research proposals from the AHICF academic committee in the areas of railway heritage, architecture, urbanism, and landscape. Grouped around the table were François Loyer, research director at the CNRS, Evelyne Lohr, inventory curator at the Service du patrimoine culturel for the department of Seine-Saint-Denis, Anne Hecker, a geographer and lecturer at the university of Nancy II, Jean-François Belhoste, senior researcher and study director at the Ecole pratique des hautes études, and Catherine Bergeal, director of Nature and Landscape at the Ministry of Ecology. By way of introduction, F. Loyer remarked that far from becoming obsolete as one might have thought in the 1960s, the railway has become the vector of modern mobility. Consequently, the notion of heritage defines itself not simply as nostalgia for a bygone material culture but as a passageway that links two different periods. If cultural heritage and architecture have long been opposed to each other, like urbanism and landscape, similarities are now being noticed that reconstruct these polar notions. As a result, the discu ssion must also include topics such as landscapes in relation to the railway, areas in the vicinity of construction, and design or “architecture without a site.” Each of the participants presented perspectives from their area of research. Evelyne Lohr analyzed the role of the railway’s territorial rights-of-way in the department of Seine-Saint-Denis, which has been affected by very important transformations. She demonstrated how and with which methods of rational and documentary analysis the Service du patrimoine culturel has contributed to an understanding of this complex territory and unified it, interpreting cultural heritage as a force for change and not as an object of nostalgia. Such research can take many directions: for instance, the impact of networks on territory, the railway as a factor of urbanization, the re-use of cultural heritage, and landscapes created by the railway. Such a list presents its own critical problematics, such as which method of study should be applied to heritage of railway lines over a specific parcel of territory, or how to acknowledge a technical heritage that is sometimes difficult to comprehend. Anne Hecker approaches railway infrastructure, the railway itself, and its hold in terms of cultural heritage. The patrimony of railway lines, epitomized by strongly inflected characteristics (profile, route, innovative methods of construction, a buttress for occupational and local recollections, a conservatory for remarkable flora and fauna) remains unknown. The issue of its partial preservation, however, as a marker and explanation of the evolution of the landscape, must be examined from the double perspective of its valorization through the reopening of routes to traffic or by the transformation of discontinued lines into tourist facilities, bike routes, and nature trails. The latter only rarely assure the preservation of the image of the railway’s past and its public mediation. The various planning solutions that will be proposed must be consistently based on knowledge of this cultural heritage. J.-F. Belhoste returned to his twenty years of experience working closely with the State Inventory Service, particularly addressing the role of protecting historical monuments and the Ministry of Culture’s policies regarding research directions and the contribution that patrimonial concerns represent for research in the field of railway studies. Taking material culture as its starting point, research on heritage has broadened the scope of historical research with advances in the history of construction techniques or the notion of the network, which from now on must include the installations that enable operations (like workshops). The relationship between the history of techniques and heritage, however, remains a delicate question, as demonstrated by the privilege granted to architects rather than engineers in defining the patrimonial value of a work. Finally, the evolution of the institutions responsible for studying and preserving this heritage, as well as changes that affect those who are involved with the railway sector, demands that new connections be created that favor and support research. In conclusion, C. Bergeal stressed how important intimate knowledge of a territory is for the longevity and optimal suitability of developmental planning The issue then becomes how we can acknowledge today a heritage that is shared by the long-term developmental planning of our regional landscape
Splendeur du béton : les prédécesseurs et l'oeuvre d'Auguste Perret
Referències bibliogràfiques. Índe
Exploring the synthetic potency of the first furanothioglycoligase through original remote activation.
International audienceThioglycosidic bonds are of utmost importance in biomolecules as their incorporation led to more stable glycomimetics with potential drug activities. Until now only chemical methods were available for their incorporation into glycofuranosyl conjugates. Herein, we wish to describe the use of the first furanothioglycoligase for the preparation of a great variety of thioaryl derivatives with moderate to excellent yields. Of great interest, a stable 1-thioimidoyl arabinofuranose, classically used in chemical glycosylation, was able to efficiently act as a donor through an original enzymatic remote activation mechanism. Study of the chemical structure as well as the nucleophilicity of the thiol allowed us to optimize this biocatalyzed process. As a consequence, this mutated enzyme constitutes an original, mild and eco-friendly method of thioligation
Regulation of hepatic cardiolipin metabolism by TNFα: Implication in cancer cachexia
International audienceCardiolipin (CL) content accumulation leads to an increase in energy wasting in liver mitochondria in a rat model of cancer cachexia in which tumor necrosis factor alpha (TNFα) is highly expressed. In this study we investigated the mechanisms involved in liver mitochondria CL accumulation in cancer cachexia and examined if TNFα was involved in this process leading to mitochondrial bioenergetics alterations. We studied gene, protein expression and activity of the main enzymes involved in CL metabolism in liver mitochondria from a rat model of cancer cachexia and in HepaRG hepatocyte-like cells exposed to 20 ng/ml of TNFα for 12 h. Phosphatidylglycerolphosphate synthase (PGPS) gene expression was increased 2.3-fold (p < 0.02) and cardiolipin synthase (CLS) activity decreased 44% (p < 0.03) in cachectic rat livers compared to controls. CL remodeling enzymes monolysocardiolipin acyltransferase (MLCL AT-1) activity and tafazzin (TAZ) gene expression were increased 30% (p < 0.01) and 50% (p < 0.02), respectively, in cachectic rat livers compared to controls. Incubation of hepatocytes with TNFα increased CL content 15% (p < 0.05), mitochondrial oxygen consumption 33% (p < 0.05), PGPS gene expression 44% (p < 0.05) and MLCL AT-1 activity 20% (p < 0.05) compared to controls. These above findings strongly suggest that in cancer cachexia, TNFα induces a higher energy wasting in liver mitochondria by increasing CL content via upregulation of PGPS expression
CD40-Activated B Cells Can Efficiently Prime Antigen-Specific Naïve CD8+ T Cells to Generate Effector but Not Memory T cells
Background: The identification of the signals that should be provided by antigen-presenting cells (APCs) to induce a CD8 + T cell response in vivo is essential to improve vaccination strategies using antigen-loaded APCs. Although dendritic cells have been extensively studied, the ability of other APC types, such as B cells, to induce a CD8 + T cell response have not been thoroughly evaluated. Methodology/Principal Findings: In this manuscript, we have characterized the ability of CD40-activated B cells, stimulated or not with Toll-like receptor (TLR) agonists (CpG or lipopolysaccharide) to induce the response of mouse naïve CD8 + T cells in vivo. Our results show that CD40-activated B cells can directly present antigen to naïve CD8 + T cells to induce the generation of potent effectors able to secrete cytokines, kill target cells and control a Listeria monocytogenes infection. However, CD40-activated B cell immunization did not lead to the proper formation of CD8 + memory T cells and further maturation of CD40-activated B cells with TLR agonists did not promote the development of CD8 + memory T cells. Our results also suggest that inefficient generation of CD8 + memory T cells with CD40-activated B cell immunization is a consequence of reduced Bcl-6 expression by effectors and enhanced contraction of the CD8 + T cell response. Conclusions: Understanding why CD40-activated B cell immunization is defective for the generation of memory T cells and gaining new insights about signals that should be provided by APCs are key steps before translating the use of CD40-B cel
Minimal information for studies of extracellular vesicles 2018 (MISEV2018):a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines
The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points
Le monde moderne
Depuis la constitution de l’État grec, les gouvernements successifs se sont heurtés à un manque chronique de moyens – difficulté presque insurmontable, déjà relevée par Ludwig von Maurer lorsqu’il siégeait au Conseil de régence durant la minorité du roi Othon. Cela ne les a pas empêchés de travailler à la mise en place d’une administration cohérente, capable de s’opposer aux pressions de groupes d’intérêts portés par diverses minorités en rivalité pour l’exercice du pouvoir – d’où la longue e..
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