L’Architrave, le plancher, la plate-forme : nouvelle histoire de la construction

L’horizontalité a toujours donné lieu à des difficultés constructives - lutte contre la pesanteur, résistance à travers le temps - et véhiculé une dimension symbolique source de controverses. C’est à l’histoire des structures horizontales et des savoirs qui en sont issus qu’est consacrée l’étude dirigée par Roberto Gargiani, déjà auteur avec Giovanni Fanelli de l’Histoire de l’architecture moderne : structure et revêtement. Composé d’une centaine d’essais alliant études de cas et approches cr..

L’Architrave, le plancher, la plate-forme : nouvelle histoire de la construction

L’horizontalité a toujours donné lieu à des difficultés constructives - lutte contre la pesanteur, résistance à travers le temps - et véhiculé une dimension symbolique source de controverses. C’est à l’histoire des structures horizontales et des savoirs qui en sont issus qu’est consacrée l’étude dirigée par Roberto Gargiani, déjà auteur avec Giovanni Fanelli de l’Histoire de l’architecture moderne : structure et revêtement. Composé d’une centaine d’essais alliant études de cas et approches cr..

Nikolaus Pevsner : la photographie au service d’une approche typologique de l’histoire de l’architecture

Dans son dernier ouvrage publié en 1976, A History of Building Types (London, Thames and Hudson), l’historien Nikolaus Pevsner étudie les évolutions de l’architecture à travers une méthode typologique : les immeubles sont sélectionnés, classés et analysés en fonction de leur destination et de leur forme spécifique. Les immeubles du XXe siècle sont ainsi analysés à l’aune des œuvres canoniques de la Renaissance et du siècle des Lumières – hôtels de ville, cours de justice, théâtres, musées, prisons, hôpitaux, bibliothèques – des extensions constituées de types qui sont apparus durant le premier âge des machines – gares, halls d’expositions, magasins, usines. À travers ce point de vue, l’intention sous-jacente de l’auteur semble être celle d’une réévaluation du mouvement moderne après son effondrement et en comparaison avec d’autres siècles. Cependant, la fabrication de ce livre encyclopédique demeure problématique : la vision homogène de différentes périodes de l’histoire de l’architecture est, en effet, appuyée par une collection de photographies extrêmement hétérogène. Nous suggérons donc d’évaluer la valeur historiographique de ces représentations et le résultat de la méthode typologique dans l’écriture de l’Histoire.In his last work published in 1976, A History of Building Types (London, Thames & Hudson), the historian Nikolaus Pevsner studies the evolutions of architecture through a typological method: the buildings are selected, classified and analyzed according to their destination and to their specific design. Buildings from the twentieth century are thus analyzed in view of the canonical works of the Renaissance and the age of enlightenment – town halls, law courts, theatres, museums, prisons, hospitals, libraries – of constitute extensions of types which have appeared during the first industrial age – railway stations, exhibition buildings, shops, factories. Through this outlook, the underlying intention of the author seems to be a reevaluation of the Modern Movement after its collapse and in comparison with other centuries. Yet, the making of this encyclopedic book remains problematic: the homogeneous vision of different periods of the history of architecture is indeed supported by an extremely heterogeneous collection of photographs. We thus suggest to evaluate the historiographical value of these representations and the outcomes of the typological method in the writing of history.In seinem letzten, 1976 veröffentlichten Werk A History of Building Types (London, Thames and Hudson) untersucht Nikolaus Pevsner architekturgeschichtliche Entwicklungen mittels der typologischen Methode: Die Bauten werden anhand ihrer jeweiligen Bestimmung und ihrer spezifischen Form ausgewählt, geordnet und untersucht. So werden auch Bauten des 20. Jahrhunderts mit dem Maßstab kanonischer Werke der Renaissance und der Aufklärung analysiert – Rathäuser, Justizpaläste, Theater, Museen, Gefängnisse, Krankenhäuser, Bibliotheken – mit Erweiterung um Bautypen, die in der Zeit der Industrialisierung entstanden sind – Bahnhöfe, Ausstellungshallen, Geschäfte, Fabriken. So scheint es die unterschwellige Intention des Autors zu sein, die Moderne nach ihrem Untergang durch einen Vergleich mit vorangegangenen Jahrhunderten aufzuwerten. Doch bleibt die Erstellung dieses enzyklopädischen Werkes problematisch: Der homogenen Vision von Zeitschichten der Architekturgeschichte steht eine äußerst heterogene Sammlung von Fotografien gegenüber. Anliegen dieses Beitrags ist es daher, den geschichtlichen Wert dieser Darstellungen und die Ergebnisse der typologischen Methode zu hinterfragen und neu zu bewerten

The P2Y1 receptor is involved in the maintenance of glucose homeostasis and in insulin secretion in mice

Pancreatic β cells express several P2 receptors including P2Y1 and the modulation of insulin secretion by extracellular nucleotides has suggested that these receptors may contribute to the regulation of glucose homeostasis. To determine whether the P2Y1 receptor is involved in this process, we performed studies in P2Y1 mice. In baseline conditions, P2Y1-mice exhibited a 15% increase in glycemia and a 40% increase in insulinemia, associated with a 10% increase in body weight, pointing to a role of the P2Y1 receptor in the control of glucose metabolism. Dynamic experiments further showed that P2Y1-mice exhibited a tendency to glucose intolerance. These features were associated with a decrease in the plasma levels of free fatty acid and triglycerides. When fed a lipids and sucrose enriched diet for 15 weeks, the two genotypes no longer displayed any significant differences. To determine whether the P2Y1 receptor was directly involved in the control of insulin secretion, experiments were carried out in isolated Langerhans islets. In the presence of high concentrations of glucose, insulin secretion was significantly greater in islets from P2Y1-mice. Altogether, these results show that the P2Y1 receptor plays a physiological role in the maintenance of glucose homeostasis at least in part by regulating insulin secretion

Conductive-probe atomic force microscopy characterization of silicon nanowire

The electrical conduction properties of lateral and vertical silicon nanowires (SiNWs) were investigated using a conductive-probe atomic force microscopy (AFM). Horizontal SiNWs, which were synthesized by the in-plane solid-liquid-solid technique, are randomly deployed into an undoped hydrogenated amorphous silicon layer. Local current mapping shows that the wires have internal microstructures. The local current-voltage measurements on these horizontal wires reveal a power law behavior indicating several transport regimes based on space-charge limited conduction which can be assisted by traps in the high-bias regime (> 1 V). Vertical phosphorus-doped SiNWs were grown by chemical vapor deposition using a gold catalyst-driving vapor-liquid-solid process on higly n-type silicon substrates. The effect of phosphorus doping on the local contact resistance between the AFM tip and the SiNW was put in evidence, and the SiNWs resistivity was estimated

Écrire l'histoire de l'architecture moderne : enquête sur le genre de la synthèse (1752-1982)

How was the expanded field of historical synthesis of modern architecture as an instituted genre formed? This thesis aims to combine three approaches by examining the circumstances of the development of a range of publications between the eighteenth and twentieth centuries. First, an examination of milieus aims to show how the articulation between a narrative and a panorama of modern architecture led, between 1750 and 1900, to the development of a diversity of types of discourse in the French, German and Anglo-Saxon areas. The study of four moments between 1900 and 1960, from an international perspective, traces the emergence and consolidation of the idea of the "Modern Movement" in architecture. Finally, an examination of the careers and work of four key figures - Charles Jencks, Manfredo Tafuri, Kenneth Frampton and William J.R. Curtis - will enable us to assess the notion of 'critical' history in the context of the emergence of Post-Modernism between 1960 and 1980. This investigation is based on a comparative study of publications in order to examine the conditions of their production in the institutional sphere and in relation to changes in the architectural conjuncture. The aim of this thesis is to show how the historical image of modernity in architecture has been constructed through synthetic discourse, and to evaluate the relationship between history, theory and criticism.Comment s’est formé le champ élargi des synthèses historiques de l’architecture moderne en tant genre institué ? Cette thèse se propose de conjuguer trois approches en examinant les circonstances de l’élaboration d'un ensemble de publications entre le XVIIIe et le XXe siècles. D’abord, une étude de milieux a pour objectif de montrer comment l’articulation entre un récit et un panorama de l’architecture moderne a conduit, entre 1750 et 1900, au développement d’une diversité de types de discours dans les aires française, allemande et anglo-saxonne. Ensuite, l’étude de quatre moments entre 1900 et 1960, dans une perspective internationale, permet de retracer l’émergence et la consolidation de l’idée de « Mouvement moderne » en architecture. Enfin, l’examen des itinéraires et des travaux de quatre acteurs que sont Charles Jencks, Manfredo Tafuri, Kenneth Frampton et William J.R. Curtis permet d’évaluer la notion d’histoire « critique » dans le contexte de l’émergence du Post-modernisme entre 1960 et 1980. Cette enquête s’appuie sur une étude comparée des publications afin d’examiner les conditions de leur production dans la sphère institutionnelle et au regard des évolutions de la conjoncture architecturale. Cette thèse a ainsi pour objectif de montrer comment s’est construite l’image historique de la modernité en architecture par le biais des discours de synthèse, et d’évaluer les rapports entre histoire, théorie et critique

Vers une méthode d’analyse des risques globale de la filière CSC, intégrant plusieurs échelles de temps

Issus de publications récentes, les éléments rapportés ici reflètent la réflexion globale engagée par l’INERIS sur l’analyse des risques de la filière CSC, au sein de plusieurs programmes de recherche - associant divers organismes et experts français - et d’un programme d’appui aux pouvoirs publics

Design of fault trees as a practical method for risk analysis of CCS : application to the different life stages of deep aquifer storage, combining long-term and short-term issues

International audienceINERIS (French National Institute for Industrial Environment and Risks) is involved in assessing accidental and chronic risks in industrial or underground activities. Concerning carbon dioxide storage, INERIS performs integrated risk assessment studies, by integrating both its know-how in industrial safety and the knowledge developed in the context of other underground storages: hydrocarbons, landfill, nuclear waste. Concerning the future development of the CCS technology, a major question is the underground evolution of the CO2 at medium and long time scales. It is necessary to undertake a systemic approach in order to consider all targets at stake and all stages of the CCS chain. INERIS developed a specific method that includes the tools that are used in environmental, health and safety risks. At first, a risk analysis was performed, leading to identify the relevant risk scenarios. There we took into account the possible high content of impurities, and therefore the different exposure routes for man and for the soil/water environment. 8 main 'Impacting phenomena' were defined, they cover the whole CCS chain (capture, transport, injection and long-term storage) and include both accidental and long-term effects. Each Impacting phenomenon gets a series of causes, that were represented in fault trees and were described in a dynamic graph through an adequate software tool. In a second step, the risk scenarios are to be quantified in terms of transfer and effects to the environment, and the estimated flows are to be compared to critical flows. This overall method consists of an integrated risk assessment, and helps in managing the risk for all life stages and all elements of the CCS chain, either at surface level or in the underground

Psychological and physiological effects of bupropion compared to methylphenidate after prolonged administration in healthy volunteers (NCT00285155)

International audiencePURPOSE:Bupropion is largely used as an antidepressant and smoking cessation therapy. The aim of this work was to compare pharmacodynamic properties of bupropion and the amphetamine-like methylphenidate after sustained administration in humans.METHODS:Twelve male volunteers completed this randomized, double-blind, placebo controlled, cross-over study. Bupropion and methylphenidate were administered separately for initial half-dose 6-day periods (150 and 10 mg respectively) followed by full-dose 8-day periods (300 and 20 mg respectively). Outcomes were subjective feelings, cognitive performances, autonomic and physiological parameters.RESULTS:Data are expressed as mean(SEM). After repeated administration, bupropion, like methylphenidate, decreased asthenia-fatigue [44(3.2) and 42(3.7), respectively vs. 53(4.1) for placebo; p = 0.034], despite an impairment of sleep onset [-4.3(3.32) and -1.9(3.76), respectively vs. +7.5(3.69); p = 0.016]. Both drugs increased resting diastolic blood pressure [67.9(1.23) and 65.7(0.98), respectively vs. 62.5(1.42) mm Hg; p = 0.001], body temperature [36.5(0.12) and 36.5(0.14) vs. 36.3(0.10) °C; p = 0.037] and decreased body weight [-0.7(0.23) and -0.6(0.22), respectively vs. +0.2(0.27) kg; p = 0.038]. No significant change could be observed on cognitive functions, appetite and energy consumption.CONCLUSION:Although it may not share all the properties of stimulant drugs, the effect profile of bupropion presents a number of similarities with that of methylphenidate over a 2-week treatment period

Insulin secretion of pancreatic islets from wt and P2Y-deficient mice in the presence of different concentrations of glucose

<p><b>Copyright information:</b></p><p>Taken from "The P2Y receptor is involved in the maintenance of glucose homeostasis and in insulin secretion in mice"</p><p></p><p>Purinergic Signalling 2005;1(2):145-151.</p><p>Published online Jan 2005</p><p>PMCID:PMC2096536.</p><p></p> Results are the mean ± SEM for 26Y35 independent determinations. * < 0.02