Nouveaux regards sur l'histoire de la France dans la Seconde Guerre mondiale

À propos de l’histoire de la France pendant la Seconde Guerre mondiale, le moment nous a paru opportun de présenter un dossier qui puisse combiner un bilan historiographique incluant des recherches nouvelles ainsi qu’un aperçu des pistes neuves à explorer. Nous disposons déjà de travaux récents qui effectuent un bilan sur des aspects de la question. Ainsi, l’historiographie de Vichy en France a fait l’objet d’un colloque organisé en juin 2005 par l’université de Tel Aviv et par l’Institut d’études politiques de Paris, sous la direction de Jean-Pierre Azéma et d'Elie Barnavi. Un autre colloque s’est tenu à Lyon en 2008 sur l’historiographie de la Résistance, faisant suite en cela à l’ouvrage de Laurent Douzou (La Résistance française, une histoire périlleuse, Paris, Le Seuil, 2005). L’objet de ce dossier consiste à poursuivre la perspective historiographique ainsi amorcée en la combinant avec l’apport de publications récentes émanant de chercheurs confirmés et d’énoncer à leur suite des pistes de recherche pour l’avenir.Sans prétendre à une exhaustivité illusoire, nous avons privilégié parmi les recherches contemporaines celles qui délibérément désenclavent la période de l’Occupation et de la guerre. Désenclavement dans le temps d’abord, en tentant d’échapper au cadre strict des années 1940-1944, voire 1939-1945. Cela en s’attachant à des travaux qui parviennent à montrer que certaines mesures adoptées sous la contrainte ou à la faveur de celle-ci, avaient été envisagées avant la guerre et ont été en partie conservées après la Libération. Ou bien, pour ce qui intéresse la rupture constituée par la Résistance ou par les politiques de persécution, en cherchant la place de l’avenir dans ces engagements ainsi que le rôle de la mémoire dans l’analyse ultérieure de ces politiques.Désenclavement dans l’espace également. L’intention d’élargir l’objet s’adresse ainsi à la dimension géopolitique. On a évité la focalisation exclusive sur le régime de Vichy et ses débats franco-français pour inclure également le poids de l’occupant, curieusement absent de nombreux travaux portant sur la période limitée à celle de l’Occupation. Mais le désenclavement s’applique aussi à l’espace social. On ne s’est pas restreint au seul point de vue des élites masculines et des décideurs publics ou privés.Enfin, quant aux objets d’étude eux-mêmes, nous avons étendu la recherche à d’autres champs que les domaines politique et culturel. D’où notre intérêt pour les travaux qui font place aux données économiques et sociales lato sensu, qui prennent en considération l’évolution du droit sur la décennie, ou qui examinent les pratiques judiciaires lorsqu’elles mêlent le temps long (notamment les considérations de genre) et le temps court de l’épuration.Une réévaluation de la période de l’Occupation et de la guerre se dessine à travers ces aperçus. Chaque article intègre les grandes dynamiques à l’œuvre et les met en relations : les politiques allemandes avec celles du gouvernement de Vichy ; l’Etat avec la société, à travers la séquence parfois erratique reliant les discours aux pratiques ; le court terme conjoncturel et le long terme issu de la IIIe République. Il ne s’agit pas d’effacer les ruptures et en particulier d’occulter le caractère exorbitant du droit commun de certaines politiques. Au contraire, il s’agit de repérer l’exacte ligne de la rupture lorsqu’elle se produit sous les dehors d’une continuité apparente. Et, à l’inverse, lorsqu’il y a rupture assumée comme dans le cas de la Résistance ou de la politique antisémite, d’en repérer l’insertion dans les temps longs du passé, de l’avenir escompté ou de la mémoire transmise.Claire Andrieu, Michel Margaira

The science program of the TCV tokamak: exploring fusion reactor and power plant concepts

TCV is acquiring a new 1 MW neutral beam and 2 MW additional third-harmonic electron cyclotron resonance heating (ECRH) to expand its operational range. Its existing shaping and ECRH launching versatility was amply exploited in an eclectic 2013 campaign. A new sub-ms real-time equilibrium reconstruction code was used in ECRH control of NTMs and in a prototype shape controller. The detection of visible light from the plasma boundary was also successfully used in a position-control algorithm. A new bang-bang controller improved stability against vertical displacements. The RAPTOR real-time transport simulator was employed to control the current density profile using electron cyclotron current drive. Shot-by-shot internal inductance optimization was demonstrated by iterative learning control of the current reference trace. Systematic studies of suprathermal electrons and ions in the presence of ECRH were performed. The L–H threshold power was measured to be ~50–75% higher in both H and He than D, to increase with the length of the outer separatrix, and to be independent of the current ramp rate. Core turbulence was found to decrease from positive to negative edge triangularity deep into the core. The geodesic acoustic mode was studied with multiple diagnostics, and its axisymmetry was confirmed by a full toroidal mapping of its magnetic component. A new theory predicting a toroidal rotation component at the plasma edge, driven by inhomogeneous transport and geodesic curvature, was tested successfully. A new high-confinement mode (IN-mode) was found with an edge barrier in density but not in temperature. The edge gradients were found to govern the scaling of confinement with current, power, density and triangularity. The dynamical interplay of confinement and magnetohydrodynamic modes leading to the density limit in TCV was documented. The heat flux profile decay lengths and heat load profile on the wall were documented in limited plasmas. In the snowflake (SF) divertor configuration the heat flux profiles were documented on all four strike points. SF simulations with the EMC3-EIRENE code, including the physics of the secondary separatrix, underestimate the flux to the secondary strike points, possibly resulting from steady-state E × B drifts. With neon injection, radiation in a SF was 15% higher than in a conventional divertor. The novel triple-null and X-divertor configurations were also achieved in TCV

Le capitalisme et l'État

Kuisel Richard F., Bouvier Jean, Bloch-Lainé François, Fourastié Jean, Cazes Bernard, Wolff Jacques, Lévy-Leboyer Maurice, Lombarès Michel de, Fridenson Patrick, Rousso Henry, Andrieu Claire, Margairaz Michel, Bédarida François. Le capitalisme et l'État. In: Bulletin de l'Institut d'Histoire du Temps Présent, n°18, décembre 1984. pp. 16-40

Silicon micromachined ultrasonic scalpel for the dissection and coagulation of tissue

This work presents a planar, longitudinal mode ultrasonic scalpel microfabricated from monocrystalline silicon wafers. Silicon was selected as the material for the ultrasonic horn due to its high speed of sound and thermal conductivity as well as its low density compared to commonly used titanium based alloys. Combined with a relatively high Young's modulus, a lighter, more efficient design for the ultrasonic scalpel can be implemented which, due to silicon batch manufacturing, can be fabricated at a lower cost. Transverse displacement of the piezoelectric actuators is coupled into the planar silicon structure and amplified by its horn-like geometry. Using finite element modeling and experimental displacement and velocity data as well as cutting tests, key design parameters have been identified that directly influence the power efficiency and robustness of the device as well as its ease of controllability when driven in resonance. Designs in which the full- and half-wave transverse modes of the transducer are matched or not matched to the natural frequencies of the piezoelectric actuators have been evaluated. The performance of the Si micromachined scalpels has been found to be comparable to existing commercial titanium based ultrasonic scalpels used in surgical operations for efficient dissection of tissue as well as coaptation and coagulation of tissue for hemostasis. Tip displacements (peak-to-peak) of the scalpels in the range of 10-50μm with velocities ranging from 4 to 11m/s have been achieved. The frequency of operation is in the range of 50-100kHz depending on the transverse operating mode and the length of the scalpel. The cutting ability of the micromachined scalpels has been successfully demonstrated on chicken tissue

Silicon micromachined ultrasonic scalpel for the dissection and coagulation of tissue

This work presents a planar, longitudinal mode ultrasonic scalpel microfabricated from monocrystalline silicon wafers. Silicon was selected as the material for the ultrasonic horn due to its high speed of sound and thermal conductivity as well as its low density compared to commonly used titanium based alloys. Combined with a relatively high Young’s modulus, a lighter, more efficient design for the ultrasonic scalpel can be implemented which, due to silicon batch manufacturing, can be fabricated at a lower cost. Transverse displacement of the piezoelectric actuators is coupled into the planar silicon structure and amplified by its horn-like geometry. Using finite element modeling and experimental displacement and velocity data as well as cutting tests, key design parameters have been identified that directly influence the power efficiency and robustness of the device as well as its ease of controllability when driven in resonance. Designs in which the full- and half-wave transverse modes of the transducer are matched or not matched to the natural frequencies of the piezoelectric actuators have been evaluated. The performance of the Si micromachined scalpels has been found to be comparable to existing commercial titanium based ultrasonic scalpels used in surgical operations for efficient dissection of tissue as well as coaptation and coagulation of tissue for hemostasis. Tip displacements (peak-to-peak) of the scalpels in the range of 10–50 μm with velocities ranging from 4 to 11 m/s have been achieved. The frequency of operation is in the range of 50–100 kHz depending on the transverse operating mode and the length of the scalpel. The cutting ability of the micromachined scalpels has been successfully demonstrated on chicken tissue