Robert Vion (Ed.) Les sujets et leurs discours. Énonciation et interaction

Convenons avec Véronique, citant Baggioni, que « la production du sens (est) positivement ou en creux, l'une des thématiques majeures des sciences humaines et sociales depuis leur émergence à la fin du XVIIIe siècle », partant, qu'on ne peut se passer de penser le sujet, voire de le nommer, quelque éviction/exhibition qu'il ait connues dans l'histoire de ses théorisations. Convenons aussi que ses désignations, fonction des rôles qu'on lui assigne – dans un continuum sujet autonome/acteur soc..

Guy Fève, Polynésie, polynésiens, hier et aujourd'hui

Guy Fève propose un ensemble d’études interdisciplinaires sur les représentations et leur localisation, au sein de l’archipel polynésien et de ses imaginaires. Pour R. Gobern, la variété tahitienne du français (FT) atteste un phénomène d’appropriation et de réinvestissement local du français, par un double processus de transfert de la syntaxe polynésienne et de créativité lexicale sur la langue française. Le résultat se différencie d’un créole ou d’un registre du français, le FT possédant ses..

Guy Fève, Polynésie, polynésiens, hier et aujourd'hui

Guy Fève propose un ensemble d’études interdisciplinaires sur les représentations et leur localisation, au sein de l’archipel polynésien et de ses imaginaires. Pour R. Gobern, la variété tahitienne du français (FT) atteste un phénomène d’appropriation et de réinvestissement local du français, par un double processus de transfert de la syntaxe polynésienne et de créativité lexicale sur la langue française. Le résultat se différencie d’un créole ou d’un registre du français, le FT possédant ses..

NMR and LDA evidence for spiral magnetic order in the chain cuprate LiCu2O2

We report on {6,7}Li nuclear magnetic resonance measurements of the spin-chain compound LiCu2O2 in the paramagnetic and magnetically ordered states. Below T about 24 K the NMR lineshape presents a clear signature of incommensurate (IC) static modulation of the local magnetic field consistent with an IC spiral modulation of the magnetic moments. {7}Li NMR reveals strong phason-like dynamical fluctuations extending well below 24 K. We hypothesize that a series of phase transitions at 24.2, 22.5, and 9 K reflects a "Devil's staircase" type behavior generic for IC systems. LDA based calculations of exchange integrals reveal a large in-chain frustration leading to a magnetical spiral.Comment: 4 pages, 4 figure

Reconstruction 3D du bâti par la technique des ombres chinoises

National audienceDans cet article, nous effectuons la reconstruction 3D du bâti à partir d'images satellitaires. Nous nous écartons de l'approche classique qui consiste à considérer le problème comme un problème inverse qui doit être résolu en utilisant deux images stéréoscopiques et en les mettant en correspondance. Au contraire, nous montrons qu'il est plus simple de résoudre le problème directement par essais/erreurs comme on on le fait très naturellement pour produire des ombres chinoises. Nous montrons notamment que cette approche ne nécessite pas un temps de calcul considérable, grâce à la puissance de calcul d'OpenGL qui s'appuie sur une carte graphique. Les premiers résultats obtenus montrent la pertinence de l'approche adoptée. En particulier, elle permet de résoudre des ambiguïtés pour lesquelles l'inversion du problème serait quasiment impossible

Bone marrow fibrosis – the basis of mielofibrosis: pathogenesis, prognostication and antifibrogenic targeted strategies.

Bone marrow fibrosis is a key patological feature and major diagnostic criterion of mielofibrosis. Although bone marrow fibrosis is manifested in a variety of malignant  and non-malignant disease states, the deposition of reticulin and collagen fibrosis in the bone marrow of patients with myelofibrosis is believed to be mediated by the mielofibrosis of hematopoietic stem/progenitor cells, contributing to an impaired microenvironment toward malignant over normal hematopoiesis. The increased expression of pro­inflammatory cytokines, transforming growth factor-β, impaired megakaryocyte function and aberrant JAK-STAT signaling are the peculiarities of pathogenesis of bone marrow fibrosis. Hematopoietic stem cell transplantation remains the only therapeutic approach that reliably results in resolution of  bone marrow fibrosis in patients with mielofibrosis. In the work we review the pathogenesis, biological consequences and prognostic results of impact of bone marrow fibrosis. We discuss the rationale of various anti-fibrogenic treatment strategies targeting at clonal hematopoietic stem/progenitor cells, aberrant signaling pathway, fibrogenic cytokines, and tumor microenvironment

Effect of Laser Optoperforation of the Zona Pellucida on Mouse Embryo Development in vitro

Laser operations on cells and embryos are an important field of current photobiology and biophotonics. The high power density of tightly focused laser irradiation provides an efficient impact on matter of cells or embryos. Precise focusing of the laser spot allows strictly controlled perforation of the membrane. The present work was devoted to studying the influence of optoperforation of mammalian embryonic zona pellucida with a tightly focused laser beam with 1.48-µm wavelength on further development of the embryo. Such a laser operation was proposed for application in in vitro fertilization (IVF) practice and intracytoplasmic sperm injection into the oocyte (ICSI). For cultured in vitro oocytes and embryos, the process of natural exiting from the zona pellucida ("hatching") is often impaired, which decreases probability of implantation and pregnancy The goals of the present work were to determine the influence of different manipulations on development of embryos in vitro until blastocyst formation and on the ISSN 0006-2979, Biochemistry (Moscow), 2015, Vol. 80, No. 6, pp. 769-775. © Pleiades Publishing, Ltd., 2015. Original Russian Text © E. O. Zakharchenko, A. D. Zalessky, A. A. Osychenko, A. S. Krivokharchenko, A. K. Shakhbazyan, A. V. Ryabova, V. A. Nadtochenko, 2015, published in Biokhimiya, 2015 769 * To whom correspondence should be addressed. Abstract-The effect of laser optical perforation of the zona pellucida on the viability and development of mouse embryos has been studied. Operations of zona pellucida thinning and single or double perforation were carried out on 2-cell embryo, morula, and blastocyst stages with a laser pulse (wavelength 1.48 µm, pulse duration 2 ms). Embryo development up to the blastocyst stage and hatching efficiency were statistically analyzed. It was found that 2-cell or morula stage embryo zona pellucida thinning or single perforation did not affect development to the blastocyst stage and number of hatched embryos, but it accelerated embryo hatching compared to control groups one day earlier in vitro. Double optoperforation on 2-cell embryo or morula stage did not significantly affect development to the blastocyst stage, but it strongly decreased the number of hatched embryos. Also, zona pellucida perforation at the blastocyst stage had a negative effect: hatching did not occur after this manipulation. Blastocyst cell number calculation after single zona pellucida perforation at 2-cell and morula stages showed that cell number of hatching or hatched blastocysts did not differ from the same control groups. This fact points out that the laser single optoperforation method is a useful and safe experimental tool that allows further manipulations within the zona pellucida. Effect of Laser Optoperforation of the Zon

Magnetic structures and reorientation transitions in noncentrosymmetric uniaxial antiferromagnets

A phenomenological theory of magnetic states in noncentrosymmetric tetragonal antiferromagnets is developed, which has to include homogeneous and inhomogeneous terms (Lifshitz-invariants) derived from Dzyaloshinskii-Moriya couplings. Magnetic properties of this class of antiferromagnets with low crystal symmetry are discussed in relation to its first known members, the recently detected compounds Ba2CuGe2O7 and K2V3O8. Crystallographic symmetry and magnetic ordering in these systems allow the simultaneous occurrence of chiral inhomogeneous magnetic structures and weak ferromagnetism. New types of incommensurate magnetic structures are possible, namely, chiral helices with rotation of staggered magnetization and oscillations of the total magnetization. Field-induced reorientation transitions into modulated states have been studied and corresponding phase diagrams are constructed. Structures of magnetic defects (domain-walls and vortices) are discussed. In particular, vortices, i.e. localized non-singular line defects, are stabilized by the inhomogeneous Dzyaloshinskii-Moriya interactions in uniaxial noncentrosymmetric antiferromagnets.Comment: 18 pages RevTeX4, 13 figure

АМПЛИТУДНАЯ МОДУЛЯЦИЯ СВЕТА ПУТЕМ ЭЛЕКТРООПТИЧЕСКОГО УПРАВЛЕНИЯ МНОГОЛУЧЕВОЙ ИНТЕРФЕРЕНЦИЕЙ В ИНТЕРФЕРОМЕТРЕ ФАБРИ–ПЕРО

In present work the questions related to decreasing the control voltage of amplitude Fabry–Perot modulators with conserving their high efficiency have been considered. Schematic models of high-efficient amplitude Fabry–Perot electrooptical modulators have been proposed.В настоящей работе были рассмотрены вопросы, связанные с уменьшением управляющего напряжения амплитудных модуляторов Фабри–Перо с сохранением их высокой эффективности. Были предложены схематические модели высокоэффективных амплитудных электрооптических модуляторов Фабри–Перо

Femtosecond Nanosurgery: Laser Enucleation of Chromatin in the Oocyte

A method for cell enucleation by femtosecond laser nanosurgery has been developed. This enucleation technique allows DNA destruction with high precision and low invasiveness, showing good efficiency. The technology of such operations is of great importance in medical and scientific practice.Работа выполнена при поддержке гранта РНФ № 21-75-10155