Fermi-liquid instabilities at magnetic quantum phase transitions

This review discusses instabilities of the Fermi-liquid state of conduction electrons in metals with particular emphasis on magnetic quantum critical points. Both the existing theoretical concepts and experimental data on selected materials are presented; with the aim of assessing the validity of presently available theory. After briefly recalling the fundamentals of Fermi-liquid theory, the local Fermi-liquid state in quantum impurity models and their lattice versions is described. Next, the scaling concepts applicable to quantum phase transitions are presented. The Hertz-Millis-Moriya theory of quantum phase transitions is described in detail. The breakdown of the latter is analyzed in several examples. In the final part experimental data on heavy-fermion materials and transition-metal alloys are reviewed and confronted with existing theory.Comment: 62 pages, 29 figs, review article for Rev. Mod. Phys; (v2) discussion extended, refs added; (v3) shortened; final version as publishe

Evaluation de la sévérité du choc hémorragique post-traumatique par la mesure de l oxygénation tissulaire dans le muscle thénar (résultats préliminaires)

Lors de la prise en charge de patients polytraumatisés, il existe de nombreux marqueurs d évaluation de la sévérité du choc. Dans cette étude nous tentons d évaluer la sévérité du choc hémorragique post traumatique par la mesure de l oxygénation tissulaire dans le muscle thénar à l aide d un monitorage non invasif. La sévérité du choc est évaluée au troisième à l aide du score SOFA. Ce travail est le première partie d une étude multicentrique prospective qui étudiera 100 patients à l issue de la période de recueil.After a poly trauma, during the first moments, it exists some values which evaluate severity of shock and the prognosis of patients. In this study, we try to evalue severity of hemorrhagic shock using measure of tissular oxygen saturation in thenar muscle with non invasive monitoring. The shock severity is determinated with the SOFA score.This represent the first part of a multicentric and prospective study.GRENOBLE1-BU Médecine pharm. (385162101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Temperature-dependent Fermi surface in CeBiPt

Shubnikov-de Haas (SdH) and Hall-effect measurements of CeBiPt and LaBiPt reveal the presence of very small Fermi surfaces with hole-like charge carriers for both semimetals. Reasonable agreement with band structure calculations is achieved when taking spin-orbit coupling into account and assuming localized Cc 4f electrons. For CeBiPt, we observe a strong temperature dependence of the SdH frequency, i.e., an increase from similar to 35 T at 10 K to similar to 60 T at 0.4K, indicating a possible hybridization of the f electrons

Magnetic order and transport in the heavy-fermion system CeCu

We report on extensive elastic neutron scattering to determine the wave vector of the magnetic order in CeCu$_{6-x}$Aux single crystals for x > 0.1. For all values of x investigated (0.2, 0.3, 0.5, 1.0) we find long-range incommensurate antiferromagnetic order with an ordering vector ${\bf Q}\approx$ (0.625 0 0.275) for x=0.2, nearly unchanged for x=0.3, and ${\bf Q}\approx$ (0.59 0 0) for x=0.5, staying roughly the same for x=1.0. In addition, short-range correlations are observed for x=0.2, reminiscent of those found previously for x=0.1. The ordered magnetic moment is found to increase rapidly for small x, and more slowly for the larger x values. The increase of the specific-heat anomaly at the ordering temperature with x is in qualitative accord with this behavior. Finally, data of the electrical resistivity for current flow along the three crystallographic directions are presented, showing a clear signature of the magnetic order. A theoretical interpretation of the interplay of magnetic order and transport in terms of (i) the partial suppression of the Kondo effect by the staggered magnetization and (ii) the anisotropic band structure induced by the staggered field is shown to account well for the data, provided the ordering vector ${\bf Q}$ is close to $2 k_{F}$, where kF is a typical Fermi momentum

Metastatic and non-metastatic sentinel inguinofemoral lymph nodes in vulvar cancer show an increased lymphangiogenesis

Introduction and objective. Lymph node involvement is a strong predictor of disease recurrence and patient survival in vulvar cancer. The aim of the study was to evaluate the feasibility of sentinel lymph node (SLN) screening, the incidence of skip metastases, and lymph node lymphangiogenesis. Materials and method. Fifty-five patients participated in this prospective, single centre study. A double SLN screening method was employed using radiocolloid (technetium-99 sulfur colloid) and 1.0% Isosulfan Blue. Immunohistochemistry, using a mouse monoclonal antibody against D2–40, was used to evaluate lymphatic vessel density (LVD). All calculations were performed using STATISTICA software v. 10 (StatSoft, USA, 2011); p<0.05 was considered significant. Results. Using both methods of SLN detection, 100% accuracy was achieved, and skip metastases were diagnosed in only one woman (1.82%). Peri-tumour median LVD was significantly increased compared with matched intra-tumour samples (p<0.001), while median LVD was significantly lower in negative, compared with positive SLN, regardless of whether matched non-SLN were negative (p<0.001) or positive (p=0.005). Metastatic SLN exhibited significantly higher median LVD compared with matched negative non-SLN (p=0.015), while no significant difference in median LVD was detected between positive SLN and matched positive non-SLN. However, negative SLN had a significantly higher median LVD compared with matched negative non-SLN (p = 0.012). Conclusions. SLN detection is a safe and feasible procedure in vulvar cancer. In patients without nodular involvement, SLN, compared with non-SLN, exhibited significantly higher median LVD, which may be an indication of its preparation to host metastases, and thus requires further investigation