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A denoising method is reported for the treatment of neutron scattering data obtained with position-sensitive detectors, which enhances the information obtained from weak and very weak Bragg peaks. The core element of the method is the application of a Laplacian of Gaussian filter calculated using the parameters of the resolution of the instrument. This adaptation of well established image-processing techniques offers a very efficient way to denoise the data, as shown through the application of the reported method to a study of the magnetic Bragg peaks of a 300 nm-thick epitaxial Cr film. The procedure enhances the contrast by a factor of more than 35 and thus allows precise determination of the position of the integration mask. The large contrast enhancement also lowers the detection threshold of standard elastic neutron diffractometers down to the level usually available solely on optimized triple-axis spectrometers.

Half metal magnets are of great interest in the field of spintronics because of their potential full spin polarization at the Fermi level (E F) and low magnetization damping. The high Curie temperature and the predicted 0. 7 eV minority spin gap make the Co 2 MnSi Heusler compound very promising for applications. We investigated the half-metallic magnetic character of this compound using spin-resolved photoemission , ab initio calculation , and ferromagnetic resonance. At the surface of Co 2 MnSi , a gap in the minority spin channel is observed , leading to 100% spin polarization. However , this gap is 0. 3 eV below E F , and a minority spin state is observed at E F. We show that a minority spin gap at E F can nevertheless be recovered either by changing the chemical composition of the compound or by covering the surface by Mn , MnSi , or MgO. This spin-gap recovery results in extremely small damping coefficients , reaching values as low as 7 × 10 −4 .

Nuclear erythroid 2–related factor 2 (Nrf2) is an oxidative stress–mediated transcription factor with a variety of downstream targets aimed at cytoprotection. Nrf2 has recently been implicated as a new therapeutic target for the treatment of liver disease. Here, we focus on the most common liver diseases—nonalcoholic fatty liver disease/steatohepatitis, alcoholic liver disease, and drug-induced liver injury—and highlight areas in the development of these conditions where activation of Nrf2 may alleviate disease progression.

WOS:000368442100010; International audience; We report on the magnetization at the Cr/MgO interface, which we studied through two complementary techniques: angle-resolved photoemission spectroscopy and polarized neutron reflectivity. We experimentally observe an enhanced interface magnetization at the interface, yet with values much smaller than the ones reported so far by theoretical and experimental studies on Cr(001) surfaces. Our findings cast some doubts on the interpretations on previous works and could be useful in antiferromagnetic spin torque studies.

During the early 80s, advanced techniques for the deposition of ultra-thin metal films were developed. This led to the fabrication of new artificial materials consisting of different materials stacked in thin sandwiches (hetero-structures). The combination of these different types of materials gave rise to new physical phenomena. The first new phenomenon to be probed was the magnetic exchange coupling in super-lattices. It appeared that magnetic layers separated by non magnetic spacer layers can be magnetically coupled. The coupling can be ferromagnetic, anti-ferromagnetic or more complex (quadratic or even helical). The coupling can also change sign (from ferro to anti-ferro) as a function of the spacer layer thickness. Such phenomena were observed in rare-earth super-lattices (Gd/Y, Dy/Y, Gd/Dy, Ho/Y), transition metals super-lattices (Fe/Cr, Co/Cu, Fe/V, Co/Ru), and mixing of semiconductors and metals (Fe/Si, Fe/Ge). The field is still expanding as new systems are being synthesized, especially with mag...

Introduction La sarcoidose est une granulomatose d’etiologie indeterminee. Les manifestations dermatologiques s’observent dans environ 25 % des cas. Les options therapeutiques pour la sarcoidose cutanee sont limitees et le traitement des formes etendues et/ou affichantes est mal codifie. Voici notre experience relative aux anti-TNFα pour 5 patients atteints de sarcoidose cutanee en echec de traitement. Observations Cinq patients (3 hommes et 2 femmes), avec un âge moyen de 53 ans [38–66], presentant une sarcoidose cutanee affichante et refractaire a plusieurs traitements (methotrexate, antipaludeens de synthese [APS], tacrolimus topique et corticotherapie generale), etaient traites par infliximab (n = 4) ou adalimumab (n = 1). Les formes cliniques correspondaient aux lesions suivantes : lupus pernio (n = 1), papules seules (n = 1), papules et nodules (n = 1), papules et plaques (n = 2). Quatre patients avaient une atteinte du visage et un patient presentait des lesions sur un tatouage etendu du dos. L’indication des anti-TNFα etait exclusivement cutanee chez 4 patients et cutaneo-articulaire chez 1 patient. La reponse aux anti-TNFα etait evaluee au cours du traitement par le meme clinicien en reference aux photographies initiales. Une evolution rapidement favorable etait notee chez tous les patients. Ils demeuraient en remission clinique complete et prolongee sous traitement avec un suivi median de 60 mois [4–84]. Seule persistait une hyperpigmentation post-inflammatoire residuelle chez les 2 patients de phototype VI. Aucun effet indesirable n’etait survenu. Discussion L’impact psychosocial des lesions dermatologiques de sarcoidose peut affecter negativement la qualite de vie des patients, justifiant alors d’un traitement. Sont habituellement proposes les dermocorticoides, le thalidomide, les APS et les immunosuppresseurs (IS). Notre serie suggere une efficacite rapide et prolongee des anti-TNFα, sans complication notable. Plusieurs publications de cas isoles ou petites series rapportent l’efficacite des anti-TNFα pour le traitement des sarcoidoses refractaires. Cependant, il est constate des complications infectieuses et des rechutes frequentes a l’arret du traitement. Dans notre serie, la bonne tolerance est liee a l’absence de corticotherapie ou IS concomitant, puisqu’il s’agit d’atteinte principalement cutanee. Compte tenu des resultats de nos observations et des donnees physiopathologiques connues sur la sarcoidose, nous suggerons de poursuivre ce traitement a long terme, comme cela est deja le cas dans le psoriasis, pour prevenir le risque de recidive. Conclusion Les anti-TNFα semblent etre un traitement efficace, durable et bien tolere de la sarcoidose cutanee, permettant de le proposer en seconde ligne en cas d’echec des DMARDs. Ces resultats meriteraient d’etre confirmes par une etude controlee, sur une cohorte de plus grande taille.

Birds are uricotelic and, like humans, maintain high plasma urate concentrations (∼300 μM). The majority of their urate waste, as in humans, is eliminated by renal proximal tubular secretion; however, the mechanism of urate transport across the brush-border membrane of the intact proximal tubule epithelium during secretion is uncertain. The dominance of secretory urate transport in the bird provides a convenient model for examining this process. The present study shows that short hairpin RNA interference (shRNAi) effectively knocked down gene expression of multidrug resistance protein 4 (Mrp4; 25% of control) in primary monolayer cultures of isolated chicken proximal tubule epithelial cells (cPTCs). Control and Mrp4-shRNAi-treated cPTCs were mounted in Ussing chambers and unidirectional transepithelial fluxes of urate were measured. To detect nonspecific effects, transepithelial electrical resistance (TER) and sodium-dependent glucose transport (Iglu) were monitored throughout experiments. Knocking down Mrp4 expression resulted in a reduction of transepithelial urate secretion to 35% of control with no effects on TER or Iglu. Although electrical gradient-driven urate transport in isolated brush-border membrane vesicles was confirmed, potassium-induced depolarization of the plasma membrane in intact cPTCs failed to inhibit active transepithelial urate secretion. However, electrical gradient-dependent vesicular urate transport was inhibited by the MRP4 inhibitor MK-571 also known to inhibit active transepithelial urate transport by cPTCs. Based on these data, direct measure of active transepithelial urate secretion in functional avian proximal tubule epithelium indicates that Mrp4 is the dominant apical membrane exit pathway from cell to lumen.

Changes in expression of liver ABC transporters have been described during acute APAP intoxication. However, the effect of APAP on brain ABC transporters is poorly understood. The aim of this study was to evaluate the effect of APAP on brain ABC transporters expression and the role of the oxidative stress sensor Nrf2. Male C57BL/6J mice were administered APAP (400 mg/kg) for analysis of brain mRNA and protein expression of Mrp1-6, Bcrp and P-gp. The results show induction of P-gp, Mrp2 and Mrp4 proteins, with no changes in Bcrp, Mrp1 or Mrp5-6. The protein values were accompanied by corresponding changes in mRNA levels. Additionally, brain Nrf2 nuclear translocation and expression of two Nrf2 target genes, NAD(P)H:quinone oxidoreductase 1 (Nqo1) and Hemoxygenase 1 (Ho-1), was evaluated at 6, 12 and 24 h after APAP treatment. Nrf2 nuclear content increased by 58% at 12 h after APAP along with significant increments in mRNA and protein expression of Nqo1 and Ho-1. Furthermore, APAP treated Nrf2 knockout mice did not increase mRNA or protein expression of Mrp2 and Mrp4 as observed in wildtypes. In contrast, P-gp induction by APAP was observed in both genotypes. In conclusion, acute APAP intoxication induces protein expression of brain P-gp, Mrp2 and Mrp4. This study also suggests that brain changes in Mrp2 and Mrp4 expression may be due to in situ Nrf2 activation by APAP, while P-gp induction is independent of Nrf2 function. The functional consequences of these changes in brain ABC transporters by APAP deserve further attention. Fil: Ghanem, Carolina Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Farmacológicas (i); Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina Fil: Rudraiah, Swetha. University Of Connecticut; Estados Unidos Fil: Bataille, Amy M.. University Of Connecticut; Estados Unidos Fil: Vigo, María B.. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Farmacológicas (i); Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina Fil: Goedken, Michael J.. Rutgers University. Office of Translational Science; Estados Unidos Fil: Manautou, José E.. University Of Connecticut; Estados Unidos

The orthorhombic compound ${\mathrm{NdFe}}_{2}{\mathrm{Al}}_{10}$ has been studied by powder and single-crystal neutron diffraction. Below ${T}_{N}=3.9$ K, the ${\mathrm{Nd}}^{3+}$ magnetic moments order in a double-$\mathbit{k}$ [${\mathbit{k}}_{1}=(0,\frac{3}{4},0)$, ${\mathbit{k}}_{2}=(0,\frac{1}{4},0)$] collinear magnetic structure, whose unit cell consists of four orthorhombic units in the $b$ direction. The refinements show that this structure consists of (0 1 0) ferromagnetic planes stacked along $b$, in which the moments are oriented parallel to $a$ (the easy anisotropy axis according to bulk magnetization measurements) and nearly equal in magnitude ($\ensuremath{\approx}1.7--1.9\phantom{\rule{0.222222em}{0ex}}{\ensuremath{\mu}}_{\text{B}}$). The alternating eight-plane sequence providing the best agreement to the data turns out to be that which yields the lowest exchange energy if one assumes antiferromagnetic near-neighbor exchange interactions with ${J}_{1}\ensuremath{\gg}{J}_{2},{J}_{3}$. With increasing temperature, the single-crystal measurements indicate the suppression of the ${\mathbit{k}}_{2}$ component at $T=2.7$ K, supporting the idea that the anomalies previously observed around 2--2.5 K result from a squaring transition. In a magnetic field applied along the $a$ axis, the magnetic Bragg satellites disappear at ${H}_{c}=2.45$ T, in agreement with earlier measurements. Comparisons are made with related magnetic orders occurring in $\mathrm{Ce}{T}_{2}{\mathrm{Al}}_{10}$ ($T=$ Ru, Os) and ${\mathrm{TbFe}}_{2}{\mathrm{Al}}_{10}$.

International audience; The study, tailoring, and control of the coupling between magnetic layers triggered the development of spintronics and has been up to now focused on systems comprising at least one ferromagnetic layer. Here we present a system where two antiferromagnetic layers separated by an ultrathin tunnel barrier interact with each other. We have studied with neutron and x-ray diffraction two sets of Cr/MgO/Cr trilayers, with either thin (five monolayers or less) or thick (eight monolayers or more) MgO layers, along with isolated Cr layers used as references. While the behavior of the trilayers with thick MgO layers can be explained by the strain state of each layer, that of trilayers with thin barriers cannot be related to the well known behavior of isolated chromium layers. We indeed report in these samples the presence of anomalous magnetic phases (modified propagation vector, direction of spins and propagation vectors inconsistent with the strain state of the sample) that we ascribe to the existence of a tunnel magnetic coupling between the AF layers through the insulating barrier. This unexpected finding opens opportunities for spintronics using solely antiferromagnets.

The Piconcentration of mammalian cerebrospinal fluid (CSF) is about one-half that of plasma, a phenomenon also shown here in the spiny dogfish, Squalus acanthias. The objective of the present study was to characterize the possible role of the choroid plexus (CP) in determining CSF Piconcentration. The large sheet-like fourth CP of the shark was mounted in Ussing chambers where unidirectional33Pifluxes revealed potent active transport from CSF to the blood side under short-circuited conditions. The flux ratio was 8:1 with an average transepithelial resistance of 87 ± 17.9 Ω·cm2and electrical potential difference of +0.9 ± 0.17 mV (CSF side positive). Active Piabsorption from CSF was inhibited by 10 mM arsenate, 0.2 mM ouabain, Na+-free medium, and increasing the K+concentration from 5 to 100 mM. Li+stimulated transport twofold compared with Na+-free medium. Phosphonoformic acid (1 mM) had no effect on active Pitransport. RT-PCR revealed both Pitransporter (PiT)1 and PiT2 (SLC20 family) gene expression, but no Na+-Picotransporter II (SLC34 family) expression, in the shark CP. PiT2 immunoreactivity was shown by immunoblot analysis and localized by immunohistochemistry in (or near) the CP apical microvillar membranes of both the shark and rat. PiT1 appeared to be localized primarily to vascular endothelial cells. Taken together, these data indicate that the CP actively removes Pifrom CSF. This process has transport properties consistent with a PiT2, Na+-dependent transporter that is located in the apical region of the CP epithelium.

Equipe 101 : Nanomagnétisme et électronique de spin; International audience; We have undertaken a detailed study of the Cr surface and Cr/MgO interface electronic properties by symmetryand angle- resolved photoemission spectroscopy on a Cr(001) surface covered or not with 1.2 monolayer MgO. For the bare Cr(001) film, the experimental bulk dispersions are in good agreement with the theoretical band structure, and characteristic antiferromagnetic features like the antiferromagnetic gap at the X point are observed. However, by covering the Cr film by 1.2 monolayer MgO, the observed experimental dispersions are strongly perturbed as a result of the existence of metal- induced gap states in the MgO film. By carrying out normal emission measurements, we detect two 2D localized states for the Cr(001) surface that persist at the Cr/MgO interface: a Delta 1 state at very low binding energy, which is usually associated with Cr surface magnetism, and an additional resonant Delta 5 state, which shall play a crucial role for transport and coupling in Cr/MgO epitaxial systems.

We report on two independent measurements of the spin polarization at the Fe 3 O 4 / γ - Al 2 O 3 interface. Fe 3 O 4 / γ - Al 2 O 3 (1 1 1) bilayers have been epitaxially grown by oxygen-assisted molecular beam epitaxy onto α - Al 2 O 3 (0 0 0 1) substrates and some were covered ex situ by a cobalt electrode. Spin resolved photoemission yield to a negative spin polarization ( ≃ - 40 %) while transport measurements on Fe 3 O 4 / γ - Al 2 O 3 / Co magnetic tunnel junctions show a positive TMR, which suggest that the tunnel spin polarization at the Fe 3 O 4 / γ - Al 2 O 3 interface is positive.

Introduction Les manifestations cutanees du syndrome uretro-oculo-articulaire (syndrome de Fiessinger-Leroy-Reiter) sont rares mais souvent evocatrices et specifiques. Nous rapportons le 3 e cas de la litterature ayant repondu sous infliximab. Observations Nous rapportons le cas d’un homme de 28 ans, travaillant dans la production agro-alimentaire, ayant presente un syndrome uretero-oculo-articulaire (uretrite, conjonctivite, spondylarthrites axiales et peripheriques) associe a des lesions dermatologiques. Ces dernieres etaient pustuleuses et psoriasiformes : elles siegeaient en plaques sur le dos, prenaient la forme d’une keratodermie blennorragique de Vidal et Jacquet avec l’aspect typique de clous de tapissier sur les plantes des pieds, evoquaient une acrodermatite continue d’Hallopeau aux orteils. Une atteinte muqueuse etait egalement presente avec une balanite circinee et des erosions buccales. La chronicite du tableau avait entraine une alteration de l’etat general avec un malade asthenique et amaigrit de 20 kg, ainsi qu’une impotence majeure a la marche. Le malade etait HLA B27 positif, les prelevements uretraux et la coproculture etaient negatifs, la serologie VIH egalement, la ponction articulaire sterile. Les polyarthrites resistaient aux lignes successives par AINS, sulfasalazine, corticotherapie systemique. Un traitement par doxycycline pendant 7 jours puis infliximab etait alors introduit, avec une nette efficacite sur les composantes articulaires et cutanees. Discussion Ce malade a presente la forme complete du syndrome uretro-oculo-articulaire. L’atteinte dermatologique de ce syndrome est presente dans 20 % des cas, la manifestation la plus frequente etant la balanite circinee (20 %) tandis que l’aspect classique en clous de tapissier n’est present que dans 8 % des cas. Ce syndrome s’integre dans le cadre des arthrites reactionnelles. Le micro-organisme causal n’est pas retrouve dans environ 50 % des cas. Les cas associes a un typage HLA B27 ainsi qu’a Chlamydia ont un risque plus important d’evolution chronique defavorable. Un traitement antibiotique a montre son interet uniquement en cas d’uretrite causale a C. trachomatis . L’efficacite des anti-TNF alpha dans les arthrites reactionnelles n’a fait l’objet d’aucune etude de grande envergure. Cependant, lors d’une evolution chronique avec echappement aux therapeutiques habituelles (AINS, corticotherapie systemique, sulfasalazine, methotrexate), une trentaine de succes ont ete rapportes. Concernant l’atteinte dermatologique de ce syndrome, on ne recense que 2 cas traites avec succes par infliximab et 1 cas par etanercept. Voici un 4 e cas suggerant l’interet des anti-TNF alpha. Conclusion Les anti-TNF alpha semblent etre efficaces dans les arthrites reactionnelles dont le syndrome uretro-oculo-articulaire tant sur l’atteinte articulaire que cutanee, comme l’illustre notre observation. Ils sont a reserver en derniere ligne apres echec des therapeutiques habituelles.

Introduction La dermatite atopique (DA) severe de l’adulte, lorsqu’elle resiste aux traitements topiques, est traitee par immunosuppresseurs systemiques comme la ciclosporine, le methotrexate, l’azathioprine ou le mycophenolate mofetil. Cependant, ces traitements systemiques sont parfois mal toleres. Nous avons traite 7 malades par photochimiotherapie extracorporelle (PCE). La PCE consiste a prelever par apherese les cellules mononuclees autologues, a les irradier par lumiere UVA en presence d’une molecule photo-activable, le 8-methoxypsoralene, puis a les reinjecter au malade. Patients et methodes Il s’agit d’une etude retrospective de 7 malades traites par PCE. Les patients inclus, etaient adultes, presentaient une DA severe (SCORAD superieurs a 40), resistante aux traitements topiques, et avec echec d’au moins un traitement systemique. Les seances de PCE etaient realisees au rythme de 1 cycle de 2 seances sur 2 jours consecutifs toutes les 2 semaines pendant 4 mois puis 1 cycle par mois dans le service de nephrologie du CHRU de Lille. Resultats Cas 1 : la PCE permettait une nette amelioration, la patiente a beneficie de 22 cycles de PCE pour une duree totale de 17 mois. La PCE etait stoppee a cause d’un probleme d’abord veineux. Cas 2 : la PCE est efficace, la patiente est traitee par PCE depuis 18 mois (SCORAD a 52 avant traitement puis a 26 au 13 e cycle). Cas 3 : la PCE ayant une efficacite tres moderee (SCORAD a 42 avant traitement puis a 44 au 12 e cycle), un traitement par methotrexate a ete associe et a permis une tres nette amelioration. Le patient est encore en cours de traitement (15 cycles de PCE sur une duree de 11 mois). Cas 4–7 : la PCE etait peu efficace, les seances etaient interrompues apres respectivement 4, 6, 8 et 10 cycles. Discussion Dans la litterature, l’efficacite de la PCE dans la DA severe de l’adulte a ete rapportee dans plusieurs series de petits effectifs. Dans notre experience, l’efficacite de la PCE a ete observee chez 3 malades sur 7. Nous rapportons l’efficacite et la bonne tolerance de l’association methotrexate et PCE pour un malade. Conclusion Le traitement par PCE semble etre efficace chez certains malades. Il pourrait etre une alternative chez les patients pour lesquels les traitements systemiques sont contre-indiques ou se sont averes inefficaces. Toutefois cette technique necessite la proximite d’un plateau technique adapte.

Pi concentration [Pi] in the cerebrospinal fluid (CSF) is approximately half of that of plasma, suggesting that the [Pi] in the CSF is actively maintained. The membrane proteins responsible for Pi ...

Urate is a potent antioxidant at high concentrations but it has also been associated with a wide variety of health risks. Plasma urate concentration is determined by ingestion, production, and urinary excretion; however, factors that regulate urate excretion remain uncertain. The objective of this study was to determine whether cellular stress, which has been shown to affect other renal transport properties, modulates urate secretion in the avian renal proximal tubule. Chick kidney proximal tubule epithelial cell primary culture monolayers were used to study the transepithelial transport of radiolabeled urate. This model allowed examination of the processes, such as multidrug resistance protein 4 (Mrp4, Abcc4), which subserve urate secretion in a functional, intact, homologous system. Our results show that the recently implicated urate efflux transporter, breast cancer resistance protein ( ABCG2), does not significantly contribute to urate secretion in this system. Exposure to a high concentration of zinc for 6 h induced a cellular stress response and a striking decrease in transepithelial urate secretion. Acute exposure to zinc had no effect on transepithelial urate secretion or isolated membrane vesicle urate transport, suggesting involvement of a cellular stress adaptation. Activation of AMP-activated protein kinase (AMPK), a candidate modulator of ATP-dependent urate efflux, by 5′-aminoimidazole-4-carboxamide 1-β-d-ribo-furanoside caused a decrease in urate secretion similar to that seen with zinc-induced cellular stress. This effect was prevented with the AMPK inhibitor compound C. Notably, the decrease in urate secretion seen with zinc-induced cellular stress was also prevented by compound C, implicating AMPK in regulation of renal uric acid excretion.

Elastic and inelastic neutron scattering measurements have been performed on powder and single-crystal samples of orthorhombic CeRu2Al10. The order forming below T0 = 27 K was identified as a long-range antiferromagnetic state with the wave vector k = (1,0,0). The magnetic spectral response in the ordered phase, measured on powder, is characterized by a spin gap and a pronounced peak at 8 meV, whose Q dependence suggests a magnetic origin. Both features are suppressed when temperature is raised to T0, and a conventional relaxational behavior is observed at 40 K. This peculiar spin dynamics is discussed in connection with recent magnetization results for the same compound., 5 pages, 5 figures, International Conference on Heavy Electrons 2010 (Tokyo Metropolitan University, September 17 - 20, 2010), to be published in Journal of the Physical Society of Japan. Typo corrected p. 3: "sites denoted 1 and 3" => "1 and 4"

Plasma urate level is primarily regulated by urinary excretion, and ~70% of urate excretion is due to tubular secretion. Birds, which only secrete urate, and humans, which secrete and reabsorb, mai...

We report on a thorough experimental investigation of the influence of an FeO layer at the Fe/MgO interface on the magnetotransport properties in epitaxial Fe/MgO/Fe(001) magnetic tunnel junctions. Interfacial oxygen is introduced by adsorbing ${\text{O}}_{2}$ on the bottom Fe(001) layer. The morphology and composition of the FeO film are investigated by means of scanning tunneling microscopy, reflection high-energy electron diffraction, and x-ray photoelectrons spectroscopy. We show that the amount of interfacial oxygen can be precisely tuned and that either ordered or disordered FeO layers can be grown. Both Fe-O bonding and interfacial disorder strongly alter the conductances of junctions. However, the tunnel magnetoresistance remains large $(g85%)$ even for large oxygen exposure. Interfacial Fe-O bonds are found to lower the parallel conductance in agreement with theoretical predictions.

Wolbachia is a maternally inherited bacterium that is widely distributed among arthropods, in which it manipulates the reproduction of its hosts. Although generally facultative for its hosts, Wolbachia has recently become obligatory in Asobara tabida (Hymenoptera: Braconidae) in which it is required for the completion of oogenesis. Here, we describe a new Wolbachia strain (wAjap) that is associated with the genus Asobara and infects Asobara japonica. wAjap was detected in all female-biased populations of A. japonica found in the main islands of Japan, but not in the arrhenotokous populations from the southern islands. Using phylogenetic analyses based on multi-locus sequence typing (MLST), we show that this strain is closely related to wAtab3 (the strain required for oogenesis in A. tabida), even though they differ on Wolbachia surface protein (WSP) and WO phage sequences. Using antibiotic treatments, we show that cured thelytokous females are not dependent on Wolbachia for oogenesis. However, they produced only sons, showing that wAjap induces thelytokous parthenogenesis. Analyses of mating behavior and offspring production of individuals from Wolbachia-infected populations showed that while males were still sexually functional, females no longer attract males, making Wolbachia an obligate partner for daughter production in thelytokous populations. The fact that Wolbachia has become independently obligatory in two species of the same genus tends to show that dependence evolution can be common and swift, although no clear benefit for the parasitoid can be attributed to this dependence. Although dependence should lead to co-divergence between Wolbachia and its hosts, the very few cases of co-speciation observed in host-Wolbachia associations question the stability of these obligatory associations.

International audience; The influence of adsorbed oxygen at the first interface of single-crystal Fe(001)/MgO(001)/Fe(001) magnetic tunnel junctions is investigated. Firstly, the adsorption kinetics of O2 on the Fe(001) surface is studied in the monolayer regime by X-ray photoelectrons spectroscopy and scanning tunnelling microscopy experiments. We show that different species exist at the oxidized surface. The tunnel magneto-resistance of oxygen-doped magnetic tunnel junctions is found to decrease but remains large even for oxygen coverages exceeding one monolayer.

Bismuth ferrite, BiFeO3, is the only known room-temperature magnetic ferroelectric material. We demonstrate here, using neutron scattering measurements in high quality single crystals, that the antiferromagnetic and ferroelectric order parameters are intimately coupled. Initially in a single ferroelectric state, our crystals have a canted antiferromagnetic structure describing a unique cycloid. Under electrical poling, polarization reorientation induces a spin flop. We argue here that the coupling between the two orders may be stronger in the bulk than in thin films where the cycloid is absent.

We report on the antiphase boundaries network of ${\mathrm{Fe}}_{3}{\mathrm{O}}_{4}(111)$ thin films. $5\text{\ensuremath{-}}\phantom{\rule{0.3em}{0ex}}\text{to}\phantom{\rule{0.3em}{0ex}}50\text{\ensuremath{-}}\mathrm{nm}$-thick samples were epitaxially grown by molecular beam epitaxy onto $\ensuremath{\alpha}\text{\ensuremath{-}}{\mathrm{Al}}_{2}{\mathrm{O}}_{3}(0001)$ substrates. The magnetic properties of the samples have been interpreted within the framework of a one-dimensional model of antiphase boundary (APB), which predicts that the magnetization is given by ${M}_{\ensuremath{\infty}}(1\ensuremath{-}b∕\sqrt{H})$ in the approach to saturation regime. Transmission electron micrographs of several samples were used to extract the statistical parameters of the APB network, particular emphasis being put on the relevance and statistical significance of the studied parameters. The mean antiphase domain size $\overline{D}$, as the antiphase boundaries characteristic length ${l}_{0}$ extracted from a fractal analysis, vary as the square root of film thickness/deposition time and are within the $10\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ range. The APB density was found to vary as $1∕{l}_{0}$ as expected from the fractal dimensions of the network. The dependency of the $b$ parameter of the magnetic model on the APB density is finally analyzed in the light of micromagnetic simulations of chains including finite size antiphase domains and two APBs.

The discovery of giant magnetoresistance in Fe/ Cr multilayers 1 has been followed by a large research effort for almost two decades aiming at developing new materials suitable for spintronics. The interest of a given material is mainly expressed by its spin polarization P =N↑ �N↓ /N↑ +N↓, N↑ N↓ standing for majority spin minority spin electron density of states at the Fermi level. This property is particularly important for magnetic tunnel junctions stacks of two magnetic electrodes separated by a thin insulating layer. 2 Indeed, the tunnel magnetoresistance TMR, corresponding to the variation of resistance between parallel and antiparallel configurations of the electrode magnetizations, is given in a simple view by the Julliere formula: 3 TMR =2 P1P2 / 1� P1P2, P1 and P2 being the spin polarizations of the two electrodes. Magnetite Fe3O4 is thus expected to be an interesting electrode material, for band structure calculations predict a half metallic behavior P = �100%, the con

Introduction Les dermatophytes sont responsables d’atteintes de la peau glabre generalement circonscrites a l’epiderme. De rares atteintes du derme profond ont ete rapportees et se manifestent par des lesions nodulaires et pustuleuses. Nous rapportons un cas de dermatophytose profuse a Microsporum canis . Observations Un homme de 42 ans consultait pour une eruption pustuleuse prurigineuse des membres et du tronc. Il avait ete traite 3 mois auparavant par des seances de phototherapie pour un psoriasis puis de l’application de dermocorticoides. L’examen clinique mettait en evidence des lesions papulo-pustuleuses violacees, certaines de grande taille, localisees sur les membres et le tronc. Il existait egalement de discretes macules erythemateuses a centre squameux sur les bras. Il n’y avait pas d’atteinte muqueuse, ni des phaneres et aucune adenopathie palpee. Le reste de l’examen clinique etait sans particularite chez un malade en bon etat general. Nous suspections une vasculite pustuleuse ou des localisations cutanees d’une infection fongique systemique. Le bilan biologique etait normal. La biopsie cutanee mettait en evidence une lesion de folliculite aigue suppuree avec presence de filaments myceliens endo- et exothrix. Un prelevement de squame et de pustule revelait la presence de M. canis . La serologie VIH etait negative, l’electrophorese des proteines seriques etait normale et aucun antecedent n’etait en faveur d’une immunodeficience. Un traitement par griseofulvine etait introduit et permettait une evolution favorable. Parmi les animaux de l’entourage, l’infection d’un chat etait diagnostiquee et traitee. Discussion Nous rapportons un cas de dermatophytose papulo-nodulaire et pustuleuse diffuse liee a M. canis chez un patient immunocompetent. Il s’agit d’une presentation clinique rare, decrite generalement dans un contexte d’immunodeficience. Chez notre patient, une application initiale de dermocorticoides et la realisation de seances de phototherapie sont probablement responsables de la diffusion des lesions. L’agent le plus frequemment implique dans ces formes profondes est le Trichophyton rubrum . Ces formes necessitent un traitement systemique du fait de la penetration insuffisante des traitements locaux dans le derme. Conclusion Il s’agit d’une observation rapportant une forme atypique profuse de dermatophytose a M. canis chez un malade immunocompetent.

Introduction Les lesions cutanees de la maladie de Crohn (MC) metastatique sont habituellement chroniques et difficiles a traiter. Nous rapportons un cas de MC metastatique cutanee refractaire, traite avec succes par photopherese (photochimiotherapie extracorporelle). Observations Un homme de 38 ans presentait une MC severe avec localisations metastatiques cutanees. La maladie evoluait depuis l’âge de 11 ans, une colo-protectomie totale avec ileostomie definitive a l’âge de 22 ans permettait un controle digestif de la maladie. L’annee suivante, l’evolution etait marquee par l’apparition de nodules sous-cutanes et rhagades en coup de couteau, specifiques de la MC. L’anatomo-pathologie confirmait le diagnostic. Ces lesions etaient severes et invalidantes ; elles siegeaient sur la verge, aux plis inter-fessier et inguinaux. Il existait egalement une chondrite du pavillon de l’oreille. Les lesions dermatologiques demeuraient evolutives malgre les differentes lignes therapeutiques instaurees : traitements topiques (diflucortolone 0,1 %, tacrolimus 0,1 %), antibiotherapies lors de poussees inflammatoires (metronidazole, clarythromycine, pristinamycine), immunosuppresseurs (methotrexate, cyclosporine), biomedicaments anti-TNF alpha (infliximab, adalimumab). Devant l’echec des therapeutiques habituelles, une photopherese avait ete instauree : 12 seances avaient ete realisees (2 seances 2 jours de suite, repetees toutes les 2 semaines), permettant une amelioration significative et prolongee plus d’un an apres l’arret du traitement. Discussion Le traitement des lesions secondaires cutanees specifiques de la MC n’est pas codifie. La chirurgie ou les topiques sont envisageables en cas d’atteinte limitee. Dans les autres cas, plusieurs molecules ont ete proposees : la corticotherapie systemique, certains antibiotiques (metronidazole, etc.), les salicyles (sulfasalazine), les immunosuppresseurs (azathioprine, mycophenolate mofetil, cyclosporine, methotrexate), les anti-TNF alpha (infliximab, adalimumab) et le thalidomide. L’oxygenotherapie hyperbare a ete essayee chez quelques malades. D’autres travaux semblent montrer que la photopherese pourrait avoir un interet dans le traitement de la MC digestive refractaire. Les lesions cutanees sont histologiquement identiques aux lesions digestives, raison du choix de cette therapeutique dans notre cas. Il s’agit d’une technique bien toleree, n’engendrant pas d’immunosuppression ; les seules contraintes sont la necessite d’un abord veineux et la disponibilite du malade. Nous rapportons ici le premier cas de MC metastatique refractaire traite avec succes par photopherese. Conclusion La photopherese semble egalement etre efficace dans le traitement de la maladie de Crohn metastatique. Ce traitement, bien tolere, est une alternative interessante en cas d’echec des traitements classiques.

Through a few clinical case histories stemming from their daily activities at the psychiatric section of the Lantin Prison, the authors propose to revisit the classic concept of Prison psychosis. They broaden its limits to include other psychotic and dissociative phenomena common to the jail population. This requires a strict differential diagnosis, allowing to eliminate some similar pathologies; nevertheless, some difficulties and imperfections persist. The development of the psychosis, the input from the jail architecture and milieu, the predisposing as well as facilitating factors linked to the personality of the inmate, and triggering phenomena are discussed. Finally, the comorbidity between these psychotic/dissociative phenomena and the borderlinehistrionic personality disorders is envisaged.

After discussing the term "anthropologist doctor", the author describes the hard job of the psychiatrist in the penitentiary in Lantin. From the historical account of the penitentiary anthropology service, he establishes that this service has never had the necessary financial means to create and run laboratories of penitentiary anthropology, especially after the law for social defence was voted and enforced. He fears that, for want of money, the creation now of observation and treatment services would reduce the time one could spend working with prisoners in psychiatric wards. He deals briefly with the condition of psychopaths and drug-addicts in prisons.

Neutron scattering experiments using a two-dimensional detector have been performed to measure simultaneously a nuclear Bragg peak and its six surrounding magnetic satellites in a 2 μm thick (110)europium film. This technique enables the investigation of the three helical orders propagating along different directions, which gives a complete information on the magnetic configuration at a given temperature. Important variations in temperature and hysteretic effects have been observed for the magnetic population, in good agreement with a previous structural analysis. The thermal history of the film appears also to have dramatic consequences on the magnetic configurations, correlated with lattice clamping effects persisting above the magnetic ordering temperature.

We present an in-depth study of the magnetotransport properties of epitaxial Fe3O4 films as a function of film thickness. The films, grown on α-Al2O3(0001) single crystals by atomic-oxygen assisted molecular beam epitaxy, exhibit high structural order and abrupt interfaces. These films contain antiphase boundaries (APBs), the density of which is strongly dependent on film thickness. A series of resistivity and magnetoresistance measurements demonstrate a systematic evolution of these properties with decreasing film thickness, revealing the impact of APBs on the transport properties in the films. We present a model based on the spin-polarized transport across an antiferromagnetically coupled APB in order to successfully reproduce our experimental data over a large range of applied magnetic fields. The comparison of this model with experimental results further clarifies the mechanism of the anomalous magnetotransport behavior in Fe3O4.