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Yersinia pseudotuberculosiscan replicate inside macrophages by hijacking autophagy and blocking autophagosome acidification. In bone marrow-derived macrophages, the bacteria are mainly observed inside double-membrane vacuoles positive for LC3, a hallmark of autophagy. Here, we address the question of the membrane traffic during internalization of Yersiniainvestigating the role of vesicle- associated membrane proteins (VAMPs). First, we show that as in epithelial cells, Yersinia pseudotuberculosisreplicates mainly in nonacidic LC3-positive vacuoles. Second, in these cells, we unexpectedly found that VAMP3 localizes preferentially to Yersinia-containing vacuoles (YCVs) with single membranes using correlative light-electron microscopy. Third, we reveal the precise kinetics of VAMP3 and VAMP7 association with YCVs positive for LC3. Fourth, we show that VAMP7 knockdown alters LC3′s association with single-and multimembrane-YCVs. Finally, in uninfected epithelial cells stimulated for autophagy, VAMP3 overexpression and knockdown led respectively to a lower and higher number of double-membrane, LC3-positive vesicles. Hence, our results highlight the role that VAMPs play in selection of the pathways leading to generation of ultrastructurally different LC3 compartments and pave the way for determining the full set of docking and fusion proteins involved in Yersinia pseudotuberculosis’ intravesicular life cycle.

The vibrational properties of β-SnWO4at center of the Brillouin zone are investigated by Raman at low temperature and infrared spectroscopies in connexion with ab initio calculations. In this cubic structure archetype of new materials with ionic conductivity properties, all 29 optical modes predicted by group theory are Raman-active. All lines have been unambiguously identified on the basis of depolarization ratio measurements. The phonon spectrum is calculated at the center of the Brillouin zone by GGA pseudopotentials within the PWSCF/QE suite. A remarkable agreement is obtained with the experimental frequencies, and a fairly good one is also observed with the Raman scattering cross sections calculated using LDA pseudopotentials for the internal modes of WO42–tetrahedra and the lattice modes as well. All Raman lines are assigned for the first time, and the normal coordinates characteristics are described. The whole results give a large credit to the calculation of the phonon spectra in this structural arrangement with such ions. The phonon density of states is deduced, and the characteristics are explained on the basis of the phonon dispersions curves along the [ξ00] and [ξξ0] high-symmetry directions of the Brillouin zone.

Rapid blood perfusion is critical for postimplantation survival of thick, prevascularized bioartificial tissues. Yet the mechanism by which implanted vascular networks inosculate, or anastomose, with the host vasculature has been unknown, making it difficult to develop optimized strategies for facilitating perfusion. Here we show that implanted vascular networks anastomose with host vessels through a previously unidentified process of “wrapping and tapping” between the engrafted endothelial cells (ECs) and the host vasculature. At the host-implant interface, implanted ECs first wrap around nearby host vessels and then cause basement membrane and pericyte reorganization and localized displacement of the underlying host endothelium. In this way, the implanted ECs replace segments of host vessels to divert blood flow to the developing implanted vascular network. The process is facilitated by high levels of matrix metalloproteinase-14 and matrix metalloproteinase-9 expressed by the wrapping ECs. These findings open the door to new strategies for improving perfusion of tissue grafts and may have implications for other physiologic and pathologic processes involving postnatal vasculogenesis.

Native tissue cystocele repair has been the cornerstone of prolapse surgery, especially since the learned societies warned clinicians and patients about serious mesh related complications and recommend a vaginal route without prosthesis in first intention. Surgical techniques mainly consist in anterior colporraphy, vaginal patch plastron and para vaginal repair. However, in case of vaginal patch plastron, the vagina left in contact with the bladder is a material of much better quality than colporraphy alone. The multiplication of native tissues, generating post-operative fibrosis, associated with anchorage on a strong ligamentous structure, allows to expect better outcomes compared to anterior colporraphy. Indeed, vaginal plastron corrects median cystoceles with a vaginal strip as well as lateral cystoceles thanks to bilateral paravaginal suspension. Thereby, vaginal patch plastron appears to be a good compromise between the 3 autologous techniques with median and paralateral repair

Demixing/recombination and metastability phenomena are observed in the La2–2xCa2xMo2O9–x solid solutions ofLAMOX-type fast oxide-ion conductors (0.005 ≤ x ≤ 0.05). The demixing process is more visible at high Ca content. The effects of composition, sample shape (powders with twodegrees of fineness, ceramic pellets, single crystals) and thermal history are studied by using high-temperature X-ray diffraction, differential scanning calorimetry (DSC) and polarized microscopy. All these parameters are shown to have an influence on the stability of, and transformations between, the ordered α and the disordered β forms of the LAMOX compounds. Powder samples with low Ca content (x = 0.01, 0.02) have been stabilized in the α form, and powder samples with higher Ca content (x = 0.03, 0.04, 0.05) are in the β form. Upon heating, the low-Ca-content compounds (x = 0.01 and x = 0.02) exhibit the α/β transition, whereas those with higher Ca content (x = 0.03 and x = 0.04) show a succession of β/α/β phase transformations (metastability of the β form). The compound with the highest Ca content (x = 0.05) remains in the β form over the whole thermal range. Upon cooling, all samples exhibit the β/α phase transition. When x = 0.04, powder annealing suppresses all the phase transformations upon heating, but not the β/α transition upon cooling, whereas sample shaping/sintering as a pellet stabilizes the β form over the whole thermal range upon heating and cooling. Single crystals with compositions x = 0.005 and x = 0.025 can be obtained either in the α or in the β form by slow cooling or by quenching, respectively. In these oxide-ion conductors with a high concentration of point defects, internal or external stress appears to strongly affect the vacancy equilibrium but not the demixing/recombination phenomenon.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

The effects of partial substitutions of Bi by La, Gd, and Y on the structure, thermal expansion and transport properties of modulated fluorite-type Bi5NbO10were investigated using X-ray thermodiffraction, alternative current impedance spectroscopy and the Wagner polarization method. Through conventional solid-state syntheses, the solid solutions Bi5−xLnxNbO10exist up to about x∼ 0.25 for La, and to x∼ 0.5 for Gd and Y. A doubling of their thermal expansion coefficient is observed above 540 °C. The type-II incommensurate modulation of these phases is correlated to the nature and amount of substitute, and disappears above 800 °C. Except for Bi5NbO10, which appears to be a pure ionic conductor, most of the solid solutions exhibit mixed conductivity with predominant ionic transport. Partial Gd and Y substitutions favor electron conductivity in the low temperature range, probably due to bismuth partial oxidation.

Endothelial cells display remarkable heterogeneity in different organs and vascular beds. Although many studies suggest that tissues “speak” to endothelial cells, endothelial cell diversity remains poorly characterized at the molecular level. Here, we describe a novel strategy to characterize tissue-specific endothelial cell phenotypes and to identify endothelial cell genes that are under the control of the local microenvironment. By comparing post-capillary high endothelial venule endothelial cells (HEVECs), freshly isolated from human tonsils without any cell culture step, with HEVECs cultured for 2 days, we found that HEVECs rapidly lost their specialized characteristics when isolated from the lymphoid tissue microenvironment. Striking changes occurred as early as after 48 hours, with complete loss of the postcapillary venule–specific Duffy antigen receptor for chemokines (DARCs) and the HEV-specific fucosyltransferase Fuc-TVII. DNA microarray analysis identified several other candidate HEV genes that were rapidly down-regulated ex vivo, including type XV collagen, which we characterized as a novel, abundant HEV transcript in situ. Together, our results demonstrate that blood vessel type–specific and tissue-specific characteristics of endothelial cells are under the control of their microenvironment. Therefore, even short-term primary cultures of human endothelial cells may not adequately mimic the differentiated endothelial cell phenotypes existing in vivo.

A series of optimised materials in the family with parent compound La₂Mo₂O₉ have been studied using the isotope exchange depth profile technique and SIMS analysis. The data collected indicate that the oxide ion diffusion coefficients in both the parent compound and optimised materials are significantly higher than those reported for any of the fluorite structured electrolyte materials, with a peak value for the La_1.7Gd_0.3Mo₂O₉ composition of 1.41 × 10−6 cm2 s−1 at 800 °C. Further, it was found that the substitution of isotopic oxygen into the ceramic was limited in dry atmospheres but significantly enhanced in a H₂18O/16O atmosphere, in common with recent reports on the diffusion/exchange behaviour of the BIMEVOX class of oxide ion conductors.

The substitutional range and cell parameter evolution of fast oxide-ion conductors La_2−xR_xMo_2−yW_yO₉ (R = Nd, Gd) are investigated. In the whole series, the cubic β-La₂Mo₂O₉ structural type is stabilized at room temperature. The effects on reducibility of both single and double substitutions are presented. Lanthanum substitution by rare earth appeared to be responsible for an increase in the reducibility and a strong but reversible amorphization under dilute hydrogen. On the contrary, the favourable role of tungsten on the compound stability under reducing conditions is evidenced: it depletes oxygen loss while making the La₂Mo₂O₉ structural type less affected by it.

The substitutional range and cell parameter evolution of fast oxide-ion conductors La2−xRxMo2−yWyO9R Nd, Gd are investigated. In the whole series, the cubic β-La2Mo2O9structural type is stabilized at room temperature. The effects on reducibility of both single and double substitutions are presented. Lanthanum substitution by rare earth appeared to be responsible for an increase in the reducibility and a strong but reversible amorphization under dilute hydrogen. On the contrary, the favourable role of tungsten on the compound stability under reducing conditions is evidenced: it depletes oxygen loss while making the La2Mo2O9structural type less affected by it.

Fluorine-doped lanthanum molybdates with the nominal formula La2Mo2O9-0.5xFx (x = 0.20−0.30) were synthesized and characterized using powder X-ray diffraction, electron diffraction, differential thermal analysis, and impedance spectroscopy. Comparisons are made with the parent anionic conductor system La2Mo2O9. From our studies two distinct regimes with two different ranges of “x” values (range 1:  including 0.00 ≤ x ≤ 0.12; range 2:  including 0.18 ≤ x ≤ 0.30) could be delineated for the La2Mo2O9-0.5xFx compositions. Electron diffraction study on selected samples showed that x = 0.20 and 0.30 compositions (range 2) have a 3 × 3 × 3 supercell, different from the 2 × 3 × 4 supercell observed in the x = 0.00 and 0.10 compositions (range 1). All the fluorine-doped lanthanum molybdates show a first-order phase transition. With the increase in the fluorine content the transition temperature decreases in both ranges 1 and 2. Below the transition temperature, compositions belonging to range 2 have much lower conductivity when compared to that of those belonging to range 1. The activation energy as obtained from the conductivity data is higher for the fluorine-doped lanthanum molybdates compared to the parent compound La2Mo2O9. Above the transition temperature the conductivity of the fluorine-doped lanthanum molybdate is higher than that of La2Mo2O9. Significantly our study presents the possibility of using fluorine substitution as a technique to increase the anionic conductivity in oxide ion conductors with favorable structural features (like in the case of La2Mo2O9) by decreasing the transition temperature of the first-order (order−disorder type) phase transition.

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The structure of La2Mo4O15has been determined from both high resolution X-ray and neutron powder diffraction data. This molybdate crystallizes in a monoclinic space group P21/nwith cell parameters a=9.0357(2) Å, b=12.7737(2) Å, c=10.6408(2) Å, β=90.2491(6)°. The structure consists of molybdenum octahedra [MoO6] and tetrahedra [MoO], and lanthanum polyhedra [LaO9]. Molybdenum polyhedra are connected together, forming large units [Mo6O22], isolated by lanthanum polyhedral chains. This structure is compared with those of already known lanthanide molybdates with formula Ln2Mo4O15(Ln=Ce, Ho).

A new family of fast O²⁻ conductors, which exhibit anionic conductivity comparable to that of stabilised zirconia, is presented. The parent compound of this new family, hereafter called LAMOX, is lanthanum molybdate La₂Mo₂O₉. Various substitutions have been attempted: on the lanthanum site (La_{2 − x}A_x)Mo₂O₉ with A = Sr, Ba, K, or Bi; on the molybdenum site La₂(Mo_{2 − x}B_x)O₉ with B = Re, S, W, Cr and V; and on the oxygen site with fluorine. Most of these substitutions suppress the phase transition which occurs in La₂Mo₂O₉ around 580 °C from a low temperature α form to a high temperature (more conducting) β form, and stabilise the β form at room temperature. Several members of the LAMOX series are studied through X-ray and neutron diffraction, and conductivity measurements. Large O²⁻ thermal factors and local static disorder agree well with the anionic nature of the conductivity. Partly vacant sites with short inter-site distances suggest a most probable conduction path with tridimensional character.

The microstructure of NdNiO$_3$ thin films deposited on Si (100) has been investigated by high resolution electron microscopy. Deposition at 250 $^{\circ}$C and 600 $^{\circ}$C and several annealing at high temperature under oxygen pressure were performed. Depending on the deposition temperature and annealing conditions, different texture and microstructure were observed. Relationships between microstructure and transport properties are discussed. The differences of grain boundaries are suggested to be responsible for the difference in transport properties of the films.

The coronavirus SARS-CoV-2 (COVID-19) pandemic has put tremendous pressure on the French healthcare system. Almost all hospital departments have had to profoundly modify their activity to cope with the crisis. In this context, the surgical management of cancers has been a topic of debate as care strategies were tailored to avoid any delay in treatment that could be detrimental to patient wellbeing while being careful not to overload intensive care units.

Thallium metaniobate, Tl2Nb2O6, belongs to the cubic pyrochlore structural type (space group Fd3m). It is demonstrated by TGA, chemical analysis, and X-ray thermodiffractometry that it gives a continuous solid solution Tl2Nb2O6+x(0 ≤ x≤ 1) under oxidation; the cubic pyrochlore structure is maintained with a continuous decreasing unit cell edge: xoxide ions being progressively incorporated into the network while xTl3+ions substitute to xTl+ones. Rietveld refinements of X-ray powder diffraction data reveal that, in the classical model of the pyrochlore structure, Tl+and Tl3+are disordered on half of the 32epositions for 0 ≤ x< 0.5 and on the 16dones for 0.5 < x≤ 1. Bond valence calculations are in good agreement with the decrease in the splitting of Tl cations from 32eto 16dpositions when xincreases, provided that a correlation exists between oxygen insertion and the Tl3+distribution: each extra oxygen O' oxidizes one of its closest Tl neighbors to +3 while the three remaining monovalent Tl cations are repelled.

The crystal structure of κ-alumina (κ-Al2O3) has been determined ab initio from an X-ray powder diffraction pattern (reliability factors: RBragg=0.046, Rp=0.090, Rwp=0.115, χ2=11.7). The acentric structure (orthorhombic system, space group Pna21 , a=4.8437(2) Å, b=8.3300(3) Å, c=8.9547(4) Å, Z=8) is built up from a pseudo-close-packed stacking ABAC of oxygen atoms, with aluminium in octahedral and tetrahedral environments in a 3:1 ratio, which form zigzag ribbons of edge-sharing octahedra and corner-sharing tetrahedra. κ-Alumina was characterized using magic angle spinning (MAS) 27Al NMR at two fields and multiple quantum magic angle spinning (3Q MQ MAS) 27Al NMR. A high-resolution electron microscopy study confirmed the structure and showed the presence of two types of defects: antiphase boundaries and 120 ° disorientations. A model is proposed for these two types of defects, which leaves unchanged the pseudo-close-packed arrangement of the oxygen atoms and assumes a shift or 120 ° twinning of aluminium ions.

Ga3P3O12F2, H3N(CH2)3NH3, H2O was obtained by hydrothermal synthesis (453 K, 24 hr, autogeneous pressure) from a mixture of Ga2O3, P2O5, HF, 1,3-diaminopropane, and H2O in the ratio 1:1:2:1.3:80. It is orthorhombic (space group Pbca(No. 61) with a= 10.154(1)Å, b= 18.393(2)Å, c= 15.773(2) Å, V= 2945.8(9) Å, Z= 8. The three-dimensional network is built up from corner-linked [Ga3(PO4)3F2] units composed of three PO4tetrahedra, two GaO4F trigonal bipyramids, and one GaO4F2octahedron. Fluorine atoms are shared between the octahedron and the bipyramid. The framework delimits 10-membered ring channels along [100] and 8-membered ones along [101] and [10-1]. The amine and the water molecule are inserted in the 10-membered ring channels. The hydrogen bonding scheme is discussed and shows that the water is principally linked to the amine within the tunnel and that the template might be the amine monohydrate. The thermal behavior of the title compound is studied by TGA and X-ray thermodiffractometry.

Fe3+1.21PO4X(X= F-, OH-, H2O), obtained by hydrothermal synthesis (200°C, 6 days) from a 1:1:2:40 mixture of Fe(NO3)3(H2O)9, P2O5, NH4F, H2O, is tetragonal (S.G. = I41/amd(No. 141)), a= 5.184(1) Å, c= 13.040(5) Å, V= 350.4(3) Å3, Z= 4. Its structure, isotypic with those of Lipscombite, Fe2-δPO4(OH), and 3MgSO4, Mg(OH)2, H2O, is built up from the interconnection of chains of face sharing anionic octahedra (5 × 14 Å2structure type). The partial occupancy, close to 23, of these octahedra by Fe3+is discussed. Antiferromagnetism (TN= 81 K) of Fe1.21PO4Xwas characterized by susceptibility measurements and Mössbauer spectroscopy. The magnetic behavior is analyzed in relation with the two types of disorder (vacancies and nature of X) occuring in the chains.

A study of the stability of classical systems under the influence of two conflicting single-well, single-variable potentials is presented. The control parameters are a so-called conflict parameter c, the distance between the two conflicting attractors, and an asymmetry parameter a which determines the relative strength of the two attractors. For convex potentials, the influence of conflict on the system stability depends on the sign of the third derivative of the conflicting potential functions, resulting in two categories called U- and V-type potentials. The introduction of a concave branch (bias) in convex conflicting potentials qualitatively changes the system behavior, by generating bifurcation and discontinuity. The cusp catastrophe can be redefined as the conflict between two such biased single-well potentials. The main interest of the new representation potentially lies in the evocative power of the control parameters a and c. The mapping of (a,c) on (u,v), the traditional control parameters of the cusp catastrophe, is given. The cusp develops above a certain critical value of the conflict parameter c.

The electronic properties of transition-metal oxides with highly correlated electrons are of central importance in modern condensed-matter physics and chemistry, both for their fundamental scientific interest and for their potential for advanced electronic applications. However, the design of materials with tailored properties has been restricted by the limited understanding of their structure–property relationships, which are particularly complex in the proximity of the regime where localized electrons become gradually mobile. RENiO3perovskites, characterized by the presence of spontaneous metal to insulator transitions, are some of the most widely used model materials for the investigation of this region in theoretical studies. However, crucial experimental information needed to validate theoretical predictions is still lacking due to their challenging high-pressure synthesis, which has prevented to date the growth of sizable bulk single crystals with RE ≠ La, Pr, and Nd. Here we report the first successful growth of single crystals with RE = Nd, Sm, Gd, Dy, Y, Ho, Er, and Lu in sizes up to ∼75 μm, grown from molten salts in a temperature gradient under 2000 bar of oxygen gas pressure. The crystals display regular prismatic shapes with flat facets, and their crystal structures and metal–insulator and antiferromagnetic order transition temperatures are in excellent agreement with previously reported values obtained from polycrystalline samples. The availability of such crystals opens access to measurements that have hitherto been impossible to conduct. This should contribute to a better understanding of the fascinating properties of materials with highly correlated electrons and guide future efforts to engineer transition-metal oxides with tailored functional properties.

•A three-half-day training session in robotic surgery for gynecology is feasible and safe.•Trainees consider dual console helpful and reassuring.•This training seems to be reproductible for other university teaching centers.