104 research outputs found
BiFeO3/La0.7Sr0.3MnO3 heterostructures deposited on Spark Plasma Sintered LaAlO3 Substrates
Multiferroic BiFeO3 (BFO) / La0.7Sr0.3MnO3 heterostructured thin films were
grown by pulsed laser deposition on polished spark plasma sintered LaAlO3 (LAO)
polycrystalline substrates. Both polycrystalline LAO substrates and BFO films
were locally characterized using electron backscattering diffraction (EBSD),
which confirmed the high-quality local epitaxial growth on each substrate
grain. Piezoforce microscopy was used to image and switch the piezo-domains,
and the results are consistent with the relative orientation of the
ferroelectric variants with the surface normal. This high-throughput synthesis
process opens the routes towards wide survey of electronic properties as a
function of crystalline orientation in complex oxide thin film synthesis.Comment: 10 pages, 4 figures, Submitted to Applied Physics Letter
Growth and texture of Spark Plasma Sintered Al2O3 ceramics: a combined analysis of X-rays and Electron Back Scatter Diffraction
Textured alumina ceramics were obtained by Spark Plasma Sintering (SPS) of
undoped commercial a-Al2O3 powders. Various parameters (density, grain growth,
grain size distribution) of the alumina ceramics, sintered at two typical
temperatures 1400{\deg}C and 1700{\deg}C, are investigated. Quantitative
textural and structural analysis, carried out using a combination of Electron
Back Scattering Diffraction (EBSD) and X-ray diffraction (XRD), are represented
in the form of mapping, and pole figures. The mechanical properties of these
textured alumina ceramics include high elastic modulus and hardness value with
high anisotropic nature, opening the door for a large range of applicationsComment: 16 pages, 6 figures, submitted to J. Appl. Phy
Human Cytomegalovirus IE1 Protein Elicits a Type II Interferon-Like Host Cell Response That Depends on Activated STAT1 but Not Interferon-γ
Human cytomegalovirus (hCMV) is a highly prevalent pathogen that, upon primary
infection, establishes life-long persistence in all infected individuals. Acute
hCMV infections cause a variety of diseases in humans with developmental or
acquired immune deficits. In addition, persistent hCMV infection may contribute
to various chronic disease conditions even in immunologically normal people. The
pathogenesis of hCMV disease has been frequently linked to inflammatory host
immune responses triggered by virus-infected cells. Moreover, hCMV infection
activates numerous host genes many of which encode pro-inflammatory proteins.
However, little is known about the relative contributions of individual viral
gene products to these changes in cellular transcription. We systematically
analyzed the effects of the hCMV 72-kDa immediate-early 1 (IE1) protein, a major
transcriptional activator and antagonist of type I interferon (IFN) signaling,
on the human transcriptome. Following expression under conditions closely
mimicking the situation during productive infection, IE1 elicits a global type
II IFN-like host cell response. This response is dominated by the selective
up-regulation of immune stimulatory genes normally controlled by IFN-γ and
includes the synthesis and secretion of pro-inflammatory chemokines.
IE1-mediated induction of IFN-stimulated genes strictly depends on
tyrosine-phosphorylated signal transducer and activator of transcription 1
(STAT1) and correlates with the nuclear accumulation and sequence-specific
binding of STAT1 to IFN-γ-responsive promoters. However, neither synthesis
nor secretion of IFN-γ or other IFNs seems to be required for the
IE1-dependent effects on cellular gene expression. Our results demonstrate that
a single hCMV protein can trigger a pro-inflammatory host transcriptional
response via an unexpected STAT1-dependent but IFN-independent mechanism and
identify IE1 as a candidate determinant of hCMV pathogenicity
Mise au point de méthodes permettant la détection d'organismes génétiquement modifiés (OGM) dans les grains et les produits transformés
National audienc
Growth and texture of spark plasma sintered Al 2 O 3 ceramics: A combined analysis of X-rays and electron back scatter diffraction
International audienceTextured alumina ceramics were obtained by Spark Plasma Sintering (SPS) of undoped commercial a-Al2O3 powders. Various parameters (density, grain growth, grain size distribution) of the alumina ceramics, sintered at two typical temperatures 1400°C and 1700°C, are investigated. Quantitative textural and structural analysis, carried out using a combination of Electron Back Scattering Diffraction (EBSD) and X-ray diffraction (XRD), are represented in the form of mapping, and pole figures. The mechanical properties of these textured alumina ceramics include high elastic modulus and hardness value with high anisotropic nature, opening the door for a large range of application
From hypotonic maintenance fluid to severe hyponatremia: a case report
Abstract Background The principles for maintenance intravenous fluid prescription in children were developed in the 1950s. These guidelines based on the use of hypotonic solutions have been challenged regularly for they seem to be associated with an increased risk of hospital-acquired hyponatremia. Case presentation We report the case of a 4-week-old Caucasian child admitted for acute bronchiolitis who received hypotonic maintenance fluids and developed severe hyponatremia (94 mmol/L) with hyponatremic encephalopathy. Conclusion This clinical situation can serve as a reminder of the latest recommendations from the American Academy of Pediatrics regarding the use of intravenous fluids that promote the use of isotonic fluids in children
Growth and texture of spark plasma sintered Al 2 O 3 ceramics: A combined analysis of X-rays and electron back scatter diffraction
International audienceTextured alumina ceramics were obtained by Spark Plasma Sintering of undoped commercial α-Al2O3 powders. Various parameters (density, grain growth, grain size distribution) of the alumina ceramics, sintered at two typical temperatures 1400 °C and 1700 °C, are investigated. Quantitative textural and structural analysis, carried out using a combination of Electron Back Scattering Diffraction and X-ray diffraction, are represented in the form of mapping and pole figures. The mechanical properties of these textured alumina ceramics include high elastic modulus and hardness values with high anisotropic nature, opening the door for a large range of applications
BiFeO3/La0.7Sr0.3MnO3 heterostructures deposited on spark plasma sintered LaAlO3 substrates
International audienceMultiferroic BiFeO3 (BFO)/La0.7Sr0.3MnO3 heterostructured thin films were grown by pulsed laser deposition on polished spark plasma sintered LaAlO3 (LAO) polycrystalline substrates. Both polycrystalline LAO substrates and BFO films were locally characterized using electron backscattering diffraction, which confirmed the high-quality local epitaxial growth on each substrate grain. Piezoforce microscopy was used to image and switch the piezo-domains, and the results are consistent with the relative orientation of the ferroelectric variants with the surface normal. This high-throughput synthesis process opens the routes towards wide survey of electronic properties as a function of crystalline orientation in complex oxide thin film synthesis
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