Thermal desorption of structured water layer on epitaxial graphene

Thermal desorption of the structured water layer on graphene was observed in this study via electrical conductivity measurements. Specifically, a structured water layer was formed on the graphene surface via deionized water treatment, following which we examined the thermal desorption process of the layer using sheet resistance measurements. The water molecules acting as a p-type dopant were strongly adsorbed on graphene, forming a solid layer. Consequently, the layer was completely removed from the graphene surface at 300⁡°C. The thermal desorption spectrum of the structured water layer on graphene was quantitatively obtained by converting the measured sheet resistance to carrier density change

Urinary ACE2 in pediatric IgA nephropathy

Background : Our previous studies demonstrated that the intrarenal renin-angiotensin system (RAS) status was activated in pediatric patients with chronic glomerulonephritis. In the present study, we tested the hypothesis that angiotensin-converting enzyme 2 (ACE2) expression in the kidney is associated with the development of pediatric IgA nephropathy. Methods : We analyzed urinary ACE2 levels and ACE2 expression in the kidney tissues of pediatric patients with IgA nephropathy treated with RAS blockade. Paired tests were used to analyze changes from the first to the second biopsy. Results : Urinary ACE2 levels were significantly decreased after RAS blockade treatment, accompanied by decreased ACE2 expression levels in kidney tissues, urinary protein levels and mesangial hypercellularity scores. Urinary ACE2 levels at the first biopsy were positively correlated with the ACE2 expression levels. Conclusions : These data suggest that urinary ACE2 is associated with ACE2 expression in the diseased kidney, which correlates with the pathogenesis of IgA nephropathy in pediatric patients

Large, Negative Magnetoresistance in an Oleic Acid-Coated Fe3O4 Nanocrystal Self-Assembled Film

An oleic acid-coated Fe3O4 nanocrystal self-assembled film was fabricated via drop casting of colloidal particles on a SiO2/Si substrate. The film exhibited bifurcation of the zero-field-cooled and field-cooled magnetizations around 250 K. The nonlinear current-voltage (I–V) characteristics between the source and drain electrodes in both zero and non-zero magnetic fields (H) were observed above and below the bifurcation temperature. A large negative magnetoresistance (MR ≈ −60%) was achieved at 200 K and H = 1 T. Even at 295 K and 0.2 T, the negative MR (≈ −50%) persisted. A Fowler–Nordheim plot and power-law scaling of the I–V characteristics revealed that the current flows through two-dimensional (2D) percolated electron tunneling paths. The enlargement of MR can be attributed to spin-dependent electron tunneling between magnetically coupled Fe3O4 nanocrystals self-assembled in 2D ordered arrays

PREPARATION OF VANADIUM PENTOXIDE NANOPARTICLE-DEPOSITED ALUMINA SUBMICRON PARTICLES FOR CATALYSTS WITHOUT SINTERING

The formation of vanadium pentoxide (V₂O₅) nanoparticles immobilized on alumina (Al₂O₃) particles was studied in a methane/oxygen coflow diffusion-flame reactor. V₂O₅ nanoparticles formed by the decomposition of vanadium oxytriethoxide were deposited onto Al₂O₃ particles, which were introduced into the flame together with vanadium oxytriethoxide solution. To immobilize the V₂O₅ nanoparticles on Al₂O₃ particles, rapid cooling with a Laval nozzle was applied to the V₂O₅/Al₂O₃ particles formed in the flame. We found that it was possible to suppress the sintering of V₂O₅ nanoparticles on the Al₂O₃ particles when the Al₂O₃ particles were introduced into the flame at a temperature sufficiently high to soften the surfaces of the Al₂O₃ particles

Magnetic and magnetoelectric properties of self-assembled Fe2.5Mn0.5O4 nanocrystals

We report magnetoresistance of 40%, corresponding to 80% spin polarization, at magnetic field of 0.5 T and 200 K for oleic acid-coated Fe2.5Mn0.5O4 nanocrystals (FMO NCs) self-assembled on a SiO2/Si substrate by drop casting fabrication. TheFMONCs exhibited spin glass transition around 150 K and nonlinear current voltage (I V) characteristics. Fowler Nordheim plot of the I V characteristics indicated that electrons tunnel directly barriers between the FMO NCs. Transmission electron microscopy revealed that the FMO NCs are elongated hexagon in shape with size of ∼15 20 nm. The FMO NCs self-assembled in two-dimension hexagonal networks of collinear ferromagnetic moments. The [111] easy magnetization axis of each FMO NC was parallel to each other in the hexagonal arrays. Geometrically frustrated lattice of collinear ferromagnetic moments supports both a low and a high intergranular tunneling conductance for the self-assembled FMO NCs without and with magnetic fields, respectively

Clinical significance of nuclear non-phosphorylated beta-catenin in acute myeloid leukaemia and myelodysplastic syndrome

Wnt signaling activates the canonical pathway and induces the accumulation of non-phosphorylated beta-catenin (NPBC) in the nucleus. Although this pathway plays an important role in the maintenance of haematopoietic stem cells as well as in oncogenesis, the significance of nuclear NPBC remains unclear in malignant haematopoiesis. This study examined the expression of nuclear NPBC in bone marrow specimens from 54 and 44 patients with de novo acute myeloid leukaemia (AML) and myelodysplastic syndrome (MDS), respectively. On immunohistochemistry with an anti-NPBC antibody, the nuclei were positively stained in 22 and 18 of AML and MDS specimens, respectively. Staining of nuclear NPBC was associated with AML subtypes (M6 and M7), low complete remission (CR) rate, and poor prognosis. Nuclear NPBC was also associated with a high score when using the International Prognostic Scoring System (IPSS) for MDS and with −7/−7q and complex karyotypes. These findings suggest that in situ detection of nuclear NPBC by immunohistochemistry could provide new insights into the pathogenesis and prognosis of AML and MDS