Hall Resistivity in Ferromagnetic Manganese-Oxide Compounds

Temperature-dependence and magnetic field-dependence of the Hall effect and the magnetic property in manganese-oxide thin films are studied. The spontaneous magnetization and the Hall resistivity are obtained for a various of magnetic fields over all the temperature. It is shown that the Hall resistivity in small magnetic field is to exhibit maximum near the Curie point, and strong magnetic field moves the position of the Hall resistivity peak to much high temperature and suppresses the peak value. The change of the Hall resistance in strong magnetic field may be larger than that of the diagonal ones. The abnormal Hall resistivity in the ferromagnetic manganese-oxide thin-films is attributed to the spin-correlation fluctuation scattering.Comment: Latex, 2 Figures, 10 Page

Chrysin suppresses lipopolysaccharide-induced cyclooxygenase-2 expression through the inhibition of nuclear factor for IL-6 (NF-IL6) DNA-binding activity

AbstractChrysin is a natural, biologically active compound extracted from many plants, honey and propolis. It possesses potent anti-inflammation, anti-cancer and anti-oxidation properties. The mechanism by which chrysin suppresses COX-2 expression remains poorly understood. In the present report, we investigated the effect of chrysin on the expression of COX-2 in lipopolysaccharide (LPS)-activated Raw 264.7 cells. Chrysin significantly suppressed the LPS-induced COX-2 protein and mRNA expression in a dose-dependent manner. The ability of chrysin to suppress the expression of the COX-2 was investigated using luciferase reporters controlled by various cis-elements in COX-2 promoter region. Mutational analysis and electrophoretic mobility shift assay verified that nuclear factor for IL-6 was identified as responsible for the chrysin-mediated COX-2 downregulation. These results will provide new insights into the anti-inflammatory and anti-carcinogenic properties of chrysin

Isotropic photonic band gap and anisotropic structures in transmission spectra of two-dimensional 5-fold and 8-fold symmetric quasiperiodic photonic crystals

We measured and calculated transmission spectra of two-dimensional quasiperiodic photonic crystals (PCs) based on a 5-fold (Penrose) or 8-fold (octagonal) symmetric quasiperiodic pattern. The photonic crystal consisted of dielectric cylindrical rods in air placed normal to the basal plane on vertices of tiles composing the quasiperiodic pattern. An isotropic photonic band gap (PBG) appeared in the TM mode, where electric fields were parallel to the rods, even when the real part of a dielectric constant of the rod was as small as 2.4. An isotropic PBG-like dip was seen in tiny Penrose and octagonal PCs with only 6 and 9 rods, respectively. These results indicate that local multiple light scattering within the tiny PC plays an important role in the PBG formation. Besides the isotropic PBG, we found dips depending on the incident angle of the light. This is the first report of anisotropic structures clearly observed in transmission spectra of quasiperiodic PCs. Based on rod-number and rod-arrangement dependence, it is thought that the shapes and positions of the anisotropic dips are determined by global multiple light scattering covering the whole system. In contrast to the isotropic PBG due to local light scattering, we could not find any PBGs due to global light scattering even though we studied transmission spectra of a huge Penrose PC with 466 rods.Comment: One tex file for manuscript and 12 PNG files for figures consisting of Fig.1a-d, 2,3, ...

Scanning Tunneling Microscopy Measurements of the Local Work Function around Steps on the Au/Cu(111) Surface(STM-local states)

With a scanning tunneling microscope we have taken local work function images of the Au/Cu(111) surface. The local work function measured from large Au-covered terraces is in good agreement with the result obtained by non-local techniques, and the local work function around step edges is significantly lower than that on terraces. The experimental details of the local work function lowering around a step can be reproduced nicely with a simple simulation if a dipole moment row with a proper linear density is put at the center of the step and if the influence of the topographic change of the step due to formation of the dipole moment is taken into account. It is demonstrated that STM has the ability to reveal the details of how local work function varies around steps and other defects on metal surfaces

On the sample size dependence of the critical current density in MgB2_2 superconductors

Sample size dependent critical current density has been observed in magnesium diboride superconductors. At high fields, larger samples provide higher critical current densities, while at low fields, larger samples give rise to lower critical current densities. The explanation for this surprising result is proposed in this study based on the electric field generated in the superconductors. The dependence of the current density on the sample size has been derived as a power law $j\propto R^{1/n}$ ($n$ is the $n$ factor characterizing $E-j$ curve $E=E_c(j/j_c)^n$). This dependence provides one with a new method to derive the $n$ factor and can also be used to determine the dependence of the activation energy on the current density.Comment: Revtex, 4 pages, 5 figure

Analysis of Infant Microbiota Composition and the Relationship With Breast Milk Components in the Asian Elephant (Elephas Maximus) at the Zoo

The prevention of diseases through health control is essential at zoos. Here, we investigated the gut microbiota formation during infancy in an Asian elephant and compared the composition between infant and mother. Besides, we analyzed the components of breast milk and examined the correlation with the infant gut microbiota. Analysis revealed the gut microbiota of the infant contained high amount of Lactobacillales and its diversity was relatively low compared to that of the mother. We found several milk components, showed a positive correlation with the change of Lactobacillales. The present study revealed the mechanism of gut microbiota formation during infancy in an Asian elephant and provides important insights into the health control of Asian elephants in zoos

Detection of Lung Cancer Cells in Solutions Using a Terahertz Chemical Microscope

Cancer genome analysis has recently attracted attention for personalized cancer treatment. In this treatment, evaluation of the ratio of cancer cells in a specimen tissue is essential for the precise analysis of the genome. Conventionally, the evaluation takes at least two days and depends on the skill of the pathologist. In our group, a terahertz chemical microscope (TCM) was developed to easily and quickly measure the number of cancer cells in a solution. In this study, an antibody was immobilized on a sensing plate using an avidin-biotin reaction to immobilize it for high density and to improve antibody alignment. In addition, as the detected terahertz signals vary depending on the sensitivity of the sensing plate, the sensitivity was evaluated using pH measurement. The result of the cancer cell detection was corrected using the result of pH measurement. These results indicate that a TCM is expected to be an excellent candidate for liquid biopsies in cancer diagnosis

Meson-baryon sigma terms in QCD Sum Rules

We evaluate the pion-nucleon and the pion-Delta sigma terms by employing the method of quantum chromodynamics (QCD) sum rules. The obtained value of the pion-nucleon sigma term is compatible with the larger values already anticipated by the recent calculations. It is also found that the pion-Delta sigma term is as large as the pion-nucleon sigma term.Comment: 14 pages, 2 figures; extended discussion and added references; version to be published in Phys. Lett.