Improved accuracy in high-frequency AC transport measurements in pulsed high magnetic fields.

We show theoretically and experimentally that accurate transport measurements are possible even within the short time provided by pulsed magnetic fields. For this purpose, a new method has been devised, which removes the noise component of a specific frequency from the signal by taking a linear combination of the results of numerical phase detection using multiple integer periods. We also established a method to unambiguously determine the phase rotation angle in AC transport measurements using a frequency range of tens of kilohertz.

Spin-chirality-driven ferroelectricity on a perfect triangular lattice antiferromagnet.

Magnetic field (B) variation of the electrical polarization P(c) (∥c) of the perfect triangular lattice antiferromagnet RbFe(MoO(4))(2) is examined up to the saturation point of the magnetization for B⊥c. P(c) is observed only in phases for which chirality is predicted in the in-plane magnetic structures. No strong anomaly is observed in P(c) at the field at which the spin modulation along the c axis, and hence the spin helicity, exhibits a discontinuity to the commensurate state.

High mortality rate of (NZW x BXSB)F1 mice induced by administration of lipopolysaccharide attributes to high production of tumour necrosis factor-alpha by increased numbers of dendritic cells.

(NZW x BXSB)F1 mice (W/BF1 mice) have been reported to be a type of autoimmune-prone mice, showing symptoms of proteinuria, anti-DNA antibodies and anti-platelet antibodies. In this paper, we report that W/BF1 mice show hyperproduction of tumour necrosis factor (TNF)-alpha, responding to lipopolysaccharide (LPS) in comparison with normal mice, resulting in induction of death. In normal mice, monocytes/macrophages (Mo/MØ) are the main producer of TNF-alpha, while both Mo/MØ and dendritic cells (DCs) produce TNF-alpha in W/BF1 mice.

Data base and management system for clinical positron emission tomography (PET) studies.

A data base and management system connected to an image analysis system has been developed and utilized for clinical positron emission tomography (PET). This data base system, 1) is based on "GBASE", a general purpose data base, which runs on a UNIX work station, 2) works on a network file system and is connected to PET cameras and other data acquisition devices as well as to an image analysis system "Dr.View", 3) centrally manages the data stored in a data storage unit, 4) is easily modifiable and expandable, and 5) has a human friendly interface which requires minimum operation for registration, retrieval and management.

Characterization of peripheral blood stem cells in mice.

Peripheral blood stem cells (PBSCs) were mobilized in mice by treatment with cytosine-arabinoside on day 0, followed by the administration by injection of granulocyte colony-stimulating factor for 4 days. There were remarkable increases in the numbers of cells with lineage-negative (Lin-) c-kit+ markers, cells with colony-forming unit-cell (CFU-C) and colony-forming unit-spleen (CFU-S) activities, and cells with marrow-repopulating ability (MRA) in the extramedullary sites (the spleen, peripheral blood, and liver) on day 5, whereas the number of these immature hematopoietic cells decreased in the bone marrow (BM) on day 5. This finding suggests the mobilization of immature hematopoietic cells from the BM to the extramedullary sites.