Orbital Liquid in Perovskite Transition-Metal Oxides

We study the effects of the degeneracy of the $e_g$ orbitals as well as the double exchange interaction with $t_{2g}$ spins in perovskite transition-metal oxides. In addition to the spin field ${\vec S}_i$, the isospin field ${\vec T}_i$ is introduced to describe the orbital degrees of freedom. The isospin is the quantum dynamical variable, and is represented by the boson with a constraint. The dispersion of this boson is flat along $(\pi/a,\pi/a,k_z)$ ($a$: lattice constant) and the other two equivalent directions. This enables the orbital disordered phase down to low temperatures. We interpret some of the anomalous experiments, i.e., optical absorption and d.c. resistivity, in the low temperature ferromagnetic phase of La$_{1-x}$Sr$_x$MnO$_3$ with $x > 0.2$ in terms of this orbital liquid picture.Comment: 4 pages, RevTex and 1 Postscript figur

A New Application of Transient Recorder to Magnetic Measurements (Part I: Core Loss Measurement at Very Low Frequencies)

A new method have been developed based upon analogue-to-digital conversion techniques and memories. The method involves the scaling of operating frequency from "real" to "optimum" for the power loss measurement. The advantages of using this techniques are as follows: (1) extreme availability at lower frequency region, (2) high accuracy and high stability, (3) simple measuring procedure, (4) digital indication. This method can be measured the power losses over the frequency range 0.1Hz to 1kHz for magnetic circuit and d.c. to 1kHz in such a purely resistive circuit. We estimate the accuracy of this core loss measuring system within 1.0% over all these frequency range. Using this system, specific core losses of the various grades of silicon iron have been measured in the frequency range 0.1Hz to 200Hz

Experimental Studies of Various Factors Affecting Minor Loop Hysteresis Loss

When the distorted flux is induced in a magnetic circuit, the minor loops arise sometimes inside the major hysteresis loop. The area, accordingly the hysteresis loss of the minor loop,is affected by its amplitude and position, by the maximum flux density, by the quality of material, etc.. In this paper, we describe the experimental studies of the factors on the minor loop hysteresis loss. A method of getting the displacement factor of a minor loop which is placed at arbitrary position and has any amplitude is developed from our experimental results. Using this method, the core losses caused by the distorted flux can be calcuLated within the error less than three percent, even if the amplitude of the minor loop becomes near to the amplitude of the major loop

A Field-programmable VLSI based on an asynchronous bit-serial architecture

科研費報告書収録論文(課題番号:17300009/研究代表者:亀山充隆/システムインテグレーション理論に基づく高安全知能自動車用VLSIの最適設計

Sh3bp2 Gain-Of-Function Mutation Ameliorates Lupus Phenotypes in B6.MRL-Faslpr Mice

SH3 domain-binding protein 2 (SH3BP2) is an adaptor protein that is predominantly expressed in immune cells, and it regulates intracellular signaling. We had previously reported that a gain-of-function mutation in SH3BP2 exacerbates inflammation and bone loss in murine arthritis models. Here, we explored the involvement of SH3BP2 in a lupus model. Sh3bp2 gain-of-function (P416R knock-in; Sh3bp2KI/+) mice and lupus-prone B6.MRL-Faslpr mice were crossed to yield double-mutant (Sh3bp2KI/+Faslpr/lpr) mice. We monitored survival rates and proteinuria up to 48 weeks of age and assessed renal damage and serum anti-double-stranded DNA antibody levels. Additionally, we analyzed B and T cell subsets in lymphoid tissues by flow cytometry and determined the expression of apoptosis-related molecules in lymph nodes. Sh3bp2 gain-of-function mutation alleviated the poor survival rate, proteinuria, and glomerulosclerosis and significantly reduced serum anti-dsDNA antibody levels in Sh3bp2KI/+Faslpr/lpr mice. Additionally, B220+CD4-CD8- T cell population in lymph nodes was decreased in Sh3bp2KI/+Faslpr/lpr mice, which is possibly associated with the observed increase in cleaved caspase-3 and tumor necrosis factor levels. Sh3bp2 gain-of-function mutation ameliorated clinical and immunological phenotypes in lupus-prone mice. Our findings offer better insight into the unique immunopathological roles of SH3BP2 in autoimmune diseases

Ectopic Calcification as Discernible Manifestation in Neonates with Pseudohypoparathyroidism Type 1a

The diagnosis of pseudohypoparathyroidism type 1a (PHP1a) is challenging, because both the osteodystrophy, such as brachydactyly and round face, and the symptomatic hypocalcemia usually develop beyond infancy. Although ectopic calcification may be an early sign of PHP1a, there are no systematic reviews regarding the time of its appearance. We here report on two PHP1a patients who presented with subcutaneous calcification in neonatal period