46 research outputs found
Oculomotor Nerve Palsy following Cardiac Tamponade with Churg-Strauss Syndrome: A Case Report
A 57-year-old man with a history of more than 10 years of bronchial asthma and chronic sinusitis complained of double vision which developed 18 days after cardiac tamponade with eosinophil-rich fluid (eosinophils 30%). He had oculomotor nerve palsy, and a blood test revealed eosinophilia (12,700/mm3) and elevation of both C-reactive protein and rheumatoid factor. He was diagnosed as having Churg-Strauss syndrome. His symptoms were relieved by corticosteroid therapy. Our case and previous cases in the literature revealed that oculomotor nerve palsy in Churg-Strauss syndrome is associated with pupil involvement and may be relieved by corticosteroid treatment
Vertical oxide semiconductor field-effect transistor with extremely low off-state current
Oxide semiconductor field-effect transistors (OSFETs) are actively developed for display applications. An OSFET exhibits a lower off-state current than a silicon FET and enables low-frequency driving. We developed the measurement method and revealed the OSFET exhibits an extremely low off-state current [1]. In addition, we discovered a c-axis aligned crystalline indium-gallium-zinc oxide (CAAC-IGZO) which was unique crystal morphology [2]. A display with a backplane formed using CAAC-IGZO FETs achieves low power consumption owing to idling-stop driving that allows an extremely low refresh rate [3].
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Embedded DRAM using c-axis-aligned crystalline In-Ga-Zn oxide FET with 1.8V-power-supply voltage
An embedded memory using c-axis aligned crystalline In-Ga-Zn oxide (CAAC-IGZO) FETs with an extremely low off-state current on the order of yoctoamperes (yA) (yocto- is a metric prefix denoting a factor of 10-24) is known as a potential next-generation memory [1][2]. A dynamic oxide semiconductor RAM (DOSRAM), where each memory cell is composed of one CAAC-IGZO FET and one capacitor, enables long data retention and long interval of refresh operations with an advantage of extremely low off-state current of the CAAC-IGZO FET. However, negative backgate voltage (Vbg) and word-line driving voltages of 0/3.3 V (VSSL/VDDH) had been required for an access transistor of the memory cell to satisfy high on-state current and low off-state current.
This work shows that DOSRAM operates with 1.8 V-power supply voltage by using a novel driving method.
Figure 1 shows Vg-Id performance of a CAAC-IGZO FET used as a cell transistor. The threshold voltage (Vth) of the CAAC-IGZO FET is controlled by changing a level of Vbg, whereas Vth of the Si FET is controlled by channel doping. Figure 2 shows a block diagram of a prototyped DOSRAM. The refresh rate in DOSRAM mainly depends on the leakage current of cell transistors. To reduce the refresh rate to once an hour, the off-state current of the cell transistors on a non-selected word line needs to be reduced to 200 zeptoamperes (zA) per FET (zepto- is a metric prefix denoting a factor of 10-21) or lower at 85C. The required Vbg is -7.0 V to achieve such an off-state current at Vg 0 V, for example. To obtain approx. 100 MHz-driving frequency, the required on-state current is at least several microamperes. The voltage level difference in the word line, VDDH VSSL, is a factor that determines the on-state current, and in this work is fixed to 3.3 V so that the combination of Vbg and the word line voltage is optimized. The application of negative voltage to the word line enables the leakage current of the cell transistor to be maintained low even when Vbg is increased. For example, whereas the existing driving method meets the above off-state current value with Vbg -7.0 V and the VSSL 0 V, the novel driving method meets the value with Vbg 0 V and VSSL -1.5 V. In the novel driving method, VDDH 1.8 V. There has been a report of a reduction in leakage current of a memory cell by application of negative voltage to a top gate in DRAM using Si CMOS [3]. In contrast to it, DOSRAM including CAAC-IGZO FETs with L 60 nm has a leakage current of 200 zA or lower, which is 7-digit lower than that of the DRAM using Si CMOS, and enables longer data retention.
The evaluation results of the prototyped DOSRAM verify that a reduction in power-supply voltage from 3.3 V to 1.8 V is possible in terms of operation and data retention. This suggests a highly compatible and efficient configuration of an embedded DRAM and a logic circuit where signals can be transmitted with low VDD.
References
[1] S. H. Wu, et al., IEEE Symp. VLSI Tech., pp. 166-167, 2017.
[2] T. Ishizu, et al., IEEE Symp. VLSI Cir., pp. 162-163, 2017.
[3] F. Hamzaoglu et al., IEEE Journal of Solid-State Circuits, vol. 50, no. 1, pp. 150-157, Jan. 2015
Cross sections for nuclide production in proton- and deuteron-induced reactions on 93
Isotopic production cross sections were measured for proton- and deuteron-induced reactions on 93Nb by means of the inverse kinematics method at RIKEN Radioactive Isotope Beam Factory. The measured production cross sections of residual nuclei in the reaction 93Nb + p at 113 MeV/u were compared with previous data measured by the conventional activation method in the proton energy range between 46 and 249 MeV. The present inverse kinematics data of four reaction products (90Mo, 90Nb, 88Y, and 86Y) were in good agreement with the data of activation measurement. Also, the model calculations with PHITS describing the intra-nuclear cascade and evaporation processes generally well reproduced the measured isotopic production cross sections
Topology Optimization of Synchronous Reluctance Motor Using Normalized Gaussian Network
This paper presents the topology optimization of a synchronous reluctance motor using the normalized Gaussian network. In the optimization, the average torque and iron loss are considered. In the resultant motor, the area of the rotor surface adjacent to the stator is found to be reduced when the weight for the iron loss is sufficiently large. On the other hand, large flux barriers are present in the rotor when the average torque is maximized without considering the iron loss
Genetic variation among Japanese populations of chum salmon inferred from the nucleotide sequences of the mitochondrial DNA control region
We examined the nucleotide sequences of 500 bp variable portion from the 5' end of mitochondrial (mt) DNA control region in about 500 individuals from 12 populations that were captured in 11 rivers, six in Hokkaido and five in Honshu, Japan. Comparison of the sequences showed 10 variable sites, defining a total of 12 haplotypes in the examined individuals. All the 12 haplotypes occurred in seven Hokkaido populations, whereas only six haplotypes were found in the five Honshu populations. Among these haplotypes, two were common in all the Hokkaido and Honshu populations. The AMOVA analysis inferred a genetic differentiation among three geographic regions, i.e. Hokkaido, Pacific Ocean coast in Honshu, and Japan Sea coast in Honshu. Haplotype diversity was higher in the populations of Hokkaido than those of Honshu, indicating a greater genetic variation in the Hokkaido than the Honshu populations. The estimates of painwise population F_[ST] suggested that the regional differentiation was mostly ascribed to the divergence between populations in Hokkaido and the Pacific coast in Honshu
Characterization of TetR-type Repressor Which Cause the Delayed Contact-dependent RED Production in Streptomyces coelicolor
Actinomycetes, filamentous Gram-positive bacteria, are a major source of bioactive natural products which can be drug candidates. We have studied about the bacterial interaction induced production of secondary metabolites by actinomycetes. Tsukamurella pulmonis TP-B0596 (Tp) had been shown to possess ability to induce production of secondary metabolites by Streptomyces species, which are not detected or poorly produced in a mono-culture. Until now, 7 classes, total 29 new compounds had been isolated from the co-culture with various actinomycetes and Tp. Object of this study is to elucidate the gene(s) which are involved in the response for activation of secondary metabolism within actinomycetes. Elucidation of the mechanism can lead to the fundamental understanding of bacterial interaction and secondary metabolism, as well as application for genetic tools to discover novel bioactive natural products from untapped gene matters. Here we employed forward-genetic study using mutagenesis by heavy ion beam to investigated the gene(s) responsible for the responsive production of secondary metabolism induced by Tp. Through this screening, 118 mutants from around 152,000 tested spores were obtained. We further tested the phenotype of the 118 mutants by growth on minimum medium and formation of aerial mycelia, and finally selected 59 mutants. We then re-sequenced the genome of 26 mutants and further gene complementation study revealed that molybdopterin biosynthetic enzyme (moeA), and tetR-like transcriptional regulator are also responsible for the phenotype differences. We speculate that the TetR-like protein is a repressor for the expression of adjacent ABC transporter, thus efflux of the unknown small molecule is prevented and accumulated in the cell, which caused stress to cell that can lead to the undecylprodigiosin production