Keiichi Takasugi

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We report an individual who developed Alzheimer's disease (AD) due to a novel presenilin-1 mutation (Alanine-->Valine at codon 431). When he first presented, the patient met criteria for mild cognitive impairment but progressed over 16 months to fulfill diagnostic criteria of AD. At his first presentation, he showed widespread metabolic deficits in the(More)
The axial magnetic field was applied to the Ar gas-puff z-pinch for the control of radial dynamics and x-ray emission from the plasma. The K-shell radiations of Ar ions were suppressed and the L-shell radiations were enhanced by the axial field. The suppression of m=0 mode instability was observed by using a framing camera. The characteristic pinch radius(More)
X-ray spectra of Ar gas-puff z-pinch plasma has been measured with a focusing spectrograph with Johansson type quartz crystal. The obtained spectra showed the presence of K-alpha lines of low ionized ions of Fe and Ar. Intensive electron beam with energy not less than 7 keV was detected by x-ray line measurements.
Spatial and spectral characteristics of Ar gas-puff z-pinch plasma were investigated using a convex crystal spectrograph. Radial distribution of He-like Ar line corresponded to hot spots. H-like Ar line was observed in Cu electrode experiment. K<inf>&#x03B1;</inf> lines of metal atoms had a wide distribution, which corresponded to cloud structure of x-ray(More)
Summary form only given. The divergent gas-puff z pinch has been devised for the realization of efficient point radiation source of x-ray. Because of the axial inhomogeneity introduced at the initiation of discharge, the plasma converges to a small region, and the efficient energy input is obtained compared to the conventional system. The experiment was(More)
Ion transmittance measurements with Al foils were carried out in the divergent gas-puff z-pinch experiments. The highest energy values in the positive and negative discharges were almost equal. This result supports that a part of ions can be accelerated by the current-independent mechanism. Hard X-ray pinhole imaging was carried out, as the additional(More)
Summary form only given. The divergent gas-puff z pinch is a non-uniform system in the axial direction. The degree of non-uniformity can be controlled by the angle of gas-puffing. High-energy ions around 1 MeV have been observed in the divergent gas-puff z-pinch experiment. As the ion acceleration has also been observed in the current reversal experiment,(More)
The axial magnetic field was applied to the Ar gas-puff Z-pinch plasma for the control of soft X-ray and EUV emission. The reduction of soft X-ray and increase of EUV emission were again confirmed. EUV spectroscopic measurement was made on the Z-pinch plasma, and Ar IX and Ar X lines were observed. By applying axial magnetic field of 950 G, those lines(More)
Summary form only given. The divergent gas-puff z-pinch has been devised for the realization of an efficient point radiation source of X-rays. Because of the axial inhomogeneity introduced at the initiation of discharge, the plasma converges to a small region, and the efficient energy input is obtained compared to the conventional z pinch.The experiment was(More)
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