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51.
Toshiyuki Nagata Kentaro Minami Masatatsu Yamamoto Tsubasa Hiraki Masashi Idogawa Katsumi Fujimoto Shun Kageyama Kazuhiro Tabata Kohichi Kawahara Kazuhiro Ueda Ryuji Ikeda Yukio Kato Masaaki Komatsu Akihide Tanimoto Tatsuhiko Furukawa Masami Sato 《International journal of molecular sciences》2021,22(21)
52.
Jun Ogata Kentaro Hirao Kenya Nishioka Arisa Hayashida Yuanzhe Li Hiroyo Yoshino Soichiro Shimizu Nobutaka Hattori Yuzuru Imai 《International journal of molecular sciences》2021,22(7)
Leucine-rich repeat kinase 2 (LRRK2) is a major causative gene of late-onset familial Parkinson’s disease (PD). The suppression of kinase activity is believed to confer neuroprotection, as most pathogenic variants of LRRK2 associated with PD exhibit increased kinase activity. We herein report a novel LRRK2 variant—p.G2294R—located in the WD40 domain, detected through targeted gene-panel screening in a patient with familial PD. The proband showed late-onset Parkinsonism with dysautonomia and a good response to levodopa, without cognitive decline or psychosis. Cultured cell experiments revealed that p.G2294R is highly destabilized at the protein level. The LRRK2 p.G2294R protein expression was upregulated in the patient’s peripheral blood lymphocytes. However, macrophages differentiated from the same peripheral blood showed decreased LRRK2 protein levels. Moreover, our experiment indicated reduced phagocytic activity in the pathogenic yeasts and α-synuclein fibrils. This PD case presents an example wherein the decrease in LRRK2 activity did not act in a neuroprotective manner. Further investigations are needed in order to elucidate the relationship between LRRK2 expression in the central nervous system and the pathogenesis caused by altered LRRK2 activity. 相似文献
53.
Myo Than Htay Yuji Tani Yoshio Hashimoto Kentaro Ito 《Journal of Materials Science: Materials in Electronics》2009,20(Z1):341-345
ZnO nanowires were grown by an ultrasonic spray pyrolysis technique. The aspect ratio and size of the wire were dependent
mainly on the pH value of a precursor solution and the growth temperature. By high-resolution transmission electron microscopic
analysis and photoluminescence measurements, it was confirmed that the nanowires are monocrystalline with good optical quality. 相似文献
54.
Masayuki Ohta Keitaro Kondo Masayuki Matsunaka Hiroyuki Miyamaru Isao Murata Toshiyuki Iida Kentaro Ochiai Chikara Konno 《Fusion Engineering and Design》2009,84(7-11):1446-1449
Integral benchmark experiments with DT neutrons are not always sufficient for nuclear data benchmarking in the MeV region, below 10 MeV. A neutron spectrum shifter, which will be placed between a sample and a DT neutron source, is effective to moderate DT neutrons incident to the sample. In order to estimate effects of the spectrum shifter, the ratio of the contribution of 14 MeV neutrons in the leakage neutron and gamma-ray spectra was calculated with MCNP-4C for an experimental configuration at FNS of JAEA, Japan. The calculations were carried out for a Li2TiO3 sample with a Be, D2O, or 7LiD spectrum shifter. It was found out that the Be shifter was superior to others and the Be shifter was effective to decrease the contribution of 14 MeV neutrons especially for secondary gamma-ray spectrum measurements. 相似文献
55.
Shinobu Hashimoto Kentaro Hattori Ayuka Nakahashi Yuji Iwamoto 《Materials Research Bulletin》2009,44(1):70-3888
Pure-phase LiAl5O8 was selected as an oxide ceramic red phosphor material without dopants (color centers) and was synthesized using a self-flux method. The LiAl5O8 was formed by heating a powder mixture consisting of γ-Al2O3:Li2SO4 = 1:2 (molar ratio) at over 1100 °C for 1 h. Photoluminescence (PL) properties for the synthesized LiAl5O8 were investigated. The maximum intensity of the excitation spectrum for the photoluminescent emission of LiAl5O8 synthesized was at 274 nm. The peak intensity of the emission spectrum was at a wavelength of 667 nm (red color). The intensity of the peak emission spectrum increased with the heating temperature, i.e., the maximum peak intensity of the red emission spectrum was detected for the LiAl5O8 synthesized by heating at 1500 °C for 1 h. 相似文献
56.
Shioiri S Ito S Sakurai K Yaguchi H 《Journal of the Optical Society of America. A, Optics, image science, and vision》2002,19(11):2169-2179
We measured the lowest velocity (velocity threshold) for discriminating motion direction in relative and uniform motion stimuli, varying the contrast and the spatial frequency of the stimulus gratings. The results showed significant differences in the effects of contrast and spatial frequency on the threshold, as well as on the absolute threshold level between the two motion conditions, except when the contrast was 1% or lower. Little effect of spatial frequency was found for uniform motion, whereas a bandpass property with a peak at approximately 5 cycles per degree was found for relative motion. It was also found that contrast had little effect on uniform motion, whereas the threshold decreased with increases in contrast up to 85% for relative motion. These differences cannot be attributed to possible differences in eye movements between the relative and the uniform motion conditions, because the spatial-frequency characteristics differed in the two conditions even when the presentation duration was short enough to prevent eye movements. The differences also cannot be attributed to detecting positional changes, because the velocity threshold was not determined by the total distance of the stimulus movements. These results suggest that there are two different motion pathways: one that specializes in relative motion and one that specializes in uniform or global motion. A simulation showed that the difference in the response functions of the two possible pathways accounts for the differences in the spatial-frequency and contrast dependency of the velocity threshold. 相似文献
57.
Safwat Hassaballa Yasushi Sonoda Kentaro Tomita Young Kee Kim Kiichiro Uchino 《Journal of the Society for Information Display》2005,13(8):639-645
Abstract— Properties of a plasma‐display‐panel (PDP) like discharge were examined by emission and laser Thomson scattering (LTS) measurements. Emission measurements were performed using an intensified CCD camera. By varying several external parameters such as the amplitude of the input voltage, gas composition, and pressure, the influence of these parameters on the discharge behavior was studied. Results of emission measurements showed that they were in good agreement with similar emission measurements on real PDP cells. LTS measurements were performed for the striated PDP‐like discharge at a pressure of 100 Torr and the results showed clear modulations in both profiles of electron density and electron temperature. 相似文献
58.
N. L. Weinberg G. M. Blank H. A. Aulich A. Kentaro Hoffmann T. B. Reddy 《Journal of Applied Electrochemistry》1973,3(3):227-230
An electrochemical method has been developed for bonding electrically-conductive adherends. The procedure is based on the electrochemical generation of a curing agent from an otherwise chemically-unreactive precursor mixed with an epoxy resin sandwiched between the bonding members. The one-part epoxy resin is storage stable and cured rapidly on passage of current. 相似文献
59.
Friend J Nakamura K Ueha S 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2004,51(7):871-878
A torsional microtransducer for high-power applications was developed using standard bulk lead zirconium titantate (PZT) placed upon a small rectangular prism made from phosphor bronze, with a tapered conical end serving as a horn and a machined interior to improve the actuator's response. Torsion was obtained from a prototype at the design frequency of 192 kHz as well as over a wide range of frequencies from 136 kHz to 1.02 MHz. Torsional vibration velocities of 335 mm/s at 192 kHz were measured at 27.3 V(RMS) on the 1.5-mm diameter output tip, amounting to 25,600 degree/s vibration velocity along the outer circumference of the tip. At 1.02 MHz, a torsional vibration velocity of 1750 mm/s (134,000 degree/s) at 17.8 V(RMS) was obtained through use of the thickness mode of the PZT elements. Using the design described in this study, high-power torsional transducers with diameters of 5 mm and below are now possible. 相似文献
60.