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81.
Dementia of frontal type (DFT) is a fairly common degenerative disease distinct from Alzheimer's disease (AD), whose reportedly distinctive instrumental feature is frontal lobe hypoperfusion on SPECT. We evaluated the cortical dopaminergic system in 6 AD, 5 DFT, and 6 control subjects with SPECT and both [99Tc]-HM-PAO, a perfusion tracer, and [123I]-IBZM, a D2 postsynaptic ligand. Both in AD and DFT patients, [99Tc]-HM-PAO SPECT showed a relative frontal hypoperfusion. On the contrary, [123I]-IBZM SPECT showed significantly reduced ligand uptake in superior frontal regions of DFT (0.89 +/- 0.08 relative to control subjects) as compared to AD patients (0.97 +/- 0.02; difference of means: 0.08, 95% Confidence Interval 0.004 to 0.156; p = 0.041). Results suggest more marked involvement of the frontal cortical dopaminergic system in DFT than in AD patients. 相似文献
82.
OBJECTIVE: The study was designed for the analysis on data of 51 patients with macular branch retinal vein occlusion (McBRVO) and the comparison between them and 210 patients (214 eyes) with major branch retinal vein occlusion (MjBRVO). METHODS: Fluorescein angiography, ophthalmoscope and slit-lamp were used for the examination of the venous obstructive site and the locations of artery and vein. RESULTS: (1) The incidence of McBRVO was 19.5% (51/261) in branch retinal vein occlusion. (2) The site of occlusion: the incidence of McBRVO at supero-temporal branches was 72.5% (37/51) and the incidence of MjBRVO was 73.4% (157/214). (3) The involved branch at the first macular branch accounted for 39.6%, the second branch 58.3%, and the third branch 2.1%. The artery anterior to the vein at arteriovenous crossing at the obstructive site accounted for 93.0% in the McBRVO group and 95.0% in the MjBRVO group. (4) The complications and visual prognosis: The incidence of cystoid macular edema was 20.0% in McBRVO group and that was 28.5% in the MjBRVO group. No neovascularization was found in the McBRVO group, while 37.9% neovascular formation was found in the MjBRVO group. The visual acuity recovered to 0.5 or better was in 88.2% in the McBRVO group, while 57.0% in the MjBRVO group (P < 0.005). CONCLUSION: There are no significant differences in sex, age, laterality, pathogenesis as well as occlusion site between the McBRVO and MjBRVO groups, but the visual prognosis is better in the former than that in the latter group. 相似文献
83.
In controller design of dynamical systems, it is desirable that the controllers guarantee the stability for not only nominal plants but also perturbed ones, because the plant models may have some uncertainties in their parameters. By this motivation, several studies for the robust controller design have been conducted. In this paper, a feedback controller design method is considered, which achieves enlarging the degree of robust stability for the linear SISO closed‐loop systems. Choosing stability radius for the plant parameters as the degree of robust stability, and regarding this as an object function, we formulated this maximization as an optimization problem with constraints coming from prescribed pole placement. The difficulty of this formulation is that while pole placements give linear constraints, the object function is not a smooth one, which calls for an optimization technique for nondifferentiable functions. To cope with this, we successfully used the bundle method. We show some numerical examples to illustrate our proposed design method. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(3): 55–61, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20623 相似文献
84.
Masato Sakurai Rodney L. Heckaman Stacey E. Casella Mark D. Fairchild Takehiro Nakatsue Yoshihide Shimpuku 《Journal of the Society for Information Display》2008,16(12):1203-1211
Abstract— The effect of varying the color gamut of an extended‐gamut LCD on color appearance and preference was measured psychometrically in two experiments at each of two separate laboratories over a representative set of 10 images each. The first experiment measured the effect of color gamut on appearance, and the effect on the appearance attribute colorfulness was shown to be relatively strong compared with other attributes as the volume of display color gamut is varied. Overall, colorfulness monotonically increased at constant sensitivity as the gamut area in xy chromaticities increased while tending to become less and less sensitive to increasing the gamut volumes in CIELAB and CIECAM02. In the second experiment, the overall preference indicated an optimal color gamut for the display gamut volume even though the results were shown to be highly scene dependent. 相似文献
85.
Jun-ichi Kadokawa Yoshifumi Nakamura Yousuke Sasaki Yoshiro Kaneko Takehiro Nishikawa 《Polymer Bulletin》2008,60(1):57-68
Summary This paper reports chemoenzymatic synthesis of amylose-grafted polyacetylenes according to the following reaction manners.
Polymerization of a N-propargylamide monomer having a maltooligosacchairde chain was firstly carried out using a water-soluble Rh-catalyst in water,
giving maltooligosaccharide-grafted polyacetylene. The 1H NMR spectrum of the product supported the structure of the desired polyacetylene. Then, the enzymatic chain-elongation from
the oligosaccharides of the polymer was performed using glucose-1-phosphate catalyzed by phosphorylase to give the polyacetylene
having amylose side-chains. Furthermore, copolymerization of the monomer with the other N-propargylamide monomer was performed under the conditions similar to those of homopolymerization. The phosphorylase-catalyzed
enzymatic chain-elongation of the copolymer was also carried out. The DLS measurement of the amylose-grafted polyacetylenes
in alkaline solution was conducted. 相似文献
86.
Junko Yotani Sashiro Uemura Takeshi Nagasako Hiroyuki Kurachi Takehiro Nakao Masaaki Ito Akira Sakurai Hideo Shimoda Tomotaka Ezaki Kazuhiko Fukuda Yahachi Saito 《Journal of the Society for Information Display》2009,17(4):361-367
Abstract— A high‐luminance 1.8‐mm‐pixel‐pitch CNT‐FED for color character displays has been developed. The display panel has 32 × 256 color pixels, and the subpixel size is 0.6 × 1.8 mm. The display panel can provide good visibility when installed even in outdoor locations. The power consumption is low enough for the display to be battery driven. The practical application is the display of important messages regarding the evacuation from disaster areas, even under emergent no‐power conditions similar to the messages on vending machines. 相似文献
87.
Hiroshi Tamura Takehiro Konoike Yukio Sakabe Kikuo Wakino 《Journal of the American Ceramic Society》1984,67(4):c59-c61
Microwave characteristics of the system Ba(Zn1/3 Ta2/3 )O3 -BaZrO3 were investigated. Ba(Zn,Ta)O3 has a perovskite pseudocell and hexagonal superstructure; the superstructure was not formed after addition of BaZrO3 . Both sintering and crystallization of Ba(Zn,Ta)O3 -BaZrO3 were accelerated compared to those of Ba(Zn,Ta)O3 alone, and the microwave Q value was also improved. The material optimized for the dielectric resonator, Ba(Ni,Ta)O3 -Ba(Zr,Zn,Ta)O3 , has a dielectric constant of 30, Q value of 10000 at 10 GHz, and temperature coeficient of resonant frequency of 0 ppm/°C. 相似文献
88.
Distribution of storage proteins in low-glutelin rice seed determined using a fluorescent antibody 总被引:4,自引:0,他引:4
Furukawa S Mizuma T Kiyokawa Y Masumura T Tanaka K Wakai Y 《Journal of Bioscience and Bioengineering》2003,96(5):467-473
To compare the distribution of storage proteins in low-glutelin rice seed with that in other cultivars having normal protein compositions, immunofluorescence labeling with specific antibodies was applied to visualize the distribution of storage proteins in endosperm tissues. The endosperm tissues from five cultivars were reacted with anti-prolamin and anti-glutelin antibodies, and then observed by light microscopy and confocal laser scanning microscopy (CLSM). In low-glutelin rice, using microscopic analysis, a large proportion of storage proteins was observed in the endosperm tissue of 70% polished rice. To determine the localization of two types of protein bodies in endosperm tissues, images of the distribution of the type I protein body (PB-I) and the type II protein body (PB-II) were obtained by CLSM. The CLSM images showed that, in low-glutelin rice, prolamin which accumulates in PB-I remains in the center of 70% polished rice grains despite the elimination of 30% of the outer layer of brown rice grains. However, the other cultivars mostly contained glutelin which accumulates in PB-II and is distributed throughout the endosperm tissues. This shows that low-glutelin rice differs from the other cultivars not only in the major storage protein composition but also in the distribution of storage proteins in endosperm tissues. 相似文献
89.
90.
Kiyotaka Tsunemi Kikuo Yoshida Madoka Yoshida Etsuko Kato Akemi Kawamoto Takehiro Kihara Tei Saburi 《International Journal of Hydrogen Energy》2017,42(41):26175-26182
Organic hydride hydrogen refueling stations are currently being developed in Japan. For these stations, we estimate the consequence and damage caused by explosions and heat radiation after a hydrogen leak, and the acute toxicity caused by the leakage and dispersion of methylcyclohexane and toluene energy carriers. First, the organic hydride hydrogen refueling station is defined, and an accident scenario for four leak sizes of hydrogen and chemical leak accidents is set. Next, simulations of the blast wave pressure and heat radiation after the hydrogen leak and of atmospheric dispersion for the evaporation after liquid methylcyclohexane and toluene leaks are performed. Probit functions or threshold values are created for each type of effects caused by the explosion, heat and the inhalation effect on humans of toluene acute toxicity. Population data for the area surrounding the station are created in a 10-m mesh. The consequence and damage are estimated for each leak size. The results show that although the explosion and chemical leak affects the area around the refueling station, the effects are small in all of the accident scenarios. In contrast, although the area of the heat effect is limited to inside the refueling station, the burn damage is large, and there is a need for conducting quantitative risk assessment. 相似文献