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22.
Tomohito Hamazaki Shigeki Sawazaki Tetsuro Nagasawa Yoko Nagao Yuko Kanagawa Kazunaga Yazawa 《Lipids》1999,34(1):S33-S37
The purpose of the present research was to clarify the effect of docosahexaenoic acid (DHA) intake on behavior and plasma catecholamines (CA). In Study 1, 42 students took either DHA-rich oil capsules containing 1.5–1.8 g DHA/d or control oil capsules containing 97% soybean oil plus 3% of another fish oil for 3 mon in a double-blind fashion. They took a psychological test (PF Study) at the start and end of the study. This study started at the end of summer vacation and ended just before the final exams. In the control group, external aggression (aggression against others) in PF Study was significantly increased at the end of the study as compared with that measured at the start (+8.9%), whereas it was not significantly changed in the DHA group (?1.0%). In a similar double-blind study (Study 2), we measured external aggression under nonstressful conditions. External aggression slightly decreased in the control group, whereas there were no significant changes in the DHA group. In Study 3 with 14 students, plasma CA were measured at the start and end of capsule administration period of 2 mon. Subjects were under continuous stress of the final exams that lasted throughout the whole study period. The ratio of plasma epinephrine to norepinephrine concentrations was significantly increased in the DHA group (78%), whereas it stayed at the same level in the control group. In Study 4, mice were fed either DHA-deficient diet or -sufficient diet for 4 wk, and their rearing frequency (an anxiety index) was measured. In the DHA-sufficient group, the rearing frequency was significantly less than in the other group. These effects of DHA intake may be applied to people in an attempt to ameliorate stress-related diseases. 相似文献
23.
Tubular SiO2 -glass membranes with thin, dense SiO2 layers on porous glass supports were prepared via sputtering, using the novel sputtering apparatus for tubular supports. This apparatus had a holder for tubular supports and a rotation mechanism. The sputtering conditions of the membranes were investigated. A support temperature of 573 K was determined to be the best among the temperatures that were selected in our experiments. Scanning electron microscopy observations showed that the membrane surfaces became smooth as the sputtering time increased and had no cracks. The permeances of helium, nitrogen, and CO2 were measured at a temperature of 373 K. The permeances for the membranes were on the order of 10-9 molm-2 s-1 Pa-1 (10-5 cm3 (STP)cm-2 s-1 (cm Hg)-1 ). The ratio of the permeances of helium to nitrogen was similar to the theoretical Knudsen value. These values were much lower than the values that were expected from the dense SiO2 glass. This phenomenon was considered to be attributable to the presence of microcracks during the sputtering deposition. 相似文献
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In 1996, the authors proposed a novel method to prepare micron-sized, hollow cross-linked polymer particles. This method is based on the self-assembling of phase separated polymer at interface with water, which was named SaPSeP method, formed by suspension polymerization of divinyl monomer in toluene droplet dissolving previously polystyrene. The SaPSeP method was developed to be applicable to polyaddition reaction system of epoxy resin with diamine. The presence of PS dissolving in epoxy/diamine/toluene droplets promotes the phase separation of the epoxy resin reacted with the diamine. The epoxy resin molecules tend to adsorb at the interface of the droplets. These points were accord with the required conditions for the preparation of hollow particle by the SaPSeP method. Cured epoxy resin particles having one hollow were successfully prepared by the polyaddition reaction in the dispersed system of Epikote 806/630/604, of which equivalent ratio was 5/4/1. 相似文献
26.
T. Kitatani Y. Yazawa S. Watahiki K. Tamura J. Minemura T. Warabisako 《Solar Energy Materials & Solar Cells》1998,50(1-4):221-227
We have developed an optimal growth procedure for gas-source MBE production of a GaInP/GaAs heterointerface. The interface quality is crucial to obtaining high-performance GaAs solar cells with a GaInP barrier layer because minority carrier lifetime depends strongly on the interface structure. In situ Reflective High-Energy Electron Diffraction (RHEED) observation during the growth across the GaInP/GaAs heterointerface revealed that the phosphorus atoms are replaced by arsenic atoms in the near-interface region of the GaInP layer, and a transient layer acting as a carrier trap is formed. Introduction of a GaP layer into the interface was found to be effective in suppressing carrier loss. From Composition Analysis by Thickness Fringe-Transmission Electron Microscopy (CAT-TEM) images, it was also found that the optimum thickness of inserted GaP to avoid the generation of misfit dislocations is 1 nm. 相似文献
27.
Hong Lin Tetsuro Jin riy Dmytruk Tetsuo Yazawa 《Journal of the American Ceramic Society》2003,86(11):1991-1993
A translucent, conductive, porous nanocomposite was designed and prepared by depositing SnO2 on the inner surfaces of the pores of a porous glass plate and on its outer surface using a chemical vapor deposition method. The porous nanocomposite almost maintained its large surface area and pore volume because the pores remained open after they were deposited with SnO2 . Conductivity between the two outer surfaces of the nanocomposite plate was confirmed for the first time. 相似文献
28.
The binding of antibiotics (gentamicin, oleandomycin and chloramphenicol) to vitelline and fertilization envelopes and their extracts was investigated by immunohistochemical and immunocytochemical techniques and immunoblot analysis using mature and artificially activated eggs of the fish Oncorhynchus masou. Binding of antibiotics was detected in the vitelline and fertilization envelope outermost layers, the fertilization envelope inner surface and cortical alveolus exudates, with differences in immunoreactive intensity and deposition. The fertilization envelope outermost layer had the capacity to bind much greater amounts of the antibiotics than the vitelline envelope outermost layer. The greater capacity was caused by the deposition of cortical alveolus exudates, which were known to be responsible for functional roles of protection against bacteria, fungi and noxious materials. Treatment of the vitelline and fertilization envelopes with neuraminidase markedly reduced the binding of gentamicin and chloramphenicol but slightly increased that of oleandomycin; binding of the latter to the vitelline and fertilization envelope outermost layers was considerably reduced after treatment with alpha-fucosidase. Treatment of the two envelopes with alpha-mannosidase, beta-galactosidase or beta-D-glucosaminidase did not cause any alteration in immunoreactive intensity or number of immunoreactive deposits. Immunoblot analysis of the vitelline or fertilization envelope extracts indicated that many of the antibiotic-binding substances were glycoproteins, and several major bands were bound by all three antibiotics. These results suggest that the vitelline or fertilization envelopes may have the ability to protect the egg itself, or the embryo, respectively, by trapping antibiotics, and the trapping may be related to the presence of carbohydrate moieties, such as sialyl or fucosyl residues. 相似文献
29.
T. Uematsu K. Tsutsui Y. Yazawa T. Warabisako I. Araki Y. Eguchi T. Joge 《Solar Energy Materials & Solar Cells》2003,75(3-4):557-566
Bifacial cells have been developed for use in flat-plate static-concentrator modules and bifacial photovoltaic modules. All but one of the fabrication processes are conventional mass production processes, making it possible to produce these cells at low cost. By using 12.5×12.5 cm SOG wafers, bifacial cells with about 15% front- and 10.5% rear-illumination efficiencies have already been developed, and cells achieving higher efficiencies for both surfaces are being developed now. By applying these cells, a bifacial-cell-type flat-plate static-concentrator module showed 82% optical-collection efficiency for normal-incident light with a 2.0 concentration ratio. We have also applied bifacial cells for non-concentrating bifacial modules and developed a new application that reduces the limitations on PV module installation. 相似文献
30.
Y. Yazawa J. Minemura K. Tamura S. Watahiki T. Kitatam T. Warabisako 《Solar Energy Materials & Solar Cells》1998,50(1-4):163-168
We report on process damage free thin-film GaAs cells detached from the GaAs substrates. GaAs cells grown by gas-source MBE were thinned by the epitaxial liftoff (ELO) technique. Photoluminescence spectroscopy showed a peak splitting in the band emission, indicating that a strain was induced in the thin-film cell fixed on the quartz glass substrate. The strain, however, was found not to affect the quality of the thin-film cells, based on the fact that the peak intensity was almost twice that before ELO. The thin-film GaAs cells showed no evidence of degradation in diode characteristics and spectral responses. The keys to avoiding damage on the active region of the solar cell during the thinning process are the introducing a GaInP window layer and improving the thin film process including metallization on thin film cells. These results demonstrates that the thinning and transfer processes dol-not affect the quality of the active region of the cells. 相似文献