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451.
Midori Shimizu Hitoshi Tainaka Taro Oba Keisuke Mizuo Masakazu Umezawa Ken Takeda 《Particle and fibre toxicology》2009,6(1):20
Background
Nanotechnology is developing rapidly throughout the world and the production of novel man-made nanoparticles is increasing, it is therefore of concern that nanomaterials have the potential to affect human health. The purpose of this study was to investigate the effects of maternal exposure to nano-sized anatase titanium dioxide (TiO2) on gene expression in the brain during the developmental period using cDNA microarray analysis combined with Gene Ontology (GO) and Medical Subject Headings (MeSH) terms information. 相似文献452.
The Authors report their experience in the treatment of twenty-one patients with intussusception operated in the Paediatric Surgery Division ASL FG/3 between January 1988 and December 1994. Eighty-nine percent of the patients were between 2 and 12 months of age, with a peak between 2 and 6 months (60%). Ultrasound allowed to identify the pathological picture in forty-two percent of the cases and diagnosis was confirmed by barium enema. In 8 patients a pathology more or less responsible of the intussusception or associated with it was detected. The time between the onset of symptoms and admission as well as the relation between intestinal resection and duration of symptomatology were analyzed. The resection rate was maximal (55%) in those patients presenting symptoms beyond 25 hours. Intestinal resection was performed in 9 patients (47%): 6 ileo-colic; 1 ileo-colic resection extended to the splenic flexure; and 2 ileo-ileal ones. In this series no postoperative complications or recurrences or deaths were registered. Long term results proved that ileo-colic resection, even in few-months old infants, is well tolerated. 相似文献
453.
Synopsis The effect of vanadium, in the range 5 to 1000 ppm, on the microstructure and properties of manual metal arc welds containing 0.6 to 1.8 % Mn has been investigated. It was found that vanadium increased the acicularity of as‐deposited metal and modified the grain size and the microphases in reheated regions. The hardness of the weldments increased and the tensile properties were defined by equations of the form: σ =a+b.Mn+c.V‐d.V2 In the as‐welded condition vanadium was found, in some instances, to be marginally beneficial for notch toughness whereas after stress‐relieving the element had a progressively deleterious effect at all manganese levels. On balance, it is concluded, for the associated titanium content, that up to 200 ppm V can be tolerated without undue concern. 相似文献
454.
Keito Boki Sanji Shinoda Mayumi Abe Seiko Shimizu 《Journal of the American Oil Chemists' Society》1990,67(6):373-375
Effects of filtration bleaching on thiobarbituric acid values (TAV) and carbonyl values (CV) of autoxidized soybean oil were
investigated by using sixteen kinds of bleaching media in order to improve oil quality. The standard activated clay was the
most effective in reducing the amounts of aldehydes and ketones in autoxidized soybean oil. From the decreases in TVA and
CV and physical and chemical properties of media, it was concluded that decreases of TAV and CV are mainly dominated by the
acidity over the highest range, +1.5∼−5.6, rather than the acidity over the lower acid strength ranges, total acidity or specific
surface area of media. From the results of chemical composition and acidity over the highest range (+1.5∼−5.6) of the clays
and TAV or CV reduction by using the heattreated clays, it was suggested that the acidity over the highest range originated
from the water contained between layers and bound water in the clay. 相似文献
455.
Taro Naoi Hai Lin Atsushi Hirota Eishiro Otani Kimio Amemiya 《Journal of the Society for Information Display》2009,17(2):113-119
Abstract— Pioneer Corporation introduced plasma‐display‐panel (PDP) TVs in 2005, which achieved the highest dark‐room contrast ratio of 4000:1 at the time. These PDPs had a novel discharge cell structure consisting of a crystal emissive layer (CEL) on a MgO protective thin film. This cell structure is refered to as a CEL structure. Magnesium‐oxide single‐crystal particles, which have a unique luminance peak around 230–250 nm and a good exo‐electron‐emission property, were found to be an excellent material for CEL and were utilized in CEL panels. In 2007, newly developed PDP TVs in which CEL was formed on a phosphor layer, in addition to the previous CEL structure, were introduced, and this discharge cell structure is refered to as advanced CEL structure. By using the new cell structure, the opposed discharge characteristics have been drastically improved, and a stable reset discharge has been realized with only a weak opposed discharge. As a result, black luminance has been drastically reduced, and a dark‐room contrast ratio of over 20,000:1, the highest ever reported, has been achieved. 相似文献
456.
Toshiyuki Akiyama Takashi Yamada Masatoshi Kitagawa Tsutae Shinoda 《Journal of the Society for Information Display》2009,17(2):121-130
Abstract— The discharge mechanism concerning the width of the display electrodes in high‐Xe‐content gas mixtures to improve the luminous efficacy of PDPs has been researched. It was found that a luminous efficacy of 5 lm/W was realized for a high‐Xe‐content gas mixture and narrower display electrodes. For a high‐Xe‐content gas mixture, the luminous efficacy increases as the display electrode becomes narrower. This phenomenon was analyzed by observing the emission from a discharge cell. The observation data indicate that a high electron heating efficiency contributes to increased luminous efficacy along with narrow electrodes for a high‐Xe‐content gas mixture as well as high excitation efficiency. 相似文献
457.
458.
U. Madeleno H. Liu T. Shinoda Y. Mishima T. Suzuki 《Journal of Materials Science》1990,25(7):3273-3280
An investigation is carried out on the interfacial wetting behaviour and reactions between aluminium and alumina fibres (85mass% Al2O3 and 15mass% SiO2). Aluminium is coated onto alumina fibres by a vacuum evaporation technique and the surface of the fully coated fibres and the edge of the partially coated fibres are examined by scanning electron microscope after heat treatments at various temperatures. Within a temperature regime between 943 and 1273 K, occurrence of such interfacial reactions as 4Al(I) + Al2O3(s) 3Al2O3(g) and 4Al(I) + 3SiO2(s) 2Al2O3(s) + 3Si(s) are detected. It is found that molten aluminium can cover the alumina fibre surface but it peels off near the edge of the coating film on a partially coated fibre, showing the very weak interface cohesion. This is ascribed to the lack of a stable compound formation at the interface. Results of tensile test show that the strength of the coated fibres is degraded after heat-treating at above the melting point of aluminium. The culprits for the tensile failure of alumina fibres are evaluated by the Weibull distribution theory. 相似文献
459.
Toshihiro Akihisa Yoshihiko Inada Parthasarathi Ghosh Swapnadip Thakur Fumiko U. Rosenstein Toshitake Tamura Taro Matsumoto 《Journal of the American Oil Chemists' Society》1988,65(4):607-610
Compositions of the triterpene alcohol fractions of the unsaponifiable lipids obtained from 28 seed and mature plant [aerial
parts (leaves and stems), pericarp of the fruits, and roots] of 13 genera of the family Cucurbitaceae were determined by gas
liquid chromatography (GLC) on an OV-17 glass capillary column. Among the 14 tetracyclic and pentacyclic triterpene alcohols
identified, isomultiflorenol was found to be the major component for most of the seed materials. The abundance of this triterpene
suggests that it may be a taxonomical marker of the seeds of Cucurbitaceae since only a few higher plants are known to contain
isomultiflorenol. The mature plant materials of the Cucurbitaceae, on the other hand, were shown to contain either one or
some of the common triterpene alcohols such asα- andβ-amyrins, cycloartenol and 24-methylenecycloartanol as the major triterpene constituents. 相似文献
460.
Taro Ura 《Theory of Computing Systems》1975,9(2):159-189
O. Hájek proved in his book Dynamical Systems in the Plane (Chapter III) that there isat most one abstract local dynamical system which is locally equivalent to, or equivalently an extension of, a given elementary dynamical system, and suggested a question of finding reasonable conditions on the latter for the existence ofat least one such abstract local dynamical system. An elementary dynamical system is said to satisfy the No-Intersection Axiom and is called an abstract germ if(x
1, t) = (x
2,t) impliesx
1 =x
2. We show that is (uniquely) extendable to an abstract local dynamical system if and only if is an abstract germ, and hence the question is completely answered. After introducing various kinds of isomorphisms of abstract germs and abstract local dynamical systems corresponding to those of continuous germs and continuous local dynamical systems, we obtain some sufficient conditions for extendability of isomorphisms and possibility of restriction of them, and thus establish the local determinacy of abstract local dynamical systems up to isomorphisms in some wider categories.Dedicated to Professor Yusuke HAGIHARA in Commemoration of His Seventy-Seventh Anniversary 相似文献