检索结果-南通市图书馆

To Gate, or Not to Gate： Regulatory Mechanisms for Intercellular Protein Transport and Virus Movement in Plants

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Molecular Plant 2011年第5期4卷 782-793页

作者： Shoko ueki Vitaly Citovsky Institute of Plant Science and Resources Okayama University 2-20-1 Chuo Kurashiki Okayama 710-0046 Japan Department of Biochemistry and Cell Biology State University of New York Stony Brook NY 11794-5215 USA

Cell-to-cell signal transduction is vital for orchestrating the whole-body physiology of multi-cellular organ- isms, and many endogenous macromolecules, proteins, and nucleic acids function as such transported signals. In plants, many of these molecules are transported through plasmodesmata （Pd）, the cell wall-spanning channel structures that interconnect plant cells. Furthermore, Pd also act as conduits for cell-to-cell movement of most plant viruses that have evolved to pirate these channels to spread the infection. Pd transport is presumed to be highly selective, and only a limited repertoire of molecules is transported through these channels. Recent studies have begun to unravel mechanisms that actively regulate the opening of the Pd channel to allow traffic. This macromolecular transport between cells comprises two consecutive steps： intracellular targeting to Pd and translocation through the channel to the adjacent cell. Here, we review the current knowledge of molecular species that are transported though Pd and the mechanisms that control this traffic. Generally, Pd traffic can occur by passive diffusion through the trans-Pd cytoplasm or through the membrane/lu- men of the trans-Pd ER, or by active transport that includes protein-protein interactions. It is this latter mode of Pd trans- port that is involved in intercellular traffic of most signal molecules and is regulated by distinct and sometimes interdependent mechanisms, which represent the focus of this article.

关键词： Plasmodesmata cell-to-cell transport plant viruses transcription factors

Velocity and Size of Droplets in Dense Region of Diesel Fuel Spray on Transient Needle Opening Condition

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Thermal Science 2005年第2期14卷 181-186页

作者： Hironobu ueki Masahiro ISHIDA Daisaku SAKAGUCHI Nagasaki University 1-14 Bunkyo-machi Nagasaki 852-8521JapanNagasaki University 1-14 Bunkyo-machiNagasaki 852-8521JapanNagasaki University 1-14 Bunkyo-machiNagasaki 852-8521Japan

In order to investigate the effect of transient needle opening on early stage of spray behavior, simultaneous measurements of velocity and size of droplet were conducted by a newly developed laser 2-focus velocimeter (L2F). The micro-scale probe of the L2F was consisted of two foci with a distance of 36μm. The tested nozzle had a single hole with a diameter of 0.2 mm. The measurements of injection pressure, needle lift, and crank angle were synchronized with the spray measurement by the L2F at the position 10 mm downstream from the nozzle exit. It has been clearly shown that the velocity and size of droplet increase with needle valve opening and that the probability density distribution of droplet size can be fitted to the Nukiyama-Tanasawa distribution under the transient needle opening condition.

关键词： droplet disintegration optical characterization laser 2-focus velocimeter.

Measurement of droplet size distribution in core region of high-speed spray by micro-probe L2F

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2008年第1期17卷 90-96页

作者： Daisaku Sakaguchi Oluwo le Amida Hironobu ueki Masahiro Ishida Graduate School of Science and Technology Nagasaki University1-14 Bunkyo-machi Nagasaki 852-8521 JAPAN Faculty of Engineering Nagasaki University Professor

In order to investigate the distribution of droplet sizes in the core region of diesel fuel spray, instantaneous measurement of droplet sizes was conducted by an advanced laser 2-focus velocimeter （L2F）. The micro-scale probe of the L2F is made up of two foci and the distance between them is 36 lain. The tested nozzle had a 0.2 mm diameter single-hole. The measurements of injection pressure, needle lift, and crank angle were synchronized with the measurement by the L2F at the position 10 mm downstream from the nozzle exit. It is clearly shown that the droplet near the spray axis is larger than that in the off-axis region under the needle full lift condition and that the spatial distribution of droplet sizes varies temporally. It is found that the probability density distribution of droplet sizes in the spray core region can be fitted m the Nukiyama-Tanasawa distribution in most injection periods.

关键词： droplet disintegration optical characterization laser 2-focus velocimeter

Control of Collection Efficiency for Axial Flow Cyclone Dust Collectors with Fixed Guide Vanes and with Funnel Shaped Exit Pipes

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2006年第3期15卷 240-250页

作者： Akira Ogawa masaru Arakawa T-110-0011 Minowa 2-14-7Taitou-KuTokyoJapan SHINWA RULES Co. Ltd.Sanjo-ShiNiigataJapan

The experimental result of the collection efficiency of the axial flow cyclone with the fixed guide vanes is lower than that with the tangential inlet pipe to the cyclone body due to the weak angular momentum transfer given by flowing through the guide vanes. However, one of the interesting points is the control of the collection efficiency depended on the funnel shaped exit pipes. The collection efficiencies for these funnel shaped exit pipes are depended on the Froude number. Then, in this paper, the experimental results of the pressure drop and also the collection efficiency using the fly-ash particles and also the comparison of the calculated results of the collection efficiency with the experimental results are described i~ detail.

关键词： Axial flow cyclone funnel shaped exit pipe fixed guide vanes pressure drop collection efficiency,Froude number cut-Size

Control of Secondary Flow in a Low Solidity Circular Cascade Diffuser

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2012年第4期21卷 384-390页

作者： Daisaku Sakaguchi Takuji Fujii Hironobu ueki Masahiro Ishida Hiroshi Hayami Nagasaki University 1-14 Bunkyo-machi Kyushu University (retired)

According to the previous experimental works on the low solidity circular cascade diffuser (LSD), a pressure recovery of a centrifugal blower was improved by the LSD significantly in a wide range of flow rate, and the pres-sure recovery was improved further by the LSD with a tandem cascade in comparison with the LSD with a sin-gle-row cascade. In the present study, the flow behavior in the LSD with the tandem cascade has been analyzed numerically by using the commercial CFD code of ANSYS-CFX12. It was shown clearly that the higher pressure recovery was achieved by applying the LSD with the tandem cascade, and the high pressure recovery is based on the high pressure rise in the vaneless space upstream of the LSD and the high blade loading of the front blade of the LSD. The high pressure recovery in the LSD could be achieved by controlling the flow separation on the suc-tion surface of the front blade and also on that of the rear blade due to formation of the favorable secondary flow and due to increase in mass flow passing through the slit section between the front and rear blades.

关键词： LSD (Low solidity circular cascade diffuser) Centrifugal blower Range enhancement Tandem cascade

Mechanisms of fertilization elucidated by gene-manipulated animals

在线全文

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2015年第4期17卷 646-652页

作者： masaru Okabe Center for Genetic Analysis for Biological ResponsesResearch Institute for Microbial Diseases OsakaUniversity Yamadaoka 3-1 Suita Osaka 565-0871Japan.

Capacitation and the acrosome reaction are key phenomena in mammalian fertilization. These phenomena were found more than 60 years ago. However, fundamental questions regarding the nature of capacitation and the timing of the acrosome reaction remain unsolved. Factors were postulated overtime, but as their roles were not verified by gene-disruption experiments, widely accepted notions concemingthe mechanism of fertilization are facing modifications. Today, although in vitro fertilization systems remain our central research tool, the importance of in vivo observations must be revisited. Here, primarily focusing on our own research, I summarize how in vivo observations using gene-manipulated animals have elucidated new concepts in the mechanisms of fertilization.

关键词： Mechanisms fertilization gene-manipulated

Photocatalytic dry reforming of methane by rhodium supported monoclinic TiO_(2)-B nanobelts

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2022年第8期31卷 562-571,I0015页

作者： masaru Kushida Akira Yamaguchi Masahiro Miyauchi School of Materials and Chemical Technology Tokyo Institute of Technology2-12-1 OokayamaMeguro-kuTokyo 152-8552Japan

The conversion of methane and carbon dioxide into syngas(dry reforming of methane;DRM)has attracted attention owing to the potential to reuse greenhouse *** dioxide(TiO_(2))-based photocatalysts,which have been widely commercialized owing to their high efficiency,non-toxicity,and low cost,are strongly desired in ***,we report a monoclinic-phase TiO_(2)-B nanobelts-supported rhodium(Rh/TiO_(2)-B nanobelts)catalyst that efficiently promotes DRM under ultraviolet light irradiation at low *** holes in the TiO_(2)-B nanobelts were used to oxidize methane,while the electrons were trapped in rhodium to reduce carbon ***/TiO_(2)-B nanobelts exhibited considerably higher durability and activity than Rh-loaded conventional TiO_(2)(anatase and rutile),owing to the lattice and/or surface oxygen reactivity in TiO_(2)-B nanobelts,which was suggested by X-ray photoelectron spectroscopy measurements and photocatalytic performance tests under an atmosphere of methane *** study paves the path for the effective utilization of methane by constructing active TiO_(2)-based nanometal photocatalysts.

关键词： Photocatalysis Dry reforming of methane Greenhouse gas conversion Gas-phase reaction Titanium dioxide TiO_(2)-B

Stimulation by nizatidine,a histamine H_2-receptor antagonist,of duodenal HCO_3^-secretion in rats:relation to anti-cholinesterase activity

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2000年第5期6卷 651-658页

作者： Koji Takeuchi Shoji Kawauchi Hideo Araki Shigeru ueki Osamu Furukawa Department of Pharmacology and Experimental Therapeutics Kyoto Pharmaceutical UniversityMisasagiYamashinaKyoto 607-8414Japan CURE Bldg.114Suite 217 West LA VAMC 11301 Wilshire Blvd.Los AngelesCA 90073

AIM To examine whether nizatidine stimulates duodenal HCO_3^- secretion in rats by inhibiting AChE activity. METHODS Under pentobarbital anesthesia,a proximal duodenal loop was perfused with saline,and the HCO_3 secretion was measured at pH 7.0 using a pH-stat method and by adding 10mM ***,neostigmine,carbachol or famotidine was administered *** a single injection. RESULTS Intravenous administration of nizatidine(3-30 mg/kg)dose-dependently increased duodenal HCO_3^- secretion,and the effect at 10mg/kg was equivalent to that obtained by carbachol at 0.01 mg/*** nizatidine action was observed at the same dose range that inhibited acid secretion and enhanced gastric motility,mimicked by *** of neostigmine(0.03 mg/kg),and significantly attenuated by bilateral vagotomy and prior s.c. administration of atropine but not by indomethacin,a cyclooxygenase inhibitor,or N^G-nitro-L-arginine methyl ester,a NO synthase *** HCO_3^- secretory response to acetylcholine(0.001 mg/kg)was significantly potentiated by the concurrent administration of nizatidine(3mg/kg,i.v.).The IC_(50)of nizatidine for AChE of rat erythrocytes was 1.4×10^(-6)M,about 12 times higher than that of *** famotidine(>10^(-3)M, 30mg/kg,i.v.)nor cisapride(> 10^(-3)M, 3mg/kg,i.v.)had any influence on AChE activity or duodenal HCO_3^- *** damage induced by acid perfusion(100 mM HCI for 4 h)in the presence of indomethacin was significantly prevented by nizatidine and neostigmine,at the doses that increased the HCO_3^- secretion. CONCLUSION Nizatidine stimulates duodenal HCO_3^- secretion,in both vagal-dependent and atropine-sensitive manners,and the action is associated with the anti-AChE activity of this agent.

关键词： nizatidine histamine H_2 receptor blockaders duodenal HCO_3^-secretion cholinesterase inhibitors rats

Velocity Measurement of Induced Flow by a Laser Focusing Shock Wave

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Thermal Science 2006年第1期15卷 48-53,26页

作者： Hiroyuki HIRAHARA masaru FUJINAMI Masaaki KAWAHASHI Department of Mechanical Engineering Saitama University 255 Shimo-Okubo Sakura Saitama 338-8570Japan. Graduate School of Science and Engineering Saitama University Japan

The objective of this study is to apply the shock wave for control in a micro channel. The shock wave was generated by a laser focusing of pulsed laser beam in the channel. Using a pulse laser to generate a shock wave, a non-stationary flow was induced in the small space between the parallel plates. The spherical and cylindrical shock propagations were observed with schlieren method. The shock Mach number decreases with time and approaches to unity. As reported in the previous investigations, the shock speed was attenuated in a short distance and time. In the present experiment, It was not found a remarkable difference in the shock speed between the spherical and cylindrical shock experiments. Subsequently, the flow induced by the cylindrical shock wave was studied using PIV technique. A smoke tracer was used in the experiment and its velocity was measured within 100 μs. A numerical simulation was carried out to investigate the momentum relaxation between the gas and smoke particle. A suitable shock initiation model was introduced in the simulation. The experimental results show that a wide acceleration and deceleration zone exist behind the shock wave. Also, the relaxation distance in the experimental data is much longer than that in numerical simulation.

关键词： micro-blast wave laser focusing flow visualization PIV.