Akita Prefectural University

About: Akita Prefectural University is a education organization based out in Akita, Japan. It is known for research contribution in the topics: Magnetic field & Starch. The organization has 1631 authors who have published 3107 publications receiving 45764 citations. The organization is also known as: Akita kenritsu daigaku.

Amyloplast-Localized SUBSTANDARD STARCH GRAIN4 Protein Influences the Size of Starch Grains in Rice Endosperm

Abstract: Starch is a biologically and commercially important polymer of glucose and is synthesized to form starch grains (SGs) inside amyloplasts. Cereal endosperm accumulates starch to levels that are more than 90% of the total weight, and most of the intracellular space is occupied by SGs. The size of SGs differs depending on the plant species and is one of the most important factors for industrial applications of starch. However, the molecular machinery that regulates the size of SGs is unknown. In this study, we report a novel rice (Oryza sativa) mutant called substandard starch grain4 (ssg4) that develops enlarged SGs in the endosperm. Enlargement of SGs in ssg4 was also observed in other starch-accumulating tissues such as pollen grains, root caps, and young pericarps. The SSG4 gene was identified by map-based cloning. SSG4 encodes a protein that contains 2,135 amino acid residues and an amino-terminal amyloplast-targeted sequence. SSG4 contains a domain of unknown function490 that is conserved from bacteria to higher plants. Domain of unknown function490-containing proteins with lengths greater than 2,000 amino acid residues are predominant in photosynthetic organisms such as cyanobacteria and higher plants but are minor in proteobacteria. The results of this study suggest that SSG4 is a novel protein that influences the size of SGs. SSG4 will be a useful molecular tool for future starch breeding and biotechnology.

Design and experimental results of small-scale rotary engines

Abstract: A research project is currently underway to develop small-scale internal combustion engines fueled by liquid hydrocarbons. The ultimate goal of the MEMS Rotary Internal Combustion Engine Project is to develop a liquid hydrocarbon fueled MEMS-size rotary internal combustion micro-engine capable of delivering power on the order of milli-watts. This research is part of a larger effort to develop a portable, autonomous power generation system with an order of magnitude improvement in energy density over alkaline or lithium-ion batteries. The rotary (Wankel-type) engine is well suited for the fabrication techniques developed in the integrated chip (IC) community and refined by the MicroElectroMechanical Systems (MEMS) field. Features of the rotary engine that lend itself to MEMS fabrication are its planar construction, high specific power, and self-valving operation. The project aims at developing a "micro-rotary" engine with an 3 epitrochoidal-shaped housing under 1 mm in size and with a rotor swept volume of 0.08 mm 3. To investigate engine behavior and design issues, larger-scale "mini-rotary" engines have been fabricated from steel. Mini-rotary engine chambers are approximately 1000 mm 3 to 1700 mm 3 in size and their displacements range from 78 mm 3 to 348 mm 3. A test bench for the mini-rotary engine has been developed and experiments have been conducted with gaseous-fueled mini-rotary engines to examine the effects of sealing, ignition, design, and thermal management on efficiency. Preliminary testing has shown net power output of up to 2.7 W at 9300 RPM. Testing has been performed using hydrogen-air mixtures and a range of spark and glow plug designs as the ignition source. Iterative design and testing of the miniengine has lead to improved sealing designs. These particular designs are such that they can be incorporated into the fabrication of the micro-engine. Design and fabrication of a first generation meso-scale rotary engine has been completed using a SiC molding process developed at Case Western Reserve University. The fabrication of the micro-rotary engine is being conducted in U.C. Berkeley's Microfabrication Laboratory. Testing of the mini-engine has lead to the conclusion that there are no fundamental phenomena that would prevent the operation of the micro-engine. However, heat loss and sealing issues are key for efficient operation of the micro-engine, and they must be taken into account in the design and fabrication of the micro-rotary engine. The mini-rotary engine design, testing, results and applications will be discussed in this paper. NOMENCLATURE