Yoshihiko Hirai

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The application of exogenous proline and glycinebetaine (betaine) confers salt tolerance on plants under salt stress. The effects of exogenous proline and betaine on apoplastic flow in rice plants under saline conditions were investigated using trisodium-8-hydroxy-1,3,6-pyrenetrisulphonic acid (PTS), an apoplastic tracer. Rice plants took up more PTS under(More)
Physiological aspects of acidity stress in plants (synonymous with H(+) rhizotoxicity or low-pH stress) have long been a focus of research, in particular with respect to acidic soils where aluminium and H(+) rhizotoxicities often co-occur. However, toxic H(+) and Al(3+) elicit different response mechanisms in plants, and it is important to consider their(More)
A simple microfabrication method for a controlled-release drug-delivery system has been designed using biodegradable polymeric microchips. Microholes were made in a poly(L-lactic acid) plate and dyes were cast in each well. After drying, the wells were sealed with polymers having different biodegradation rates using a mold that had hollows corresponding to(More)
We propose a new design method for periodic diffraction gratings to be fabricated with direct-writing electron-beam lithography. When the grating has a small period, the proximity effect of electron scattering restricts the grating profile after developing. Our design method optimizes the electron-dose profile and grating profile simultaneously to obtain(More)
This paper describes a new simple process model for photoresist development. The model includes the consideration of chemical reactions between a photoresist and a developer, and takes the developer concentration dependence into account. The model is applied to the design of practical photo-lithography processes to determine development conditions. Through(More)
Salinity significantly increased trisodium-8-hydroxy-1,3,6-pyrenetrisulphonic acid (PTS) uptake and decreased the K(+)/Na(+) ratio in salt-sensitive rice (Nipponbare) but did not markedly in salt-tolerant rice (Pokkali). Proline and glycinebetaine (betaine) suppressed the increase in PTS uptake and the decrease in the K(+)/Na(+) ratio in Nipponbare, but did(More)
A three-dimensional topographical simulator PEACE (Photo and Electron beam lithography Analyzing Computer Engineering system) is developed. One of the difficulties in resist topographical simulation exists due to the threedimensional resist development algorithm. A newly developed algorithm based on the cell removal model provides accurate and stable(More)
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