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We demonstrate the value of the thermotolerant yeast Issatchenkia orientalis as a candidate microorganism for bioethanol production from lignocellulosic biomass with the goal of consolidated bioprocessing. The I. orientalis MF-121 strain is acid tolerant, ethanol tolerant, and thermotolerant, and is thus a multistress-tolerant yeast. To express heterologous proteins in I. orientalis, we constructed a transformation system for the MF-121 strain and then isolated the promoters of TDH1 and PGK1, two genes that were found to be strongly expressed during ethanol fermentation. As a result, expression of beta-glucosidase from Aspergillus aculeatus could be achieved with I. orientalis, demonstrating successful heterologous gene expression in I. orientalis for the first time. The transformant could convert cellobiose to ethanol under acidic conditions and at high temperature. Simultaneous saccharification and fermentation (SSF) was performed with the transformant, which produced 29 g l(-1) of ethanol in 72 h at 40 degrees C even without addition of beta-glucosidase when SSF was carried out in medium containing 100 g l(-1) of microcrystalline cellulose and a commercial cellulase preparation. These results suggest that using a genetically engineered thermotolerant yeast such as I. orientalis in SSF could lead to cost reduction because less saccharification enzymes are required.

We developed a high resolution Imaging Plate (IP) with a transparent support and a reading system that can detect emissions from dual sides of the IP to improve the image quality of the CR mammography. And we proposed an addition method using the filtering processing in real space in order to achieve optimum addition in all the spatial frequencies. The image quality of the system was evaluated by NEQ and CD-MAM phantom. Furthermore we separated the noise component that consisted of X-ray photon noise, light photon noise, and the structural noise of the IP utilizing laser power dependency of the amount of emissions and the Wiener Spectrum. By using the above reading system and the addition method, NEQ of the system was improved by 40%-50% compared to the latest CR mammography system. We confirmed by use of CD-MAM that the detectability of the image in this reading system was remarkably improved. The noise analysis showed that the ratios of the light photon noise at ic/mm of the front side image and the back side image were about 15% and 40%, respectively, and according as the spatial frequency became higher the ratio of the light photon noise increased.

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