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A photosensing circuit using thin-film transistors (TFTs) for a retinal prosthesis has been developed. First, the TFTs that are low-temperature polycrystalline silicon (poly-Si) TFTs are fabricated on a transparent substrate, which enables us to build an epiretinal implantation system without using any extracorporeal cameras. Then, the photosensing circuit is fabricated by connecting a p/i/n-type phototransistor and a ring oscillator, which provides stimulating current pulses with an oscillation frequency dependent on light illuminance. In particular, the device structure of the p/i/n-type phototransistor is designed well on the basis of device physics, and the configuration of the photosensing circuit on the basis of device characteristics. Subsequently, a wireless power transfer system is architected by magnetic resonance coupling. Finally, a retinal prosthesis is produced by assembling the photosensing circuit and wireless power transfer system, and the stimulating performance is confirmed in an in vitro experiment, which suggests a future possibility of this retinal prosthesis. [ABSTRACT FROM AUTHOR]

Tan spot, a foliar disease of Triticum spp. such as bread wheat (T. aestivum L.) and durum wheat (T. turgidum ssp. durum (Desf.) Husn.) caused by the filamentous fungus Pyrenophora tritici-repentis (Died.) Drechsler leads to serious losses of crop yield and quality in some areas in Japan. P. tritici-repentis is classified into eight races according to the combinations of three necrotrophic effectors, PtrToxA, PtrToxB, and PtrToxC encoded by ToxA, ToxB, and ToxC1, respectively. Race classification has been based on reaction of a differential variety to necrotrophic effectors, which is tested by inoculation. Recent identification of the Tox genes and development of specific DNA markers have enabled us to classify races of P. tritici-repentis collected in Japan by Tox gene genotyping. We found that 17 strains collected from Triticum spp. in Japan were mainly race 1 or 2, because they carried ToxA as a toxin gene by current race classification; wheat genotype tsn1 is resistant to ToxA. Establishment of wheat cultivars carrying tsn1 would be most effective for decreasing agronomic losses caused by the disease in Japan. [ABSTRACT FROM AUTHOR]