Akira Kawakami

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Fructans are water-soluble fructose oligomers and polymers that are based on sucrose, and have been implicated in protecting plants against water stress. Rice (Oryza sativa L.) is highly sensitive to chilling temperatures, and is not able to synthesize fructans. Two wheat fructan-synthesizing enzymes, sucrose:sucrose 1-fructosyltransferase, encoded by wft2,(More)
Variation in the structures of plant fructans and their degree of polymerization (DP) can be explained as the result of diverse combinations of fructosyltransferases (FTs) with different properties. Although FT genes have been isolated in a range of plant species, sucrose:fructan 6-fructosyltransferase (6-SFT) cDNAs have only been functionally characterized(More)
Fructans can act as cryoprotectants and contribute to freezing tolerance in plant species, such as in members of the grass subfamily Pooideae that includes Triticeae species and forage grasses. To elucidate the relationship of freezing tolerance, carbohydrate composition and degree of polymerization (DP) of fructans, we generated transgenic plants in the(More)
BACKGROUND For the diagnosis of seasonal influenza, clinicians rely on point-of-care testing (POCT) using commercially available kits developed against seasonal influenza viruses. However, POCT has not yet been established for the diagnosis of pandemic influenza A virus (H1N1pdm) infection due to the low sensitivity of the existing kits for H1N1pdm. (More)
Ear rot with white or pink mold was found on corn (Zea mays L.). A species of Fusarium, not registered previously as a pathogen causing Gibberella ear rot of corn in Japan, was isolated from the rotted ear. The isolates, identified as F. asiaticum based on morphological characteristics and nucleotide sequences, caused white or pink mold on corn ear after(More)
— We are developing a low noise heterodyne receiver at 3THz band for applications of atmospheric and astronomical research and for application of wireless communications. We have developed a phase-locking system of a terahertz quantum cascade laser (THz-QCL) by using a hot electron bolometer mixer. The THz-QCL was locked to terahertz reference generated by(More)
We present the first experimental results on waveguide-type all-NbN SIS receivers fabricated on MgO substrates designed in a frequency range from 780 to 960 GHz. The receiver has a resonant distributed SIS junction one wavelength long at 870 GHz as the tuning circuit and a diagonal feed horn. The mixer chip was fabricated with accuracies of less than 10 im(More)
SUMMARY We report on progress in the development of high current density NbN/AlN/NbN tunnel junctions for application as submillimeter wave SIS mixers. A ultra-high current density up to 120 kA/cm 2 , roughly two orders of magnitude larger than any reported results for all-NbN tunnel junctions, was achieved in the junctions. The magnetic field dependence(More)
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