The majority of land plants acquire soil nutrients, such as phosphorus and nitrogen, not only through the root surface but also through arbuscular mycorrhizal (AM) fungi. Soybean is the most important leguminous crop in the world. We found 16 ammonium transporter genes in the soybean genome, five of which are AM inducible. Among them, promoter-reporter analysis indicated that the most abundantly transcribed gene, GmAMT4.1, showed specific expression in arbusculated cortical cells. Moreover, the GmAMT4.1-green fluorescent protein fusion was localized on the branch domain of periarbuscular membranes but not on the trunk region, indicating that active ammonium transfer occurs around the arbuscule branches.

Soybeans, the world's leading leguminous crop, establish mutualistic symbiosis with arbuscular mycorrhizal (AM) fungi. AM fungi colonize root cortical cells forming arbuscules, highly branched fungal structures. Arbuscules are enveloped by plant-derived periarbuscular membranes through which plants obtain mineral nutrients, particularly phosphate. We searched the soybean genome in silico, and found 14 Pht1 genes encoding phosphate transporters putatively localized on the plasma membranes. Time course analyses involving reverse transcription-PCR indicated that three of these were AM-inducible. GmPT10 and GmPT11 were induced on fungal colonization, while a transcript of GmPT7 appeared in the later stages. The transport activities of GmPT10 and GmPT11 were confirmed by complementation of a yeast mutant. Soybean hairy roots expressing the GmPT10-green fluorescent protein (GFP) or GmPT11-GFP fusion protein under the control of corresponding promoter showed GFP fluorescence on the branch domains of periarbuscular membranes, indicating that active phosphate transport occurred there.

GmPT7 was originally identified as an arbuscular mycorrhiza-inducible gene of soybean that encodes a member of subfamily I in the PHOSPHATE TRANSPORTER 1 family. In the present study, we established conditions under which a number of dwarf soybean plants complete their life cycles in a growth chamber. Using this system, we grew transgenic soybean with a GmPT7 promoter-β-glucuronidase fusion gene and evaluated GmPT7 expression in detail. GmPT7 was highly expressed in mature, but not in collapsed, arbuscule-containing cortical cells, suggesting its importance in the absorption of fungus-derived phosphate and/or arbuscule development. GmPT7 was also expressed in the columella cells of root caps and in the lateral root primordia of non-mycorrhizal roots. The expression of GmPT7 occurred only in the late stage of phosphorus translocation from leaves to seeds, after water evaporation from the leaves ceased, and later than the expression of GmUPS1-2, GmNRT1.7a and GmNRT1.7b, which are possibly involved in nitrogen export. GmPT7 expression was localized in a pair of tracheid elements at the tips of vein endings of senescent leaves. Transmission electron microscopy revealed that the tip tracheid elements in yellow leaves were still viable and had intact plasma membranes. Thus, we think that GmPT7 on the plasma membranes transports phosphate from the apoplast into the tip elements. GmPT7 knockdown resulted in no significant effects, the function of GmPT7 remaining to be clarified. We propose a working model in which phosphate incorporated in vein endings moves to seeds via xylem to phloem transfer.

4H-SiC has gained attention as a material for advanced power devices. In this paper, we investigate the surface effect on the conversion from screw-type basal plane dislocation (BPD) to threading edge dislocation (TED) using reaction pathway analysis. We find that the constriction of a partial dislocation pair easily occurs in the vicinity of the surface and that the constriction in the Si-face substrate is easier than that in the C-face one. Also, we find that the cross slip of a perfect screw BPD easily occurs in the vicinity of the surface and that the cross slip in the Si-face is easier than that in the C-face. In addition, we reveal that the rate-limiting step of the cross slip is the glide to shuffle-glide mix transition. We also perform molecular dynamics simulations of a perfect screw BPD-TED conversion in an off-cut substrate and confirm that spontaneous conversion occurs even at low temperature (500 K).

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Hot-water-treatment has been adapted to fabricate ultrafine nanoporous palladium-aluminum film from aluminum-palladium alloy film. Using citric acid as a chelating agent, a precipitation of boehmite (aluminum oxide hydroxide, AlOOH) on the nanoporous palladium-aluminum film was suppressed. According to cross-sectional scanning transmission electron microscopy observations, the ligament/pore sizes of the prepared nanoporous film were considerably small (on the order of 10 nm). Since this fabrication method only requires aluminum alloy film and hot-water with chelating agent, the ultrafine nanoporous film can be prepared simply and environmentally friendly.

We conclude that TBG-CDJ might be a prevalent cause of complete deficiency of thyroxine-binding globulin in the Japanese and that TBG-poly probably appeared before the divergence of human races.

It was reported that the lack of the structural stability of semiconductor silicon micro-pattern induced the lateral undulation buckling. Our previous report revealed that the intrinsic stress of the oxide film on the surface of amorphous silicon produced the compressive stress which induces the buckling failure. However, actual amorphous silicon contains hydrogen atoms. Therefore, in this study, we realize the surface oxide film fabrication on hydrogenated amorphous silicon and clarify the relationship between hydrogen concentration and intrinsic stress due to surface oxidation.As a result, regardless the hydrogen concentration, surface oxide layer contains no hydrogen atoms. In addition, it is found that the intrinsic stress is generated in the sub-oxide layer where oxidation process is not completed. As the hydrogen concentration increases, the integral value of the compressive stress decreases linearly. The stress decreases about 30 % when the hydrogen concentration reaches 25 at%. Decrease in the stress would be caused by the sparse silicon structure due to hydrogen atoms and resulting release of the strain due to surface oxidation.