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Background: FilGAP is a Rac GTPase-activating protein, but regulation via phosphorylation has not been previously characterized. Results: Phosphorylation of FilGAP at serine 402 is necessary to activate FilGAP to suppress cell spreading on fibronectin. Conclusion: Serine 402 is a critical phosphorylation site to regulate FilGAP activity. Significance: This study showed that regulation of FilGAP by phosphorylation may play a role in integrin-mediated cell adhesion on fibronectin.

The spatial variation of the growth rate on mesa-etched GaAs (1̄1̄1̄)B substrates during molecular beam epitaxy of GaAs is measured from the period of the reflection high-energy electron diffraction (RHEED) intensity oscillation using in situ scanning microprobe RHEED. The surface diffusion length of Ga adatoms on the (1̄1̄1̄)B surface is determined from the spatial variation of the growth rate. The surface diffusion length on the (1̄1̄1̄)B surface increases as the substrate temperature is raised or the arsenic pressure is decreased. The typical value of the diffusion length is about 10 μm at a substrate temperature of 580 °C and an arsenic pressure of 5.7×10−4 Pa, which is an order of magnitude larger than that on the (100) surface along the [011] direction. The activation energy of the surface diffusion length changes with the surface reconstruction. Anisotropic diffusion, as reported for the (100) surface, is not observed on the (1̄1̄1̄)B surface.

Systematic measurements were carried out on the surface-diffusion length of Ga adatoms during the molecular-beam epitaxy of GaAs in the presence of hydrogen atoms (H⋅) or hydrogen molecules (H2). The spatial variation of the growth rate on the (100) surface adjacent to the (111)A surface was measured from the period of the reflection high-energy electron diffraction (RHEED) intensity oscillations using in situ scanning microprobe RHEED. The surface-diffusion length of Ga adatoms, which was derived from the spatial variation of the growth rate, becomes larger along with an increase in the H⋅ or H2 pressure. It also increases as the substrate temperature is raised under H⋅ or H2 pressure. The diffusion length in the case of H⋅ introduction is larger than that in the case of H2 introduction.

Plasmonic nanoparticles, such as gold nanoparticles (AuNPs), have been actively applied in solar vapor generation for seawater desalination and water purification, owing to their photothermal heating performances. Such nanoparticles have been frequently anchored within porous supporting materials to ensure easy handling and water absorption. However, there has been limited progress in improving the transport efficiency of light to nanoparticles within porous supports to achieve more effective photothermal heating. Here, we show an enhanced light absorption of AuNPs by supporting on a cellulose paper with tailored porous structures for efficient photothermal heating. The paper consists of AuNP-anchored cellulose nanofibers and cellulose pulp as the top and bottom layers, respectively, which provides dual-layered porous nano-microstructures in the perpendicular direction. Then, the bottom layer with pulp-derived microstructures reflects the transmitted light back to AuNPs within the top layer, which improves their light absorptivity. Thus, under 1 sun illumination, the dual-layered paper demonstrates superior performance in photothermal heating (increases from 28 C to 46 C) and solar vapor generation (1.72 kg m À2 h À1 ) compared with the single-layered AuNP-anchored cellulose nanofiber paper even at the same AuNP content. Furthermore, the water evaporation rate per AuNP content of the dual-layered paper is more than 2 times higher than those of the state-of-the-art AuNPanchored porous materials under the same light irradiation. This strategy enables the efficient use of precious plasmonic nanoparticles for further development of solar vapor generation. † Electronic supplementary information (ESI) available: X-ray diffraction pattern of the AuNP@cellulose nanober paper; surface temperature of cellulose nanober paper and AuNP@cellulose nanober paper over time during surface temperature measurement under 1.0 kW m À2 irradiation; UV-vis-NIR transmittance and reectance spectra of AuNP@cellulose nanober paper and AuNP@cellulose nanober/pulp paper; UV-vis-NIR reectance spectra of pulp paper with different pulp content and absorption spectra of AuNP@cellulose nanober/pulp paper with different pulp content; surface temperature of AuNP@cellulose nanober paper and AuNP@cellulose/pulp paper over time during surface temperature measurement under 1.0 kW m À2 irradiation. See