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Ogi H., Masuda S., Nagakubo A., et al. Physical Review B, 93(2), 024112, 2016. Copyright 2016 by the American Physical Society., Surface waves are often excited by interdigitated transducers consisting of many nanostrips attached on a substrate, and it has been recognized that the mass and stiffness of the attached nanostrips affect surface-wave resonances to some extent. Here, we reveal the more noticeable influence of the interfacial stiffness between strips and substrate at high frequencies. This influence is confirmed by exciting and detecting surface-wave resonances up to ∼6 GHz by picosecond ultrasound spectroscopy. The resonance frequency significantly decreases and attenuation increases as the interfacial stiffness decreases for silicon substrate. However, low-attenuation branches appear along the Rayleigh-wave-resonance dispersion curve for silica substrate, and the resonance frequencies remain nearly identical to those of the Rayleigh waves. Previous models fail to reproduce these surface-wave resonance behaviors. The proposed theoretical model, involving the interfacial stiffness, consistently explained them, indicating the importance of the interface bond strength in designing surface-wave resonators.

An ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) simulator is described which is designed to simulate visible, near infrared, and thermal infrared (TIR) bands. The ASTER simulator will be applied to geological mapping, refinement of the specifications for ASTER, exploration of the mid-wavelength infrared spectral region, and climatic modeling.

In order to investigate the occurrence of several cases of supposed or suspected infection of malaria after transfusion of preserved blood, the author studied survival of plasmodia in preserved blood in the following experiments, using mainly Plasmodium berghei (Vincke and Lips) in mice and Plasmodium vivax in humans.1. Plasmodium berghei seemed to preserve its infectivity to mice up to the 3rd day in stored blood after inoculation with anticoagulant Formula B, up to the 2nd day in the same with anticoagulant Formula A and up to the 5th day with simple sodium citrate.2. The infectivity of P. berghei seemed to depend upon the dose of the pathogens.3. In using Plasmodium vivax to human for therapeutic purpose, 2 of 4 recipients showed positive symptoms of infection, who received the contaminated blood preserved with ACD Formula B for 4 days. The incubation period in the other 2 patients was 16 and 17 days after the inoculation respectively.