Label-free detection of melittin binding to a membrane using electrochemical-localized surface plasmon resonance

Localized surface plasmon resonance (LSPR) and electrochemistry measurements connecting to core-shell structure nanoparticle are successfully exploited in a simultaneous detectable scheme. In this work, the surface plasmon band characterizations of this nanostructure type are initially examined by controlling the core size of the silica nanoparticle and shell thickness of the deposited gold. These results clearly show that when the shell thickness is increased, keeping the core size constant, the peak wavelength of the LSPR spectra is shifted to a shorter wavelength and the maximum of peak intensity is achieved at a particular shell thickness. On the basis of this structure, we present a membrane-based nanosensor for optically detecting the binding of peptide toxin melittin to hybrid bilayer membrane (HBM) and electrochemically assessing its membrane-disturbing properties as a function of concentrations. It will open up the way to detect functionally similar protein toxins and other membrane-targeting peptides with the intension of integrating this chip into a microfluid and expanding it into multiarray format.     

Personalized assessment of oxidative cellular damages associated with diabetes using erythrocytes adhesion assay

Increased generation of reactive oxygen species (ROS) is recognized as a prominent feature of vascular dysfunction with diabetes. For self-monitoring of the risk of diabetic complications, we proposed a simple adhesion test of erythrocytes using positively charged surfaces and its adhesion property was found to correlate HbA_1c level in diabetic patients.     

Emission and atmospheric transport of particulate PAHs in Northeast Asia

The emission, concentration levels, and transboundary transport of particulate polycyclic aromatic hydrocarbons (PAHs) in Northeast Asia were investigated using particulate PAH measurements, the newly developed emission inventory (Regional Emission inventory in ASia for Persistent Organic Pollutants version, REAS-POP), and the chemical transport model (Regional Air Quality Model ver2 for POPs version, RAQM2-POP). The simulated concentrations of the nine particulate PAHs agreed well with the measured concentrations, and the results firmly established the efficacy of REAS/RAQM2-POP. It was found that the PAH concentrations in Beijing (China, source region), which were emitted predominantly from domestic coal, domestic biofuel, and other transformations of coal (including coke production), were approximately 2 orders of magnitude greater than those monitored at Noto (Japan, leeward region). In Noto, the PAH concentrations showed seasonal variations; the PAH concentrations were high from winter to spring due to contributions from domestic coal, domestic biofuel, and other transformations of coal, and low in summer. In summer, these contribution were decrease, instead, other sources, such as the on-road mobile source, were relatively increased compared with those in winter. These seasonal variations were due to seasonal variations in emissions from China, as well as transboundary transport across the Asian continent associated with meteorological conditions.     

Fabrication of High-Quality Co2FeSi/SiOxNy/Si(100) Tunnel Contacts Using Radical-Oxynitridation-Formed SiOxNy Barrier for Si-Based Spin Transistors

A high-quality Co₂FeSi (CFS)/SiO _x N _y /Si tunnel junction was fabricated, in which the SiO _x N _y barrier layer was formed by radical oxynitridation of an Si(100) substrate and the CFS electrode was formed by silicidation of an Fe/Co/amorphous-Si multilayer deposited on the barrier layer. The ultrathin SiO _x N _y barrier layer completely blocked diffusion of Co and Fe atoms into the Si substrate during rapid thermal annealing (RTA) for the silicidation. X-ray diffraction investigations clarified that the CFS film on the ultrathin SiO _x N _y barrier layer exhibited a highly (110)-oriented texture structure and that the film had the L2₁ structure with a high degree of L2₁ order. High resolution cross-sectional transmission electron microscopy investigations revealed that the CFS/SiO _x N _y interface was atomically flat and that the crystal lattice of the CFS film was directly grown on the SiO _x N _y surface without degradation of the crystallinity at the interface.     

合肥地区大气水汽标高变化特征的统计研究

根据合肥站四年整层大气水汽含量和地面水汽密度ρ0的晴天观测资料,统计分析了该地区大气水汽标高H的变化特征.结果表明; H的年变化特征为夏季最大,冬季最小,春、秋季节相差很小;季节平均水汽标高值和季节平均地面气温呈高度正相关;各个季节水汽标高的日变化特征均为双谷型,最大值出现在下午16:00左右,两个低谷分别出现在上午08:00和夜间20:00左右;上午06:00至下午16:00,H的时平均值与对应ρ0的时平均值呈高度负相关.     

Flow-induced vibrations in closed side branch pipes and their attenuation methods

Some problems due to flow-induced vibrations related to closed side branch pipes have been observed in thermal and nuclear power plants. Fluctuating pressure generated in the main pipes was unusually, acoustically excited in closed side branch pipes, and intense vibrations were caused at pipes and components. For example, flow-excited acoustic resonance in closed side branches of stub pipes of safety relief valves caused the failure of steam dryers in the United States Quad City Unit 2 nuclear power plant. Furthermore, there was a possibility that residual air or gas in a closed side branch pipe unexpectedly caused severe vibrations of low frequency in the feed water piping system. We have investigated the root cause and influence of air on severe vibrations. Intense fluctuating pressure was often caused by water hammer due to valve closure and it became larger in the closed side branch pipes. We showed that an additional side branch with an orifice was very effective to suppress the flow-induced acoustic resonance. Design methods of the orifice to attenuate fluctuating pressure generated by water hammer were presented considering Mach number, the pressure loss coefficient of orifice and the intensity of particle velocity. Moreover, suitability of the characteristic curve method was confirmed for evaluation of the attenuation effect of an orifice on fluctuating pressure generated by water hammer. Finally, we considered some flow-induced vibration problems related to closed side branch pipes and their attenuation methods.