Amorphous nanosilicas induce consumptive coagulopathy after systemic exposure

We previously reported that well-dispersed amorphous nanosilicas with particle size 70 nm (nSP70) penetrate skin and produce systemic exposure after topical application. These findings underscore the need to examine biological effects after systemic exposure to nanosilicas. The present study was designed to examine the biological effects. BALB/c mice were intravenously injected with amorphous nanosilicas of sizes 70, 100, 300, 1000 nm and then assessed for survival, blood biochemistry, and coagulation. As a result, injection of nSP70 caused fatal toxicity, liver damage, and platelet depletion, suggesting that nSP70 caused consumptive coagulopathy. Additionally, nSP70 exerts procoagulant activity in vitro associated with an increase in specific surface area, which increases as diameter reduces. In contrast, nSP70-mediated procoagulant activity was absent in factor XII-deficient plasma. Collectively, we revealed that interaction between nSP70 and intrinsic coagulation factors such as factor XII, were deeply related to nSP70-induced harmful effects. In other words, it is suggested that if interaction between nSP70 and coagulation factors can be suppressed, nSP70-induced harmful effects may be avoided. These results would provide useful information for ensuring the safety of nanomaterials (NMs) and open new frontiers in biological fields by the use of NMs.     

Vacuum Insulation and Achievement of 980 keV, 185 A/m~2 H-Ion Beam Acceleration at JAEA for the ITER Neutral Beam Injector

Vacuum insulation of 1 MV is a common issue for the HV bushing and the accel- erator for the ITER neutral beam injector (NBI). The HV bushing as an insulating feedthrough has a five-stage structure and each stage consists of double-layered insulators. To sustain 1 MV in vacuum, reduction of electric field at several triple points existing around the double-layered insulators is a critical issue. To reduce electric field simultaneously at these points, three types of stress ring have been developed. In a voltage holding test of a full-scale mockup equipped with these stress rings, 120% of rated voltage was sustained and the voltage holding capability required in ITER was verified. In the MeV accelerator, whose target is the acceleration of a H ion beam of 1 MeV, 200 A/m 2 , the gap between the grid support was extended to suppress breakdowns triggered by electric field concentration at the edge and corner of the grid support. This modi- fication improved the voltage holding capability in vacuum, and the MeV accelerator succeeded in sustaining 1 MV stably. Furthermore, it appeared that the H ions beam was deflected and a part of the beam was intercepted at the acceleration grid. This causes high heat load on the grids and breakdowns during beam acceleration. To suppress the direct interception, a new grid was designed with proper aperture displacement based on a three dimensional beam trajectory analysis. As a result, 980 keV, 185 A/m 2 H ion beam acceleration has been demonstrated, which is close to the ITER requirement.     

Conceptual study of vertical sector transport maintenance for DEMO fusion reactor

The maintenance scheme is a critical issue for DEMO design, and requires high availability of the reactor. The SlimCS, designed in JAEA, adopts the horizontal sector transport hot cell maintenance scheme. In order to determine the most appropriate DEMO reactor maintenance scheme, it is important to assess the various maintenance schemes. In this paper the vertical sector transport maintenance concept is proposed for the first time. In the sector maintenance scheme, the amount of cutting/re-welding of the piping is minimized. The sector including blanket modules and a high-temperature shield was divided into 10° segments in a toroidal direction. The sectors are designed to be removed and re-inserted through upper alternate vertical maintenance ports. In the case of the vertical sector transport maintenance scheme, inter-coil structures could be adopted for use against turnover force in toroidal field (TF) coils. This shows an advantage in DEMO maintenance compared with horizontal sector transport.     

α-gel prepared in sodium methyl stearoyl taurate/behenyl alcohol/water system-characterization of structural changes with water concentration

In this study, the changes in the structural and physicochemical properties of an α-crystalline phase (often called an "α-gel") were assessed in a sodium methyl stearoyl taurate (SMT)/behenyl alcohol/water system. The α-gels were characterized focusing on the effects of the alcohol/surfactant ratio and water concentration. Water molecules solubilized in the interlayer of the α-crystalline phase resulting in expanded interlayer spacing. Beyond the solubilization limit of 85 %, water molecules were trapped in the matrix of the α-crystalline phase in non-equilibrium (i.e., two phases). Accordingly, different self-diffusion coefficients for the solubilized and trapped water molecules were measured using a Fourier transform pulsed gradient spin echo technique to monitor the 1H NMR spectra. It was concluded that the two self-diffusion coefficients correspond to the water solubilized in the interlayer, i.e., "slow water," and trapped in the matrix of the α-crystalline phase, i.e., "fast water."     

Preparation and electrochemical properties of SiO2–non-graphitizable carbon composites as negative electrode materials for Li-ion batteries

SiO₂–non-graphitizable carbon composites were prepared by pyrolysis of a mixture of ethyl cellulose and nano-sized SiO₂. The composite electrode showed high reversibility in insertion and/or extraction reactions of Li ions at potentials below 1 V with little hysteresis after the 2nd cycle, whereas a large irreversible capacity was observed in the 1st cycle. This reversible capacity increased with increasing SiO₂ content above 5 wt%. Li ion transfer at the interface between a composite electrode and an electrolyte was studied by ac impedance spectroscopy. In the Nyquist plots, a semi-circle that was assigned to charge-transfer resistance (R _ct) because of Li ion transfer across the interface between the composite electrode and electrolyte appeared at potentials below 1 V. The values of R _ct decreased with increasing SiO₂ content. These results indicate that both a decrease in R _ct and an increase in reversible capacity can be achieved by use of SiO₂–non-graphitizable carbon composite electrodes; this would lead to Li-ion batteries with higher power and energy density.     

Fabrication of colorless organic materials exhibiting white luminescence using normal and excited-state intramolecular proton transfer processes

Organic, white luminescent materials were fabricated using a mixture of proton-transfer and nonproton-transfer fluorophores. 2'-Methoxy and 2'-hydroxy derivatives of 2-phenylimidazo[1,2-a]pyridine (PIP) have similar UV-absorption properties; however, they exhibit mechanistically different luminescence respectively ascribable to the normal (～420 nm) and excited-state intramolecular proton transfer processes (～530 nm) in the solid state. UV-irradiation of mixed solids excites both components concurrently and results in efficient white luminescence composed of two independent emissions without involving energy transfer process. White luminescent solids are easily transformed into vapor-deposited films under mild conditions, and a colorless and transparent thin film by dissolving in PMMA.     

Effect of surface properties of silica nanoparticles on their cytotoxicity and cellular distribution in murine macrophages

In this study, complexes composed of poly-l-tyrosine (pLT) and single-walled carbon nanotubes (SWCNTs) were produced and the dispersibility of the pLT/SWCNT complexes in water by measuring the ζ potential of the complexes and the turbidity of the solution were investigated. It is found that the absolute value of the ζ potential of the pLT/SWCNT complexes is as high as that of SWCNTs modified with double-stranded DNA (dsDNA) and that the complexes remain stably dispersed in the water at least for two weeks. Thermogravimetry analysis (TGA) and visualization of the surface structures of pLT/SWCNT complexes using an atomic force microscope (AFM) were also carried out.     

Indoline-based donor molecule for efficient co-evaporated organic photovoltaics

We demonstrated the use of an asymmetrical donor–acceptor-type indoline dye—D131, developed for dye-sensitized solar cells, as an electron donor and fullerene C₇₀ as an electron acceptor for thermal co-evaporated bulk-heterojunction organic solar cells (OSCs). In spite of the presence of intermolecular hydrogen bonds among D131 molecules, they can be thermally evaporated in high vacuum at a relatively low temperature of 220 °C. The blend ratio and thickness of the active layer of D131/C₇₀ blend films in OSCs were optimized to achieve a maximum power-conversion efficiency of 4.5% with a short-circuit current of 9.1 mA cm^?2, an open-circuit voltage of 0.89 V, and a fill factor of 0.56 under AM 1.5G solar illumination (100 mW cm^?2), which is the best value reported so far for OSCs based on indoline-based donor materials.