β-Sitosteryl (6'-O-linoleoyl)-glucoside of soybean (Glycine max L.) crude extract inhibits Y-family DNA polymerases

In the screening of selective DNA polymerase (pol) inhibitors, we isolated an acylated steryl glycoside, β-sitosteryl (6'-O-linoleoyl)-glucoside (compound 1), from the waste extract of soybean (Glycine max L.) oil. This compound exhibited a marked ability to inhibit the activities of eukaryotic Y-family pols (pols η, ι and κ), which are repair-related pols. Among mammalian Y-family pols, the activity of mouse pol κ was most strongly inhibited by compound 1, with an IC(50) value of 10.2 μM. On the other hand, compound 1 had no effect on the activities of other eukaryotic pols such as A-family (pol γ), B-family (pols α, δ, and ε), or X-family (pols β, λ and terminal deoxynucleotidyl transferase) pols. In addition, compound 1 had no effect on prokaryotic pols or other DNA metabolic enzymes such as calf primase of pol α, T7 RNA polymerase, T4 polynucleotide kinase, or bovine deoxyribonuclease I. Compound 1 consists of 3 groups: β-sitosteryl (compound 2), linoleic acid (compound 3), and D-glucose (compound 4). Compound 3 inhibited the activities of all mammalian pols tested, but compounds 2 and 4 did not have any effect on the tested pols. Kinetic studies showed that the inhibition of pol κ activity by compound 1 was noncompetitive with both the DNA template-primer and nucleotide substrate, whereas compound 3-induced inhibition was competitive with the DNA template-primer and noncompetitive with the nucleotide substrate. The relationship between the structure of compound 1 and the selective inhibition of eukaryotic Y-family pols is discussed.     

Verification of screening level for decontamination implemented after Fukushima nuclear accident

The screening level for decontamination that has been applied for the surface of the human body and contaminated handled objects after the Fukushima nuclear accident was verified by assessing the doses that arise from external irradiation, ingestion, inhalation and skin contamination. The result shows that the annual effective dose that arises from handled objects contaminated with the screening level for decontamination (i.e. 100 000 counts per minute) is <1 mSv y(-1), which can be considered as the intervention exemption level in accordance with the International Commission on Radiological Protection recommendations. Furthermore, the screening level is also found to protect the skin from the incidence of a deterministic effect because the absorbed dose of the skin that arises from direct deposition on the surface of the human body is calculated to be lower than the threshold of the deterministic effect assuming a practical exposure duration.     

Pressure‐Driven Eu2+‐Doped BaLi2Al2Si2N6: A New Color Tunable Narrow‐Band Emission Phosphor for Spectroscopy and Pressure Sensor Applications

A series of BaLi₂Al₂Si₂N₆ (BLASN): xEu²⁺ phosphors are successfully synthesized and their crystal structure and luminescence properties under varying hydrostatic pressures are reported herein. Structure variation is analyzed using in situ high‐pressure X‐ray diffraction and Rietveld refinements. Based on decay curves and Gaussian fitting of emission spectra, the presence of two photoluminescence centers is demonstrated. BaLi₂Al₂Si₂N₆: 0.01Eu²⁺ exhibits an evident peak position shift from 532 to 567 nm with an increase in pressure to ≈20 GPa. The possible factors and mechanisms for the variations are studied in detail. At a pressure of 16 GPa, BLASN: Eu²⁺ realizes a narrow yellow emission with a full width at half maximum of ≈70 nm. The addition of BLASN: Eu²⁺ (16 GPa) to the commercial white light‐emitting diodes combination consisting of an InGaN chip, β‐SiAlON: Eu²⁺, and red K₂SiF₆:Mn⁴⁺, can increase the color gamut by ≈15%, demonstrating the promising potential of pressure‐driven BLASN: Eu²⁺ for wide‐color gamut spectroscopy applications. Moreover, the emission shifts arising from pressure variation and the distinct color changes enable its potential utility as an optical pressure sensor; the material exhibits high pressure sensitivity (dλ/dP ≈ 1.58 nm GPa^?1) with the advantage of visualization.     

Laser-guided discharge characteristics of long air gaps and observation of the discharge process

Laser-guided discharge is promising for protection of power transmission systems against lightning. Several experiments concerning the laser-induced electrical discharge have been performed up to now. However, it is necessary to understand the mechanism of the laser-induced electrical discharge to achieve the laser-triggered lightning. When a high-power laser beam is focused in air, a high degree of ionization is produced as brilliant beams near the focus. In this paper, the electrical discharge induced up to 2-meters with a high-power CO₂ laser focused by a 10-meter focal length mirror is described. Experiments of the laser-guided discharge were carried out by application of an impulse voltage to a rod-rod gap after laser radiation. This paper deals with the effects of delay times and polarity of the impulse voltage on 50 percent flashover voltage characteristics and the observation results of discharge phenomena taken by a still camera, a special camera named ALPS (Automatic Lightning Discharge Progressing Feature Observation System) and an image converter camera.     

Metallization of cross-linked epoxy resins by reduction of polymer-incorporated metal ions

The metallization behavior of the poly(ethylene glycol) diglycidyl ether films cured with 5-(2,5-dioxotetrahydrofuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride (DMCDA) by reduction of polymer-incorporated cobalt chloride or nickel chloride was investigated by means of infra-red spectroscopy, dynamic viscoelastic measurement, X-ray photoelectron spectroscopy, scanning electron microscopy and electron probe microanalysis. For the film containing the metal chloride cured at finally 200 °C for 5 h, the metal ion was homogeneously distributed in the inner part of the film, except that the film surface at the air side had a higher metal ion concentration because of the chelation of the metal ion with carboxylic acid group generated by the reaction of DMCDA with water in air. By the reduction treatment in aqueous sodium borohydride at 20–50 °C, the metal ion migrated to both sides of the film and then reduced to pure metal. The metal layer generated at the air side was thicker than the one at the side of a polypropylene plate used in the preparation of film. The X-ray diffraction analysis of the reduced films revealed that the generated cobalt and nickel were almost amorphous.     

Studies on the δ‐form complex in the syndiotactic polystyrene–organic molecule system. II. Structural investigation of the δ‐form with p‐ and m‐xylene isomers

Syndiotactic polystyrene (sPS) membranes containing different mole fractions of p‐xylene were prepared by a solution‐casting procedure. Complex formation between sPS and xylene was studied by thermogravimetric analysis and Fourier transform infrared spectroscopy. The stability and desorption behavior of the sPS–guest solvent and phase transitions were studied by differential scanning calorimetry. The formation of the δ‐form complex in the presence of different mole fractions of xylene isomers was analyzed and confirmed. The mole fraction of p‐xylene in the dried membrane was found to be higher than that of the corresponding mole fraction in the isomer solvent solution used for casting. This was attributed to the preferential complexing ability of p‐xylene with sPS. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2882–2887, 2003     

System throughput improvement by optimizing timeout for wireless network coding and frame aggregation on CSMA/CA bidirectional two‐hop relaying prototype

This paper reports an outdoor experiment to optimize the timeout of wireless network coding (WNC) and frame aggregation (FA), which are implemented to carrier sense multiple access with collision avoidance (CSMA/CA)‐based wireless two‐hop relay prototype. The system throughput is improved. In the prototype, FA is implemented at the terminal nodes. Timeout function for WNC is available at the relay node and that for FA is available at the terminal nodes. Our outdoor experiment shows that optimizing the timeout values of WNC and FA can improve system throughput by 2.04‐fold compared to the conventional relay without WNC or FA. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Polyoxyethylene oligomer distribution of nonionic surfactants

Thin layer chromatography with a flame ionization detection (TLC-FID) technique was applied to the separation and determination of nonionic surfactants containing oxyethylene (OE) chains. The OE adducts with an average number of 4.2, 6.0 and 8.0 oxyethylene units were separated on Chromarod S-II (Silica gel-coated rods) with double development using benzene:ethyl acetate (6:4) and ethyl acetate:acetic acid:water (8:1:1). OE adducts of nonionic surfactants were well separated by the TLC-FID method using simple and standard techniques that eliminate the need for any chemical modification.     

Stress relaxation of glass-fiber-reinforced rigid polyurethane foam

Flexural stress relaxations were measured for rigid polyurethane foams (PUF) and glass-fiber-reinforced rigid polyurethane foams (FRU). The results were successfully analyzed in terms of the five element Maxwell model: (1) Samples reinforced with longer fibers exhibit reduced stress relaxation and reduced temperature dependency of stress relaxation; (2) The increased expansion ratio reduces the flexural modulus of both reinforced and non-reinforced materials, but the stress relaxation tends to increase greatly at the higher temperature for PUF, while not so greatly for FRU; (3) The temperature dependency of E₁ decreases as longer fibers are used to reinforce the polyurethane. The dependency is minimal for the polyurethane reinforced with continuous fibers, where the reinforcing effect is maximal; and (4) The activation energy calculated from τ₂ according to the Arrhenius plot is smaller for the longer fiber reinforced polyurethane foams.