Electrochemical protein chip with arrayed immunosensors with antibodies immobilized in a plasma-polymerized film

An electrochemical protein chip was microfabricated. A thin-film three-electrode system, including an array of 36 platinum working electrodes, a set of thin-film Ag/AgCl electrodes, and platinum auxiliary electrodes, was integrated on a glass substrate. Capture antibodies were immobilized in a 4.5-nm-thick double layer of a hexamethyldisiloxane plasma-polymerized film. Because of their highly cross-linked network structure, the capture antibodies could be firmly immobilized. No nonspecific adsorption was observed during a series of procedures to detect target proteins, and electrochemical cross talk between neighboring sites was negligible. The sandwich immunoassay was conducted on a single chip using model proteins, alpha-1-fetoprotein and beta2-microglobulin. A distinct current increase following the oxidation of hydrogen peroxide produced by the enzymatic reaction of glucose oxidase was observed, which indicates that the capture proteins could actually bind the target proteins. Two kinds of protein were detected independently on multiple sites with respective capture antibodies.     

The influence of moving auditory stimuli on standing balance in healthy young adults and the elderly

The maintenance of postural balance depends on effective and efficient feedback from various sensory inputs. The importance of auditory inputs in this respect is not, as yet, fully understood. The purpose of this study was to analyse how the moving auditory stimuli could affect the standing balance in healthy adults of different ages. The participants of the study were 12 healthy volunteers, who were divided into two age categories: the young group (mean = 21.9 years) and the elderly group (mean = 68.9 years). The instrument used for evaluation of standing balance was a force plate for measuring body sway parameters. The toe pressure was measured using the F-scan Tactile Sensor System. The moving auditory stimulus produced a white-noise sound and binaural cue using the Beachtron Affordable 3D Audio system. The moving auditory stimulus conditions were employed by having the sound come from the right to left or vice versa at the height of the participant's ears. Participants were asked to stand on the force plate in the Romberg position for 20 s with either eyes opened or eyes closed for analysing the effect of visual input. Simultaneously, all participants tried to remain in the standing position with and without auditory stimulation that the participants heard from the headphone. In addition, the variables of body sway were measured under four conditions for analysing the effect of decreased tactile sensation of toes and feet soles: standing on the normal surface (NS) or soft surface (SS) with and without auditory stimulation. The participants were asked to stand in a total of eight conditions. The results showed that the lateral body sway of the elderly group was more influenced than that of the young group by the lateral moving auditory stimulation. The analysis of toe pressure indicated that all participants used their left feet more than their right feet to maintain balance. Moreover, the elderly had the tendency to be stabilized mainly by use of their heels. The young group were mainly stabilized by the toes of their feet. The results suggest that the elderly may need a more appropriate stimulus of tactile and auditory sense as a feedback system than the young for maintaining and control of their standing postures.     

Efficient High-Pulse-Energy Green-Beam Generation by Intracavity Frequency Doubling of a Quasi-Continuous-Wave Laser-Diode-Pumped Nd:YAG Laser

A 50-mJ green beam was generated at a 1-kHz repetition rate by intracavity frequency doubling of a quasi-cw laser-diode-pumped Nd:YAG laser. The green laser was used for 12-mJ fourth-harmonic beam generation with a CsLiB(6)O(10) crystal.     

Origin of sennosides in health teas including Malva leaves

The aim of this study is to clarify whether sennosides are contained in the leaf of Malva verticillata L., and then to clarify the source of sennosides in health teas including malva leaves. The identification and determination of sennosides were performed with thin layer chromatography and high performance liquid chromatography. The leaf of Malva verticillata L. did not contain sennosides A or B and could be easily distinguished from senna leaf. Our previous report showed that sennosides are contained in weight-reducing herbal teas including malva leaves, and that senna leaf is a herbal component in some teas. Furthermore, in 10 samples of health tea including malva leaves that were bought last year, the smallest amount of sennosides was 6.1 mg/bag, and all health teas including malva leaves contained the leaf and midrib of senna. We suggest that sennosides A and B are not contained in the leaf of Malva verticillata L., and that the sennosides in health teas including malva leaves are not derived from malva leaf but from senna leaf.     

Evaluation of 4-nonylphenols and 4-tert-octylphenol contamination of fish in rivers by laboratory accumulation and excretion experiments

Laboratory accumulation and excretion experiments of 4-nonylphenols (NP) and 4-tert-octylphenol (OP) were performed for killifish (Oryzias latipes). The bioconcentration factors (BCF, wet weight) in the whole fish were mean +/- SD of 167 +/- 23 (n = 4) for NP and 261 +/- 62 (n = 4) for OP. The biological half-lives in the whole fish were 9.9 h for NP and 7.7 h for OP. Parallel to the laboratory experiments, field survey on the chemicals contamination for water and ayu fish (Plecoglossus altivelis) from rivers flowing into Lake Biwa was performed. The contamination was not so high in agreement with the laboratory experimental data and the field BCF values (wet weight) in the ayu fish were 21 +/- 15 (n = 8) for NP and 297 +/- 194 (n = 3) for OP.     

Superplasticity of Mg-Zn-Y alloy containing quasicrystal phase processed by equal channel angular pressing

Equal channel angular pressing (ECAP) has been conducted on as-cast Mg-4.3 wt.%Zn-0.7 wt.%Y Mg alloy containing quasicrystal phase at a temperature of 623 K. After 8 ECAP passes, the grain size of the as-cast alloy is decreased from ∼ 120 to ∼ 3.5 μm, and the coarse eutectic quasicrystal phases are broken and dispersed in the alloy. Tensile testing has been performed on the ECAPed Mg-Zn-Y alloy at temperatures of 523 K and 623 K with initial strain rates from 1.5 × 10^− 3 to 1.5 × 10^− 4 s^− 1. The ECAPed alloy exhibits a maximum elongation of about 600% when testing at 623 K using an initial strain rate of 1.5 × 10^− 4 s^− 1. Grain boundary sliding is considered to be the dominant deformation mechanism of the Mg-Zn-Y alloy in the temperature and strain-rate range investigated.     

Disintegration process of yttria-stabilized zirconia ceramics using hydrothermal conditions

Capability of the recycling of high strength and high fracture toughness yttria-stabilized tetragonal zirconia polycrystalline (Y-TZP) sintered body utilizing “low-temperature annealing degradation” phenomenon was investigated. Hydrothermal treatment was employed to induce the phase transformation from tetragonal to monoclinic zirconia and to disintegrate the Y-TZP sintered body. 3 mol% Y₂O₃–ZrO₂ specimens sintered at 1,550 °C and more were disintegrated without leaving the original appearances when the treatment temperature was between 200 °C and 400 °C. The size of the disintegrated fragments of Y-TZP sintered body was much affected by hydrothermal treatment conditions. Only with hydrothermal treatment and simple ball milling, the sintered body was pulverized into the primary particle level. This technique is expected to apply to a sustainable recycling system for the zirconia ceramics, which restrains an energy consumption compared to crushing zirconia using mechanical procedures.     

Fabrication of long-period fibre grating by CO/sub 2/ laser-annealing in fibre-drawing process

Long-period fibre grating (LPFG) writing by a CO₂ laser-annealing using a fibre-drawing process is demonstrated. The fibre in the drawing process was irradiated periodically by a CO₂ laser to modify the refractive index. An LPFG with transmission loss of -10 dB and full width at half-maximum of 13 nm has been fabricated. Results show that the refractive index change was induced by stress at the moment of laser annealing     

Gold nanoparticle distribution monitor for drug delivery system based on optically assisted ultrasonic velocity-change imaging

Optical absorption images of the tissue mimic phantom including gold nanoparticles were obtained by detecting the ultrasonic velocity-change caused by light irradiation. A series of experimental results showed the possibility as a nanoparticle distribution monitor for the drug delivery system.     

Breakdown Characteristics of N2O Gas Mixtures for Quasiuniform Electric Field under Lightning Impulse Voltage

From the viewpoint of mitigating global warming by SF₆ gas, this paper discusses breakdown (BD) characteristics of different electronegative gas mixtures with N₂O gas as SF₆ gas substitutes for quasi-uniform electric field under lightning impulse voltage applications. Experimental results revealed the positive synergism in breakdown strength of binary N₂O / CO₂ and ternary N₂O / CO₂ / O₂ gas mixtures, respectively. Furthermore, N₂ gas as a retardant gas was also mixed with the electronegative gas mixtures in order to reduce the electron energy into the effective levels of electron attachment ability by the electronegative gas mixtures. As the result, ternary N₂O / CO₂ / N₂ and quaternary N₂O / CO₂ / O₂ / N₂ gas mixtures could exhibit the significant synergistic effect in breakdown strength. The optimum mixture rate of quaternary N₂O / CO₂ / O₂ / N₂ gas mixtures was consistent with that estimated by assuming the independent contribution of component gases to the improvement of impulse BD characteristics.