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Presents a study that investigated the influence of electron temperature and of bias on charge build-up caused by electron shading in inductively-coupled plasmas at 2 to 40 mTorr in argon. Background on plasma charging damage to the gate-oxide of metal oxide semiconductor field effect transistors; Measurement of the electron and ion currents going into the silicon substrate through the dielectric structure; Effect of the electron temperature on the floating potential of the sample.

Background/purpose Near-infrared ( NIR) light with high water absorption enables us to visualize the water content distribution appeared in the superficial skin layer. The light penetration depth with the wavelength of 1920 nm is almost 100 μm from the skin surface. Thus, the water distribution in the stratum corneum can be effectively imaged by detecting the wavelength band around 1920 nm. The aim of this article was to measure the time-lapse behavior of the tiny droplet of the moisturizer spreading on the skin surface by imaging in 1920 nm wavelength band for investigating the correlation with the traditional index of the skin condition such as the water content and transepidermal water loss ( TEWL). Methods Experiment is performed with three moisturizer products and seven volunteer subjects. The NIR image is acquired by an originally designed imaging scope equipped with the white light of the strong brightness [super continuum (SC) light], the bandpass filter with the center wavelength of 1920 nm, and the NIR image sensor. A tiny droplet of the moisturizer is put on the surface of the skin and the time-lapse images are saved. Each acquired image is analyzed from a view point of the droplet area and elapsed time for absorption into the skin. The water content and TEWL of all subjects are measured by the conventional electrical method for investigating the relationship with the measured droplet dynamics parameters. Results Elapsed time for moisturizer droplet to be absorbed into the skin, the droplet area just before absorption for three moisturizer products, skin water contents, and TEWL for seven subjects were measured and correlation coefficients for each parameters were calculated. It was found that the skin with higher water contents or lower TEWL absorbed the moisturizer faster and spreads moisturizer wider. Also absorption and spreading speed depend on moisturizer property (moisturizing or fresh) which is originated from the moisturizer constituents. Conclusion The correlation values between the moisturizer dynamics on the skin surface and the traditional index of the skin property were clarified. It was found that the skin with the high water content or low TEWL absorbs the moisturizer droplet fast. The spreading area depends not only on the skin property but on the constituents of the moisturizers. [ABSTRACT FROM AUTHOR]

Background/purpose We investigate the measurement sensitivity for the water content distribution in Near-infrared (NIR) imaging ranging up to 2 μm. Methods To evaluate the sensitivity, our attention is focused to the light penetration depth in the skin tissue because the thickness of a layer where the water content can be varied is very thin and deep light penetration decreases the signal variation. The light penetration depths in the wavelengths of 1300, 1450, and 1920 nm are calculated theoretically based on the Monte Carlo light transport simulation. Results It is clarified that the wavelength of 1920 nm gives the smallest penetration depth. A NIR imaging experiment is demonstrated to verify the difference of imaging sensitivity. The experiment result shows that the NIR image taken at 1920 nm gives the most sensitive measurement of the water content distribution in skin. [ABSTRACT FROM AUTHOR]

Abstract: The sustainable detachment has been achieved in LHD. The line-averaged electron density of the detachment plasmas is typically over 1.0×1020 m−3. The difference in the broad component of the Hα spectral line profiles between the attachment and detachment plasmas has been observed. In attachment, the divertor flux much affects the neutral hydrogen generation and the large inward flow up to 1.5×104 m/s seemed to be due to the reflection is observed. In detachment, the much smaller flow velocity along the sight lines and the lower Doppler temperature are observed. These observations represent the drastic reduction of the divertor flux and the decrease of the edge electron temperature involved with detachment. [Copyright &y& Elsevier]

The magnetohydrodynamic (MHD) activity and the discrete dynamo in high-Θ reversed-field pinch (RFP) discharges are studied through comparisons with those in normal-Θ RFP discharges, where Θ=Bθ(a)/ is the pinch parameter. In high-Θ RFP discharges, the mode coupling of m=1 is enhanced by the high magnetic shear configuration, and the MHD activity is more turbulent as compared with that in normal-Θ RFP discharges. Furthermore, the discrete increase of the toroidal magnetic flux is obviously observable. The increase of the toroidal magnetic flux generated by the discrete dynamo, which has an asymmetric structure in the toroidal direction, is only 1%–2% of the whole toroidal magnetic flux. The experimental results indicate that the discrete dynamo does not play an essential role in the RFP dynamo. [ABSTRACT FROM AUTHOR]

Wide temperature range, from 0 to 85°C, operation of 1.55 μm, 40 Gbit/s InGaAlAs multiple quantum well electro-absorption optical modulators is demonstrated for the first time. [ABSTRACT FROM AUTHOR]

A novel travelling-wave electroabsorption optical modulator, electrically matched for 50 Ω loads of driving circuit drivers, was developed. The scattering parameter of electric reflection (S[sub 11]) from this modulator is less than -20 dB at 20 GHz. It can thus enable a 40 Gbit/s, 2 km SMF transmission with a 0.3 dB penalty at a 1.3 µm wavelength. [ABSTRACT FROM AUTHOR]

We investigated the effectiveness of stroke volume variation (SVV) shown by the Vigileo-FloTrac™ system (Edwards Lifesciences, Irvine, CA) to predict fluid responsiveness in patients undergoing airway pressure release ventilation (APRV). All 80 patients mechanically ventilated in the intensive care unit of our hospital from April to November 2010 were included in this study. After starting APRV, Ringer's lactate solution was administered for 30 minutes. Haemodynamic variables including heart rate, mean arterial pressure, cardiac index (CI), stroke volume index (SVI) and SVV were measured before and after volume loading. SVV before volume loading was significantly correlated with absolute change in SVV (ΔSVV) and percentage change in stroke volume index (ΔSVI) after volume loading (ΔSVV: P<0.05, r2=0.534; ΔSVI: P<0.05, r2=0.217). Of the 80 patients, 38 (47.5%) were responders to intravascular volume expansion (increase in CI≥15%) and 42 (52.5%) were non-responders (increase in CI<15%). Receiver operating characteristic (ROC) curves were generated for SVV and central venous pressure by varying the discriminating threshold of the variable and areas under the ROC curves were calculated. The areas under the ROC curves were 0.793 for SVV (95% confidence interval: 0.709-0.877) and 0.442 for central venous pressure (95% confidence interval: 0.336-0.549), which were significantly different (P<0.05). The optimal threshold value of SVV to discriminate between responders and nonresponders was 14% (sensitivity: 78.9%; specificity: 64.3%). We found that SVV was able to predict fluid responsiveness in patients undergoing APRV with acceptable levels of sensitivity and specificity. [ABSTRACT FROM AUTHOR]

Abstract: We examined the influence of insect cadaver desiccation on the virulence and production of entomopathogenic nematodes (EPNs), common natural enemies of many soil-dwelling insects. EPNs are often used in biological control, and we investigated the feasibility of applying EPNs within desiccated insect cadavers. Desiccation studies were conducted using the factitious host, Galleria mellonella (Lepidoptera: Pyralidae, wax moth larvae) and three EPN species (Heterorhabditis bacteriophora ‘HB1’, Steinernema carpocapsae ‘All’, and Steinernema riobrave). Weights of individual insect cadavers were tracked daily during the desiccation process, and cohorts were placed into emergence traps when average mass losses reached 50%, 60%, and 70% levels. We tracked the proportion of insect cadavers producing infective juveniles (IJs), the number and virulence of IJs produced from desiccated insect cadavers, and the influence of soil water potentials on IJ production of desiccated insect cadavers. We observed apparent differences in the desiccation rate of the insect cadavers among the three species, as well as apparent differences among the three species in both the proportion of insect cadavers producing IJs and IJ production per insect cadaver. Exposure of desiccated insect cadavers to water potentials greater than −2.75kPa stimulated IJ emergence. Among the nematode species examined, H. bacteriophora exhibited lower proportions of desiccated insect cadavers producing IJs than the other two species. Desiccation significantly reduced the number of IJs produced from insect cadavers. At the 60% mass loss level, however, desiccated insect cadavers from each of the three species successfully produced IJs when exposed to moist sand, suggesting that insect cadaver desiccation may be a useful approach for biological control of soil insect pests. [ABSTRACT FROM AUTHOR]

Improvement of the vertical stability of tokamak plasma with only local coils above and below the plasma was observed for the first time. The local coils in triangular shape, named upper and lower triangular (ULT) coils, were installed in TOKASTAR-2, a tokamak-stellarator hybrid device at Nagoya University. The ULT coils generate the effective radial magnetic field B R eff , which is expected to stabilize the plasma vertical position. The region of the plasma position where vertical displacement events (VDEs) did not occur was extended by applying the ULT magnetic field. Stabilization of the plasma vertical position was related to the ratio of the vertical-direction derivative of the effective radial field generated by the ULT coils, ∂ B R eff / ∂ Z , to that of the axisymmetric radial field, ∂ B R / ∂ Z . Moreover, even when VDEs occurred in discharges with the ULT magnetic field, the VDE speed was mitigated by the effect of the ULT magnetic field; the VDE speed increased with ∂ B R / ∂ Z , while decreased with ∂ B R eff / ∂ Z . [ABSTRACT FROM AUTHOR]

Nonparabolic tendency of conduction subbands in InGaAs/InAlAs quantum wells (QWs), lattice-matched to InP, were studied using cyclotron resonance (CR) because its confinement potential was stronger than in InGaAs/InP and GaAs/GaAlAs QWs. Thickness of InGaAs well was 5–10 nm. Barrier thickness was more than 10 nm. Field-scanned pulse CR and wavelength-scanned CR were observed. CR energy changed sublinearly with magnetic field. This curve agreed with our calculation, based on Kane''s three-level band theory and Landau quantization. [Copyright &y& Elsevier]

A rapid growth of magnetic fluctuations resulting from the m=1 and m=2 modes and succeeding stop of rotation of these modes have been found as the precursor phenomena of current termination in the STP-3(M) [Trans. Inst. Elec. Eng. Jpn. 107-B, 469 (1987)] reversed field pinch. By deepening the field reversal at the wall, these precursors disappear and the current duration becomes much longer. It is found that sudden current termination is caused by a rapid growth of resistive tearing modes mainly because of nonlinear coupling of the m=1 mode. [ABSTRACT FROM AUTHOR]

Scanning tunneling microscopy for semiconductor carrier profiling is simulated in three dimensions. By solving the tunnel currents between a probe tip and a sample consistently with the current continuity equations, current-voltage characteristics in good agreement with measurements are obtained. Critical differences from potential-based calculations are observed under depletion and inversion conditions. By preparing a current-concentration table from samples with uniform concentrations, the carrier profile in p-n junction samples can be extracted by estimating the concentrations at each position. It is revealed that the tunnel current is spread around the depletion region of a p-n junction, which affects the results dramatically. When a proposed simulation is iteratively used with measurements, impurity profile extraction is possible even in the depletion region. [ABSTRACT FROM AUTHOR]

We describe the observation of stimulated emissions by current injections into a silicon quantum well. The device consists of a free standing membrane with a distributed feedback resonant cavity fabricated by state-of-the-art silicon processes. The emission spectra have multimode structures peaked in the near-infrared region above the submilliampere threshold currents at room temperatures. Consequently, electronics and photonics should be able to be converged on chips by using silicon quantum well laser diodes. [ABSTRACT FROM AUTHOR]

Demonstrates the use of oscillator-amplifier system for spectral narrowing of high-power D[sub2]O laser, in which a single-mode output from a compact D[sub2]O laser with a short cavity length was amplified by a large D[sub2]O laser amplifier. Significance of the spectral narrowing of an optically pumped high-power D[sub2]O laser; Differences of D[sub2]O laser from the conventional laser system; Maximum output energy of the D[sub2]O laser system.

The article presents a research study that investigated the effectiveness of stroke volume variation (SVV) shown by the Vigileo-FloTrac system in predicting fluid responsiveness in patients undergoing airway pressure release ventilation (APRV). An overview is provided for both APRV and the Vigileo-FloTrac system. Methods are described including the automated calculation of SVV and the experimental protocol. Results are discussed indicating SVV acceptable levels of sensitivity and specificity.

Abstract: The edge plasma profile (the ion-saturation current profile) and its time evolution at three different positions of the field topology (near inboard-X, outboard-O and outboard-X points) are discussed focusing on the spontaneous transition to an improved mode in Heliotron J ECH-plasma. For all three positions it is found that the plasma profile becomes steeper as progress of the transition. In the early phase of the transition, however, the different time response is observed between the profiles near X- and O-points. [Copyright &y& Elsevier]

Abstract: In the helical-axis heliotron configuration, bumpiness of the confinement field ε b is introduced to control the plasma transport. The plasma performance were experimentally investigated in Heliotron J for three configurations with ε b =0.01, 0.06 and 0.15 at ρ =2/3. The obtained volume-averaged stored energy depends on the configuration. To understand the observed difference in global energy confinement, the ε b-control effects on the edge plasma is discussed. For ε b =0.01, the plasma density and temperature in the peripheral region is low compared to other cases. This poor plasma edge relates to the observed low stored energy or poor energy confinement for ε b =0.01. [Copyright &y& Elsevier]

Abstract: For comparative assessment of tokamak and helical reactors, two base case reactor designs with 1GW electric power output are introduced; high-field high-beta compact tokamak reactor TR-1 (major radius R =5.2m, magnetic field B =7.1T) and high-beta helical system HR-1 (R =12.1m, B =4.6T). Operational boundaries of both reactors are compared by the zero-dimensional energy balance model, which clarifies the difference between the higher temperature operational regime of TR-1 and the lower temperature regime of HR-1. These operational scenarios are reconfirmed by the toroidal transport analysis linkage (TOTAL) code coupling with two-dimensional equilibrium in the TOTAL-T tokamak code and three-dimensional equilibrium in the TOTAL-H helical code. The beta effect on confinement degradation and the impurity radiation effect on energy balance are found to make the ignition difficult in both systems. [Copyright &y& Elsevier]

Abstract: In order to investigate the velocity distribution function of deuterium atoms, which gives information about the recycling process, in the Heliotron J edge plasma region, spectral line shapes of Dα emitted in front of a carbon limiter have been measured with a high-resolution spectrometer. Measured spectral profiles have an asymmetric structure and are decomposed into the broad and narrow Gaussian components. The central wavelengths of each component shift toward the blue side. The intensity distribution is similar to the footprint of the magnetic field lines on the limiter surface. The emission from reflected atoms affects the intensity distribution of the broad component. [Copyright &y& Elsevier]

The radial electric field is driven to positive value by off-axis second harmonic electron cyclotron heating (ECH) in the Compact Helical System [Plasma Physics and Controlled Nuclear Fusion Research 1988, Nice (International Atomic Energy Agency, Vienna, 1989), Vol. II, p. 411]. The observed positive electric field is associated with the outward particle flux enhanced with ECH. The enhanced particle flux triggered by the production of the electrons accelerated perpendicularly to the magnetic field with ECH results in the change of the electric field. [ABSTRACT FROM AUTHOR]

Asserts that a reversed-field pinch (RFP) dynamo uniformly generates most of the toroidal flux in a RFP plasma with a high magnetic Reynolds number. Features of the global dynamo and magnetic fluctuations; Global dynamo and Taylor's theory; Mechanism of the global dynamo.