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101.
Uchida T  Abe C  Nomura S  Ichikawa T  Ikeda S 《Lipids》2012,47(2):129-139
The aim of this study was to evaluate tissue distribution of vitamin E isoforms such as α- and γ-tocotrienol and γ-tocopherol and interference with their tissue accumulation by α-tocopherol. Rats were fed a diet containing a tocotrienol mixture or γ-tocopherol with or without α-tocopherol, or were administered by gavage an emulsion containing tocotrienol mixture or γ-tocopherol with or without α-tocopherol. There were high levels of α-tocotrienol in the adipose tissue and adrenal gland, γ-tocotrienol in the adipose tissue, and γ-tocopherol in the adrenal gland of rats fed tocotrienol mixture or γ-tocopherol for 7 weeks. Dietary α-tocopherol decreased the α-tocotrienol and γ-tocopherol but not γ-tocotrienol concentrations in tissues. In the oral administration study, both tocopherol and tocotrienol quickly accumulated in the adrenal gland; however, their accumulation in adipose tissue was slow. In contrast to the dietary intake, α-tocopherol, which has the highest affinity for α-tocopherol transfer protein (αTTP), inhibited uptake of γ-tocotrienol to tissues including adipose tissue after oral administration, suggesting that the affinities of tocopherol and tocotrienol for αTTP in the liver were the critical determinants of their uptake to peripheral tissues. Vitamin E deficiency for 4 weeks depleted tocopherol and tocotrienol stores in the liver but not in adipose tissue. These results indicate that dietary vitamin E slowly accumulates in adipose tissue but the levels are kept without degradation. The property of adipose tissue as vitamin E store causes adipose tissue-specific accumulation of dietary tocotrienol.  相似文献   
102.
In a quartz crystal oscillator circuit, an LC resonance circuit was inserted that enabled major enlargement of the variable range of frequency compared with the conventional Colpitts or Pierce quartz crystal oscillator. The short‐term stability of the oscillation was measured with Allan variance in the intermediate region between the quartz resonance and LC resonance, showing higher stability compared with the common LC oscillator. The analytical result is presented showing continuous transition from the quartz resonance to the LC resonance. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
103.
Using TiO2–water nanofluids as the test liquid, pool boiling experiments were carried out to investigate the dependence of the nucleate boiling heat transfer, surface wettability and critical heat flux (CHF) on the boiling time in nanofluids. In the experiments performed at sufficiently high nanoparticle concentrations, the boiling heat transfer first degraded, then improved, and finally reached an equilibrium state. It was hence supposed that the present nanofluids had competing effects to deteriorate and enhance the nucleate boiling heat transfer. As for the surface wettability and CHF, the static contact angle asymptotically decreased whilst the CHF asymptotically increased with an increase in the boiling time. The maximum CHF enhancement measured in the present experiments was 91%, and strong correlation was found between the contact angle and the CHF. Although the boiling time needed to achieve the maximum CHF enhancement was less than a minute at high particle concentrations, a longer time of the order of 1 h was necessary at the lowest particle concentration tested in this work. This experimental result indicated that sufficient attention should be paid to the boiling time effect particularly in industrial applications of nanofluids to emergency cooling.  相似文献   
104.
An analytical study using the nonlinear finite-element method was conducted for reinforced concrete shear wall tests under cyclic loading to estimate the damage from the aspect of energy consumption. First, the validity of the analytical method was confirmed by studying the load–displacement relationship, the condition of the cracking, and a comparison between the total strain energy of the analysis and the loaded energy of the test. Next, the distribution of the energy consumption was investigated, and the division between rebars and concrete was studied. It was determined that energy consumption is an effective method for estimating damage of shear walls.  相似文献   
105.
Investigations of the process of submerged-arc surfacing show that the experimental values of the thermal process of penetration of the parent metal at low values of current and surfacing speed are approximately half the values obtained in theoretical investigations. The addition of a correction to the well-known Rykalin procedure results in calculated values with an error not higher than 10% and can be used to determine the area of the penetration zone of the parent metal in submerged-arc surfacing in the surfacing current range of 400–1000 A and the surfacing speed range of 5–10 m/h.  相似文献   
106.

The identification of activity locations in continuous GPS trajectories is an essential preliminary step in obtaining person trip data and for activity-based transportation demand forecasting. In this research, a two-step methodology for identifying activity stop locations is proposed. In the first step, an improved density-based spatial clustering of applications with noise (DBSCAN) algorithm identifies stop points and moving points; then in the second step, the support vector machines (SVMs) method distinguishes activity stops from non-activity stops among the identified stop points. A time sequence constraint and a direction change constraint are applied as improvements to DBSCAN (yielding an improved algorithm known as C-DBSCAN). Then three major features are extracted for use in the SVMs method: stop duration, mean distance to the centroid of a cluster of points at a stop location, and the shorter of distances from current location to home and to the workplace. The proposed methodology was tested using GPS data collected from mobile phones in the Nagoya area of Japan. The C-DBSCAN algorithm achieves an accuracy of 90 % in identifying stop points in the first step, while the SVMs method is 96 % accurate in distinguishing the locations of activity stops from non-activity stops in the second step. Compared to other variants of DBSCAN used to identify activity locations from GPS trajectories, this two-step method is generally superior.

  相似文献   
107.
A laser beam scanning system consisting of a scanning micro-mirror and a varifocal micro-mirror is fabricated for laser beam sensing with variable beam diameter. The scanning micro-mirror is operated under the resonant oscillation condition with an electrostatic comb-drive actuator. The varifocal micro-mirror is driven by a bending moment generated at the circumference of mirror with a parallel-palate electrostatic actuator. The scanning micro-mirror and the varifocal mirror are fabricated on a silicon on insulator wafer. The rotational angle of 9° at 766 Hz is obtained at the voltage of 300 V. The spot size of the laser beam is adjusted from 0.5 to 3.5 cm at the distance of 43 m by changing varifocal voltage. The proposed scanning system can be useful for several sensing techniques.  相似文献   
108.
The timing involved in generating communicative actions and utterances in a face-to-face greeting interaction for application in robot–human and computer-generated (CG) character–human interaction support systems is analyzed by synthesis. First, an analysis of human greeting clarifies the average pause and the average time delay in the utterance to a communicative action. Then, a synthesis-based analysis is performed by using an embodied robot system. This analysis confirms that the variation in the pause and the lag in the utterance to communicative actions produce different communicative effects, for example, a lag of about 0.3 sec is desirable for a familiar greeting and a longer lag is appropriate for a polite greeting. In addition, the synthesis-based analysis performed on a CG character system confirms the timing control effects. These results demonstrate the importance of timing control in embodied interactions as well as the applicability of such interactions in advanced communications with robots and CG characters.  相似文献   
109.
The axial variation of film flow rate in annular regime was analyzed to predict the critical heat flux in water saturated flow boiling in various vertical channels. In the analyses, several quantities including the deposition and entrainment rates of droplets were evaluated with the correlations that were based on the separate experimental data of film flow rate and droplet flow rate in annular flow; model closure was achieved without introducing arbitrary constants. The predicted results were compared with extensive data of critical heat flux in flow boiling. Fairly good agreements were observed for the critical heat fluxes in round tubes with uniform and axially non-uniform heating and in non-circular shaped channels without sharp corners. It is hence expected that the important processes for the onset of critical heat flux condition in annular regime were satisfactorily described in the model. However, the critical heat fluxes were generally overestimated in thin rectangular channels with sharp corners. The non-uniform distribution of liquid film in channel cross-section would be the primary reason of the disagreement.  相似文献   
110.
New technologies to increase the photo-sensitivity and reduce the shutter voltage of the vertical over-flow-drain (VOD) have been developed for CCD image sensors. The photo-sensitivity was increased 40% by forming an anti-reflection film over the photodiode and reducing the thickness of the p+-layer formed at the photodiode surface. The VOD shutter voltage was reduced from 31 to 18 V by using an epitaxially grown substrate with double impurity concentration layers  相似文献   
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