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31.
La(3+) and not Ca(2+) increases methanol dehydrogenase (MDH) activity in Methylobacterium radiotolerans NBRC15690. La(3+)- and Ca(2+)-MDH-like proteins were found to be homodimeric (α(2)) and heterotetrameric (α(2)β(2)), respectively. N-terminal amino acid sequences of these proteins revealed that La(3+)- and Ca(2+)-MDH-like proteins were encoded by xoxF and mxaFI, respectively.  相似文献   
32.
Kihara T 《Applied optics》2011,50(17):2582-2587
The Stokes parameters (S0, S1, S2, and S3) of monochromatic light can be measured using the adjustable azimuth settings of a quarter-wave plate and a polarizer. When measuring the Stokes parameters of light of an arbitrary wavelength, the measurement of S3 is affected by the phase difference error Δq(λi), due to the mismatch with respect to wavelength with the quarter-wave plate. In this method, Δq(λi), due to such a mismatch of incident light of arbitrary wavelength, can be overcome by a judicious choice of azimuth settings of the quarter-wave plate and the use of a polarizer; however, the use of a precision quarter-wave plate is necessary. The present paper proposes a measurement method of Stokes parameters of incident light of arbitrary wavelength using a quarter-wave plate with phase difference errors.  相似文献   
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Maru K  Fujiwara T  Ikeuchi R 《Applied optics》2011,50(32):6121-6127
A transverse scanning laser Doppler velocimeter (LDV) that does not require any moving mechanism in its sensor probe is proposed, and the scanning function is demonstrated theoretically and experimentally. In the proposed scanning LDV, the measurement position is transversely scanned on the basis of a wavelength change induced by a tunable laser and a combination of a grating and a Dove prism. To demonstrate the scanning function in the transverse direction, an experiment was carried out using a setup of the sensor probe consisting of bulk optical components. The experimental results indicate that a transverse scanning function was successfully obtained. The scanning range in the vertical direction is estimated to be 11.3 mm over wavelengths of 1520 to 1570 nm.  相似文献   
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The effect of the choice of maternal age-specific prevalence curve on the model predicted Down syndrome detection rate was examined. All 19 published regression curves from 11 birth prevalence series in four meta-analyses were included. The detection rate for a five per cent false-positive rate was estimated for three combinations of markers. For free beta human chorionic gonadotropin and alpha-fetoprotein the lowest predicted detection rate was 62.3 per cent and the highest 64.1 per cent, a range of 1.8 per cent. When unconjugated oestriol was added as a third marker it was 65.6-67.3 per cent, a 1.7 per cent range, and when inhibin A was the fourth marker the detection rate was 72.0-73.4 per cent, a 1.4 per cent range. The number of series included in the regression had the biggest effect: when the authors had used a subset thought to have the highest ascertainment the predicted detection rate generally increased. The type of regression equation used and restrictions on the age range over which the regression was performed were less important factors. The effect of the choice of curve on the predicted increase in detection achieved by incorporating additional markers was relatively small: 3.1-3.3 per cent for unconjugated oestriol and a further 6.1-6.5 per cent for inhibin A. This analysis shows that the model inaccuracy caused by the maternal age curve is not small but is unlikely to be large enough to influence Down syndrome screening policy decisions.  相似文献   
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A high-power CW 27.972 μm water-vapor laser has been developed for interferometric and polarimetric measurements of plasmas. The maximum output power and the power density in the cavity of the laser with 2.0 cm bore and 220 cm length reach 85 mW and 109 μW/cm3, respectively. An interferometer using this laser is constructed and its performance is examined as a study on polarimetric method of magnetic field measurement. Preliminary interferometric experiments are also carried out on a compact toroidal plasma with field-reversal configuration.  相似文献   
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To propose a new arterial spin labeling (ASL) perfusion-imaging method (alternate slab width inversion recovery ASL: AIRASL) that takes advantage of the qualities of 3.0 T.  相似文献   
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