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A continuous-wave cavity ring-down spectrometer with sub-MHz precision has been built using the sideband of a frequency stabilized laser as the tunable light source. The sideband is produced by passing the carrier laser beam through an electro-optic modulator (EOM) and then selected by a short etalon on resonance. The carrier laser frequency is locked to a longitude mode of a thermo-stabilized Fabry-Perot interferometer (FPI) with a long-term absolute frequency stability of 0.2 MHz (5 × 10-10). Broad and precise spectral scanning is accomplished, respectively, by selecting a different longitudinal mode of the FPI and by tuning the radio-frequency driving the EOM. The air broadened water absorption line at 12 321 cm-1 was studied to test the performance of the spectrometer. [ABSTRACT FROM AUTHOR]

Sj16, a 16-kDa protein produced by Schistosoma japonicum, has been demonstrated to have anti-inflammatory effect. However, the possible mechanism of these phenomena has not been discovered. Here, we tried to touch it with arthritis rats' model induced by injection of complete Freund's adjuvant (CFA). A set of pathogenic characters were observed in CFA-treated rat, including local and systematic read-out, which showed the model successfully set up. After administration of rSj16 (recombinant Sj16) in vivo, paw swelling reduced significantly and in a dose-dependent manner, the level of TNF-α, IL-1β and NO decreased and IL-10 in the serum increased. In vitro, rSj16 reversed the augmented surface expression of CD80, CD86, CD54 and OX6 induced by lipopolysaccharide (LPS) in bone marrow-derived DCs (BMDCs), whereas endocytotic capacity of rSj16-treated dendritic cell (DC) was profoundly increased. IL-12p70 released from rSj16-treated BMDC was decreased but IL-10 increased. Further, following incubation with rSj16 primed BMDCs, the sensitized T cells exhibited increased production of anti-inflammatory IL-10 and IL-4 and decreased production of IL-12p70 and IFN-γ. Collectively, these results implied that rSj16 alleviated CFA-induced arthritis, and the possible mechanisms may be its interruption of maturation and function of DCs. rSj16 could be a potential therapeutic agent against rheumatoid arthritis. [ABSTRACT FROM AUTHOR]

Gold as a hydrogen-sensing electrode for in situ measurement of dissolved H2 in aqueous solutions under extreme conditions is reported. The dissolved H2 sensor, constructed with a Au-based sensing element and coupled with a YSZ/HgO/Hg electrode, is well suited for determining dissolved H2 concentrations of aqueous fluids at elevated temperatures and pressures. The Au electrode is made of Au wire mounted in a quartz bar, which can be pressurized and heated in the high-pressure and -temperature conditions. The Au-YSZ sensor has been tested for its potential response to the concentrations of dissolved H2 in fluids by using a flow-through reactor at high temperatures up to 400 °C and pressures to 38 MPa. Good sensitivity and linear response between the hydrogen concentrations in the fluids and the H2 sensor potentials are reported for hydrogen gas in the concentration range of 0.1-0.001 M H2 in aqueous fluids at temperatures up to 340 °C and 30 MPa. Nernstian response of the cell potential to dissolved H2 in fluids was determined at 340 °C and 30 MPa, described as follows: ΔE =0.9444 + 0.0603 log mH2 The experimental results indicate that the Au-YSZ/HgO/Hg cell can be used to measure the solubility of H2 in aqueous fluid at temperatures and pressures near to the critical state of water. Thus, this type of Au hydrogen sensor could be easily used for in situ measurement of H2 in hydrothermal fluids in a high-pressure vessel, or at midocean ridge, due to its structure of compression resistance. [ABSTRACT FROM AUTHOR]

Melt of NaCO3 can favor oxidation of Zr to form ZrO2 thin film on Zr surface, which is used to make Zr/ZrO2 oxidation/reduction electrode of pH sensor for testing elevated temperature aqueous solutions. Using SEM, EPMA, XPS, EXAFS and HRTEM, we found that ZrO2 film is tightness and solid with 20 μm thickness composed by nanometer-sized monoclinic crystals. Zr/ZrO2 interface is characterized of zoning structure according to topography and chemical composition in five zones: oxygen-rich ZrO2, ZrO2, oxygen-rich Zr metal, oxygen-bearing Zr and Zr from outmost to center. Melt oxidation process of Zr involved oxidation time, air and temperature. The air is important effect on structural and electrochemical properties of ZrO2 thin film for making elevate temperature electrochemical sensor. If oxygen air largely presented in carbonate melting process, ZrO2 thin film is not tightness and not for oxidation/reduction electrode. [ABSTRACT FROM AUTHOR]

Using the broad band spectral index of 164 blazars in a low state, we studied the possible correlation between different broad band spectral index ( α r. ir , α r. o , α r. x , α r. γ , α ir. o , α ir. x , α ir. γ , α o. x , α o. γ , α x. γ ). We also studied the possible correlation between different broad band spectral index of high-frequency peaked Bl Lac object (HBL), low-frequency peaked BL Lac object (LBL) and flat spectral radio quasars (FSRQs), respectively. The strong anti-correlations were found between α r. o and α o. γ , between α r. o and α x. γ in a low state for our blazar sample. For LBL and FSRQs, the strong anti-correlations were found between α r. ir and α ir. x , between α r. o and α o. x , and between α r. o and α o. γ in a low state. Based on these results, we suggested that the seed photons of the γ-ray drive from both the jet and the external accretion disk or the broad-line region, and that the subclasses of blazars seem to the different emission mechanism. [ABSTRACT FROM AUTHOR]

Neutron activation analysis (NAA) and synchrotron radiation X-ray fluorescence analysis (SRXRF) were used to study the loss and recuperation of inorganic elements of osteoporotic rat bone and the effects of Zhugu Capsule. The results of the animal experiments showed that there was greater loss of multiple elements in cancellous bone than in cortical bone that was difficult to be improved. Yet in the mid-shaft femur, which is mainly consisted of cortical bone, the contents of multiple elements were notably recuperated. Zhugu Capsule could increase the content of not only of Ca, but also Zn and Sr. Further, it could also improve the distribution of these elements in femur. [ABSTRACT FROM AUTHOR]

Abstract: Fourier transform spectra of water vapor enriched in 18O and 17O were recorded between 8012 and 9336cm−1 and analyzed for the first time. High accuracy ab initio predictions of line positions and intensities by Partridge and Schwenke [J. Chem. Phys. 106 (1997) 4618–4639; 113 (2000) 6592–6597] were used in the process of spectrum assignment. Transitions involving the (031), (111), (130), (210), and (012) upper vibrational states were identified in the recorded spectra. As a result, 514 and 244 precise ro-vibrational energy levels were derived for the H2 18O and H2 17O molecules, respectively. High-order resonance perturbations between levels of the vibrational states involved were evidenced leading to the identification of a number of rotational levels of the (050) and (060) highly excited bending states. [Copyright &y& Elsevier]

Abstract: The high-resolution absorption spectrum of the HDO molecule was recorded with a Fourier-transform interferometer in the region of 8900–9600cm−1, where the strongly interacted bands 2ν1+ν3, 3ν1+ν2, ν1+2ν2+ν3, 2ν1+3ν2, 4ν2+ν3, ν1+5ν2, and 7ν2 are located. About 1000 transitions were assigned to these seven bands based on the ab initio predictions [J. Chem. Phys. 106 (1997) 4618]. Altogether, 375 upper energy levels were determined, including 24 energy levels of the highly excited bending (070) state. On that basis, the necessity of the “Effective Hamiltonian” concept in the spectroscopic analysis is discussed. [Copyright &y& Elsevier]

This paper presents a new combination of the finite-difference time-domain (FDTD) method and the least-squares support vector machines (LS-SVM) technique. The LS-SVM is a statistical-learning method which has a self-contained basis of statistical-learning theory and excellent learning performance. A short segment of an FDTD record is used to train the LS-SVM predictor in order to obtain an accurate future realization. Numerical simulations for two typical microwave filters demonstrate that the LS-SVM method can achieve good forecasting accuracy and the efficiency of the FDTD method can be improved by up to 70%. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 296–299, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20615 [ABSTRACT FROM AUTHOR]

In this paper, a low-pass filter (LPF) with a uniplanar compact electromagnetic band-gap (UC-EBG) structure in the ground plane is investigated. The finite-difference time-domain (FDTD) method combined with the modified matrix pencil (MMP) method is applied to analyze this complicated structure. A short segment of an FDTD record is used to train the MMP predictor, and an accurate future realization can be obtained. The numerical simulation for low-pass filters with UC-EBG demonstrates that the efficiency of the FDTD method can be improved by up to 70%. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 37–41, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20540 [ABSTRACT FROM AUTHOR]