1,997 research outputs found

    A Spectral Line Survey from 138.3 to 150.7 GHZ toward Orion-KL

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    We present the results of a spectral line survey from 138.3 to 150.7 GHz toward Orion-KL. The observations were made using the 14 m radio telescope of Taeduk Radio Astronomy Observatory. Typical system temperatures were between 500 and 700 K, with the sensitivity between 0.020.060.02 - 0.06 K in units of TA\rm T_A^*. A total of 149 line spectra are detected in this survey. Fifty lines have been previously reported, however we find 99 new detections. Among these new lines, 32 are `unidentified', while 67 are from molecular transitions with known identifications. There is no detection of H or He recombination lines. The identified spectra are from a total of 16 molecular species and their isotopic variants. In the range from 138.3 to 150.7 GHz, the strongest spectral line is the J=3-2 transition of CS molecule, followed by transitions of the H2CO\rm H_2CO, CH3OH\rm CH_3OH, CH3CN\rm CH_3CN, and SO2\rm SO_2. Spectral lines from the large organic molecules such as CH3OH\rm CH_3OH, CH3OCH3\rm CH_3OCH_3, HCOOCH3\rm HCOOCH_3, C2H5CN\rm C_2H_5CN and CH3CN\rm CH_3CN are prominent; with 80 % of the identified lines arising from transitions of these molecules. The rotational temperatures and column densities are derived using the standard rotation diagram analysis for CH3OH\rm CH_3OH (13CH3OH\rm ^{13}CH_3OH), HCOOCH3\rm HCOOCH_3, CH3CN\rm CH_3CN and SO2\rm SO_2 with 10270K\rm 10\sim 270 K and 0.220×1015cm2\rm 0.2\sim 20\times 10^{15} cm^{-2}. These estimates are fairly comparable to the values for the same molecule in other frequency regions by other studies.Comment: 10 figures, 2 tex files for a manuscript and tables, accepted to Ap

    Thermal surface free energy and stress of iron OPEN

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    Absolute values of surface energy and surface stress of solids are hardly accessible by experiment. Here, we investigate the temperature dependence of both parameters for the (001) and (110) surface facets of body-centered cubic Fe from first-principles modeling taking into account vibrational, electronic, and magnetic degrees of freedom. The monotonic decrease of the surface energies of both facets with increasing temperature is mostly due to lattice vibrations and magnetic disorder. The surface stresses exhibit nonmonotonic behaviors resulting in a strongly temperature dependent excess surface stress and surface stress anisotropy. Introduced by Gibbs, the surface free energy (γ) and the surface stress (σ), are the two essential macroscopic parameters that characterize the thermodynamic properties of crystalline surface

    Expression of Matrix Metalloproteinases and Their Inhibitors in Squamous Cell Carcinoma of the Tonsil and Their Clinical Significance

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    ObjectivesTo investigate expressions of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in squamous cell carcinoma of the tonsil and to correlate expression profiles with clinicopathological characteristics.MethodsParaffin blocks were obtained from 45 tonsil squamous cell carcinoma (SCC) patients, who underwent surgery as an initial treatment between 1994 and 2004, and from 20 normal controls. Expressions of MMP-2, MMP-9, MMP-13, TIMP-1, and TIMP-2 were investigated immunohistochemically.ResultsThe expressions of MMPs (except MMP-2) and TIMPs were found to be significantly different in tonsil SCC and normal control tissues. Furthermore, MMP-13 expression was found to be correlated with tumor invasion (P=0.05), and the expressions of MMP-9 and TIMP-1 with nodal metastasis (P=0.048, 0.031). No relation was found between MMP or TIMP expression and recurrence. However, MMP-9 expression was found to be significantly associated with 5-year survival in tonsil SCC patients by multivariate analysis (hazard ratio, 3.853; P=0.013).ConclusionSignificant overexpressions of multiple MMPs and TIMPs were found in tonsil SCC tissues. Furthermore, our findings suggest that MMP-9 expression might be a useful prognostic factor

    Resolution of Recalcitrant Uveitic Optic Disc Edema Following Administration of Methotrexate: Two Case Reports

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    A 13-year-old male and a 15-year-old female presented with optic disc edema associated with chronic recurrent uveitis. While the ocular inflammation responded to high doses of oral prednisolone, the disc edema showed little improvement. After oral administration of methotrexate, the disc edema and ocular inflammation were resolved, and the dose of oral corticosteroid could be reduced
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