146 research outputs found
Incorporation rate measurements of 10Be, 230Th, 231Pa, and 239,240Pu radionuclides in manganese crust in the Pacific Ocean: A search for extraterrestrial material
高エネルギー加速器研究機構 共通基盤研究施設・放射線科学センター金沢大学大学院自然科学研究科物質情報解析金沢大学理学部In order to estimate the deposition rate of extraterrestrial material onto a manganese crust in a search for supernova debris, we analyzed the contents of 10Be, 230Th, 231Pa, and 239,240Pu in a sample of manganese crust collected from the North Pacific Ocean. On the basis of the depth profile of 10Be, the growth rate of the manganese crust was determined to be 2.3 mm Myr-1. The uptake rates of 10Be, 230Th, and 231Pa onto the manganese crust were estimated to be 0.22-0.44%, 0.11-0.73%, and 1.4-4.5%, respectively, as compared to the deposition rates onto the deep-sea sediments near the sampling station, while that for 239,240Pu was 0.14% as compared to the total inventory of seawater and sediment column. Assuming that sinking particles represent 0.11-4.5% of the uptake rates, the deposition rate of extraterrestrial material onto the manganese crust was estimated to be 2-800 μ g cm-2Myr-1 according to the uptake of 10Be onto the manganese crust. Further, our estimate is similar to the value of 9-90 μ g cm-2Myr-1 obtained using the integrated global production rate of 10Be and the deposition rate of 10Be onto the manganese crust. © The Oceanographic Society of Japan/TERRAPUB/Springer 2007
Renal Distribution of Vasohibin-1 in Patients with Chronic Kidney Disease
Experimental studies have demonstrated the involvement of angiogenesis-related factors in the progression of chronic kidney disease (CKD). There have so far been no reports investigating the distribution and clinical roles of Vasohibin-1 (VASH-1), a negative feedback regulator of angiogenesis, in CKD. We recruited 54 Japanese CKD patients and 6 patients who had normal renal tissues excised due to localized renal cell carcinoma. We evaluated the correlations between the renal expression level of VASH-1 and the clinical/histological parameters. VASH-1 was observed in renal endothelial/mesangial cells, crescentic lesions and interstitial inflammatory cells. Significant positive correlations were observed between 1) crescent formation and the number of VASH-1+ cells in the glomerulus
(r=0.48, p=0.001) or cortex (r=0.64, p<0.0001), 2) interstitial cell infiltration and the number of VASH-1+ cells in the cortex (r=0.34, p=0.02), 3) the glomerular VEGFR-2+ area and the number of VASH-1+ cells in the glomerulus (r=0.44, p=0.01) or medulla (r=0.63, p=0.01). These results suggest that the renal levels of VASH-1 may be affected by local inflammation, crescentic lesions and VEGFR-2
誘導結合プラズマ質量分析法を用いた環境水中微量有害金属元素分析
To clarify the influence of unlawfully dumped wastes in the boundary area between Aomori and Iwate prefecture,we are analyzing the trace and toxic metal elements in leached water from the field and collected water samples around the field by using inductively coupled plasma spectrometry. We collected water samples from eleven points and confirmed that the concentrations of cadmium,lead and mercury indicate below the environmental standard values. But the obtained values for arsenic and selenium in some of the samples showed the higher values affected by the coexistence materials. We therefore measured these concentrations of the two elements by another method of atomic absorption analysis and clarified that each concentration for arsenic and selenium is also lower than the environmental standard for each element
Immunohistochemistry of Vasohibin-2 in Human Kidney Disease : Implications in Impaired Glucose Tolerance and Reduced Renal Function
Several angiogenesis-related factors are known to play important roles in the pathogenesis of kidney disease. Vasohibin-2 (VASH-2) was recently reported as a novel proangiogenic factor. Although VASH-2 was demonstrated to accelerate tumor angiogenesis, its roles in non-tumor processes including renal disease have not been well elucidated yet. Here, we performed a retrospective study including an immunohistochemical analysis of human kidney biopsy specimens from 82 Japanese patients with a variety of kidney diseases, and we evaluated the correlations between the immunoreactivity of VASH-2 and the patients’ clinicopathological parameters. VASH-2 immunoreactivity was detected in varying degrees in renal tubules as well as in peritubular capillaries and vasa recta. The cortical and medullary tubule VASH-2+ scores were correlated with the presence of hypertension, and the medullary tubule VASH-2+ score was significantly correlated with the blood glucose (p=0.029, r=0.35) and hemoglobin A1c levels (p=0.0066, r=0.39). Moreover, decreased VASH-2+ scores in the vasa recta were associated with reduced renal function (p=0.0003). These results suggest that VASH-2 could play an important role in the pathogenesis of renal diseases, and that VASH-2 is closely associated with hypertension and impaired glucose tolerance
Spitzer Survey of the Large Magellanic Cloud, Surveying the Agents of a Galaxy's Evolution (SAGE) I: Overview and Initial Results
We are performing a uniform and unbiased, ~7x7 degrees imaging survey of the
Large Magellanic Cloud (LMC), using the IRAC and MIPS instruments on board the
Spitzer Space Telescope in order to survey the agents of a galaxy's evolution
(SAGE), the interstellar medium (ISM) and stars in the LMC. The detection of
diffuse ISM with column densities >1.2x10^21 H cm^-2 permits detailed studies
of dust processes in the ISM. SAGE's point source sensitivity enables a
complete census of newly formed stars with masses >3 solar masses that will
determine the current star formation rate in the LMC. SAGE's detection of
evolved stars with mass loss rates >1x10^-8 solar masses per year will quantify
the rate at which evolved stars inject mass into the ISM of the LMC. The
observing strategy includes two epochs in 2005, separated by three months, that
both mitigate instrumental artifacts and constrain source variability. The SAGE
data are non-proprietary. The data processing includes IRAC and MIPS pipelines
and a database for mining the point source catalogs, which will be released to
the community in support of Spitzer proposal cycles 4 and 5. We present initial
results on the epoch 1 data with a special focus on the N79 and N83 region. The
SAGE epoch 1 point source catalog has ~4 million sources. The point source
counts are highest for the IRAC 3.6 microns band and decrease dramatically
towards longer wavelengths consistent with the fact that stars dominate the
point source catalogs and that the dusty objects, e.g. young stellar objects
and dusty evolved stars that detected at the longer wavelengths, are rare in
comparison. We outline a strategy for identifying foreground MW stars, that may
comprise as much as 18% of the source list, and background galaxies, that may
comprise ~12% of the source list.Comment: Accepted by the Astronomical Journa
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