Age Determination Method of Pre-Main Sequence Stars with High-Resolution I-Band Spectroscopy

We present a new method for determining the age of late-K type pre-main sequence (PMS) stars by deriving their surface gravity from high-resolution I-band spectroscopy. Since PMS stars contract as they evolve, age can be estimated from surface gravity. We used the equivalent width ratio (EWR) of nearby absorption lines to create a surface gravity diagnostic of PMS stars that is free of uncertainties due to veiling. The ratios of Fe (818.67nm and 820.49nm) and Na (818.33nm and 819.48nm) absorption lines were calculated for giants, main-sequence stars, and weak-line T Tauri stars. Effective temperatures were nearly equal across the sample. The Fe to Na EWR (Fe/Na) decreases significantly with increasing surface gravity, denoting that Fe/Na is a desirable diagnostic for deriving the surface gravity of pre-main sequence stars. The surface gravity of PMS stars with 0.8 solar mass is able to be determined with an accuracy of 0.1-0.2, which conducts the age of PMS stars within a factor of 1.5, in average.Comment: 16 pages, 5 figures, 3 tables, accepted for publication in PAS

Kuranaka Shinobu 蔵中しのぶ (dir.), Chafu maki ichi - maki hachi chūshaku 茶譜巻一～巻九注釈（継続刊行）(Notes sur le thé), livres 1 à 9, édition annotée et commentée

Chafu 茶譜 est le titre d’un ouvrage qui relève du genre littéraire appelé chasho 茶書 (livres concernant la cérémonie du thé). Ce genre inclut des textes aux contenus très variés tels que des manuels, des essais, des listes d’ustensiles, des anecdotes sur les personnalités qui se sont illustrées dans la voie du thé, des recueils, des réflexions. Chafu, sans correspondre pleinement à une de ces catégories, aborde de nombreux aspects de la cérémonie du thé : le cadre architectural (jardin et pavil..

Identification of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-inducible genes in human amniotic epithelial cells

BACKGROUND: Exposure to dioxins results in a broad range of pathophysiological disorders in human fetuses. In order to evaluate the effects of dioxins on the feto-placental tissues, we analyzed the gene expression in 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) treated primary cultures of human amniotic epithelial cells. METHODS: Human amniotic epithelial cells were dispersed by trypsin from amniotic membranes and cultured in DME/Ham's F12 medium supplemented with 10% FBS. Two weeks after plating, cells were treated with 50 nM TCDD or DMSO (control), further incubated for 48 hrs, and the gene expression was analyzed by DNA microarray technology and quantitative real-time PCR. RESULTS: Thirty eight TCDD-inducible genes, including cytochromeP4501A1 and cytochromeP4501B1, were identified. One of the remarkable profiles of the gene expression was the prominent up-regulation of interferon-inducible genes. The genes involved in the interferon gene expression and interferon signaling pathways were also up-regulated. Furthermore, the expression of genes related to collagen synthesis or degradation was enhanced by TCDD. CONCLUSION: Using DNA microarray and quantitative real-time PCR analyses, we identified TCDD-inducible genes, including interferon-inducible genes and genes related to collagen synthesis or degradation, in human amniotic epithelial cells