Trend in the atmospheric heat source over the central and eastern Tibetan Plateau during recent decades: Comparison of observations and reanalysis data

The trend in the atmospheric heat source over the central and eastern Tibetan Plateau (CE-TP) is quantitatively estimated using historical observations at 71 meteorological stations, three reanalysis datasets from 1980-2008, and two satellite radiation datasets from 1984-2007. Results show that a weakening of sensible heat (SH) flux over the CE-TP continues. The most significant trend occurs in spring, induced mainly by decelerated surface wind speeds. The ground-air temperature difference shows a notable increasing trend over the last 5 years. Trends in net radiation flux of the atmospheric column over the CE-TP, evaluated by two satellite radiation datasets, are clearly different. Trends in the atmospheric heat source calculated by the three reanalysis datasets are not completely consistent, and even show opposite signals. Results from the two datasets both show a weakening of the heat source but the magnitude of one is significantly stronger, whereas an increase is indicated by the other data. Therefore, it is challenging to accurately calculate the trend in the atmospheric heat source over the CE-TP, particularly from the estimates of the reanalysis datasets.     

Expression profile analysis of 9 heat shock protein genes throughout the life cycle and under abiotic stress in rice

Plant heat shock proteins (Hsps) facilitate protein folding or assembly under diverse developmental and adverse environmental conditions. Nine OsHsps were identified in our previous study from a proteomic analysis of rice cv. IRAT 109 leaf samples at the seedling stage under drought stress. To obtain additional information on the 9 OsHsp genes, this study focused on an expression profile analysis at different development stages throughout the life cycle of rice, and under different abiotic stresses and phyto-hormone treatments. The 9 genes exhibited distinctive expression patterns in different organs or development stages. Five of the genes (OsHsp72.90, OsHsp72.57, OsHsp71.18, OsHsp24.15 and OsHsp18.03) showed high expression in the endosperm, indicating that OsHsp genes may play important roles in rice seed development. All 9 OsHsps were up-regulated under heat, polyethylene glycol, and abscisic acid treatment, whereas salt stress caused up-regulation of 6 genes (OsHsp93.04, OsHsp71.10, OsHsp71.18, OsHsp72.57, OsHsp24.15 and OsHsp18.03) and cold stress resulted in down-regulation of OsHsp93.04 and OsHsp72.57. These diverse expression profiles imply potential functional diversity of the Hsp gene family in rice.