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Marked increases in active‐layer and upper permafrost temperatures occurred in the central Lena River basin in association with abrupt increases in active‐layer soil moisture following the summer of 2005. The positive trend in soil temperature‐moisture relations was observed at monitoring sites in the Yakutsk area, regardless of vegetation and soil type. The increase in soil temperature appears to have started in response to the large amounts of snow that accumulated in the winter of 2004. Abnormally high pre‐winter rainfall and snowfall in the following three years accelerated soil warming through the effects of greater latent heat of freezing and insulation from atmospheric cooling in winter. The consecutive positive anomalies of snow depth and rainfall, which occurred widely in the central and southern Lena River basin during this three‐year period, increased soil moisture and appear to have altered the active‐layer thermal properties, which likely induced widespread warming of the surface layer of permafrost in this region. Copyright © 2009 John Wiley & Sons, Ltd.

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Hypertrophic cardiac growth is a major compensatory response of the heart to an increased mechanical (hemodynamic) load in the form of either pressure or volume overload. Although this response is initially compensatory, a transition from this state to failure occurs when further growth of the heart is not sufficient to normalize the wall stress and maintain contractile function (1). Therefore, a major research interest in cardiovascular disease is to understand how the increase in hemodynamic load is transmitted intracellularly for mediating hypertrophic growth. Although the mechanical load appears to directly regulate the hypertrophic growth initiation, the signaling mechanism that connects load to such growth is not well understood.A major cellular event during cardiac hypertrophy is increased protein synthesis (1-5). Enhanced protein synthesis can occur via accelerated protein translation, increased biogenesis of translational components, or both. A significant amount of mRNA of vertebrate cells possesses a unique 5Ј-terminal oligopyrimidine (5Ј-TOP) 1 sequence in the 5Ј-untranslated region (5Ј-UTR), and these mRNA species generally code for specific ribosomal proteins (6, 7). Their translation is largely controlled via phosphorylation of the 40 S ribosomal S6 protein (S6 protein) at its C terminus (8) by p70/85 S6 kinase (S6K1) (9 -12). There are two isoforms of S6K1: the 70-kDa isoform was first isolated from mouse 3T3 cells (13), and the 85-kDa isoform of this kinase was then identified (14). The p85 isoform is expressed from the same transcript as the p70 isoform through an alternative translational initiation start site, which adds a 23-amino acid nuclear localization signal to the N terminus (15,16). Therefore, the 85-kDa isoform is predominantly in the nucleus, whereas the 70-kDa isoform is present mostly in the cytoplasm. Both the S6K isoforms are collectively called p70/85S6K, p70S6K, or S6K1 and have been shown to phosphorylate the S6 protein and mediate the biogenesis of the translational components, including several of the ribosomal proteins and elongation factors (12). The p85 isoform has been shown to have additional roles in translational control, G 1 to S phase transition, and increased DNA synthesis (17). Recent studies using S6K1 knockout mice (18) demonstrate no appreciable change in S6 protein phosphorylation, 5Ј-TOP mRNA translation, or cell growth, although these mice exhibited a small mouse phenotype. These studies (18) and other independent studies (19 -21) resulted in the discovery of another S6K (S6K2), which possesses 70% homology with the p70 isoform of

Permafrost degradation and changes in water balance in a thermokarst lake in the middle part of the Lena River basin in eastern Siberia were investigated. We analysed the role of permafrost thawing in the water balance of a growing thermokarst lake. Long-term observations during the last two decades (1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008) at our thermokarst monitoring site, Yukechi, showed significant modifications of the landforms. Observations included ground temperature, thawing depth, soil moisture content in the active layer, surface subsidence rate, and ecological changes in the surrounding environment. We also used data obtained at the Yakutsk weather station to estimate the potential evaporation. During the observation period, the water surface area increased steadily from 195 m 2 in 1993 to 3135 m 2 in 2008, and the lake water increased from 33Á7 m 3 in 1993 to 3503 m 3 in 2008. Water balance estimations showed that ground ice melt made up to one third of the total water input into the lake. The rapid development of growing thermokarst lakes indicates an ecological risk on the edges of cryogenic landscapes. Finally, we found that climate change and anthropogenic impacts have led to enhanced activity of cryogenic processes in the region. In particular, cultivated fields underlying ice-rich permafrost face enhanced degradation by cryogenic and hydrological processes because of recent climate change in the region.