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Karst landscape, covers more than 10% of the global land surface and plays an important role in supporting ecosystems and human society, may be strongly influenced by climate change. Vegetation available water (VAW) is a key variable impacting the sensitivity of ecosystems to a changing environment. However, VAW in karst region is difficult to determine and remains uncertain. This study improved a dynamic Budyko-type water balance model, by introducing a nonlinear equation linking climate, vegetation and Budyko-type water balance. This model was calibrated using evolutionary algorithm based on monthly runoff. Comparison results in the Pearl, Yangtze and 12 karst catchments in south China, suggested high effectiveness of this improved model in simulating monthly runoff and evapotranspiration. Furthermore, in the 12 karst catchments, the max VAW was negatively correlated to the portion of karst landscape of the catchment (POK, r=-0.63,α=0.027) and the elasticity of evapotranspiration to precipitation (r=-0.60,α=0.04). These implied that karst catchments with higher POK had lower VAW, making the ecosystems rely more on precipitation. [ABSTRACT FROM AUTHOR]

Inhibitor of nuclear factor kappa-B kinase subunit beta (IKK β ) is one of important kinases in inflammation to phosphorylate inhibitor of nuclear factor kappa-B (I κ B α ) and then activate nuclear factor kappa-B (NF- κ B). Inhibition of IKK β has been a therapeutic strategy for inflammatory and autoimmune diseases. Here we report that IKK β is constitutively activated in healthy donors and healthy Ikkβ C46A (cysteine 46 mutated to alanine) knock-in mice although they possess intensive IKK β -I κ B α -NF- κ B signaling activation. These indicate that IKK β activation probably plays homeostatic role instead of causing inflammation. Compared to Ikkβ WT littermates, lipopolysaccharides (LPS) could induce high mortality rate in Ikkβ C46A mice which is correlated to breaking the homeostasis by intensively activating p-I κ B α -NF- κ B signaling and inhibiting phosphorylation of 5' adenosine monophosphate-activated protein kinase (p-AMPK) expression. We then demonstrated that IKK β kinase domain (KD) phosphorylates AMPK α 1 via interacting with residues Thr183, Ser184, and Thr388, while IKK β helix-loop-helix motifs is essential to phosphorylate I κ B α according to the previous reports. Kinase assay further demonstrated that IKK β simultaneously catalyzes phosphorylation of AMPK and I κ B α to mediate homeostasis. Accordingly, activation of AMPK rather than inhibition of IKK β could substantially rescue LPS-induced mortality in Ikkβ C46A mice by rebuilding the homeostasis. We conclude that IKK β activates AMPK to restrict inflammation and IKK β mediates homeostatic function in inflammation via competitively phosphorylating AMPK and I κ B α ., (© 2022 Chinese Pharmaceutical Association and Institute of Materia Medica, Chinese Academy of Medical Sciences. Production and hosting by Elsevier B.V.)