A new technique is proposed to solve the blind source separation (BSS) given only a single channel observation. The basis functions and the density of the coefficients of source signals learned by ICA are used as the ...A new technique is proposed to solve the blind source separation (BSS) given only a single channel observation. The basis functions and the density of the coefficients of source signals learned by ICA are used as the prior knowledge. Based on the learned prior information the learning rules of single channel BSS are presented by maximizing the joint log likelihood of the mixed sources to obtain source signals from single observation, in which the posterior density of the given measurements is maximized. The experimental results exhibit a successful separation performance for mixtures of speech and music signals.展开更多
Transforming growth factor-β （TGF-β） binds with two transmembrane serine/threonine kinase receptors, type Ⅱ （TβRII） and type Ⅰ receptors （TβRⅠ）, and one accessory receptor, type Ⅲ receptor （TβRⅢ）, to...Transforming growth factor-β （TGF-β） binds with two transmembrane serine/threonine kinase receptors, type Ⅱ （TβRII） and type Ⅰ receptors （TβRⅠ）, and one accessory receptor, type Ⅲ receptor （TβRⅢ）, to transduce signals across cell membranes. Previous biochemical studies suggested that TβRI and TβRIII are preexisted homo-dimers. Using single-molecule microscopy to image green fluorescent protein-labeled membrane proteins, for the first time we have demonstrated that TβRI and TβRⅢ could exist as monomers at a low expression level. Upon TGF-β1 stimu- lation, TβRI follows the general ligand-induced receptor dimerization model for activation, but this process is TβRⅡ- dependent. The monomeric status of the non-kinase receptor TβRⅢ is unchanged in the presence of TGF-β1. With the increase of receptor expression, both TβRI and TβRIII can be assembled into dimers on cell surfaces.展开更多
基金Sponsored by the Research Foundation of Shanghai Municipal Education Commission(Grant No06FZ012 and 06FZ028)
文摘A new technique is proposed to solve the blind source separation (BSS) given only a single channel observation. The basis functions and the density of the coefficients of source signals learned by ICA are used as the prior knowledge. Based on the learned prior information the learning rules of single channel BSS are presented by maximizing the joint log likelihood of the mixed sources to obtain source signals from single observation, in which the posterior density of the given measurements is maximized. The experimental results exhibit a successful separation performance for mixtures of speech and music signals.
基金This work was supported by the National Natural Science Foundation of China （90713024, 20821003, 30921004）, the National Basic Research Program of China （2007CB935601, 2010CB833706） and the Chinese Academy of Sciences.
文摘Transforming growth factor-β （TGF-β） binds with two transmembrane serine/threonine kinase receptors, type Ⅱ （TβRII） and type Ⅰ receptors （TβRⅠ）, and one accessory receptor, type Ⅲ receptor （TβRⅢ）, to transduce signals across cell membranes. Previous biochemical studies suggested that TβRI and TβRIII are preexisted homo-dimers. Using single-molecule microscopy to image green fluorescent protein-labeled membrane proteins, for the first time we have demonstrated that TβRI and TβRⅢ could exist as monomers at a low expression level. Upon TGF-β1 stimu- lation, TβRI follows the general ligand-induced receptor dimerization model for activation, but this process is TβRⅡ- dependent. The monomeric status of the non-kinase receptor TβRⅢ is unchanged in the presence of TGF-β1. With the increase of receptor expression, both TβRI and TβRIII can be assembled into dimers on cell surfaces.
