Let A be a graded C∗-algebra. We characterize Kasparov’s K-theory group K̂0(A) in terms of graded ∗-homomorphisms by proving a general converse to the functional calculus theorem for self-adjoint regular operators on graded Hilbert modules. An application to the index theory of elliptic differential operators on smooth closed manifolds and asymptotic morphisms is discussed.

Members of the Ether à go-go (Eag) K+ channel subfamilies Eag, Erg, and Elk are widely expressed in the nervous system, but their neural functions in vivo remain largely unknown. The biophysical properties of channels from the Eag and Erg subfamilies have been described, and based on their characteristic features and expression patterns, Erg channels have been associated with native currents in...

The active transport of Na’ and K + across cell membranes is catalysed by the ubiquitous transport system known as the Na+,K+-pump. Historically, Dean [ l] was the first to propose the name sodium pump for this physiological process, and in 1057 Skou discovered the enzyme, the Na+ ,K +-activated ATPase, soon shown to be identical to the transport system [2]. The structure and mechanism of Na+,K...

Let F be a separable Banach space, and let (X, Y ) be a random pair taking values in F×R. Motivated by a broad range of potential applications, we investigate rates of convergence of the k-nearest neighbor estimate rn(x) of the regression function r(x) = E[Y |X = x], based on n independent copies of the pair (X, Y ). Using compact embedding theory, we present explicit and general finite sample ...

In this paper we study a general version of regression where each covariate itself is a functional data such as distributions or functions. In real applications, however, typically we do not have direct access to such data; instead only some noisy estimates of the true covariate functions/distributions are available to us. For example, when each covariate is a distribution, then we might not be...

In image decompositions, one is interested in decomposing f into u+v where u and v have different features. In a variational approach, such a decomposition is achieved by solving the following variational problem inf (u,v)∈X1×X2 {tF1(u) + F2(v) : f = u+ v} , where F1 and F2 are positive functionals defined on some function spaces X1 and X2 respectively. Often the scale parameter t is fixed a pr...

KCNQ (Kv7) channels underlie a voltage-gated K(+) current best known for control of neuronal excitability, and its inhibition by Gq/11-coupled, muscarinic signaling. Studies have indicated expression of KCNQ channels in airway smooth muscle (ASM), a tissue that is predominantly regulated by muscarinic receptor signaling. Therefore, we investigated the function of KCNQ channels in rodent ASM and...

SliK, a K 1 channel encoded by the Streptomyces KcsA gene, was expressed, purified, and reconstituted in liposomes. A concentrative 86 Rb 1 flux assay was used to assess the ion transport properties of SliK. SliK-mediated ionic flux shows strong selectivity for K 1 over Na 1 and is inhibited by micromolar concentrations of Ba 2 1 , mirroring the basic permeation characteristic of eukaryotic K 1...

We describe a cell-based assay for studying vitamin K-cycle enzymes. A reporter protein consisting of the gla domain of factor IX (amino acids 1-46) and residues 47-420 of protein C was stably expressed in HEK293 and AV12 cells. Both cell lines secrete carboxylated reporter when fed vitamin K or vitamin K epoxide (KO). However, neither cell line carboxylated the reporter when fed KO in the pres...