42 research outputs found
Mixed expansion formula for the rectangular Schur functions and the affine Lie algebra A_1^(1)
Formulas are obtained that express the Schur S-functions indexed by Young
diagrams of rectangular shape as linear combinations of "mixed" products of
Schur's S- and Q-functions. The proof is achieved by using representations of
the affine Lie algebra of type A_1^{(1)}. A realization of the basic
representation that is of ``D_2^{(2)}''-type plays the central role.Comment: 21page
Mixed expansion formula for the rectangular Schur functions and the affine Lie algebra A(1)((1))
Formulas are obtained that express the Schur S-functions indexed by Young diagrams of rectangular shape as linear combinations of "mixed" products of Schur's S- and Q-functions. The proof is achieved by using representations of the affine Lie algebra of type A(1)((1)). A realization of the basic representation that is of "D-2((2))"-type plays the central role
Compound basis arising from the basic -module
A new basis for the polynomial ring of infinitely many variables is
constructed which consists of products of Schur functions and Q-functions. The
transition matrix from the natural Schur function basis is investigated.Comment: 12 page
Heme-dependent autophosphorylation of a heme sensor kinase, ChrS, from Corynebacterium diphtheriae reconstituted in proteoliposomes
AbstractCorynebacterium diphteriae employs the response regulator, ChrA, and the sensor kinase, ChrS, of a two-component signal transduction system to utilize host heme iron. Although ChrS is predicted to encode a heme sensor, the sensing mechanism remains to be characterized. In this report, ChrS expressed in Eshcherichia coli membranes was solubilized and purified using decylmaltoside. ChrS protein incorporated into proteoliposomes catalyzed heme-dependent autophosphorylation by ATP. Other metalloporphyrins and iron did not stimulate kinase activity. The UV–Vis spectrum of hemin in the ChrS–proteoliposomes indicated that heme directly interacts with ChrS. This is the first functional reconstitution of a bacterial heme-sensing protein
Spectropolarimetric Evidence for Radiatively Inefficient Accretion in an Optically Dull Active Galaxy
We present Subaru/FOCAS spectropolarimetry of two active galaxies in the
Cosmic Evolution Survey. These objects were selected to be optically dull, with
the bright X-ray emission of an AGN but missing optical emission lines in our
previous spectroscopy. Our new observations show that one target has very weak
emission lines consistent with an optically dull AGN, while the other object
has strong emission lines typical of a host-diluted Type 2 Seyfert galaxy. In
neither source do we observe polarized emission lines, with 3-sigma upper
limits of P_BLR < 2%. This means that the missing broad emission lines (and
weaker narrow emission lines) are not due to simple anisotropic obscuration,
e.g., by the canonical AGN torus. The weak-lined optically dull AGN exhibits a
blue polarized continuum with P = 0.78 +/- 0.07% at 4400 A < lambda_rest < 7200
A (P = 1.37 +/- 0.16% at 4400 A < lambda_rest < 5050 A). The wavelength
dependence of this polarized flux is similar to that of an unobscured AGN
continuum and represents the intrinsic AGN emission, either as synchrotron
emission or the outer part of an accretion disk reflected by a clumpy dust
scatterer. Because this intrinsic AGN emission lacks emission lines, this
source is likely to have a radiatively inefficient accretion flow.Comment: Accepted to ApJ. 6 pages, 2 figure