3,852 research outputs found
Perturbations in the Kerr-Newman Dilatonic Black Hole Background: I. Maxwell waves
In this paper we analyze the perturbations of the Kerr-Newman dilatonic black
hole background. For this purpose we perform a double expansion in both the
background electric charge and the wave parameters of the relevant quantities
in the Newman-Penrose formalism. We then display the gravitational, dilatonic
and electromagnetic equations, which reproduce the static solution (at zero
order in the wave parameter) and the corresponding wave equations in the Kerr
background (at first order in the wave parameter and zero order in the electric
charge). At higher orders in the electric charge one encounters corrections to
the propagations of waves induced by the presence of a non-vanishing dilaton.
An explicit computation is carried out for the electromagnetic waves up to the
asymptotic form of the Maxwell field perturbations produced by the interaction
with dilatonic waves. A simple physical model is proposed which could make
these perturbations relevant to the detection of radiation coming from the
region of space near a black hole.Comment: RevTeX, 36 pages in preprint style, 1 figure posted as a separate PS
file, submitted to Phys. Rev.
Smooth perturbations of the functional calculus and applications to Riemannian geometry on spaces of metrics
We show for a certain class of operators and holomorphic functions
that the functional calculus is holomorphic. Using this result
we are able to prove that fractional Laplacians depend real
analytically on the metric in suitable Sobolev topologies. As an
application we obtain local well-posedness of the geodesic equation for
fractional Sobolev metrics on the space of all Riemannian metrics.Comment: 31 page
Statistical mechanics of Kerr-Newman dilaton black holes and the bootstrap condition
The Bekenstein-Hawking ``entropy'' of a Kerr-Newman dilaton black hole is
computed in a perturbative expansion in the charge-to-mass ratio. The most
probable configuration for a gas of such black holes is analyzed in the
microcanonical formalism and it is argued that it does not satisfy the
equipartition principle but a bootstrap condition. It is also suggested that
the present results are further support for an interpretation of black holes as
excitations of extended objects.Comment: RevTeX, 5 pages, 2 PS figures included (requires epsf), submitted to
Phys. Rev. Let
CD163 expression in leukemia cutis
Background: Proper diagnosis of myeloid leukemia cutis (LC) is of great clinical importance but can be difficult because no single immunohistochemical marker is adequately sensitive or specific for definitive diagnosis. Thus, a broader panel of markers is often desirable. CD163 is highly specific for normal and neoplastic cells of the monocyte/histiocyte lineage. In this study, we examined the value of CD163 in the diagnosis of acute myeloid LC. Methods: A total of 34 cases, including 18 cases of myelomonocytic or monocytic LC, 10 cases of myeloid LC without monocytic component and 6 cases of acute lymphoblastic leukemia/lymphoma (ALL), were stained with CD163. Results: CD163 was expressed in 8 of 18 (44%) of myelomonocytic or monocytic LC and 1 of 10 (10%) of other myeloid LC, but in none of the ALL cases (0/6). CD163 was highly specific (90%) for myeloid LC with a monocytic component, but showed low sensitivity in the diagnosis of both myeloid LC in general (24%) and myeloid LC with a monocytic component (44%). Conclusions: Our results suggest that CD163 has utility as a specific marker for myeloid LC in conjunction with currently used immunohistochemical stains, but should not be used alone for diagnosis.Harms PW, Bandarchi B, Ma L. CD163 expression in leukemia cutis.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78608/1/j.1600-0560.2010.01533.x.pd
Curvature weighted metrics on shape space of hypersurfaces in -space
Let be a compact connected oriented dimensional manifold without
boundary. In this work, shape space is the orbifold of unparametrized
immersions from to . The results of \cite{Michor118}, where
mean curvature weighted metrics were studied, suggest incorporating Gau{\ss}
curvature weights in the definition of the metric. This leads us to study
metrics on shape space that are induced by metrics on the space of immersions
of the form G_f(h,k) = \int_{M} \Phi . \bar g(h, k) \vol(f^*\bar{g}). Here
f \in \Imm(M,\R^n) is an immersion of into and are tangent vectors at . is the standard
metric on , is the induced metric on ,
\vol(f^*\bar g) is the induced volume density and is a suitable smooth
function depending on the mean curvature and Gau{\ss} curvature. For these
metrics we compute the geodesic equations both on the space of immersions and
on shape space and the conserved momenta arising from the obvious symmetries.
Numerical experiments illustrate the behavior of these metrics.Comment: 12 pages 3 figure
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