1,375 research outputs found
IUPUI Center for Health Geographics
poster abstractThe IUPUI Center for Health Geographics develops and supports research innovation through integration of geographic information science, medical informatics, community informatics, and public health. Our areas of research emphasis include geospatial technologies and standards for health surveillance, spatial and temporal contexts of health behaviors and health outcomes, and space-time models for investigating disease and mortality trends. Our poster highlights our collaborations, which include interdisciplinary partnerships with investigators in the fields of geographic information science, social science, clinical epidemiology, medical informatics, and health services research
Successful salvage therapy of Fusarium endophthalmitis secondary to keratitis: an interventional case series
Grant M Comer, Maxwell S Stem, Stephen J SaxeUniversity of Michigan, Department of Ophthalmology and Visual Sciences, Ann Arbor, MI, USAPurpose: To describe a combination of treatment modalities used for the successful eradication of Fusarium endophthalmitis.Design: Interventional case series.Participants: Three consecutive patients with keratitis-associated Fusarium endophthalmitis.Methods: After failure of traditional management options, a combination of intravitreal and long-term, high-dose systemic voriconazole, topical antifungal medications, and surgical intervention, with penetrating keratoplasty, lensectomy, and endoscopic-guided pars plana vitrectomy, was administered to each patient.Results: All three cases achieved full resolution of the infection, with a final Snellen visual acuity score of 20/50 to 20/70.Conclusions: An aggressive combination of therapeutic modalities, including the removal of subiris abscesses, might be needed for the successful resolution of Fusarium endophthalmitis.Keywords: endophthalmitis, fungal, Fusarium, keratitis, keratoplasty, voriconazole&nbsp
Tensor mass and particle number peak at the same location in the scalar-tensor gravity boson star models - an analytical proof
Recently in boson star models in framework of Brans-Dicke theory, three
possible definitions of mass have been identified, all identical in general
relativity, but different in scalar-tensor theories of gravity.It has been
conjectured that it's the tensor mass which peaks, as a function of the central
density, at the same location where the particle number takes its maximum.This
is a very important property which is crucial for stability analysis via
catastrophe theory. This conjecture has received some numerical support. Here
we give an analytical proof of the conjecture in framework of the generalized
scalar-tensor theory of gravity, confirming in this way the numerical
calculations.Comment: 9 pages, latex, no figers, some typos corrected, reference adde
Stretching and unzipping nucleic acid hairpins using a synthetic nanopore
We have explored the electromechanical properties of DNA by using an electric field to force single hairpin molecules to translocate through a synthetic pore in a silicon nitride membrane. We observe a threshold voltage for translocation of the hairpin through the pore that depends sensitively on the diameter and the secondary structure of the DNA. The threshold for a diameter 1.5 < d < 2.3 nm is V > 1.5 V, which corresponds to the force required to stretch the stem of the hairpin, according to molecular dynamics simulations. On the other hand, for 1.0 < d < 1.5 nm, the threshold voltage collapses to V < 0.5 V because the stem unzips with a lower force than required for stretching. The data indicate that a synthetic nanopore can be used like a molecular gate to discriminate between the secondary structures in DNA
Parallel Writing on Zirconium Nitride Thin Films by Local Oxidation Nanolithography
Parallel pattern transfer of submicrometer-scale oxide features onto zirconium nitride thin films is reported. The oxidation reaction was verified by Auger microprobe analysis and secondary ion mass spectrometry. Oxide features of similar to70 nm in height can be formed and selectively etched in a dilute aqueous hydrogen fluoride solution. This provides an interesting route to potential new applications for high-melting point, biocompatible surfaces that possess small feature sizes with controlled geometries. (C) 2004 American Institute of Physics
Unconstrained Hamiltonian formulation of General Relativity with thermo-elastic sources
A new formulation of the Hamiltonian dynamics of the gravitational field
interacting with(non-dissipative) thermo-elastic matter is discussed. It is
based on a gauge condition which allows us to encode the six degrees of freedom
of the ``gravity + matter''-system (two gravitational and four
thermo-mechanical ones), together with their conjugate momenta, in the
Riemannian metric q_{ij} and its conjugate ADM momentum P^{ij}. These variables
are not subject to constraints. We prove that the Hamiltonian of this system is
equal to the total matter entropy. It generates uniquely the dynamics once
expressed as a function of the canonical variables. Any function U obtained in
this way must fulfil a system of three, first order, partial differential
equations of the Hamilton-Jacobi type in the variables (q_{ij},P^{ij}). These
equations are universal and do not depend upon the properties of the material:
its equation of state enters only as a boundary condition. The well posedness
of this problem is proved. Finally, we prove that for vanishing matter density,
the value of U goes to infinity almost everywhere and remains bounded only on
the vacuum constraints. Therefore the constrained, vacuum Hamiltonian (zero on
constraints and infinity elsewhere) can be obtained as the limit of a ``deep
potential well'' corresponding to non-vanishing matter. This unconstrained
description of Hamiltonian General Relativity can be useful in numerical
calculations as well as in the canonical approach to Quantum Gravity.Comment: 29 pages, TeX forma
r-modes in Relativistic Superfluid Stars
We discuss the modal properties of the -modes of relativistic superfluid
neutron stars, taking account of the entrainment effects between superfluids.
In this paper, the neutron stars are assumed to be filled with neutron and
proton superfluids and the strength of the entrainment effects between the
superfluids are represented by a single parameter . We find that the
basic properties of the -modes in a relativistic superfluid star are very
similar to those found for a Newtonian superfluid star. The -modes of a
relativistic superfluid star are split into two families, ordinary fluid-like
-modes (-mode) and superfluid-like -modes (-mode). The two
superfluids counter-move for the -modes, while they co-move for the
-modes. For the -modes, the quantity is
almost independent of the entrainment parameter , where and
are the azimuthal wave number and the oscillation frequency observed by an
inertial observer at spatial infinity, respectively. For the -modes, on
the other hand, almost linearly increases with increasing . It
is also found that the radiation driven instability due to the -modes is
much weaker than that of the -modes because the matter current associated
with the axial parity perturbations almost completely vanishes.Comment: 14 pages, 4 figures. To appear in Physical Review
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