4,300 research outputs found
Mining the ESO WFI and INT WFC archives for known Near Earth Asteroids. Mega-Precovery software
The ESO/MPG WFI and the INT WFC wide field archives comprising 330,000 images
were mined to search for serendipitous encounters of known Near Earth Asteroids
(NEAs) and Potentially Hazardous Asteroids (PHAs). A total of 152 asteroids (44
PHAs and 108 other NEAs) were identified using the PRECOVERY software, their
astrometry being measured on 761 images and sent to the Minor Planet Centre.
Both recoveries and precoveries were reported, including prolonged orbital arcs
for 18 precovered objects and 10 recoveries. We analyze all new opposition data
by comparing the orbits fitted before and after including our contributions. We
conclude the paper presenting Mega-Precovery, a new online service focused on
data mining of many instrument archives simultaneously for one or a few given
asteroids. A total of 28 instrument archives have been made available for
mining using this tool, adding together about 2.5 million images forming the
Mega-Archive.Comment: Accepted for publication in Astronomische Nachrichten (Sep 2012
Surgical Management of Gynecomastia—a 10-year Analysis
Background: Gynecomastia is defined as the benign enlargement of the male breast. Most studies on surgical treatment of gynecomastia show only small series and lack histopathology results. The aim of this study was to analyze the surgical approach in the treatment of gynecomastia and the related outcome over a 10-year period. Patients and methods: All patients undergoing surgical gynecomastia corrections in our department between 1996 and 2006 were included for retrospective evaluation. The data were analyzed for etiology, stage of gynecomastia, surgical technique, complications, risk factors, and histological results. Results: A total of 100 patients with 160 operations were included. Techniques included subcutaneous mastectomy alone or with additional hand-assisted liposuction, isolated liposuction, and formal breast reduction. Atypical histological findings were found in 3% of the patients (spindle-cell hemangioendothelioma, papilloma). The surgical revision rate among all patients was 7%. Body mass index and a weight of the resected specimen higher than 40 g were identified as significant risk factors for complications (p < 0.05). Conclusions: The treatment of gynecomastia requires an individualized approach. Caution must be taken in performing large resections, which are associated with increased complication rates. Histological tissue analysis should be routinely performed in all true gynecomastia corrections, because histological results may reveal atypical cellular patholog
Thomas-Fermi Calculations of Atoms and Matter in Magnetic Neutron Stars II: Finite Temperature Effects
We present numerical calculations of the equation of state for dense matter
in high magnetic fields, using a temperature dependent Thomas-Fermi theory with
a magnetic field that takes all Landau levels into account. Free energies for
atoms and matter are also calculated as well as profiles of the electron
density as a function of distance from the atomic nucleus for representative
values of the magnetic field strength, total matter density, and temperature.
The Landau shell structure, which is so prominent in cold dense matter in high
magnetic fields, is still clearly present at finite temperature as long as it
is less than approximately one tenth of the cyclotron energy. This structure is
reflected in an oscillatory behaviour of the equation of state and other
thermodynamic properties of dense matter and hence also in profiles of the
density and pressure as functions of depth in the surface layers of magnetic
neutron stars. These oscillations are completely smoothed out by thermal
effects at temperatures of the order of the cyclotron energy or higher.Comment: 37 pages, 17 figures included, submitted to Ap
Single-particle Green's functions of the Calogero-Sutherland model at couplings \lambda = 1/2, 1, and 2
At coupling strengths lambda = 1/2, 1, or 2, the Calogero-Sutherland model
(CSM) is related to Brownian motion in a Wigner-Dyson random matrix ensemble
with orthogonal, unitary, or symplectic symmetry. Using this relation in
conjunction with superanalytic techniques developed in mesoscopic conductor
physics, we derive an exact integral representation for the CSM two-particle
Green's function in the thermodynamic limit. Simple closed expressions for the
single-particle Green's functions are extracted by separation of points. For
the advanced part, where a particle is added to the ground state and later
removed, a sum of two contributions is found: the expected one with just one
particle excitation present, plus an extra term arising from fractionalization
of the single particle into a number of elementary particle and hole
excitations.Comment: 19 REVTeX page
Unstable states in QED of strong magnetic fields
We question the use of stable asymptotic scattering states in QED of strong
magnetic fields. To correctly describe excited Landau states and photons above
the pair creation threshold the asymptotic fields are chosen as generalized
Licht fields. In this way the off-shell behavior of unstable particles is
automatically taken into account, and the resonant divergences that occur in
scattering cross sections in the presence of a strong external magnetic field
are avoided. While in a limiting case the conventional electron propagator with
Breit-Wigner form is obtained, in this formalism it is also possible to
calculate -matrix elements with external unstable particles.Comment: Revtex, 7 pages. To appear in Phys. Rev. D53(2
Influence of cardiac motion on porcine AV node for the non-invasive treatment of atrial fibrillation with a scanned carbon ion beam
Schur functions and their realizations in the slice hyperholomorphic setting
we start the study of Schur analysis in the quaternionic setting using the
theory of slice hyperholomorphic functions. The novelty of our approach is that
slice hyperholomorphic functions allows to write realizations in terms of a
suitable resolvent, the so called S-resolvent operator and to extend several
results that hold in the complex case to the quaternionic case. We discuss
reproducing kernels, positive definite functions in this setting and we show
how they can be obtained in our setting using the extension operator and the
slice regular product. We define Schur multipliers, and find their co-isometric
realization in terms of the associated de Branges-Rovnyak space
Influence of cardiac motion on pulmonary veins for the non-invasive treatment of atrial fibrillation with a scanned cabon ion beam
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