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Evaluation of automated segmentation of hip joint in revision arthroplasty
We present a case of a 72-year-old female patient with a history of degenerative hip joint disease for whom a custom-made prosthesis—an acetabulum cage—was designed. With the growing number of total hip arthroplasty (THA) operations and the rapid development of technology, biology, and tissue bioengineering, there is a market to develop new artificial hip joints. The quality of the custom made prosthesis depends on the quality of segmentation to delineate accurately patient’s anatomy. The error of segmentation may propagate to the overall error of the final prosthesis. We evaluate an in-house segmentation method, that was used in the design of the custom made prosthesis, and a commercial segmentation method, using qualitative and quantitative approaches
The low-lying quadrupole collective excitations of Ru and Pd isotopes
Quadrupole excitations of even-even Ru and Pd isotopes are described within
microscopic approach based on the general collective Bohr model which includes
the effect of coupling with the pairing vibrations. The excitation energies and
E2 transition probabilities observed in 104-114Ru and 106-110Pd are reproduced
in the frame of the calculation containing no free parameters.Comment: 11 pages, 18 figures in EPS forma
Tetrahedral and Triangular Deformations of Nuclei in Mass Region
We study static non-axial octupole deformations in proton-rich nuclei,
Ge, Se, Kr, Sr, Zr and Mo, by using
the Skyrme Hartree-Fock plus BCS calculation with no restrictions on the
nuclear shape. The calculation predicts that the oblate ground state in
Se is extremely soft for the triangular deformation, and that
in Zr the low-lying local minimum state coexisting with the prolate
ground state has the tetrahedral deformation.Comment: 8 pages, 4 Postscript figures, REVTE
Microscopic Structure of High-Spin Vibrational Excitations in Superdeformed 190,192,194Hg
Microscopic RPA calculations based on the cranked shell model are performed
to investigate the quadrupole and octupole correlations for excited
superdeformed bands in 190Hg, 192Hg, and 194Hg. The K=2 octupole vibrations are
predicted to be the lowest excitation modes at zero rotational frequency. At
finite frequency, however, the interplay between rotation and vibrations
produces different effects depending on neutron number: The lowest octupole
phonon is rotationally aligned in 190Hg, is crossed by the aligned
two-quasiparticle bands in 192Hg, and retains the K=2 octupole vibrational
character up to the highest frequency in 194Hg. The gamma vibrations are
predicted to be higher in energy and less collective than the octupole
vibrations. From a comparison with the experimental dynamic moments of inertia,
a new interpretation of the observed excited bands invoking the K=2 octupole
vibrations is proposed, which suggests those octupole vibrations may be
prevalent in SD Hg nuclei.Comment: 22 pages, REVTeX, 12 postscript figures are available on reques
Coordinate-space solution of the Skyrme-Hartree-Fock-Bogolyubov equations within spherical symmetry. The program HFBRAD (v1.0)
We describe the first version (v1.00) of the code HFBRAD which solves the
Skyrme-Hartree-Fock or Skyrme-Hartree-Fock-Bogolyubov equations in the
coordinate representation within the spherical symmetry. A realistic
representation of the quasiparticle wave functions on the space lattice allows
for performing calculations up to the particle drip lines. Zero-range
density-dependent interactions are used in the pairing channel. The pairing
energy is calculated by either using a cut-off energy in the quasiparticle
spectrum or the regularization scheme proposed by A. Bulgac and Y. Yu.Comment: 39 pages, 9 figure
Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary, Annual Report 2009
This report describes the 2009 research conducted under the U.S. Army Corps of Engineers (USACE or Corps) project EST-09-P-01, titled “Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary.” The research was conducted by the Pacific Northwest National Laboratory, Marine Science Laboratory and Hydrology Group, in partnership with the University of Washington, School of Aquatic and Fishery Sciences, Columbia Basin Research, and Earl Dawley (NOAA Fisheries, retired). This Columbia River Fish Mitigation Program project, referred to as “Salmonid Benefits,” was started in FY 2009 to evaluate the state-of-the science regarding the ability to quantify the benefits to listed salmonids1 of habitat restoration actions in the lower Columbia River and estuary
Tri-axial Octupole Deformations and Shell Structure
Manifestations of pronounced shell effects are discovered when adding
nonaxial octupole deformations to a harmonic oscillator model. The degeneracies
of the quantum spectra are in a good agreement with the corresponding main
periodic orbits and winding number ratios which are found by classical
analysis.Comment: 10 pages, Latex, 4 postscript figures, to appear in JETP Letter
Evidence of Electromagnetic Absorption by Collective Modes in the Heavy Fermion Superconductor UBe13
We present results of a microwave surface impedance study of the heavy
fermion superconductor UBe13. We clearly observe an absorption peak whose
frequency- and temperature-dependence scales with the BCS gap function.
Resonant absorption into a collective mode, with energy approximately
proportional to the superconducting gap, is proposed as a possible
explantation
Impurity scattering in unconventional density waves
We have investigated the effect of nonmagnetic impurities on the
quasi-one-dimensional unconventional density wave (UDW) ground state. The
thermodynamics were found to be close to those of a d-wave superconductor in
the Born limit. Four different optical conductivity curves were found depending
on the direction of the applied electric field and on the wavevector dependence
of the gap.Comment: 14 pages, 9 figure
Anisotropic Optical Conductivity of Nd2-xCexCuO4 Thin Films
Opticcal conductivity spectra of Nd2-xCexCuO4 thin films,
measured by the reflectance-transmittance method (R-T method) which has been
proposed to investigate far-infrared spectroscopy, are investigated based on
the anisotropic pairing model. Precise measurements of the frequency-dependent
conductivity enable us to examine quantitatively the nature of the
superconducting gap through infrared properties in the electron-doped high-Tc
superconductors. We show that the behavior of optical conductivity
is consistent with the anisotropic superconducting gap and is well explained by
the formula for d-wave pairing in the low-energy regime of the far-infrared
region. Our results suggest that the electron-doped cuprate superconductors
Nd2-xCexCuO4 have nodes in the superconducting gap.Comment: 4 pages, 3 figure
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