2,226 research outputs found
Self-consistent treatment of the self-energy in nuclear matter
The influence of hole-hole propagation in addition to the conventional
particle-particle propagation, on the energy per nucleon and the momentum
distribution is investigated. The results are compared to the
Brueckner-Hartree-Fock (BHF) calculations with a continuous choice and
conventional choice for the single-particle spectrum. The Bethe-Goldstone
equation has been solved using realistic interactions. Also, the structure
of nucleon self-energy in nuclear matter is evaluated. All the self-energies
are calculated self-consistently. Starting from the BHF approximation without
the usual angle-average approximation, the effects of hole-hole contributions
and a self-consistent treatment within the framework of the Green function
approach are investigated. Using the self-consistent self-energy, the hole and
particle self-consistent spectral functions including the particle-particle and
hole-hole ladder contributions in nuclear matter are calculated using realistic
interactions. We found that, the difference in binding energy between both
results, i.e. BHF and self-consistent Green function, is not large. This
explains why is the BHF ignored the 2h1p contribution.Comment: Preprint 20 pages including 15 figures and one tabl
Case Report: Oral–Facial–Digital Syndrome type VI with self mutilations
We report the case of a 2.5 year old female, 2nd in order of birth of 1st cousin consanguineous marriage, with the typical features of Oral–Facial–Digital Syndrome type VI (OFDS VI) including midline pseudo cleft upper lip, sublingual nodule, molar tooth sign by MRI brain, bilateral mesoaxial polydactyly (hexadactyly), and developmental delay. The patient had self mutilations which was not reported before in OFDS VI except once.Keywords: Oral–Facial–Digital Syndrome type VI; Varadi–Papp syndrome; Self mutilation; Polydactyly; Molar tooth sign; Peudocleft li
Case Report: Meier-Gorlin syndrome: Report of an additional patient with congenital heart disease
We report a 7 year old female child with the classical triad of Meier-Gorlin syndrome (MGS), (microtia, absent patella and short stature). She had the characteristic facial features, with normal mentality and defective speech, skeletal abnormalities, conductive hearing loss, cystitis and normal growth hormone level. She suffered from recurrent chest infection during the first year of life which improved gradually with age. Although congenital heart is rarely observed in MGS, our patient had in addition fenestrated interatrial septal defect.Keywords Meier-Gorlin syndrome; Ear-patella-short stature syndrome; Primordial dwarfism; Microtia; Absent patell
Geodesics and Geodesic Deviation in static Charged Black Holes
The radial motion along null geodesics in static charged black hole
space-times, in particular, the Reissner-Nordstr\"om and stringy charged black
holes are studied. We analyzed the properties of the effective potential. The
circular photon orbits in these space-times are investigated. We found that the
radius of circular photon orbits in both charged black holes are different and
differ from that given in Schwarzschild space-time. We studied the physical
effects of the gravitational field between two test particles in stringy
charged black hole and compared the results with that given in Schwarzschild
and Reissner-Nordstr\"om black holes.Comment: 12 pages, 5 figures, small changes, figures and references added,
conclusions changed. A improved, version accepted in Astrophysics and Space
Scienc
Does complimentary information from multispectral imaging improve face presentation attack detection?
Presentation Attack Detection (PAD) has been extensively studied,
particularly in the visible spectrum. With the advancement of sensing
technology beyond the visible range, multispectral imaging has gained
significant attention in this direction. We present PAD based on multispectral
images constructed for eight different presentation artifacts resulted from
three different artifact species. In this work, we introduce Face Presentation
Attack Multispectral (FPAMS) database to demonstrate the significance of
employing multispectral imaging. The goal of this work is to study
complementary information that can be combined in two different ways (image
fusion and score fusion) from multispectral imaging to improve the face PAD.
The experimental evaluation results present an extensive qualitative analysis
of 61650 sample multispectral images collected for bonafide and artifacts. The
PAD based on the score fusion and image fusion method presents superior
performance, demonstrating the significance of employing multispectral imaging
to detect presentation artifacts.Comment: Accepted in International IEEE Applied Sensing Conference (IEEE
APSCON) 202
Energy and Momentum densities of cosmological models, with equation of state , in general relativity and teleparallel gravity
We calculated the energy and momentum densities of stiff fluid solutions,
using Einstein, Bergmann-Thomson and Landau-Lifshitz energy-momentum complexes,
in both general relativity and teleparallel gravity. In our analysis we get
different results comparing the aforementioned complexes with each other when
calculated in the same gravitational theory, either this is in general
relativity and teleparallel gravity. However, interestingly enough, each
complex's value is the same either in general relativity or teleparallel
gravity. Our results sustain that (i) general relativity or teleparallel
gravity are equivalent theories (ii) different energy-momentum complexes do not
provide the same energy and momentum densities neither in general relativity
nor in teleparallel gravity. In the context of the theory of teleparallel
gravity, the vector and axial-vector parts of the torsion are obtained. We show
that the axial-vector torsion vanishes for the space-time under study.Comment: 15 pages, no figures, Minor typos corrected; version to appear in
International Journal of Theoretical Physic
Numerical Studies of a Supersonic Fluidic Diverter Actuator for Flow Control
The analysis of the internal flow structure and performance of a specific fluidic diverter actuator, previously studied by time-dependent numerical computations for subsonic flow, is extended to include operation with supersonic actuator exit velocities. The understanding will aid in the development of fluidic diverters with minimum pressure losses and advanced designs of flow control actuators. The self-induced oscillatory behavior of the flow is successfully predicted and the calculated oscillation frequencies with respect to flow rate have excellent agreement with our experimental measurements. The oscillation frequency increases with Mach number, but its dependence on flow rate changes from subsonic to transonic to supersonic regimes. The delay time for the initiation of oscillations depends on the flow rate and the acoustic speed in the gaseous medium for subsonic flow, but is unaffected by the flow rate for supersonic condition
Energy Distribution of a Stringy Charged Black Hole
The energy distribution associated with a stringy charged black hole is
studied using M{\o}ller's energy-momentum complex. Our result is reasonable and
it differs from that known in literature using Einstein's energy-momentum
complex.Comment: Latex, no figure
Energy and Momentum Distributions of Kantowski and Sachs Space-time
We use the Einstein, Bergmann-Thomson, Landau-Lifshitz and Papapetrou
energy-momentum complexes to calculate the energy and momentum distributions of
Kantowski and Sachs space-time. We show that the Einstein and Bergmann-Thomson
definitions furnish a consistent result for the energy distribution, but the
definition of Landau-Lifshitz do not agree with them. We show that a signature
switch should affect about everything including energy distribution in the case
of Einstein and Papapetrou prescriptions but not in Bergmann-Thomson and
Landau-Lifshitz prescriptions.Comment: 12 page
Acute neuromodulation restores spinally-induced motor responses after severe spinal cord injury
Epidural electrical spinal stimulation can facilitate recovery of volitional motor control in individuals that have been completely paralyzed for more than a year. We recently reported a novel neuromodulation method named Dynamic Stimulation (DS), which short-lastingly increased spinal excitability and generated a robust modulation of locomotor networks in fully-anesthetized intact adult rats. In the present study, we applied repetitive DS patterns to four lumbosacral segments acutely after a contusive injury at lumbar level. Repetitive DS delivery restored the spinally-evoked motor EMG responses that were previously suppressed by a calibrated spinal cord contusion. Sham experiments without DS delivery did not allow any spontaneous recovery. Thus, DS uniquely provides the potential for a greater long-term functional recovery after paralysis
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