517 research outputs found
Large-Scale Pairwise Sequence Alignments on a Large-Scale GPU Cluster
This paper presents design of a GPU kernel for performing pairwise sequence alignments for large-scale short sequence datasets generated by nextgeneration sequencers. This kernel principally performs batch Needleman– Wunsch global alignments. When used with its MPI-based host software, the kernel is scalable and is capable of achieving high throughput alignment when run on a CPU-GPU cluster
Kabul Times (April 11, 1964, vol. 3, no. 37)
High-resolution photon scattering experiments have been performed on the nucleus 45Sc at the Darmstadt superconducting electron accelerator S-DALINAC using bremsstrahlung beams with end point energies of 5.0 and 7.0MeV. Energies, absolute cross-sections and decay widths of 50 states, most of them previously unknown, have been determined. The results are compared to (γ,) experiments on the neighbouring closed proton shell isotope 44Ca
Multilinear Wavelets: A Statistical Shape Space for Human Faces
We present a statistical model for D human faces in varying expression,
which decomposes the surface of the face using a wavelet transform, and learns
many localized, decorrelated multilinear models on the resulting coefficients.
Using this model we are able to reconstruct faces from noisy and occluded D
face scans, and facial motion sequences. Accurate reconstruction of face shape
is important for applications such as tele-presence and gaming. The localized
and multi-scale nature of our model allows for recovery of fine-scale detail
while retaining robustness to severe noise and occlusion, and is
computationally efficient and scalable. We validate these properties
experimentally on challenging data in the form of static scans and motion
sequences. We show that in comparison to a global multilinear model, our model
better preserves fine detail and is computationally faster, while in comparison
to a localized PCA model, our model better handles variation in expression, is
faster, and allows us to fix identity parameters for a given subject.Comment: 10 pages, 7 figures; accepted to ECCV 201
High count rate {\gamma}-ray spectroscopy with LaBr3:Ce scintillation detectors
The applicability of LaBr3:Ce detectors for high count rate {\gamma}-ray
spectroscopy is investigated. A 3"x3" LaBr3:Ce detector is used in a test setup
with radioactive sources to study the dependence of energy resolution and photo
peak efficiency on the overall count rate in the detector. Digitized traces
were recorded using a 500 MHz FADC and analysed with digital signal processing
methods. In addition to standard techniques a pile-up correction method is
applied to the data in order to further improve the high-rate capabilities and
to reduce the losses in efficiency due to signal pile-up. It is shown, that
{\gamma}-ray spectroscopy can be performed with high resolution at count rates
even above 1 MHz and that the performance can be enhanced in the region between
500 kHz and 10 MHz by using pile-up correction techniques
The decay of quadrupole-octupole states in Ca and Ce
Background: Two-phonon excitations originating from the coupling of two
collective one-phonon states are of great interest in nuclear structure
physics. One possibility to generate low-lying excitations is the coupling
of quadrupole and octupole phonons.
Purpose: In this work, the -decay behavior of candidates for the
state in the doubly-magic nucleus Ca and in
the heavier and semi-magic nucleus Ce is investigated.
Methods: experiments have been carried out at the
High Intensity -ray Source (HIS) facility in combination with
the high-efficiency -ray spectroscopy setup consisting of
HPGe and LaBr detectors. The setup enables the acquisition of
- coincidence data and, hence, the detection of direct decay
paths.
Results: In addition to the known ground-state decays, for Ca the
decay into the state was observed, while for Ce the direct
decays into the and the state were detected. The experimentally
deduced transition strengths and excitation energies are compared to
theoretical calculations in the framework of EDF theory plus QPM approach and
systematically analyzed for isotones. In addition, negative parities for
two states in Ca were deduced simultaneously.
Conclusions: The experimental findings together with the theoretical
calculations support the two-phonon character of the excitation in the
light-to-medium-mass nucleus Ca as well as in the stable even-even
nuclei.Comment: 11 pages, 6 figures, as accepted in Phys. Rev.
Fragmentation and systematics of the Pygmy Dipole Resonance in the stable N=82 isotones
The low-lying electric dipole (E1) strength in the semi-magic nucleus 136Xe
has been measured which finalizes the systematic survey to investigate the
so-called pygmy dipole resonance (PDR) in all stable even N=82 isotones with
the method of nuclear resonance fluorescence using real photons in the entrance
channel. In all cases, a fragmented resonance-like structure of E1 strength is
observed in the energy region 5 MeV to 8 MeV. An analysis of the fragmentation
of the strength reveals that the degree of fragmentation decreases towards the
proton-deficient isotones while the total integrated strength increases
indicating a dependence of the total strength on the neutron-to-proton ratio.
The experimental results are compared to microscopic calculations within the
quasi-particle phonon model (QPM). The calculation includes complex
configurations of up to three phonons and is able to reproduce also the
fragmentation of the E1 strength which allows to draw conclusions on the
damping of the PDR. Calculations and experimental data are in good agreement in
the degree of fragmentation and also in the integrated strength if the
sensitivity limit of the experiments is taken into account
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Reflective diffractometric hydrogel sensor for biological and chemical detection
A reflective diffractometric hydrogel sensor includes an upper layer, including a microfluidic chamber formed from a substantially transparent material and configured to contain a solution, a reflective diffraction grating positioned within the microfluidic chamber, the diffraction grating including a plurality of hydrogel strips configured to change in dimension in response to a stimulus, each hydrogel strip having a top surface coated with a reflective material and a bottom surface in contact with the upper layer substrate, and a reflective surface below the reflective diffraction grating wherein when a coherent light is incident upon and reflected from the upper layer at an angle substantially normal to the upper layer an interference diffraction pattern results, including a first diffraction mode, a light intensity of which indicates the relative distance between the top surfaces of the plurality of hydrogel strips and the reflective surface.Board of Regents, University of Texas Syste
Investigation of octupole vibrational states in 150Nd via inelastic proton scattering (p,p'g)
Octupole vibrational states were studied in the nucleus
via inelastic proton scattering with \unit[10.9]{MeV} protons which are an
excellent probe to excite natural parity states. For the first time in
, both the scattered protons and the rays were
detected in coincidence giving the possibility to measure branching ratios in
detail. Using the coincidence technique, the ratios of the decaying
transitions for 10 octupole vibrational states and other negative-parity states
to the yrast band were determined and compared to the Alaga rule. The positive
and negative-parity states revealed by this experiment are compared with
Interacting Boson Approximation (IBA) calculations performed in the (spdf)
boson space. The calculations are found to be in good agreement with the
experimental data, both for positive and negative-parity states
Isospin properties of electric dipole excitations in 48Ca
Two different experimental approaches were combined to study the electric
dipole strength in the doubly-magic nucleus 48Ca below the neutron threshold.
Real-photon scattering experiments using bremsstrahlung up to 9.9 MeV and
nearly mono-energetic linearly polarized photons with energies between 6.6 and
9.51 MeV provided strength distribution and parities, and an
(\alpha,\alpha'\gamma) experiment at E_{\alpha}=136 MeV gave cross sections for
an isoscalar probe. The unexpected difference observed in the dipole response
is compared to calculations using the first-order random-phase approximation
and points to an energy-dependent isospin character. A strong isoscalar state
at 7.6 MeV was identified for the first time supporting a recent theoretical
prediction.Comment: 6 pages, 5 figures, as accepted in Phys. Lett.
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