12,387 research outputs found
Quality of life in first-admitted schizophrenia patients: a follow-up study
http://journals.cambridge.org/action/logi
Symmetrization and enhancement of the continuous Morlet transform
The forward and inverse wavelet transform using the continuous Morlet basis
may be symmetrized by using an appropriate normalization factor. The loss of
response due to wavelet truncation is addressed through a renormalization of
the wavelet based on power. The spectral density has physical units which may
be related to the squared amplitude of the signal, as do its margins the mean
wavelet power and the integrated instant power, giving a quantitative estimate
of the power density with temporal resolution. Deconvolution with the wavelet
response matrix reduces the spectral leakage and produces an enhanced wavelet
spectrum providing maximum resolution of the harmonic content of a signal.
Applications to data analysis are discussed.Comment: 12 pages, 8 figures, 2 tables, minor revision, final versio
Nuclear energy density functional from chiral pion-nucleon dynamics
We calculate the nuclear energy density functional relevant for N=Z even-even
nuclei in the systematic framework of chiral perturbation theory. The
calculation includes the one-pion exchange Fock diagram and the iterated
one-pion exchange Hartree and Fock diagrams. From these few leading order
contributions in the small momentum expansion one obtains already a very good
equation of state of isospin symmetric nuclear matter. We find that in the
region below nuclear matter saturation density the effective nucleon mass
deviates by at most 15% from its free space value ,
with for and
for higher densities. The parameterfree strength of
the -term, , is at saturation density
comparable to that of phenomenological Skyrme forces. The magnitude of
accompanying the squared spin-orbit density comes out
somewhat larger. The strength of the nuclear spin-orbit interaction,
, as given by iterated one-pion exchange is about half as large as
the corresponding empirical value, however, with the wrong negative sign. The
novel density dependencies of and
as predicted by our parameterfree calculation should be examined in nuclear
structure calculations (after introducing an additional short range spin-orbit
contribution constant in density).Comment: 16 pages, 5 figure
Do different subjective evaluation criteria reflect distinct constructs?
This is not the published version. Published version available from: http://journals.lww.com/jonmd/pages/default.asp
Scattering of decuplet baryons in chiral effective field theory
A formalism for treating the scattering of decuplet baryons in chiral
effective field theory is developed. The minimal Lagrangian and potentials in
leading-order SU(3) chiral effective field theory for the interactions of octet
baryons () and decuplet baryons () for the transitions ,
, , , , and are provided. As an application of the formalism we compare
with results from lattice QCD simulations for and
scattering. Implications of our results pertinent to the quest for dibaryons
are discussed.Comment: 26 pages, 6 figures; minor corrections in the text, references adde
Hyperons in nuclear matter from SU(3) chiral effective field theory
Brueckner theory is used to investigate the properties of hyperons in nuclear
matter. The hyperon-nucleon interaction is taken from chiral effective field
theory at next-to-leading order with SU(3) symmetric low-energy constants.
Furthermore, the underlying nucleon-nucleon interaction is also derived within
chiral effective field theory. We present the single-particle potentials of
Lambda and Sigma hyperons in symmetric and asymmetric nuclear matter computed
with the continuous choice for intermediate spectra. The results are in good
agreement with the empirical information. In particular, our calculation gives
a repulsive Sigma-nuclear potential and a weak Lambda-nuclear spin-orbit force.Comment: 13 pages, 10 figures, 5 tables; v2: published version, minor change
Electron tunnel sensor technology
Researchers designed and constructed a novel electron tunnel sensor which takes advantage of the mechanical properties of micro-machined silicon. For the first time, electrostatic forces are used to control the tunnel electrode separation, thereby avoiding the thermal drift and noise problems associated with piezoelectric actuators. The entire structure is composed of micro-machined silicon single crystals, including a folded cantilever spring and a tip. The application of this sensor to the development of a sensitive accelerometer is described
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