2,082 research outputs found
On the nuclear symmetry energy and the neutron skin in neutron-rich nuclei
The symmetry energy for nuclear matter and its relation to the neutron skin
in finite nuclei is discussed. The symmetry energy as a function of density
obtained in a self-consistent Green function approach is presented and compared
to the results of other recent theoretical approaches. A partial explanation of
the linear relation between the symmetry energy and the neutron skin is
proposed. The potential of several experimental methods to extract the neutron
skin is examined.Comment: to appear in Phys. Rev.
Hamiltonian formalism of the Landau-Lifschitz equation for a spin chain with full anisotropy
The Hamiltonian formalism of the Landau-Lifschitz equation for a spin chain
with full anisotropy is formulated completely, which constructs a stable base
for further investigations.Comment: 11page
The gamma-ray telescope Gamma-1
French and Soviet specialists have designed and built the gamma-ray telescope GAMMA-1 to detect cosmic gamma rays above 50 MeV. The sensitive area of the detector is 1400 sq cm, energy resolution is 30% at 300 MeV, and angular resolution 1.2 deg at 300 MeV (and less than 20' arc when a coded aperture mask is used). Results on calibration of the qualification model and Monte-Carlo calculations are presented
Investigation of the 6He cluster structures
The 4He+2n and t+t clustering of the 6He ground state were investigated by
means of the transfer reaction 6He(p,t)4He at 25 MeV/nucleon. The experiment
was performed in inverse kinematics at GANIL with the SPEG spectrometer coupled
to the MUST array. Experimental data for the transfer reaction were analyzed by
a DWBA calculation including the two neutrons and the triton transfer. The
couplings to the 6He --> 4He + 2n breakup channels were taken into account with
a polarization potential deduced from a coupled-discretized-continuum channels
analysis of the 6He+1H elastic scattering measured at the same time. The
influence on the calculations of the 4He+t exit potential and of the triton
sequential transfer is discussed. The final calculation gives a spectroscopic
factor close to one for the 4He+2n configuration as expected. The spectroscopic
factor obtained for the t+t configuration is much smaller than the theoretical
predictions.Comment: 10 pages, 11 figures, accepted in PR
Application of Bayesian network structure learning to identify causal variant SNPs from resequencing data
Using single-nucleotide polymorphism (SNP) genotypes from the 1000 Genomes Project pilot3 data provided for Genetic Analysis Workshop 17 (GAW17), we applied Bayesian network structure learning (BNSL) to identify potential causal SNPs associated with the Affected phenotype. We focus on the setting in which target genes that harbor causal variants have already been chosen for resequencing; the goal was to detect true causal SNPs from among the measured variants in these genes. Examining all available SNPs in the known causal genes, BNSL produced a Bayesian network from which subsets of SNPs connected to the Affected outcome were identified and measured for statistical significance using the hypergeometric distribution. The exploratory phase of analysis for pooled replicates sometimes identified a set of involved SNPs that contained more true causal SNPs than expected by chance in the Asian population. Analyses of single replicates gave inconsistent results. No nominally significant results were found in analyses of African or European populations. Overall, the method was not able to identify sets of involved SNPs that included a higher proportion of true causal SNPs than expected by chance alone. We conclude that this method, as currently applied, is not effective for identifying causal SNPs that follow the simulation model for the GAW17 data set, which includes many rare causal SNPs
Penetration of hot electrons through a cold disordered wire
We study a penetration of an electron with high energy E<<T through strongly
disordered wire of length L<<a (a being the localization length). Such an
electron can loose, but not gain the energy, when hopping from one localized
state to another. We have found a distribution function for the transmission
coefficient t. The typical t remains exponentially small in L/a, but with the
decrement, reduced compared to the case of direct elastic tunnelling. The
distribution function has a relatively strong tail in the domain of anomalously
high t; the average ~(a/L)^2 is controlled by rare configurations of
disorder, corresponding to this tail.Comment: 4 pages, 5 figure
Application of Managing Cancer and Living Meaningfully (CALM) in Advanced Cancer Patients: An Italian Pilot Study.
Depression and anxiety occur in 25–30% of advanced cancer patients, as conditions arising from a final pathway of distress determined by the interaction of multiple factors. Within the psychotherapeutic intervention developed to address these conditions, Managing Cancer and Living Meaningfully (CALM) is an individual meaning and supportive-expressive intervention for patients with advanced cancer. In preliminary pilot studies,CALM was found to decrease depression and anxiety, and
improve spirituality and attachment, while in a randomized clinical trial, CALM reduced depression and improved end-of-life preparation. We conducted a pilot study of CALM using a mixed method approach, in order to: (i) understand the possible application of CALM in a different cultural context (i.e., Italy) and examine the patients’ subjective perception of CALM; and (ii) preliminarily explore, as already done in other countries (i.e., Germany), the possible effects of CALM on a series of psychosocial outcomes
Effect of dipole-dipole charge interactions on dust coagulation
This study examines the effect that dipole-dipole charge interactions between
fractal aggregates have on the growth of dust grains. Aggregates in a plasma or
radiative environment will have charge distributed over their extended surface,
which leads to a net dipole moment for the charged grains. A self-consistent
N-body code is used to model the dynamics of interacting charged aggregates.
The aggregates are free to rotate due to collisions and dipole-dipole
electrostatic interactions. These rotations are important in determining the
growth rate and subsequent geometry (fractal dimension) of the grains. In
contrast to previous studies which have only taken charge-dipole interactions
into account, like-charged grains are found to coagulate more efficiently than
neutral grains due to preferential incorporation of small aggregates into
mid-sized aggregate structures. The charged aggregates tend to be more compact
than neutral aggregates, characterized by slightly higher fractal dimensions
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