5,170 research outputs found
Systematic investigation of the rotational bands in nuclei with using a particle-number conserving method based on a cranked shell model
The rotational bands in nuclei with are investigated
systematically by using a cranked shell model (CSM) with the pairing
correlations treated by a particle-number conserving (PNC) method, in which the
blocking effects are taken into account exactly. By fitting the experimental
single-particle spectra in these nuclei, a new set of Nilsson parameters
( and ) and deformation parameters ( and
) are proposed. The experimental kinematic moments of inertia
for the rotational bands in even-even, odd- and odd-odd nuclei, and the
bandhead energies of the 1-quasiparticle bands in odd- nuclei, are
reproduced quite well by the PNC-CSM calculations. By analyzing the
-dependence of the occupation probability of each cranked Nilsson
orbital near the Fermi surface and the contributions of valence orbitals in
each major shell to the angular momentum alignment, the upbending mechanism in
this region is understood clearly.Comment: 21 pages, 24 figures, extended version of arXiv: 1101.3607 (Phys.
Rev. C83, 011304R); added refs.; added Fig. 4 and discussions; Phys. Rev. C,
in pres
Construction, expression, and characterization of rSEA-EGF and in vitro evaluation of its antitumor activity against nasopharyngeal cancer
How User and Requirement Risks Moderate the Effects of Formal and Informal Controls on IT Project Performance
Controlling information technology (IT) projects is a prime concern for both project managers (PMs) and users, yet little is known about how key risks affect the relationship between controls and performance. Based on data collected on 128 completed IT projects, we examine the moderating effects of requirement and user risk on the relationship between controls and process performance from the perspectives of both the project manager and the user liaison. Both risks were found to suppress the relationship between controls and process performance for each group. While both formal and informal control explain a significant amount of variance in process performance, formal control had a more significant role than informal control from the PM perspective, whereas informal controls play a more significant role than formal controls from the user perspective. The relationship between formal control and process performance was found to be stronger for PMs than for users
Observational constraints on cosmic neutrinos and dark energy revisited
Using several cosmological observations, i.e. the cosmic microwave background
anisotropies (WMAP), the weak gravitational lensing (CFHTLS), the measurements
of baryon acoustic oscillations (SDSS+WiggleZ), the most recent observational
Hubble parameter data, the Union2.1 compilation of type Ia supernovae, and the
HST prior, we impose constraints on the sum of neutrino masses (\mnu), the
effective number of neutrino species (\neff) and dark energy equation of
state (), individually and collectively. We find that a tight upper limit on
\mnu can be extracted from the full data combination, if \neff and are
fixed. However this upper bound is severely weakened if \neff and are
allowed to vary. This result naturally raises questions on the robustness of
previous strict upper bounds on \mnu, ever reported in the literature. The
best-fit values from our most generalized constraint read
\mnu=0.556^{+0.231}_{-0.288}\rm eV, \neff=3.839\pm0.452, and
at 68% confidence level, which shows a firm lower limit on
total neutrino mass, favors an extra light degree of freedom, and supports the
cosmological constant model. The current weak lensing data are already helpful
in constraining cosmological model parameters for fixed . The dataset of
Hubble parameter gains numerous advantages over supernovae when ,
particularly its illuminating power in constraining \neff. As long as is
included as a free parameter, it is still the standardizable candles of type Ia
supernovae that play the most dominant role in the parameter constraints.Comment: 39 pages, 15 figures, 7 tables, accepted to JCA
Endothelial Cell Autophagy in Atherosclerosis is Regulated by miR-30-Mediated Translational Control of ATG6
Rotation and alignment of high- orbitals in transfermium nuclei
The structure of nuclei with is investigated systematically by the
Cranked Shell Model (CSM) with pairing correlations treated by a
Particle-Number Conserving (PNC) method. In the PNC method, the particle number
is conserved and the Pauli blocking effects are taken into account exactly. By
fitting the experimental single-particle spectra in these nuclei, a new set of
Nilsson parameters ( and ) is proposed. The experimental kinematic
moments of inertia and the band-head energies are reproduced quite well by the
PNC-CSM calculations. The band crossing, the effects of high- intruder
orbitals and deformation are discussed in detail.Comment: To appear in the Proceedings of the International Nuclear Physics
Conference (INPC2013), June 2-7, 2013, Florence, Ital
Correlation Coefficients for a Study with Repeated Measures
Repeated measures are increasingly collected in a study to investigate the trajectory of measures over time. One of the first research questions is to determine the correlation between two measures. The following five methods for correlation calculation are compared: (1) Pearson correlation; (2) correlation of subject means; (3) partial correlation for subject effect; (4) partial correlation for visit effect; and (5) a mixed model approach. Pearson correlation coefficient is traditionally used in a cross-sectional study. Pearson correlation is close to the correlations computed from mixed-effects models that consider the correlation structure, but Pearson correlation may not be theoretically appropriate in a repeated-measure study as it ignores the correlation of the outcomes from multiple visits within the same subject. We compare these methods with regard to the average of correlation and the mean squared error. In general, correlation under the mixed-effects model with the compound symmetric structure is recommended as its correlation is close to the nominal level with small mean square error
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