5,634 research outputs found
New cosmological constraints with extended-Baryon Oscillation Spectroscopic Survey DR14 quasar sample
We update the constraints on the cosmological parameters by adopting the
Planck data released in 2015 and Baryon Acoustic Oscillation (BAO) measurements
including the new DR14 quasar sample measurement at redshift , and we
conclude that the based six-parameter CDM model is preferred.
Exploring some extensions to the CDM models, we find that the equation
of state of dark energy reads in the CDM model, the
effective relativistic degrees of freedom in the Universe is
in the CDM model and
the spatial curvature parameter is in the
CDM model at confidence level (C.L.), and the
C.L. upper bounds on the sum of three active neutrinos masses are eV for the normal hierarchy (NH) and eV for the
inverted hierarchy (IH) with .Comment: 9 pages, 5 figures, 4 table
Complete phase diagram and topological properties of interacting bosons in one-dimensional superlattices
The interacting bosons in one-dimensional inversion-symmetric superlattices
are investigated from the topological aspect. The complete phase diagram is
obtained by an atomic-limit analysis and quantum Monte Carlo simulations and
comprises three kinds of phases: superfluid, persisted charge-density-wave and
Mott insulators, and emergent insulators in the presence of nearest-neighbor
hoppings. We find that all emergent insulators are topological, which are
characterized by the Berry phase and a pair of degenerate in-gap boundary
states. The mechanism of the topological bosonic insulators is qualitatively
discussed and the ones with higher fillings can be understood as a
-filling topological phase on a background of trivial
charge-density-wave or Mott insulators.Comment: 6 pages, 8 figures. Accelpted for publication in Phys. Rev.
Management of duodenal trauma
AbstractDuodenal trauma is uncommon but nowadays seen more and more frequently due to the increased automobile accidents and violent events. The management of duodenal trauma can be complicated, especially when massive injury to the pancreatic-duodenal-biliary complex occurs simultaneously. Even the patients receive surgeries in time, multiple postoperative complications and high mortality are common. To know and manage duodenal trauma better, we searched the recent related literature in PubMed by the keywords of duodenal trauma, therapy, diagnosis and abdomen. It shows that because the diagnosis and management are complicated and the mortality is high, duodenal trauma should be treated in time and tactfully. And application of new technology can help improve the management. In this review, we discussed the incidence, diagnosis, management, and complications as well as mortality of duodenal trauma
Spin singlet pairing in the superconducting state of NaxCoO2\cdot1.3H2O: evidence from a ^{59}Co Knight shift in a single crystal
We report a ^{59}Co Knight shift measurement in a single crystal of the
cobalt oxide superconductor Na_{x}CoO_2\cdot1.3H_2O (T_c=4.25 K). We find that
the shift due to the spin susceptibility, K^s, is substantially large and
anisotropic, with the spin shift along the a-axis K^s_a being two times that
along the c-axis K^s_c. The shift decreases with decreasing temperature (T)
down to T\sim100 K, then becomes a constant until superconductivity sets in.
Both K^s_a and K^s_c decrease below T_c. Our results indicate unambiguously
that the electron pairing in the superconducting state is in the spin singlet
form.Comment: 4 pages, 5 figure
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