4,059 research outputs found
The Spin Stiffness and the Transverse Susceptibility of the Half-filled Hubbard Model
The spin stiffness and the transverse susceptibility of the square lattice half-filled Hubbard model are calculated as a
function of the Hubbard parameter ratio by series expansions around the
Ising limit. We find that the calculated spin-stiffness, transverse
susceptibility, and sublattice magnetization for the Hubbard model smoothly
approach the Heisenberg values for large . The results are compared for
different with RPA and other numerical studies.Comment: 9 Revtex pages, 3 Postscript figures, Europhys. Lett. in pres
Helical and nonhelical (magneto-)Burgers turbulence: I. Compressibility reduction and beyond
We compare the helical and nonhelical (magneto-)Burgers turbulence for the
\textit{helicity fastening effect}. Theoretical arguments and heuristic
mathematical analysis are offered for the latter notion in the new system
loosing some ``nice'' properties as previously used in addressing the
Navier-Stokes and various plasma fluids. Miscellaneous discussions are also
offered, including the inferences of several consequences on the transports of
passive scalars for both the density and tracer, particularly, the opposite
consequences of the helicity fastening effect for the latter two scalars in
appropriate situations (with the caveat of the possibility of the inverse
cascade of the tracer energy). Basic numerical results of the fractions of the
parallel-mode spectra, with maximally-helical random forcing on some
small-wavenumber modes, present a benefit of about over those with
nonhelical forcing, indicating regularization (to some degree) of the
solutions. Such helicity ``fastening'' effect of Burgers turbulence is much
more marked than that for low-Mach-number Navier-Stokes turbulence. The
magnetic helicity in magneto-Burgers dynamics can present an even stronger
benefit, of around
Superfluid and magnetic states of an ultracold Bose gas with synthetic three-dimensional spin-orbit coupling in an optical lattice
We study ultracold bosonic atoms with the synthetic three-dimensional
spin-orbit (SO) coupling in a cubic optical lattice. In the superfluidity
phase, the lowest energy band exhibits one, two or four pairs of degenerate
single-particle ground states depending on the SO-coupling strengths, which can
give rise to the condensate states with spin-stripes for the weak atomic
interactions. In the deep Mott-insulator regime, the effective spin Hamiltonian
of the system combines three-dimensional Heisenberg exchange interactions,
anisotropy interactions and Dzyaloshinskii-Moriya interactions. Based on Monte
Carlo simulations, we numerically demonstrate that the resulting Hamiltonian
with an additional Zeeman field has a rich phase diagram with spiral, stripe,
vortex crystal, and especially Skyrmion crystal spin-textures in each xy-plane
layer. The obtained Skyrmion crystals can be tunable with square and hexagonal
symmetries in a columnar manner along the z axis, and moreover are stable
against the inter-layer spin-spin interactions in a large parameter region.Comment: 9 pages, 4 figures; title modified, references and discussions added;
accepted by PR
Phase Transitions in the Symmetric Kondo Lattice Model in Two and Three Dimensions
We present an application of high-order series expansion in the coupling
constants for the ground state properties of correlated lattice fermion
systems. Expansions have been generated up to order for and
for for certain properties of the symmetric Kondo lattice
model. Analyzing the susceptibility series, we find evidence for a continuous
phase transition from the ``spin liquid'' phase characteristic of a ``Kondo
Insulator'' to an antiferromagnetically ordered phase in dimensions as
the antiferromagnetic Kondo coupling is decreased. The critical point is
estimated to be at for square lattice and
for simple-cubic lattice.Comment: 12 pages, Revtex, replace previous corrupted fil
MicroRNA-186 suppresses cell proliferation and metastasis in bladder cancer
Purpose: Bladder cancer (BCa) is a common malignancy in the urinary system. This study aims to explore the role of miR-186 in BCa tumorigenesis.
Methods: The expression of miR-186 and ADAMTS12 in clinical BCa tissues and cell lines was detected. BCa cell lines T24, 5637 and EJ were used to transfect miR-186 mimics or inhibitors. Luciferase reporter gene detection confirmed the correlation between miR-186 and ADAMTS12. MTT method and flow cytometry were used to detect cell viability and apoptosis. Cell migration and invasion ability was detected by transwell assay. The protein level of ADAMTS12, β-catenin, GSK-3β and p-GSK-3β was determined using western blot analysis.
Results: MiR-186 was negatively correlated with the expression of ADAMTS12 in BCa tissues. Further research confirmed that ADAMTS12 is the direct target of miR-186. In addition, overexpression of miR-186 down-regulated the expression of ADAMTS12,inhibiting cell viability and apoptosis, while knockout of miR-186 led to the opposite result. miR-186 also inhibits the phosphorylation of GSK-3 β and β-catenin without changing the total GSK-3β level. Our study shows that miR-186 has a negative regulatory effecton the expression of ADAMTS12 in clinical specimens and in vitro. miR-186 can inhibit the proliferation and invasion of BCa cells.
Conclusions: miR-186 has the potential to be used as a biomarker in the early detection of BCa.
Keywords: Purpose: Bladder cancer (BCa) is a common malignancy in the urinary system. This study aims to explore the role of miR-186 in BCatumorigenesis.Methods: The expression of miR-186 and ADAMTS12 in clinical BCa tissues and cell lines was detected. BCa cell lines T24, 5637 andEJ were used to transfect miR-186 mimics or inhibitors. Luciferase reporter gene detection confirmed the correlation between miR-186 and ADAMTS12. MTT method and flow cytometry were used to detect cell viability and apoptosis. Cell migration and invasionability was detected by transwell assay. The protein level of ADAMTS12, β-catenin, GSK-3β and p-GSK-3β was determined usingwestern blot analysis.Results: MiR-186 was negatively correlated with the expression of ADAMTS12 in BCa tissues. Further research confirmed thatADAMTS12 is the direct target of miR-186. In addition, overexpression of miR-186 down-regulated the expression of ADAMTS12,inhibiting cell viability and apoptosis, while knockout of miR-186 led to the opposite result. miR-186 also inhibits the phosphorylationof GSK-3 β and β-catenin without changing the total GSK-3β level. Our study shows that miR-186 has a negative regulatory effecton the expression of ADAMTS12 in clinical specimens and in vitro. miR-186 can inhibit the proliferation and invasion of BCa cells.Conclusions: miR-186 has the potential to be used as a biomarker in the early detection of BCa.Keywords: miR-186; ADAMTS12; bladder cancer; proliferation; metastasis biomarker
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