The Spin Stiffness and the Transverse Susceptibility of the Half-filled Hubbard Model

The $T=0$ spin stiffness $\rho _{s}$ and the transverse susceptibility $\chi _{\perp }$ of the square lattice half-filled Hubbard model are calculated as a function of the Hubbard parameter ratio $U/t$ 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 $U/t$. The results are compared for different $U/t$ 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 $0.2$ 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 $0.5+$

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 $(t/J)^{14}$ for $d=1$ and $(t/J)^8$ for $d=2,\ 3$ 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 $d\ge2$ as the antiferromagnetic Kondo coupling is decreased. The critical point is estimated to be at $(t/J)_c\approx0.7$ for square lattice and $(t/J)_c\approx0.5$ 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