Many experimental studies, over the past two decades, have constantly reported a critical behavior for the transition from the smectic- A phase of liquid crystals to the hexatic- B phase with non- XY critical exponents. However, according to symmetry arguments this transition must belong to the XY universality class. Using an optimized Monte Carlo simulation technique based on the multihistogra...

A phase diagram of the anisotropic Heisenberg model with competition between the nearest and the next-to-nearest neighbour exchange interactions is investigated by using thc bosonisation scheme. An instability leading to a spontaneous dimerisation is found. The new 'superfluid' phases with both non-zero, though non-nominal, Z-magnetisation and broken symmetry in the XY-plane are detected in the...

We construct a global bifurcation diagram of the plane differential system ẋ = x(1− x)− xy/(a+ x), ẏ = y(δ − βy/x), x(t) > 0, y(t) > 0, a > 0, δ > 0, β > 0, which describes the predator-prey interaction. In [1] was considered the following planar differential systems which describes a mathematical predator-prey model ẋ = rx(1 − x K )− mx b+x y, ẏ = sy(1− y hx ). (1) Here x(t) > 0, y(t) > 0 — th...

The enhancement of interfacial Dzyaloshinskii-Moriya Interaction (DMI) in magnetic multilayers results the stabilization topological spin textures such as chiral domain walls and skyrmions. Here we report on evaluation interface-driven interactions a uniquely designed multilayer where each layer two antiferromagnetically coupled sublattices $3d$ $4f$ moments is sandwiched between layers \ensure...

We review and analyze magnetization and specific heat investigations on type-II superconductors which uncover remarkable evidence for the magnetic field induced finite size effect and the associated 3D to 1D crossover which enhances thermal fluctuations. Indeed, the correlation length transverse to the magnetic field Hi, applied along the i-axis, cannot grow beyond the limiting magnetic length ...

Graph algebras establish a connection between directed graphs without multiple edges and special universal algebras of type (2, 0). We say that a graph G satisfies an identity s ≈ t if the corresponding graph algebra A(G) satisfies s ≈ t. A graph G = (V, E) is called an (xy)x ≈ x(yy) graph if the graph algebra A(G) satisfies the equation (xy)x ≈ x(yy). An identity s ≈ t of terms s and t of any ...

Six children, with severe deficiency of some or all of the immunoglobulins and minor somatic abnormalities, had chromosomal abnormalities: (1) 45,XY,t(13q/18q), (2) 46,XY,21ps +, (3) two brothers 46,XY (inv. 7) (4) 45,X,t(11p/10p)/46X,iXq,t(11p/10p) and, (5) in addendum, 45,XX,-18;46,XX, r18. The chromosome abnormalities were detected in B- as well as T-lymphocytes (as evidenced by using both P...

Disorders of sex development in the human population range in severity from mild genital defects to gonadal sex reversal. XY female development has been associated with heterozygous mutations in several genes, including SOX9, WT1 and MAP3K1. In contrast, XY sex reversal in mice usually requires complete absence of testis-determining gene products. One exception to this involves T-associated sex...