Three unique sequences derived from the Y chromosome have been mapped within the human genome. A Y specific sequence DYS20 is localised to Yq11.2. DXYS25 and DXYS27 are both X-Y homologous sequences which map to the Y short arm and to Xq21. DXYS25 maps more distally than DXYS27, on the Y short arm and on the X long arm. Y specific restriction fragments for these two sequences are shown to be pr...

In this paper we study the structure and the commutativity of a ring R, in which for each x,y ? R, there exist two integers depending on x,y such that [x,y]k equals x n or y n.

Beauquier and Nivat introduced and gave a characterization of the class of pseudo-square polyominoes that tile the plane by translation: a polyomino tiles the plane by translation if and only if its boundary word W may be factorized as W = XY X Y . In this paper we consider the subclass PSP of pseudo-square polyominoes which are also parallelogram. By using the Beauquier-Nivat characterization ...

In this paper we find all solutions of four kinds of the Diophantine equations begin{equation*} ~x^{2}pm V_{t}xy-y^{2}pm x=0text{ and}~x^{2}pm V_{t}xy-y^{2}pm y=0, end{equation*}% for an odd number $t$, and, begin{equation*} ~x^{2}pm V_{t}xy+y^{2}-x=0text{ and}text{ }x^{2}pm V_{t}xy+y^{2}-y=0, end{equation*}% for an even number $t$, where $V_{n}$ is a generalized Lucas number. This pape...

Según la OMS (1), el tabaquismo y el alcoholismo son las drogodependencias más extendidas en nuestra sociedad, y representan, respectivamente, la primera y la tercera causa de años de vida con discapacidades. El Observatorio Español sobre Drogas asegura en su último informe que la mayoría de los españoles consume bebidas alcohólicas esporádica o habitualmente (2). En 2008, 72,9% de estudiantes ...

This paper deals with the boundary value problem involving the differential equation begin{equation*}     ell y:=-y''+qy=lambda y,  end{equation*}  subject to the standard boundary conditions along with the following discontinuity  conditions at a point $ain (0,pi)$  begin{equation*}     y(a+0)=a_1 y(a-0),quad y'(a+0)=a_1^{-1}y'(a-0)+a_2 y(a-0), end{equation*} where $q(x),  a_1 , a_2$ are  rea...