Let X be a completely regular space and let A(X) be a ring of continuous real-valued functions onX which is closed under local bounded inversion. We show that the structure space of A(X) is homeomorphic to a quotient of the Stone–Čech compactification of X. We use this result to show that any realcompactification of X is homeomorphic to a subspace of the structure space of some ring of continuo...

We show that if a variety V of monotone lattice expansions is finitely generated, then profinite completions agree with canonical extensions on V . The converse holds for varieties of finite type. It is a matter of folklore that the profinite completion of a Boolean algebra B is given by the power set of the Stone space of B, or in the terminology of Jónsson and Tarski [5], by the canonical ext...

We have modeled magneto-dielectric phase transitions in ABX3-type layered triangular lattice compounds. The model consists of a spin system (magnetic transition) and a lattice system (dielectric transition). Magnetic exchange interactions are supposed to change with a relative position between two spins. This assumption produces an effective coupling between the lattice and the spin. Applying t...

A lower bound of the form ( 2n n+1 ) 1 n γ n−1 n n−1 is derived on the coding gain γn of the densest n-dimensional (n-D) lattice(s). The bound is obtained based on constructing an n-D lattice which consists of parallel layers. Each layer is selected as a translated version of a densest (n − 1)-D lattice. The relative positioning of the layers is adjusted to make the coding gain as large as poss...

In the general mixed-integer case, the family of Chvátal-Gomory cuts does not comply with (i) and (ii) (see, for example, [8]). Therefore, we need to use a larger family of cutting planes. A polyhedron L ⊆ R is said to be lattice-free if L does not contain points of Z×R in its relative interior. An integral lattice-free cut for K is a linear inequality valid for conv(K \ rel.int(L)), where L is...

in this paper we give an elementary argument about the atoms and coatoms of the latticeof all subgroups of a group. it is proved that an abelian group of finite exponent is strongly coatomic.

We describe the design and implementation of a two-dimensional optical lattice of double wells suitable for isolating and manipulating an array of individual pairs of atoms in an optical lattice. Atoms in the square lattice can be placed in a double well with any of their four nearest neighbors. The properties of the double well the barrier height and relative energy offset of the paired sites ...

OBJECTIVE To study the impact of tamsulosin on the rate of spontaneous passage of distal ureteral stones. METHODS A total of 100 patients with stones sized 10 mm or smaller, located in the distal part of the ureter were included. Patients were randomly assigned to 2 equal groups. Group 1 received 0.4 mg tamsulosin once daily and group 2 received placebo. The investigators and the patients wer...

In this paper, a simple method is proposed to obtain steady analytical solutions for the lattice Boltzmann method. Based on such analytical results, it is demonstrated how the accuracy of the lattice Boltzmann method can depend on the relative orientation of the lattice and the flow field. It is also demonstrated that the method can be useful to obtain a general class of analytical solutions fo...

The effect of interaction of low-index atomic planes, (100), (110), and (111) terminating CdSe platelet nanocrystals is examined using molecular dynamics (MD) simulations. Asymmetry of the environment of atoms at the end surface layers leads to anisotropic deformation of the cubic lattice and to a relative shift of Cd and Se sub-lattices. Interference of distortions of the crystal lattice origi...