Poikilodermatous mycosis fungoides: clinical and histopathological analysis of a case and literature review.

Poikilodermatous mycosis fungoides is a rare distinct clinical variant of cutaneous T-cell lymphoma (CTCL), formerly referred to as poikiloderma vasculare atrophicans or parapsoriasis variegata. Mycosis fungoides (MF) is a malignant neoplasm of T-lymphocyte origin, most commonly memory CD4+ T-cells.We report here a patient with generalized poikilodermatous skin lesions whose diagnosis of mycosis fungoides was made only a few years after the onset of his disease due to its bizarre clinical behavior and a natural reluctance to diagnose this disease in children and adolescents.

Exact-exchange spin-density functional theory of Wigner localization and phase transitions in quantum rings.

We apply exact-exchange spin-density functional theory in the Krieger-Li-Iafrate approximation to interacting electrons in quantum rings of different widths. The rings are threaded by a magnetic flux that induces a persistent current. A weak space and spin symmetry breaking potential is introduced to allow for localized solutions.

Evaluation of three serological tests manufactured in Belarus for the diagnosis of syphilis.

The performance of three serological tests manufactured in Belarus for the diagnosis of syphilis, i.e. a microprecipitation reaction (MPR) and two enzyme-linked immunosorbent assays (ELISAs) were compared with internationally recognized assays, namely the rapid plasma reagin test and the Treponema pallidum passive particle agglutination assay (TPPA).

Many-body effects in the excitation spectrum of a defect in SiC.

We show that electron correlations control the photophysics of defects in SiC through both renormalization of the quasiparticle band structure and excitonic effects. We consider the carbon vacancy with two possible excitation channels that involve conduction and valence bands. Corrections to the Kohn-Sham ionization levels strongly depend on the defect charge state.

Density functional study of collective electron localization: detection by persistent current.

We apply the optimized effective potential (OEP) implementation of density functional theory (DFT) to the model system of interacting spinless electrons on a quantum ring. The ring encircles a magnetic flux that induces a persistent current. In a perfect rotationally invariant system the current does not depend on the electron-electron interaction (the latter is characterized by a standard dimensionless parameter r(S)) and hence is not sensitive to the microscopic structure of the electron correlated state.

Ab initio study of graphene on SiC.

Employing density-functional calculations we study single and double graphene layers on Si- and C-terminated 1x1-6H-SiC surfaces. We show that, in contrast with earlier assumptions, the first carbon layer is covalently bonded to the substrate and cannot be responsible for the graphene-type electronic spectrum observed experimentally. The characteristic spectrum of freestanding graphene appears with the second carbon layer, which exhibits a weak van der Waals bonding to the underlying structure.

Epidemiology of syphilis in pregnant women and congenital syphilis in Belarus.

In Belarus the spread of syphilis has been on the increase since 1988, and the incidence reached its peak in 1996 with 209.7 cases per 100 000 inhabitants. During the following years the incidence has reduced, but still remains high with 41 cases in 2004.