Theory of temperature dependence of the Fermi surface-induced splitting of the alloy diffuse-scattering intensity peak

The explanation is presented for the temperature dependence of the fourfold intensity peak splitting found recently in diffuse scattering from the disordered Cu3Au alloy. The wavevector and temperature dependence of the self-energy is identified as the origin of the observed behaviour. Two approaches for the calculation of the self-energy, the high-temperature expansion and the alpha-expansion, are proposed. Applied to the Cu3Au alloy, both methods predict the increase of the splitting with temperature, in agreement with the experimental results.Comment: 4 pages, 3 EPS figures, RevTeX, submitted to J. Phys. Condens. Matter (Letter to the Editor

Screened Coulomb interactions in metallic alloys: II Screening beyond the single-site and atomic sphere approximations

A quantitative description of the configurational part of the total energy of metallic alloys with substantial atomic size difference cannot be achieved in the atomic sphere approximation: It needs to be corrected at least for the multipole moment interactions in the Madelung part of the one-electron potential and energy. In the case of a random alloy such interactions can be accounted for only by lifting the atomic sphere and single-site approximations, in order to include the polarization due to local environment effects. Nevertheless a simple parameterization of the screened Coulomb interactions for the ordinary single-site methods, including the generalized perturbation method, is still possible. We obtained such a parameterization for bulk and surface NiPt alloys, which allows one to obtain quantitatively accurate effective interactions in this system.Comment: 24 pages, 2 figure

Magnetic properties of X-Pt (X=Fe,Co,Ni) alloy systems

We have studied the electronic and magnetic properties of Fe-Pt, Co-Pt and Ni-Pt alloy systems in ordered and disordered phases. The influence of various exchange-correlation functionals on values of equilibrium lattice parameters and magnetic moments in ordered Fe-Pt, Co-Pt and Ni-Pt alloys have been studied using linearized muffin-tin orbital method. The electronic structure calculations for the disordered alloys have been carried out using augmented space recursion technique in the framework of tight binding linearized muffin-tin orbital method. The effect of short range order has also been studied in the disordered phase of these systems. The results show good agreements with available experimental values.Comment: 21 pages, 4 eps figures, accepted for publication in Journal of Physics Condensed Matte

EHMTI-0302. SUNCT syndrome, case report

Photograph of a scene in Gloss Mountain State Park

Supplementary Material for: High Prevalence of Major Neurological Disorders in Two Albanian Communities: Results of a Door-to-Door Survey

<i>Background:</i> There are few epidemiological studies on neurological disorders in Albania. <i>Methods:</i> A door-to-door survey was undertaken in two geographical areas (Tirana and Saranda) with different socioeconomic backgrounds. Two random samples of the local population underwent a structured interview to ascertain headache, epilepsy, dementia, parkinsonism, multiple sclerosis, polyneuropathy, stroke and cerebral palsy. Each diagnosis was made using standard criteria for epidemiological studies and was confirmed by history, neurological examination and, where available, the review of personal medical records. Lifetime prevalence ratios with 95% confidence intervals were calculated. <i>Results:</i> Of the 9,869 individuals screened (Tirana 4,953; Saranda 4,916), 4,867 were males aged 1–91 years (median 39 years) and 5,002 were females aged 1–96 years (median 37 years). Crude prevalence ratios (per 1,000) were: headache 241.9 (233.5–250.3), polyneuropathy 32.5 (29.0–36.0), epilepsy 14.2 (11.7–16.3), stroke 12.4 (10.2–14.6), dementia 9.6 (7.7–11.5), parkinsonism 8.0 (6.2–9.8), cerebral palsy 4.8 (3.4–6.2), and multiple sclerosis 0.3 (0.0–0.6). Prevalence varied with age and gender, with differences across diseases. Except for polyneuropathy (Tirana 39.8; Saranda 25.2), ratios were not different in the two study areas. <i>Conclusions:</i> The prevalence of selected neurological disorders in Albania is higher than in other countries. Differences may be explained by study design, population structure and/or genetic and environmental factors