We study the chemisorption of CO molecule into sites of different coordination on (111) surfaces of late 4d and 5d transition metals. In an attempt to solve the well-known CO adsorption puzzle we have applied the relatively new vdW-DF theory of nonlocal correlation. The application of the vdW-DF functional in all considered cases improves or completely solves the discrepancies of the adsorption site preference and improves the value of the adsorption energy. By introducing a cutoff distance for nonlocal interaction we pinpoint the length scale at which the correlation plays a major role in the systems considered.

Nowadays the state of the art Density Functional Theory (DFT) codes are based on local (LDA) or semilocal (GGA) energy functionals. Recently the theory of a truly nonlocal energy functional has been developed. It has been used mostly as a post DFT calculation approach, i.e. by applying the functional on the charge density calculated using any standard DFT code, thus obtaining a new improved value for the total energy of the system. Nonlocal calculation is computationally quite expensive and scales as N^2 where N is the number of points in which charge density is defined, and a massively parallel calculation is essential for a wider applicability of the new approach. In this article we present a code which acomplishes this goal.

Computational grids are a promising resource for modeling complex biochemical processes such as protein folding, penetration of gases or water into proteins, or protein structural rearrangements coupled to ligand binding. We have enabled the molecular dynamics program CHARMM to run on the Open Science Grid. The implementation is general, flexible, easily modifiable for use with other molecular dynamics programs and other grids and automated in terms of job submission, monitoring, and resubmission. The usefulness of grid computing was demonstrated through the study of hydration of the Glu-66 side chain in the interior of protein staphylococcal nuclease. Multiple simulations started with and without two internal water molecules shown crystallographically to be associated with the side chain of Glu-66 yielded two distinct populations of rotameric states of Glu-66 that differed by as much as 20%. This illustrates how internal water molecules can bias protein conformations. Furthermore, there appeared to be a temporal correlation between dehydration of the side chain and conformational transitions of Glu-66. This example demonstrated how difficult it is to get convergence even in the relatively simple case of a side chain oscillating between two conformations. With grid computing, we also benchmarked the self-guided Langevin dynamics method against the Langevin dynamics method traditionally used for temperature control in molecular dynamics simulations and showed that the two methods yield comparable results.

Sleeping disorders in type 2 diabetic patients constitute risk factors for aggravating diabetes since they can affect the metabolic control through insulin resistance syndrome. This was an observational, cross-sectional study. The majority (52%) of subjects had scores indicating poor sleep quality. The Pittsburgh Sleep Quality Index (PSQI) scores showed patients with a time after diagnosis over 10 years and hypertension had the poorest sleep quality. For those with hemoglobin A1c >7% taking sleeping medicines and those who had normal body mass index (BMI), the sleep quality was even poorer. The findings of the present study reinforce the relevance of this topic since there are no specific tools for sleep evaluation of type 2 diabetics making it difficult to make any assertions on the sleep quality of these patients. DESCRIPTORS: sleep disorders; diabetes mellitus, type 2; quality of life

JUSTIFICATIVA E OBJETIVOS: Os testes de coagulacao (hemograma e tempo de protrombina) foram inicialmente concebidos como uma forma de rastrear e acompanhar coagulopatias congenitas raras e o hemograma e o que fornece o numero de plaquetas por milimetro cubico. O objetivo deste relato foi apresentar o caso de uma paciente que apresentava um numero de plaquetas extremamente baixo quando sua amostra de sangue era analisada em tubo com EDTA e um numero normal quando analisada com citrato, alertando para o risco de administracao erronea de hemoderivados. RELATO DO CASO: Paciente do sexo feminino, 40 anos, ASA II. Em 2001, apresentou plaquetopenia no hemograma e foi encaminhada para o hematologista em Manaus, AM, sendo realizada esplenectomia nesse mesmo ano, com diagnostico de purpura trombocitopenica idiopatica. Com a persistencia da plaquetopenia nos hemogramas foi verificado na ecografia de abdomen: imagem hipoecoica de ecotextura semelhante a esplenica, medindo 2,0 × 1,7 cm, forma esferica, conteudo bem definido (baco acessorio) e indicada esplenectomia de baco acessorio. Apos uma hora de operacao, foram colhidas amostras para hemograma e bioquimica: Hb = 11,3 g.dL-1; Ht = 33,4%; Plaquetas = 35.000.µL-1; TAP = 15,2 (86,0% Atividade) (RNI = 1,09). Em virtude do sangramento minimo no campo cirurgico, foi solicitado novo exame com citrato para dosagem de plaquetas (resultado: 138.000 plaquetas). CONCLUSOES: O resultado anomalo em um exame isolado sem correspondencia com a clinica do paciente nao deve guiar a terapeutica. Todos os exames tem uma porcentagem definida de erros, e a busca desses erros tecnicos impede que uma terapeutica erronea seja usada.