Vibrational infrared intensities and polar tensors of 1,2-difluoroethylenes.

The polar tensors of cis and trans-1,2-difluoroethylenes have been determined with new normal modes based in a reassignment of nu(7) and nu(12) bands of the trans isomers and frequency values corrected for Fermi resonances and phase shifts. The signs of the dipole moment derivatives (and its directions, for B(u) symmetry species) were considered to be those of MP2/6-31G** estimates. Root mean square errors calculated for the new tensor element values from each pair of isotopomers (trans-1,2-C(2)H(2)F(2)/trans-1,2-C(2)D(2)F(2) and cis-1,2-C(2)H(2)F(2)/cis-1,2-C(2)D(2)F(2)) show that the new polar tensor sets fit the isotopic invariance criterion better than previously reported sets. The accuracy of polar tensor transference procedures was tested by calculating the infrared intensities of trans-1,2-C(2)H(2)F(2) through the new polar tensors of the cis isomer. The resulting estimates are very accurate and also support the new band assignment, though the A(6) intensity remains still somewhat underestimated.

Molecular orbital anharmonic estimates for the infrared spectrum of CO2.

The vibrational spectrum of CO2 up to second overtones has been calculated at four different ab initio levels using second order perturbation theory equations in a simplified manner, in which just a few cross-terms suitable for numerical estimation are considered in the Taylor series representing the potential energy and dipole moment functions. The series coefficients are obtained through polynomial regression of estimated single point energy and dipole values for a few distorted geometries along each normal coordinate. The effect of Fermi resonance on near-degenerate energy levels was also taken into account through the usual first order perturbation equations. MP2/6-31G(extended) frequency estimates have a root mean square error of just 32.14 cm(-1). This accuracy is achieved partly due to the underestimation of the harmonic frequencies, which compensates for the neglect of the cross-term chi(ij) anharmonic constants. The chi(ii) constants which depend on cubic and quartic energy coefficients are reasonably well estimated at all ab initio levels. The energy coefficient beta(sbb) responsible for the magnitude of the Fermi resonance is estimated with a maximum error of just 13%. Despite the inclusion of anharmonicities, errors for band intensities are still much larger than for the frequencies. Both electrical and mechanical anharmonicities may be equally important to the band intensity.

Novo sistema de monitorizaçäo de EEG ambulatorial: metodologia de análise do registro e classificaçäo das descargas epilépticas em 100 pacientes / New system for ambularoty EEG monitoring: analysis and classification of epileptic discharge en 100 patients

Desde 1994 vem sendo utilizado no Brasil um equipamento de monitorização eletrencefalográfica ambulatorial (Holter Cerebral) que foi desenvolvido com união da iniciativa privada e a Universidade Federal de São Paulo - UNIFESP. O objetivo deste estudo foi estabelecer um método de análise, uma classificação das descargas epilépticas encontradas e analisar os resultados da monitorização ambulatorial dos primeiros 100 exames consecutivos de pacientes epilépticos e não-epilépticos, adultos ou crianças, realizados no Setor de Investigação e Tratamento das Epilepsias da UNIFESP. Neste estudo foi possível a identificação de descargas paroxísticas epilépticas e de anormalidades da atividade elétrica cardíaca durante atividades da vida diária dos pacientes.

O Plano Diretor de Informações do Ministério da Saúde: uma estratégia para sua elaboração / Information Director Plan from Health Department: a strategy for its elaboration

Divulga a estratégia estabelecida para o processo de elaboração do Plano Diretor de Informações optando pelo planejamento contingente, o que lhe garante maior eficiência no aproveitamento do esforço criador e maior eficácia para as ações subseqüentes: aquelas que dependem dos resultados obtidos com a execução das imediatamente anteriores