Low-energy electron collisions with acetic acid

We present cross sections for elastic collisions of low-energy electrons with acetic acid. We employed the Schwinger multichannel method with pseudopotentials in the static-exchange and static-exchange plus polarization approximations, for energies ranging from 0.1 to 10 eV. We found a pi(*) shape resonance around 1.7 eV, corresponding to the A(') symmetry of the C(s) group. This resonant state was assigned to the experimental dissociative electron attachment peak at 1.7 eV yielding CH(3)COO(-)+H. We also performed a series of electronic structure calculations using a small basis set for acetic, formic, and trifluoroacetic acids, which exhibit a similar behavior with respect to the dissociative electron attachment. We believe that hydrogen elimination triggered off by electron capture into a pi(*) resonance could be a general property of carboxylic acids.79

Comparative cytogenetic analysis between Lonchorhina aurita and Trachops cirrhosus (Chiroptera, Phyllostomidae)

Phyllostomidae comprises the most diverse family of neotropical bats, its wide range of morphological features leading to uncertainty regarding phylogenetic relationships. Seeing that cytogenetics is one of the fields capable of providing support for currently adopted classifications through the use of several markers, a comparative analysis between two Phyllostomidae species was undertaken in the present study, with a view to supplying datasets for the further establishment of Phyllostomidae evolutionary relationships. Karyotypes of Lonchorhina aurita (2n = 32; FN = 60) and Trachops cirrhosus (2n = 30; FN = 56) were analyzed by G- and C-banding, silver nitrate staining (Ag-NOR) and base-specific fluorochromes. Chromosomal data obtained for both species are in agreement with those previously described, except for X chromosome morphology in T. cirrhosus, hence indicating chromosomal geographical variation in this species. A comparison of G-banding permitted the identification of homeologies in nearly all the chromosomes. Furthermore, C-banding and Ag-NOR patterns were comparable to what has already been observed in the family. In both species CMA3 /DA/DAPI staining revealed an R-banding-like pattern with CMA 3 , whereas DAPI showed uniform staining in all the chromosomes. Fluorochrome staining patterns for pericentromeric constitutive heterochromatin (CH) regions, as well as for nucleolar organizing regions (NORs), indicated heterogeneity regarding these sequences among Phyllostomidae species

Electron collisions with the HCOOH center dot center dot center dot(H2O)(n) complexes (n=1, 2) in liquid phase: The influence of microsolvation on the pi* resonance of formic acid

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)We report momentum transfer cross sections for elastic collisions of low-energy electrons with the HCOOH center dot center dot center dot(H2O)(n) complexes, with n = 1, 2, in liquid phase. The scattering cross sections were computed using the Schwinger multichannel method with pseudopotentials in the static-exchange and static-exchange plus polarization approximations, for energies ranging from 0.5 eV to 6 eV. We considered ten different structures of HCOOH center dot center dot center dot H2O and six structures of HCOOH center dot center dot center dot(H2O)(2) which were generated using classical Monte Carlo simulations of formic acid in aqueous solution at normal conditions of temperature and pressure. The aim of this work is to investigate the influence of microsolvation on the pi* shape resonance of formic acid. Previous theoretical and experimental studies reported a pi* shape resonance for HCOOH at around 1.9 eV. This resonance can be either more stable or less stable in comparison to the isolated molecule depending on the complex structure and the water role played in the hydrogen bond interaction. This behavior is explained in terms of (i) the polarization of the formic acid molecule due to the water molecules and (ii) the net charge of the solute. The proton donor or acceptor character of the water molecules in the hydrogen bond is important for understanding the stabilization versus destabilization of the pi* resonances in the complexes. Our results indicate that the surrounding water molecules may affect the lifetime of the pi* resonance and hence the processes driven by this anion state, such as the dissociative electron attachment. (C) 2013 AIP Publishing LLC.13817Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FINEP (under project CT-Infra)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Expansão dos cursos de Graduação em Enfermagem e mercado de trabalho: reproduzindo desigualdades?

O objetivo do estudo foi analisar a relação entre a expansão dos cursos de graduação de enfermagem e o mercado de trabalho dos enfermeiros em Minas Gerais. Estudo descritivo-exploratório de abordagem quantitativa, que utilizou fontes de dados secundários sobre os cursos de Graduação em Enfermagem, número de profissionais ocupados, vínculos em estabelecimentos de saúde e empregos formais de enfermeiros no Estado. A evolução dos cursos de Graduação em Enfermagem revela sinais de declínio na procura e oferta nos anos recentes, que pode estar relacionado ao mercado de trabalho do enfermeiro. Este, por sua vez, é marcado por contradições expressas pelo quantitativo excedente de profissionais, em especial nas regiões menos desenvolvidas do Estado, bem como pela baixa proporção de enfermeiros para atender as necessidades de saúde da população. Visualiza-se que estes aspectos reproduzem desigualdades e carecem discussões quanto à regulação da formação e à criação de novos postos de trabalho