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São José dos Campos, Brazil

Moises A.P.,University of Sao Paulo | Damineli A.,University of Sao Paulo | Figueredo E.,University of Sao Paulo | Blum R.D.,NOAO | And 2 more authors.
Monthly Notices of the Royal Astronomical Society

We present a near-infrared study of the stellar content of 35 Hii regions in the Galactic plane, 24 of which have been classified as giant Hii regions. We have selected these optically obscured star-forming regions from the catalogues of Russeil, Conti & Crowther and Bica et al. In this paper, we have used the near-infrared domain J-, H- and Ks-band colour images to visually inspect the sample. Also, we have used colour-colour and colour-magnitude diagrams to indicate ionizing star candidates, as well as the presence of young stellar objects such as classical T Tauri stars and massive young stellar objects (MYSOs). We have obtained Spitzer Infrared Array Camera images for each region to help further characterize them. Spitzer and near-infrared morphology were used to place each cluster in an evolutionary phase of development. Spitzer photometry was also used to classify the MYSOs. A comparison of the main sequence in the colour-magnitude diagrams for each observed cluster was used to infer whether or not the cluster kinematic distance is consistent with brightnesses of the stellar sources. We find qualitative agreement for a dozen of the regions, but about half the regions have near-infrared photometry that suggests they may be closer than the kinematic distance. A significant fraction of these already have spectrophotometric parallaxes that support smaller distances. These discrepancies between kinematic and spectrophotometric distances are not a result of the spectrophotometric methodologies, as independent non-kinematic measurements are in agreement with the spectrophotometric results. For instance, the trigonometric parallaxes of star-forming regions were collected from the literature and show the same effect of smaller distances when compared to the kinematic results. In our sample of Hii regions, most of the clusters are evident in the near-infrared images. Finally, it is possible to distinguish among qualitative evolutionary stages for these objects. © 2010 The Authors Monthly Notices of the Royal Astronomical Society © 2010 RAS. Source

Pilling S.,and | Duarte E.S.,Grupo de Fisica e Astronomia | Domaracka A.,CNRS Center for Research on Ions, Materials and Photonics | Rothard H.,CNRS Center for Research on Ions, Materials and Photonics | And 2 more authors.
Physical Chemistry Chemical Physics

An experimental study of the interaction of highly charged, energetic ions (52 MeV 58Ni 13+ and 15.7 MeV 16O 5+) with mixed H 2O:C 18O 2 astrophysical ice analogs at two different temperatures is presented. This analysis aims to simulate the chemical and the physicochemical interactions induced by cosmic rays inside dense, cold astrophysical environments, such as molecular clouds or protostellar clouds as well at the surface of outer solar system bodies. The measurements were performed at the heavy ion accelerator GANIL (Grand Accelerateur National d'Ions Lourds) in Caen, France. The gas samples were deposited onto a CsI substrate at 13 K and 80 K. In situ analysis was performed by a Fourier transform infrared (FTIR) spectrometer at different fluences. Radiolysis yields of the produced species were quantified. The dissociation cross section at 13 K of both H 2O and CO 2 is about 3-4 times smaller when O ions are employed. The ice temperature seems to affect differently each species when the same projectile was employed. The formation cross section at 13 K of molecules such as C 18O, CO (with oxygen from water), and H 2O 2 increases when Ni ions are employed. The formation of organic compounds seems to be enhanced by the oxygen projectiles and at lower temperatures. In addition, because the organic production at 13 K is at least 4 times higher than the value at 80 K, we also expect that interstellar ices are more organic-rich than the surfaces of outer solar system bodies. © 2011 the Owner Societies. Source

von Atzingen D.A.N.C.,University of Sao Paulo | Gragnani A.,Unifesp | Veiga D.F.,Unifesp | Abla L.E.F.,Unifesp | And 2 more authors.
Acta Cirurgica Brasileira

Purpose: To determine the optimum concentration of a gel obtained from unripe banana (Musa sapientum) peel for wound treatment in rats. Methods: A randomized triple blind study was conducted with 40 Wistar rats, which were divided into 4 groups: CG, control group; G2%, 2% gel concentration group; G4%, 4% gel concentration group; and G10%, 10 % gel concentration group. The banana peel gel was applied daily, for 7 days, to a 4-cm 2 wound created on the back of each animal of all groups. After this period, the wounds were biopsied. Statistical analysis was carried out using the Kruskal-Wallis test complemented by the Student-Newman-Keuls test. Results: Macroscopic examination revealed that partial epithelialization occurred in all groups. Wound contraction was also observed in all groups and ranged from 1.38 to 1.57 mm in the study groups, and from 1.03 to 1.10 mm in the control group, with significant differences (p < 0.05) between the groups: CG and G10%, G2% and G4%, G2% and G10%. The interquartile deviation was smaller between the groups CG and G4%. Conclusion: The 4% gel obtained from unripe banana peel (G4%) resulted in better epithelialization of wounds healed by secondary intention compared with other gel concentrations. Source

And ! | Date: 2001-01-23


A method of producing volume renderings from magnetic resonance image data in real time with user interactivity. The method comprises collecting raw magnetic resonance image (MRI) data representative of shapes within an image volume; transferring the raw MRI data to a computer; and continuously producing volume renderings from the raw MRI data in real time with respect to the act of collecting raw MRI data representative of shapes within the image volume.

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