5,514 research outputs found

    Management of von Willebrand disease type 3 during pregnancy - 2 cases reports.

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    BACKGROUND: von Willebrand disease type 3, is an extremely rare condition. It can be severe and potentially life-threatening, particularly in pregnant women during labor and subsequently during early puerperium. Due to its rarity, there is no optimal treatment/management during pregnancy. CASE: We describe two cases of pregnant women with von Willebrand disease type 3, and its successful surveillance and treatment with Haemate P FVIII (human plasma-derived von Willebrand Factor-ristocetin co-factor associated with human coagulation factor VIII), during pregnancy, partum and puerperium. CONCLUSIONS: Daily prophylaxis with Haemate P FVIII in women with von Willebrand disease type 3, starting 2 hours before caesarean section until the 7th day of puerperium, associated with close analytical and clinical surveillance seems to be a safe clinical option

    Weak Galactic Halo--Fornax dSph Connection from RR Lyrae Stars

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    For the first time accurate pulsation properties of the ancient variable stars of the Fornax dwarf spheroidal galaxy (dSph) are discussed in the broad context of galaxy formation and evolution. Homogeneous multi-band BVIBVI optical photometry of spanning {\it twenty} years has allowed us to identify and characterize more than 1400 RR Lyrae stars (RRLs) in this galaxy. Roughly 70\% are new discoveries. We investigate the period-amplitude distribution and find that Fornax shows a lack of High Amplitude (A_V\gsim0.75 mag) Short Period fundamental-mode RRLs (P\lsim0.48 d, HASPs). These objects occur in stellar populations more metal-rich than [Fe/H]\sim-1.5 and they are common in the Galactic halo (Halo) and in globulars. This evidence suggests that old (age older than 10 Gyr) Fornax stars are relatively metal-poor. A detailed statistical analysis of the role of the present-day Fornax dSph in reproducing the Halo period distribution shows that it can account for only a few to 20\% of the Halo when combined with RRLs in massive dwarf galaxies (Sagittarius dSph, Large Magellanic Cloud). This finding indicates that Fornax-like systems played a minor role in building up the Halo when compared with massive dwarfs. We also discuss the occurrence of HASPs in connection with the luminosity and the early chemical composition of nearby dwarf galaxies. We find that, independently of their individual star formation histories, bright (M_V\lsim-13.5 mag) galaxies have HASPs, whereas faint ones (M_V\gsim-11 mag) do not. Interestingly enough, Fornax belongs to a luminosity range (--11<<MV<_V<--13.5 mag) in which the occurrence of HASPs appears to be correlated with the early star formation and chemical enrichment of the host galaxy.Comment: 7 pages, 5 figures, A&A, accepte

    Theoretical study of molecular electronic excitations and optical transitions of C60

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    We report results on ab initio calculations of excited states of the fullerene molecule by using configuration interaction (CI) approach with singly excited determinants (SCI). We have used both the experimental geometry and the one optimized by the density functional method and worked with basis sets at the cc-pVTZ and aug-cc-pVTZ level. Contrary to the early SCI semiempirical calculations, we find that two lowest 1T1u1Ag^1 T_{1u} \leftarrow {}^1 A_g electron optical lines are situated at relatively high energies of ~5.8 eV (214 nm) and ~6.3 eV (197 nm). These two lines originate from two 1T1u1Ag^1 T_{1u} \leftarrow {}^1 A_g transitions: from HOMO to (LUMO+1) (6hu3t1g6h_u \to 3t_{1g}) and from (HOMO--1) to LUMO (10hg7t1u10h_g \to 7t_{1u}). The lowest molecular excitation, which is the 13T2g1 ^3 T_{2g} level, is found at ~2.5 eV. Inclusion of doubly excited determinants (SDCI) leads only to minor corrections to this picture. We discuss possible assignment of absorption bands at energies smaller than 5.8 eV (or λ\lambda larger than 214 nm).Comment: 6 pages, 1 figure, 9 Table

    Polar distortions in hydrogen bonded organic ferroelectrics

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    Although ferroelectric compounds containing hydrogen bonds were among the first to be discovered, organic ferroelectrics are relatively rare. The discovery of high polarization at room temperature in croconic acid [Nature \textbf{463}, 789 (2010)] has led to a renewed interest in organic ferroelectrics. We present an ab-initio study of two ferroelectric organic molecular crystals, 1-cyclobutene-1,2-dicarboxylic acid (CBDC) and 2-phenylmalondialdehyde (PhMDA). By using a distortion-mode analysis we shed light on the microscopic mechanisms contributing to the polarization, which we find to be as large as 14.3 and 7.0\,μ\muC/cm2^{2} for CBDC and PhMDA respectively. These results suggest that it may be fruitful to search among known but poorly characterized organic compounds for organic ferroelectrics with enhanced polar properties suitable for device applications.Comment: Submitte

    Influência da adubação fosfatada e calagem sobre a absorção do zinco, em dois solos de Minas.

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    Two experiments were installed in the greenhouse to study the relationships between phosphate fertilization, liming and zinc fertilization. One experiment used a red latosol soil while the other used a dark brown acid soil. Hybrid corn AG 206 was used to plant both experiments. The data collected consisted of dry matter productions level of zinc in the leaves, stems and tootes of the corn as well as the P/Zn and Ca/Zn rations in the leaves. Phosphate fertilization and liming lowed the level of zinc in the corn leaves to a point equal to or lower than 14 ppm. These leves were below 80% of the maximum yields of the experiments. The application of 4,5 ppm of zinc to the soil was adequate to raise the level of zinc in the leaves above the critical level. It also increase the production was limited by a zinc deficiency. The phosphorus and zinc interaction, which ocurred primarily in the roots of the plant, reduced the translocation of zinc to the leaves. The interaction between liming and zinc ocurred prior to the absorption of zinc by the plant. It aprears that there are ratios between phosphorus and zinc between calcium and zinc in the leaves which are critical to good plant growth. The critical P/Zn ratio is betwee 300 and 470 and the critical Ca/Zn ratio between 455-640

    Configurational temperature control for atomic and molecular systems

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    A new configurational temperature thermostat suitable for molecules with holonomic constraints is derived. This thermostat has a simple set of motion equations, can generate the canonical ensemble in both position and momentum space, acts homogeneously through the spatial coordinates, and does not intrinsically violate the constraints. Our new configurational thermostat is closely related to the kinetic temperature Nosé-Hoover thermostat with feedback coupled to the position variables via a term proportional to the net molecular force. We validate the thermostat by comparing equilibrium static and dynamic quantities for a fluid of n-decane molecules under configurational and kinetic temperature control. Practical aspects concerning the implementation of the new thermostat in a molecular dynamics code and the potential applications are discussed

    Aplicação da metodologia definida pela OCDE para o cálculo de população urbana e rural nos municípios do Brasil

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    Não existe, à escala internacional, um consenso sobre a definição do conceito de “rural”, apesar de ser usado quer pelo senso comum quer pelos cientistas das ciências sociais. Com o objetivo de aplicar o critério de delimitação do rural da OCDE no território brasileiro, a presente comunicação utilizou dados do censo demográfico brasileiro de 2010, fornecidos pelo IBGE. Procurando seguir a tipologia da OCDE foi determinada a densidade demográfica de cada um dos 314.018 setores censitários e classificados como urbano ou rural. Com esses dados os 5.565 municípios foram qualificados como Região Predominantemente Rural; Região Intermediária e Região Predominantemente Urbana. Os resultados apontam para a maioria das cidades brasileiras como sendo consideradas regiões intermediárias
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