Avaliação dos métodos de propagação de algumas spondias agroindustriais.

A Embrapa Agroindústria Tropical vem desenvolvendo pesquisas sobre os métodos de propagação, visando ao aumento da germinação, clonagem de genótipos superiores para produção de mudas, domesticação e cultivo em escala comercial.bitstream/CNPAT-2010/11954/1/Ct-031.pd

Métodos de enxertia recomendados para a produção de mudas de cajazeira e de outras fruteiras do gênero spondias.

As principais especies do genero spondias que ocorrem no Nordeste brasileiro sao Spondias mombim (cajazeira) Spondias purpurea (cirigueleira) Spondias cytherea (cajananeira), Spondias tuberosa (umbuzeiro) Spondias ssp (umbu-cajazeira e umbugueleira.bitstream/item/33817/1/Ct-037.pd

Eta Carinae: Binarity Confirmed

We report the recovery of a spectroscopic event in eta Carinae in 1997/98 after a prediction by Damineli (1996). A true periodicity with P = 2020+-5 days (0.2% uncertainty) is obtained. The line intensities and the radial-velocity curve display a phase-locked behavior implying that the energy and dynamics of the event repeat from cycle to cycle. This rules out S Doradus oscillation or multiple shell ejection by an unstable star as the explanation of the spectroscopic events. A colliding-wind binary scenario is supported by our spectroscopic data and by X-ray observations. Although deviations from a simple case exist around periastron, intensive monitoring during the next event (mid 2003) will be crucial to the understanding of the system.Comment: 13 pages, accepted by ApJ Letters (January 2000

On the hydrogen neutral outflowing disks of B[e] supergiants

(abridged) B[e] supergiants are known to possess geometrically thick dusty disks. Disk-forming wind models have, however, been found to be insufficient in reproducing the observed dust emission. This problem arises due to the severe assumption that, as for classical Be stars, the near-infrared excess emission originates in the disk. Modeling of the free-free and free-bound emission therefore results in an upper limit for the disk mass loss rate, hampering dust condensation in the disk. We propose a revised scenario for the non-spherical winds of B[e] supergiants: a normal B-type line-driven polar wind and an outflowing disk-forming wind that is neutral in hydrogen at, or very close to the stellar surface. We concentrate on the pole-on seen LMC B[e] supergiant R126 and calculate the line luminosities of the optical [OI] emission lines with an outflowing disk scenario. In addition, we compute the free-free and free-bound emission from a line-driven polar wind and model the spectral energy distribution in the optical and near-infrared. Good fits to the [OI] line luminosities are achieved for an outflowing disk that is neutral in hydrogen right from the stellar surface. Neutral thereby means that hydrogen is ionized by less than 0.1%. Consequently, the free-free and free-bound emission cannot (dominantly) arise from the disk and cannot limit the disk mass loss rate. The hydrogen neutral outflowing disk scenario therefore provides an ideal environment for efficient dust formation. The spectral energy distribution in the optical and near-infrared range can be well fitted with the stellar continuum plus free-free and free-bound emission from the polar line-driven wind. Our modeling further delivers minimum values for \dot{M}(disk) > 2.5d-5 M_sun/yr and for the density contrast between equatorial and polar wind of ~10.Comment: 9 pages, 8 figures, accepted for publication in A&

The peculiar B-type supergiant HD327083

Coude spectroscopic data of a poorly-studied peculiar supergiant, HD327083, are presented. Halpha and Hbeta line profiles have been fitted employing a non-LTE code adequate for spherically expanding atmospheres. Line fits lead to estimates of physical parameters. These parameters suggest that HD327083 may be close to the Luminous Blue Variable phase but it is also possible that it could be a B[e] Supergiant.Comment: 4 pages, 4 figures, Accepted for publication in A&A Lette

The enigmatic B[e]-star Henize 2-90: The non-spherical mass loss history from an analysis of forbidden lines

(abridged) We study the optical spectrum of the exciting B[e] star Hen 2-90 based on new high-resolution observations that cover the innermost 2". Our investigation is splitted in two parts, a qualitative study of the presence of the numerous emission lines and the classification of their line profiles which indicate a circumstellar environment of high complexity, and a quantitative analysis of numerous forbidden lines, e.g. [OI], [OII], [OIII], [SII], [SIII], [ArIII], [ClII], [ClIII] and [NII]. We find a correlation between the different ionization states of the elements and the velocities derived from the line profiles: the highly ionized atoms have the highest outflow velocity while the neutral lines have the lowest outflow velocity. The recent HST image of Hen 2-90 reveals a bipolar, highly ionized region, a neutral disk-like structure and an intermediate region of moderate ionization. It seems that a non-spherical stellar wind model is a good option to explain the ionization and spatial distribution of the circumstellar material. We modelled the forbidden lines under the assumption of a non-spherically symmetric wind based on the HST image. We find that in order to fit the observed line luminosities, the mass flux, surface temperature, and terminal wind velocities need to be latitude dependent, which might be explained in terms of a rapidly rotating central star. A rotation speed of 75-80 % of the critical velocity has been derived. The total mass loss rate of the star was determined to be of order 3 10^{-5} M_sun/yr. Such a wind scenario and the fact that compared to solar abundances C, O, and N seem to be underabundant while S, Ar and Cl have solar abundances, might be explained in terms of a rapidly rotating post-AGB star.Comment: 16 pages, 13 figures, accepted for publication in A&A. Table 4 is included at the end of the paper. This table will only be available in the online version of the paper and will not appear in the printed versio

The Projected Rotational Velocity Distribution of a Sample of OB stars from a Calibration based on Synthetic He I lines

We derive projected rotational velocities (vsini) for a sample of 156 Galactic OB star members of 35 clusters, HII regions, and associations. The HeI lines at $\lambda\lambda$4026, 4388, and 4471A were analyzed in order to define a calibration of the synthetic HeI full-widths at half maximum versus stellar vsini. A grid of synthetic spectra of HeI line profiles was calculated in non-LTE using an extensive helium model atom and updated atomic data. The vsini's for all stars were derived using the He I FWHM calibrations but also, for those target stars with relatively sharp lines, vsini values were obtained from best fit synthetic spectra of up to 40 lines of CII, NII, OII, AlIII, MgII, SiIII, and SIII. This calibration is a useful and efficient tool for estimating the projected rotational velocities of O9-B5 main-sequence stars. The distribution of vsini for an unbiased sample of early B stars in the unbound association Cep OB2 is consistent with the distribution reported elsewhere for other unbound associations.Comment: Accepted for publication in The Astronomical Journa

Neutral material around the B[e] supergiant star LHA 115-S 65: An outflowing disk or a detached Keplerian rotating disk?

B[e] supergiants are surrounded by large amounts of hydrogen neutral material, traced by the emission in the optical [OI] lines. This neutral material is most plausibly located within their dense, cool circumstellar disks, which are formed from the (probably non-spherically symmetric) wind material released by the star. Neither the formation mechanism nor the resulting structure and internal kinematics of these disks (or disk-like outflows) are well known. However, rapid rotation, lifting the material from the equatorial surface region, seems to play a fundamental role. The B[e] supergiant LHA 115-S 65 (S65) in the SMC is one of the two most rapidly rotating B[e] stars known. Its almost edge-on orientation allows a detailed kinematical study of its optically thin forbidden emission lines. With a focus on the [OI] lines, we test the two plausible disk scenarios: the outflowing and the Keplerian rotating disk. Based on high- and low-resolution optical spectra, we investigate the density and temperature structure in those disk regions that are traced by the [OI] emission to constrain the disk sizes and mass fluxes needed to explain the observed [OI] line luminosities. In addition, we compute the emerging line profiles expected for either an outflowing disk or a Keplerian rotating disk, which can directly be compared to the observed profiles. Both disk scenarios deliver reasonably good fits to the line luminosities and profiles of the [OI] lines. Nevertheless, the Keplerian disk model seems to be the more realistic one, because it also agrees with the kinematics derived from the large number of additional lines in the spectrum. As additional support for the presence of a high-density, gaseous disk, the spectrum shows two very intense and clearly double-peaked [CaII] lines. We discuss a possible disk-formation mechanism, and similarities between S65 and the group of LBVs.Comment: 13 pages, 12 figures, accepted for publication in A&

Parâmetros fisiológicos e eritrograma de caprinos Canindé criados no semi-árido cearense.

A raça Canindé é considerada uma raça nativa do Brasil e possui animais adaptados às condições climáticas do semi-árido e alta prolificidade. Objetivou-se com este estudo determinar os parâmetros fisiológicos e o eritrograma, ao longo do ano (período chuvoso e seco), de caprinos Canindé criados no semi-árido cearense. O estudo foi realizado na Embrapa Caprinos com cinco machos e dez fêmeas da raça Canindé, com idade entre 1 ano e ½ a 3 anos e ½ e escore corporal entre 1,75 a 3,0. As coletas de sangue eram realizadas das 8 às 10 horas da manhã, nos meses de abril e setembro de 2007, totalizando 60 amostras, através de punção da veia jugular com tubo vacutainerÒ com anticoagulante EDTA. Antes e durante o experimento os animais foram avaliados quanto à condição de higidez, através de exame clínico geral. Os dados obtidos foram submetidos à análise estatística através do teste "t" de Student utilizando-se o cálculo da diferença mínima significativa ao nível de 5%. No exame clínico observou-se que os caprinos apresentavam comportamento ativo e as mucosas apresentavam coloração normal. Houve diferença estatística significativa quanto aos valores de freqüência cardíaca (FC) (P < 0,05), freqüência respiratória (FR) (P < 0,05), movimentos ruminais (MR) (P < 0,001), temperatura retal (TR) (P < 0,01), número de hemácias (He) (P < 0,05) e hemoglobina corpuscular média (CHCM) (P < 0,01) quando comparados entre os períodos seco e chuvoso. Os valores de hemoglobina (Hb) para fêmeas no período chuvoso e para os machos no período seco estão pouco abaixo da normalidade com relação aos dados médios para caprinos. Portanto, a raça Canindé não apresenta valores sangüíneos discrepantes em relação aos citados na literatura, apesar de apresentar elevação nas características adaptativas no período seco na região semi-árida em relação a outras regiões