Tumor cerebral: incidência, diagnóstico e tratamento

Relatório de estágio de licenciatura, Bioquímica, Faculdade de Ciências e Tecnologia da Universidade do Algarve, 2010O tumor cerebral é um tumor raro. A sua relevância incide no facto de pertencer aos tipos de tumores para os quais não existe cura, que provocam défices profundos nos doentes e cujos sintomas são muitas vezes negligenciados. Este estudo engloba doentes com diagnóstico de tumor cerebral maligno, internados no período de 1 de Junho de 2008 a 30 de Julho de 2010, no Hospital de Faro E.P.E.. Foram contabilizados 84 processos clínicos, porém apenas 52 destes puderam ser analisados. Destes 52 processos, 56% pertenciam ao sexo masculino sendo que a maior frequência foi encontrada na faixa etária dos 71 aos 75 anos. Apenas metade dos doentes realizou biopsia e o tipo de tumor cerebral maligno mais frequente foi o glioblastoma, contando com 32 diagnósticos, sendo que 81% da totalidade dos casos são tumores gliais. Somente 29% dos doentes ainda se encontram vivos até à data e o tempo de sobrevivência foi de apenas 1 mês para 24% dos doentes falecidos após diagnóstico de tumor cerebral maligno. Do total de diagnósticos analisados somente realizaram cirurgia 30 doentes, 18 fizeram radioterapia e 13 foram propostos a quimioterapia. Cefaleias, hemiparesia, convulsões, confusão, astenia, febre, afasia, paralisia facial, prostração, desorientação e vómitos, foram os sintomas constatados mais frequentemente.The brain tumor is a rare tumor. Its importance relies in the fact that it belongs to the tumor types for which there’s no cure and that causes profound deficits in patients, which symptoms are often, overlooked. This study includes patients whose malignant brain tumor diagnosis, was carried out from June 1st 2008 to July 30th 2010, in Hospital de Faro E.P.E.. 84 clinical cases were reported, but only 52 of these could be analysed. From these 52 cases, 56% were male and the highest frequency was found in the age range of 71 to 75 years. Only half of the patients performed biopsy and the malignant brain tumor glioblastoma was the most frequent, with 32 diagnoses, where 81% of all cases are glial tumors. Only 29% of patients are still alive so far and the survival time was only 1 month to 24% of deceased patients after diagnosis. In the total of diagnoses examined only 30 patients underwent surgery, 18 had radiotherapy and 13 were proposed to chemotherapy. Headache, hemiparesis, seizures, confusion, weakness, fever, aphasia, facial paralysis, prostration, disorientation and vomiting were the most observed symptoms

The optical-ultraviolet continuum of Seyfert 2 galaxies

This paper aims to understand the continuum of Seyfert 2 galaxies. By fitting the single galaxies in the sample of Heckman et al. (1995) with composite models (shock+ photoionization from the active center), we show that five main components characterize the SED of the continuum. Shocks play an important role since they produce a high temperature zone where soft X-rays are emitted. We show that in the optical-UV range, the slope of the NLR emission reproduces the observed values, and may be the main component of the featureless continuum. The presence of star forming regions cannot be excluded in the circumnuclear region of various Seyfert galaxies. An attempt is made to find their fingerprints in the observed AGN spectra. Finally, it is demonstrated that multi-cloud models are necessary to interpret the spectra of single objects, even in the global investigation of a sample of galaxies.Comment: 26 pages, LaTeX (including 5 Tables) + 17 PostScript figures. To appear in "The Astrophysical Journal

C, N, O Abundances in the Most Metal-Poor Damped Lyman alpha Systems

This study focuses on some of the most metal-poor damped Lyman alpha absorbers known in the spectra of high redshift QSOs, using new and archival observations obtained with UV-sensitive echelle spectrographs on the Keck and VLT telescopes. The weakness and simple velocity structure of the absorption lines in these systems allows us to measure the abundances of several elements, and in particular those of C, N, and O, a group that is difficult to study in DLAs of more typical metallicities. We find that when the oxygen abundance is less than about 1/100 of solar, the C/O ratio in high redshift DLAs and sub-DLAs matches that of halo stars of similar metallicity and shows higher values than expected from galactic chemical evolution models based on conventional stellar yields. Furthermore, there are indications that at these low metallicities the N/O ratio may also be above simple expectations and may exhibit a minimum value, as proposed by Centurion and her collaborators in 2003. Both results can be interpreted as evidence for enhanced production of C and N by massive stars in the first few episodes of star formation, in our Galaxy and in the distant proto-galaxies seen as QSO absorbers. The higher stellar yields implied may have an origin in stellar rotation which promotes mixing in the stars' interiors, as considered in some recent model calculations. We briefly discuss the relevance of these results to current ideas on the origin of metals in the intergalactic medium and the universality of the stellar initial mass function.Comment: 17 pages, 9 Figures, Accepted for publication in Monthly Notices of the Royal Astronomical Societ

Nutrição e adubação: conceitos e aplicações na formação de mudas de pimenta longa.

bitstream/item/61763/1/Oriental-Doc13.pd

Teores de N, P, K, Ca, Mg e S em gravioleiras cultivadas em solução nutritiva com omissão de macronutrientes.

Publicado também: FRAZÃO, D. A. C.; HOMMA, A. K. O; VIÉGAS, I. de J. M. (Ed.). Contribuição ao desenvolvimento da fruticultura na Amazônia. Belém, PA: Embrapa Amazônia Oriental, 2006. p. 503-508

Heavy element abundances in blue compact galaxies

We present high-quality ground-based spectroscopic observations of 54 supergiant H II regions in 50 low-metallicity blue compact galaxies with oxygen abundances 12 + log O/H between 7.1 and 8.3. We use the data to determine abundances for the elements N, O, Ne, S, Ar and Fe. We also analyze Hubble Space Telescope (HST) Faint Object Spectrograph archival spectra of 10 supergiant H II regions to derive C and Si abundances in a subsample of 7 BCGs. The main result of the present study is that none of the heavy element-to-oxygen abundance ratios studied here (C/O, N/O, Ne/O, Si/O, S/O, Ar/O, Fe/O) depend on oxygen abundance for BCGs with 12 + log O/H < 7.6 (Z < Zsun/20). This constancy implies that all these heavy elements have a primary origin and are produced by the same massive (M > 10Msun) stars responsible for O production. The dispersion of the C/O and N/O ratios in these galaxies is found to be remarkably small, being only +/-0.03 dex and +/-0.02 dex respectively. This very small dispersion is strong evidence against any time-delayed production of C and primary N in the lowest-metallicity BCGs (secondary N production is negligible at these low metallicities). The absence of a time-delayed production of C and N is consistent with the scenario that galaxies with 12 + log O/H < 7.6 are undergoing now their first burst of star formation, and that they are therefore young, with ages not exceeding 40 Myr. If very low metallicities BCGs are indeed young, this would argue against the commonly held belief that C and N are produced by intermediate-mass (3Msun < M < 9Msun) stars at very low metallicities, as these stars would not have yet completed their evolution in these lowest metallicity galaxies.Comment: 37 pages, 5 EPS figures, to appear in ApJ, February 199

Doses de nitrogênio, fósforo e potássio no desenvolvimento da seringueira (Hevea brasiliensis Muell. Arg.) em Latossolo Amarelo textura media - Tracuateua, PA.

Experimento foi conduzido, durante oito anos, no município de Bragança, na localidade de Tracuateua, com o objetivo de avaliar a influencia da adubação nitrogenada (sulfato de amônio), fosfatada (superfosfato triplo) e potássica (cloreto de potássio) no desenvolvimento da seringueira (Fx 3899). O delineamento foi de blocos ao acaso com duas repetições em arranjo fatorial 3 x 3 x 2 para NPK, com lastro uniforme de magnésio. O nitrogênio não proporcionou efeito positivo na altura das plantas e no desenvolvimento do tronco, enquanto que potássio e fosforo apresentaram respostas benéficas significativas

Efeitos da omissão de macro e micronutrientes no desenvolvimento de mudas de cupuaçuzeiro.

Publicado também: FRAZÃO, D. A. C.; HOMMA, A. K. O; VIÉGAS, I. de J. M. (Ed.). Contribuição ao desenvolvimento da fruticultura na Amazônia. Belém, PA: Embrapa Amazônia Oriental, 2006. p. 445-452

Sintomas visuais de deficiências de macronutrientes em plantas de curauá variedade roxo (Ananas erectifolius).

FERTBIO 2006

An Imaging and Spectroscopic Study of the z=3.38639 Damped Lyman Alpha System in Q0201+1120: Clues to Star Formation Rate at High Redshift

We present the results of a series of imaging and spectroscopic observations aimed at identifying and studying the galaxy responsible for the z = 3.38639 damped lya system in the z = 3.61 QSO Q0201+1120. We find that the DLA is part of a concentration of matter which includes at least four galaxies (probably many more) over linear comoving dimensions, greater than 5h^-1Mpc. The absorber may be a 0.7 L* galaxy at an impact parameter of 15 h^-1 kpc, but follow-up spectroscopy is still required for positive identification. The gas is turbulent, with many absorption components distributed over approximately 270 km/s and a large spin temperature, T_s greater than 4000K. The metallicity is relatively high for this redshift, Z(DLA) approximately 1/20 Z(solar). From consideration of the relative ratios of elements which have different nucleosynthetic timescales, it would appear that the last major episode of star formation in this DLA occurred at z greater than 4.3, more than approximately 500 Myr prior to the time when we observe it.Comment: Accepted for publication in Ap