Kinematics and stellar populations in active galaxies: the LINER NGC 4579 (M58)

This is an electronic version of an article published in Astronomy and Astrophysics. Palacios, J., García-Vargas, M.L., Diaz, A., Terlevich, R. and E. Terlevich. Kinematics and stellar populations in active galaxies: the LINER NGC 4579 (M58). Astronomy and Astrophysics 323 (1997): 749-76

Errores conceptuales institucionalizados en Matemáticas

A raíz de las reflexiones que surgen del análisis del actual Modelo Curricular de la Universidad de Sonora, donde el estudiante ocupa un lugar activo y protagónico en la construcción de su conocimiento y del momento de reflexión y análisis que propicia el inicio de la transición hacia un nuevo modelo curricular basado en Competencias, siendo insistente ambos en el uso de las nuevas TIC’s en los procesos de enseñanza y aprendizaje, en lo que a matemáticas se refiere, es oportuno hacer algunos señalamientos en relación, tanto en los aspectos metodológicos (el cómo enseñar), como en la precisión de los contenidos disciplinares a estudiar (el qué enseñar). En este artículo se hace un análisis parcial de estos aspectos, ejemplificándolo con uno de los conceptos fundamentales en matemáticas, desde el nivel básico hasta el superior y cómo algunos textos y más de un tipo de software matemático muy reconocidos, propician errores en la comprensión del mencionado concepto

A comprehensive study of reported high metallicity giant HII regions. I. Detailed abundance analysis

We present long-slit observations in the optical and near infrared of fourteen HII regions in the spiral galaxies: NGC 628, NGC 925, NGC 1232 and NGC 1637, all of them reported to have solar or oversolar abundances according to empirical calibrations. For seven of the observed regions, ion-weighted temperatures from optical forbidden auroral to nebular line ratios have been obtained and for six of them, the oxygen abundances derived by standard methods turn out to be significantly lower than solar. The other one, named CDT1 in NGC 1232, shows an oxygen abundance of 12+log(O/H) = 8.95+-0.20 and constitutes, to the best of our knowledge, the first high metallicity HII region for which accurate line temperatures, and hence elemental abundances, have been derived. For the rest of the regions no line temperature measurements could be made and the metallicity has been determined by means of both detailed photoionisation modelling and the sulphur abundance parameter S_23. Only one of these regions shows values of O_23 and S_23 implying a solar or oversolar metallicity. According to our analysis, only two of the observed regions can therefore be considered as of high metallicity. The two of them fit the trends previously found in other high metallicity HII regions, i.e. N/O and S/O abundance ratios seem to be higher and lower than solar respectively.Comment: Accepted for publication by MNRA

The stellar content of giant H II regions in NGC 7714

This is an electronic version of an article published in The Astrophysical Journal. García-Vargas, M.L., González-Delgado, R.M., Pérez, E., Alloin, D., Díaz, A. and E. Terlevich. The stellar content of giant H II regions in NGC 7714. The Astrophysical Journal 478 (1997): 112-12

Granuloma micótico nasal bovino

A case of mycotic bovine nasal granuloma in a 10 year-old Jersey cow, produced by Drechslera halodes is presented. Histopathological sections showed abundant hyaline and pigmented extra and intracellular fungal structures together with a polymorphic cellular granuloma formed by neutrophils, lymphocytes, plasmocytes, histiocytes and giant cells of the Langhans type. It is the first case of mycotic bovine nasal granuloma recognized in Uruguay although this disease seems to be frequent according to the opinion of veterinarian specialists. Another similar clinical case also in a Jersey cow from the same dairy house with an intense cellular infiltrate rich in eosinophils without granulomatous image, together with extracellular hyaline and fuliginous fungal forms, is also referred for comparative purposes. Geotrichum sp. was isolated. The need of an early diagnosis and treatment of the disease is stressed.É apresentado caso de granuloma micótico nasal bovino, em vaca Jersey, com 10 anos de idade, produzido por Drechslera halodes. Cortes histopatológicos mostraram abundantes estruturas fúngicas hialinas e pigmentadas extra e intracelulares junto com granuloma polimorfo celular formado por neutrófilos, linfócitos, plasmócitos, histiócitos e células gigantes de Langhans. É o primeiro caso de granuloma micótico nasal bovino diagnosticado no Uruguai embora esta doença pareça ser freqüente de acordo com a opinião de veterinários especializados. Outro caso clínico semelhante, também em vaca Jersey da mesma fazenda de criação de gado leiteiro, com intenso infiltrado celular rico em eosinófilos, sem imagem granulomatosa, junto com formas fúngicas fuliginosas hialinas extra celulares é também relatado para fins de comparação. Geotrichum sp. foi isolado. A necessidade de diagnóstico precoce e tratamento da doença é enfatizada

Chemical Abundances and Ionizing Clusters of HII Regions in the LINER Galaxy NGC 4258

We present long-slit observations in the optical and near infrared of eight HII regions in the spiral galaxy NGC 4258. Six of the observed regions are located in the SE inner spiral arms and the other two are isolated in the northern outer arms. A detailed analysis of the physical conditions of the gas has been performed. For two of the regions, an electron temperature has been derived from the [SIII] 6312 A line. For the rest, an empirical calibration based on the red and near infrared sulphur lines has been used. The oxygen abundances derived by both methods are found to be significantly lower (by a factor of two) than previously derived by using empirical calibrations based on the optical oxygen lines. In the brightest region, 74C, the observation of a prominent feature due to Wolf-Rayet stars provides an excellent constraint over some properties of the ionizing clusters. In the light of the current evolutionary synthesis models, no consistent solution is found to explain at the same time both the WR feature characteristics and the emission line spectrum of this region. In principle, the presence of WR stars could lead to large temperature fluctuations and also to a hardening of the ionizing radiation. None of these effects are found in region 74C for which the electron temperatures found from the [SIII] 6312A and the Paschen discontinuity at 8200A are equal within the errors and the effective temperature of the ionizing radiation is estimated at around 35,300K. Both more observations of confirmed high metallicity regions and a finer metallicity grid for the evolutionary synthesis models are needed in order to understand the ionizing populations of HII regions.Comment: 16 pages, 16 figures. To appear in MNRA

A comprehensive study of reported high metallicity giant HII regions. II. Ionising stellar populations

The ionising stellar populations of eleven HII regions in the spiral galaxies: NGC628, NGC925, NGC1232 and NGC1637, all of them reported to have solar or oversolar abundances according to empirical calibrations, have been analysed using stellar population synthesis models. Four of the observed regions in the sample, show features which indicate the presence of a population of Wolf-Rayet (WR) stars with ages between 2.3 and 4.1 Myr. This population is sufficient to explain the emission line spectrum of the low metallicity region H13 in NGC628. This is not the case for the rest of the regions for which a second ionising population is required to simultaneously reproduce both the WR features and the emission line spectrum. For two of the regions showing WR features, no consistent solution is found, since the population containing WR stars produces a spectral energy distribution which is too hard to explain the emission of the gas. Several solutions are proposed to solve this problem.Comment: 34 pages, 10 figures, accepted for publication in MNRA

The circumnuclear environment of the peculiar galaxy NGC 3310

Gas and star velocity dispersions have been derived for eight circumnuclear star-forming regions (CNSFRs) and the nucleus of the spiral galaxy NGC3310 using high resolution spectroscopy in the blue and far red. Stellar velocity dispersions have been obtained from the CaII triplet in the near-IR, using cross-correlation techniques, while gas velocity dispersions have been measured by Gaussian fits to the Hb 4861A and [OIII]5007A emission lines. The CNSFRs stellar velocity dispersions range from 31 to 73 km/s. These values, together with the sizes measured on archival HST images, yield upper limits to the dynamical masses for the individual star clusters between 1.8 and 7.1 x 10$^6$ M$_\odot$, for the whole CNSFR between 2 x 10$^7$ and 1.4 x 10$^8$ M$_\odot$, and 5.3 x 10$^7$ M$_\odot$ for the nucleus inside the inner 14.2 pc. The masses of the ionizing stellar population responsible for the HII region gaseous emission have been derived from their published Ha luminosities and are found to be between 8.7 x 10$^5$ and 2.1 x 10$^6$ M$_\odot$ for the star-forming regions, and 2.1 x 10$^5$ M$_\odot$ for the galaxy nucleus; they therefore constitute between 1 and 7 per cent of the total dynamical mass. The ionized gas kinematics is complex; two different kinematical components seem to be present as evidenced by different line widths and Doppler shifts.Comment: 24 pages, accepted by MNRA

Equivalencia terapéutica entre IOR® EPOCIM y EPO sin albúmina en pacientes con insuficiencia renal crónica en hemodiálisis

Ensayo Clínico Fase II-III, controlado, monocéntrico, a doble ciegas y aleatorizado, para evaluar la eficacia y seguridad del tratamiento con EPO Sin/Albúmina con un nuevo estabilizante y determinar la equivalencia terapéutica de esta formulación con el ior® EPOCIM, en enfermos hemodializados. Se incluyeron 60 pacientes, en hemodiálisis iterada 3 veces por semana, Kt/V mayor 1.2, los que mantuvieran niveles iguales o superiores de 10 g/l  de Hemoglobina  durante al menos 3 meses, tratados con ior® EPOCIM, divididos en 2 grupos, con 30 pacientes cada uno. El primero, recibió con EPO S/A la dosis habitual de Eritropoyetina y el segundo, con ior® EPOCIM, ambos por vía subcutánea en dosis 1:1 sin modificación de la dosis, evaluando la respuesta hematológica  (hemoglobina/ hematocrito) de ambos productos. Los grupos de tratamiento fueron homogéneos, según las variables analizadas: la edad media para el grupo EPO SA fue de 43.8 años, mientras para el grupo ior® EPOCIM  fue de 46.8 años;  la media del peso seco fue de 61.1 Kg vs. 60.4 Kg. La dosis de Eritropoyetina administrada solo fue variada en dependencia del cambio de peso del enfermo entre la dosis al inicio y al final de las 12 semanas: EPO S/A 7482.9 vs. 7485.4 UI/Kg/semanal y ior® EPOCIM 8045.3  vs. 8018.6 UI/Kg/semanal. Los resultados iniciales del hematocrito (35.9% vs. 36.6%) y de la hemoglobina (11.6 vs. 11.7 g/dl) mostraron que las medias del hematocrito, para ambos grupos, al final del estudio, tuvieron una diferencia inferior a 3 %  (33.8 vs. 34.5) y en la hemoglobina inferior a 1 g/dl (10.6 vs.  10.7),  con una disminución ligera al final del tratamiento similar para ambos grupos. Los eventos adversos detectados fueron: dolor en el sitio de la inyección (63 %), hipotensión (53.3 %), calambre (31.7 %) y cefaleas (15 %) atribuibles al proceder de hemodiálisis, con un perfil de seguridad propio de enfermos en hemodiálisis. No se observaron diferencias estadísticas significa-tivas entre los grupos (p=0.5938). Los resultados permiten sugerir la equiva-lencia terapéutica entre EPO S/A y EPOCIM. Se requiere la extensión en tiempo del fármaco; vigilancia de este nuevo producto para establecer sus efectos a largo plazo.  Palabras clave: anemia, eritropoyetina, hemodiálisis, insuficiencia renal crónica, ensayo clínico

El testimonio de Etty Hillesum desde el perfil de místico de ojos abiertos de Benjamín González Buelta

Two relatively contemporary mystics: Etty Hillesum and Benjamín GonzálezBuelta; two styles, two contexts, and a coincidence established from theirspiritual experiences, in deep connection with reality, in the midst of life andits challenges. Hillesum does not speak properly of the mystical experience,however, the personal existential process of her in the harsh context of thewar, led her to discover herself deeply inhabited. Her experience of God madeit possible for her to understand and manage the pain in the midst of war, aswell as the need to “make balm on the wounds” of her Jewish brothers. Etty isa wide-eyed mystic. Benjamín González Buelta has deepened his understandingof mysticism, describing and analyzing it from the experience of God in the LatinAmerican context. His reflection today allows one to read Etty Hillesum from theperspective of the wide-eyed mystic.Dos místicos relativamente contemporáneos: Etty Hillesum y Benjamín GonzálezBuelta; dos estilos, dos contextos y una coincidencia establecida desde susexperiencias espirituales, en profunda conexión con la realidad, en medio dela vida y sus desafíos. Hillesum no habla propiamente de la experiencia mística;sin embargo, su proceso personal existencial en el duro contexto de guerra lacondujo a descubrirse profundamente habitada. Su experiencia de Dios le hizoposible comprender y gestionar el dolor en medio de la guerra, así como lanecesidad de “hacerse bálsamo sobre las heridas” de sus hermanos judíos. Ettyes una mística de ojos abiertos. Benjamín González Buelta ha profundizado en lacomprensión de la mística, describiéndola y analizándola desde la experiencia deDios en el contexto latinoamericano. Su reflexión permite hoy leer a Etty Hillesumdesde la perspectiva del místico de ojos abiertos