Filaments and ionized gas in the vicinity of 3C 244.1

We present results of Hubble Space Telescope observations of the radio galaxy 3C 244.1. The broad-band F702W (R) and F555W (V) images (WFPC2/PC) show an elliptical galaxy, and gaseous filaments and blobs surrounding it. In the narrowband ramp filter, dominated by [O III] λ5007, these filaments are bright and have the same morphology as the broadband images. To the south, the filaments have a cone-shaped structure, and the radio jet is located at the center of this cone. To the north of the galaxy, the structure is found near the nucleus of the galaxy within its elliptical profile. From the photometry, the two brighter structures seem to be extended narrow-line emission regions. A comparison with diagnostic line ratios shows that the observed emission is consistent with interactions between the expanding radio jet and the local denser medium.Facultad de Ciencias Astronómicas y Geofísica

Multiple Myeloma Includes Phenotypically Defined Subsets of Clonotypic CD20+ B Cells that Persist During Treatment with Rituximab

Potential progenitor B cell compartments in multiple myeloma (MM) are clinically important. MM B cells and some circulating MM plasma cells express CD20, predicting their clearance by treatment with anti-CD20. Here we describe two types of clonotypic CD20+ B cell in peripheral blood of myeloma patients, identified by their expression of CD19 and CD20 epitopes, their expression of CD45RA and their light scatter properties. Thus, the circulating component of the MM clone includes at least two distinct CD19+ CD20+ B cell compartments, as well as CD138+ CD20+ plasma cells. To determine whether either or both B cell subsets and the CD20+ plasma cell subset were depleted by anti-CD20 therapy, they were evaluated before, during and after treatment of patients with rituximab (anti-CD20), followed by quantifying B cell subsets over a 5 month period during and after treatment. Overall, all three types of circulating B lineage cells persist despite treatment with rituximab. The inability of rituximab to prolong survival in MM may result from this failure to deplete CD20+ B and plasma cells in MM

Procesamiento de imágenes astronómicas con el equipo HP-1000 de la FCAGLP

As the HP-1000 computer of the FCAGLP will next be out of service, after thirteen years of use in Astrophysics, we present a summary of the software that was developed in the last years for its use in digital data handling (spectra and 2-D images).Asociación Argentina de Astronomí

Un estudio comparativo de las galaxias activas NGC 3783 y NGC 7552

Se presenta un análisis multicolor (BVRI) basado en imágenes CCD de la galaxia Seyfert 1 NGC 3783 y de la galaxia "starburst" NGC 7752. La primera presenta una conspicua componente nuclear no térmica y brazos (jets?) anómalos perpendiculares a la barra. Parte del brillo parece originarse en scattering electrónico. NGC 7552 presenta estructuras peculiares (azules) a bajos niveles de brillo. Se sugiere que la interacción de esas estructuras con la barra de la galaxia produce formación estelar extendida y regiones H II gigantes.Asociación Argentina de Astronomí

Filaments and ionized gas in the vicinity of 3C 244.1

We present results of Hubble Space Telescope observations of the radio galaxy 3C 244.1. The broad-band F702W (R) and F555W (V) images (WFPC2/PC) show an elliptical galaxy, and gaseous filaments and blobs surrounding it. In the narrowband ramp filter, dominated by [O III] λ5007, these filaments are bright and have the same morphology as the broadband images. To the south, the filaments have a cone-shaped structure, and the radio jet is located at the center of this cone. To the north of the galaxy, the structure is found near the nucleus of the galaxy within its elliptical profile. From the photometry, the two brighter structures seem to be extended narrow-line emission regions. A comparison with diagnostic line ratios shows that the observed emission is consistent with interactions between the expanding radio jet and the local denser medium.Facultad de Ciencias Astronómicas y Geofísica

Estudio óptico de LMXBS con alta resolución temporal evidencia de flares no térmicos en MXB 1735-44

We present a search for ultrafast optical variability among some low-mass X-ray binaries (LMXBS) using MANIA complex (Multichannel Analisys of Nanosecond Intensity Alterations) attached to the 2.15 m telescope of CASLEO. Two flares of ∼ 0.25 sec in duration were recorded from the MXB 1735-44 X-ray burster. Brightness of the object increased 15-30 times during these flares, with very steep forward fronts (characteristic rising time being ∼ 0.05-0.06 sec), and displaying a fine structure in time-scale of 0.005-0.006 sec (confidence level > 95%). Brightness temperatures of these phases within the flares were more than 5x10⁷,10⁸ K, respectively, which can only be explained by non-thermal processes. These results are an evidence that in MXB 1735-44 there exist some departures from standard model of accretion onto compact objects.Asociación Argentina de Astronomí