73 research outputs found

    Through the magnifying glass: ALMA acute viewing of the intricate nebular architecture of OH231.8+4.2

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    We present continuum and molecular line emission ALMA observations of OH 231.8+4.2, a well studied bipolar nebula around an asymptotic giant branch (AGB) star. The high angular resolution (~0.2-0.3 arcsec) and sensitivity of our ALMA maps provide the most detailed and accurate description of the overall nebular structure and kinematics of this object to date. We have identified a number of outflow components previously unknown. Species studied in this work include 12CO, 13CO, CS, SO, SO2, OCS, SiO, SiS, H3O+, Na37Cl, and CH3OH. The molecules Na37Cl and CH3OH are first detections in OH 231.8+4.2, with CH3OH being also a first detection in an AGB star. Our ALMA maps bring to light the totally unexpected position of the mass-losing AGB star (QX Pup) relative to the large-scale outflow. QX Pup is enshrouded within a compact (<60 AU) parcel of dust and gas (clump S) in expansion (V~5-7 km/s) that is displaced by 0.6arcsec to the south of the dense equatorial region (or waist) where the bipolar lobes join. Our SiO maps disclose a compact bipolar outflow that emerges from QX Pup's vicinity. This outflow is oriented similarly to the large-scale nebula but the expansion velocities are about ten times lower (~35 km/s). We deduce short kinematical ages for the SiO outflow, ranging from ~50-80 yr, in regions within ~150 AU, to ~400-500 yr at the lobe tips (~3500 AU). Adjacent to the SiO outflow, we identify a small-scale hourglass-shaped structure (mini-hourglass) that is probably made of compressed ambient material formed as the SiO outflow penetrates the dense, central regions of the nebula. The lobes and the equatorial waist of the mini-hourglass are both radially expanding with a constant velocity gradient. The mini-waist is characterized by extremely low velocities, down to ~1 km/s at ~150 AU, which tentatively suggest the presence of a stable structure. (abridged

    Histoquímica de la fase progámica en Capsicum Pubescens

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    Capsicum pubescens Ruiz & Pav. (Solanaceae), conocido como ‘ají rocoto’, en Argentina se cultiva principalmente en el NO del territorio. En esta especie existe un amplio rango de variación en el nivel de compatibilidad, pero se desconocen los mecanismos que la regulan.Fil: Bo, M. L. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina.Fil: Bo, M. L. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Multidisciplinario de Biología Vegetal; Argentina.Fil: Cosa, M. T. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina.Fil: Carrizo García, C. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina.Fil: Carrizo García, C. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Multidisciplinario de Biología Vegetal; Argentina.Fil: Cosa, M. T. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Multidisciplinario de Biología Vegetal; Argentina.Ciencias de las Plantas, Botánic

    Filogenia molecular y tendencias evolutivas en Deprea (Solanaceae)

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    Fil: Deanna, R. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Multidisciplinario de Biología Vegetal; Argentina.Fil: Deanna, R. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Scaldaferro, M. A. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Multidisciplinario de Biología Vegetal; Argentina.Fil: Barboza, G. E. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Multidisciplinario de Biología Vegetal; Argentina.Fil: Barboza, G. E. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Carrizo García, C. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Multidisciplinario de Biología Vegetal; Argentina.Deprea Raf. y Larnax Miers fueron géneros controversiales en cuanto a su circunscripción y posición en la tribu Physalideae (Solanaceae). Análisis filogenéticos moleculares indican que estos géneros solo forman un clado monofilético cuando son combinados.http://www.botanicargentina.com.ar/boletin/SAB50Suplemento-JAB2015.pdfFil: Deanna, R. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Multidisciplinario de Biología Vegetal; Argentina.Fil: Deanna, R. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Scaldaferro, M. A. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Multidisciplinario de Biología Vegetal; Argentina.Fil: Barboza, G. E. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Multidisciplinario de Biología Vegetal; Argentina.Fil: Barboza, G. E. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Carrizo García, C. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Multidisciplinario de Biología Vegetal; Argentina.Otras Ciencias Naturales y Exacta

    Are Proto-Planetary Nebulae Shaped by a Binary? Results of a Long-Term Radial Velocity Study

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    The shaping of the nebula is currently one of the outstanding unsolved problems in planetary nebula (PN) research. Several mechanisms have been proposed, most of which require a binary companion. However, direct evidence for a binary companion is lacking in most PNs. We have addressed this problem by obtaining precise radial velocities of seven bright proto-planetary nebulae (PPNs), objects in transition from the asymptotic giant branch to the PN phases of stellar evolution. These have F-G spectral types and have the advantage over PNs of having more and sharper spectral lines, leading to better precision. Our observations were made in two observing intervals, 1991-1995 and 2007-2010, and we have included in our analysis some additional published and unpublished data. Only one of the PPNs, IRAS 22272+5435, shows a long-term variation that might tentatively be attributed to a binary companion, with P >> 22 years, and from this, limiting binary parameters are calculated. Selection effects are also discussed. These results set significant restrictions on the range of possible physical and orbital properties of any binary companions: they have periods greater than 25 years or masses of brown dwarfs or super-Jupiters. While not ruling out the binary hypothesis, it seems fair to say that these results do not support it.Comment: 14 pages, 3 figures, to appear Astrophys J, 734 (2011 June 10

    Shock excitation of the knots of Hen 3-1475

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    We present new optical STIS HST spectroscopic observations of the jets of the proto-planetary nebula Hen 3-1475. The excitation conditions of the knots of Hen 3-1475 are derived from the observed optical spectra, confirming that the knots are shock excited. The shocked spectra are qualitatively reproduced by simple ``3/2''D bow shock models. We present a set of bow shock models devoted to planetary nebulae, and discuss the effects of the pre-ionization conditions, the bow shock velocity, the bow shock shape and the chemical abundances on the predicted spectra. To explore the reliability of the ``3/2''D bow shock models, we also compare the observed spectra of other three proto-planetary nebulae (M 1-92, M 2-56 and CRL 618) to the predicted spectra.Comment: 13 pages. A&A (in press

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    Pheochromocytoma is a catecholamine-producing tumor originating from neuroendocrine cells located in the adrenal medulla. 85% is located in the adrenal medulla and the rest in the extra-adrenal chromaffin tissue (paraganglioma). It is one of the most frequent causes of secondary arterial hypertension. It is found in 0.1 to 1% of hypertensive patients of any age, with a peak from puberty to 40 years of age. In 85% of cases, they are single tumors without a family pattern. However, they can be multiple and familiar. The most frequent location is in the abdomen (95%). PRESENTATION OF THE CASE. A 51-year-old male patient with a history of hypertension, benign prostatic hyperplasia, and a former smoker. Medicated with Losartan 50mg, Carvedilol 12.5mg and Terazocine 5mg. Patient who consulted due to intense holocranial headache of 8 months of evolution associated with palpitations. On physical examination: BMI: 29.49 kg/m2, blood pressure 260/120 mmHg, HR 77 bpm, hyperphonetic heart sounds, no murmurs, good distal perfusion. The Electrocardiogram was normal. The laboratory evidenced: Plasma adrenaline: 14 pgr/ml (NV: 0-100 pgr/ml), plasma noradrenaline 410 pgr/ml (NV: 70-700 pgr/ml), plasma dopamine 121 pgr/ml (NV: 0-50 pgr/ml), urinary metanephrines: 33 µgr/24 h (NV: 44-261 µgr/24 hours), urinary normetanephrine 572 µgr/24 h (103-521 µgr/24 hours), vanillin mandelic acid 8.8 mgr/24 h (NV: 2.3-5.1 mgr/24 hours), urinary epinephrine 5.1 µgr/24 h (NV: 0.9-20 µgr/24 hours), urinary norepinephrine 162.2 µgr/24 h (NV: 15-80 µgr/24 hours) and urinary dopamine 238 µg/24 h (NV: 65-400 µg/24 hours). Interpreting itself as a producer of norepinephrine. Abdominal tomography with contrast showed a nodular image in the right adrenal gland of 49 x 49 x 33 mm, compatible with pheochromocytoma. Surgical treatment was performed whose biopsy confirmed the diagnosis. Subsequently, the doses of antihypertensive drugs were decreased. The diagnosis of pheochromocytoma requires a high clinical suspicion, catecholamine dosage and abdominal tomography. Surgical removal is essential, as it is one of the few forms of potentially curable hypertension (0.2%).El feocromocitoma es un tumor productor de catecolaminas originado en las células neuroendocrinas ubicadas en la medula suprarrenal. El 85% se localiza en la medula adrenal y el resto en el tejido cromafín extra adrenal (Paraganglioma). Es una de las causas más frecuente de hipertensión arterial secundaria. Se halla en el 0,1 a 1% de los hipertensos de cualquier edad, con un pico desde la pubertad hasta los 40 años. En el 85% de los casos son tumores únicos sin un patrón familiar. Sin embargo, pueden ser múltiples y familiares. La localización más frecuente es en abdomen (95%). PRESENTACION DEL CASO. Paciente masculino de 51 años, con antecedentes de HTA, hiperplasia benigna de próstata y ex tabaquista. Medicado con Losartan 50 mg, Carvedilol 12,5 mg y terazocina 5mg. Paciente que consultó por cefalea holocreaneana intensa de 8 meses de evolución asociada a palpitaciones. Al examen físico:&nbsp; IMC: 29,49 kg/m2, tensión arterial 260/120 mmHg, FC 77 lpm, ruidos cardíacos hiperfonéticos, sin soplos, buena perfusión distal. El Electrocardiograma fue normal. El laboratorio evidenció: Adrenalina plasmática: 14 pgr/ml (VN: 0-100 pgr/ml), noradrenalina plasmática 410 pgr/ml (VN: 70-700 pgr/ml), dopamina plasmática 121 pgr/ml (VN: 0-50 pgr/ml), metanefrinas urinarias: 33 µgr/24 hs (VN: 44-261 µgr/24 hs), normetanefrina urinaria 572 µgr/24 hs (103-521 µgr/24 hs), ácido vainillin mandélico 8.8 mgr/24 hs (VN: 2.3-5.1 mgr/24 hs), adrenalina urinaria 5.1 µgr/24 hs (VN: 0.9-20 µgr/24 hs), noradrenalina urinaria 162.2 µgr/24 hs (VN: 15-80 µgr/24 hs) y dopamina urinaria 238 µgr/24 hs (VN: 65-400 µgr/24 hs) . Interpretándose como productor de noradrenalina. La Tomografía de abdomen con contraste evidencio una imagen nodular en la glándula suprarrenal derecha de 49 x 49 x 33 mm, compatible con feocromocitoma. Se realizó tratamiento quirúrgico cuya biopsia confirmo el diagnóstico. Posteriormente, se disminuyeron las dosis de las drogas antihipertensivas. El diagnóstico del feocromocitoma requiere una alta sospecha clínica, el dosaje de catecolaminas y la tomografía de abdomen. La extirpación quirúrgica es fundamental, ya que constituye una de las pocas formas de hipertensión arterial potencialmente curables (0.2 %).

    The Maser-emitting Structure and Time Variability of the SiS Lines J =14-13 and 15-14 in IRC+10216

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    2 pags., 1 tab. -- Why Galaxies Care About AGB Stars: A Continuing Challenge through Cosmic Time Proceedings IAU Symposium No. 343, 2019 F. Kerschbaum, M. Groenewegen & H. Olofsson, eds.AGB stars are important contributors of processed matter to the ISM. However, the physical and chemical mechanisms involved in its ejection are still poorly known. This process is expected to have remarkable effects in the innermost envelope, where the dust grains are formed, the gas is accelerated, the chemistry is active, and the radiative excitation becomes important. A good tracer of this region in C-rich stars is SiS, an abundant refractory molecule that can display maser lines, very sensitive to changes in the physical conditions. We present high angular resolution interferometer observations (HPBW â‰30.″.25) of the v = 0 J = 14-13 and 15-14 SiS maser lines towards the archetypal AGB star IRC+10216, carried out with CARMA and ALMA to explore the inner 1> region around the central star. We also present an ambitious monitoring of these lines along one single pulsation period carried out with the IRAM 30 m telescope.The research leading to these results has received funding from the European Research Council under the European Union’s Seventh Framework Programme (FP7/2007-2013)/ ERC grant agreement n◦ 610256: NANOCOSMO

    Kinematics of the H2O masers at the centre of the PN K3-35

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    We have studied the kinematics traced by the water masers located at the centre of the planetary nebula (PN) K3-35, using data from previous Very Large Array (VLA) observations. An analysis of the spatial distribution and line-of-sight velocities of the maser spots allows us to identify typical patterns of a rotating and expanding ring in the position-velocity diagrams, according to our kinematical model. We find that the distribution of the masers is compatible with tracing a circular ring with a ~0.021 arcsec (~100 AU) radius, observed with an inclination angle with respect to the line of sight of 55 degrees. We derive expansion and rotation velocities of 1.4 and 3.1 km/s, respectively. The orientation of the ring projected on the plane of the sky, at PA 158 degrees, is almost orthogonal to the direction of the innermost region of the jet observed in K3-35, suggesting the presence of a disc or torus that may be related to the collimation of the outflow.Comment: 7 pages, 4 figures, 2 tables. Accepted by MNRA

    Multi-analytical characterization of an oncoid from a high altitude hypersaline lake using techniques employed in the Mars2020 and Rosalind Franklin missions on Mars

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    In this work, a geological sample of great astrobiological interest was studied through analytical techniques that are currently operating in situ on Mars and others that will operate in the near future. The sample analyzed consisted of an oncoid, which is a type of microbialite, collected in the Salar Carachi Pampa, Argentina. The main peculiarity of microbialites is that they are organo-sedimentary deposits formed by the in situ fixation and precipitation of calcium carbonate due to the growth and metabolic activities of microorganisms. For this reason, the Carachi Pampa oncoid was selected as a Martian analog for astrobiogeochemistry study. In this sense, the sample was characterized by means of the PIXL-like, SuperCam-like and SHERLOC-like instruments, which represent instruments on board the NASA Perseverance rover, and by means of RLS-like and MOMA-like instruments, which represent instruments on board the future ESA Rosalind Franklin rover. It was possible to verify that the most important conclusions and discoveries have been obtained from the combination of the results. Likewise, it was also shown that Perseverance rover-like remote-sensing instruments allowed a first detailed characterization of the biogeochemistry of the Martian surface. With this first characterization, areas of interest for in-depth analysis with Rosalind Franklin-like instruments could be identified. Therefore, from a first remote-sensing elemental identification (PIXL-like instrument), followed by a remote-sensing molecular characterization (SuperCam and SHERLOC-like instruments) and ending with an in-depth microscopic analysis (RLS and MOMA-like instruments), a wide variety of compounds were found. On the one hand, the expected minerals were carbonates, such as aragonite, calcite and high-magnesium calcite. On the other hand, unexpected compounds consisted of minerals related to the Martian/terrestrial surface (feldspars, pyroxenes, hematite) and organic compounds related to the past biological activity related to the oncoid (kerogen, lipid biomarkers and carotenes). Considering samples resembling microbialites have already been found on Mars and that one of the main objectives of the missions is to identify traces of past life, the study of microbialites is a potential way to find biosignatures protected from the inhospitable Martian environment. In addition, it should be noted that in this work, further conclusions have been obtained through the study of the results as a whole, which could also be carried out on Mars.This work is part of the common activities of the “Thematic Network SIGUE-Mars” (Grant RED2018-102600-T, funded by the Spanish AEI/MICINN/FEDER) who funded the coordination actions until the final editing of the manuscript. The costs of the research works were covered by two projects: (1) the Raman On Mars project: “Contribution of the Raman spectroscopy to the exploration of Mars and Martian Moons: ExoMars, Mars 2020 and MMX missions (RamOnMars)” (Grant No. PID2019-10744RB-C31, funded by the Spanish Agency for Research AEI/MICINN/FEDER); and (2) the PAMMAT project “Alteration processes in Mars and Moon Meteorites, and terrestrial Analogues at different environments: Mars2020, Rosalind Franklin and Returned Samples from Mars and Moon” (Grant No. PID2022-142750OB-I00, funded by the Spanish Agency for Research AEI/MICINN/FEDER). In addition, all the authors would like to thank Luis Ahumada and Nicolás Lopez for their assistance in the field trips and to the native communities of Antofalla, El Peñón, and Antofagasta de la Sierra. Finally, authors want to thank the Comunidad de Antofalla and the Secretaría de Medio Ambiente de la provincial de Catacarma for providing the exploration permits.Peer reviewe

    Microbial Biomarker Transition in High-Altitude Sinter Mounds From El Tatio (Chile) Through Different Stages of Hydrothermal Activity

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    Geothermal springs support microbial communities at elevated temperatures in an ecosystem with high preservation potential that makes them interesting analogs for early evolution of the biogeosphere. The El Tatio geysers field in the Atacama Desert has astrobiological relevance due to the unique occurrence of geothermal features with steep hydrothermal gradients in an otherwise high altitude, hyper-arid environment. We present here results of our multidisciplinary field and molecular study of biogeochemical evidence for habitability and preservation in silica sinter at El Tatio. We sampled three morphologically similar geyser mounds characterized by differences in water activity (i.e., episodic liquid water, steam, and inactive geyser lacking hydrothermal activity). Multiple approaches were employed to determine (past and present) biological signatures and dominant metabolism. Lipid biomarkers indicated relative abundance of thermophiles (dicarboxylic acids) and sulfate reducing bacteria (branched carboxylic acids) in the sinter collected from the liquid water mound; photosynthetic microorganisms such as cyanobacteria (alkanes and isoprenoids) in the steam sinter mound; and archaea (squalane and crocetane) as well as purple sulfur bacteria (cyclopropyl acids) in the dry sinter from the inactive geyser. The three sinter structures preserved biosignatures representative of primary (thermophilic) and secondary (including endoliths and environmental contaminants) microbial communities. Sequencing of environmental 16S rRNA genes and immuno-assays generally corroborated the lipid-based microbial identification. The multiplex immunoassays and the compound-specific isotopic analysis of carboxylic acids, alkanols, and alkanes indicated that the principal microbial pathway for carbon fixation in the three sinter mounds was through the Calvin cycle, with a relative larger contribution of the reductive acetyl-CoA pathway in the dry system. Other inferred metabolic traits varied from the liquid mound (iron and sulfur chemistry), to the steam mound (nitrogen cycle), to the dry mound (perchlorate reduction). The combined results revealed different stages of colonization that reflect differences in the lifetime of the mounds, where primary communities dominated the biosignatures preserved in sinters from the still active geysers (liquid and steam mounds), in contrast to the surviving metabolisms and microbial communities at the end of lifetime of the inactive geothermal mound
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