2,297 research outputs found

    A ringed pole-on outflow from DO Tauri revealed by ALMA

    Get PDF
    We present new ALMA Band 6 observations including the CO (2-1) line and 1.3 mmcontinuum emission from the surroundings of the young stellar object DO Tauri. TheALMA CO molecular data show three different series of rings at different radial ve-locities. These rings have radii around 220 au and 800 au. We make individual fits tothe rings and note that their centers are aligned with DO Tauri and its optical high-velocity jet. In addition, we notice that the velocity of these structures increases withthe separation from the young star. We discuss the data under the hypothesis that therings represent velocity cuts through three outflowing shells that are possibly drivenby a wide-angle wind, dragging the environment material along a direction close to theline of sight (i= 19◦). We estimate the dynamical ages, the mass, the momentum andthe energy of each individual outflow shell and those of the whole outflow. The resultsare in agreement with those found in outflows from Class II sources. We make a roughestimate for the size of the jet/wind launching region, which needs to be of.15 au.We report the physical characteristics of DO Tauri?s disk continuum emission (almostface-on and with a projected major axis in the north-south direction) and its velocitygradient orientation (north-south), indicative of disk rotation for a 1-2 Mcentral star.Finally we show an HST [SII] image of the optical jet and report a measurement of itsorientation in the plane of the sky.Fil: Fernandez Lopez, Manuel. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; ArgentinaFil: Zapata Gonzalez, Luis Alberto. Universidad Nacional Autonoma de Mexico. Instituto de Astronomia; MéxicoFil: Rodríguez, Luis F.. Universidad Nacional Autonoma de Mexico. Instituto de Astronomia; MéxicoFil: Vazzano, María Mercedes. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; ArgentinaFil: Guzman, Andrés E.. National Astronomical Observatory Of Japan; JapónFil: López, Rosario. Universidad Autónoma de Barcelona. Facultad de Física. Departamento Astronomía y Meteorología; Españ

    Quinoidization of regioregular oligo(THIENO[3,4-b]THIOPHENE)s

    Get PDF
    Caracterización de oligotiofenosUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

    Los ectoparásitos de los roedores sigmodontinos (Cricetidae) de La Rioja: resultados preliminares

    Get PDF
    El conocimiento sobre la fauna parasitaria es escasa o nula en muchas regiones de Argentina siendo La Rioja una de las provincias con menos registros, debido a los escasos muestreos de roedores sigmodontinos. El objetivo de este trabajo es reportar nuevos hospedadores y nuevas localidades geográficas para sifonápteros y ácaros parásitos de roedores sigmodontinos de la provincia de La Rioja. Las siguientes nuevas asociaciones fueron identificadas: Andalgalomys olrogi-Hectopsylla gracilis, Graomys chacoensis-Hectopsylla gracilis y Oligoryzomys cf. longicaudatus-Laelaps paulistanensis. Para la provincia se citan por primera vez Hectopsylla gracilis y las tres especies de ácaros registradas; y se da a conocer por primera vez un sifonáptero parásito para A. olrogi.In many regions of Argentina the knowledge of parasitic fauna is scarce or null; being the La Rioja one of the provinces with less record, due to scarce survey of sigmodontine rodents. In this paper, we report new hosts and new localities for fleas and mites parasites of sigmodontine rodents of La Rioja Province. The following new associations were identified: Andalgalomys olrogi-Hectopsylla gracilis; Graomys chacoensis-Hectopsylla gracilis; and Oligoryzomys cf. longicaudatus-Laelaps paulistanensis. Hectopsylla gracilis and the three recorded mites are reported of the first time from La Rioja Province and for the first time a flea on A. olrogi is cited.Fil: Lopez Berrizbeitia, M. F.. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales E Instituto Miguel Lillo. Programa de Investigación de Biodiversidad Argentina; Argentina. Programa de Conservación de los Murciélagos de Argentina; ArgentinaFil: Lareschi, Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Estudios Parasitológicos y de Vectores (i); ArgentinaFil: Sánchez, Rocío Tatiana. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales E Instituto Miguel Lillo. Programa de Investigación de Biodiversidad Argentina; Argentina. Programa de Conservación de los Murciélagos de Argentina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Regional de Investigaciones Cientificas y Transferencia Tecnológica de Anillaco; ArgentinaFil: Díaz, María Mónica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales E Instituto Miguel Lillo. Programa de Investigación de Biodiversidad Argentina; Argentina. Programa de Conservación de los Murciélagos de Argentina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán; Argentin

    Immunomodulation induced by synthetic peptides derived from Staphylococcus aureus protein A

    Get PDF
    Peptides from 10 to 22 amino acids containing sequences encompassed by Staphylococcus aureus protein A were synthesized. Some of these peptides, when present in cultures of lymphomononuclear cells from healthy donors or from cancer patients (melanoma, breast carcinoma, non-Hodgkin lymphoma and renal cell carcinoma) promoted: (i) changes in the phenotype of the lymphomononuclear population, (ii) stimulation of monocytes (release of IL-1 and TNF-alpha), and (iii) an increase in cytotoxicity against K562, Daudi and HT-29 cells. Isolated monocytes responded also to those peptides with a release of IL-1 and TNF alpha and an increase of cytotoxicity against HT-29 cells. It was found that the active peptides had the following structural pattern: a length of at least 15 amino-acid residues with a proline at position 6, valine, leucine, isoleucine, glycine, alanine or lysine at position 2, and glutamic or aspartic acid at position 11. Replacement of Pro at position 6 with any other residue turned the peptide inactive. Replacement of residues at positions 2 and 11 with amino-acid residues other than those required for activity resulted in compounds with a marked decrease in the immunomodulating properties described, or lacking these properties altogether

    A continuous method for arsenic removal from groundwater using hybrid biopolymer-iron-nanoaggregates: improvement through factorial designs

    Get PDF
    BACKGROUND: Due to a variety of toxicological problems, the presence of As(V) in aquifers is a significant concern. Sorption using chitosan doped with iron nanoaggregates results in a green and cheap methodology for its elimination. RESULTS: The hybrid sorbent was characterized by SEM, EDS, TGA, XRD, and FTIR spectroscopy. Its stability against pH and time was determined by ICP-MS, while conventional analytical techniques verified its Fe content. The sum of an individual As(V) removal capacity by chitosan and iron nanoaggregates was smaller than that of the hybrid sorbent, indicating the existence of synergy. CONCLUSION: This study demonstrates the great capacity of the hybrid sorbent to eliminate As(V) working with a continuous system (columns). The additional use of a factorial design allows for determining of optimal operating values to optimize two responses. In other words, in this multi-response system, column service time (tb) was minimized and, at the same time, it maximized the volumes of purified water obtained ([As(V)] <0.05 m L−1) using desirability function.Fil: Batistelli, Marianela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; ArgentinaFil: Perez Mora, Barbara Edith. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmaceuticas. Departamento de Química y Física; ArgentinaFil: Mangiameli, María Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmaceuticas. Departamento de Química y Física; ArgentinaFil: Mamana, Nadia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Exactas, Ingeniería y Agrimensura. Laboratorio de Materiales Cerámicos; ArgentinaFil: Lopez, Gerardo. NANOTEK S.A. Parque Tecnológico Litoral Centro; ArgentinaFil: Goddio, María F.. NANOTEK S.A. Parque Tecnológico Litoral Centro; ArgentinaFil: Bellú, Sebastián Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmaceuticas. Departamento de Química y Física; ArgentinaFil: González, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmaceuticas. Departamento de Química y Física; Argentin

    Efficient Removal of Heavy Metals from Aqueous Solutions Using a Bionanocomposite of Eggshell/Ag-Fe

    Get PDF
    Abstract: Eggshell and an easily synthesized bionanocomposite of eggshell with Ag-Fe nanoparticles demonstrated to be efficient adsorbent materials for the removal of lead, arsenic, and mercury from water. The natural material and the bionanocomposite were characterized by TEM and XRD. Ag-Fe nanoparticles vary from 1 to 100 nm in size. Equilibrium times of the adsorption systems were achieved between 4 and 8 h. The experimental adsorption data fitted the pseudo-second and Elovich models; therefore, the adsorption of heavy metals ions took place mainly by a chemical process. The adsorption capacity of eggshell in mg/g was 7.01 for As5+, 3.90 for Pb2+, and 1.51 for Hg2+, while the nanocomposite adsorption capacity was 17.7 for As5+, 27.8 for Pb2+ and 15.88 for Hg2+

    Distributed acoustic sensing for seismic activity monitoring

    Get PDF
    Continuous, real-time monitoring of surface seismic activity around the globe is of great interest for acquiring new insight into global tomography analyses and for recognition of seismic patterns leading to potentially hazardous situations. The already-existing telecommunication fiber optic network arises as an ideal solution for this application, owing to its ubiquity and the capacity of optical fibers to perform distributed, highly sensitive monitoring of vibrations at relatively low cost (ultra-high density of point sensors available with minimal deployment of new equipment). This perspective article discusses early approaches on the application of fiber-optic distributed acoustic sensors (DASs) for seismic activity monitoring. The benefits and potential impact of DAS technology in these kinds of applications are here illustrated with new experimental results on teleseism monitoring based on a specific approach: the so-called chirped-pulse DAS. This technology offers promising prospects for the field of seismic tomography due to its appealing properties in terms of simplicity, consistent sensitivity across sensing channels, and robustness. Furthermore, we also report on several signal processing techniques readily applicable to chirped-pulse DAS recordings for extracting relevant seismic information from ambient acoustic noise. The outcome presented here may serve as a foundation for a novel conception for ubiquitous seismic monitoring with minimal investment

    Versatile Graphene-Based Platform for Robust Nanobiohybrid Interfaces

    Get PDF
    Technologically useful and robust graphene-based interfaces for devices require the introduction of highly selective, stable, and covalently bonded functionalities on the graphene surface, whilst essentially retaining the electronic properties of the pristine layer. This work demonstrates that highly controlled, ultrahigh vacuum covalent chemical functionalization of graphene sheets with a thiol-terminated molecule provides a robust and tunable platform for the development of hybrid nanostructures in different environments. We employ this facile strategy to covalently couple two representative systems of broad interest: metal nanoparticles, via S-metal bonds, and thiol-modified DNA aptamers, via disulfide bridges. Both systems, which have been characterized by a multi-technique approach, remain firmly anchored to the graphene surface even after several washing cycles. Atomic force microscopy images demonstrate that the conjugated aptamer retains the functionality required to recognize a target protein. This methodology opens a new route to the integration of high-quality graphene layers into diverse technological platforms, including plasmonics, optoelectronics, or biosensing. With respect to the latter, the viability of a thiol-functionalized chemical vapor deposition graphene-based solution-gated field-effect transistor array was assessed

    Distributed acoustic sensing for seismic activity monitoring

    Get PDF
    Continuous, real-time monitoring of surface seismic activity around the globe is of great interest for acquiring new insight into global tomography analyses and for recognition of seismic patterns leading to potentially hazardous situations. The already-existing telecommunication fiber optic network arises as an ideal solution for this application, owing to its ubiquity and the capacity of optical fibers to perform distributed, highly sensitive monitoring of vibrations at relatively low cost (ultra-high density of point sensors available with minimal deployment of new equipment). This perspective article discusses early approaches on the application of fiber-optic distributed acoustic sensors (DASs) for seismic activity monitoring. The benefits and potential impact of DAS technology in these kinds of applications are here illustrated with new experimental results on teleseism monitoring based on a specific approach: the so-called chirped-pulse DAS. This technology offers promising prospects for the field of seismic tomography due to its appealing properties in terms of simplicity, consistent sensitivity across sensing channels, and robustness. Furthermore, we also report on several signal processing techniques readily applicable to chirped-pulse DAS recordings for extracting relevant seismic information from ambient acoustic noise. The outcome presented here may serve as a foundation for a novel conception for ubiquitous seismic monitoring with minimal investment
    corecore