Examinando por Autor "Moreno, E."

Mostrando 1 - 3 de 3

Acceso Abierto
Broad-band high-resolution rotational spectroscopy for laboratory astrophysics
(EDP Science, 2019-06-07) Cernicharo, J.; Gallego, J. D.; López Pérez, Jose A.; Tercero, Felix; Tanarro, I.; Beltrán, F.; De Vicente, P.; Lauwaet, K.; Alemán, Belén; Moreno, E.; Herrero, V. J.; Doménech, Jose Luis; Ramírez, S. I.; Bermúdez, Celina; Peláez, R. J.; Patino Esteban, Marina; López Fernández, Isaac; García Álvaro, Sonia; García Carreño, Pablo; Cabezas, Carlos; Malo, Inmaculada; Amils, R.; Sobrado, J. M.; Díez González, C.; Hernandéz, Jose M.; Tercero, B.; Santoro, G.; Martínez, L.; Castellanos, Marcelo; Vaquero Jiménez, B.; Pardo, Juan R.; Barbas, L.; López Fernández, Jose Antonio; Aja, B.; Leuther, A.; Martín-Gago, J. A.; Instituto Nacional de Técnica Aeroespacial (INTA); European Commission (EC); Agencia Estatal de Investigación (AEI)
We present a new experimental set-up devoted to the study of gas phase molecules and processes using broad-band high spectral resolution rotational spectroscopy. A reactor chamber is equipped with radio receivers similar to those used by radio astronomers to search for molecular emission in space. The whole range of the Q (31.5–50 GHz) and W bands (72–116.5 GHz) is available for rotational spectroscopy observations. The receivers are equipped with 16 × 2.5 GHz fast Fourier transform spectrometers with a spectral resolution of 38.14 kHz allowing the simultaneous observation of the complete Q band and one-third of the W band. The whole W band can be observed in three settings in which the Q band is always observed. Species such as CH3CN, OCS, and SO2 are detected, together with many of their isotopologues and vibrationally excited states, in very short observing times. The system permits automatic overnight observations, and integration times as long as 2.4 × 105 s have been reached. The chamber is equipped with a radiofrequency source to produce cold plasmas, and with four ultraviolet lamps to study photochemical processes. Plasmas of CH4, N2, CH3CN, NH3, O2, and H2, among other species, have been generated and the molecular products easily identified by the rotational spectrum, and via mass spectrometry and optical spectroscopy. Finally, the rotational spectrum of the lowest energy conformer of CH3CH2NHCHO (N-ethylformamide), a molecule previously characterized in microwave rotational spectroscopy, has been measured up to 116.5 GHz, allowing the accurate determination of its rotational and distortion constants and its search in space.
Acceso Abierto
Population Disequilibrium as Promoter of Adaptive Explorations in Hepatitis C Virus
(Multidisciplinary Digital Publishing Institute (MDPI), 2021-04-03) García Crespo, Carlos; Gallego, Isabel; Eugenia Soria, M.; Isabel de Ávila, A.; Martínez González, B.; Vázquez Sirvent, L.; Lobo Vega, Rebeca; Moreno, E.; Gómez, Jordi; Briones, C.; Gregori, Josep; Quer, J.; Domingo, Esteban; Perales, C.; Banco Santander; Fundación Ramón Areces; Instituto de Salud Carlos III (ISCIII); Agencia Estatal de Investigación (AEI); Ministerio de Economía y Competitividad (MINECO); García Crespo, C. [0000-0001-6561-5389]; Martínez González, B. [0000-0002-4482-5181]; Moreno, E. [0000-0002-2301-4558]; Briones, C. [0000-0003-2213-8353]; Quer, J. [0000-0003-0014-084X]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Replication of RNA viruses is characterized by exploration of sequence space which facilitates their adaptation to changing environments. It is generally accepted that such exploration takes place mainly in response to positive selection, and that further diversification is boosted by modifications of virus population size, particularly bottleneck events. Our recent results with hepatitis C virus (HCV) have shown that the expansion in sequence space of a viral clone continues despite prolonged replication in a stable cell culture environment. Diagnosis of the expansion was based on the quantification of diversity indices, the occurrence of intra-population mutational waves (variations in mutant frequencies), and greater individual residue variations in mutant spectra than those anticipated from sequence alignments in data banks. In the present report, we review our previous results, and show additionally that mutational waves in amplicons from the NS5A-NS5B-coding region are equally prominent during HCV passage in the absence or presence of the mutagenic nucleotide analogues favipiravir or ribavirin. In addition, by extending our previous analysis to amplicons of the NS3- and NS5A-coding region, we provide further evidence of the incongruence between amino acid conservation scores in mutant spectra from infected patients and in the Los Alamos National Laboratory HCV data banks. We hypothesize that these observations have as a common origin a permanent state of HCV population disequilibrium even upon extensive viral replication in the absence of external selective constraints or changes in population size. Such a persistent disequilibrium—revealed by the changing composition of the mutant spectrum—may facilitate finding alternative mutational pathways for HCV antiviral resistance. The possible significance of our model for other genetically variable viruses is discussed
Acceso Abierto
Using radio astronomical receivers for molecular spectroscopic characterization in astrochemical laboratory simulations: A proof of concept
(EDP Science, 2017-12-22) Tanarro, I.; Alemán, Belén; De Vicente, P.; Gallego, J. D.; Pardo, Juan R.; Santoro, G.; Lauwaet, K.; Tercero, Felix; Díaz Pulido, A.; Moreno, E.; Agúndez, Marcelino; Goicoechea, J. R.; Sobrado, J. M.; López, J. A.; Martínez, L.; Doménech, Jose Luis; Herrero, V. J.; Hernández, J. M.; Peláez, R. J.; López Pérez, Jose A.; Gómez González, J.; Alonso, J. L.; Jiménez, Elena; Teyssier, D.; Makasheva, Kremena; Castellanos, Marcelo; Joblin, C.; Martín Gago, J. A.; Cernicharo, J.; Ministerio de Economía y Competitividad (MINECO)
We present a proof of concept on the coupling of radio astronomical receivers and spectrometers with chemical reactors and the performances of the resulting setup for spectroscopy and chemical simulations in laboratory astrophysics. Several experiments including cold plasma generation and UV photochemistry were performed in a 40 cm long gas cell placed in the beam path of the Aries 40 m radio telescope receivers operating in the 41–49 GHz frequency range interfaced with fast Fourier transform spectrometers providing 2 GHz bandwidth and 38 kHz resolution. The impedance matching of the cell windows has been studied using different materials. The choice of the material and its thickness was critical to obtain a sensitivity identical to that of standard radio astronomical observations. Spectroscopic signals arising from very low partial pressures of CH3OH, CH3CH2OH, HCOOH, OCS, CS, SO2 (<10-3 mbar) were detected in a few seconds. Fast data acquisition was achieved allowing for kinetic measurements in fragmentation experiments using electron impact or UV irradiation. Time evolution of chemical reactions involving OCS, O2 and CS2 was also observed demonstrating that reactive species, such as CS, can be maintained with high abundance in the gas phase during these experiments.