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Taxanes for advanced non-small cell lung cancer (Protocol)
(Cochrane, 2018) Madrid, Eva; Barros Monge, Manuel J; Urrútia, Gerard; Roqué I Figuls, Marta; Pérez Bracchiglione, Javier; Vargas Peirano, Manuel; Loézar Hernández, Cristóbal Nicolás; Bonfill Cosp, Xavier
This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: To assess the effects of taxanes as part of a combined or single‐agent therapy versus other agents or best supportive care as first‐ or second‐line treatment for advanced non‐small cell lung cancer (NSCLC). A secondary objective is to assess different modes or schemes of administration of taxanes in patients with this disease.
Pre‐ and postnatal alcohol exposure delays, in female but not in male rats, the extinction of an auditory fear conditioned memory and increases alcohol consumption
(Wiley, 2019) Plaza, Wladimir; Gaschino, Felice; Gutiérrez, Camilo; Santibañez, Nicolás; Estay‐Olmos, Camila; Sotomayor‐Zárate, Ramón; De la Fuente‐Ortega, Erwin; Pautass, Ricardo M.; Haeger, Paola A.
Repeated exposure to alcohol increases retrieval of fear‐conditioned memories, which facilitates, among other factors, the emergence of post‐traumatic stress disorder (PTSD). Individuals with PTSD are more likely to develop alcohol and substance abuse related disorders. We assessed if prenatal and early postnatal alcohol exposure (PAE) increased the susceptibility to retain aversive memories and if this was associated with subsequent heightened alcohol consumption. Pregnant Sprague‐Dawley rats were exposed for 22 hr/day, throughout pregnancy and until postnatal Day 7 to a single bottle of sucralose ‐ sweetened 10% alcohol solution (PAE Group), or to a single bottle of tap water and sucralose (Control Group). Auditory fear conditioning (AFC) was performed in the adolescent offspring at postnatal Day 40. Freezing was measured during acquisition, retention and extinction phases, followed by 3 weeks of free choice alcohol intake. Female, but not male, PAE rats exhibited impaired extinction of the aversive memory, a finding associated with higher levels of 3‐4 Dihidroxyphenylacetic acid (DOPAC) in the nucleus accumbens and heightened alcohol intake, respect to controls. These findings suggest that PAE makes females more vulnerable to long‐term retention of aversive memories, which coexist with heightened alcohol intake. These findings are reminiscent of those of PTSD
Inclusión de salud basada en evidencia en carreras de la salud en Chile y el modelo integrado Metodología de la Investigación Científica-Medicina Basada en Evidencia en la Universidad de Valparaíso
(Elsevier, 2019) Papuzinski, Cristian; Loézar, Cristóbal; Carvajal, Natalia; Vargas, Manuel; Borgeat, Marjorie; Madrid, Eva; Pérez-Bracchiglione, Javier; Arancibia, Marcelo
Introducción: La salud basada en evidencia (SBE) integra el uso de la mejor evidencia, la experiencia clínica y los valores y preferencias del paciente para la toma de decisiones. Su incorporación en las carreras sanitarias de Chile es desconocida. Métodos: Se realizó un estudio de corte transversal para evaluar la incorporación de SBE en los programas de las carreras sanitarias en Chile hasta 2019. Se describe la integración del modelo Metodología de la Investigación Científica (MIC)-Medicina Basada en la Evidencia (MBE) en la Escuela de Medicina de la Universidad de Valparaíso. Resultados: Un total de 49 universidades imparten carreras sanitarias. Un 8,13% incorpora SBE como asignatura explícitamente. Todas incorporan asignaturas que potencialmente incluyen contenidos de SBE. Las carreras de Medicina y Enfermería son las que más incorporan SBE, pero solo una carrera de Medicina incluye SBE como asignatura por más de un semestre. El modelo integrado MIC/MBE (4 semestres), orientado en competencias y centrado en el alumno, involucra el diseno ̃ y ejecución de un protocolo de investigación, así como el análisis crítico de la mejor evidencia, integrado con los valores de los pacientes. Conclusión: La incorporación de SBE como asignatura es muy infrecuente en carreras sanitarias chilenas. Se enfatiza su inclusión transdisciplinaria como asignatura individual desde un modelo que integre la ensenanza ̃ de MIC, sobre todo en universidades estatales.
Development of Fixed Dose Combination Products Workshop Report: Considerations of Gastrointestinal Physiology and Overall Development Strategy
(Springer, 2019) Hens, Bart; Corsetti, Maura; Bermejo, Marival; Löbenberg, Raimar; González, Pablo M.; Mitra, V; Desai, Divyakant; Murthy Chilukuri, Dakshina; Aceituno, Alexis
The gastrointestinal (GI) tract is one of the most popular and used routes of drug product administration due to the convenience for better patient compliance and reduced costs to the patient compared to other routes. However, its complex nature poses a great challenge for formulation scientists when developing more complex dosage forms such as those combining two or more drugs. Fixed dose combination (FDC) products are two or more single active ingredients combined in a single dosage form. This formulation strategy represents a novel formulation which is as safe and effective compared to every mono-product separately. A complex drug product, to be dosed through a complex route, requires judicious considerations for formulation development. Additionally, it represents a challenge from a regulatory perspective at the time of demonstrating bioequivalence (BE) for generic versions of such drug products. This report gives the reader a summary of a 2-day short course that took place on the third and fourth of November at the Annual Association of Pharmaceutical Scientists (AAPS) meeting in 2018 at Washington, D.C. This manuscript will offer a comprehensive view of the most influential aspects of the GI physiology on the absorption of drugs and current techniques to help understand the fate of orally ingested drug products in the complex environment represented by the GI tract. Through case studies on FDC product development and regulatory issues, this manuscript will provide a great opportunity for readers to explore avenues for successfully developing FDC products and their generic versions.
Exocomets: A spectroscopic survey
(European Southern Observatory, 2020) Bayo, Amelia; Iglesias, Daniela Paz
Context. While exoplanets are now routinely detected, the detection of small bodies in extrasolar systems remains challenging. Since the discovery of sporadic events interpreted as exocomets (Falling Evaporating Bodies) around Pic in the early 80s, only 20 stars have been reported to host exocomet-like events. Aims. We aim to expand the sample of known exocomet-host stars, as well as to monitor the hot-gas environment around stars with previously known exocometary activity. Methods. We have obtained high-resolution optical spectra of a heterogeneous sample of 117 main-sequence stars in the spectral type range from B8 to G8. The data have been collected in 14 observing campaigns expanding over 2 years from both hemispheres. We have analysed the Ca ii K&H and Na i D lines in order to search for non-photospheric absorptions originated in the circumstellar environment, and for variable events that could be caused by outgassing of exocomet-like bodies. Results. We have detected non-photospheric absorptions towards 50% of the sample, attributing a circumstellar origin to half of the detections (i.e. 26% of the sample). Hot circumstellar gas is detected in the metallic lines inspected via narrow stable absorptions, and/or variable blue-/red-shifted absorption events. Such variable events were found in 18 stars in the Ca ii and/or Na i lines; 6 of them are reported in the context of this work for the first time. In some cases the variations we report in the Ca ii K line are similar to those observed in Pic. While we do not find a significant trend with the age or location of the stars, we do find that the probability of finding CS gas in stars with larger v sin i is higher. We also find a weak trend with the presence of near-infrared excess, and with anomalous ( Boo-like) abundances, but this would require confirmation by expanding the sample.
Cluster Difference Imaging Photometric Survey. II. TOI 837: A Young Validated Planet in IC 2602
(American Astronomical Society (Aas), 2020) Bouma, L. G.; Hartman, J. D.; Brahm, R.; Evans, P.; Collins, K. A.; Zhou, G.; Sarkis, P.; Quinn, S. N.; De Leon, J.; Livingston, J.; Bergmann, C.; Stassun, K. G.; Bhatti, W.; Winn, J. N.; Bakos, G. Á.; Abe, L.; Crouzet, N.; Dransfield, G.; Guillot, T.; Marie-Sainte, W.; Mékarnia, D.; Triaud, A. H. M. J.; Tinney, C. G.; Henning, T.; Espinoza, N.; Jordán, A.; Barbieri, M.; Nandakumar, S.; Trifonov, T.; Vines, J. I.; Vuckovic, M.; Ziegler, C.; Law, N.; Mann, A. W.; Ricker, G. R.; Vanderspek, R.; Seager, S.; Jenkins, J. M.; Burke, C. J.; Dragomir, D.; Levine, A. M.; Quintana, E. V.; Rodriguez, J. E.; Smith, J. C.; Wohler, B.
We report the discovery of TOI 837b and its validation as a transiting planet. We characterize the system using data from the NASA Transiting Exoplanet Survey Satellite mission, the ESA Gaia mission, ground-based photometry from El Sauce and ASTEP400, and spectroscopy from CHIRON, FEROS, and Veloce. We find that TOI 837 is a T = 9.9 mag G0/F9 dwarf in the southern open cluster IC 2602. The star and planet are therefore ${35}_{-5}^{+11}$ million years old. Combining the transit photometry with a prior on the stellar parameters derived from the cluster color–magnitude diagram, we find that the planet has an orbital period of $8.3\,\mathrm{days}$ and is slightly smaller than Jupiter (${R}_{{\rm{p}}}={0.77}_{-0.07}^{+0.09}\,{R}_{\mathrm{Jup}}$). From radial velocity monitoring, we limit ${M}_{{\rm{p}}}\sin i$ to less than 1.20 MJup (3σ). The transits either graze or nearly graze the stellar limb. Grazing transits are a cause for concern, as they are often indicative of astrophysical false-positive scenarios. Our follow-up data show that such scenarios are unlikely. Our combined multicolor photometry, high-resolution imaging, and radial velocities rule out hierarchical eclipsing binary scenarios. Background eclipsing binary scenarios, though limited by speckle imaging, remain a 0.2% possibility. TOI 837b is therefore a validated adolescent exoplanet. The planetary nature of the system can be confirmed or refuted through observations of the stellar obliquity and the planetary mass. Such observations may also improve our understanding of how the physical and orbital properties of exoplanets change in time.
The ALPINE-ALMA [CII] Survey: On the nature of an extremely obscured serendipitous galaxy
(Royal Astronomical Society, 2020) Ibar, Eduardo
We report the serendipitous discovery of a dust-obscured galaxy observed as part of the Atacama Large Millimeter Array (ALMA) Large Program to INvestigate [CII] at Early times (ALPINE). While this galaxy is detected both in line and continuum emissions in ALMA Band 7, it is completely dark in the observed optical/near-infrared bands and only shows a significant detection in the UltraVISTA Ks band. We discuss the nature of the observed ALMA line, that is [C II] at z ∼ 4.6 or high-J CO transitions at z ∼ 2.2. In the first case, we find a [CII]/FIR luminosity ratio of log(L[CII]/LFIR) ∼ −2.5, consistent with the average value for local star-forming galaxies (SFGs). In the second case instead, the source would lie at larger CO luminosities than those expected for local SFGs and high-z submillimetre galaxies. At both redshifts, we derive the star formation rate (SFR) from the ALMA continuum and the physical parameters of the galaxy, such as the stellar mass (M∗), by fitting its spectral energy distribution. Exploiting the results of this work, we believe that our source is a ‘main-sequence’, dusty SFG at z = 4.6 (i.e. [CII] emitter) with log(SFR/M. yr−1) ~ 1.4 and log(M*/M.) ∼ 9.9. As a support to this scenario our galaxy, if at this redshift, lies in a massive protocluster recently discovered at z ∼ 4.57, at only ∼1 proper Mpc from its centre. This work underlines the crucial role of the ALPINE survey in making a census of this class of objects, in order to unveil their contribution to the global SFR density at the end of the Reionization epoch
The ALPINE-ALMA [CII] Survey: A Triple Merger at z ~ 4.56
(Royal Astronomical Society, 2020) Ibar, Eduardo
We report the detection of [C II] λ158 μm emission from a system of three closely separated sources in the Cosmic Evolution Survey (COSMOS) field at z ∼ 4.56 , as part of the Atacama Large Millimeter/submillimeter Array (ALMA) Large Program to INvestigate C II at Early times (ALPINE). The two most luminous sources are closely associated, both spatially (1.6 arcsec ∼ 11 kpc) and in velocity (∼100 km s−1), while the third source is slightly more distant (2.8 arcsec ∼ 18 kpc, ∼300 km s−1). The second most luminous source features a slight velocity gradient, while no significant velocity gradient is seen in the other two sources. Using the observed [C II] luminosities, we derive a total log10(SFR[CII][M⊙yr−1])=2.8±0.2⁠, which may be split into contributions of 59, 31, and 10 per cent from the central, east, and west sources, respectively. Comparison of these [C II] detections to recent zoom-in cosmological simulations suggests an ongoing major merger. We are thus witnessing a system in a major phase of mass build-up by merging, including an ongoing major merger and an upcoming minor merger, which is expected to end up in a single massive galaxy by z ∼ 2.5.
Towards a multi-hazard analysis of infrastructure in a seismic coast subjected to climate change, with a focus on the Chilean coastline
(The University of Queensland, 2020) Winckler Grez, Patricio
The physics of some of the most relevant climatic and geophysical drivers affecting the Chilean coasts are reviewed. Some relevant figures about the country are introduced, and recent findings and research gaps on extreme waves, meteotsunamis, storm surge, sea level rise, earthquakes and tsunamis along the country are analyzed. A discussion on how to combine these phenomena to assess the level of flooding from a multi-hazard perspective is proposed, and a conceptual framework for the integration of short-term meteorological effects, long-term climate driven hazards and geophysical drivers into a multi-hazard analysis is discussed. Finally, the identification of gaps and future research is proposed. The multi-hazard, probabilistic and nonstationary design approach proposed herein, where uncertainty is at stake, can be extended to the design of coastal infrastructure, such as the stability of breakwaters, overtopping and forces on slender elements.
Individual Estimates of the Virial Factor in 10 Quasars: Implications on the Kinematics of the Broad-line Region
(The American Astronomical Society, 2020)
Assuming a gravitational origin for the Fe iiiλλ2039-2113 redshift and using microlensing based estimates of the size of the region emitting this feature, we obtain individual measurements of the virial factor, f, in 10 quasars. The average values for the Balmer lines, $\langle {f}_{{\rm{H}}\beta }\rangle =0.43\pm 0.20$ and $\langle {f}_{{\rm{H}}\alpha }\rangle =0.50\pm 0.24$, are in good agreement with the results of previous studies for objects with lines of comparable widths. In the case of Mg ii, consistent results, ${f}_{\mathrm{Mg}{\rm{II}}}\sim 0.44$, can be also obtained accepting a reasonable scaling for the size of the emitting region. The modeling of the cumulative histograms of individual measurements, CDF(f), indicates a relatively high value for the ratio between isotropic and cylindrical motions, $a\sim 0.4\mbox{--}0.7$. On the contrary, we find very large values of the virial factor associated to the Fe iiiλλ2039-2113 blend, ${f}_{\mathrm{Fe}{\rm{III}}}=14.3\pm 2.4$, which can be explained if this feature arises from a flattened nearly face-on structure, similar to the accretion disk.
NaCo polarimetric observations of Sz 91 transitional disc: a remarkable case of dust filtering
(Royal Astronomical Society, 2020) Mauco, Karina; Olofsson, Johan; Schreiber, Matthias R.; Bayo, Amelia; Cáceres, Claudio; Montesinos, Matías
We present polarized light observations of the transitional disc around Sz 91 acquired with VLT/NaCo at H (1.7μm) and Ks (2.2μm) bands. We resolve the disc and detect polarized emission up to ∼0.5 arcsec (∼80 au) along with a central cavity at both bands. We computed a radiative transfermodel that accounts for themain characteristics of the polarized observations. We found that the emission is best explained by small, porous grains distributed in a disc with a ∼45 au cavity. Previous ALMA observations have revealed a large sub-mm cavity (∼83 au) and extended gas emission from the innermost (<16 au) regions up to almost 400 au from the star. Dynamical clearing by multiple low-mass planets arises as the most probable mechanism for the origin of Sz 91’s peculiar structure. Using new L -band ADI observations, we can rule out companions more massive than Mp ≥ 8 MJup beyond 45 au assuming hot-start models. The disc is clearly asymmetric in polarized light along the minor axis, with the north side brighter than the south side. Differences in position angle between the disc observed at sub-mm wavelengths with ALMA and our NaCo observations were found. This suggests that the disc around Sz 91 could be highly structured. Higher signal-to-noise near-IR and sub-mm observations are needed to confirm the existence of such structures and to improve the current understanding of the origin of transitional discs.
Efecto del conflicto decisional sobre el control del asma en escolares de 10 a 14 años
(Sociedad Chilena de Enfermedades Respiratorias, 2020) Ciudad A., Daniel; Bravo S., Gabriela; Contreras A., Linrayén; Huenul V., Yocelin
Introducción: La cantidad de pacientes asmáticos que asisten al sistema público de salud es cada vez mayor, no obstante, la tasa de adherencia al tratamiento es muy baja, siendo los adolescentes quienes presentan mayor porcentaje de abandono al tratamiento, inasistencia a sus controles y gran conflicto decisional (CD). El objetivo de este estudio fue evaluar el efecto de la aplicación de consejerías sobre el CD en relación al tratamiento del asma y el nivel de control de su enfermedad. Materiales y Métodos: Estudio pre-experimental que reclutó a 32 niños asmáticos entre 10 a 14 años de edad del policlínico respiratorio infantil del hospital Carlos Van Buren de Valparaíso. Solo 15 niños estuvieron dispuestos a participar en el estudio quienes completaron la totalidad de las sesiones de consejería. Para determinar el grado de CD de su patología, se aplicó la Escala de Conflicto Decisional de Ottawa; y para el nivel del control del asma, se usó la Escala Global Initiative for Asthma (GINA). Resultados: La edad media del grupo de niños fue de 12,06 ± 1,16 años. Finalizada la intervención, el nivel de control de asma se mantuvo y la media del CD disminuyó de 34,05 ± 4,59 a 18,02 ± 3,01 puntos (p < 0,05; t de Student para muestras pareadas). Un 73,3% de los pacientes disminuyó su nivel de conflicto decisional. Conclusión: Las consejerías de apoyo decisional demostraron tener efectos positivos en la población estudiada.
Experimental Framework to Simulate Rescue Operations after a Natural Disaster
(Universidad Nacional de La Plata: Facultad de Informática, 2020) Veas-Castillo, Luis; Ovando-Leon, Gabriel; Astudillo, Gabriel; Gil-Costa, Veronica; Marín, Mauricio
Computational simulation is a powerful tool for performance evaluation of computational systems. It is useful to make capacity planning of data center clusters, to obtain profiling reports of software applications and to detect bottlenecks. It has been used in different research areas like large scale Web search engines, natural disaster evacuations, computational biology, human behavior and tendency, among many others. However, properly tuning the parameters of the simulators, defining the scenarios to be simulated and collecting the data traces is not an easy task. It is an incremental process which requires constantly comparing the estimated metrics and the flow of simulated actions against real data. In this work, we present an experimental framework designed for the development of large scale simulations of two applications used upon the occurrence of a natural disaster strikes. The first one is a social application aimed to register volunteers and manage emergency campaigns and tasks. The second one is a benchmark application a data repository named MongoDB. The applications are deployed in a distributed platform which combines different technologies like a Proxy, a Containers Orchestrator, Containers and a NoSQL Database. We simulate both applications and the architecture platform. We validate our simulators using real traces collected during simulacrums of emergency situations.
Height in twentieth‐century Chilean men: growth with divergence
(Springer-Verlag, 2020) Llorca‐Jaña, Manuel; Navarrete‐Montalvo, Juan; Araya‐Valenzuela, Roberto; Droller, Federico; Allende, Martina; Rivas, Javier
This article provides the frst series of Chilean adult male height for the whole of the twentieth century. The height of adult males increased by about 5.5 cm during the twentieth century, primarily during the second half of this period. This is the greatest improvement in biological welfare in Chilean history; Chilean males have never been as tall as they are today. Using a sample of around 36,371 individuals, we document the evolution of the average height of Chilean soldiers (male) born from the 1900s to the 1990s. This sample can be safely taken as a good proxy of the average height of Chilean male population for the period under study. We provide an explanation of both the main determinants of physical stature and the rapid increase in height in Chile over this period.
The Big Bang Theory o las reflexiones finales que inician el cambio. Revisando las creencias de los docentes para construir una didáctica para la Educación Física Escolar
(Federación Española de Asociaciones de Docentes de Educación Física (FEADEF), 2020) Trigueros Cervantes, Carmen; Rivera García, Enrique; Moreno Doña, Alberto
Esta investigación tiene el objetivo principal analizar las teorías implícitas de los docentes sobre las funciones y consideración social de la Educación Física Escolar (EFE) en la sociedad actual. Dicho estudio se lleva a cabo desde un paradigma interpretativo, recabando la información a través de un grupo de discusión de ocho docentes de Primaria y Secundaria. Para su análisis se ha profundizado en cuatro categorías centrales: presencia de la EFE en el contexto escolar, percepción social del área, funciones que le asignan socialmente y preocupaciones percibidas por los docentes. Las conclusiones obtenidas identifican el valor social que le otorgan, llegando en ocasiones a un exceso de reconocimiento frente a otras materias del currículum. Tras esta valoración aparecen las competencias y objetivos a trabajar desde la EFE para seguir reclamando mayor reconocimiento social. Por último, se revisan las funciones que se le asigna a la EFE, destacando las referidas a la socialización y expresión de emociones, junto con el fomento de la salud y la atención a la diversidad.
Formación inicial de maestros de educación física: conectando un quehacer pedagógico decolonial con la intervención social, política e insurgente del espacio público
(Federación Española de Asociaciones de Docentes de Educación Física (FEADEF), 2020) Moreno Doña, Alberto; Toro Arévalo, Sergio; Gómez Gonzalvo, Fernando
No existe un único enfoque adecuado para establecer los criterios que han de definir la formación inicial de maestros(as). Ello debido a que cada orientación responde a unos intereses que se legitiman y a otros que se niegan. Existe una tendencia, cada vez mayor, a construir y normalizar un conocimiento técnico entre el alumnado universitario de los grados de magisterio. Siempre desde una lógica epistemológica eurocéntrica que se fundamenta en algunas evidencias científico-pedagógicas. Muchas regiones del planeta están adoptando este tipo de perspectivas como propias y, al mismo tiempo, negando otras formas de habitar la escuela y otros conocimientos que no poseen una base científica europea. De esta forma, se deslegitiman propuestas pedagógicas realizadas desde los márgenes, puesto que la lógica colonial europea deshumaniza a las personas que habitan estos espacios debido a las relaciones de poder existentes en el eje Norte-Sur. Por esto se reflexiona y analiza una lógica decolonial de la pedagogía de educación física que centre sus acciones en el buen vivir, en la exploración de la vida en sintonía con lo natural, en la reciprocidad con los otros seres vivos y en la transformación de los límites espaciotemporales de la formación de maestros(as) a través de la acción colectiva y desde un posicionamiento ético y político basado en la autogestión. Es por esto por lo que proponemos una práctica educativa transgresora de las normas educativas imperantes y que transita hacia un devenir educativo basado en los aprendizajes encarnados, situados y contextualizados para la formación de los futuros maestros(as) de educación física.
The Gaia–ESO Survey: Carbon Abundance in the Galactic Thin and Thick Disks
(The American Astronomical Society, 2020) Bayo, Amelia
This paper focuses on carbon, which is one of the most abundant elements in the universe and is of high importance in the field of nucleosynthesis and galactic and stellar evolution. The origin of carbon and the relative importance of massive and low- to intermediate-mass stars in producing it is still a matter of debate. We aim at better understanding the origin of carbon by studying the trends of [C/H], [C/Fe], and [C/Mg] versus [Fe/H] and [Mg/H] for 2133 FGK dwarf stars from the fifth Gaia–ESO Survey internal data release (GES iDR5). The availability of accurate parallaxes and proper motions from Gaia DR2 and radial velocities from GES iDR5 allows us to compute Galactic velocities, orbits, absolute magnitudes, and, for 1751 stars, Bayesian-derived ages. Three different selection methodologies have been adopted to discriminate between thin- and thick-disk stars. In all the cases, the two stellar groups show different [C/H], [C/Fe], and [C/Mg] and span different age intervals, with the thick-disk stars being, on average, older than the thin-disk ones. The behaviors of [C/H], [C/Fe], and [C/Mg] versus [Fe/H], [Mg/H], and age all suggest that C is primarily produced in massive stars. The increase of [C/Mg] for young thin-disk stars indicates a contribution from low-mass stars or the increased C production from massive stars at high metallicities due to the enhanced mass loss. The analysis of the orbital parameters Rmed and ∣Zmax∣ supports an “inside–out” and “upside–down” formation scenario for the disks of the Milky Way.
Bodily distribution of projectile injuries in Chilean protests
(Elsevier, 2020) Cox, Pablo; Riveros, Rodrigo; Leiva, Camila; Carvajal, Yuri; Fuentes, Pablo; Recasens, Jaime; Covarrubias, Alvaro; Torres, Francisco; Ramírez, Daniel; Verdugo, Marcelo; Muñoz, Pablo
The ALPINE-ALMA [CII] survey: Small Lya-[CII] velocity offsets in main-sequence galaxies at 4.4 < z < 6
(European Southern Observatory, 2020) Ibar, Eduardo; Mendez Hernandez, Hugo
Context. The Lyman- line in the ultraviolet (UV) and the [CII] line in the far-infrared (FIR) are widely used tools to identify galaxies in the early Universe and to obtain insights into interstellar medium (ISM) properties in high-redshift galaxies. By combining data obtained with ALMA in band 7 at 320 GHz as part of the ALMA Large Program to INvestigate [CII] at Early Times (ALPINE) with spectroscopic data from DEIMOS at the Keck Observatory, VIMOS and FORS2 at the Very Large Telescope, we assembled a unique sample of 53 main-sequence star-forming galaxies at 4:4 < z < 6 in which we detect both the Lyman- line in the UV and the [CII] line in the FIR. Aims. The goal of this paper is to constrain the properties of the Ly emission in these galaxies in relation to other properties of the ISM. Methods. We used [CII], observed with ALMA, as a tracer of the systemic velocity of the galaxies, and we exploited the available optical spectroscopy to obtain the Ly -[CII] and ISM-[CII] velocity offsets. Results. We find that 90% of the selected objects have Ly -[CII] velocity offsets in the range 0 < vLy ��[CII] < 400 km s��1, in line with the few measurements available so far in the early Universe, and significantly smaller than those observed at lower redshifts. At the same time, we observe ISM-[CII] offsets in the range ��500 < vISM��[CII] < 0 km s��1, in line with values at all redshifts, which we interpret as evidence for outflows in these galaxies. We find significant anticorrelations between vLy ��[CII] and the Ly rest-frame equivalent width EW0(Ly ) (or equivalently, the Ly escape fraction fesc(Ly )): galaxies that show smaller vLy ��[CII] have larger EW0(Ly ) and fesc(Ly ). Conclusions. We interpret these results in the framework of available models for the radiative transfer of Ly photons. According to the models, the escape of Ly photons would be favored in galaxies with high outflow velocities, producing large EW0(Ly ) and small vLy ��[CII], in agreement with our observations. The uniform shell model would also predict that the Ly escape in galaxies with slow outflows (0 < vout < 300 km s��1) is mainly determined by the neutral hydrogen column density (NHI) along the line of sight, while the alternative model by Steidel et al. (2010) would more highly favor a combination of NHI at the systemic velocity and covering fraction as driver of the Ly escape. We suggest that the observed increase in Ly escape that is observed in the literature between z 2 and z 6 is not due to a higher incidence of fast outflows at high redshift, but rather to a decrease in average NHI along the line of sight, or alternatively, a decrease in HI covering fraction
Thermodynamic Formalism in Neuronal Dynamics and Spike Train Statistics
(MDPI, 2020) Cofré, Rodrigo
The Thermodynamic Formalism provides a rigorous mathematical framework for studying quantitative and qualitative aspects of dynamical systems. At its core, there is a variational principle that corresponds, in its simplest form, to the Maximum Entropy principle. It is used as a statistical inference procedure to represent, by specific probability measures (Gibbs measures), the collective behaviour of complex systems. This framework has found applications in different domains of science. In particular, it has been fruitful and influential in neurosciences. In this article, we review how the Thermodynamic Formalism can be exploited in the field of theoretical neuroscience, as a conceptual and operational tool, in order to link the dynamics of interacting neurons and the statistics of action potentials from either experimental data or mathematical models. We comment on perspectives and open problems in theoretical neuroscience that could be addressed within this formalism

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