Artículos investigadores UV

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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.
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.
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.
¿Qué tecnología escojo para mi clase? Percepción de estudiantes de medicina sobre clickers y Kahoot
(Fundación Educación Médica, 2020) Guerra Zuñiga, Maria; Cuevas Lang, Katherine; Segovia Chamorro, Jaime
Introducción: Las nuevas generaciones de estudiantes y las distintas problemáticas de las asignaturas instan a modificar las actividades formativas hacia nuevas formas utilizando tecnologías de la información y la comunicación. Objetivo: Identificar la opinión de los alumnos de primer y segundo año de la carrera de medicina, Universidad de Valparaíso, respecto del uso de un sistema inalámbrico de respuesta (clicker) y Kahoot en el aula. Sujetos y métodos: Estudio cualitativo, fenomenológico. Para la producción de información se realizaron 2 grupos focales con un total de 18 participantes, los cuales se transcribieron según el principio de verbatim. El análisis utilizado fue de contenido. Se efectuó triangulación de la información con técnica de investigadores. Resultados: El uso de clickersy Kahoot se ha valorado positivamente. Se produjo información acerca de las ventajas e inconvenientes de cada una de las tecnologías. Ambas logran focalizar la atención de los estudiantes y aumentan su sensación de disfrute, aprendizaje y calidad de vida al ser estrategias de gamificación. Conclusión: Ambas estrategias tienen la potencialidad de modificar favorablemente los ambientes del aula, con ventajas y limitaciones que deben ser conocidas por los docentes. Es relevante insertarlas dentro de estrategias educativas coherentes para potenciar los procesos de enseñanza-aprendizaje.
Cataclysmic variable evolution and the white dwarf mass problem: A Review
(Elsevier, 2020) Zorotovic, Mónica; Schreiber, Matthias R.
Although the theory of cataclysmic variable (CV) evolution is able to explain several observational aspects, strong discrepancies have existed for decades between observations and theoretical predictions of the orbital period distribution, the location of the minimum period, and the space density of CVs. Moreover, it has been shown in the last decade that the average white dwarf (WD) mass observed in CVs is significantly higher than the average mass in single WDs or in detached progenitors of CVs, and that there is an absence of helium-core WDs in CVs which is not observed in their immediate detached progenitors. This highly motivated us to revise the theory of CV formation and evolution. A new empirical model for angular momentum loss in CVs was developed in order to explain the high average WD mass observed and the absence of systems with helium-core WDs. This model seems to help, at the same time, with all of the above mentioned disagreements between theory and observations. Moreover, it also provides us with a very likely explanation for the existence of low-mass WDs without a companion. Here we will review the standard model for CV evolution and the disagreements that have existed for decades between simulations and observations with their possible solutions and/or improvements. We will also summarize the recently confirmed disagreement related to the average WD mass and the fraction of helium-core WDs among CVs, as well as the development of an empirical model that allows us to solve all the disagreements, discussing the physics that could be involved.
Polis en conflicto: memoria urbana del Golpe de Estado de septiembre de 1973 en Valparaíso, Chile
(Centro de Investigaciones Geográficas, 2020) Castañeda Meneses, Patricia; Cazorla Becerra, Ketty; Cuevas Lang, Katherine
En Chile, el 11 de septiembre de 1973 se produce un Golpe de Estado que inicia una dictadura cívico militar que se extendió hasta marzo de 1990. El presente trabajo tiene por objetivo rescatar la memoria urbana de la población mayor de Valparaíso respecto del desarrollo del Golpe de Estado en la ciudad. Se realizó un trabajo de campo aplicando 32 entrevistas cualitativas de enfoque biográfico. Los resultados indican que la memoria de la ciudad reconoce en el Golpe de Estado un hito que fracturó la polis a través de la ruptura del espacio político ciudadano debido a la intervención militar. Como consecuencia, las relaciones entre el Estado y la ciudadanía quedaron retenidas dentro de un marco dictatorial de 17 años, aportando un complejo legado de confrontación urbana definida desde el conflicto y la hostilidad.
Editorial: Celebrating 40 Years of the Chilean Society of Pharmacology
(Frontiers, 2020) Yévenes, Gonzalo E.; Bravo, Javier A.; Díaz-Araya, Guillermo; Sotomayor-Zárate, Ramón; Fiedler, Jenny L.; Reyes-Parada, Miguel; Fuentealba, Jorge
Editorial on the Research Topic. Celebrating 40 Years of the Chilean Society of Pharmacology
The White Dwarf Binary Pathways Survey −III. Contamination from hierarchical triples containing a white dwarf
(Royal Astronomical Society, 2020) Lagos, Felipe; Schreiber, Matthias R.; Hernández, M-H; Tappert, Claus; Zorotovic, Mónica; Cáceres, C.
The White Dwarf Binary Pathways Survey aims at increasing the number of known detached A, F, G, and K main-sequence stars in close orbits with white dwarf companions (WD+AFGK binaries) to refine our understanding about compact binary evolution and the nature of Supernova Ia progenitors. These close WD+AFGK binary stars are expected to form through common envelope evolution, in which tidal forces tend to circularize the orbit. However, some of the identified WD+AFGK binary candidates show eccentric orbits, indicating that these systems are either formed through a different mechanism or perhaps they are not close WD+AFGK binaries. We observed one of these eccentric WD+AFGK binaries with SPHERE and find that the system TYC 7218-934-1 is in fact a triple system where the WD is a distant companion. The inner binary likely consists of the G-type star plus an unseen low-mass companion in an eccentric orbit. Based on this finding, we estimate the fraction of triple systems that could contaminate the WD+AFGK sample. We find that less than 15 per cent of our targets with orbital periods shorter than 100 d might be hierarchical triples.
Los trastornos mentales de nietzsche: locura, estar enfermo, “llega a ser el que eres”.
(Scielo, 2020) Figueroa, Gustavo
Desde su niñez Nietzsche padeció de variadas enfermedades y desde esa época intentó aprehender el significado de “¿Qué sentido tiene el enfermar”? 1] Durante sus últimos años desarrolló una demencia progresiva diagnosticada como parálisis progresiva atípica, pero los avances en la genética molecular han puesto en duda el concepto original. 2] Su historia médica consistió en numerosos problemas graves que incluyó cefaleas persistentes, alteraciones gástricas con fuerte impacto en su vida cotidiana, pérdida progresiva de la visión, reumatismo, alteraciones afectivas intermitentes. 3] Ser enfermo para Nietzsche es un proyecto de mundo, el modo y manera en el cual se tornan accesibles los entes para él, que resultó en un estrechamiento, constricción, expansión o modo creativo de ser-en-el-mundo.
Challenging matter creation models in the phantom divide
(American Physical Society, 2020) Cardenas, Victor H.; Cruz, Miguel; Lepe, Samuel; Nojiri, Shin’ichi; Odintsov, Sergei D.
We perform a study both statistical and theoretical for cosmological models of matter creation and their ability to describe effective phantom models of dark energy. Such models are beyond the ΛCDM model since the resulting cosmic expansion is not adiabatic. In fact, we show that this approach exhibits transient phantom/quintessence scenarios at present time and tends to the standard cosmological model at some stage of the cosmic evolution. We discuss some generalities of the thermodynamics properties for this type of cosmological model; we emphasize on the behavior of the temperature associated to dark matter, which keeps positive along cosmic evolution together with the entropy. The enrichment of this type of model by means of the incorporation of cosmological constant and dissipative effects in the fluid description to explore their cosmological consequences in the expansion of the Universe is considered. Finally, a generalization for the matter production rate as an inhomogeneous expression of the Hubble parameter and its derivatives is discussed; as in all the cases examined, such election leads to an effective phantom/quintessence behavior
Phytostimulant properties of highly stable silver nanoparticles obtained with saponin extract from Chenopodium quinoa
(Society of Chemical Industry, 2020) Segura, Rodrigo; Vásquez, Gustavo; Colson, Emmanuel; Gerbaux, Pascal; Frischmon, Caroline; Nesic, Aleksandra; García, Danni E; Cabrera-Barjas, Gustavo
BACKGROUND: Quinoa (Chenopodium quinoa Willd) is an Andean original pseudocereal with high nutritional value. During quinoa processing, large amounts of saponin-rich husks byproducts are obtained. Quinoa saponins, which are biologically active, could be used for various agriculture purposes. Silver nanoparticles have increasingly attracted attention for the management of crop diseases in agriculture. In this work, silver nanoparticles are synthesized by a sustainable and green method, using quinoa husk saponin extract (QE) to evaluate their potential for application in agriculture as biostimulants. RESULTS: Quinoa extract was obtained and characterized by liquid chromatography with tandem mass spectrometry (LC–MS/ MS). Sixteen saponin congeners were successfully identified and quantified. The QE obtained was used as a reducing agent for silver ions to synthesize silver nanoparticles (QEAgNPs) under mild conditions. The morphology, particle size, and stability of Ag nanoparticles were investigated by transmission electron microscopy (TEM), ultraviolet–visible spectroscopy (UV-visible), energy-dispersive X-ray (EDS), zeta potential, and Fourier transform infrared spectroscopy with attenuated total reflection (FTIR-ATR). Ultraviolet–visible spectroscopy measurements confirmed the formation of silver nanoparticles in the presence of QE, with estimated particle sizes in a range between 5 and 50 nm. According to the zeta potential values, highly stable nanoparticles were formed. The QE and QEAgNPs (200–1000 ∼g/mL) were also tested in radish seed bioassay to evaluate their phytotoxicity. The seed germination assays revealed that QEAgNPs possessed a phytostimulant effect on radish seeds in a dosedependent manner, and no phytotoxicity was observed for both QE and QEAgNPs. CONCLUSION: Silver nanoparticles obtained by a so-called ‘green’ method could be considered as good candidates for application in the agricultural sector for seed treatment, or as foliar sprays and plant-growth-promoters.
A Story of Four Eggs in Goto Island, Japan
(Coastal Education and Research Foundation, 2020) Winckler Grez, Patricio
The challenge of measuring the phase function of debris disks: Application to HR4796
(European Southern Observatory, 2020) Olofsson, Johan; Bayo, Amelia
Context. Debris discs are valuable systems to study dust properties. Because they are optically thin at all wavelengths, we have direct access to the absorption and scattering properties of the dust grains. One very promising technique to study them is to measure their phase function, that is, the scattering efficiency as a function of the scattering angle. Discs that are highly inclined are promising targets as a wider range of scattering angles can be probed. Aims. The phase function (polarised or total intensity) is usually either inferred by comparing the observations to synthetic disc models, assuming a parametrised phase function or estimating it from the surface brightness of the disc. Here, we argue that the latter approach can be biased due to projection effects leading to an increase in column density along the major axis of a non-flat disc. Methods. We present a novel approach to account for those column density effects. The method remains model dependent, as a disc model is still required to estimate the density variations as a function of the scattering angle. This method allows us, however, to estimate the shape of the phase function without having to invoke any parametrised form. Results. We apply our method to SPHERE/ZIMPOL observations of HR 4796 A and highlight the differences with previous measurements only using the surface brightness; the main differences being at scattering angles smaller than ~100°. Our modelling results suggest that the disc is not vertically flat at optical wavelengths; this result is supported by comparing the width along the major and minor axis of synthetic images. We discuss some of the caveats of the approach, mostly that our method remains blind to real local increases in the dust density and that it cannot be readily applied to angular differential imaging observations yet. Conclusions. We show that the vertical thickness of inclined (≥60°) debris discs can affect the determination of their phase functions. Similarly to previous studies on HR 4796 A, we still cannot reconcile the full picture using a given scattering theory to explain the shape of the phase function, the blow-out size due to radiation pressure, and the shape of the spectral energy distribution, which is a long-lasting problem for debris discs. Nonetheless, we argue that similar effects, such as the ones highlighted in this study, can also bias the determination of the phase function in total intensity.
Protective effect of the hydroalcoholic extract from Lampaya medicinalis Phil. (Verbenaceae) on palmitic acid- impaired insulin signaling in 3T3-L1 adipocytes
(Elsevier, 2020) Ormazabal, Paulina; Herrera, Karin; Cifuentes, Mariana; Paredes, Adrián; Morales, Glauco; Cruz, Gonzalo
Background: Obesity is strongly associated with insulin resistance (IR). IR at the molecular level may bedefined as a diminished activation of insulin signaling-related molecules (IRS-1/Akt/AS160) as well asreduced glucose uptake. Subject with obesity have elevated plasma levels of saturated fatty acids, suchas palmitic acid (PA), which triggers insulin signaling disruption in vivo and in vitro. Infusions of Lampayamedicinalis Phil. (Verbenaceae) are used in folk medicine of Northern Chile to counteract inflammatorydiseases. Hydroethanolic extracts of lampaya (HEL) contain considerable amounts of flavonoids that mayexplain the biological activity of the plant. The aim of this study was to assess whether HEL exposureprotects against PA-disrupted insulin signaling and glucose uptake in adipocytes.Methods: Cytotoxicity of a range of HEL concentrations (0.01–10 g/mL) was evaluated in 3T3-L1adipocytes. Cells were exposed or not to 0.1 g/mL of HEL before adding 0.65 mM PA or vehicle andincubated with 100 nM insulin (or vehicle) for 15 min. Phosphorylation of Tyr-IRS-1, Ser-Akt, Thr-AS160was evaluated by Western blot. Glucose uptake was assessed using the 2-NBDG analogue.Results: HEL was not cytotoxic at any concentration assessed. PA-induced reduction in insulin-stimulatedphosphorylation of IRS-1, Akt and AS160 and glucose uptake were abolished by co-treatment with HEL.Conclusion: These findings give new insights about the effect of HEL ameliorating PA- impaired IRS-1/Akt/AS160 pathway and glucose uptake in adipocytes. More studies should focus on lampaya, sincemight represent a preventive approach in individuals whose circulating PA levels contribute to IR.
Gliotransmission: A Novel Target for the Development of Antiseizure Drugs
(Sage, 2020) Riquelme, Julio; Wellmann, Mario; Sotomayor-Zárate, Ramón; Bonansco, Christian
For more than a century, epilepsy has remained an incapacitating neurological disorder with a high incidence worldwide. Mesial temporal lobe epilepsy (TLE) is a common type of epilepsy without an effective pharmacological treatment. An increase in excitability and hypersynchrony of electrical neuronal activity during development are typically associated with an excitatory/inhibitory imbalance in the neuronal network. Astrocytes release gliotransmitters, which can regulate neuronal excitability and synaptic transmission; therefore, the classical neurocentric vision of the cellular basis of epileptogenesis has begun to change. Growing evidence suggests that the key contribution of astrocyte-toneuron signaling in the mechanisms underlies the initiation, propagation, and recurrence of seizure activity. The aim of this review was to summarize current evidence obtained from experimental models that suggest how alterations in astroglial modulation of synaptic transmission and neuronal activity contribute to the development of this brain disease. In this article, we will summarize the main pharmacological, Ca2+-imaging, and electrophysiological findings in the gliotransmitter-mediated modulation of neuronal activity and their possible regulation as a novel cellular target for the development of pharmacological strategies for treating refractory epilepsies.
The ALPINE-ALMA [CII] survey: Little to no evolution in the [CII]–SFR relation over the last 13 Gyr
(European Southern Observatory, 2020) Ibar, Eduardo; Mendez Hernandez, Hugo
The [C ii] 158 m line is one of the strongest IR emission lines, which has been shown to trace the star formation rate (SFR) of galaxies in the nearby Universe, and up to z 2. Whether this is also the case at higher redshift and in the early Universe remains debated. The ALPINE survey, which targeted 118 star-forming galaxies at 4:4 < z < 5:9, provides a new opportunity to examine this question with the first statistical dataset. Using the ALPINE data and earlier measurements from the literature, we examine the relation between the [C ii] luminosity and the SFR over the entire redshift range from z 4 �� 8. ALPINE galaxies, which are both detected in [C ii] and in dust continuum, show good agreement with the local L([CII])–SFR relation. Galaxies undetected in the continuum by ALMA are found to be over-luminous in [C ii]when the UV SFR is used. After accounting for dust-obscured star formation, by an amount of SFR(IR) SFR(UV) on average, which results from two di erent stacking methods and SED fitting, the ALPINE galaxies show an L([CII])–SFR relation comparable to the local one. When [C ii] non-detections are taken into account, the slope may be marginally steeper at high-z, although this is still somewhat uncertain. When compared homogeneously, the z > 6 [C ii] measurements (detections and upper limits) do not behave very di erently to the z 4 �� 6 data.We find a weak dependence of L([CII])/SFR on the Ly equivalent width. Finally, we find that the ratio L([CII])/LIR (1 �� 3) 10��3 for the ALPINE sources, comparable to that of ‘normal’ galaxies at lower redshift. Our analysis, which includes the largest sample ( 150 galaxies) of [C ii] measurements at z > 4 available so far, suggests no or little evolution of the [C ii]–SFR relation over the last 13 Gyr of cosmic time.
The ALPINE-ALMA [CII] survey: Dust attenuation properties and obscured star formation at z ~ 4:4 - 5:8
(European Southern Observatory, 2020) Ibar, Eduardo
We present dust attenuation properties of spectroscopically confirmed star forming galaxies on the main sequence at a redshift of ∼4.4 − 5.8. Our analyses are based on the far infrared continuum observations of 118 galaxies at rest-frame 158 μm obtained with the Atacama Large Millimeter Array (ALMA) Large Program to INvestigate [CII] at Early times (ALPINE). We study the connection between the ultraviolet (UV) spectral slope (β), stellar mass (M⋆), and infrared excess (IRX = LIR/LUV). Twenty-three galaxies are individually detected in the continuum at > 3.5σ significance. We perform a stacking analysis using both detections and nondetections to study the average dust attenuation properties at z ∼ 4.4 − 5.8. The individual detections and stacks show that the IRX–β relation at z ∼ 5 is consistent with a steeper dust attenuation curve than typically found at lower redshifts (z < 4). The attenuation curve is similar to or even steeper than that of the extinction curve of the Small Magellanic Cloud. This systematic change of the IRX–β relation as a function of redshift suggests an evolution of dust attenuation properties at z > 4. Similarly, we find that our galaxies have lower IRX values, up to 1 dex on average, at a fixed mass compared to previously studied IRX–M⋆ relations at z ≲ 4, albeit with significant scatter. This implies a lower obscured fraction of star formation than at lower redshifts. Our results suggest that dust properties of UV-selected star forming galaxies at z ≳ 4 are characterised by (i) a steeper attenuation curve than at z ≲ 4, and (ii) a rapidly decreasing dust obscured fraction of star formation as a function of redshift. Nevertheless, even among this UV-selected sample, massive galaxies (log M⋆/M⊙ > 10) at z ∼ 5 − 6 already exhibit an obscured fraction of star formation of ∼45%, indicating a rapid build-up of dust during the epoch of reionization.
Percepción estudiantil del uso del video como herramienta de retroalimentación a distancia: estudio piloto
(Fundación Educación Médica y Viguera Editores, S.L., 2020) Segovia-Chamorro, Jaime; Guerra-Zúñiga, María
Introducción. Se realizó una intervención consistente en la revisión de una actividad formativa a través de video. Sujetos y métodos. Se diseñó un estudio mixto, que buscó analizar la percepción de los estudiantes a través de un instrumento breve donde posteriormente se realizó un análisis mixto. Resultados. Se encontró una percepción favorable de los estudiantes con bastantes potencialidades, aunque los estudiantes siguen valorando las retroalimentaciones presenciales. Conclusión. La retroalimentación por video es una buena alternativa a la modalidad presencial.
The ALPINE-ALMA [C II] Survey: [C II] 158micron Emission Line Luminosity Functions at z∼4−6
(American Astronomical Society, 2020) Ibar, Eduardo
We present the [C II] 158 μm line luminosity functions (LFs) at z ~ 4–6 using the ALMA observations of 118 sources, which are selected to have UV luminosity M1500Å < −20.2 and optical spectroscopic redshifts in COSMOS and ECDF-S. Of the 118 targets, 75 have significant [C II] detections and 43 are upper limits. This is by far the largest sample of [C II] detections, which allows us to set constraints on the volume density of [C II] emitters at z ~ 4–6. But because this is a UV-selected sample, we are missing [C II]-bright but UV-faint sources, making our constraints strict lower limits. Our derived LFs are statistically consistent with the z ~ 0 [C II] LF at 108.25–109.75L⊙. We compare our results with the upper limits of the [C II] LF derived from serendipitous sources in the ALPINE maps. We also infer the [C II] LFs based on published far-IR and CO LFs at z ~ 4–6. Combining our robust lower limits with these additional estimates, we set further constraints on the true number density of [C II] emitters at z ~ 4–6. These additional LF estimates are largely above our LF at L[CII] > 109L⊙, suggesting that UV-faint but [C II]-bright sources likely make significant contributions to the [C II] emitter volume density. When we include all the LF estimates, we find that available model predictions underestimate the number densities of [C II] emitters at z ~ 4–6. Finally, we set a constraint on the molecular gas mass density at z ~ 4–6, with ρmol ~ (2–7) × 107M⊙ Mpc−3. This is broadly consistent with previous studies.

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