23 research outputs found
Formation of Solar system analogues – II: Post-gas-phase growthand water accretion in extended discs via N-body simulations
This work is the second part of a project that attempts to analyse the formation of Solar system analogues (SSAs) from the gaseous to the post-gas phase, in a self-consistently way. In the first paper (PI) we presented our model of planet formation during the gaseous phase which provided us with embryo distributions, planetesimal surface density, eccentricity, and inclination profiles of SSAs, considering different planetesimal sizes and type I migration rates at the time the gas dissipates. In this second work we focus on the late accretion stage of SSAs using the results obtained in PI as initial conditions to carry out N-body simulations. One of our interests is to analyse the formation of rocky planets and their final water contents within the habitable zone. Our results show that the formation of potentially habitable planets (PHPs) seems to be a common process in this kind of scenarios. However, the efficiency in forming PHPs is directly related to the size of the planetesimals. The smaller the planetesimals, the greater the efficiency in forming PHPs. We also analyse the sensitivity of our results to scenarios with type I migration rates and gap-opening giants, finding that both phenomena act in a similar way. These effects seem to favour the formation of PHPs for small planetesimal scenarios and to be detrimental for scenarios formed from big planetesimals. Finally, another interesting result is that the formation of water-rich PHPs seems to be more common than the formation of dry PHPs.Fil: Ronco, María Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina. Pontificia Universidad Católica de Chile; ChileFil: de Elia, Gonzalo Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentin
Production of hot Jupiter candidates from high-eccentricity mechanisms for different initial planetary mass configurations
Hot Jupiters (HJs) are giant planets with orbital periods of the order of a few days with semimajor axis within ∼0.1 au. Several theories have been invoked in order to explain the origin of this type of planets, one of them being the high-eccentricity migration. This migration can occur through different high-eccentricity mechanisms. Our investigation focused on six different kinds of high-eccentricity mechanisms, namely, direct dispersion, coplanar, Kozai-Lidov, secular chaos, E1 and E2 mechanisms. We investigated the efficiency of these mechanisms for the production of HJ candidates in multiplanet systems initially tightly-packed in the semimajor axis, considering a large set of numerical simulations of the exact equations of motion in the context of the N-body problem. In particular, we analyzed the sensitivity of our results to the initial number of planets, the initial semimajor axis of the innermost planetary orbit, the initial configuration of planetary masses, and to the inclusion of general relativity (GR) effects. We found that the E1 mechanism is the most efficient in producing HJ candidates both in simulations with and without the contribution of GR, followed by the Kozai-Lidov and E2 mechanisms. Our results also revealed that, except for the initial equal planetary mass configuration, the E1 mechanism was notably efficient in the other initial planetary mass configurations considered in this work. Finally, we investigated the production of HJ candidates with prograde, retrograde, and alternating orbits. According to our statistical analysis, the Kozai-Lidov mechanism has the highest probability of significantly exciting the orbital inclinations of the HJ candidates.Fil: Garzón, H.. Universidade Federal do Rio de Janeiro; BrasilFil: Rodríguez, Adrián. Universidade Federal do Rio de Janeiro; BrasilFil: de Elia, Gonzalo Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentin
Terrestrial planets in high-mass disks without gas giants
Context. Observational and theoretical studies suggest that planetary systems consisting only of rocky planets are probably the most common in the Universe. Aims. We study the potential habitability of planets formed in high-mass disks without gas giants around solar-type stars. These systems are interesting because they are likely to harbor super-Earths or Neptune-mass planets on wide orbits, which one should be able to detect with the microlensing technique. Methods. First, a semi-analytical model was used to define the mass of the protoplanetary disks that produce Earth-like planets, superEarths, or mini-Neptunes, but not gas giants. Using mean values for the parameters that describe a disk and its evolution, we infer that disks with masses lower than 0.15 M are unable to form gas giants. Then, that semi-analytical model was used to describe the evolution of embryos and planetesimals during the gaseous phase for a given disk. Thus, initial conditions were obtained to perform N-body simulations of planetary accretion. We studied disks of 0.1, 0.125, and 0.15 M. Results. All our simulations form massive planets on wide orbits. For a 0.1 M disk, 2–3 super-Earths of 2.8 to 5.9 M⊕ are formed between 2 and 5 AU. For disks of 0.125 and 0.15 M, our simulations produce a 10–17.1 M⊕ planet between 1.6 and 2.7 AU, and other super-Earths are formed in outer regions. Moreover, six planets survive in the habitable zone (HZ). These planets have masses from 1.9 to 4.7 M⊕ and significant water contents ranging from 560 to 7482 Earth oceans, where one Earth ocean represents the amount of water on Earth’s surface, which equals 2.8 × 10−4 M⊕. Of the six planets formed in the HZ, three are water worlds with 39%–44% water by mass. These planets start the simulations beyond the snow line, which explains their high water abundances. In general terms, the smaller the mass of the planets observed on wide orbits, the higher the possibility to find water worlds in the HZ. In fact, massive planets can act as a dynamical barrier that prevents the inward diffusion of water-rich embryos located beyond the snow line. Conclusions. Systems without gas giants that harbor super-Earths or Neptune-mass planets on wide orbits around solar-type stars are of astrobiological interest. These systems are likely to harbor super-Earths in the HZ with significant water contents, which missions such as Kepler and Darwin should be able to find.Fil: de Elia, Gonzalo Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica la Plata; ArgentinaFil: Guilera, Octavio Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica la Plata; ArgentinaFil: Brunini, Adrian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica la Plata; Argentin
Water worlds in N-body simulations with fragmentation in systems without gaseous giants
We analyze the formation and evolution of terrestrial-like planets around solar-type stars in the absence of gaseous giants. In particular, we focus on the physical and dynamical properties of those that survive in the system´s Habitable Zone (HZ). This investigation is based on a comparative study between N-body simulations that include fragmentation and others that consider all collisions as perfect mergers.We use an N-body code, presented in a previous paper, that allows planetary fragmentation. We carry out three sets of 24 simulations for 400 Myr. Two sets are developed adopting a model that includes hit-and-run collisions and planetary fragmentation, each one with different values of the individual minimum mass allowed for the fragments. For the third set, we considered that all collisions lead to perfect mergers.The planetary systems produced in N-body simulations with and without fragmentation are broadly similar, with some differences. In simulations with fragmentation, the formed planets have lower masses since part it is distributed amongst collisional fragments. Additionally, those planets presented lower eccentricities, presumably due to dynamical friction with the generated fragments. Lastly, perfect mergers and hit-and-run collisions are the most common outcome.Regardless of the collisional treatment adopted, most of the planets that survive in the HZ start the simulation beyond the snow line, having very high final water contents. Such planets are called water worlds. The fragments´ contribution to their final mass and water content is negligible. Finally, the individual minimum mass for fragments may play an important role in the planets´ collisional history.Collisional models that incorporate fragmentation and hit-and-run collisions lead to a more detailed description of the physical properties of the terrestrial-like planets formed. We conclude that planetary fragmentation is not a barrier to the formation of water worlds in the HZ. The results shown in this work suggest that further refinement is necessary to have a more realistic model of planetary formation.Fil: Dugaro, Agustin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; ArgentinaFil: de Elia, Gonzalo Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; ArgentinaFil: Darriba, Luciano Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentin
Tidal and general relativistic effects in rocky planet formation at the sub-stellar mass limit using N-body simulations
Context. Recent observational results show that very low mass stars and brown dwarfs are able to host close-in rocky planets. Low-mass stars are the most abundant stars in the Galaxy and the formation efficiency of their planetary systems is relevant in the computation of a global probability of finding Earth-like planets inside habitable zones. Tidal forces and relativistic effects are relevant inthe latest dynamical evolution of planets around low-mass stars and their effect on the planetary formation efficiency still needs to beaddressed.Aims. Our goal is to evaluate the impact of tidal forces and relativistic effects on the formation of rocky planets around a star close tothe sub-stellar mass limit, in terms of the resulting planetary architectures and its distribution according to the corresponding evolving habitable zone.Methods. We performed a set of N-body simulations spanning the first 100 Myr of the evolution of two systems composed respectively by 224 embryos with a total mass 0.25M_earth and 74 embryos with a total mass 3 M_earth around a central object of 0.08 M_sun . For both scenarios, we compared the planetary architectures that result from simulations that are purely gravitational with those fromsimulations that include the early contraction and spin up of the central object, the distortions and dissipation tidal terms and generalrelativistic effects.Results. We found that the inclusion of these effects allow the formation and survival of a close-in (r < 0.07 au) population of rockyplanets with masses in the range 0.001 < m/M_earth < 0.02 in all the simulations of the less massive scenario, and a close-in populationwith masses m < 0.35 M_earth in just few of the simulations of the more massive scenario. The surviving close-in bodies suffered highnumber of collisions along the integration time of the simulations which play an important role in their final masses. However, all ofthem conserved their initial amount of water in mass along the integration time.Conclusions. The incorporation of tidal and general relativistic effects allow the formation of an in-situ close-in population located inthe habitable zone of the system. Thus, both effects are relevant during the formation of rocky planet and their early evolution aroundstars close to the sub-stellar mass limit, in particular when low-mass planetary embryos are involved.Fil: Sánchez, María Belén. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; ArgentinaFil: de Elia, Gonzalo Carlos. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; ArgentinaFil: Downes, J. J.. Universidad de la Republica. Centro Universitario Regional del Este.; Urugua
Inverse Lidov-Kozai resonance for an outer test particle due to an eccentric perturber
We analyze the behavior of the argument of pericenter ω2 of an outer particle in the elliptical restricted three-body problem, focusing on the ω2 resonance or inverse Lidov-Kozai resonance. First, we calculate the contribution of the terms of quadrupole, octupole, and hexadecapolar order of the secular approximation of the potential to the outer particle´s ω2 precession rate (dω2 /dτ). Then, we derive analytical criteria that determine the vanishing of the ω2 quadrupole precession rate (dω2/dτ)quad for different values of the inner perturber´s eccentricity e1. Finally, we use such analytical considerations and describe the behavior of ω2 of outer particles extracted from N-body simulations developed in a previous work. Our analytical study indicates that the values of the inclination i2 and the ascending node longitude Ω2 associated with the outer particle that vanish (dω2 /dτ)quad strongly depend on the eccentricity e1 of the inner perturber. In fact, if e1 0.40825), (dω2/dτ)quad is only vanished for particles whose Ω2 circulates (librates). For e1 between 0.25 and 0.40825, (dω2 /dτ)quad can be vanished for any particle for a suitable selection of pairs (Ω2 , i2). Our analysis of the N-body simulations shows that the inverse Lidov-Kozai resonance is possible for small, moderate and high values of e1. Moreover, such a resonance produces distinctive features in the evolution of a particle in the (Ω2 , i2 ) plane. In fact, if ω2 librates and Ω2 circulates, the extremes of i2 at Ω2 = 90◦ and270◦ do not reach the same value, while if ω2 and Ω2 librate, the evolutionary trajectory of the particle in the (Ω2, i2) plane evidences an asymmetry respect to i2 = 90◦ . The evolution of ω2 associated with the outer particles of the N-body simulations can be very well explained by the analytical criteria derived in our investigation.Fil: de Elia, Gonzalo Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; ArgentinaFil: Zanardi, Macarena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; ArgentinaFil: Dugaro, Agustin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; ArgentinaFil: Naoz, Smadar. University of California at Los Angeles; Estados Unido
Terrestrial planets and water delivery around low-mass stars
Context. Theoretical and observational studies suggest that protoplanetary disks with a wide range of masses could be found around low-mass stars. Aims: We analyze planetary formation processes in systems without gas giants around M3- and M0-type stars of 0.29 M⊙ and 0.5 M⊙, respectively. In particular, we assume disks with masses of 5% and 10% of the mass of the star. Our study focuses on the formation of terrestrial-like planets and water delivery in the habitable zone (HZ). Methods: First, we use a semi-analytical model to describe the evolution of embryos and planetesimals during the gaseous phase. Then, a N-body code is used to analyze the last giant impact phase after the gas dissipation. Results: For M3-type stars, five planets with different properties are formed in the HZ. These planets have masses of 0.072 M⊕, 0.13 M⊕ (two of them), and 1.03 M⊕, and have water contents of 5.9%, 16.7%, 28.6%, and 60.6% by mass, respectively. Then, the fifth planet formed in the HZ is a dry world with 0.138 M⊕. For M0-type stars, four planets are produced in the HZ with masses of 0.28 M⊕, 0.51 M⊕, 0.72 M⊕, and 1.42 M⊕, and they have water contents of 26.7%, 45.8%, 68%, and 50.5% by mass, respectively. Conclusions: M3- and M0-type stars represent targets of interest for the search of exoplanets in the HZ. In fact, the Mars-mass planets formed around M3-type stars could maintain habitable conditions in their early histories. Thus, the search for candidates around young M3-type stars could lead to the detection of planets analogous to early Mars. Moreover, Earth-mass planets should also be discovered around M3-type stars and, sub- and super-Earths should be detected around M0-type stars. Such planets are very interesting since they could maintain habitable conditions for very long.Fil: Dugaro, Agustin. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica la Plata; ArgentinaFil: de Elia, Gonzalo Carlos. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica la Plata; ArgentinaFil: Brunini, Adrian. Universidad Nacional de la Patagonia Austral. Unidad Academica Caleta Olivia; ArgentinaFil: Guilera, Octavio Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica la Plata; Argentina. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentin
Effects of an eccentric inner Jupiter on the dynamical evolution of icy body reservoirs in a planetary scattering scenario
Aims. We analyze the dynamics of small body reservoirs under the effects of an eccentric inner giant planet resulting from a planetary scattering event around a 0.5 M⊙ star. Methods. First, we used a semi-analytical model to define the properties of the protoplanetary disk that lead to the formation of three Jupiter-mass planets. Then, we carried out N-body simulations assuming that the planets are close to their stability limit together with an outer planetesimal disk. In particular, the present work focused on the analysis of N-body simulations in which a single Jupiter-mass planet survives after the dynamical instability event. Results. Our simulations produce outer small body reservoirs with particles on prograde and retrograde orbits, and other ones whose orbital plane flips from prograde to retrograde and back again along their evolution (“Type-F particles”). We find strong correlations between the inclination i and the ascending node longitude Ω of Type-F particles. First, Ω librates around 90° or/and 270°. This property represents a necessary and sufficient condition for the flipping of an orbit. Moreover, the libration periods of i and Ω are equal and they are out to phase by a quarter period. We also remark that the larger the libration amplitude of i, the larger the libration amplitude of Ω. We analyze the orbital parameters of Type-F particles immediately after the instability event (post IE orbital parameters), when a single Jupiter-mass planet survives in the system. Our results suggest that the orbit of a particle can flip for any value of its post IE eccentricity, although we find only two Type-F particles with post IE inclinations i ≲ 17°. Finally, our study indicates that the minimum value of the inclination of the Type-F particles in a given system decreases with an increase in the eccentricity of the giant planet.Fil: Zanardi, Macarena. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; ArgentinaFil: de Elia, Gonzalo Carlos. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; ArgentinaFil: Di Sisto, Romina Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; ArgentinaFil: Naoz, S.. University of California at Los Angeles; Estados UnidosFil: Li, G.. Harvard-Smithsonian Center for Astrophysics; Estados UnidosFil: Guilera, O. M.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; ArgentinaFil: Brunini, A.. Universidad Nacional de la Patagonia Austral; Argentin
Reseñas
[ES] Seguí de la Riva , Javier. Sobre dibujar y proyectar (por Javier Seguí de la Riva) pp. 4.-- Dibujar, proyectar LVI y LVII Arte y muerte I y II ( por Javier Seguí de la Riva) pp. 6.-- dibujar, proyectar LVIII El imaginario del dibujar (por Javier Seguí de la Riva) pp. 6 y 7.-- Dibujar, proyectar LVI y LVII Diagrama, diagramar I y II ( por Javier Seguí de la Riva) pp. 7.-- DIBUJAR, proyectar LVIII El imaginario del dibujar ( por Javier Seguí de la Riva) pp. 6 y 7.-- DIBUJAR, PROYECTAR LVI y LVII Diagrama, diagramar I y II (por Javier Seguí de la Riva) pp.7.-- DIBUJAR, PROYECTAR LIX, LX y LXI Escritos críticos I, II y III ( por Javier Seguí de la Riva) pp. 7 .-- Rehabilitacion del Antiguo Hospital San Juan de Dios para Biblioteca y Archivo Historico de Orihuela (por Ana Torres Barchino) pp. 8.-- Arnau Amo, Joaquín. Arquitectura. Ritos y ritmos (por María Elia Gutiérrez Mozo) pp. 8 y 9.—Cardone, Vito. Viaggiatori d’architettura in Italia. Da Brunelleschi a Charles Garnier (por Cesare Cundari) pp. 9 y 10.-- Casado de Amezúa Vázquez, Joaquín. Las casas reales de la Alhambra. Geometría y espacio. Una aproximación al proceso de formación del espacio ( por Pilar Chías Navarro)pp. 10.-- Jaén i Urban, Gaspar; Baldomá Soto, Montserrat y Carrasco Martí, Maria Antonia. One century of photography and preservation in catalonia: the service for local architectural heritage ( por Pilar Chías Navarro) pp. 10 y 11.-- Jaén i Urban, Gaspar. El paisaje urbano de Nueva York en la obra escrita de Federico García Lorca (por Concepción López González y Jorge García valldecabres) pp. 11.—Trachana, Angelique. Urbe Ludens ( por Gonzalo García-Rosales) pp. 12.-- Fernández-Palacios, Victoria; Yanguas, Ana; Jiménez Fdez-Palacios, Luz. Manuel Aires Mateus. Cuaderno de La Alhambra ( por José Mª Gentil Baldrich) pp. 12 y 13.-- Agustín, Luis; Miret, Elena; Vallespín, Aurelio. Representación del espacio arquitectónico. 2011.12 (por Jesús Aparicio Guisado) pp. 14.—Herschdorfer, Nathalie y Lada Umstätter, Thames. Le Corbusier and the Power of Photography (por víctor A. Lafuente Sánchez) pp. 14 y 15.-- Roma en el bolsillo. Cuadernos de dibujo y aprendizaje artístico en el siglo XVIII ( por Fernando Linares García) pp. 15 y 16.-- Vicens y Hualde, Ignacio. Dicho y hecho ( por Fernando Linares García) pp 16.-- Le Corbusier. El arte decorativo de hoy ( por Carlos Montes Serrano )pp. 16 y 17.—Jenkins Birkhäuser, Eric J. Drawn to Design: Analyzing Architecture Through Freehand Drawing ( por víctor A. Lafuente Sánchez) pp. 17 y 18.—Sobrino, Miguel. Monasterios. Las biografías desconocidas de los cenobios de España ( por Javier García-Gutiérrez Mosteiro) pp. 18 y 19.-- Jiménez Martín, Alfonso. Anatomía de la Catedral de Sevilla ( por Francisco Pinto Puerto) pp. 19.-- Raposo Grau, Javier Fco; Butragueño Díaz-Guerra, Belen y Paredes Maldonado, Miguel. Dibujar, analizar, proyectar (2010) Título I. Colección dibujo, proyecto y arquitectura ( por Mariasun Salgado de la Rosa) pp. 19 y 20.-- Raposo Grau, Fco Javier; Butragueño Díaz-Guerra, Belen y Paredes Maldonado, Miguel. Dibujar, analizar, proyectar (2011) Título III. Colección dibujo, proyecto y arquitectura ( por Carlos L. Marcos Alba) pp. 20-22.-- García Doménech, Sergio. Reflexiones urbanas sobre el espacio público de Alicante. Una interpretación de la ciudad y sus escenarios ( por Juan Calduch Cervera) pp. 22 y 23.—Cundari, Casere. Il rilievo architettonico. Ragioni. Fondamenti. Applicazioni ( por Antonio Álvaro Tordesillas) pp. 23 y 24.—Autores varios. Perspectiva-Prospettiva. La práctica de la perspectiva ( por José Mª Gentil Baldrich) pp. 24 y 25.-- Soler Sanz, Felipe. Trazados Reguladores en la Arquitectura ( por Jorge García Valldecabres) pp. 25.-- Jiménez Alcañiz, Cesar. Análisis de las metodologías para la recuperación patrimonial de entornos urbanos protegidos. Propuesta metodológica: desde los valores históricos a los nuevos modelos energéticos. Russafa desde el siglo XIX( Por Pablo Navarro Esteve) pp. 26.-- de Coca Leicher, José. El recinto ferial de la Casa de Campo de Madrid (1950-75)( por Esteban Herrero Cantalapiedra) pp. 27.-- La arquitectura religiosa renacentista en tierras del Maestre: la iglesia de Nuestra Señora de la Asunción de Vistabella del Maestrazgo ( por José Teodoro Garfella Rubio) pp. 27 y 28.-- Arquitectura de los balnearios en Galicia. Cuenca del Miño. 1816-1936 ( por José Antonio Franco Taboada)pp. 28 y 29.-- Barros da Rocha e Costa. Historia de la representación gráfica del Castillo de Peñíscola. Del grafito al láser ( por Pablo Navarro Esteve) pp. 29.-- Rivas López, Esteban José. El Carmen de la fundación Rodríguez-Acosta. Una indagación gráfica ( por Joaquín Casado de Amezúa) pp.30.-- Verdejo Gimeno, Pedro. Estaciones intermedias de ferrocarril. La sección “Non nata” Teruel-Alcañiz (por Jorge Girbés Pérez) pp. 30 y 31.-- Sender Contell, Marina. El Monasterio de Santa María de la Murta. Análisis arquitectónico de un Monasterio Jerónimo ( por Pablo Navarro Esteve) pp. 32.-- Iñarra Abad, Susana. El Render de Arquitectura. Análisis de la Respuesta Emocional del Observador ( por Pablo Navarro Esteve) pp. 32 y 33.-- Fernández Morales, Angélica. De concreto a conceptual. Relaciones entre arte y arquitectura en el contexto helvético contemporáneo ( por Luis Agustín) pp. 33.—EXPOSICIÓN: Intervenciones cromáticas en los comercios del centro histórico ( por Jorge Llopis verdú) pp. 34 y 35.Seguí De La Riva, J.; Torres Barchino, A.; Gutiérrez Mozo, ME.; Cundari, C.; Chías Navarro, P.; López González, C.; García Valldecabres, J.... (2014). Reseñas. EGA. Revista de Expresión Gráfica Arquitectónica. 19(24):4-35. https://doi.org/10.4995/ega.2014.3268SWORD435192
Evolving trends in the management of acute appendicitis during COVID-19 waves. The ACIE appy II study
Background: In 2020, ACIE Appy study showed that COVID-19 pandemic heavily affected the management of patients with acute appendicitis (AA) worldwide, with an increased rate of non-operative management (NOM) strategies and a trend toward open surgery due to concern of virus transmission by laparoscopy and controversial recommendations on this issue. The aim of this study was to survey again the same group of surgeons to assess if any difference in management attitudes of AA had occurred in the later stages of the outbreak.
Methods: From August 15 to September 30, 2021, an online questionnaire was sent to all 709 participants of the ACIE Appy study. The questionnaire included questions on personal protective equipment (PPE), local policies and screening for SARS-CoV-2 infection, NOM, surgical approach and disease presentations in 2021. The results were compared with the results from the previous study.
Results: A total of 476 answers were collected (response rate 67.1%). Screening policies were significatively improved with most patients screened regardless of symptoms (89.5% vs. 37.4%) with PCR and antigenic test as the preferred test (74.1% vs. 26.3%). More patients tested positive before surgery and commercial systems were the preferred ones to filter smoke plumes during laparoscopy. Laparoscopic appendicectomy was the first option in the treatment of AA, with a declined use of NOM.
Conclusion: Management of AA has improved in the last waves of pandemic. Increased evidence regarding SARS-COV-2 infection along with a timely healthcare systems response has been translated into tailored attitudes and a better care for patients with AA worldwide