Arquitectura y evolución de sistemas planetarios en resonancias de dos cuerpos

Tesis (Doctor en Astronomía)--Universidad Nacional de Córdoba, Facultad de Matemática, Astronomía, Física y Computación, 2017.En esta tesis se estudia de forma analítica y numérica el movimiento de una partícula de prueba perturbada en un potencial central. Se encuentran dos límites que permiten relacionar diferentes criterios de estabilidad, los cuales separan las regiones de movimiento estable e inestable de dicha partícula. Además, por medio de desarrollos analíticos, simulaciones hidrodinámicas y simulaciones de N-cuerpos, se realiza un estudio de la dinámica resonante de sistemas planetarios inmersos en el disco y en resonancias de movimientos medios. Se encuentra que la relación de períodos de pares de planetas de baja masa resonantes aumenta cuando los planetas migran en discos de gas acampanados. Finalmente, se comparan los resultados con la distribución observada de los sistemas Kepler.In this thesis, the motion of a perturbed test particle in a central potential is studied both analytically and numerically. Two limits are found, enabling us to relate different stability criteria. These limits separate regions of stable and unstable motion. In addition, by mean of analytical developments, hydrodynamical simulations, and N-body simulations, the resonant dynamics of planetary systems embedded in the disk and in mean-motion resonances is studied. It is found that the orbital period ratio of the adjacent pair of low mass resonant planets increases when the planets migrate in flared disks. Finally, the results are compared to the observed distribution of the Kepler systems

Resonance capture and dynamics of three-planet systems

We present a series of dynamical maps for fictitious three-planet systems in initially circular coplanar orbits. These maps have unveiled a rich resonant structure involving two or three planets, as well as indicating possible migration routes from secular to double resonances or pure three-planet commensurabilities. These structures are then compared to the present-day orbital architecture of observed resonant chains. In a second part of the paper, we describe N-body simulations of type-I migration. Depending on the orbital decay time-scale, we show that three-planet systems may be trapped in different combinations of independent commensurabilities: (i) double resonances, (ii) intersection between a two-planet and a first-order three-planet resonances, and (iii) simultaneous libration in two first-order three-planet resonances. These latter outcomes are found for slow migrations, while double resonances are almost always the final outcome in high-density discs. Finally, we discuss an application to the TRAPPIST-1 system. We find that, for low migration rates and planetary masses of the order of the estimated values, most three-planet sub-systems are able to reach the observed double resonances after following evolutionary routes defined by pure three-planet resonances. The final orbital configuration shows resonance offsets comparable with present-day values without the need of tidal dissipation. For the 8/5 resonance proposed to dominate the dynamics of the two inner planets, we find little evidence of its dynamical significance; instead, we propose that this relation between mean motions could be a consequence of the interaction between a pure three-planet resonance and a two-planet commensurability between planets c and d.Instituto de Astrofísica de La Plat

Resonance capture and dynamics of three-planet systems

We present a series of dynamical maps for fictitious three-planet systems in initially circular coplanar orbits. These maps have unveiled a rich resonant structure involving two or three planets, as well as indicating possible migration routes from secular to double resonances or pure three-planet commensurabilities. These structures are then compared to the present-day orbital architecture of observed resonant chains. In a second part of the paper, we describe N-body simulations of type-I migration. Depending on the orbital decay time-scale, we show that three-planet systems may be trapped in different combinations of independent commensurabilities: (i) double resonances, (ii) intersection between a two-planet and a first-order three-planet resonances, and (iii) simultaneous libration in two first-order three-planet resonances. These latter outcomes are found for slow migrations, while double resonances are almost always the final outcome in high-density discs. Finally, we discuss an application to the TRAPPIST-1 system. We find that, for low migration rates and planetary masses of the order of the estimated values, most three-planet sub-systems are able to reach the observed double resonances after following evolutionary routes defined by pure three-planet resonances. The final orbital configuration shows resonance offsets comparable with present-day values without the need of tidal dissipation. For the 8/5 resonance proposed to dominate the dynamics of the two inner planets, we find little evidence of its dynamical significance; instead, we propose that this relation between mean motions could be a consequence of the interaction between a pure three-planet resonance and a two-planet commensurability between planets c and d.Fil: Charalambous, Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Marti, Javier Guillermo. 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: Beauge, Cristian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Ramos, Ximena Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; Argentin

Giga-year evolution of Jupiter Trojans and the asymmetry problem

We present a series of numerical integrations of observed and fictitious Jupiter Trojan asteroids, under the gravitational effects of the four outer planets, for time-spans comparable with the age of the Solar System. From these results we calculate the escape rate from each Lagrange point, and construct dynamical maps of ‘‘permanence’’ time in different regions of the phase space. Fictitious asteroids in L₄ and L₅ show no significant difference, showing almost identical dynamical maps and escape rates. For real Trojans, however, we found that approximately 23% of the members of the leading swarm escaped after 4.5 Gyrs, while this number increased to 28.3% for L₅. This implies that the asymmetry between the two populations increases with time, indicating that it may have been smaller at the time of formation/capture of these asteroids. Nevertheless, the difference in chaotic diffusion cannot, in itself, account for the current observed asymmetry (40%), and must be primarily primordial and characteristic of the capture mechanism of the Trojans. Finally, we calculate new proper elements for all the numbered Trojans using the semi-analytical approach of Beaugé and Roig (Beaugé, C., Roig, F.V. [2001]. Icarus, 153, 391–415), and compare the results with the numerical estimations by Brož and Rosehnal (Brož, M., Rosehnal, J. [2011]. Mon. Not. R. Astron. Soc. 414, 565–574). For asteroids that were already numbered in 2011, both methods yield very similar results, while significant differences were found for those bodies that became numbered after 2011.Facultad de Ciencias Astronómicas y GeofísicasInstituto de Astrofísica de La Plat

Military tactics during vuelta de obligado´s battle archaeological field and laboratory strategy

En 1845-1846, ingleses y franceses trataron de forzar militarmente los pasos fluviales hacia los territorios del nordeste argentino y el Paraguay, lugares donde pretendían intercambiar mercancías por intermedio de sus políticas de libre comercio. Estas hostilidades contra el gobierno de la Confederación Argentina representaron un proceso que culminó en lo que se conoce como la Guerra del Paraná. La estrategia bélica de los europeos incluyó el bloqueo al Río de la Plata, cuatro batallas y varias escaramuzas. Todas las batallas se libraron en las costas del Rio Paraná: dos de ellas, Vuelta de Obligado y El Tonelero, ocurrieron en la Provincia de Buenos Aires. Dentro de este escenario, la principal táctica defensiva adoptada por la Confederación para impedir el paso de la flota enemiga aguas arriba del río Paraná fue el emplazamiento de baterías en lugares clave como altas barrancas y algunas playas.Desde el año 2000, a través del ProArHEP (UNLu), comenzamos a desarrollar investigaciones y campañas de excavación arqueológica en el sitio Vuelta de Obligado. Así fue que en el lugar hicimos prospecciones, excavamos unos 300 m2, realizamos sondeos y trincheras exploratorias, y llevamos a cabo recolecciones de material en playas. Hasta 2011 excavamos en el área que ocupó la segunda batería. En la actualidad, las excavaciones están centradas en un terraplén, ubicado en el monte, y en el área donde se habría emplazado la primera batería, al mando del Coronel Álvaro Alzogaray. Allí se abrieron nueve cuadrículas de 2 m por 4 m, y una de 3 m por 5 m; y se realizaron varias extracciones de una capa de humus de unos 0,80 m de potencia, que no presenta diferencias internas significativas. Los materiales se encuentran concentrados, principalmente, dentro de una fracción de unos 0,30 m. La secuencia estratigráfica contrasta con la hallada en la segunda batería, donde los materiales arqueológicos fueron localizados en el contacto entre la base de la capa de humus (desde 0,08 m hasta unos 0,20 m) y el techo de la plancha de tosca. El objetivo de este trabajo es presentar la información arqueológica y su análisis en el gabinete. Asimismo, cotejar esa información con la que proviene de los documentos escritos y pictóricos, con el fin de lograr una mejor comprensión del área excavada en la barranca. Las investigaciones realizadas hasta la fecha sugieren, por un lado, que el sector excavado corresponde al piso de ocupación de la primera batería, y por el otro, que los focos de mayor densidad de materiales están relacionados con el modo en que los combatientes de la Confederación dispusieron las estructuras defensivas para protegerse del fuego de la escuadra anglo-francesa durante la batalla.Em 1845-1846, ingleses e franceses tentaram forçar militarmente as travessias fluviais que conduziam aos territórios do nordeste argentino e a Paraguai, onde pretendiam trocar bens por meio de suas políticas de livre comércio. As hostilidades contra o governo da Confederação Argentina representaram um processo que culminou com a chamada Guerra do Paraná. A estratégia bélica dos europeus incluiu o bloqueio do Rio de la Plata, quatro batalhas e várias escaramuças. Todas as batalhas foram travadas nas margens do Rio Paraná: dois delas, Vuelta de Obligado e El Tonelero ocorreram na Província de Buenos Aires. Neste cenário, a principal tática defensiva adotada pela Confederação para impedir a passagem da frota inimiga foi a instalação de baterias em localizações-chave como as altas falésias e algumas praias. Desde 2000, através do Programa Arqueología Histórica y Estudios Pluridisciplinarios (Universidade Nacional de Luján), começamos a desenvolver pesquisas e campanhas de escavação arqueológica no sítio Vuelta de Obligado. Foram realizadas prospecções, sondagens e trincheiras exploratórias, foram escavados cerca de 300 m2 e recolhemos material nas praias. Até 2011 foi escavada a área ocupada pela segunda bateria. Atualmente, as escavações estão centradas em um terrapleno localizado no monte, e na área onde a primeira bateria, comandada pelo coronel Álvaro Alzogaray, teria sido colocada. Nesta última localização foram abertas nove quadrículas de 2 m por 4 m, e outra de 3 m por 5 m; além de várias extrações da camada de húmus de cerca de 0,80 m de espessura que não apresenta diferenças internas significativas. Os materiais estão concentrados, principalmente, dentro de uma fracção de cerca de 0,30 m. A sequência estratigráfica contrasta com a encontrada na segunda bateria, em que os materiais arqueológicos estavam localizados no contato entre a base da camada de húmus (desde 0,08 m até cerca de 0,20 m) e o topo da camada de carbonato de cálcio.O objetivo deste trabalho é apresentar a informação arqueológica e a análise no gabinete. Adicionalmente comparar a informação arqueológica obtida com a dos documentos escritos e pictóricos, a fim de alcançar uma melhor compreensão da área escavada nas falésias. As pesquisas realizadas até agora sugerem, em primeiro lugar, que o setor escavado corresponde à superfície de ocupação da primeira bateria, e, em segundo lugar, que as concentrações de materiais estão relacionadas com a forma em que os combatentes da Confederação colocaram as estruturas de defesa para se proteger do fogo da frota anglo-francesa durante a batalha.In 1845-1846, British and French forces tried to break the fluvial routes into the territories of Northeastern Argentina and Paraguay, where they intended to exchange goods motivated by its free trade policy. These hostilities against the government of the Argentinean Confederation culminated in what is known as the Parana War. The strategy of the combined fleet included blocking the River Plate, four battles and several skirmishes. All battles were fought on the shores of the Parana River, two of them, Vuelta de Obligado and El Tonelero in the Province of Buenos Aires. Within this scenario, the main defensive tactic adopted by the Confederation to prevent the enemy fleet navigate upstream the Parana River was emplacement coastal batteries in key places such as cliffs and beaches. Since 2000, the staff of the Programa Arqueología Histórica y Estudios Pluridisciplinarios (National University of Lujan) began the archaeological research and fieldwork excavations in the Vuelta de Obligado site. In this place, archaeological surveys, test pits and trenches, excavation of around 300 m2, and surface recovery of materials from the beaches, were carried out. Up to 2011 the excavations were focused on the area where the second battery was located. Nowadays, the fieldwork is centered in a mound placed in the woods, and where the first battery under the command of Colonel Álvaro Alzogaray would have been sited. In the latter, nine units of 2 x 4 m, and one of 3 x 5 m, were open. Finds were done in a humus stratum of about 0.8 m thick, which has not show noteworthy internal differences, and the materials were primarily concentrated in a deposit of about 0.3 m. The stratigraphic sequence contrast with that found in the second battery, where the archaeological remains were located in the junction of the humus layer (from 0.08 to0.2 m) and the upper surface of the tosca-rock. The aim of this paper is to present the archaeological information and its analysis in cabinet. Moreover, it seeks to compare this data with that from the written and pictorial sources, in order to achieve a better understanding of the excavated area. Research conducted so far indicate that the excavated sector corresponds to the occupation floor of the first battery. On the other side, they suggest that the places with major concentrations of artifacts are related with the way that Confederation soldiers arranged the defensive structures for its protection from fire of the Anglo-French fleet during the battle.Fil: Ramos, Mariano Sergio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Luján. Departamento de Ciencias Sociales; ArgentinaFil: Umaño Bertola, Milva Ximena. Universidad Nacional de Luján. Departamento de Ciencias Sociales; ArgentinaFil: Ciarlo, Nicolás Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Luján. Departamento de Ciencias Sociales; ArgentinaFil: Pugliese, Agustina Soledad. Universidad Nacional de Luján. Departamento de Ciencias Sociales; ArgentinaFil: Presas, Sebastián. Universidad Nacional de Luján. Departamento de Ciencias Sociales; Argentin

Sitio arqueológico Vuelta de Obligado, San Pedro, provincia de Buenos Aires: Estrategia de investigación y resultados

Este trabajo aborda aspectos de las investigaciones desarrolladas en el sitio arqueológico de Vuelta de Obligado, una de las batallas de la denominada Guerra del Paraná, que enfrentó a la Confederación Argentina con una alianza militar de ingleses y franceses entre 1845 y 1846. Luego de varios años de estudios generales y unas treinta campañas arqueológicas en el sitio, presentamos una síntesis de la estrategia de investigación y los resultados obtenidos hasta la fecha.This paper deals with aspects of the investigations developed in the archaeological site of Vuelta de Obligado, one of the battles of the Paraná War, which confronted the Argentine Confederation with an Anglo-French military alliance between 1845 and 1846. After several years of general studies and at least thirty archaeological campaigns on the site, we present a synthesis of the research strategy and the results obtained to date.Fil: Ramos, Mariano. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Luján. Departamento de Ciencias Sociales; ArgentinaFil: Raies, Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Luján. Departamento de Ciencias Sociales; ArgentinaFil: Leiva, Carolina. Universidad Nacional de Luján. Departamento de Ciencias Sociales; ArgentinaFil: Darigo, Mariano Héctor. Universidad Nacional de Rosario. Facultad de Humanidades y Artes. Escuela de Antropología; Argentina. Universidad Nacional de Luján. Departamento de Ciencias Sociales; ArgentinaFil: Warr, Matias Luciano. Universidad Nacional de Luján. Departamento de Ciencias Sociales; Argentina. Universidad Nacional de Rosario. Facultad de Humanidades y Artes. Escuela de Antropología; ArgentinaFil: Bognanni, Fabián Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Luján. Departamento de Ciencias Sociales; ArgentinaFil: Presas, Sebastián. Universidad Nacional de Luján. Departamento de Ciencias Sociales; Argentina. Universidad de Buenos Aires. Facultad de Filosofía y Letras; ArgentinaFil: Sulich, Keila. Universidad Nacional de Rosario. Facultad de Humanidades y Artes. Escuela de Antropología; Argentina. Universidad Nacional de Luján. Departamento de Ciencias Sociales; ArgentinaFil: Umaño Bertola, Milva Ximena. Universidad Nacional de Luján. Departamento de Ciencias Sociales; Argentina. Secretaría de Cultura de la Nación. Dirección Nacional de Cultura y Museos. Instituto Nacional de Antropología y Pensamiento Latinoamericano; ArgentinaFil: Pugliese, Agustina Soledad. Universidad Nacional de Luján. Departamento de Ciencias Sociales; ArgentinaFil: Dottori, Carolina Andrea. Universidad Nacional de Luján. Departamento de Ciencias Sociales; Argentina. Universidad Nacional de Rosario. Facultad de Humanidades y Artes. Escuela de Antropología; ArgentinaFil: Sportelli, Paola. Universidad Nacional de Luján. Departamento de Ciencias Sociales; Argentina. Universidad Nacional de Rosario. Facultad de Humanidades y Artes. Escuela de Antropología; ArgentinaFil: Scalfaro, Gaston Federico. Universidad Nacional de Luján. Departamento de Ciencias Sociales; ArgentinaFil: Lopez, Augusto. Universidad Nacional de Luján. Departamento de Ciencias Sociales; ArgentinaFil: Gómez, Daniel. Universidad Nacional de Luján. Departamento de Ciencias Sociales; Argentin

Research procedures for Vuelta de Obligado site, San Pedro, province of Buenos Aires

En noviembre de 1845 en Vuelta de Obligado se produce un enfrentamiento terrestre-naval entre fuerzas de la Confederación Argentina y una flota anglo-francesa. Los objetos y estructuras que quedaron como consecuencia del evento, más la posterior influencia de procesos de transformación, dejaron como resultado un sitio arqueológico con varios palimpsestos y recurrentemente saqueado; así la mayoría de los hallazgos son fragmentos y no piezas enteras, ya extraídas por huaqueros. Hasta la fecha excavamos más de 300 m² en distintas áreas, priorizando los “núcleos de la batalla”, aquellos lugares usados con mayor intensidad que dejaron una mayor densidad de restos; recuperamos materiales en transectas ubicadas en playas del río Paraná y realizamos sondeos y prospecciones. El registro arqueológico presenta conjuntos de vidrio, metal, loza, madera, huellas de postes, etc. Aquí exponemos la estrategia respecto del trabajo de campo, gabinete y damos a conocer los resultados luego de más de veinte campañas desarrolladas.Em novembro de 1845 em Volta de Obrigado produzse um confronto terrestrenaval entre forças da Confederação Argentina e uma frota anglo-francesa. Os objetos e estruturas que ficaram como consequência do evento, mais a posterior influência de processos de transformação, deixaram como resultado um lugar arqueológico com vários palimpsestos e recurrentemente saqueado; assim a maioria dos achados são fragmentos e não peças inteiras, já extraídas por huaqueros. Até a data escavamos mais de 300 m² em diferentes áreas, priorizando os “núcleos da batalha”, aqueles lugares usados com maior intensidade que deixaram uma maior densidade de restos; recuperamos materiais em transectas localizadas em praias do rio Paraná e realizamos sondagens e prospecciones. O registro arqueológico apresenta conjuntos de vidro, metal, loza, madeira, impressões de mastros, etc. Aqui expomos a estratégia respeito do trabalho de campo, gabinete e damos a conhecer os resultados depois a mais de vinte campanhas desenvolvidas.In November 1845, a naval and terrestrial battle between the forces of the Argentinean Confederation and an Anglo-French fleet took place in Vuelta de Obligado, Province of Buenos Aires. The objects and structures which survived after this event, together with the ulterior influence of the formation processes, resulted in an archaeological site characterized by palimpsests. Moreover, this location was under the effects of several looters. Thus, most of the materials located during the archaeological works are fragmented. Up to this date, more than 300 m2 were excavated. The research was performed in different areas of the site, emphasizing the “cores of the battle”, those places used more intensively and where a major density of remains were fund. Archaeological surveys and test pits, as well as recovery of materials, were conducted along the Parana River coast. The archaeological record includes a wide variety of artifacts of glass, metal, ceramic and wood, and post traces carved in the tosca-rock, among others. In this paper, the fieldwork and cabinet research strategy employed in Vuelta de Obligado are discussed. Besides, the results obtained after fifteen years and more than twenty campaigns in this site are presented.Fil: Ramos, Mariano Sergio. Universidad Nacional de Luján; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lanza, Matilde Mabel. Universidad Nacional de Luján; ArgentinaFil: Raies, Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Luján. Departamento de Ciencias Sociales; ArgentinaFil: Helfer, Veronica Lucia. Universidad Nacional de Luján; ArgentinaFil: Bognanni, Fabián Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Lanús; Argentina. Universidad Nacional de Luján; ArgentinaFil: Salerno, Virginia Mariana. Universidad Nacional de Luján; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Leiva, Carolina. Universidad Nacional de Luján; ArgentinaFil: Ciarlo, Nicolás Carlos. Universidad Nacional de Luján; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Darigo, Mariano Héctor. Universidad Nacional de Rosario. Facultad de Humanidades y Artes; ArgentinaFil: Warr, Matias Luciano. Universidad Nacional de Rosario. Facultad de Humanidades y Artes; ArgentinaFil: Dottori, Carolina. Universidad Nacional de Rosario. Facultad de Humanidades y Artes; ArgentinaFil: Alanís, Sandra. Universidad Nacional de Luján; ArgentinaFil: Umaño Bertola, Milva Ximena. Universidad Nacional de Luján; ArgentinaFil: Pugliese, Agustina Soledad. Universidad Nacional de Luján; ArgentinaFil: Presas, Sebastián. Universidad Nacional de Luján; ArgentinaFil: López, Ariel. Universidad Tecnológica Nacional; ArgentinaFil: Sportelli, Paola. Universidad Nacional de Rosario. Facultad de Humanidades y Artes; ArgentinaFil: Gómez, Daniel. Universidad Nacional de Luján; ArgentinaFil: Gómez, Marcelo. Universidad Nacional de Luján; ArgentinaFil: Raño, Julia. Universidad Nacional de Luján; ArgentinaFil: Santo, Carolina. Universidad Nacional de Luján; ArgentinaFil: Milani, María Laura Luciana. Universidad Nacional de Luján; ArgentinaFil: Pousa, Yesica. Universidad Nacional de Luján; ArgentinaFil: Lopez, Augusto. Universidad Nacional de Luján; ArgentinaFil: Rodríguez, Rocío. Universidad Nacional de Luján; ArgentinaFil: Rodríguez, Lucía. Universidad Nacional de Luján; Argentin

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

The dynamical evolution of escaped Jupiter Trojan asteroids, link to other minor body populations

The Jupiter Trojans constitute an important asteroidal population both in number and also in relation to their dynamical and physical properties. They are asteroids located around L₄ and L₅ Lagrangian points on relatively stable orbits, in 1: 1 mean motion resonance with Jupiter. However, not all of them lie in orbits that remain stable over the age of the Solar System. Unstable zones allow some Trojans to escape in time scales shorter than the Solar System age. This may contribute to populate other small body populations. In this paper, we study this process by performing long-term numerical simulations of the observed Trojans, focusing on the trajectories of those that leave the resonance. The orbits of current Trojan asteroids are taken as initial conditions and their evolution is followed under the gravitational action of the Sun and the planets. We built “occupancy maps” that represent the zones in the Solar System where escaped Trojans should be found. We find the rate of escape of Trojans from L₅,  ∼ 1.1 times greater than from L₄. The majority of escaped Trojans have encounters with Jupiter although they have encounters with the other planets too. The median lifetime of escaped Trojans in the Solar System is  ∼ 264, 000 years for L₄ and  ∼ 249, 000 years for L₅. Almost all escaped Trojans reach the comet zone,  ∼ 90% cross the Centaur zone and only L4 Trojans reach the transneptunian zone. Considering the real asymmetry between L₄ and L₅, we show that 18 L4 Trojans and 1₄ L₅ Trojans with diameter D > 1  km are ejected from the resonance every Myr. The contribution of the escaped Trojans to other minor body populations would be negligible, being the contribution from L4 and L5 to Jupiter-family comets (JFCs) and no-JFCs almost the same, and the L₄ contribution to Centaurs and TNOs, orders of magnitude greater than that of L₅. Considering the collisional removal, besides the dynamical one, and assuming that Trojans that escape due to collisions follow the same dynamical behavior that the ones removed by dynamics, we would have a minor contribution of Trojans to comets and Centaurs. However, there would be some specific regions were escaped Trojans could be important such as Asteroids in Cometary Orbits (ACOs), Encke-type comets, Shoemaker-Levy 9-type impacts on Jupiter and Near-Earth objects (NEOs).Instituto de Astrofísica de La Plat

The dynamical evolution of escaped Jupiter Trojan asteroids, link to other minor body populations

The Jupiter Trojans constitute an important asteroidal population both in number and also in relation to their dynamical and physical properties. They are asteroids located around L4 and L5 Lagrangian points on relatively stable orbits, in 1: 1 mean motion resonance with Jupiter. However, not all of them lie in orbits that remain stable over the age of the Solar System. Unstable zones allow some Trojans to escape in time scales shorter than the Solar System age. This may contribute to populate other small body populations. In this paper, we study this process by performing long-term numerical simulations of the observed Trojans, focusing on the trajectories of those that leave the resonance. The orbits of current Trojan asteroids are taken as initial conditions and their evolution is followed under the gravitational action of the Sun and the planets. We built “occupancy maps” that represent the zones in the Solar System where escaped Trojans should be found. We find the rate of escape of Trojans from L5, ∼ 1.1 times greater than from L4. The majority of escaped Trojans have encounters with Jupiter although they have encounters with the other planets too. The median lifetime of escaped Trojans in the Solar System is ∼ 264, 000 years for L4 and ∼ 249, 000 years for L5. Almost all escaped Trojans reach the comet zone, ∼ 90% cross the Centaur zone and only L4 Trojans reach the transneptunian zone. Considering the real asymmetry between L4 and L5, we show that 18 L4 Trojans and 14 L5 Trojans with diameter D > 1 km are ejected from the resonance every Myr. The contribution of the escaped Trojans to other minor body populations would be negligible, being the contribution from L4 and L5 to Jupiter-family comets (JFCs) and no-JFCs almost the same, and the L4 contribution to Centaurs and TNOs, orders of magnitude greater than that of L5. Considering the collisional removal, besides the dynamical one, and assuming that Trojans that escape due to collisions follow the same dynamical behavior that the ones removed by dynamics, we would have a minor contribution of Trojans to comets and Centaurs. However, there would be some specific regions were escaped Trojans could be important such as Asteroids in Cometary Orbits (ACOs), Encke-type comets, Shoemaker-Levy 9-type impacts on Jupiter and Near-Earth objects (NEOs).Fil: Di Sisto, Romina Paula. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Observatorio Astronómico de La Plata - Sede Central; 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: Ramos, Ximena Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Gallardo, Tabaré. Universidad de la República; Urugua