Inevitability of Plate Tectonics on Super-Earths

The recent discovery of super-Earths (masses less or equal to 10 earth-masses) has initiated a discussion about conditions for habitable worlds. Among these is the mode of convection, which influences a planet's thermal evolution and surface conditions. On Earth, plate tectonics has been proposed as a necessary condition for life. Here we show, that super-Earths will also have plate tectonics. We demonstrate that as planetary mass increases, the shear stress available to overcome resistance to plate motion increases while the plate thickness decreases, thereby enhancing plate weakness. These effects contribute favorably to the subduction of the lithosphere, an essential component of plate tectonics. Moreover, uncertainties in achieving plate tectonics in the one earth-mass regime disappear as mass increases: super-Earths, even if dry, will exhibit plate tectonic behaviour.Comment: 13 pages, 2 figures and 1 table; in press in ApJ

Bulk Composition of GJ 1214b and other sub-Neptune exoplanets

GJ1214b stands out among the detected low-mass exoplanets, because it is, so far, the only one amenable to transmission spectroscopy. Up to date there is no consensus about the composition of its envelope although most studies suggest a high molecular weight atmosphere. In particular, it is unclear if hydrogen and helium are present or if the atmosphere is water dominated. Here, we present results on the composition of the envelope obtained by using an internal structure and evolutionary model to fit the mass and radius data. By examining all possible mixtures of water and H/He, with the corresponding opacities, we find that the bulk amount of H/He of GJ1214b is at most 7% by mass. In general, we find the radius of warm sub-Neptunes to be most sensitive to the amount of H/He. We note that all (Kepler-11b,c,d,f, Kepler-18b, Kepler-20b, 55Cnc-e, Kepler-36c and Kepler-68b) but two (Kepler-11e and Kepler-30b) of the discovered low-mass planets so far have less than 10% H/He. In fact, Kepler-11e and Kepler-30b have 10-18% and 5-15% bulk H/He. Conversely, little can be determined about the H2O or rocky content of sub-Neptune planets. We find that although a 100% water composition fits the data for GJ1214b, based on formation constraints the presence of heavier refractory material on this planet is expected, and hence, so is a component lighter than water required. A robust determination by transmission spectroscopy of the composition of the upper atmosphere of GJ1214b will help determine the extent of compositional segregation between the atmosphere and envelope.Comment: Updated the masses and radii of the Kepler-11 system, added Kepler-30b as well in the analysis. Accepted in ApJ, 39 pages, 9 figure

The Interior Dynamics of Water Planets

The ever-expanding catalog of detected super-Earths calls for theoretical studies of their properties in the case of a substantial water layer. This work considers such water planets with a range of masses and water mass fractions (2 to 5 M_Earth, 0.02% to 50% H2 O). First, we model the thermal and dynamical structure of the near-surface for icy and oceanic surfaces, finding separate regimes where the planet is expected to maintain a subsurface liquid ocean and where it is expected to exhibit ice tectonics. Newly discovered exoplanets may be placed into one of these regimes given estimates of surface temperature, heat flux, and gravity. Second, we construct a parameterized convection model for the underlying ice mantle of higher ice phases, finding that materials released from the silicate iron core should traverse the ice mantle on the timescale of 0.1 to 100 megayears. We present the dependence of the overturn times of the ice mantle and the planetary radius on total mass and water mass fraction. Finally, we discuss the implications of these internal processes on atmospheric observables.Comment: 9 page 4 figure

Diseño de sistema de control de optimización ambiental para cultivo hidropónico

La hidroponía es una técnica o método utilizado para cultivar plantas usando soluciones minerales sin suelo agrícola. Las raíces reciben una solución nutritiva equilibrada disuelta en agua con todos los elementos esenciales para el crecimiento de la planta, pueden crecer en una solución única y en medios inertes como arena lavada y perlita o grava. En Colombia el control de variables ambientales para un cultivo suele ser complicado puesto que las condiciones ambientales varían mucho así que la mayoría de los cultivos suelen presentar pérdidas, esto pasa también con los nutriente dado que en las tierras donde se cultivan son limitados y requieren aplicación de abonos para que los cultivos puedan avanzar en la etapa de desarrollo. A través de este proyecto se pretende comprender lo relacionado con el diseño de un control ambiental, con la intensión de poder ofrecer algunas soluciones adecuadas para las necesidades del sector agroindustrial del país, y así poder fomentar una mejora tecnológica significativa para el campo Colombiano. En este proyecto se plantean algunas soluciones desde los conocimientos adquiridos durante el proceso de formación, aplicando protocolos de comunicación inalámbrica, que logran suplir las necesidades de control en el invernadero permitiendo la regulación de tres variables importantes del ambiente cerrado, como son temperatura, humedad y caudal de riego. El objetivo general de este proyecto es diseñar un sistema de control para un cultivo hidropónico; para ejercer control en las variables críticas del ambiente, se establecerá un protocolo de comunicación inalámbrica para la transmisión de datos y la aplicación de una interfaz gráfica para la visualización de los mismos

Paper Session I-B - Space-Based Communications

Current space lift launches on the Eastern and Western Range require extensive ground-based, real-time tracking, communications, and command/control systems. These systems are expensive to maintain and operate and cover only limited geographical areas. Future spaceports will require new technologies to provide greater launch and landing opportunities, support simultaneous missions, and offer enhanced decision support models and simulation capabilities. These ranges must also have lower costs and reduced complexity, while continuing to provide unsurpassed safety to the public, flight crew, personnel, vehicles, and facilities. Commercial and government space-based assets for tracking and communications offer many attractive possibilities to help achieve these goals. Figure 1 demonstrates the primary existing Eastern and Western Range instrumentation sites and a possible future space-based configuration

Sustentabilidad a través de la puesta en valor del patrimonio arqueológico en la comunidad de Rocco, Huanoquite – Paruro – Cusco, 2023

El objetivo que se planteó en el presente estudio fue analizar las características quetiene la sustentabilidad a través de la puesta en valor del patrimonio arqueológico de la Comunidad de Rocco, Huanoquite – Paruro – Cusco, 2022, fue un trabajo detipo aplicado, alcance explicativo, con un enfoque cualitativo, trabajado con el método la hermenéutica y la triangulación, los participantes fueron los pobladores de la comunidad habiéndose elegido a 6 personas quienes son y fueron dirigentes,y al jefe del parque arqueológico a quienes se les aplico una entrevista con 10 preguntas abiertas, al finalizar el análisis del estudio, las conclusiones a las que se arribaron son: que las características de la sustentabilidad en la Comunidad de Rocco, a través de la puesta en valor del patrimonio arqueológico, por el momento se presentan prácticamente nulas sin embargo con una necesidad urgente de ser consideradas y aplicadas en sus tres ámbitos, tanto por parte de las autoridades como de los pobladores, dichas características enmarcadas en los ejes económico,ambiental y social, permitirán que la comunidad pueda proyectarse y afrontar de mejor manera su presente y futuro

PuoBERTa: Training and evaluation of a curated language model for Setswana

Natural language processing (NLP) has made significant progress for well-resourced languages such as English but lagged behind for low-resource languages like Setswana. This paper addresses this gap by presenting PuoBERTa, a customised masked language model trained specifically for Setswana. We cover how we collected, curated, and prepared diverse monolingual texts to generate a high-quality corpus for PuoBERTa's training. Building upon previous efforts in creating monolingual resources for Setswana, we evaluated PuoBERTa across several NLP tasks, including part-of-speech (POS) tagging, named entity recognition (NER), and news categorisation. Additionally, we introduced a new Setswana news categorisation dataset and provided the initial benchmarks using PuoBERTa. Our work demonstrates the efficacy of PuoBERTa in fostering NLP capabilities for understudied languages like Setswana and paves the way for future research directions.Comment: Accepted for SACAIR 202