Communities in DSpace
Select a community to browse its collections.
Recent Submissions
Bothrops asper bite and post-traumatic stress disorder in Costa Rica: report of two cases
(2023-08-01) Millán González, Ricardo; Monge Morales, Luis Fernando; De La Cruz Villalobos, Natalia; Bonilla Murillo, Fabián; Gutiérrez, José María
Snakebite envenoming (SBE) is a public health problem of high impact worldwide. The psychiatric consequences of SBE have been poorly documented. Here we present in detail the phenomenology of two clinical cases of Bothrops asper snakebite post-traumatic stress disorder (SBPTSD) in Costa Rica. We suggest that there is a characteristic presentation of SBPTSD and hypothesize that main contributors to the development of this disorder are: the systemic inflammatory response, the repetition of events that put the patient's life at risk and the human innate fear of snakes. Protocols for the prevention, detection and treatment of PTSD in patients who suffer a SBE should be implemented, with at least one mental health care consultation during hospitalization and a 3–5 months follow-up after the discharge.
Evaluación del diseño y efectos del protocolo general para la atención de la migración laboral para la época de las cosechas agrícolas, en cantones de las fronteras norte y sur de Costa Rica, en el período 2020-2023
(2025) Madrigal Brenes, María Angélica; Sandoval Solano, Luana Sofía; Zúñiga Calderón, Ana Ligia
La Evaluación de diseño y resultados del Protocolo general para la atención de la migración laboral para la época de las cosechas agrícolas, en cantones priorizados en Costa Rica, en el período 2020 – 2023 fue un esfuerzo realizado entre enero del 2024 y julio del 2025, con el objetivo de comprender de qué manera el Protocolo se ha constituido como un mecanismo permanente para facilitar la migración laboral y evaluar su valor público desde tres criterios: pertinencia, relevancia y sostenibilidad. Al ser una evaluación formativa, identifica fortalezas y debilidades de la intervención y propone recomendaciones de mejora. La evaluación evidencia que el Protocolo ha sido pertinente para atender las necesidades de los diferentes actores, demostrando contar un diseño flexible y adaptable a los cambios de contexto. Esto lo ha posicionado como una intervención clave en la gestión de flujos migratorios laborales, que ha fortalecido las capacidades del gobierno por medio de la articulación de una respuesta institucional para satisfacer las demandas de fuerza de trabajo que requiere la producción agrícola nacional y transversalizar enfoques de derechos en los procesos migratorios. El Protocolo ha sido relevante y significativo tanto para las personas migrantes como para el sector productivo, no obstante, persisten oportunidades de mejora que pueden ser abordadas para ampliar el enfoque de derechos. Si bien la OIM ha tenido un rol estratégico en el fortalecimiento de esta y otras capacidades, con el nivel de articulación interinstitucional alcanzado y la madurez del diseño, se prevé que los resultados del Protocolo sean sostenibles aún después de finalizada la cooperación.
Shape and deformation of the Pampean flat slab in Argentina
(2025-10-16) Linkimer Abarca, Lepolt; Warren, Linda M.; Chang, Ying; Anderson, Megan L.; Beck, Susan L.; Olsen, Kira G.
The dominant forces shaping the unique geometries of flat slabs are still not fully understood. Knowing how the stress field changes with respect to the shape of the slab allows inferences of the dominant forces acting on the slab. In this study we calculated new models of the slab geometry and the intraslab stress field in the Pampean flat slab region of the Chile-Argentina Subduction Zone (latitude ∼25◦36◦S) where the Nazca Plate subducts together with the aseismic Juan Fernandez Ridge. To build the models, we used a catalogue of 1 059 well-located slab earthquakes recorded by the SIEMBRA and ESP temporary seismic arrays and calculated 411 new focal mechanisms that were analysed together with 407 focal mechanisms from other catalogues. Our results confirmed slab seismicity features such as a reverse dip (i.e. opposite to the subduction direction) of the seismicity band within the flat slab, two bands of descending seismicity and two regions with an absence of earthquakes. These seismicity patterns express the shape of the slab and its hydration state, with more localized slab dehydration along the inland path of the Juan Fernandez Ridge relative to the surroundings. In one of the regions without earthquakes, the slab is most likely continuous and dry, while in the other one the slab is missing, in agreement with previous works that proposed a hole in the slab visible with other methods. A comparison between the stress field and the local slab dip from both our new model and a previous one (Slab2) indicates that the dominant forces acting on the flat slab are the slab pull and the ridge buoyancy. Finally, the shape of the flat slab is controlled by the geologic migration of the Juan Fernandez Ridge, making the flat slab four times wider than the ridge offshore, and by the competing forces of the slab pull and the ridge buoyancy that creates a notable flexure (bulge) resembling the geometry of the outer rise near the trench.
Huygens and π
(2025-11) Villarino, Mark Bertram; Várilly Boyle, Joseph C.
The Dutch scientist Christiaan Huygens refined Archimedes' celebrated geometrical computation of π to its highest point. Yet the rich content of his beautiful treatise "De circuli magnitudine inventa" (1654) has apparently never been presented in modern form. Here we offer a detailed and contemporary development of several of his most striking results. We also make a historical conjecture concerning Archimedes' trisection figure.
The full electroweak interaction: An autonomous account
(2025-02-18) Gracia Bondía, José Mariano; Rehren, Karl Henning; Várilly Boyle, Joseph C.
The precise renormalizable interactions in the bosonic sector of electroweak theory are intrinsically determined in the autonomous approach to perturbation theory. This proceeds directly on the Hilbert-Fock space built on the Wigner unirreps of the physical particles, with their given masses: those of three massive vector bosons, a photon, and a massive scalar (the "higgs"). Neither "gauge choices" nor an unobservable "mechanism of spontaneous symmetry breaking" is invoked. Instead, to proceed on Hilbert space requires using string-localized fields to describe the vector bosons. In such a framework, the condition of string independence of the S-matrix yields consistency constraints on the coupling coefficients, the essentially unique outcome being the experimentally known one. The analysis can be largely carried out for other configurations of massive and massless vector bosons, paving the way towards consideration of consistent mass patterns beyond those of the electroweak theory.