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The crystallization process of methane hydrates in a confined geometry resembling seabed porous silica sedimentary conditions has been studied using molecular dynamics simulations. With this objective in mind, a fully atomistic quartz silica slit pore has been designed, and the temperature stability of a methane hydrate crystalline seed in the presence of water and guest molecule methane has been analyzed. NaCl ion pairs have been added in different concentrations, simulating salinity conditions up to values higher than average oceanic conditions. The structure obtained when the hydrate crystallizes inside the pore is discussed, paying special attention to the presence of ionic doping inside the hydrate and the subsequent induced structural distortion. The shift in the hydrate stability conditions due to the increasing water salinity is discussed and compared with the case of unconfined hydrate, concluding that the influence of the confinement geometry and pore hydrophilicity produces a larger deviation in the confined hydrate phase equilibria. [ABSTRACT FROM AUTHOR]

La pandemia originada por el Covid-19 ha marcado a la humanidad. Tristemente, desde 2020 se han mostrado dos caras contradictorias de la humanidad; por un lado, el egoísmo humano cultivado por un sistema económico que vive del individualismo y el materialismo y, por otro, la cara solidaria y humana que ha sido minimizada por los grandes intereses económicos. El resultado de las dos actitudes, al enfrentar la pandemia, dio resultados sociales diferenciales, que se vislumbran en el impacto tanto en la salud como en la mortandad entre los grupos sociales. Este trabajo presenta un análisis de la forma en que un barrio marginal enfrentó a la pandemia por Covid-19 en el estado de Hidalgo, México, donde muestra que, a pesar de las carencias de servicios, el impacto de la pandemia no fue tan alto como se habría esperado

Angiofibroma is a non-encapsulated, highly vascular tumor that usually originates in the nasopharynx. Laryngeal cases of extranasopharyngeal angiofibroma (ENA) are a very rare pathology, especially in children. Only eight ENA laryngeal cases have been described in the literature, and only one of them is a pediatric case. In this report we present an 11-year-old child with epiglottic ENA resected with transoral endoscopic ultrasonic surgery (TOUSS) with review of the literature. Because of reccurrence after five months he underwent re-excision with CO2 laser. Recurrences in ENA are infrequent, but as demonstrated in our case, close endoscopic follow-up is mandatory in this location. Endoscopic hemostatic procedures like TOUSS and CO2 laser ensure bloodless surgery for the management of this type of vascular laryngeal tumors

Objective This study aimed to estimate the incidence of giant cell arteritis (GCA) in Spain and to analyse its clinical manifestations, and distribution by age group, sex, geographical area and season.Methods We included all patients diagnosed with GCA between 1 June 2013 and 29 March 2019 at 26 hospitals of the National Health System. They had to be aged ≥50 years and have at least one positive results in an objective diagnostic test (biopsy or imaging techniques), meet 3/5 of the 1990 American College of Rheumatology classification criteria or have a clinical diagnosis based on the expert opinion of the physician in charge. We calculated incidence rate using Poisson regression and assessed the influence of age, sex, geographical area and season.Results We identified 1675 cases of GCA with a mean age at diagnosis of 76.9±8.3 years. The annual incidence was estimated at 7.42 (95% CI 6.57 to 8.27) cases of GCA per 100 000 people ≥50 years with a peak for patients aged 80–84 years (23.06 (95% CI 20.89 to 25.4)). The incidence was greater in women (10.06 (95% CI 8.7 to 11.5)) than in men (4.83 (95% CI 3.8 to 5.9)). No significant differences were found between geographical distribution and incidence throughout the year (p=0.125). The phenotypes at diagnosis were cranial in 1091 patients, extracranial in 337 patients and mixed in 170 patients.Conclusions This is the first study to estimate the incidence of GCA in Spain at a national level. We found a predominance among women and during the ninth decade of life with no clear variability according to geographical area or seasons of the year.

En este artículo analizamos las construcciones pronominales de sujeto indeterminado del gascón (Romieu, Bianchi 2005), que se caracterizan por la presencia del pronombre se. Estas construcciones podrían considerarse oraciones pasivas y el pronombre se, por su parte, un detransitivizador. Alternativamente, podrían también tipificarse como impersonales de sujeto suprimido (Blevins 2003). Esta es la hipótesis que defendemos aquí, para lo cual mostramos que se trata de construcciones transitivas con un sujeto suprimido que está semánticamente presente y sintácticamente activo. Si esta es, como presumimos, la hipótesis correcta, entonces las impersonales del gascón podrían clasificarse junto a las construcciones con se/si de lenguas románicas como el italiano (Cinque 1988), el catalán (Bartra 2002) o el español (Mendikoetxea 1999; Ormazabal, Romero 2019), sino también junto a las impersonales de lenguas sin afiliación genética como el vasco (Ortiz de Urbina 2003; Fernández, Berro 2021; Berro, Odria, Fernández 2022).

Heating and CO2 enrichment systems can improve yields in intensive greenhouse agriculture Combining both techniques, which are currently applied commercially, can potentially enhance their effect. The CO2 must be separated from the other noxious gases present (such as CO, NOX, and SO2) to avoid them becoming part of the supply. The CO2 is then provided to the greenhouse on demand in the same way as the heating. In this work, we show that an improved food productivity of a pilot-scale greenhouse system combined with CO2 capture by adsorption using activated carbon and heating with alternative fuel. The proposed system's overall performance was evaluated and optimized. The best values were 46.7 g/kg of CO2 storage capacity on the adsorbent bed, 99.99 % removal rate harmful gases from the gas supplied to the greenhouse, CO2 levels of 1851.0 ± 262.8 mg/Nm3 of the CO2 levels in the greenhouse, and an enrichment time of 2.18 ± 0.92 h/day. The system's effective performance over extended periods (November–February) was confirmed and the productivity of a crop species (tomato) was compared to a control, showing an increment of 18 %. The results indicate that this is a valuable option for increasing the crop yield. By integrating this combined system with advanced climate control strategies, it is possible to maximize the CO2 provided per day, leading to higher yields. The system proved to be stable under real pilot-scale conditions over winter periods (four months).

El objetivo de esta investigación es mostrar los resultados del estudio estadístico del desempeño de estudiantes que matriculan el curso de Química General 1 en la sede Interuniversitaria de Alajuela de la Universidad de Costa Rica para las carreras de Ingeniería Mecánica e Ingeniería Industrial. La investigación se lleva a cabo a través de una metodología cuantitativa, con diseño de alcance exploratorio, a lo largo de 10 años (2007-2018), donde se analiza el perfil del alumnado a partir de los datos de sus expedientes académicos. Del estudio se desprende que hay una expectativa de aprobación de 46% la primera vez que se matricula, mientras que alcanza un 70% luego de cursar tres veces la materia. Además, hay un 20% de estudiantes que, durante el periodo de estudio de la investigación, no vuelven a matricular el curso, lo que puede estar relacionado con la deserción de la carrera o cambio de sede. De las variables consideradas, se puede resaltar que las mujeres aprueban el curso en mayor porcentaje que los hombres y, generalmente, con notas más altas. Por otro lado, se encontró que el alumnado de la carrera de Ingeniería Industrial presenta un 15% más de probabilidades de aprobar el curso, frente a los de la carrera de Ingeniería Mecánica. Finalmente, el grupo estudiantil proveniente de colegios subvencionados muestran mejor rendimiento que los provenientes de colegios públicos, privados o de educación abierta. En conclusión, se resalta la importancia que posee para la institución educativa conocer y comprender a profundidad las características del grupo estudiantil que se inscribe en los cursos introductorios de Química General. La identificación y abordaje de las necesidades específicas del estudiantado representa una estrategia fundamental para aumentar el éxito académico, especialmente en aquellos cursos que, de antemano, presentan elevados porcentajes de reprobación. Esta atención a la diversidad y a las particularidades del alumnado contribuirá de manera significativa a la optimización de la experiencia educativa y al fomento de un entorno de aprendizaje en el que el estudiantado tenga la oportunidad de alcanzar su máximo potencial.

Ectopic Cushing’s syndrome (ECS) is a rare disease associated with significant comorbidity. Among the causes of Cushing's syndrome, adrenocorticotropic hormone-producing extrapituitary tumours are rarely reported. This low frequency makes it difficult for the physician to acquire experience in its management. In this report, we aimed to describe the clinical presentation, diagnostic approach and treatment modalities of 12 patients with ECS treated in a single tertiary centre over a 17-year period. Although they can appear in different locations through the neuroendocrine system, lung tumours are the most frequently reported, as it occurs in our series. They can show different levels of aggressiveness and mild to severe clinical course. Therefore, distinguishing Cushing's disease can be challenging and sometimes requires more specific techniques such as invasive tests or no conventional imaging. Treatment includes controlling both hypercortisolism and neoplastic disease, and multidisciplinary management is recommended.