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The intestinal parasites Giardia lamblia and Entamoeba histolytica are major causes of morbidity and mortality associated with diarrheal diseases. Metronidazole is the most common drug used to treat giardiasis and amebiasis. Despite its efficacy, treatment failures in giardiasis occur in up to 5%-40% of cases. Potential resistance of E. histolytica to metronidazole is an increasing concern. Therefore, it is critical to search for more effective drugs to treat giardiasis and amebiasis. We identified antigiardial and antiamebic activities of the rediscovered nitroimidazole compound, fexinidazole, and its sulfone and sulfoxide metabolites. Fexinidazole is equally active against E. histolytica and G. lamblia trophozoites, and both metabolites were 3- to 18-fold more active than the parent drug. Fexinidazole and its metabolites were also active against a metronidazole-resistant strain of G. lamblia. G. lamblia and E. histolytica cell extracts exhibited decreased residual nitroreductase activity when metabolites were used as substrates, indicating nitroreductase may be central to the mechanism of action of fexinidazole. In a cell invasion model, fexinidazole and its metabolites significantly reduced the invasiveness of E. histolytica trophozoites through basement membrane matrix. A q.d. oral dose of fexinidazole and its metabolites at 10 mg/kg for 3 days reduced G. lamblia infection significantly in mice compared to control. The newly discovered antigiardial and antiamebic activities of fexinidazole, combined with its FDA-approval and inclusion in the WHO Model List of Essential Medicines for the treatment of human African trypanosomiasis, offer decreased risk and a shortened development timeline toward clinical use of fexinidazole for treatment of giardiasis or amebiasis.

Abstract Fossilized remains of marine calcifiers constitute the physical basis for reconstructions of both deep ocean and sea-surface temperatures going back millions of years, but paleoclimate records derived from their isotope and trace-element chemistry can be biased by diagenesis. Experiments simulating diagenesis in the presence of an 18O-rich seawater analogue were conducted with modern and 14 Myr old foraminifera (Ammonia sp.) tests to investigate their relative susceptibility to oxygen isotope exchange. The fossilized tests were of exceptional preservation and similar to modern tests in terms of structure and crystalline organization, but had experienced partial loss of embedded organic structures, thus a priori offering fewer preferential pathways for porewaters to penetrate the tests. NanoSIMS imaging revealed that oxygen isotope exchange was pervasive in fossil tests, with isotopic exchange occurring at approximately half the rate of modern tests. The results unequivocally show that fossil biocalcites are metastable and remain more susceptible to isotope exchange than abiotic calcites millions of years after sedimentation and burial.

Alberto Campo Baeza siempre ha defendido la idea de que proyectar es investigar. El autor de este artículo, por su parte, ha elegido un proyecto del arquitecto como caso para analizar esta máxima: la Caja de Granada. No sólo por ser el edificio más grande que ha construido Alberto Campo Baeza, sino también por la complejidad y riqueza de temas que se pueden analizar en él, y que beben de sus precursores. En sus artículos tenemos una fuente para saber qué proceso utiliza para proyectar. Sin embargo, aquí partiremos del análisis de sus cuadernos de dibujos para analizarlo de primera mano. El presente artículo se centrará en la investigación que hay detrás del proyecto de Granada, más exactamente en su genealogía: se verá cómo el caso no puede considerarse aisladamente, porque forma parte de otro proceso de investigación más global.

Con motivo del bicentenario de la llamada «consumación de la independencia» ha tenido lugar en la historiografía mexicana una revisión de las lecturas tradicionales sobre el momento en que se dio la transición desde el antiguo virreinato, pasando por provincia de la monarquía constitucional española, hasta un imperio constitucional independiente (1820-1823). El ciclo conmemorativo, que tuvo 2021 como la fecha central, ha estado marcado por los efectos duraderos de la pandemia, el contexto político y la gama de eventos académicos y publicaciones que han visto la luz. En este trabajo proponemos identificar algunos de los principales aportes para un conocimiento más completo y complejo del periodo. A través de ese repaso pretendemos exponer los temas que han suscitado mayor atención e interés, el enfoque que se ha adoptado para abordarlos, y aquello que se ha tendido a omitir o silenciar. Sin duda, la referencia a las implicaciones que conlleva el uso del término «consumación», como parte de los mitos fundacionales, resulta inexcusable.

Introducción

Abstract Distributed Space Systems (DSS) are gaining prominence in the space industry due to their ability to increase mission performance by allowing cooperation and resource sharing between multiple satellites. In DSS where communication between heterogeneous satellites is necessary, achieving autonomous cooperation while minimizing energy consumption is a critical requirement, particularly in sparse constellations with nano-satellites. In order to minimize the functioning time and energy consumed by the Inter-Satellite Links established for satellite-to-satellite communication, their temporal encounters must be anticipated. This work proposes an autonomous solution based on Supervised Learning that allows heterogeneous satellites in circular polar Low-Earth Orbits to predict their close-approach encounters given the Orbital Elements. The model performance is evaluated and compared in two different scenarios: (1) a simplified scenario assuming Kepler orbits and (2) a realistic scenario assuming Simplified General Perturbations 4 orbital model. The obtained results demonstrate a Balanced Accuracy exceeding 95% when compared to realistic data from an available database. This work represents a promising initial stage in developing an alternative approach within the field of DSS.

This paper describes different analysis methodologies in occupational environments and raw materials. A review is presented of the existing methodologies, the approximations made, some of the constraints involved, as well as the best measurement options for the different raw materials. In addition, the different factors that might affect the precision and accuracy of the results are examined. With regard to the methodologies used for the quantitative analysis of any of the polymorphs, particularly of quartz, the study centres particularly on the analytical X-ray diffraction method. Simplified methods of calculation and experimental separation are evaluated for the estimation of this fraction in the raw materials, such as separation methods by centrifugation, sedimentation, and dust generation in controlled environments. In addition, a review is presented of the methodologies used for the collection of respirable crystalline silica in environmental dust.En el presente trabajo se expondrán las diferentes metodologías de análisis tanto en ambientes laborales como en materias primas. Se hará un repaso de las metodologías existentes, las aproximaciones realizadas, las limitaciones de algunas de ellas, así como las mejores opciones de medida para las distintas materias primas. Asimismo, se hará un examen de los distintos factores que pueden afectar a la precisión y exactitud de los resultados. La metodologías empleadas para el análisis cuantitativo de cualquiera de los polimorfos, especialmente cuarzo, se centrará en la metodología analítica de difracción de rayos X y respecto a la estimación de esta fracción en materias primas, se evaluarán métodos de cálculo simplificados y experimentales de separación, como pueden ser métodos de separación por centrifugación, por sedimentación y por generación de polvo en ambientes controlados. Asimismo se hace una revisión de las metodologías utilizadas para la captación de sílice cristalina respirable en polvo ambiental.

The ceramic tile manufacturing process is energy intensive since it contains several stages in which the product is subject to thermal treatment. The thermal energy used in the process is usually obtained by combustion of natural gas, which is a fossil fuel whose oxidation produces emissions of carbon dioxide, a greenhouse gas. Energy costs account for 15% of the average direct manufacturing costs, and are strongly influenced by the price of natural gas, which has increased significantly in the last few years. Carbon dioxide emissions are internationally monitored and controlled in the frame of the Kyoto Protocol. Applicable Spanish law is based on the European Directive on emissions trading, and the assignment of emissions rights is based on historical values in the sectors involved. Legislation is scheduled to change in 2013, and the resulting changes will directly affect the Spanish ceramic tile manufacturing industry, since many facilities will become part of the emissions trading system. The purpose of this study is to determine current thermal energy consumption and carbon dioxide emissions in the ceramic tile manufacturing process. A comprehensive sectoral study has been carried out for this purpose on several levels: the first analyses energy consumption and carbon dioxide emissions in the entire industry; the second determines energy consumption and carbon dioxide emissions in industrial facilities over a long period of time (several months); while the third level breaks down these values, determining energy consumption and emissions in terms of the product made and the manufacturing stage.El proceso de fabricación de baldosas cerámicas es intensivo en energía, pues comprende varias etapas en las que el producto se somete a un tratamiento térmico. Habitualmente, la energía térmica requerida por el proceso se obtiene por la combustión del gas natural, combustible de origen fósil, cuya oxidación conduce a la emisión de dióxido de carbono, uno de los gases causante del efecto invernadero. Los costes energéticos suponen alrededor de un 15 % del coste de fabricación del producto, y están fuertemente influenciados por el precio del gas natural, que en los últimos años ha sufrido un importante incremento. Las emisiones de dióxido de carbono son objeto de seguimiento y control a nivel internacional, en el marco del Protocolo de Kioto. En España, la legislación en vigor se basa en la directiva europea sobre el comercio de emisiones, y la asignación de los derechos de emisión se realiza en base a valores históricos en los sectores afectados. A partir de 2013 se producirán cambios en la legislación que afectan de manera importante al sector de fabricación de baldosas español, pues muchas de las instalaciones entrarán a formar parte del sistema de comercio de emisiones. El objetivo del trabajo presentado es conocer cuál es el consumo actual de energía térmica y las emisiones de CO2 en el proceso de obtención de baldosas cerámicas. Para alcanzarlo, se ha realizado un estudio sectorial a diferentes niveles: un primer nivel sectorial, que analiza los consumos y emisiones de todo el sector, un segundo nivel que abarca valores de consumos de gas y emisiones en las empresas durante un periodo de tiempo prolongado (varios meses), y un tercer nivel, que desglosa más estos valores y se distinguen tanto el consumo energético como las emisiones por producto fabricado y por etapa del proceso.

Using numerical simulations, we explore the static and dynamic response of hopfions to an external magnetic field in cylindrical and toroidal nanorings. Results evidence that the nucleation and stability of hopfions are intricately linked to geometry. When including an external field, due to the Dzyaloshinskii–Moriya interaction and the field direction-dependent annihilation mechanism, the hopfion displays distinct behavior under magnetic fields pointing along opposite directions. We have also obtained the spin wave resonance modes of the magnetization patterns nucleated in both nanorings and show the impact of geometry on the suppression of some of them. The interplay between curvature, topology, and magnetization dynamics opens new possibilities toward hopfion-based spin torque oscillator fabrication.

September 2019 saw the most catastrophic floods on the southeast coast of Spain since 1879, leaving fatalities, thousands of people evacuated, and nearly €500 million in compensation. The aim of this work is to characterize the flood exposure, resistance, hazard, and damage in the buildings affected by that event to create an empirical data set as a tool for improving and validating damage models and their transferability to the Valencian Region. For this purpose, we developed and applied a case study methodology in Almoradí, one of the most severely damaged municipalities in Vega Baja County, after the 2019 events. The proposed methodology starts with on-site surveys to collect data, identifying three archetypes based on exposure and resistance features. Then, absolute and relative damage recorded were correlated with the flood depth. Finally, data were mapped using a GIS system. Results show a significant correlation between the recorded flood depth and both relative and absolute damage, which rises to diverse as varying building exposure and resistance characteristics. The methodology presented to characterize direct tangible damage from empirical data may be transferred to any region whose buildings have been affected by floods. However, for damage estimation purposes, the results may be used only in regions with comparable expected flood depths, building exposure and resistance features.

Abstract Background Migrant seasonal agricultural workers face conditions of material vulnerability such as inadequate housing difficulties prevent access to running water supplies. The purpose of this study is to explore the perceptions of professionals involved in the care and support of seasonal migrant agricultural workers, as it relates to water access and water consumption and their impact on these workers’ health, in a context of COVID-19 pandemic. Methods: A qualitative exploratory and descriptive study was conducted in 2021 as part of a larger research project, based on 63 personal semi-structured interviews with professionals who provided support to seasonal migrant agricultural workers in three Spanish autonomous regions. COREQ checklist was used for reporting. The interviews were recorded, transcribed, and imported into ATLAS.ti-9 for an inductive thematic analysis. Results: The results have been structured into two main themes: (1) Accessing and obtaining water; and (2) Health problems related to water consumption. Seasonal migrant agricultural workers experience barriers to obtaining safe water for hygiene, cleaning, food preparation and drinking. The implementation of regulations to reduce COVID-19 transmission resulted in improved hygiene levels in the migrants’ quarters, including access to safe drinking water. Conclusion: This study suggests that water insecurity experienced by migrant seasonal agricultural workers in Spain results from their poor living conditions and causes health problems related to a lack of hygiene and the use of unsafe water. Sustainable solutions are needed beyond the pandemic in order to provide migrant workers with adequate living conditions and ensure their water needs are fulfilled.