RESUMEN
Microplastics (MPs) have been observed in the oceans, fresh waters, karstic water and remote water bodies. However, little is known on groundwater contamination, which is a natural resource of utmost importance for millions of people and is often perceived as a reliable source of water. Moreover, nanofiltration is perceived as a reliable technology to remove contaminants from water. In this study, large sample volumes of a silty-sandy gravel aquifer and the corresponding nanofiltered water were analysed for the presence of MPs (> 20 µm) using Fourier transform infrared (FTIR) microscopy. Concentration in ground water was 8 ± 7 MPs/m3 and increased to 36 ± 11 MPs/m3 in nanofiltered water. All MPs had a maximum Ferret diameter lower than 500 µm. Size distribution of MPs was towards the small size class (20-50 µm). In groundwater, 33% of MPs were detected in the smallest size class (20-50 µm) and 67% in the 50-100-µm-size class. In comparison, around 52% of MPs in nanofiltered water were observed in the 20-50 µm size class. Moreover, 33% of the MPs observed in nanofiltered water were in the 50-100 µm size class and 15% in the 100-500-µm-size class. From a chemical point of view, different plastic polymers were identified in groundwater and in nanofiltered water, such as polypropylene (PP), polyvinyl chloride (PVC), ethylene (vinyl acetate) copolymer (EVA), polyethylene (PE), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA) and other polymer materials (such as polystyrene-based copolymers, vinyl-based copolymers). Fibres were observed in all samples, but only a small number of fibres (near 1%) were identified as PP synthetic fibres in nanofiltered water. Furthermore, no clear difference of fibre concentrations was observed between groundwater (232 ± 127 fibres/m3) and nanofiltered water (247 ± 118 fibres/m3). Groundwater had extremely low levels of microplastics, and although the nanofiltration effectively removes suspended particulate matter, it slightly contaminates the filtered water with MPs.
Asunto(s)
Agua Subterránea , Polivinilos , Contaminantes Químicos del Agua , Humanos , Animales , Microplásticos , Plásticos , Suiza , Hurones , Agua , Polietileno , Polímeros , Monitoreo del AmbienteRESUMEN
Fundamento y objetivo: Se trata de un estudio transversal donde se han determinado los valores de sensibilidad y especificidad del estudio de perfusión miocárdica con 99mTc-Tetrofosmina en protocolo de un día tras estímulo farmacológico con dipiridamol, en una población de mujeres previamente revascularizadas, así como la relación con los territorios vasculares coronarios, tomando como referencia la coronariografía. Pacientes: Se han estudiado con carácter retrospectivo 53 historias clínicas de mujeres sometidas a una prueba de perfusión miocárdica y a una coronariografía de control. Resultados: Los valores de sensibilidad y especificidad para la población fueron de 64,29 por ciento y 75,0 por ciento respectivamente. Por territorio arterial coronario, los valores de sensibilidad y especificidad para la arteria DA fueron de 68,75 por ciento y 75,0 por ciento respectivamente, para la Cx de 37,93 por ciento y 88,89 por ciento, y para la CD de 46,43 por ciento y 60,71 por ciento. Conclusiones: En las mujeres que han sido previamente revascularizadas, la gammagrafía de perfusión miocárdica con 99mTc-Tetrofosmina y dipiridamol en protocolo de un día parece ser una prueba idónea para realizar el seguimiento de pacientes.
Background: This is a cross-sectional study to identify the values of sensitivity and specificity of myocardial perfusion imaging with 99mTc-tetrofosmin one-day protocol after pharmacological stimulation with dipyridamole in a population of women previously revascularized and the relationship of findings to coronary vascular territories, with coronary angiography as a gold standard. Patients We studied retrospectively 53 medical records of women undergoing myocardial perfusion test and control coronary angiography. Results: The sensitivity and specificity for the population were 64.29 percent and 75.0 percent respectively. For coronary artery territory, the values of sensitivity and specificity for the LAD were 68.75 percent and 75.0 percent respectively, for Cx of 37.93 percent and 88.89 percent, and for the RCA 46.43 percent and 60.71 percent. Conclusions: In women who have been previously revascularized, myocardial perfusion scintigraphy with 99mTc-tetrofosmin and dipyridamole in one-day protocol seems to be a suitable test to monitor patients.
Asunto(s)
Humanos , Femenino , Compuestos Organofosforados , Compuestos de Organotecnecio , Corazón , Imagen de Perfusión Miocárdica , Revascularización Miocárdica/métodos , Angiografía Coronaria , Corazón , Corazón , Cuidados Posoperatorios , Dipiridamol/farmacología , Estudios Transversales , Prueba de Esfuerzo , Radiofármacos , Sensibilidad y Especificidad , Valor Predictivo de las PruebasRESUMEN
La absorción del Real Tribunal del Protoalbeitarato1 por la Escuela de Veterinaria de Madrid presenta ciertas singularidades respecto al proceso equivalente en medicina y farmacia. La pugna y hegemonía del Real Tribunal durante casi sesenta años desde la creación de la Escuela de Veterinaria (1792), ha sido estudiada por la historiografía tradicional con una visión centrada fundamentalmente en aspectos veterinarios. En el presente artículo se investigan en detalle los procesos conducentes a la absorción y se pone de manifiesto la relevancia de las motivaciones políticas y su predominio sobre las de carácter técnico, sanitario o profesional. Por ello, se analiza el juego de instituciones y de agentes externos a la veterinaria implicados, en especial destacamos el papel desempeñado por el XV Marqués de Cerralbo (AU)
The absorption of the Real Tribunal del Protoalbeitarato by the Veterinary Science School of Madrid shows several singularities in relation to the equivalent process in medicine and pharmacy.The conflict and the hegemony of the Real Tribunal during almost sixty years from the creation of the Veterinary Science School (1792), has been studied by the traditional historiography with a view fundamentally focused on veterinary aspects. In this article, the process of absorption is investigated in full detail. Also, the relevance of political motivations and their predominance over technical, sanitary or professional motivations are shown. So, the game of institutions and agents which are external to the veterinary science are analysed; specially, the out standing role performed by the XV Marquis of Cerralbo(AU)