Elimination of sulfates from wastewaters by natural aluminosilicate modified with uric acid

Natural aluminosilicate activated by a heat/acid treatment, followed by modification with uric acid was used to remove sulfates for treatment of wastewater effluent. Natural aluminosilicates were studied in every stage of the modification (namely activation, modification with uric acid, and after sulfates absorption) by scanning electron microscopy (SEM), spectroscopy X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), surface area (BET), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and Z potential. More than 60% of the initial concentration of sulfates (500 mg/l) was removed with the natural aluminosilicate modified with uric acid. Absorption isotherms rendered a mechanism with contributions from both Langmuir and Freundlich mechanisms. This study opens the path for the use of natural and abundant local material to remove sulfates using a modifier already present in wastewater effluents as contaminant

Pancreatic metastases from renal cell carcinoma. Postoperative outcome after surgical treatment in a Spanish multicenter study (PANMEKID)

Background: Renal Cell Carcinoma (RCC) occasionally spreads to the pancreas. The purpose of our study is to evaluate the short and long-term results of a multicenter series in order to determine the effect of surgical treatment on the prognosis of these patients. Methods: Multicenter retrospective study of patients undergoing surgery for RCC pancreatic metastases, from January 2010 to May 2020. Variables related to the primary tumor, demographics, clinical characteristics of metastasis, location in the pancreas, type of pancreatic resection performed and data on short and long-term evolution after pancreatic resection were collected. Results: The study included 116 patients. The mean time between nephrectomy and pancreatic metastases' resection was 87.35 months (ICR: 1.51-332.55). Distal pancreatectomy was the most performed technique employed (50 %). Postoperative morbidity was observed in 60.9 % of cases (Clavien-Dindo greater than IIIa in 14 %). The median follow-up time was 43 months (13-78). Overall survival (OS) rates at 1, 3, and 5 years were 96 %, 88 %, and 83 %, respectively. The disease-free survival (DFS) rate at 1, 3, and 5 years was 73 %, 49 %, and 35 %, respectively. Significant prognostic factors of relapse were a disease free interval of less than 10 years (2.05 [1.13-3.72], p 0.02) and a history of previous extrapancreatic metastasis (2.44 [1.22-4.86], p 0.01). Conclusions: Pancreatic resection if metastatic RCC is found in the pancreas is warranted to achieve higher overall survival and disease-free survival, even if extrapancreatic metastases were previously removed. The existence of intrapancreatic multifocal compromise does not always warrant the performance of a total pancreatectomy in order to improve survival. (C) 2021 The Authors. Published by Elsevier Ltd

Project-based Learning and Its Impact on the Academic Performance of Middle School Students

The adoption of active methodologies in the teaching-learning process allows the main actors of education to transform the classroom into scenarios of real experiences of learners. This research aims to analyze the Project-Based Learning methodology and its impact on the academic performance of middle school students. In this research, several methods were applied, including the qualitative documentary bibliographic review, the inductive-deductive method, allowing to identify the characterization of project-based learning, in addition, the academic results of the students of basic secondary of the Educational Unit “Aurelio Salazar”. As result, it was obtained that Project-Based Learning is an active methodology of current education where the teaching process is innovated, the academic performance of 62 students who attended the 2020-2021 school year was analyzed

OBTENCION DEL ÓXIDO CERÁMICO (Y 0,8 Ca0,2) Ba2Cu3O7 POR EL METODO SOL-GEL

On the base of the ceramic superconductor YBa2Cu307 obtained by SOL-GEL process whose critic temperature reached was 92 K. A new doped structure has been synthesized with calcium, in which the Ytrio has been replaced by the calcium in stoichiometry proportion Y:Ca = 0,8: 0,2 . The precursors obtained with the help of oxalate stoichiometry have been modified with calcium nitrate. The obtained matrize was treated thermally 860 ºC and 880 ºC. The characterization has been carrie through the technique of X Rays Diffraction obtained showed that the obtained materials present a high crystalline grade and a good correspondence in their crystalline structures corresponding to each superconductivity phase.Sobre la base del cerámico superconductor YBa2Cu307 obtenido por el proceso SOL-GEL cuya temperatura critica alcanzada fue 92 K, se ha sintetizado una nueva estructura dopada con calcio,en la que el Ytrio fue reemplazado por el calcio en proporción estequiométrica Y:Ca = 0,8: 0,2. Los precursores obtenidos a base de oxalatos fueron modificados estequiométricamente con nitrato de calcio, la matriz obtenida fue tratada térmicamente entre 860 ºC y 880 ºC. La caracterización se ha llevado a cabo a través de la técnica de Difracción de Rayos X obteniéndose superconductores que presentan un alto grado de cristalinidad y una buena corresponde ncia en sus estructuras cristalinas y la fase superconductora

Anales de Edafología y Agrobiología Tomo 35 Número 5-6

2019-08.- CopyBook.- Libnova.- Biblioteca ICA.Evolución de las propiedades física:; en suelos de prados naturales, por S. Cuadrado Sánchez y A. Blanco de Pablos (con la colaboración técnica de l. Hernández Pombero).-- Distribución y .características de los suelos canarios. Isla de La Palma, por J. J. Bravo Rodríguez, E. Fernández Caldas y F. Monturiol.-- Medida de la capacidad reductora de raíces de maíz, por F. Costa, A. M. Pujalte y O. Carpena.-- Estudios sobre la resistencia del castaño a la enfermedad de la «tinta». Efectos fungitóxicos de algunos compuestos fenólicos de C. mollisima, por M. R. Nimo y E. Vieitez.--Efectos de la evolución de diferentes fosfatos cálcicos sobre el crecimiento y el estado de nutrición del Rye-Grass, por C. Mazuelos, P. de Arambarri, L. Catalina y L. Madrid.-- Contribución al estudio de la capacidad total de cambio de suelos mediante diversos métodos analíticos, por J. A. Egido, A. García Rodríguez y J. F. Gallardo.-- Efecto de la utilización del azufre como fertilizante por vía foliar en judía, por C. Lluch, M. Gómez y J. Olivares.-- Tipos de suelos desarrollados sobre las serpentinas de la Sierra de Carratraca (Málaga), por A. García, M. Delgado y J. Aguilar.-- Uso de herbicidas en la implantación de praderas, por J. Segura, R. Fábregas y E. Vieitez.-- Carácter anfótero de la superficie del óxido de titanio (anatasa), por J. Contejo y H. P. Boehm.-- Estudios sobre la resistencia de Lolium perenne L. al Dalapón (2,2-dicloropropionato sódico). I. Efectos bajo las condiciones de campo, por J. Segura, E. Vieitez y R. Fábregas.-- Estudio de la adsorción de aminoácidos, péptidos y proteínas en minerales de arcilla, por M. l. Tellería.-- Real Decreto J361/1976, de 18 de junio, por el que se suprimen las SecretaríasGenerales de la División de Ciencias Matemáticas, Médicas y de la Naturaleza, y del Patronato de Investigación Científica y Técnica Juan de la Cierva, asumiendo sus funciones la Secretaría General del C. S. I. C.-- Real Decreto 1380/1976, de 18 de junio, por el que cesa don Octavio Carpena Artés como Secretario general del C. S. l. C.-- Real Decreto 1381/1976, de 18 de junio, por el que se nombra Secretario general del C. S. I. C. a don Jaime Suárez Alvarez.-- Nombramiento de Vicesecretarios del C. S. I. C.-- Nombramiento del Pro f. Lucena Conde.-- Nombramiento del Pro f. Rivas Goday.-- Nombramiento del Prof. Rivas-Martínez.- Cese del Vicedirector de la Estación Experimental de Aula Dei.-- Variaciones en los Centros.-- Viajes al extranjeros.-- Reunión del Consejo Ejecutivo de la Fundación Europea de la Ciencia.-- Seminario sobre Prioridades de Investigación.-- Grupo de Prioridades del ESRC (Comité de los Consejos de Investigaciones Científicas Europeos).-- BibliografíaPeer reviewe