Study of the increase in bending stiffness on timber beams reinforced with composite materials

It is common to find structures that need to be reinforced due to deterioration or because the function of the building changes. The economic cost involved in these forms of interventions is considerable. Therefore, it is interesting to progress in the existing strengthening techniques and the study of new reinforcement systems. This paper analyses the behaviour of timber beams reinforced with carbon and basalt fiber composite materials. The main objective of this study is to test the stiffness increase produced by the carbon and basalt FRP on reinforced beams. The results show the stiffness increase produced by the different types of reinforcement

Source apportionment of ultrafine and fine particles in Huelva industrial city

Comunicación presentada en: 2012 European Aerosol Conference (EAC-2012), B-WG01S2P30, celebrada del 2 al 7 de septiembre de 2012 en Granada

Estudio de la resistencia de vigas de madera reforzadas con FRPs de tejidos unidireccionales y bidireccionales de fibra de carbono

En este trabajo se realiza un estudio experimental del comportamiento de veinte vigas de madera aserrada de pino silvestre para uso estructural, de dimensiones 155x75x1090mm y reforzadas con materiales compuestos de fibra de carbono. La procedencia de la madera es el aserradero de Valsaín. Los ensayos se han realizado en el Laboratorio de Materiales de Construcción de la Escuela Universitaria de Arquitectura Técnica de Madrid con una máquina de ensayos Universal. El objetivo del trabajo es el análisis del comportamiento a flexión de las piezas ensayadas reforzadas con materiales compuestos de fibra de carbono realizados con tejidos unidireccionales y bidireccionales. De las veinte vigas ensayadas nueve fueron sin reforzar y el resto se reforzaron con el refuerzo en forma de ?U?, adhiriendo el material compuesto a la cara inferior y los laterales de las vigas, hasta una altura de la mitad del canto. Para la realización de los FRP se han empleado tejidos de fibra de carbono unidireccionales y bidireccionales. El gramaje de los tejidos unidireccionales es de 300gr/m2 y se ha aplicado en una capa. Los tejidos bidireccionales utilizados tienen dos gramajes distintos, 160gr/m2 y 210gr/m2. Éstos últimos se han aplicado en una y en dos capas. Las nueve vigas ensayadas sin reforzar han servido como testigo para analizar el aumento de la capacidad de carga de las vigas reforzadas. A partir de los datos facilitados por el software se asociado a la máquina de ensayos se trazaron los gráficos carga-desplazamiento, con el fin de analizar las cargas máximas de rotura alcanzadas, desplazamientos y rigidez de las piezas. Posteriormente se realiza un análisis analítico hallando los valores medio de las cargas de rotura y los desplazamientos, realizando una comparación entre los datos obtenidos para las vigas sin reforzar y las reforzadas con los distintos sistemas. En las conclusiones se presentan los resultados del análisis realizado, estudiando el incremento de la capacidad de carga de las vigas reforzadas con respecto a las no reforzadas, y comparando entre sí el funcionamiento de los refuerzos aplicados

Molecular characterization of autophagic and apoptotic signaling induced by sorafenib in liver cancer cells

Sorafenib is the unique accepted molecular targeted drug for the treatment of patients in advanced stage of hepatocellular carcinoma. The current study evaluated cell signaling regulation of endoplasmic reticulum (ER) stress, c-Jun-N-terminal kinase (JNK), Akt, and 5′AMP-activated protein kinase (AMPK) leading to autophagy and apoptosis induced by sorafenib. Sorafenib induced early (3–12 hr) ER stress characterized by an increase of Ser51P-eIF2α/eIF2α, C/EBP homologous protein (CHOP), IRE1α, and sXBP1, but a decrease of activating transcription factor 6 expression, overall temporally associated with the increase of Thr183,Tyr185P-JNK1/2/JNK1/2, Thr172P-AMPKα, Ser413P-Foxo3a, Thr308P-AKt/AKt and Thr32P-Foxo3a/Foxo3a ratios, and reduction of Ser2481P-mammalian target of rapamycin (mTOR)/mTOR and protein translation. This pattern was related to a transient increase of tBid, Bim EL, Beclin-1, Bcl-xL, Bcl-2, autophagy markers, and reduction of myeloid cell leukemia-1 (Mcl-1) expression. The progressive increase of CHOP expression, and reduction of Thr308P-AKt/AKt and Ser473P-AKt/AKt ratios were associated with the reduction of autophagic flux and an additional upregulation of Bim EL expression and caspase-3 activity (24 hr). Small interfering-RNA (si-RNA) assays showed that Bim, but not Bak and Bax, was involved in the induction of caspase-3 in sorafenib-treated HepG2 cells. Sorafenib increased autophagic and apoptotic markers in tumor-derived xenograft model. In conclusion, the early sorafenib-induced ER stress and regulation of JNK and AMPK-dependent signaling were related to the induction of survival autophagic process. The sustained drug treatment induced a progressive increase of ER stress and PERK-CHOP-dependent rise of Bim EL, which was associated with the shift from autophagy to apoptosis. The kinetic of Bim EL expression profile might also be related to the tight balance between AKt- and AMPK-related signaling leading to Foxo3a-dependent BIM EL upregulation.Ministerio de Economía y Competitividad BFU2016‐75352‐PInstituto de Salud Carlos III PI15/00034, PI13/ 00021, PI16/00090, PI14/01349Ministerio de Educación FPU16/05127, FPU12/01433, FPU13/01237Junta de Andalucía CTS-6264, PI-00025-2013, PI-0127-2013, PI-0198-201

Cambios temporales en el origen de la materia orgánica en las marismas del Río Miño (NW Península Ibérica) mediante marcadores lipídicos. Temporal changes in the organic matter sources in the Minho River tidal marshes (NW Iberian Península): A lipid biomarker approach.

[EN]: The lipid biomarker distribution in a sediment core fromMinho river tidal-marshes (NW Iberian Peninsula) was studiedusing gas chromatography-mass spectrometry (GC/MS) in order to evaluate changes in the sources and distribution of organic matter (OM) in the estuary during the last centuries. The distribution of terrestrial and phytoplankton biomarker inventory reflected an heterogeneous mixture of OM from marine and terrestrial sources. Lignin derived phenols, triterpenoids and long chain n-alkanes with an odd number of carbons are indicators of soil-and vascular plant-derived continental OM, being more abundant on the topmost sections of the core. In addition, a conspicuous contribution from plankton-derived OM (e.g. short chain fatty acids and alcohols, phytosterols) is observed in the deepest sections of the core. However, in general the lipid biomarker assemblage found indicate the existence of a complex input of organic matter (OM) to this estuarine area, from both river run-off and marine depositions. Temporal variations observed could also be attributed to terrigenous contributions after flooding events from Miño river, although a differential degradation of individual biomarkers should not be neglected when interpreting biomarker assemblages in this geodynamically active environment. [ES]: Con el objetivo de evaluar las variaciones en las fuentes y distribución de la matería orgânica (MO) durante los últimos siglos, se estudia la distribución de biomarcadores lipídicos en una secuencia sedimentaria de las marismas del río Miño (NW Península Ibérica) mediante Cromatografía de Gases¿Espectrometria de Masas (CG/MS) . La distribución de biomarcadores terrestres y marinos muestra una mezcla heterogénea de MO con diferente orígen. Los fenoles derivados de la lignina, triterpenoides y n-alcanos de cadena larga con número impar de carbonos proceden de plantas superiores, indicadores de MO de origen continental , se encuentran com mayor abundancia en las secciones superiores del sondeo. Los lípidos derivados del plancton marino (ej., acidos grasos y alcoholes de cadena corta, fitosteroles) se encontraron con mayor abundancia relativa en las secciones mas profundas del sondeo. Sin embargo, la distribución global de los biomarcadores lipídicos estudiados muestra la complejidad de las fuentes de MO en este estuario, y que incluye las descargas del río y deposiciones de sedimentos marinos. Algunas variaciones observadas pueden deberse a contribuciones de MO terrígena debidas a descargas elevadas procedentes del río Miño. No obstante, a la hora de interpretar los cámbios observados en la distribución de determinados biomarcadores en este ambiente geodinámicamente activo, se debe tener en cuenta la posible ocurrencia de fenómenos de degradación preferencial o selectiva en el sedimento.Peer Reviewe

Determination of refractory organic matter in marine sediments by chemical oxidation, analytical pyrolysis and solid-state 13C nuclear magnetic resonance spectroscopy

Seeking to quantify the amount of refractory organic matter (ROM), which includes black carbon-like material (BC), in marine sediments, we have applied a two-step procedure that consists of a chemical oxidation with sodium chlorite of the demineralized sediments followed by integration of the aromatic C region in the remaining residues by solid-state 13C nuclear magnetic resonance (NMR) spectroscopy. The efficacy for lignin removal was tested by analytical pyrolysis in the presence of tetramethyl ammonium hydroxide (TMAH). Riverine, estuarine and offshore marine sediment samples were collected from the southwest Atlantic coast of Spain, a site of geological and environmental interest. Measured contents of BC-like material ranged between 3.0 and 45.7% of the total organic carbon. Greater relative BC contents were found in riverine sediments close to urban areas, which show an elevated input of anthropogenic organic material. The contents of BC-like material in offshore marine sediments (5.5–6.1%) were similar to those previously reported for these kinds of samples. However, NMR and pyrolysis-GC/MS of the isolated ROM reveals that abundant refractory aliphatic organic material remains in most of the marine samples after chlorite oxidation. We suggest that this pool of aliphatic carbon may play an important role as a stable carbon pool within the global C cycle.The Spanish Ministry of Education provided financial support for this research (fellowship BES-2003-1900 and project CGL2006-12730-C03-C01).9 páginas, 3 figuras, 6 tablas, 38 referencias.-- [email protected] reviewe

Factors involved in soil organic matter stabilization in Peruvian Amazonian soils (Ucayali region) and the molecular composition of extractable lipids

Poster E1012b presentado en el 27th International Meeting on Organic Geochemistry September 13–18, 2015, Prague, Czech RepublicAmazonian ecosystems are considered important sinks for atmospheric CO2 on Earth. It is therefore desirable to preserve their biodiversity and productivity. In this communication an assessment of the influence of different agro-forestry practices on soil C storage in representative ecosystems from the Peruvian Ucayali region is approached by analyzing the soil lipid fraction. In fact, this organic matter fraction is an important source of analytical surrogates of soil C stabilization and accumulation processes (Naafs at al., 2004; Poulenard et al., 2004; Rumpel et al., 2004). Top (0–20 cm) and subsoil (20–40 cm) samples were taken from the Amazonian Ucayali region (Pucallpa, Perú), ranging from recent alluvial soils in muddy zones of riverside areas (wetlands referred to as ‘mud’, ‘beach’ and low ‘restinga’ soils) to more developed soils located in medium and higher riverine terraces, as well as in hills. The lipid fraction was Soxhlet extracted with a mixture of ichloromethane:methanol (2:1 by vol.), saponified and divided into neutral and acid subfractions. The acid fractions were then sequentially methylated and silylated prior to the chromatographic analysis (González-Vila et al., 2003). Neutral and acid sub-fractions were separated and the major compounds were identified by gas chromatography-mass spectrometry using an HP G1800A GCD System (electron impact detector at 70 eV) equipped with a DB-5 fused silica capillary column (30 m × 0.32 mm i.d., film thickness 0.25 µm) and using He as carrier gas at a flow rate of 1.5 mL min-1. The chromatographic oven temperature was programmed to increase from 40 to 100 ºC at 30 ºC min-1 and then to 300 ºC at 6 ºC min -1. The values of soil organic matter and lipids ranged from 25.8 to 5.8 g kg-1, and from 5.2 to 0.2 g kg-1, respectively. This variability as well as the differences in lipid molecular composition could suggest differences in the soils’ use and management practices (Van Bergen et al.,1996). The main families of signature lipids detected in the soil extracts were n-alkanes, linear isoprenoids, cyclic alkanes, n-fatty acids, branched fatty acids, unsaturated fatty acids, hydroxyacids, n-alcohols, ketones, polycyclic hydrocarbons and sterols. Very significant differences in qualitative and quantitative lipid composition were found in terms of soil depth. This effect was more pronounced in the soils from the riverine high terraces devoted to agro-forestry practices (Figs. 1 and 2). In addition, lipidic compounds of high molecular weight (i.e., di- and triterpenes) were detected as regular components of the free lipid fractions from the different ecosystems (wetlands, terraces and hills) reflecting specific vegetation and soil-use influences. Xenobiotic compounds (naphthenic acids) detected within the unresolved chromatographic ‘hump’ (highly unresolved mixture of cyclic or branched hydrocarbons) were also observed, indicating anthropogenic contamination by mineral oils. Likewise, dialkyl phthalates (Phth) from plasticizers were also detected.Projects CGL2012-38655-C04-01 and CGL2008-04296 and fellowship BES-2013-062573 given to N.T.J.M by the Spanish Ministry of Economy and Competitiveness. Dr. J.M.R. is the recipient of a fellowship from the JAE-Doc subprogram financed by the CSIC and the European Social Fund.Peer Reviewe

Fire impact and assessment of post-fire actions of a typical Mediterranean forest from SW Spain

Poster presentado en lal EGU General Assembly 2015, held 12-17 April, 2015 in Vienna, Austria. id.2248Wildfires may cause significant changes in soil physical and chemical properties. In addition, soil organic matter (SOM) content and chemical properties are usually affected by fire. Fire impacts may negatively affect soil health and quality, and induce or enhance runoff generation and, thereby, soil erosion risk and cause damages to the habitat of species. This fact is especially dramatic in Mediterranean ecosystems, where forest fires are a frequent phenomenon and restoration strategies are a key issue. The goals of this study are to determine: i) the immediate effects of fire on soil properties, including changes occurred in the quantity and quality of SOM and ii) the effect of post-fire actions on soil properties. In August 2012, a wildfire affected a forest area of approx. 90 ha in Montellano (Seville, SW Spain; longitude 37.00 º, latitude -5.56 º). This area is dominated by pines (Pinus pinaster and Pinus halepensis), and eucalypts (Eucaliptus globulus) with a Mediterranean climate. Dominant soil types are Rendzic Leptosols and Calcaric Haplic Regosols. It is a poorly limestone-developed soil (usually swallower than 25 cm). Four soil subsamples were collected 1 month and 25 months after fire within an area of approximately 200 m2. Subsamples were mixed together, homogenized, air-dried, crushed and sieved (2 mm). One control sample was collected in an adjacent area. The litter layer was removed by hand and studied separately. Branches, stems, bushes and plant residues on the fire-affected area were removed 16 months after the fire using heavy machinery as part of the post-fire management. The present research focuses on the study of the elemental composition (C, H and N) and physical properties (pH, water holding capacity, electrical conductivity) of bulk soil samples, and on the spectroscopic analysis (FT-IR, 13C NMR) and analytical pyrolysis data obtained from bulk the oils and from the humic acid fraction. immediate effects of fire, including the charring of vegetation and litter, as the input of charred residues may contribute to increase the total amount of soil organic matter. The post-fire removal of vegetation probably contributed to an additional loss of soil material due to an increase of the erosion risk. In addition, preliminary results point out that the burnt soil is not being recovered to the pre-fire conditions at a molecular level neither in the elemental composition. Results of this study will constitute a valuable tool for stake holders and decision makers to avoid additional alterations caused by post fire management of fire affected forests.Peer Reviewe

Evolución de los modelos docentes de futuros profesores de economía de secundaria, a través de la metáfora

A través de un cuestionario de preguntas abiertas, este estudio analiza la evolución de las metáforas personales de una muestra de profesores en formación de la especialidad de Economía del Máster Universitario en Formación del Profesorado en Educación Secundaria, durante el curso 2012/2013. Para el análisis se han adaptado las cuatro categorías de Leavy, McSorley y Boté (2007): conductistas-transmisivas, cognitivas-constructivistas, situadas y autorreferenciadas. Los resultados indican que la mayoría de los participantes fueron capaces de conceptualizar sus roles en términos de metáforas. Al comparar las metáforas, antes y después de las prácticas de enseñanza, se produce una evolución progresiva de las metáforas conductistas-transmisivas a cognitivas-constructivistas y situadas. Para los profesores en formación, la reflexión sobre sus propias metáforas, se ha mostrado como una buena herramienta para hacerlos conscientes de sus concepciones y de sus roles docentes, y para iniciar cambios en los mismos hacia modelos didácticos más centrados en el alumnado.Using the responses to open questions, this study analyzes the evolution of personal metaphors of a sample of prospective secondary economics teacher during their Master's degree course in Secondary Teacher Education during the 2012/2013 academic year. The study applied an adaptation of the four categories of Leavy, McSorley & Boté (2007): transmissive/ behavioral, cognitive/constructivist, situated and self-referential. The results indicate that most of the prospective teachers were able to conceptualize their roles in the form of metaphors. Comparing metaphors before and after teaching practice, a progressive evolution occurs from transmissive-constructivist metaphors to cognitive-behavioral and situated metaphors. For preservice teachers, reflecting on their own metaphors, it has proven to be a good tool to make them aware of their conceptions and their teaching roles, and to initiate changes in them towards more focused teaching models in students

Morfometría macroscópica del cuerpo lúteo de vacas cebú gestantes y no gestantes en el trópico colombiano

The objective of the study was to determine the volume, weight, measures, ovarian location and shape of the corpus luteum of pregnant and non - pregnant cows from zebu cows of the Colombian tropics. 528 reproductive tracts were collected; 264 pregnant and 264 non-pregnant of cows benefited at the local slaughterhouse in Monteria, Córdoba, Colombia. The period of collection of the samples was extended for three months. After collection of each reproductive tract, the ovaries were separated, identified as right and left, weighed and measured. Then the drawing of the location of the corpus luteum was performed on the ovary according to the anatomical planes previously established in the corresponding form. Subsequently the corpus luteum was removed to perform their measurements, weighings and visualization of their shape. There were statistical differences between the locations of the corpus luteum in the ovary: Anterior pole, posterior pole, free edge, upper face and lower face (p?0.05). The weight and volume of gestational corpus luteum was greater by 30 and 27.9% than the corpus luteum of non-pregnant cows. The predominant form por shape of the corpus luteum in both pregnant and non-pregnant cows was oval, then pyramidal and finally rounded. No gestation was observed contralateral to the location of the corpus luteum.El objetivo del trabajo fue determinar el volumen, peso, medidas, ubicación ovárica y forma del cuerpo lúteo de vacas gestantes y no gestantes de vacas del trópico colombiano. Se recolectaron 528 tractos reproductivos; 264 gestantes y 264 no gestantes de vacas beneficiadas en el frigorífico local de Montería, Córdoba, Colombia. El periodo de recolección de las muestras se extendió por tres meses. Después de la recolección de cada tracto reproductivo se separaron los ovarios, identificándolos como derechos e izquierdos, se pesaron y se midieron. Luego se realizó el dibujo de la ubicación del cuerpo lúteo en el ovario de acuerdo con los planos anatómicos previamente establecidos en el formulario correspondiente. Posteriormente se removieron los cuerpos lúteos para realizar sus medidas, pesajes y visualización de su forma. Hubo diferencias estadísticas entre las ubicaciones del cuerpo lúteo en el ovario: Polo anterior, polo posterior, borde libre cara superior y cara inferior (p?0.05). El peso y volumen del cuerpo lúteo gestacional fue mayor en un 30 y 27.9% que el cuerpo lúteo de vacas no gestantes. La forma predominante del cuerpo lúteo tanto en vacas gestantes como en no gestantes fue la ovalada, luego la piramidal y por último la redondeada. No se observó ninguna gestación contralateral a la ubicación del cuerpo lúteo