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Suarez Pari s R.,KTH Royal Institute of Technology | Montes V.,University of Co rdoba | Boutonnet M.,KTH Royal Institute of Technology | Jaras S.,KTH Royal Institute of Technology
Catalysis Today | Year: 2014

Ethanol and higher alcohols are one of the most interesting alternatives to replace fossil fuels in the transportation sector. Nickel-modified alkali-doped molybdenum sulfide is a potential catalyst for the conversion of syngas to mixed alcohols. In this work, K-Ni-MoS2 catalysts were synthetized by coprecipitation in aqueous solution or in microemulsions, followed by alkali doping. The influence of the preparation route in CO hydrogenation was investigated at 91bar, 340/370°C and GHSV=2000-14,000NmL/hgcatalyst. The catalysts were also characterized by TGA, ICP, XPS, nitrogen adsorption, XRD, SEM-EDX and TEM. The novel microemulsion catalyst outperformed the conventional one, resulting in higher yields of ethanol and higher alcohols. The higher activity and selectivity was attributed to a higher concentration of promoters on the microemulsion catalyst surface, together with a lower degree of crystallinity. © 2014 Elsevier B.V.


Gahete M.D.,Campus Universitario Of Rabanales | Gahete M.D.,University of Co rdoba | Gahete M.D.,Sofia University | Gahete M.D.,CIBER ISCIII | And 32 more authors.
Journal of Endocrinology | Year: 2014

Ghrelin is a 28-amino acid acylated hormone, highly expressed in the stomach, which binds to its cognate receptor (GHSR1a) to regulate a plethora of relevant biological processes, including food intake, energy balance, hormonal secretions, learning, inflammation, etc. However, ghrelin is, in fact, the most notorious component of a complex, intricate regulatory system comprised of a growing number of alternative peptides (e.g. obestatin, unacylated ghrelin, and In1-ghrelin, etc.), known (GHSRs) and, necessarily unknown receptors, as well as modifying enzymes (e.g. ghrelin-O-acyl-transferase), which interact among them as well as with other regulatory systems in order to tightly modulate key (patho)-physiological processes. This multiplicity of functions and versatility of the ghrelin system arise from a dual, genetic and functional, complexity. Importantly, a growing body of evidence suggests that dysregulation in some of the components of the ghrelin system can lead to or influence the development and/or progression of highly concerning pathologies such as endocrine-related tumors, inflammatory/cardiovascular diseases, and neurodegeneration, wherein these altered components could be used as diagnostic, prognostic, or therapeutic targets. In this context, the aim of this review is to integrate and comprehensively analyze the multiple components and functions of the ghrelin system described to date in order to define and understand its biological and (patho)-physiological significance. © 2014 Society for Endocrinology Printed in Great Britain Published by Bioscientifica Ltd.


Morillo J.G.,University of Co rdoba | Marti n M.,University of Co rdoba | Camacho E.,University of Co rdoba | Di az J.A.R.,University of Co rdoba | Montesinos P.,University of Co rdoba
Agricultural Water Management | Year: 2014

The Doñana area in Southwestern Spain has the largest concentration of strawberry producers in Europe. The annual yield, close to 300,000. t, is mainly devoted to the international markets (more than 90%). Due to the high water demand of strawberries and to the environmental concerns of the destination countries, the maximization of water use efficiency is critical for the strawberry sector.Aiming at the efficient water use in the strawberry production, a comprehensive drip irrigation system has been designed, according to precision irrigation principles. The system has been developed based on a three stages methodology. First, the irrigation process carried out by farmers has been assessed to identify inefficiencies in the irrigation system and management. Their performances have been evaluated using indicators such as the Relative Irrigation Supply (RIS), Strawberry Irrigation Water Applied (SWA) and Strawberry Water Footprint Applied (SWFA). The second phase is focused in an accurate irrigation scheduling based in precise crop water requirements estimation and the optimum irrigation pulse design. Finally, the irrigation system has been designed with the prevailing wisdom of meets the needs of the crop in a timely manner and as efficiently and as spatially uniformly as possible. The most appropriate drip irrigation emitters for the particular conditions of the strawberry production in the study area have been selected. The rest of the on-farm irrigation technologies required to control the system have been integrated, including soil water sensors, smart water meters, programmers, electrovalves and weather station. This precision irrigation system has been installed in a commercial strawberry farm during the irrigation season 2013-2014.Also, an application for PC, mobiles and tablets has been developed to provide farmers practical information (e.g. irrigation times) for optimal irrigation scheduling. © 2014 Elsevier B.V.


Go mez N.,University of León | Rosas J.G.,University of León | Cara J.,University of León | Marti nez O.,University of León | And 2 more authors.
Journal of Cleaner Production | Year: 2014

The present study focused on assessing the effect of the temperature (350, 450 and 550 °C) on the pyrolysis performance of several biomasses: olive stone, almond shell, pine wood and olive-tree pruning. First, they were subjected to thermogravimetric and Differential Scanning Calorimetric analyses to determine their thermal decomposition and heat flux. Afterwards, several tests were performed in a pilot plant reactor for char production. Moreover, a characterisation of the pyrolysis products and an assessment of both energy requirements and potentially energy self-sufficient process were performed. Our results show that the process was feasible with low grade pretreated biomass and it would become self-sufficient with the energy from gas and liquid fractions at 350 °C. The analyses of the char samples (proximate, elemental and organic carbon (Corg) analyses) show that almost all of them had features indicating that they were “biochar“, suggesting high stability at higher formation temperatures based on their molar ratios (H/Corg; O/Corg). However, a more detailed characterisation is necessary to assess the quality of char as a soil amendment. © 2014 Elsevier Ltd.


Pereiro N.,University of Vigo | Moyano R.,University of Co rdoba | Blanco A.,University of Co rdoba | Lafuente A.,University of Vigo
Toxicology Letters | Year: 2014

Perfluorooctane sulfonate (PFOS) is a fluorinated compound and a Persistent Organic Pollutant which can disrupt the endocrine system. This work was undertaken to evaluate the possible effects of PFOS exposure on the regulation of corticosterone secretion in adrenal and pituitary glands and at hypothalamic level in adult male rat, and to evaluate the possible morphological alterations induced by PFOS in this endocrine tissue. Adult male rats were orally treated with 0.5, 1.0, 3.0 and 6.0. mg of PFOS/kg/day for 28 days. Corticosterone, adrenocorticotropic hormone (ACTH) and corticotrophin-releasing hormone (CRH) secretion decreased in PFOS-treated rats. After PFOS exposure, relative expression of adrenocorticotropic hormone receptor (ACTHr) and proopiomelanocortin (POMC) genes was increased in adrenal and in pituitary glands, respectively; while relative expression of ACTHr and CRH genes decreased in hypothalamus with the doses of 0.5 and 1.0. mg/kg/day. PFOS treatment increased relative nitric oxide synthase 1 and 2 (NOS1 and NOS2) gene expression in the adrenal gland, and incremented superoxide dismutase activity. PFOS exposure induces a global inhibition of the hypothalamic-pituitary-adrenal (HPA) axis activity, and small morphological changes were observed in adrenal zona fasciculata cells. © 2014 Elsevier Ireland Ltd.

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