939 research outputs found

    Solar/lamp-irradiated tubular photoreactor for air treatment with transparent supported photocatalysts

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    A novel versatile tubular reactor that may use both types of radiation, solar and/or artificial, and different types of suspended or immobilized photocatalysts is proposed. The photocatalytic reactor was evaluated for air treatment at laboratory scale and semi-pilot-plant scale. UV-A transparent immobilized photocatalysts were employed, which allowed an efficient use of radiation. Two different types of photocatalytic modules were tested: (a) TiO2-coated PET monoliths and (b) TiO2-coated glass slides, arranged in monolith-like units with the help of especially designed star-shaped polygonal structures. Both types of units were easy to handle and assured the adequate distribution of the photocatalyst inside the tubular reactor. The efficiency of the photocatalytic system with both solar and artificial radiation to oxidize the H2S contained in an air stream was demonstrated at the laboratory roof and in the treatment of real air of a wastewater treatment plant located in Madrid (Spain). As a consequence of the chemical nature of the pollutant, the photocatalytic activity decayed over time due to the accumulation of sulfate on the surface, but easy regeneration of the exhausted photocatalyst was achieved by washing with water.The authors would like to acknowledge Comunidad de Madrid (DETOX-H2S S-0505/AMB/0406), Ministerio de Ciencia e Innovación (CTM2008-06876-C02-01) and AECID for financial support and Gloria Simón Naranjo and Francisco Sánchez Moreno for the help with the reactor set-up.Peer reviewe

    Compositional mapping by Z-contrast imaging

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    This research was sponsored by the Office of Basic Energy Sciences, Materials Sciences and Engineering Division, U.S. Department of Energy (SJP, MV), by the Spanish MCI (projects CONSOLIDER INGENIO 2010 CSD2009-00013 andTEC2008-06756-C03-02/TEC,) and the Junta de Andalucía (PAI research’s groups TEP-120 and TIC-145; project P08-TEP-03516).Peer Reviewe

    Photocatalysis for Continuous Air Purification in Wastewater Treatment Plants: From Lab to Reality

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    The photocatalytic efficiency of TiO2–SiMgOx plates to oxidize H2S was first evaluated in a flat laboratory reactor with 50 mL min–1 synthetic air containing 100 ppm H2S in the presence of humidity. The use of the photocatalyst-adsorbent hybrid material enhanced the photocatalytic activity in terms of pollutant conversion, selectivity, and catalyst lifetime compared to previous H2S tests with pure TiO2 because total H2S elimination was maintained for more than 30 operating hours with SO2 appearing in the outlet as reaction product only after 18 h. Subsequently, the hybrid material was successfully tested in a photoreactor prototype to treat real polluted air in a wastewater treatment plant. For this purpose, a new tubular photocatalytic reactor that may use solar radiation in combination with artificial radiation was designed; the lamp was turned on when solar UV-A irradiance was below 20 W m–2, which was observed to be the minimum value to ensure 100% conversion. The efficient distribution of the opaque photocatalyst inside the tubular reactor was achieved by using especially designed star-shaped structures. These structures were employed for the arrangement of groups of eight TiO2–SiMgOx plates in easy-to-handle channelled units obtaining an adequate flow regime without shading. The prototype continuously removed during one month and under real conditions the H2S contained in a 1 L min–1 air current with a variable inlet concentration in the range of tens of ppmv without release of SO2.The authors would like to acknowledge Comunidad de Madrid (DETOX-H2S S-0505/AMB/0406), Spanish Ministry of Science and Innovation (CTM2008-06876-C02-01/02 and postdoctoral contracts of R.P., S.S. and M.D.H.A), and AECID for financial support and M.L. Rojas-Cervantes for the TG-MS instrument.Peer reviewe

    The role of the surface acidic/basic centers and redox sites on TiO2 in the photocatalytic CO2 reduction

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    The development of sustainable processes for CO reduction to fuels and chemicals is one of the most important challenges to provide clean energy solutions. The use of sunlight as renewable energy source is an interesting alternative to power the electron transfer required for artificial photosynthesis. Even if redox sites are mainly responsible for this process, other reactive acidic/basic centers also contribute to the overall reaction pathway. However, a full understanding of the CO photoreduction mechanism is still a scientific challenge. In fact, the lack of agreement on standardized comparison criteria leads to a wide distribution of reported productions, even using the same catalyst, which hinders a reliable interpretation. An additional difficulty is ascertaining the origin of carbon-containing products and effect of surface carbon residues, as well as the reaction intermediates and products under real dynamic conditions. To determine the elusive reaction mechanism, we report an interconnected strategy combining in-situ spectroscopies, theoretical studies and catalytic experiments. These studies show that CO photoreduction productions are influenced by the presence of carbon deposits (i.e. organic molecules, carbonates and bicarbonates) over the TiO surface. Most importantly, the acid/base character of the surface and the reaction medium play a key role in the selectivity and deactivation pathways. This TiO deactivation is mainly initiated by the formation of carbonates and peroxo- species, while activity can be partially recovered by a mild acid washing treatment. We anticipate that these findings and methodology enlighten the main shadows still covering the CO reduction mechanism, and, most importantly, provide essential clues for the design of emergent materials and reactions for photo(electro)catalytic energy conversion

    Development of an activity disease score in patients with uveitis (UVEDAI)

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    To develop a disease activity index for patients with uveitis (UVEDAI) encompassing the relevant domains of disease activity considered important among experts in this field. The steps for designing UVEDAI were: (a) Defining the construct and establishing the domains through a formal judgment of experts, (b) A two-round Delphi study with a panel of 15 experts to determine the relevant items, (c) Selection of items: A logistic regression model was developed that set ocular inflammatory activity as the dependent variable. The construct "uveitis inflammatory activity" was defined as any intraocular inflammation that included external structures (cornea) in addition to uvea. Seven domains and 15 items were identified: best-corrected visual acuity, inflammation of the anterior chamber (anterior chamber cells, hypopyon, the presence of fibrin, active posterior keratic precipitates and iris nodules), intraocular pressure, inflammation of the vitreous cavity (vitreous haze, snowballs and snowbanks), central macular edema, inflammation of the posterior pole (the presence and number of choroidal/retinal lesions, vascular inflammation and papillitis), and global assessment from both (patient and physician). From all the variables studied in the multivariate model, anterior chamber cell grade, vitreous haze, central macular edema, inflammatory vessel sheathing, papillitis, choroidal/retinal lesions and patient evaluation were included in UVEDAI. UVEDAI is an index designed to assess the global ocular inflammatory activity in patients with uveitis. It might prove worthwhile to motorize the activity of this extraarticular manifestation of some rheumatic diseases

    Retos del PATEC ante la comparativa de otras experiencias de acción tutorial universitaria

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    Tras más de una década de la puesta en marcha del Programa de Acción Tutorial en la Facultad de Económicas siguen persistiendo debilidades que tratan de resolverse año a año. En este sentido, el Programa se ha tratado de mejorar desde la creación de la Red de Tutores del PATEC en el curso 2013-2014. Del trabajo de la Red ha surgido el Manual del tutor, entendido como un recurso que recopila la información básica que va a necesitar el tutor para orientar a su alumnado; la idea de implantar la figura del alumno-tutor en la Facultad para acercar el Programa al conjunto del alumnado; y en el presente curso se ha planteado estudiar la acción tutorial en otras universidades españolas con el objetivo de recopilar buenas prácticas y analizar la posibilidad de implementarlas en la Facultad. Esta comunicación recoge el trabajo realizado por la Red y se estructura de la siguiente manera: en primer lugar, se identifican las prácticas de acción tutorial de diversas universidades españolas; en segundo lugar, se comparan con las actividades realizadas en el marco del PATEC; y, finalmente, se proponen acciones que contribuyan a mejorar el funcionamiento del PATEC

    Resultados preliminares de la influencia de la temperatura de cultivo sobre la proporción de sexos en el rodaballo (Scophthalmus maximus L.)

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    Las larvas de tres familias de rodaballos se cultivaron a temperaturas de 15'C, 18'C y 22'C desde el día dos hasta día 90 de vida y a temperatura ambiente hasta el dia 210. En las familias 1 y 2 las proporciones sexuales, determinadas por el fenotipo, oscilaron en los tres grupos entre el 40%- 60%,y no se observaron diferencias siqníñcaffvas entre los diferentes grupos de temperatura (p>0.05). En la familia 3, el porcentaje de hembras fue mayor que el de machos en los tres grupos de temperatura, y además se observó diferencia significativa (p<0.05) entre el grupo de peces cultivados a temperatura fría con respecto a los cultivados en agua ambiente. En tas familias 1 y 2 el sexo genético coincidió en gran medida con~ sexo fenolípico, siendo la discrepancia menor del 10%. Sin embargo, en la familia 3 se observó que el 36,5% de los machos genéticos eran hembras a 15'C, el 29% a 18ºC y el 18% a 23'C. Los resultados sugieren la interacción temperatura-familia en la determinación sexual del rodaballo, que debe ser confirmada en un mayor número de familias.Larvae from three families of turbot were cultured at 15'C, 18'C and 22'C from 2 to 90 days old, and then at ambient temperature until210 daysold. Regarding families 1 and 2, \he sexual proportions determined by \he phenotype varied between 40%·60%, regardless of \he cunure temperature (p>O.05). Gontrary, in family 3, \he percentage of females was higher than for males in all three cunure temperatures. Furthermore, \here were differences (¡¡<O.05) between families cultured at 15'C and 18'C. For families 1 and 2, sex determined by genotype was similarto \hat detennined by the phenotype, wi\h differences <1 0%. Gontrary, for family 3,\he \he percentage of males determined by \he genotype \hat were phenotipycatt¡ females was 36, 29 and 18% for animals cunured at 15'C, 18'C and 22'C, respectively. Results suggest an interaction temperature-family in \he turbot sex determination which should be checked on a higher numberoffamilies

    Haplotypes of intron 4 of the estrogen receptor alpha gene and hip fractures: a replication study in Caucasians

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    <p>Abstract</p> <p>Background</p> <p>Despite their great impact, few genetic association studies have used hip fractures as an endpoint. However, the association of two polymorphisms on intron 4 of estrogen receptor alpha (<it>ESR1</it>) with hip fractures was recently reported in a Chinese population. The aim of this study was to investigate whether such association is also present in Caucasians.</p> <p>Methods</p> <p>We analyzed those two SNPs and another neighbour SNP located on the exon 4 of <it>ESR1 </it>in 787 patients with hip fractures and 953 controls from Spain.</p> <p>Results</p> <p>The allelic frequencies differed markedly from those reported in Asian populations. Nevertheless, haplotypes including the rs3020314 and rs1884051 loci in intron 4 showed a significant association with hip fractures (omnibus test p = 0.006 in the whole group and 0.00005 in women). In the sex-stratified analysis, the association was significant in females, but not in males. In women, the CA haplotype appeared to have a protective influence, being present in 6.5% of the controls, but only in 3% of patients with fractures (odds ratio 0.39; 95% confidence interval 0.26-0.59; estimated population preventive fraction 3.5%). The inclusion of the rs1801132 SNP of exon 4 further increased the statistical significance of the association (odds ratio 0.17; 95% CI 0.08-0.37; p = 0.00001). Each SNP appeared to contribute independently to the association. No genotype-related differences in gene expression were found in 42 femoral bone samples.</p> <p>Conclusions</p> <p>This study confirms the association of some polymorphisms in the region of exon 4/intron 4 of <it>ESR1 </it>and hip fractures in women. However, there are marked differences in allele frequencies between Asian and Caucasian populations.</p

    Red de tutores del Programa de Acción Tutorial de la Facultad de Económicas (PATEC)

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    El Plan de Acción Tutorial (PAT, PATEC en la Facultad de Ciencias Económicas y Empresariales) se viene desarrollando en la Universidad de Alicante (UA) desde el curso 2005-2006. Tras más de una década de su puesta en marcha en la Facultad de Ciencias Económicas y Empresariales, el PATEC se ha ido consolidando año a año y, aunque son muchas sus fortalezas, existen aún ciertas debilidades que persisten a las que hay que dar respuesta. Para ello, en el curso 2013-2014 surge la Red de Tutores del PATEC como un punto de encuentro en el que reflexionar sobre el funcionamiento del Programa. En el curso 2015-2016 su objetivo es doble. Por un lado, y continuando la labor que comenzó en el curso anterior referida a analizar experiencias de acción tutorial en otras universidades españolas, extraer las buenas prácticas que supongan un nuevo impulso para el PATEC. Por otro, conocer la experiencia de la primera promoción de alumnos-tutores de la Facultad

    Riesgo quirúrgico tras resección pulmonar anatómica en cirugía torácica. Modelo predictivo a partir de una base de datos nacional multicéntrica

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    Introduction: the aim of this study was to develop a surgical risk prediction model in patients undergoing anatomic lung resections from the registry of the Spanish Video-Assisted Thoracic Surgery Group (GEVATS). Methods: data were collected from 3,533 patients undergoing anatomic lung resection for any diagnosis between December 20, 2016 and March 20, 2018. We defined a combined outcome variable: death or Clavien Dindo grade IV complication at 90 days after surgery. Univariate and multivariate analyses were performed by logistic regression. Internal validation of the model was performed using resampling techniques. Results: the incidence of the outcome variable was 4.29% (95% CI 3.6-4.9). The variables remaining in the final logistic model were: age, sex, previous lung cancer resection, dyspnea (mMRC), right pneumonectomy, and ppo DLCO. The performance parameters of the model adjusted by resampling were: C-statistic 0.712 (95% CI 0.648-0.750), Brier score 0.042 and bootstrap shrinkage 0.854. Conclusions: the risk prediction model obtained from the GEVATS database is a simple, valid, and reliable model that is a useful tool for establishing the risk of a patient undergoing anatomic lung resection
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