Generació d'electricitat en plaques fotovoltaiques : seqüència didàctica per a l'estudi de les plaques fotovoltaiques

Treball que correspon a les pràctiques que es fan als tallers REVIR organitzats pel CRECIM de la UAB. La seqüència pretén que l'alumnat de segon a quart d'ESO assoleixi una major comprensió del fenomen de la generació d'electricitat a partir de plaques fotovoltaiques

Unraveling the active microbial populations involved in nitrogen utilization in a vertical subsurface flow constructed wetland treating urban wastewater

The dynamics of the active microbial populations involved in nitrogen transformation in a vertical subsurface flow constructed wetland (VF) treating urban wastewater was assessed. The wetland (1.5 m2) operated under average loads of 130 g COD m- 2 d- 1 and 17 g TN m- 2 d- 1 in Period I, and 80 g COD m- 2 d- 1 and 19 g TN m- 2 d- 1 in Period II. The hydraulic loading rate (HLR) was 375 mm d- 1 and C/N ratio was 2 in both periods. Samples for microbial characterization were collected from the filter medium (top and bottom layers) of the wetland, water influent and effluent at the end of Periods I (Jun–Oct) and II (Nov–Jan). The combination of qPCR and high-throughput sequencing (NGS, MiSeq) assessment at DNA and RNA level of 16S rRNA genes and nitrogen-based functional genes (amoA and nosZ-clade I) revealed that nitrification was associated both with ammonia-oxidizing bacteria (AOB) (Nitrosospira) and ammonia-oxidizing archaea (AOA) (Nitrososphaeraceae), and nitrite-oxidizing bacteria (NOB) such as Nitrobacter. Considering the active abundance (based in amoA transcripts), the AOA population revealed to be more stable than AOB in both periods and depths of the wetland, being less affected by the organic loading rate (OLR). Although denitrifying bacteria (nosZ copies and transcripts) were actively detected in all depths, the denitrification process was low (removal of 2 g TN m- 2 d- 1 for both periods) concomitant with NOx-N accumulation in the effluent. Overall, AOA, AOB and denitrifying bacteria (nosZ) were observed to be more active in bottom than in top layer at lower OLR (Period II). A proper design of OLR and HLR seems to be crucial to control the activity of microbial biofilms in VF wetlands on the basis of oxygen, organic-carbon and NOx-N forms, to improve their capacity for total nitrogen removal.Peer ReviewedPostprint (author's final draft

Valoració dels estudiants de l’assignatura pràcticum del grau en infermeria en les unitats de salut maternal i salut sexual i reproductiva

Estudi vinculat al projecte: ACOPI-UB - Aprenentatge de Competències Professionals en Infermeria. GINDOC-UB/145[cat] Introducció. Estudi sobre la valoració dels estudiants que han cursat l'assignatura Pràcticum i realitzat la formació clínica, en les unitats de salut maternal i salut sexual i reproductiva en els centres assistencials de Barcelona ciutat. Objectiu. Identificar el grau de satisfacció dels estudiants en relació a l'assignatura pràcticum del Grau en Infermeria. Mètode. Disseny. Estudi descriptiu i transversal. Subjectes i emplaçament. N=170 estudiants de pràcticum de l'Escola d'Infermeria de la UB, de quatre cursos acadèmics. Unitats d'hospitalització de ginecologia, obstetrícia, urgències, cures obstètriques intensives de l'HCB i seu Maternitat, i atenció a la salut sexual i reproductiva (ASSIR) d'atenció primària de Barcelona ciutat. Recollida de dades. Qüestionari que recollia entre altres variables: grau d'assoliment dels objectius, grau de satisfacció activitats d'aprenentatge programades i la unitat de pràctiques. Els ítems s’avaluaven mitjançant una escala tipus Lickert (1-10). Anàlisi estadística programa PASW.22. Resultats. Es van obtenir 87 enquestes (51,2%). Principals resultats: grau d'assoliment dels objectius (mitjana) de 8,70 ± 0,94 (6-10), grau de satisfacció dels seminaris (mitjana) 8,05 ± 1,65 (1-10), grau de satisfacció del diari reflexiu (mitjana) 7,43 ± 1,65 (1-10), grau de satisfacció del procés de cures (mitjana) 7,15 ± 1,75 (1-10) i la unitat de pràctiques és adequada per a la consecució dels objectius (mitjana) 8,46 ± 1,33 (5-10). Conclusió. A partir dels resultats plantegem revisar les activitats programades per millorar el procés d'aprenentatge en les pràctiques clíniques.[spa] Introducción. Estudio sobre la valoración de los estudiantes que han cursado la asignatura Prácticum y realizado la formación clínica, en las unidades de salud maternal y salud sexual y reproductiva en los centros asistenciales de Barcelona ciudad. Objetivo. Identificar el grado de satisfacción de los estudiantes en relación a la asignatura Prácticum del Grado en Enfermería. Método. Diseño. Estudio descriptivo y transversal. Sujetos y emplazamiento. N = 170 estudiantes de prácticum de la Escuela de Enfermería de la UB, de cuatro cursos académicos. Unidades de hospitalización de ginecología, obstetricia, urgencias, cuidados obstétricos intensivos del HCB y sede Maternidad, y atención a la salud sexual y reproductiva (ASSIR) de atención primaria de Barcelona ciudad. Recogida de datos. Cuestionario que recogía entre otras variables: grado de consecución de los objetivos, grado de satisfacción de las actividades de aprendizaje programadas y la unidad de prácticas. Los ítems se evaluaban mediante una escala tipo Likert (1-10). Análisis estadístico programa PASW.22. Resultados. Se obtuvieron 87 encuestas (51,2%). Principales resultados: grado de consecución de los objetivos (media) de 8,70 ± 0,94 (6-10), grado de satisfacción de los seminarios (media) 8,05 ± 1,65 (1-10), grado de satisfacción del diario reflexivo (media) 7,43 ± 1,65 (1-10), grado de satisfacción del proceso de cuidados (media) 7,15 ± 1,75 (1-10) y la unidad de prácticas es adecuada para la consecución de los objetivos (media) 8,46 ± 1,33 (5-10). Conclusión. A partir de los resultados planteamos revisar las actividades programadas para mejorar el proceso de aprendizaje en las prácticas clínicas.Programa de Millora i Innovació Docent (PMID). Universitat de Barcelona

Multi-criteria analysis of detoxification alternatives: techno-economic and socio-environmental assessment

The transformation of fermentable sugars provided from lignocellulosic wastes into biofuels or bioproducts is a key point at second-generation biorefineries. Spent sulfite liquor is a xylose-rich hydrolysate constituting the main residue of sulfite mills producing dissolving cellulose. Due to the presence of the inhibitors in the spent liquor, the most promising valorization options require detoxification before sugars bioconversion. In this work, a multi criteria analysis was implemented to select techno-economic and socio-environmental feasible detoxification alternatives that can be adapted to a wide variety of fermenting scenarios. Total inhibitors removal, phenolics removal, acetic acid removal, lignosulfonates removal, total sugar losses, fixed capital invested, manufacturing costs, waste toxicity, social acceptance, and employment were chosen as the most relevant criteria. The maximum allowable concentration of undesirable inhibitors cannot be established with a general character, and thereby decision-making tools result in feasible and efficient solutions. From a technical viewpoint best solution was anionic resins with a score of 0.68; the most economical alternative was the overliming with a score of 0.76; finally, from a socio-environmental perspective, overliming reached the highest score of 0.78. In addition, three spent liquor biorefinery models were proposed. Based on the multicriteria analysis and based on the inhibitor?s concentration affecting fermentation yields and productivity, the best detoxification alternatives were (1) anionic resins for polyhydroxyalkanoate production; (2) activated carbon for ethanol biorefinery; (3) overliming for xylitol biorefinery.The authors gratefully acknowledge the financial support by KBBE-2012-6-311935 BRIGIT research project www.brigit-project.e

Tailoring magnetic and mechanical properties of mesoporous single-phase Ni-Pt films by electrodeposition

Homogeneous mesoporous Ni-rich Ni-Pt thin films with adjustable composition have been synthesised by one-step micelle-assisted electrodeposition. The films exhibit a face-centred cubic solid solution (single phase) and their magnetic and mechanical properties can be tuned by varying the alloy composition. In particular, the Curie temperature (TC) is shown to decrease with the Pt content and thin films with a TC close to room temperature (i.e. Ni58Pt42) and below can be produced. Hysteresis loops show a decrease of saturation magnetisation (Ms) and coercivity (Hc) with decreasing Ni content. A comparison of porous and dense films reveals significantly lower saturation magnetic field strength for porous films. Concerning mechanical properties, mainly two trends can be observed: a decrease of the Young's modulus of the nanoporous films with respect to dense films by 10% in average and a progressive increase of Young's modulus with the Ni content from 4.2 GPa to 5.7 GPa in both types of films. The tunability of properties and facility of synthesis make this alloy a promising material for microelectromechanical systems (MEMS)

Estudi dels hàbits esportius de la població en edat escolar de la ciutat de Barcelona

Sol·licitant de l'informe: Institut Barcelona Esport

Effects of partially saturated conditions on the metabolically active microbiome and on nitrogen removal in vertical subsurface flow constructed wetlands

Nitrogen dynamics and its association to metabolically active microbial populations were assessed in two vertical subsurface vertical flow (VF) wetlands treating urban wastewater. These VF wetlands were operated in parallel with unsaturated (UVF) and partially saturated (SVF) configurations. The SVF wetland exhibited almost 2-fold higher total nitrogen removal rate (5 g TN m−2 d−1) in relation to the UVF wetland (3 g TN m−2 d−1), as well as a low NOx-N accumulation (1 mg L−1 vs. 26 mg L−1 in SVF and UVF wetland effluents, respectively). After 6 months of operation, ammonia oxidizing prokaryotes (AOP) and nitrite oxidizing bacteria (NOB) displayed an important role in both wetlands. Oxygen availability and ammonia limiting conditions promoted shifts on the metabolically active nitrifying community within ‘nitrification aggregates’ of wetland biofilms. Ammonia oxidizing archaea (AOA) and Nitrospira spp. overcame ammonia oxidizing bacteria (AOB) in the oxic layers of both wetlands. Microbial quantitative and diversity assessments revealed a positive correlation between Nitrobacter and AOA, whereas Nitrospira resulted negatively correlated with Nitrobacter and AOB populations. The denitrifying gene expression was enhanced mainly in the bottom layer of the SVF wetland, in concomitance with the depletion of NOx-N from wastewater. Functional gene expression of nitrifying and denitrifying populations combined with the active microbiome diversity brought new insights on the microbial nitrogen-cycling occurring within VF wetland biofilms under different operational conditions.info:eu-repo/semantics/acceptedVersio

On the parameters influencing the deposition of polystyrene colloidal crystals

Colloidal crystals of polystyrene particles of 1.0, 1.4 and 2.8 μm diameter have been prepared by vertical deposition. The influence of parameters such as temperature, particle size and concentration as well as dispersion medium has been studied. The size of domain and the crystalline structure of the particle arrays have been analyzed by optical microscopy. The quality of the crystals has been improved (minimizing cracks) by controlling sedimentation (density matching), evaporation (volatility of the medium) and drying (co-solvents)