Eina docent de suport a l'autoavaluació

El present projecte té com a objectiu dissenyar una pàgina web en php que serveixi als alumnes com a suport per a l’autoavaluació. Això es farà donant als professors unes eines d’edició, suficientment intuïtives i fàcils d’utilitzar, per crear preguntes i exàmens que els alumnes podran respondre posteriorment. Aquests exàmens es corregiran automàticament, oferint a l’alumne una quantitat extra d’exercicis a fer. Els usuaris no només se’n beneficiaran amb la possibilitat de practicar amb exercicis addicionals, sinó que serà una bona manera per a autoavaluar-se i saber fins a quin nivell es té assolida l’assignatura abans de fer els exàmens que es tenen en compte per a l’avaluació final. El professor també es podrà fer amb una idea de a quin nivell es troben els alumnes consultant els seus resultats

Modelling environment for the design and optimisation of energy polygeneration systems

The optimal design and operation of an energy supply system is very important for the matching of the energy production and consumption especially in the residential-tertiary sector characterized by an energy demand with a high variability. The main objective of this thesis is to develop an optimisation environment for the preliminary design and analysis of polygeneration plants. The optimisation models are organized in different units represented by blocks that can be connected between each other to create the flowsheet of the polygeneration system. To characterize the energy demand in the residential and tertiary sector a graphic methodology has been developed to select typical energy demand days from a yearly energy demand profile. The environment developed has been applied to two case studies: a small scale polygeneration plant using a liquid desiccant system for air conditioning and a polygeneration plant connected to a district heating and cooling network

The Autonomous Capacity of the Elderly Population in Spain for Shopping and Preparing Meals

A loss of the ability to buy and prepare meals, especially in people aged 65 and over, leads to a deterioration in their optimal level of nutrition. The Index of Autonomy in Food Acquisition (IAFA) was used to identify contributing factors. This is a composite indicator for shopping and meal preparation that can be used to assess the degree of autonomous capacity observed in a spe-cific group. Data from the European Health Survey in Spain (7167 respondents aged 65 and over) show that capacity decreased with age and that women were less affected than men, with very little difference found in levels of autonomous capacity by territory. However, in relation to dif-ferent income levels, after standardizing for age and sex, no evidence was found for differences in the ability to access and prepare meals in groups that were separated by income level. This result shows the importance of standardizing when analysing food acquisition autonomy in groups of people aged 65 years and over

The Price of luck

We find that the vast majority of students taking an advanced undergraduate finance course show a preference for luck in a classroom experiment. In Phase I of the experiment part of the students, group A, were asked to guess a coin toss five times in a row. In Phase II the rest of the students, group B, were given 10 EUR to bet on some of the Group A students taking a second go at guessing a sequence of five coin tosses (Phase III). Group B students' bets were by default allocated to the worse performing student in Phase I. Switching to better performing Group A students was costly. A total of 23 out of 28 students were willing to pay for switching and thus showed a preference for luck

Modificación de los parámetros del polímero en el termofijado del poliéster a diferentes temperaturas

Se ha termofijado un tejido de poliéster a temperaturas nominales entre 160 y 220ºC. De los sustratos correspondientes se han determinado la temperatura efectiva, la cristalinidad, el peso molecular medio y su distribución, el contenido de grupos carboxílicos y de oligómeros superficiales, el grado de blanco y el índice de amarillo. De este modo se han podido evaluar los cambios de cristalinidad y la migración de oligómeros a la periferia de la fibra, así como una posible redistribución de pesos moleculares y un ataque químico-térmico en la operación de termofijado.A polyester cloth was heatset at nominal temperatures between 160 and 220ºC. From the corresponding substrates the effective temperature, the cristallinity, the mean molecular weight and its distribution, the content of carboxylic groups and of superficial oligomers, the degree of whiteness and the yellow index were determined. In this way it was possible to evaluate the changes of cristallinity and the migration of oligomers to the periphery of the fibre, along with a possible redistribution of molecular weights and a chemico-thermal attack in the heat-fixing operation.Nous avons thermofixé un tissu en polyester à des températures nominales allant de 160 à 220 ºC. A partir des substrats correspondants, nous avons déterminé la température effective, la cristallinité, le poids moléculaire moyen et sa distribution, le contenu de groupes carboxyliques et d’oligomères superficiels, le degré de blancheur et le pourcentage de jaune. Nous avons donc pu évaluer les changements de cristallinité et la migration des oligomères à la périphérie de la fibre, ainsi que la redistribution éventuelle des poids moléculaires et l’attaque chimique et thermique pendant la thermofixation

Enzymatic Synthesis of Trimethyl-ϵ-caprolactone : Process Intensification and Demonstration on a 100 L Scale

Optimization and scaling up of the Baeyer-Villiger oxidation of 3,3,5-trimethyl-cyclohexanone to trimethyl-ε-caprolactones (CHLs) were studied to demonstrate this technology on a 100 L pilot plant scale. The reaction was catalyzed by a cyclohexanone monooxygenase from Thermocrispum municipale that utilizes the costly redox cofactor nicotinamide adenine dinucleotide phosphate (reduced form), which was regenerated by a glucose dehydrogenase (GDH). As a first stage, different cyclohexanone monooxygenase formulations were tested: cell-free extract, whole cells, fermentation broth, and sonicated fermentation broth. Using broth resulted in the highest yield (63%) and required the least biocatalyst preparation effort. Two commercial glucose dehydrogenases (GDH-105 and GDH-01) were evaluated, resulting in similar performances. Substrate dosing rates and biocatalyst loadings were optimized. On a 30 mL scale, the best conditions were found when 30 mM h-1 dosing rate, 10% (v/v) cyclohexanone monooxygenase broth, and 0.05% (v/v) of glucose dehydrogenase (GDH-01) liquid enzyme formulation were applied. These same conditions (with oxygen instead of air) were applied on a 1 L scale with 92% conversion, achieving a specific activity of 13.3 U gcell wet weight (cww)-1, a space time yield of 3.4 gCHL L-1 h-1, and a biocatalyst yield of 0.83 gCHL gcww-1. A final 100 L demonstration was performed in a pilot plant facility. After 9 h, the reaction reached 85% conversion, 12.8 U gcww-1, a space time yield of 2.7 g L-1 h-1, and a biocatalyst yield of 0.60 gCHL gcww-1. The extraction of product resulted in 2.58 kg of isolated final product. The overall isolated CHL yield was 76% (distal lactone 47% and proximal lactone 53%)

Ketoisophorone synthesis with an immobilized alcohol dehydrogenase

Altres ajuts: Authors also thank COST Action CM 1303-Systems Biocatalysis for financial support.The monoterpenoid α-isophorone is sourced from the available and renewable plant dry matter, as well as a waste recovery operation from acetone. This compound, can be hydroxylated to 4-hydroxy-isophorone which is the main precursor for the synthesis of ketoisophorone. On its turn, ketoisophorone is a key intermediate for the production of carotenoids and Vitamin E. Here, the enzymatic oxidation of 4-hydroxy-isophorone to ketoisophorone is demonstrated employing an alcohol dehydrogenase (ADHaa) from Artemisia annua and a NADPH oxidase (NOX), as a cofactor regeneration enzyme. After 24 h of reaction and an initial substrate concentration of 50 mM, 95.7 % yield and a space time yield of 6.52 g L⁻¹ day⁻¹ could be obtained. Furthermore, the immobilization of the alcohol dehydrogenase was studied on 17 different supports. An epoxy-functionalized agarose resulted in the highest metrics, 100±0% immobilization yield and 58.2±3.5 % retained activity. Finally, the immobilized ADHaa was successfully implemented in 4 reaction cycles (96 h operation) presenting a biocatalyst yield of 23.4 g product g⁻¹ of enzyme. It represents a 2.5-fold increase compared with the reaction with soluble enzymes

The environmental effects of changing speed limits: a quantile regression approach

Two speed management policies were implemented in the metropolitan area of Barcelona aimed at reducing air pollution concentration levels. In 2008, the maximum speed limit was reduced to 80 km/h and, in 2009, a variable speed system was introduced on some metropolitan motorways. This paper evaluates whether such policies have been successful in promoting cleaner air, not only in terms of average pollutant levels but also during high and low pollution episodes. To do so, we use a quantile regression approach for fixed effect panel data, which allows us analyzing different scenarios (beyond the average levels). We find that the variable speed system improves air quality with regard to the two pollutants considered here, being most effective when nitrogen oxide levels are not too low and when particulate matter concentrations are below extremely high levels. However, reducing the maximum speed limit from 120/100 km/h to 80 km/h has no effect - or even a slightly increasing effect - on the two pollutants, depending on the pollution scenario. Document type: Articl

The Covid-19 impacts on the European Union aquaculture sector

There have been a number of indications of strong negative impacts of Covid-19 and the preventive measures associated with the pandemic for all food sectors. However, there is increasing evidence that the picture is quite nuanced where the Covid related measures are creating challenges for some and opportunities for others. In this paper we investigate the impacts of Covid-19 on the aquaculture sector in the European Union using two approaches; a survey where industry representatives and experts assess the impacts on key economic indicators allowing for positive as well as negative impacts, and recently published aquaculture production data for Denmark and Spain. Our findings show that surveys? results indicate that, on average, the impact of Covid-19 is negative on the income side, increasing cost and therefore negative with respect to profit. However, in every category the average covers both positive and negative answers suggesting that what was a challenge for some was a window of an opportunity for others. The production data for Denmark and Spain also indicate moderate to no impacts of the Covid-19. The strongest impacts appear on the turbot prices, a species where highly dependent on higher end restaurants. The lower price is a clear indication that there was a significant opportunity cost associated with getting access to other supply chains, particularly as the quantity was also moderately down