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From chalk to chip: the use of artificial intelligence in the classroom
No full textIn 2023, a group of professors from the University of Girona, with arguments in favor of artificial intelligence in the classroom and interested in its possibilities in university teaching, created an informal working group. This book collects part of the results of the group's work, combined with the search of information on a topic that is constantly evolvingL'any 2023 un grup de professores i professors de la Universitat de Girona amb arguments a favor de la intel·ligència artificial a les aules i interessats per les possibilitats d'aquesta en la docència universitària varen crear un grup de treball informal. Aquest llibre recull una part dels resultats del treball del grup, combinats amb la recerca de la informació sobre un tema que evoluciona de forma permanent
Exploring the use of Rh-catalyzed cyclization reactions for the functionalization of fullerenes
No full textENG- Fullerenes are spherical carbon allotropes formed by an even number of carbon atoms organized in twelve pentagons and a variable number of hexagons, being C60 and C70 the two most widely known fullerenes of this family of compounds. Since their discovery, they have aroused great interest due to their characteristics and properties, which make them attractive compounds for various applications in the fields of biomedicine and photovoltaic energy. However, one of the main disadvantages of their use is that they must be previously functionalized to make them more manipulable. Although significant progress has been achieved in the field of fullerene functionalization, there is still much to be discovered. Currently, the emphasis is on improving the selectivity of processes and efficiently synthesizing new derivatives using innovative methods, compounds which may be potentially interesting for applications. The use of cyclizations catalyzed or promoted by transition metals has become one of the efficient alternatives to synthesize fullerene derivatives fused with carbo- and heterocyclic rings of different sizes and varied functionality.
Our research group has considerable experience in the development of transition metal-catalyzed cyclizations, specifically, rhodium-catalyzed [2+2+2] cycloadditions involving various unsaturations. Recently, this reaction has been applied to the functionalization of fullerenes, where a rhodium-catalyzed [2+2+2] cycloaddition reaction between 1,6-diynes and C60 has allowed the synthesis of new open-cage derivatives of C60. Some of the derivatives prepared have proven to be good electron transport materials in perovskite solar cells.
The main objective of this doctoral thesis is to focus on the development of new methodologies for the functionalization of fullerenes through cyclization processes catalyzed by rhodium involving different unsaturated substrates. The work begins by undertaking a revision of the cyclization processes catalyzed or promoted by transition metals used for the functionalization of fullerenes that have been reported in the literature, offering an overview of the main topic of the doctoral thesis. We then go on to describe the synthesis of open-cage derivatives of C70 from the use of 1,6-diynes, applying the methodology previously reported by our group, with special emphasis on the regioselectivity of the process. This is followed by an extensive study of cyclization reactions of C60 and/or C70 catalyzed by different rhodium-based catalytic systems involving unsaturated substrates such as 1,5-bisallenes, 1,6-enynes and 1,6-allenynes. In these studies, the catalytic process is optimized, the scope of the reaction is carried out by varying the unsaturated substrates and the mechanism of the new process is investigated through experiments and computational studies based on DFT calculations. The final result is to allow the efficient preparation of a wide range of new fullerene derivatives with 6,5-, 6,6- and 6,7-membered ring fusionsCAT- Els ful·lerens són al·lòtrops esfèrics del carboni formats per un nombre parell d’àtoms de carboni organitzats en dotze pentàgons i un nombre variable d’hexàgons, sent el C60 i el C70 els dos ful·lerens més representatius d’aquesta família de compostos. Des del seu descobriment, han despertat un gran interès degut a les seves característiques i propietats, convertint-los en compostos atractius per diverses aplicacions, com ara en l’àmbit de la biomedicina o de l’energia fotovoltaica. No obstant això, un dels principals desavantatges pel seu ús és el fet que han d’estar prèviament funcionalitzats per tal de que siguin més manipulables. Tot i que s’han realitzat progressos en el camp de la funcionalització de ful·lerens, encara queda molt per descobrir. Actualment, les investigacions es centren en millorar la selectivitat dels processos i sintetitzar de manera eficient nous derivats a través de mètodes innovadors, compostos que poden ser potencialment interessants per a certes aplicacions. L’ús de les ciclacions catalitzades o promogudes per metalls de transició han esdevingut una de les alternatives eficients per sintetitzar derivats de ful·lerè fusionats amb anells carbo- i heterocíclics de diferents mides i variada funcionalitat.
El nostre grup de recerca presenta una sòlida experiència en el desenvolupament de ciclacions catalitzades per metalls de transició, concretament, en les cicloaddicions [2+2+2] catalitzades per rodi involucrant diverses insaturacions. Recentment, s’ha aplicat aquesta reacció a la funcionalització de ful·lerens, on mitjançant una reacció de cicloaddició [2+2+2] catalitzada per rodi entre 1,6-diïns i C60 ha permès la síntesi de nous derivats open-cage de C60. Alguns dels derivats preparats han demostrat ser bons materials transportadors d’electrons en cel·les solars de perovskita.
L’objectiu principal d’aquesta tesi doctoral es centra en el desenvolupament de noves metodologies per a la funcionalització de ful·lerens mitjançant processos de ciclació catalitzats per rodi involucrant diferents substrats insaturats. S’inicia el treball amb un recull dels processos de ciclació catalitzats o promoguts per metalls de transició emprats per a la funcionalització de ful·lerens reportats a la bibliografia, oferint una visió del tema principal de la tesi doctoral. Seguidament, es descriu la síntesi de derivats open-cage de C70 a partir de l’ús de 1,6-diïns aplicant la metodologia reportada prèviament pel nostre grup, fent especial èmfasi a la regioselectivitat del procés. Tot seguit, es duu a terme un ampli estudi de reaccions de ciclació catalitzades per diferents sistemes catalítics basats en rodi involucrant C60 i/o C70 i substrats insaturats tals com 1,5-bisal.lens, 1,6-enins i 1,6-allenins. En aquests estudis s’optimitzen el procés catalític, es dur a terme l’abast de la reacció variant els substrats insaturats i s’investiga el mecanisme del nou procés mitjançant experiments i estudis computacionals basats en càlculs DFT. Aquests estudis permeten la preparació eficient d’un variat ventall de nous derivats de ful·lerè amb fusions d’anells de 6,5-, 6,6- i 6,7-membresI would like to thank the Spanish Ministry of Economy and Competitivity (Projects CTQ2017-85341-
P and PID2020-113711GB-I00, and FPI predoctoral grant PRE2018-085101) and the Generalitat de Catalunya
(Projects 2017SGR39 and 2021SGR623) for their financial supportPrograma de Doctorat en Químic
Estándar de prueba en controversias por omisión tributaria: Una mirada a la legislación y jurisprudencia ecuatoriana
No full textIn Ecuador, no tax litigation is governed by a standard of proof. This article argues that, for a hypothesis of omission to be confirmed, the two conditions required by Ferrer standard 3 must be met, i.e.: (i) the hypothesis must be able to explain the available data and predict new ones, with the evidence supporting those predictions; and, (ii) the alternative hypothesis must be rebutted, if it is plausible and compatible with the absence of taxpayer liability, as long as it is supported by evidence that provides some degree of confirmation. If both conditions are not met, the absence of liability of the taxpayer shall prevailEn Ecuador, ningún litigio tributario se rige por un estándar de prueba. El planteamiento de este artículo es que, para que una hipótesis de omisión sea confirmada, deberán cumplirse las dos condiciones que exige el estándar 3 sugerido por Ferrer, es decir: (i) la hipótesis debe ser capaz de explicar los datos disponibles y predecir nuevos, con las pruebas que soporten esas predicciones; y, (ii) se debe refutar la hipótesis alternativa, si es plausible y compatible con la ausencia de respon-sabilidad del contribuyente, siempre que esté respaldada por pruebas que aporten algún grado de confirmación. De no superarse ambas condiciones, deberá prevalecer la ausencia de responsabili-dad del sujeto tributario1
Paisaje, bien común y servicios ecosistémicos culturales. Nuevos parámetros de planificación territorial en la interfase de tierras secas (Mendoza - Argentina)
No full textENG- Dryland landscapes around the world face significant challenges due to their inherent fragility and the increasing pressure they face from multiple dimensions. Research suggests that developing territorial management approaches that consider both the tangible and intangible aspects of the environment could be beneficial in addressing these complexities. This doctoral thesis explores the integration of the contemporary notion of landscape, cultural ecosystem services, and the concept of landscape as a common good, with the aim of proposing new parameters for territorial planning that respond to the particularities of these territories. The study focuses on the piedmont of the Metropolitan Area of Mendoza, Argentina, a region representative of drylands, often underestimated, that also acts as an interface between the irrigated urban oasis and the non-irrigated drylands, which gives it particular interest. This uniqueness provides a valuable context to investigate how these new parameters can be applied in an environment marked by the tension between landscape appreciation and urban development demands.
The research begins with an exploratory review of the historical and cultural evolution of the landscape concept, with special emphasis on how intangible values—such as cultural, historical, aesthetic, spiritual elements, among many others—have been fundamental in shaping the contemporary landscape. This approach is framed in the understanding of the landscape not only as a physical space but as a dynamic entity and a social construct, whose management is essential for people's well-being. The European Landscape Convention is presented as a key reference, offering a flexible framework that promotes the inclusion of these intangible values in territorial planning.
The study focuses on the piedmont of the Metropolitan Area of Mendoza, an interface between the urban oasis and the drylands. Through a mixed-methods approach combining qualitative and quantitative approaches, the spatialization of the landscape’s intangible values is carried out using tools such as participatory mapping and citizen science. These methods allow local actors to identify and assess the landscape elements (both tangible and intangible) that they consider essential for their quality of life and well-being, facilitating their integration into territorial planningCAT- Els paisatges de les terres seques arreu del món es troben davant de desafiaments significatius degut a la seva fragilitat inherent i a la creixent pressió que afronten des de múltiples dimensions. La recerca suggereix que podria ser beneficiós desenvolupar enfocaments de gestió territorial que considerin tant els aspectes tangibles com els intangibles de l’entorn per abordar aquestes complexitats. En aquesta tesi doctoral, s'explora la integració de la noció contemporània de paisatge, els serveis ecosistèmics culturals i el concepte de paisatge com a bé comú, amb l’objectiu de proposar nous paràmetres per a la planificació territorial que responguin a les particularitats d’aquests territoris. L’estudi se centra en el Piedemonte de l’Àrea Metropolitana de Mendoza, Argentina, una regió representativa de les terres seques, sovint subestimades, que també actua com a interfície entre l’oasi urbà (regat) i el secà (no regat), cosa que li confereix un interès particular. Aquesta singularitat ofereix un context valuós per investigar com aquests nous paràmetres poden aplicar-se en un entorn marcat per la tensió entre la valoració del paisatge i les demandes de desenvolupament urbà.
La recerca parteix d’una revisió exploratòria de l’evolució històrica i cultural del concepte de paisatge, amb especial èmfasi en com els valors intangibles —com ara els elements culturals, històrics, estètics, espirituals, entre molts altres— han estat fonamentals en la configuració del paisatge contemporani. Aquest enfocament s'emmarca en la comprensió del paisatge no només com un espai físic, sinó com un ésser dinàmic i una construcció social, la gestió de la qual és essencial per al benestar de les persones. El Conveni Europeu del Paisatge es presenta com un referent clau, en oferir un marc flexible que promou la inclusió d’aquests valors intangibles en la planificació territorial.
L’estudi se centra en el Piedemonte de l’Àrea Metropolitana de Mendoza, una interfície entre l’oasi urbà i les terres seques. A través d’una metodologia mixta que combina enfocaments qualitatius i quantitatius, es duu a terme l’espacialització dels valors intangibles del paisatge, utilitzant eines com el mapatge participatiu i la ciència ciutadana. Aquests mètodes permeten als actors locals identificar i valorar els elements (tangibles i intangibles) del paisatge que consideren fonamentals per a la seva qualitat de vida i benestar, facilitant la seva integració en la planificació territorialPrograma de Doctorat en Medi Ambien
Relationship Between Ethical Climate and Burnout: A New Approach Through Work Autonomy
No full textBurnout is a factor that affects organizational performance. Researchers have not determined whether an ethical climate and adequate work autonomy provide sufficient emotional stability to dampen burnout or, conversely, increase it. In addition, the abundant literature analyzing the relationship between work autonomy and burnout does not sufficiently establish whether it acts as a stress-reducing resource or a stress-increasing demand. It is also unknown to what extent work autonomy contributes to explaining the relationship between ethical climate and burnout. Therefore, the main aim of this study is to examine the relationship between an ethical climate based on principles and norms and burnout using the moderating effect of work autonomy. We approached this question using a multivariate moderation analysis. The sample consists of 448 employees in the Colombian electric sector. The results show that an ethical climate of principles and work autonomy are positively related to burnout, measured by the dimensions of emotional exhaustion and depersonalization. However, the relationship between an ethical climate of principles and burnout shifts from positive to negative when a rule-demanding work environment is associated with a high perception of work autonomy. In conclusion, when employees have considerable control over their usual tasks, they develop a pattern of behavior that incorporates both the organization’s internal standards and the principles that shape individual morality. In this case, employees are able to balance the workload with the high psychological demands of an ethical climate of principles, without it being a disturbance to their emotional well-being. The results of this research are particularly relevant because they show for the first time that an ethical climate of principles can have opposite effects on employee burnout, both positive and negative, depending on the degree of work autonomy. This opens the door to new strategies for organizations to prevent certain psychosocial occupational risks, such as burnout, which often have a serious impact on employees’ mental health. Moreover, the model of moderation proposed in this article can be replicated in other Latin American countries with similar characteristics to those of Colombia or even transferred to rich countrie
Quality characteristics of pork bellies with different fat content and their non-destructive prediction by imaging spectroscopy
No full textENG- Pork is one of the most popular meats worldwide and, in some countries, belly is considered a very important cut; however, it is one of the fattiest cuts. In order to satisfy consumer preferences for leaner products, producers have carried out intensive selection to reduce the fat content. This reduction has led to significant changes in the quality characteristics of pork belly, which are important for both producers and consumers. One of the objectives of the thesis was to investigate how quality characteristics change among a wide variety of pork bellies with different fat contents, both as whole pieces and sliced. In addition, pork producers are increasingly looking for more effective and non-destructive methods to determine the quality characteristics of pork belly to optimise production and marketing decisions. Non-destructive methods offer advantages such as speed, efficiency, and safety, allowing continuous quality assessment while ensuring product integrity and accuracy of results. Among these methods, those using different areas of the electromagnetic spectrum have gained attention. This thesis focuses on spectral imaging, which combines imaging and spectroscopy technologies to simultaneously obtain spatial and spectral information about the product. This system makes possible to characterise and identify complex heterogeneous matrices based on the unique spectrum captured for each pixel in the acquired images. Therefore, another objective of the thesis was to test spectral imaging technology for non-destructively predicting the quality characteristics of whole and sliced pork bellyCAT- La carn de porc és una de les més populars a nivell mundial i, en alguns països, la ventresca es considera una peça molt important; tanmateix, és una de les peces més grasses. Per tal de satisfer les preferències dels consumidors per als productes més magres, els productors han dut a terme una selecció intensiva per reduir el contingut de greix. Aquesta reducció ha comportat canvis significatius en les característiques de qualitat de la ventresca de porc, que són importants tant per als productors com per als consumidors. Un dels objectius de la tesi va ser investigar com es modifiquen les característiques de qualitat entre una gran varietat de ventresques de porc amb diferents continguts de greix, tant en les peces senceres com en les llesques. A més, els productors de porc busquen cada vegada més mètodes més efectius i no destructius per a determinar les característiques de qualitat de la ventresca de porc amb la finalitat d’optimitzar la presa de decisions a nivell de producció i comercialització. Els mètodes no destructius ofereixen avantatges com la rapidesa, l'eficiència i la seguretat, permetent una avaluació de la qualitat de manera contínua i, alhora, garantint la integritat del producte i la precisió dels resultats. Entre aquests mètodes, destaquen els que utilitzen diferents zones de l'espectre electromagnètic. Aquesta tesi es centra en la imatge espectral, que combina tecnologies d'imatge i espectroscòpia per obtenir simultàniament informació espacial i espectral sobre el producte. Aquest sistema permet caracteritzar i identificar matrius heterogènies complexes a partir de l'espectre únic capturat per a cada un dels píxels de les imatges adquirides. Per tant, un altre objectiu de la tesi va ser avaluar la tecnologia d'imatge espectral per predir de manera no destructiva les característiques de qualitat de la peça i de les llesques de la ventresca de porcPrograma de Doctorat en Tecnologi
The Spiral of violence experienced by immigrant domestic workers: A qualitative approach
No full textMany immigrant women engaged in domestic work encounter precarious employment conditions characterized by uncertain contracts, often experiencing marginalization based on their racial identities. Through qualitative methods, including 23 in-depth interviews and interpretive analysis, this study aims to explore the structural and circumstantial violence embedded within the narratives of migrant women involved in caregiving and domestic work. These women report a spiral of structural violence influenced by classism, racism, and sexism perpetuated through the use of fear, abuse, and economic coercion. Such violence leads to systemic neglect, verbal and physical abuse, and continual humiliation, resulting in isolation. Immediate action is necessary to reform labor regulations and reshape care services, in order to address deeply ingrained inequalities and safeguard vulnerable women through administrative and labor reform
Agroecologia i sobirania alimentària a Catalunya ; alternatives al sistema alimentari globalitzat : un nou concepte agroecològic d’hort urbà
No full textThe study analyzes the impacts of the globalized food system at a global level, conducting a more
detailed examination of the situation in Catalonia and exploring viable alternatives to ensure a
more sustainable and resilient model. The negative effects of the globalized model have been
studied, including greenhouse gas emissions, biodiversity loss, and soil erosion, as well as the
growing dependence on food imports, which creates significant vulnerability to global crises. In
contrast, realistic alternatives have been sought to reduce the current impact on the planet.
Agroecology emerges as a viable and necessary alternative to mitigate these effects and ensure
a fairer and more sustainable food system. This model promotes crop diversification, reduces
dependence on chemical inputs, and strengthens short food supply chains, supporting local
farming and reducing the ecological footprint. Additionally, concrete initiatives have been
analyzed that contribute to strengthening food sovereignty in Catalonia as well as in other
countries.
This study also examines the fundamental role of urban gardens, not only as food production
spaces but also as tools to promote sustainability, social cohesion, and resilience to climate
change. Furthermore, an innovative combination with mushroom cultivation is proposed, which
could enhance the efficiency of these spaces and diversify food production in urban environments.
The conclusions suggest that the transition to an agroecological model is key to achieving real
food sovereignty and long-term sustainability. However, to accomplish this, public policies that
support small-scale producers, better land-use planning, and a firm commitment to
environmentally respectful production systems are essential111
Citacions i referències bibliogràfiques en estil APA 7a edició
No full textCompilat i adaptat per: Isabel María Rojas Herrera. Coordinació: Isabel Planas Campistol i Disseny portada: BIBEC - Edicions UdGGuia per citar correctament les fonts utilitzades i/o consultades en un treball, la tesi, etc. seguint l'estil de citació APA. Per a l'elaboració d'aquesta guia s'ha seguit la setena edició del “Publication manual of the American Phsychological Association: the official guide of the APA style”