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PLA/PMMA Reactive Blending in the Presence of MgO as an Exchange Reaction Catalyst
No full textTo address the limitations of poly (lactic acid) (PLA), it was blended with poly (methyl methacrylate) (PMMA) as a toughening component, using MgO nanoparticles (NPs, 0.075–0.15 wt%) as a catalyst. SEM pictures confirmed the good miscibility of the blends. Mechanical tests showed a slight decrease in elastic modulus and tensile strength for the PLA/PMMA125 sample containing 0.125% MgO. Yet, elongation at break rose by over 60% and impact strength increased by over 400% compared to pure PLA. Also, MgO facilitated the shifting of the glass transition temperature (Tg) of both polymers in DSC curves. Additionally, the absence of cold crystallization in PLA, coupled with reductions in its melting temperature (Tm) and crystallinity, were identified as critical factors contributing to improved miscibility within the reactive blend. Melt flow index (MFI) evaluation indicated a decrease in viscosity, while water contact angle measurements revealed an increase in polar groups on the surfaces of the MgO-containing samples. X-ray diffraction (XRD) and transmission electron microscopy (TEM) analyses confirmed the effective distribution and dispersion of NPs throughout the blend, along with a significant decrease in crystallinity. Moreover, DFT calculations were performed to better understand the role of MgO in the reaction. The findings offered key insights into the reaction mechanism, confirming that MgO plays a crucial role in facilitating the transesterification between PLA and PMMA. These findings underscore the enhanced performance of exchange reactions between the active groups of both polymers in the presence of MgO, leading to the formation of PLA-PMMA copolymers with superior miscibility and mechanical properties. Finally, a cell culture assay confirmed the blend’s non-toxicity, showing its versatile potentialThis research was funded by the Spanish Ministerio de Ciencia e Innovación for project PID2021-127423NB-I00 and the Generalitat de Catalunya for project 2021SGR623. Financial support from the project 3A-Italy, MICS–PNRR MUR-M4C2-I 1.3 (PE00000004) is gratefully acknowledge
Revolució verda en la restauració: un meta-anàlisis de la sostenibilitat
No full textPresentació de Mireia Pascual Olivé i José Antonio Donaire sobre un estudi consistent en una meta-anàlisi de la sostenibilitat en l'àmbit del turisme, la gastronomia i la restauració111
Which ideas do we get from war museums? A computational text analysis of the museums of the Battle of the Ebro (Spanish Civil War)
No full textWar museums convey traumatic experiences through complex and contested narratives that shape visitors' perceptions. The Ebro battlefield exemplifies these complexities, with multiple institutions preserving its heritage while presenting differing interpretations. This article employs a Digital Humanities approach to analyse the messages conveyed by these museums. The team digitised exhibition panel texts using OCR technology and applied various textual analysis and data visualisation methods, including word frequency counts and topic modelling. The integration of topic modelling in museum discourse analysis enables the quantification of trends and the identification of overlooked narratives. Results reveal a strong emphasis on the conflict's international dimension and a tendency towards politically equidistant narratives. The analysis also highlights the under-representation of certain groups, particularly civilians, and identifies tensions between museum portrayals of looting and heritage lawsTGC received the support of a fellowship from “la Caixa” Foundation (ID 100010434). The fellowship code is LCF/BQ/DR21/11880004. XRC is funded by the Ramón y Cajal programme RYC2018-024050-I (Fondo Social Europeo – Agencia Estatal de Investigación). This research is also part of MAELSTROM PID2023-147060NB-I00 (Ministerio de Ciencia, Innovación y Universidades)Open Access funding provided thanks to the CRUE-CSIC agreement with Elsevie
Novel 8-Hydroxyquinoline-Derived V(IV)O, Ni(II), and Fe(III) Complexes: Synthesis, Characterization, and In Vitro Cytotoxicity Against Tumor Cells
No full textWe report the synthesis and characterization of five novel metal complexes. Three of them are vanadium complexes with the general formula [VO(Ln)2], where Ln are Schiff bases derived from the condensation of 2-carbaldehyde-8-hydroxyquinoline with either 4-(2-aminoethyl)morpholine (L1), 3-morpholinopropylamine (L2) or 1-(2-aminoethyl)piperidine (L3). The two other metal complexes are [Ni(L1)2] and [Fe(L1)2]Cl. They were characterized by analytical, spectroscopic (Fourier transform infrared, UV-visible absorption), and mass spectrometric techniques as well as by single-crystal X-ray diffraction (for all [VO(Ln)2] complexes and [Ni(L1)2]). While, in the crystal structure, the V(IV)O complexes show distorted square-pyramidal geometry with the ligands bound as bidentate through quinolate NO donors, the Ni(II) complex shows octahedral geometry with two ligand molecules coordinated through NNO donors. Stability studies in aqueous media revealed that the vanadium complexes are not stable, undergoing oxidation to VO2(L), which was corroborated by 51V NMR and MS. This behavior is also observed in organic media, though at a significantly slower rate. The Ni complex exhibited small spectral changes over time in aqueous media. Nonetheless, all compounds show enhanced stability in the presence of bovine serum albumin (BSA). Fluorescence studies carried out for the Ni(II) and Fe(III) complexes indicate reversible binding to albumin. The cytotoxicity of the L1 metal complexes was assessed on melanoma (B16F10 and A375) and colon cancer (CT-26 and HCT-116) cell lines, with 5-fluorouracil (5-FU) as a reference drug. The V- and Ni complexes showed the lowest IC50 values (<10 μM) in either A375 or HCT-116 cells after 48 h of incubation, while the Fe(III) complex presented minimal antiproliferative effects. The complexes were generally more cytotoxic to human than murine cancer cells. Synergistic in vitro studies with 5-FU revealed antagonism in most cases, except in A375 cells, where an additive effect was observed for the combination with the V-complex. Overall, these compounds show promising potential for cancer treatment, mostly for melanomaThe authors acknowledge Fundação para a Ciência e a Tecnologia (FCT) for financial support under project references UIDB/00645/2020, UIDP/00645/2020, UIDB/04138/2020, UIDP/04138/2020, UIDB/00100/2020 (https://doi.org/10.54499/UIDB/00100/2020), accessed on 29 April 2025, UIDP/00100/2020 (https://doi.org/10.54499/UIDP/00100/2020), accessed on 29 April 2025, LA/P/0056/2020 (https://doi.org/10.54499/LA/P/0056/2020), accessed on 29 April 2025, PTDC/MED-QUI/31721/2017, and PTDC/QUI-QIN/0586/2020, as well as for the PhD fellowships SFRH/BD/148044/2019 and UI/BD/153626/2022. The Portuguese NMR and mass spectrometry IST-UL are acknowledged for access to the equipment. I. R. acknowledges AGAUR (Generalitat de Catalunya, projects 2021-SGR-00442) and MICINN (PID2022-136892NB-I00
Equipamientos socioculturales y sistemas arquitectónicos resilientes: la Cable Factory y Can Batlló = Sociocultural Facilities and Resilient Architectural Systems: The Cable Factory and Can Batlló
No full textResilience in the field of spatial planning contributes to the sustainable development of socio-spatial systems and deals with the unpredictable effects of climate change in urban areas. This article discusses resilient architecture by comparing two case studies: the former industrial complexes transformed into sociocultural facilities of the Cable Factory in Helsinki and Can Batlló in Barcelona. Through a grounded theory methodology, this research combines three inductive methods to collect data: semi-structured interviews, observational research, and secondary research. The aim of this work is to define properties and characteristics that promote the creation of a conceptual framework in resilient architecture from an evolutionary resilience approach and, thus, contribute to the projection of resilient cities. Thanks to the planning of spatial indeterminacy, the resilient properties of persistence, adaptation and transformation are identified in the architectural systems of both cases. The results show 16 resilient characteristics that are integrated in the spatial, social and temporal dimensions. Two categories of indeterminate space are also distinguished: raw space at the Cable Factory and freespace at Can Batlló. It is concluded that indeterminate spaces offer freedom of appropriation and confront obsolescence and change of use through evolvability and flexibilityLa resiliencia en el ámbito del planeamiento espacial contribuye al desarrollo sostenible de los sistemas socioespaciales y lidia con los efectos impredecibles del cambio climático en las áreas urbanas. Este artículo debate sobre arquitectura resiliente mediante la comparación de dos casos de estudio: los antiguos complejos industriales transformados en equipamientos socioculturales de la Cable Factory en Helsinki y de Can Batlló en Barcelona. Mediante una metodología de teoría fundamentada, esta investigación combina tres métodos inductivos para recopilar los datos de estudio: entrevistas semiestructuradas, investigación observacional e investigación secundaria. El objetivo de este trabajo consiste en definir unas propiedades y características, que propicien la construcción de un marco teórico en la arquitectura resiliente desde un enfoque de resiliencia evolutiva y, con ello, contribuir a la proyección de ciudades resilientes. Gracias a la planificación de la indeterminación espacial, se identifican las propiedades resilientes de persistencia, adaptación y transformación en los sistemas arquitectónicos de ambos casos. Los resultados muestran 16 características resilientes que se integran en las dimensiones espacial, social y temporal. Asimismo, se distinguen dos categorías de espacio indeterminado, esto es, el espacio en bruto en la Cable Factory y el espacio-libre en Can Batlló. Se concluye que los espacios indeterminados ofrecen libertad de apropiación y afrontan la obsolescencia y el cambio de uso mediante la evolucionabilidad y la flexibilidadLa resiliència en l’àmbit de la planificació espacial contribueix al desenvolupament sostenible dels sistemes socioespacials i afronta els efectes imprevisibles del canvi climàtic en les àrees urbanes. Aquest article analitza l’arquitectura resilient mitjançant la comparació de dos casos d’estudi: els antics complexos industrials transformats en equipaments socioculturals de la Cable Factory a Hèlsinki i de Can Batlló a Barcelona. Mitjançant una metodologia de teoria fonamentada, aquesta investigació combina tres mètodes inductius per a la recopilació de dades: entrevistes semiestructurades, recerca observacional i recerca secundària. L’objectiu del treball és definir unes propietats i característiques que facilitin la construcció d’un marc teòric en arquitectura resilient des d’un enfocament de resiliència evolutiva i, així, contribuir a la projecció de ciutats resilients. Gràcies a la planificació de la indeterminació espacial, s’identifiquen les propietats resilients de persistència, adaptació i transformació en els sistemes arquitectònics d’ambdós casos. Els resultats mostren 16 característiques resilients que s’integren en les dimensions espacial, social i temporal. Així mateix, es distingeixen dues categories d’espai indeterminat: l’espai en brut a la Cable Factory i l’espai-lliure a Can Batlló. Es conclou que els espais indeterminats ofereixen llibertat d’apropiació i permeten afrontar l’obsolescència i el canvi d’ús mitjançant la possibilitat d’evolució i la flexibilitat1
Asymmetric oxidative dearomatization of arenes with biologically inspired oxidation catalysts
No full textENG- This thesis investigates the development and application of bioinspired iron and manganese complexes as catalysts for the dearomative oxidation of non-activated arenes, focusing on epoxidation and syn-dihydroxylation reactions. These transformations are particularly difficult because of the inherent stability of aromatic systems. This steadiness likely explains the limited number of known examples. The comparison and contrast with the reactivity of alkenes is quite illustrative since these readily undergo a variety of oxidation reactions with a number of reactants.
While being challenging, arene dearomatization reactions are very appealing because they transform the flat structure of the arene in functionalized and stereochemically rich 3D cyclohexyl moieties. These structures are of immediate interest as building blocks for medicinal chemistry and synthesis of natural products.
The targeted reactions in this thesis will mirror the extraordinary reactivity of certain iron dependent enzymes. In particular, the known arene epoxidation activity displayed by heme P450 enzymes and the arene syn-dihydroxylating activity of several Rieske oxygenases. The reactivity exhibited by these enzymes strongly support the hypothesis that high valent metal oxo compounds have the capability to overcome the poor reactive character of arenes under mild conditions. Therefore, we reasoned that biomimetic catalysts based in small molecule coordination complexes that can generate high valent metal-oxo species may reproduce this activity and become valuable catalysts. With these considerations in mind small molecule iron and manganese catalysts that can sustain high oxidation states have been explored as dearomative oxidation catalysts. By performing these transformations in both non-enantioselective and enantioselective manners, we aim to expand the synthetic toolkit available for the development of complex molecules starting from simple aromatic precursors. In conclusion, this work substantially contributes to the field of arene oxidation, introducing new catalytic systems capable of mimicking enzymatic processes and expands the possibilities for the obtention of complex molecules starting just from simple aromatic precursorsCAT- Aquesta tesi investiga el desenvolupament i l'aplicació de complexos de ferro i manganès bioinspirats com a catalitzadors per a l'oxidació dearomativa d'arens no activats, centrant-se en les reaccions d'epoxidació i sin-dihidroxilació. Aquestes transformacions són particularment difícils a causa de l'estabilitat inherent dels sistemes aromàtics. Aquesta estabilitat probablement explica els exemples limitats que es coneixen. La comparació i el contrast amb la reactivitat dels alquens és força il·lustrativa, ja que aquests últims experimenten fàcilment una varietat de reaccions d'oxidació amb diversos reactius.
Malgrat ser complexes, les reaccions de dearomatització d'arenes són molt atractives perquè transformen l'estructura plana de l'arè en ciclohexocicles tridimensionals, funcionalitzats i amb molta riquesa estereoquímica. Aquestes estructures són d'interès immediat com a blocs de construcció per a la química medicinal i la síntesi de productes naturals.
Les reaccions estudiades en aquesta tesi reflectiran l'extraordinària reactivitat de certs enzims dependents de ferro. En particular, l'activitat d'epoxidació d'arens que mostren els enzims hemo P450 i l'activitat de sin-dihidroxilació d'arens de diverses oxigenases de Rieske. La reactivitat exhibida per aquests enzims dona suport fermament a la hipòtesi que els compostos metall-oxo en estats d'oxidació elevats tenen la capacitat de superar el caràcter poc reactiu dels arens en condicions suaus. Per tant, vam raonar que els catalitzadors biomimètics basats en complexos de coordinació que poden generar espècies metall-oxo d’alta valència podrien reproduir aquesta activitat i esdevenir catalitzadors valuosos. Amb aquestes consideracions en ment, s'han explorat catalitzadors de ferro i manganès que poden mantenir alts estats d'oxidació com a catalitzadors per a l'oxidació dearomativa. A través d'aquestes transformacions, tant de manera no enantioselectiva com enantioselectiva, es pretén ampliar el conjunt d'eines sintètiques disponibles per al desenvolupament de molècules complexes a partir de precursors aromàtics simples. En conclusió, aquest treball contribueix substancialment al camp de l'oxidació d'arens, introduint nous sistemes catalítics capaços d'imitar processos enzimàtics i ampliant les possibilitats per a l'obtenció de molècules complexes a partir de precursors aromàtics simplesPrograma de Doctorat en Químic
Microcredenciales en las Universidades españolas
No full textPresentación de Margalida Furió, secretaria de la Junta Directiva y de la Red Universitaria de Estudios de Posgrado y Educación Permanente, sobre la formación permanente en forma de microcredenciales o micromódulos de las universidades españolas, que certifican resultados de aprendizaje. Hace referencia al "Plan MICROCREDS" presentado en Málaga en junio de 2023, a la documentación elaborada por RUEPEP-CRUE, y muestra diferentes páginas web de diferentes universidades españolas con las microcredenciales que ofrecenPresentació de Margalida Furió, secretaria de la Junta Directiva i de la Red Universitaria de Estudios de Posgrado y Educación Permanente, sobre la formació permanent en forma de microcredencials o micromòduls de les universitats espanyoles , que certifiquen resultats d'aprenentatge. Fa referència al "Plan MICROCREDS" presentat a Màlaga el juny del 2023, a la documentació elaborada per RUEPEP-CRUE, i mostra diferents pàgines web de diferents universitats espanyoles amb les microcredencials que oferten
L' Acompanyament al centre de les polítiques locals de joventut
No full textEs proposa una nova aproximació a les polítiques locals de joventut a partir del coneixement generat al voltant del desenvolupament òptim i els seus factors contextuals, tenint en compte la dimensió de drets, empoderament i comunitat. Aquesta aproximació ha de substituir el model actual basat en el dia de necessitats detectades‑oferta de serveis. Des d’aquesta base es poden construir polítiques locals de joventut sòlides i eficaces, a partir de la implantació de figures professionals d’acompanyament al territori, que a través de la relació socioeducativa estableixen vincle amb adolescents i joves i poden fer intervencions d’impacte a diversos nivells i amb diferent intensitat. Es proposen estratègies pel canvi de paradigma i per a la migració esglaonada cap al paradigma d’acompanyament
Obstetric violence: perspectives from mothers, midwives, and obstetricians
No full textBackground: According to the World Health Organization (WHO), the majority of the 140 million annual births occur without complications. Women desire a positive birth experience based on respectful care, clear information, and emotional support, which enables them to make informed decisions and maintain control over their reproductive process. However, many women experience disrespectful or abusive treatment during obstetric care, with lasting consequences for both their physical and mental health. This study explores the factors that influence respectful maternal care and the phenomenon of obstetric violence, as perceived by mothers, midwives, and obstetricians. Methodology: A qualitative study using a phenomenological approach was conducted in eight public and private hospitals in the Girona Health Region (Catalonia, Spain) between 2021 and 2022. In-depth interviews were conducted with eight mothers and eight healthcare professionals (midwives and obstetricians) selected through purposive sampling. The interviews were transcribed verbatim and analysed using thematic analysis to identify meaningful units and key themes. Results: The narratives collected allowed for the identification of key elements of non-respectful maternal care. A lack of information during pregnancy and childbirth emerged as a central concern for both mothers and professionals, affecting their sense of control and satisfaction. Poor communication with healthcare providers, particularly with anaesthesiologists and obstetricians, was perceived as a barrier to quality care. Mothers reported experiences of disrespect, the absence of informed consent for procedures such as episiotomies, and paternalistic treatment. Obstetricians showed resistance to the term 'obstetric violence,' while midwives recognized it as practices and attitudes that negatively affect the maternal experience. Conclusions: The discrepancy between professional perspectives and mothers' experiences highlights the urgent need for transformation in obstetric care. It is crucial to promote a care model based on evidence, effective communication, and respect for women's rights. Incorporating a gender perspective into healthcare training and strengthening public policies to ensure respectful obstetric care are essential measures to improve the quality of care and prevent obstetric violenceThis work was supported by the Women Catalonian Institute (Generalitat de Catalunya) with funding received from the Ministerio de Igualdad (Secretaría de Estado de Igualdad y contra la Violencia de Género), Spanish Government (Grant ID: ICD-2021-76
Oxidation-induced double aromaticity in periodo-polycyclic hydrocarbons
No full textThe doubly oxidized hexaiodobenzene [C6I6]2+ is a well-known example of a double aromatic molecule, exhibiting both π- and σ-aromaticity. In this study, a series of periodo-monocyclic molecules and their doubly oxidized forms were systematically investigated to explore the origin of their double aromaticity. These molecules were employed to provide insights into how the size and aromaticity of the central carbon atom ring influence the aromaticity of the resulting doubly oxidized structures. The knowledge gained in this study was subsequently applied to model periodo-derivatives of polycyclic (anti)aromatic hydrocarbons in which oxidation can induce additional σ-electron cyclic delocalization along the macrocyclic iodine ring, thus also achieving their double aromaticityS. R. and S. Đ. would like to dedicate this paper to students and teachers who stood against corruption and the collapse of the educational system in Serbia during the 2024–2025 academic year. S. Đ. and S. R. thank the Serbian Ministry of Science, Technological Development, and Innovation (Agreement No. 451-03-137/2025-03/200122). J. P. and M. S. thank the Spanish Ministerio de Ciencia, Innovación y Universidades (MCIN/AEI/10.13039/501100011033, projects: PID2023-147424NB-I00, PID2022-138861NB-I00, and CEX2021-001202-M) and the Generalitat de Catalunya (projects: 2021SGR442 and 2021SGR623 and ICREA Academia 2024 Prize to M. S.