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EU Digital Law. Art 11 E-Commerce D. Placing of the order
No full textMember States shall ensure, except when otherwise agreed by parties who are not consumers, that in cases where the recipient of the service places his order through technological means, the following principles apply: — the service provider has to acknowledge the receipt of the recipient's order without undue delay and by electronic means, — the order and the acknowledgement of receipt are deemed to be received when the parties to whom they are addressed are able to access them
EU Digital Law. Art 8 DSA No general monitoring or active fact-finding obligations
No full textNo general obligation to monitor the information which providers of intermediary services transmit or store, nor actively to seelc facts or circumstances indicating illegal activity shall be imposed on those providers
Corporate Responsibility: Understanding (and Misunderstanding) of Corporate Social Responsibility, Sustainability, and Solidarity
No full textThe primary purpose of this research is to differentiate the conceptualization of corporate sustainability (CS) from corporate social responsibility (CSR) and corporate solidarity. The objectives are threefold: first, we provide a literature review to show differences in the conceptualizations of the three phenomena and construct a corporate responsibility taxonomy; second, we perform a search of corporations’ annual responsibility reports and websites to investigate and analyse their understandings of CS, CSR, and solidarity, and how they apply these terms in business rhetoric; third, based on data collected from 93 different corporations, we investigate the fit between what our taxonomy of corporate responsibility declares and how corporations conceptualize CS, CSR, and solidarity. The results from this study suggest that there is a high degree of ambiguity as to what constitutes corporate responsibility. We conclude by presenting the implications of this study and suggestions for future research
Estudi de l’efecte de la introducció d’or(I) en la luminescència dels compostos organometàl·lics
No full textTreballs Finals de Grau de Química, Facultat de Química, Universitat de Barcelona, Any: 2025, Tutores: Laura Rodríguez Raurell, Andrea Pinto MartínezIn recent years, the interest in luminescent gold(I) complexes has increased significantly, due to the effect of this metal centre on modulating the light emission properties of the ligands attached to it. This is mainly due to two factors: relativistic effects and supramolecular interactions.
In this project, new bis(phosphane) gold(I) complexes have been prepared, aiming to study how the introduction of gold affects the luminescence of the ligands. The work involved the synthesis of the phosphanes with expected intrinsic luminescent properties, their corresponding gold(I) complexes, and the optimisation of these syntheses to obtain satisfactory yields. To evidence the correct formation of the target compounds, a variety of characterisation techniques were used (NMR, IR and HRESI-MS).
A basic photophysical characterisation was carried out using UV-vis and emission spectroscopies, quantum yields and lifetimes. These studies showed a significant increase in fluorescence emission and a redshift (ca. 10 nm) in every gold complex compared to their corresponding free ligand.
However, no phosphorescence was observed, even under nitrogen-saturated conditions. This suggests that either the energy gap between the first excited state and the triplet state is too large for the intersystem crossing to occur; that phosphorescence emission is only detectable at low temperatures or that there are other competitive mechanisms that compete with phosphorescence emission after population of the triplet excited state. To gain a deeper understanding of the observed phenomena, additional studies such as variable-temperature emission experiments and computational studies should be performed.
The obtained results suggest the potential of these gold(I) complexes use in optoelectronic devices such as light-emitting electrochemical cells (LECs). Understanding the correlation between structural aspects and photophysical properties in these systems could contribute to the development of next generation luminescent material
Identification of phytoestrogens in protein products from an alfalfa biorefinery
Get PDFTreballs Finals de Grau de Física, Facultat de Física, Universitat de Barcelona, Curs: 2025, Tutor: Fernando BenaventeBiorefineries are complex processing facilities dedicated to the sustainable transformation of biomass into value-added products. This project studies the influence of biorefinery processing conditions on the phytoestrogen composition of protein products derived from Medicago sativa L., commonly known as alfalfa. This leguminous plant has been traditionally used as a forage and is now gaining attention for its potential in producing proteins for human consumption. Phytoestrogens are bioactive secondary metabolites present in leguminous plants. Their structural similarity to the mammalian estrogen 17β-estradiol allows them to bind to estrogen receptors in animals. Given their capacity to produce both beneficial and adverse biological effects, identifying these compounds in alfalfa-derived products is critical to ensure consumer safety.
Ten alfalfa samples obtained from an industrial-scale biorefinery developed by Contento Trade Srl (Italy) were analyzed. These included nine mixed-protein and one fresh alfalfa samples, processed under varying conditions, including different harvest lots, drying delays, and drying techniques. Compound identification in the studied samples was performed using liquid chromatography-tandem mass spectrometry (LC-MS/MS), supported by a custom-built database of phytoestrogens and related metabolites.
Cross-referencing the obtained analytical data with the database enabled the tentative identification of 24 phytoestrogens across the samples. Comparative analysis showed that biorefinery processing conditions significantly affected the phytoestrogen profile of the mixed-protein products. Environmental stress factors affecting the fresh alfalfa material, such as morning frost exposure prior to harvest, altered these profiles. Regarding the biorefining drying conditions of the extracted mixed-proteins juice, delayed dryings of 16 or 36 hours were associated with higher phytoestrogen levels, indicating that immediate drying is preferable. In contrast, the drying technique (i.e. spray-drying or freeze-drying) had no significant effect on the final phytoestrogen composition. This finding supports the use of spray-drying as a more sustainable option for the biorefinery operation, given its lower energy and time requirement
Synthesis and characterization of Pd functionalized UiO-66 and UiO-67 MOFs for C-C Coupling reactions
No full textTreballs Finals de Grau de Química, Facultat de Química, Universitat de Barcelona, Any: 2025, Tutores: Maria Victoria Sanz Nebot, Petra Ágota SzilágyiMetal-organic frameworks (MOFs) have emerged as versatile porous materials thanks to their tuneable structures and compositional diversity. These features have positioned MOFs as promising candidates for a range of applications, particularly as platforms for heterogeneous catalysts. Among these, their potential to stabilize isolated metal atoms has attracted growing attention, opening new avenues in the development of single-atom catalysts[1].
Previous work carried out within the group of Szilágyi has demonstrated the immobilization of nanoclusters and single atoms of Pd incorporated into UiO-66 type metal-organic frameworks and has tested the catalytic activity of these Pd-laden MOFs in reactions such as the thermal hydrogenation of CO2. It was of interest to look for a reaction that demonstrates the catalytic activity of Pd single atoms embedded in functionalized UiO-66, and to investigate how Pd is incorporated in UiO-67 with new linkers. In this work, new functionalized linkers have been synthesized and incorporated into UiO-66 and UiO-67 MOFs, followed by metalation of the frameworks with Pd. Characterization has been done to confirm the structure of the material, and to understand the speciation of the incorporated Pd. The catalytic performance of the Pd immobilized frameworks for Stille coupling reaction has been assessed and the preliminary results are outlined.
Functionalized terephthalic acid-based linkers and BPDC have first been synthesized and integrated into the UiO-66 and UiO-67 topology following an established synthesis protocol[2]. Metalation of these modified MOFs was achieved through the incorporation and subsequent in-situ reduction of a Pd precursor, allowing the integration of neutral Pd atoms within the MOF pores. Comprehensive structural analysis was performed using techniques such as X-ray diffraction (XRD), thermogravimetric analysis (TGA), Brunauer-Emett-Teller (BET) surface area measurements, scanning electron microscopy (SEM), and microwave plasma atomic emission spectroscopy (MP-AES), enabling insights into the distribution and chemical state of Pd.
Advanced characterization confirmed that palladium was successfully incorporated into the MOFs in both UiO-66 and UiO-67 type MOFs. BET measurements show that UiO-67 type MOFs have much larger surface area due to the larger size of the linkers used. The catalytic performance of the synthesized UiO-66 type MOFs in the Stille coupling reaction has been examined and confirmed in this work, with the obtention of biphenyl using the synthesized MOFs as catalysts
A note on the local behavior of the Taylor method for stiff ODEs
No full textIn this note we study the behavior of the coefficients of the Taylor method when computing
the numerical solution of stiff Ordinary Differential Equations. First, we derive an asymptotic
formula for the growth of the stability region w.r.t. the order of the Taylor method. Then,
we analyze the behavior of the Taylor coefficients of the solution when the equation is stiff.
Using jet transport, we show that the coefficients computed with a floating point arithmetic of
arbitrary precision have an absolute error that depends on the variational equations of the solution, which can have a dominant exponential growth in stiff problems. This is naturally related to the characterization of stiffness presented by Söderlind et al. [32], and allows to discuss why explicit solvers need a stepsize reduction when dealing with stiff systems. We explore how high-order methods can alleviate this restriction when high precision computations are required. We provide numerical experiments with classical stiff problems and perform extended precision computations to demonstrate this behavior
Los autógrafos de Juan Pérez de Montalbán (1601-1608): El caso de El caballero del Febo
No full textEste trabajo presenta una primera aproximación a los autógrafos de Juan Pérez de Montalbán. Tras hacer un recorrido por las distintas marcas que el dramaturgo dejó en algunas de sus comedias, nos centramos en el análisis del Auto del caballero del Febo que, junto a los rasgos localizados en otros autógrafos, permitirá esclarecer estrategias de composición y comparar si son comunes a otros dramaturgos de la época
Rare Earth Element and Yttrium (REY) Hyper-Enriched Karst Bauxites of the Mercedes-Aceitillar Mining District, Sierra de Bahoruco,SW Dominican Republic
No full textRare earth elements, including yttrium (REYs), are the most sought-after among the so-called critical or strategic elements for the low-carbon energy industry. In the past decade, karst bauxite deposits have been targeted as potential nonconventional sources of these elements. The karst bauxite deposits from the Mercedes-Aceitillar mining district, classified as Fe-rich bauxites and bauxites sensu stricto, contain anomalously high REY contents oscillating between 514 and 28,787 ppm (median of 1,489 ppm), making them the most REY-enriched karst bauxites globally. Most of the samples studied are enriched in light rare earth elements (La-Nd; up to 7,449 ppm) and Y (up to 14,830 ppm). However, the most REY-enriched bauxites yield particularly high middle rare earth element (Sm-Gd; up to 4,579 ppm) and heavy rare earth element (Tb-Lu; up to 6,163 ppm) contents. In addition, the studied bauxites contain significant amounts of other critical metals, such as Sc and Ga (median of 62 and 39 ppm, respectively). The mineralogy consists predominantly of Al oxyhydroxides (mostly gibbsite), with variable amounts of Fe oxyhydroxides and kaolinite. The REY mineralogy in samples with high REY contents (>3,000 ppm) consists mainly of REY-bearing phosphates (e.g., monazite, xenotime, rhabdophane, churchite) and/or carbonates (bastnäsite group). In samples with moderate REY contents (<3,000 ppm), the main REY-bearing minerals are Al oxyhydroxides, onto which the REYs are most likely adsorbed. These findings indicate that the potential extraction of REYs and other critical metals, such as Sc and Ga, in the studied bauxites from the Mercedes-Aceitillar mining district could add, on average, an ~20% surplus to the revenue obtained from Al2O3 exploitation. The unprecedented REY contents discovered in these karst bauxites from the Dominican Republic present a unique opportunity to unravel critical metal concentration mechanisms in supergene environments and to develop new geochemical models for nonconventional REY deposits
Estudi de la interacció de marcadors fluorescents amb diverses estructures de l’ADN
No full textTreballs Finals de Grau de Química, Facultat de Química, Universitat de Barcelona, Any: 2026, Tutor: Raimundo Gargallo GómezThis project studies the interaction of four cyanine organic dyes (ID1-ID4) with different DNA structures, including the double helix, the G-quadruplex and the i-motif. For the characterisation of these interactions, molecular spectroscopic techniques such as UV-visible absorption, fluorescence and circular dichroism were used together with high-performance liquid chromatography.
UV-visible absorption provides relevant information on the aggregation of the dyes in aqueous solution, while fluorescence and circular dichroism allowed insight into the general modes of interaction of the ligands with the DNA structures.
The results show that the behaviour of the dyes varies depending on the substituents, although all four ligands can form H-dimers, only ID1 and ID3 form other H-type aggregates, such as trimers or tetramers.
Regarding DNA binding, ID1 and ID3 interact via an ordered π-π stacking with the terminal tetrads of Pu22T14T23, which is a parallel G-quadruplex, whereas ID2 and ID4 exhibit a disordered interaction due to steric hindrance from their substituents. In the case of the Py39wt i-motif, all ligands show a disordered interaction.
Thermal denaturation measurements indicate that dyes ID3 and ID4 significantly stabilise Pu22T14T23, whereas no ligand stabilises the Py39wt sequence.
HPLC analysis also confirms the formation of DNA:dye complexes and that this binding does not produce significant conformational changes in the DNA structure.
In summary, this study demonstrates that ligands can stabilise non-canonical DNA structures, particularly G-quadruplexes, making them interesting for future studies on the selective detection of G-quadruplexes and for the development of new therapeutic strategies for diseases such as cance