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¿Qué modelos de propiedad ampara la Constitución? (O cómo imaginamos el derecho de propiedad en los cincuenta próximos años?
No full textEsta contribución pretende abordar cómo se articula el derecho de
propiedad a partir de su plasmación en el art. 33 de la Constitución española (CE), con la relación/correlación entre Derecho constitucional y
Derecho privado stricto sensu; también reflexionar sobre el derecho de
propiedad en el futuro, en un mundo digitalizado y digitalizable por momentos
Síntesi de complexos de coordinació derivats de macrocicles nitrogenats. Estudi magnètic
No full textTreballs Finals de Grau de Química, Facultat de Química, Universitat de Barcelona, Any: 2025, Tutora: Júlia Mayans Ayats“In the last decade, S=1/2 systems of Cu (II) complexes and Cu (II) ions in the solid state have been found to exhibit slow magnetic relaxations. With the aim of progressing toward the entanglement of spin states and quantum computing using spin qubits, a greater number of studies on molecule-based spin qubits that exhibit magnetic interactions will be conducted and will be of increasing importance from now on.” (2)
Nickel (II), similarly to copper (II), is a transition metal cation that can show interesting magnetic behaviour when is coordinated with suitable ligands. With an electronic configuration of d8, Ni (II) tends to form stable octahedral geometries, where the presence of unpaired electrons contributes to the magnetic susceptibility of the complex. In polynuclear systems, Ni (II) allows the study of magnetic interactions such as antiferromagnetism, especially when metal centres are connected through bridging ligands like oxalate. Also, its smaller contribution to the Jahn-Teller effect compared to Cu (II) usually results in less distorted structures, which makes the structural and magnetic analysis easier to interpret. (3)
This project is focused on the synthesis of new coordination compounds using copper (II) and nickel (II) salts with nitrogenated macrocycles as ligands, combined with oxalate or benzoquinone bridges. The main objective is to create and study these complexes for their potential magnetic properties, with possible future applications in molecular magnets or quantum technologies.
During the project, six different compounds were successfully synthesised and characterized. The ligands used (232-N4 and 323-N4) helped to build coordination structures with varying geometries. Techniques like IR spectroscopy and X-ray diffraction were used to analyse their structures. In parallel, their magnetic behaviour was studied using SQUID magnetometry, which allowed precise measurements of magnetization and magnetic susceptibility. Additionally, Electron Paramagnetic Resonance (EPR) was carried out.
The complexes showed interesting structural details and magnetic patterns depending on their composition.
Concepts such as magnetization, susceptibility, and anisotropy of the g-factor are essential to interpret the results correctly.
Through these analyses, it is possible to relate geometric features of the complexes with their magnetic responses, which is a key aspect in the field of molecular magnetism.
Although some reactions didn’t give products (which are in the appendix 1), the project contributed valuable knowledge. It supports basic research in coordination chemistry and molecular magnetism, which can be useful in high-density data storage, quantum computing, or advanced sensors in the futur
Conditioning access to the European Union market on carbon footprint: the Carbon Border Adjustment Mechanism
No full textThe European Union (EU) is using different trade instruments to promote global decarbonization, including unilateral measures to condition the access to the EU’s market of certain products originating from third countries depending on their carbon footprint. This chapter is devoted to the recently adopted Carbon Border Adjustment Mechanism (CBAM), aimed at reducing the risk of the so-called carbon leakage. The logic of this measure is that EU importers of certain products originating in third countries (such as steel, aluminium, cement…) will have to acquire public certificates (CBAM certificates) for carbon emissions embedded in imported goods, based on the real emissions released during the production process in the country of origin. The EU CBAM is very original, because to date no country has implemented a big measure of this kind. But the EU CBAM is also very controversial, as certain countries (mainly emerging economies) question whether it can be compatible with the multilateral trading system and with some global rules on climate change, such as the principle of common but differentiated responsibilities. This chapter will therefore delve into the currently heated debate on the legal compatibility of the EU CBAM with these international regimes, observing also its systemic implications
Chemical exposure in childhood: A. study on organophosphate flame retardants and plasticizers
No full textHumans are exposed daily to contaminants such as organophosphorus flame retardants (PFRs), legacy plasticizers (LPs), and alternative plasticizers (APs). To date, most biomonitoring studies in children have only focused on analysis of LP metabolites and a subset of PFRs and APs. This study investigated exposure to multiple PFRs, LPs and APs in the ENVIRONAGE birth cohort quantifying 13 PFR metabolites in 655 urine samples, while we measured 8 LP and 13 AP metabolites in urine of 328 children. For PFRs, more than 50% of children were exposed to TNBP, TPHP, TDCIPP, TCIPP and EHDPHP. More than 93% of children were exposed to the measured LPs (DEP, DiBP, DnBP, BBzP and DEHP), while for APs more than 50% of children showed exposure to DEHA, DEHTP, DINCH and DIDP. Concentrations of PFR metabolites were higher in summer, while the presence of a pet in the house was associated with higher LP metabolite concentrations. Risk characterization ratios (RCRs) for single compounds and hazard indices (HIs) for compound classes suggested no risk for adverse health effects due to PFR exposure. For LPs, two children showed a HI above 1, while for APs, ten children had a HI above 1. The results indicate widespread exposure to PFRs and plasticizers, with most children being exposed to levels that are considered safe. However, the current study confirms a shift in exposure from LPs to APs, implying the need for further research on exposure to multiple APs in future studies
Elucidation of the Biosynthesis of Rickiols
No full textTreballs Finals de Grau de Química, Facultat de Química, Universitat de Barcelona, Any: 2025, Tutors: Russell Cox, Nick GerlachRickiols are a novel class of fungal macrolides with promising antibiotic properties, particularly against Gram-positive bacteria.
Despite their structural elucidation in 2017, the genes responsible for their biosynthesis in the filamentous fungus Hypoxylon rickii remained unidentified. This thesis aims to elucidate the biosynthetic gene cluster (BGC) of Rickiols and functionally validate it via heterologous expression in Aspergillus oryzae, through molecular cloning and transformation. The genes encoding core enzymes, such as highly reducing polyketide synthase (hrPKS), thioesterase (TE); and genes encoding tailoring enzymes like cytochrome P450, short-chain dehydrogenase/reductase (SDR), and flavin-dependent monooxygenase (FMO), were introduced into A. oryzae using
synthetic biology tools. The expression of these genes led to the successful production of several Rickiols. The presence and chemical structures of the new compounds was confirmed by HPLC-MS and NMR. These findings lay the groundwork for the future development of scalable microbial production systems that could be used to generate new antibiotics or chemical variants with enhanced therapeutic potential, avoiding the need for chemical synthesi
EU Digital Law. Art 10 Introduction
No full textThe creation of a regulatory framework for the supply of digital content has been a central and ever-growing feature of the EU legislative agenda. The drive towards an EU Digital Market has already resulted in a wealth of legislation harmonising various aspects of the laws of EU Member States
EU Digital Law. Art 4 DSA 'Mere conduit'
No full textWhere an information society service is provided that consists of the transmission in a communication network of information provided by a recipient of the service, or the provision of access to a communication network, the service provider shall not be liable for the information transmitted or accessed, on condition that the provider..
Resolution of complex mixtures of duplex and antiparallel triplex DNA structures by capillary electrophoresis and multivariate analysis
No full textTriplex DNA structures, which are formed by the addition of an extra strand to a target B-DNA duplex, have attracted increasing interest due to their analytical and therapeutic applications. These structures are classified into parallel and antiparallel, depending on the orientation of the Triplex-Forming Oligonucleotide (TFO) relative to the B-DNA duplex. Whereas the formation of parallel triplexes is easily detected by monitoring spectral changes in the UV region, the formation of antiparallel triplexes produces small or even no spectral variations, which makes their detection difficult and uncertain.In this study, we propose the use of capillary electrophoresis with ultraviolet absorption spectrophotometric (CE-UV) detection combined with the multivariate curve resolution-multivariate-alternating least squares (MCR-ALS) chemometric method to analyze mixtures of DNA sequences capable of forming mixtures of B-DNA duplex and triplex antiparallel structures. Rapid and reproducible CE-UV analysis in hydroxypropylcellulose (HPC)-coated capillaries are done in a pH 7.4 buffer containing Mg(II) for the stabilization of the intermolecular species. Spectra measured from 220 to 300 nm along the CE-UV analysis of individual DNA strands and of their mixtures at different ratios are merged into an augmented data matrix. This is later analyzed with MCR-ALS to deconvolute characteristic pure spectra and electropherograms for each one of the CE-UV analysis considered. This procedure has allowed the resolution and detection of DNA species present in mixtures of DNA strands capable of forming duplexes, as well as antiparallel triplex structures
Fate and degradation of methoxychlor in a contaminated aquifer: Insights from dual carbon-chlorine isotope analysis and isomeric fraction
No full textThe combined use of isomeric fraction (IF) and multi-element compound-specific isotope analysis (ME-CSIA) was evaluated for the first time to assess the fate and degradation of methoxychlor in the environment. The concentration and carbon and chlorine isotope composition of methoxychlor and its transformation products were monitored in water and solid phases of a fractured aquifer. The results from the interception trenches water samples demonstrated that induced alkaline conditions promoted alkaline hydrolysis. Natural attenuation of methoxychlor isomers was evidenced by carbon and chlorine isotopic fractionation. The field C-Cl isotope slope (ΛC/Cl = 0.42 ± 0.06; R² = 0.98) was statistically indistinguishable (p > 0.05) from that obtained in a previous experiment (0.44 ± 0.14), confirming the occurrence of reductive dechlorination of methoxychlor isomers. P,p’-methoxychlor δ13C values in groundwater samples revealed variations linked to rainfall patterns. The extent of p,p'-methoxychlor biodegradation was calculated to be greater than 89% across the monitoring period. The combined use of CSIA and IF evidenced that alkaline hydrolysis and reductive dechlorination did not exhibit isomeric selectivity. Differences in IF values between slurry and water samples, as well as between upstream and downstream wells, suggested variations in the environmental behaviour of the p,p’ and o,p’-isomers, likely due to differing water solubilities. Overall, ME-CSIA proved to be a valuable tool for identifying, quantifying, and tracing methoxychlor degradation in this aquifer. Additionally, IF provided insights into the distinct environmental behaviour of the p,p'- and o,p'-isomers. These tools offer crucial information, valuable for decision-makers in developing remediation strategies for methoxychlor-contaminated sites
Meso-tetra(4-fluorobenzoïl) porfirina: síntesi, caracterització i estudi de les seves aplicacions en catàlisi fotoredox amb llum visible
No full textTreballs Finals de Grau de Química, Facultat de Química, Universitat de Barcelona, Any: 2026, Tutor: Albert Moyano BaldoireVisible-light photoredox catalysis has become a powerful tool in organic synthesis, with an increasing interest in the development of efficient organophotocatalysts that avoid the use of scarce and/or toxic transition metals. Among these, porphyrins have attracted attention due to their tunable photophysical and redox properties. Previous studies by our research group demonstrated that both the electronic nature and the position of substituents on the porphyrin framework play a crucial role in modulating these properties and have led to the identification of meso-tetra(4-fluorobenzoyl)porphyrin as a particularly promising candidate due to the great facility of reduction of its excited state. In this context, the aims of this Bachelor’s thesis were to achieve a detailed characterization of this porphyrin, to investigate its photophysical behavior, and to evaluate its applicability as a visible-light photoredox catalyst. The target porphyrin was fully characterized by NMR spectroscopy, including HSQC experiments, allowing complete signal assignment (1H and 13C). Its singlet and triplet excited-state lifetimes were also determined . The compound was then applied as a photocatalyst in the addition of alkyl radicals, generated from 4-isopropyl-substituted Hantzsch esters, to p-substituted β-nitrostyrenes under visible-light irradiation. The reactions afforded mixtures of Giese addition and of nitro substitution products, whose distribution depends both on the irradiation wavelength and on the electronic nature of the styrene substituent. These results can be accounted for by a reductive quenching photoredox cycle involving initial oxidation of the Hantzsch ester by the excited porphyrin. While control experiments revealed that catalyst-free reactions can occur at wavelengths below 500 nm through direct excitation of the Hantzsch ester, at longer wavelengths the presence of the porphyrin photocatalyst becomes essential