Alberto Sols Biomedical Research Institute
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Solubility and dissociation of ionic liquids in epoxides and cyclic carbonate by molecular dynamics simulation
No full textClimate emergency has led to the investigation of CO2 valorization routes. A competitive process included in this framework is the catalytic CO2 cycloaddition to epoxides, to produce cyclic carbonates. Halide-based Ionic liquids (ILs) have been postulated to be a competitive choice. Nevertheless, the structure-performance relation for different ILs is still a topic of debate, being the cation-anion dissociation constant a key descriptor. In this work, the ions effect is tackled by Molecular Dynamics (MD) simulations. Propylene oxide and carbonate force fields were tested and used for 1,2-epoxyhexane and hexylene carbonate force field construction, while ILs were modelled by the CL&P force field. Solubilities in an epoxide-carbonate medium were tested for ILs composed of [N4444+] or [N2222+] cations combined with the halide anions: Iodide [I−], Bromide [Br−] and Chloride [Cl−]. Results showed that [N2222+] cation-based ionic liquids were insoluble in the epoxide/carbonate medium, whereas [N4444+] cation-based ionic liquids demonstrated diffusion. Reaction medium interactions were studied between key atoms for experimentally soluble ILs. It was found that cation-anion interaction follows the catalytic activity trend, being [I−] the halide anion less associated with ([N4444+], [bmim+] and [emim+]) cations. A correlation between the first peak integration of the radial distribution functions and the experimental yields (including [N1111+][Br−]) could be established with a regression coefficient of 0.86. Additionally, [I−] based ILs displayed a better interaction between the cation and the epoxide oxygen, phenomena linked to epoxide activation and intermediates stabilization. Therefore, the path towards the understanding of this catalytic system has been widenedThe authors are grateful to Ministerio de Ciencia e Innovación of Spain (projects TED2021-129803A-I00 and PID2023-150532OB-I00) for financial support and Centro de Computación Científica de la Universidad Autónoma de Madrid for computational facilities. SDA aknowledges the FPI Grant (PREP2023-001656) from Ministerio de Ciencia e Innovación, Agencia Estatal de Investigación and Fondo Social Europeo Plus. JA and FJB also acknowledge funding from Ministerio de Ciencia e Innovación (projects PID2021-125081NB-I00 and PID2024158030NB-I00) and Universidad de Huelva (P.O. FEDER EPIT1282023), both co-financed by EU FEDER fund
Clarification of olive juice by α-alumina microfiltration membranes with enhanced packing density
No full textThe development of innovative designs has enabled the creation of new-generation mineral membranes with enhanced filtration packing densities, improving their competitiveness against polymeric membranes. This study evaluates the performance of two α-Al2O3 membranes with mean pore sizes of 800 and 600 nm and a filtration packing density of 184 m2.m−3, focusing on their operational parameters and the quality of olive juice clarification. Filtration with the 800 nm membrane achieved 2.4 times higher productivity than the 600 nm membrane. However, it left 14–19 NTU of haze in the final product and was more prone to fouling. In contrast, the 600 nm membrane produced fully clarified juice (<2 NTU) and was more resistant to fouling. Clarification with both membranes didn't produce significant retentions of the majority of the 29 examined phenolic compounds. However, retentions of 7.0 to 7.5 % of total dissolved substances, likely polysaccharide colloids, and complete removal of residual oil were achieved. Both membranes were capable of catalyzing spontaneous hydrolysis reactions that produced a significant increase in the contents of tyrosol, hydroxytyrosol and verbascoside, with oleacein concentration rising by up to 893 % in the clarified juices. Industrial relevance: fresh olive juice is an excellent source of phenolic and secoiridoid antioxidants. However, converting it into a value-added product remains a challenge for the olive oil industry due to technical difficulties in its on-line processing. A critical bottleneck of this activity is the removal of suspended solid impurities. This study shows that α-Al2O3 microfiltration membranes with mean pore sizes of up to 600 nm are able to clarify a minimally pre-treated (by centrifugation at 17568.g) olive juice in only one step and with very high quality. The treatment is scalable for industrial applicationsWe thank the Consejería de Educación e Investigación from Comunidad de Madrid for the financial support of this study and the PhD contract (IND2022/BIO-23619) of Alba Gutiérrez-Docio. We acknowledge also Prof. Juan Fernández-Bolaños from Instituto de la Grasa (CSIC) (Sevilla, Spain) for the kind supply of 3,4-DHPG reference substance and Luis Fernando Torrijos Fernández de Yepes for improving the understanding of the original English version of the manuscrip
Penetrance of dilated cardiomyopathy in genotype-positive relatives
No full textTesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Medicina, Departamento de Medicina. Fecha de Lectura: 25-03-2025Se desconoce la penetrancia de la enfermedad en los familiares con genotipo positivo (G+) de familias con miocardiopatía dilatada (MCD) y las características asociadas con la aparición de la MCD en estos individuos. En este estudio se buscaba determinar la penetrancia de MCD en familiares G+ e identificar factores asociados al desarrollo de la misma. Métodos Se realizó un estudio retrospectivo donde se evaluaron 779 sujetos G+ (35,8±17,3 años, 459 [59%] mujeres, 367 [47%] con variantes en TTN), de variantes patogénicas o probablemente patogénicas (P/PP), familiares de probandos con MCD, sin fenotipo en la primera evaluación. Participaron 25 centros españoles. Tras una mediana de seguimiento de 37,1 meses (IQR:16,3-63,8), 85 individuos (10,9%) desarrollaron MCD (la tasa de incidencia fue: 28,5 (95%CI 23,1 - 35,3) por 1.000 personasaño). La penetrancia de la MCD y la edad de aparición de la MCD fueron diferentes según el grupo de genes subyacentes (Log-rank p=0,016 y p<0,001, respectivamente). En un modelo multivariable que excluía los parámetros de resonancia magnética cardiaca (RMN), los predictores independientes del desarrollo de MCD fueron: edad (HR por aumento de 1 año: 1,02; IC95%: 1,0 - 1,04), ECG anormal (HR: 2,13; IC95%: 1,38 - 3,29); presencia de variantes en genes sarcoméricos (HR: 1,92; IC95%: 1,05 - 3,50); menor fracción de eyección ventricular izquierda (FEVI) (HR por aumento del 1%: 0,86; IC95%: 0,82 - 0,90) y mayor diámetro diastólico final del ventrículo izquierdo (DTDVI) (HR por aumento de 1 mm: 1,10; IC95%: 1,06 - 1,13). El análisis multivariable en individuos con RMN realizada y secuencia de realce tardío de gadolinio (RTG) (n=360, 45%) identificó el RTG como un predictor independiente adicional del desarrollo de MCD (HR: 2,52; IC95%:1,43 - 4,45). Aproximadamente, el 11% de los familiares G+ desarrollaron MCD, tras un primer cribado negativo, durante una mediana de seguimiento de 3 años. La edad, un ECG anormal, una menor FEVI (%), un aumento del DTDVI (mm), presentar variantes P/PP en genes sarcoméricos y la presencia de RTG en la RMN se asocian a un mayor riesgo de desarrollar MC
Extensiones de anillos puramente inseparables
No full textTesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Matemáticas. Fecha de Lectura: 04-04-2025Purely inseparable extensions were originally defined in the setting of field extensions. They are an important object of interest in Commutative Algebra and have been studied extensively, in particular with a view to develop an analogue of the classical Galois theory established for separable field extensions. The notion of purely inseparable has been extended later to the setting of rings. Some authors have proposed different, but related, generalizations for this concept. This thesis studies purely inseparable extensions of rings following the perspective from by F. Pauer . His definition considers purely inseparable ring extensions as the smaller subclass of commutative ring extensions containing purely inseparable field extensions and that is closed by base change and faithfully flat descent.
This thesis is focused on deepening the notion of purely inseparable ring extension and on generalizing some of the properties and results that are already known for purely inseparable field extensions to this broader context. In particular, we study purely inseparable extensions of rings from the perspective of differential operators and purely inseparable towers of rings using properties of projective modules. The thesis consists of four parts, which include the contents of the work in collaboration with D. Sulca and O. Villamayor.
In the first part, we analyze the more general setting of finite extensions of rings A ⊆ C such that C is projective as an A-module. In particular, given such an extension we study some towers of rings A ⊆ B ⊆ C and we prove a generalization of the Jacobson-Bourbaki correspondence for finite field extensions to this class of extensions when Spec(A) and Spec(C) are homeomorphic.
The second part begins with the study of purely inseparable extensions of rings in the exponent one case, which were introduced by S. Yuan as Galois extensions. We review the relation of these extensions with derivations, Kähler differentials, p-basis and differentiably simple rings. We provide a new characterization for Galois extensions by considering derivations as differential operators of order one. Moreover, we define the Yuan functor that parametrizes Galois towers of rings, we prove that it is representable by an scheme and we study its geometric properties.
The third part is devoted to purely inseparable extensions of rings in general. We first review the original characterizations given by F. Pauer in terms of normal generating sequences and modules of differentials. Then we study these extensions from the perspective of differential operators and obtain the new characterization. We also use these techniques on differential operators to re-obtain a characterization involving the modules of principal parts. In addition, we study purely inseparable towers of rings and provide some sufficient conditions for a tower of rings A ⊆ B ⊆ C to be purely inseparable.
The final part addresses modular extensions, which are a subclass of purely inseparable extensions. We extend the original definition of modular extensions of fields to the setting of rings using the property of being linearly disjoint. We prove that these extensions are exactly the purely inseparable ring extensions that satisfy certain conditions on linearly disjointednes
The Pedagogy of Death and education in the wake of the pandemic: Implications for comprehensive teacher education encompassing awareness and the biographical dimension
Get PDFThe pandemic has had a global impact on society and, consequently, also on schools. The aim of this study was to explore both teachers’ attitudes toward an education that includes death, and the impact of the pandemic on the treatment of death in the classroom. A survey using the DEAS-T instrument was administered to a total of 192 teachers from Spanish schools. Among the most salient results were: (1) participants had a moderately positive attitude toward the Pedagogy of Death, with influential variables such as gender, teachers’ academic profiles, and consequences of the pandemic; (2) the pandemic had made the subject of death somewhat more present in the classroom. Comprehensive teacher training in the Pedagogy of Death, encompassing awareness of the educational potential of death, didactic competences, and the biographical dimension of the teacher, is called fo
Electron-phonon coupling and phonon dynamics in single-layer NbSe2 on graphene: The role of moiré phonons
Get PDFThe interplay between substrate interactions and electron-phonon coupling in two-dimensional (2D) materials presents a significant challenge in understanding and controlling their electronic properties. Here, we present a comparative study of the structural characteristics, phonon dynamics, and electron-phonon interactions in bulk and monolayer NbSe2 on epitaxial bilayer graphene (BLG) using helium atom scattering (HAS). High-resolution helium diffraction reveals a (9 × 9)0° superstructure within the NbSe2 monolayer, commensurate with the BLG lattice, while out-of-plane HAS diffraction spectra indicate a low-corrugated (3√3 × 3√3)30° substructure. By monitoring the thermal attenuation of the specular peak across a temperature range of 100 to 300 K, we determined the electron-phonon coupling constant (λHAS) as 0.76 for bulk 2H-NbSe2. In contrast, the NbSe2 monolayer on graphene exhibits a reduced λHAS of 0.55, corresponding to a superconducting critical temperature (TC) of 1.56 K according to the MacMillan formula, consistent with transport measurement findings. Inelastic HAS data provide, besides a set of dispersion curves of acoustic and lower optical phonons, a soft, dispersion less branch of phonons at 1.7 meV, attributed to the interface localized defects distributed with the superstructure period, thus termed Moiré phonons. Our data show that Moiré phonons contribute significantly to the electron-phonon coupling in monolayer NbSe2. These results highlight the crucial role of the BLG in the electron-phonon coupling in monolayer NbSe2, attributed to enhanced charge transfer effects, providing valuable insights into substrate-dependent electronic interactions in 2D superconductorsThis work has been partially supported by the Spanish Ministerio de Ciencia e Innovación under projects PID2019-109525RB-I00 and PID2023-147466OB-C21. D.F. acknowledges financial support from the Spanish Ministry of Economy and Competitiveness, through the “María de Maeztu” ACS Nano www.acsnano.org Article https://doi.org/10.1021/acsnano.4c16399ACS Nano 2025, 19, 8895−89038901 Programme for Units of Excellence in R&D (CEX2018-000805-M). M.M.U. acknowledges support by the ERC Starting grant LINKSPM (Grant 758558) and by grant PID2023-153277NB-I00 funded by the Spanish Ministry of Science, Innovation and Universitie
Hybrid zirconium-lanthanum metal-organic frameworks for solar-driven sulfamethoxazole degradation
Get PDFNovel mixed Zr-La MOFs with varying Zr:La ratios (3 ̶ 20 wt% La) based on UiO-66-NH 2 2 (Zr) were synthesized by a solvothermal approach and assessed for the solar degradation of sulfamethoxazole, a widely detected antibiotic in urban wastewater. The influence of La doping on the structural and photocatalytic properties was thoroughly investigated. All synthesized materials depicted the crystallographic structure of the UiO-66-NH 2 , incorporation of La 3+ leading to partial substitution of Zr 4+ with the in the [Zr–O] clusters, which resulted in a slight lattice contraction and restricted crystal growth. Photocatalytic tests revealed that the MOFs with lower La content exhibited significantly enhanced activity compared to the parent UiO-66-NH 2 photodegradation rate constants (k app , with sulfamethoxazole ) up to two times higher. Mechanistic studies using scavengers and electron spin resonance spectroscopy identified •O 2– and holes as the predominant reactive species responsible for sulfamethoxazole photodegradation. This study demonstrates that low-level La doping is an effective strategy to boost the photocatalytic efficiency of UiO-66-NH 2 for emerging pollutant removal under solar lightThe authors gratefully acknowledge financial support from the Spanish State Research Agency (Project PID2022-141056OB-I00). Authors also thank the Research Support Services of the University of Extremadura (SAIUEx) for their technical and scientific assistance, and the external services of the Autonomous University of Madrid (SIdI) for additional support. We are grateful to Dr. Duan from the University of Adelaide (Australia) for carrying out the ESR assay
Attitudes of native and foreign Spanish speakers towards language varieties
No full textAn analysis is presented on the linguistic beliefs and attitudes of 80 students and graduates of Hispanic Philology, Translation or similar: 40 native Spanish speakers and 40 foreign speakers (Brazilians). Specifically, four varieties of Spanish (Andean, Mexican, Castilian, and Rioplatense) were studied, as well as the voices of Brazilians speaking in Spanish. The study was conducted based on the theoretical approaches to linguistic beliefs and attitudes developed by Lambert and Lambert (1975), López Morales (1979, 2004), Gómez Molina (1987), Blas Arroyo (2005), Moreno Fernández (2009), and Garret (2010), among others. For this, an analysis of the prestige of the varieties was carried out using the matched-guise technique and open-ended questions; the degree of identification of the varieties was measured through recordings, and the (in)security of the participants in the study was examined through an open-ended question. The results indicate that the Castilian and Rioplatense varieties are the most prestigious for native Spanish speakers, while the Mexican and Rioplatense varieties are the most prestigious for Brazilians; that native Spanish speakers are better at identifying Spanish varieties than Brazilians; and that the latter have a higher level of linguistic insecurity than the native Spanish speaker
Identifying individuals from their brain natural frequency fingerprints
No full textThe data used this study are available in OMEGA: The Open MEG Archive (doi:10.1016/j.neuroimage.2015.04.028)All codes for preprocessing and data analysis are available at https://github.com/necog-UAMNeural oscillations are critical for brain function and cognition. Thus, identifying the typical or natural frequencies of the brain is an important step in understanding its functional architecture. Recently, a data-driven algorithm has been developed for mapping these frequencies throughout the cortex, free of anatomical and frequency-band constraints, but its robustness is limited to group-level analyses. Here, we adapt this algorithm to improve the single-subject maps of natural frequencies derived from magnetoencephalography and validate them using the fingerprinting technique. Modifications to the original method included (1) increasing the number of power spectra assigned to each k-means cluster, and (2) smoothing across neighboring voxels. Our results show high accuracy in individual identification within single sessions and across sessions separated by over four years. This demonstrates the stability and reliability of the single-subject mapping of natural frequencies, enhancing opportunities for identification of pathological variations in the intrinsic oscillatory activity of individualsThis work was supported by Ministerio de Ciencia e Innovación/Agencia Estatal de Investigación, Spain/FEDER/FSE+, UE (MCIN/AEI/10.13039/501100011033/FEDER/FSE+, UE; PID2021-125841NB-I00 to AC); and the Comunidad de Madrid, Spain (IND2022/SOC-23652 to LA
Interacción luz-materia en sistemas fotónicos de Weyl
No full textTesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Física Teórica de la Materia Condensada. Fecha de Lectura: 08-02-2024Esta tesis tiene embargado el acceso al texto completo hasta el 08-08-2025Light-matter interactions play a central role in understanding the world around us.
Their study has fueled significant advances enabling the expansion of the frontiers
of knowledge and the design of novel technological applications. In this context, the
extension of the ideas associated with the topological phases of matter to the photonics
realm stands as an exciting challenge since they can modify the way in which these
interactions take place. Topological light-matter interfaces can be exploited to obtain
robust chiral quantum networks or to find new ways of probing topology in photonic
platforms. At the same time, they can give rise to exotic regimes of interaction as
a consequence of the non-linear character of the emitters that comprise the system.
This includes the photonic counterparts of strongly interacting electronic states, such
as the fractional quantum Hall effect.
Among the zoo of topological photonic phases, Weyl photonic systems represent
a paradigmatic example in the three-dimensional case. The bulk excitations of this
gapless phase feature a dispersion relation that can be described by massless solutions
of the relativistic Dirac equation. Furthermore, its topological nature is directly manifested
by the presence of Fermi arc surface states that take the form of open curves
in the surface Brillouin zone connecting the projection of Weyl points with different
chirality. This thesis is devoted, precisely, to the characterization of the interplay
between matter and such topological Weyl photons.
We first study the coupling of one or more emitters to the bulk modes of a
Weyl photonic bath. Using a lattice model to describe the photonic environment,
we study the exact dynamics of the system. We find that the vanishing density of
states displayed by a type I Weyl photonic phase facilitates the emergence of an
atom-photon bound state. The latter defines a hybrid light-matter state featuring a
power-law localization of its photonic part around the emitter’s position. We show
that this atom-photon bound state mediates long-range, tunable, and robust interactions
among emitters when more than one of them is embedded within the Weyl
medium.
Then, we investigate the quantum optical behavior of an interface formed by a set
of emitters coupled to the Fermi arc surface modes. We demonstrate that such an interface
can be used to probe the topological edge states by imaging the corresponding
Fermi arcs. We also report on how this platform can be harnessed to design perfect
quantum state transfer protocols or to entangle multiple emitters. Our findings evidence
the great potential of the Fermi arc surface states to be leveraged for quantum
technological applications.
Finally, we explore a particular implementation of a Weyl photonic system in a
subwavelength atomic array. We show that the dipolar interactions governing the
behavior of the atomic ensemble when it is arranged following a cubic body-centered
geometry give rise to a Weyl phase characterized by the presence of a single pair of
frequency-isolated Weyl points. This condition permits to access the Weyl modes
through the integration of additional impurity emitters resonant with the Weyl frequency.
Besides, we study the edge modes of the system. These are affected by the
collective dissipation effects induced by the interference of the atomic array’s spontaneously
emitted photon