University of Burgos

Quercetin’s therapeutic potential is limited by its poor water solubility and rapid degradation. Natural clay minerals such as kaolinite present sustainable platforms for drug delivery, yet the molecular mechanisms of drug encapsulation are not fully understood. Specifically, the role of kaolinite’s structural polarity, its hydrophilic aluminol (001) and hydrophobic siloxane (00-1) basal surfaces, in selective drug adsorption remains unexplored. This study combines Monte Carlo sampling and Density Functional Theory (DFT) to provide the first quantitative, atomistic comparison of quercetin adsorption on both kaolinite surfaces. The results demonstrate a pronounced polarity-driven selectivity. Strong, exothermic adsorption (−206.65 kJ mol−1) occurs on the hydrophilic (001) surface, stabilized by a network of five hydrogen bonds. In contrast, the hydrophobic (00-1) surface exhibits significantly weaker sorption (−147.16 kJ mol−1), dominated by van der Waals interactions. Charge-transfer analysis shows that the hydrophilic (001) surface exhibits a net charge transfer of −0.198 e, approximately 2.4 times greater than that of the hydrophobic (00-1) surface (−0.083 e), consistent with differential electron density maps and partial density of states. By linking hydrogen bonding and charge transfer to adsorption energy, these results elucidate how surface polarity dictates drug encapsulation. This work establishes a predictive framework for designing kaolinite-based nanocarriers with optimized stability, bioavailability, and controlled release, guiding the development of sustainable drug delivery systems. It is noted that this DFT study models adsorption at 0 K using periodic slab models in a vacuum.

Large Vision–Language Models (LVLMs) have emerged as a powerful foundation for multimodal artificial intelligence, enabling unified reasoning over visual and textual information and achieving remarkable performance across a wide range of tasks, includ

Integrated science, technology, engineering, arts, and mathematics (i-STEAM) education has been recognized for its potential to promote interdisciplinary learning and connect scientific knowledge to socially relevant contexts. However, its implementation in school practices remains limited, often owing to conceptual ambiguities and a lack of sustained support for teachers. This study examines the role of participation in a community of practice (CoP) in facilitating the adoption of i-STEAM principles by public school teachers through collaborative lesson planning. Drawing on meeting transcripts, documents produced during the process, and interviews with participants, the analysis focused on the constitution of the CoP, the presence of i-STEAM elements in the teaching proposals, and the level of integration achieved. The results suggest that the CoP supported the development of more coherent and context-sensitive understandings of i-STEAM, while also promoting interdisciplinary design across diverse educational levels. These findings may also inform initiatives in other public education systems facing similar structural conditions, such as limited resources, disciplinary fragmentation, and restricted opportunities for collaborative curriculum development. The study highlights the value of CoPs as professional learning strategies and proposes a replicable analytical approach for evaluating how teachers engage with integrative pedagogies. Implications for teacher education and policy are discussed.

This paper proposes a new magnetic device with two variable inductors (VIs) integrated on the same core to reduce core losses and/or increase power density. The VIs can be independently controlled and have negligible influence on each other's operation. This magnetic device can be used in power electronics applications in which the design specifications require both inductances' modifications according to different operating conditions. This structure can also be analyzed for the application in one or more converters. In order to verify the theoretical analysis, LTspice simulations are carried out. Finally, this model has been implemented and tested at the laboratory and a reasonable match with the theoretical and simulation results is proven. In the proposed case study, the magnetic is formed by three E type core parts. However, the same procedure can be applied to similar magnetic structures using any core type and material, which increases its potential of use.

Viologen derivativesare widely used in the anolytes of aqueousorganic redox flow batteries (AORFBs). However, their applicationshave been restricted to neutral pH systems due to their fast degradationin basic media via a dealkylation process driven by a nucleophilicattack of hydroxide. In this study, a family of viologen-based anolytessuitable for alkaline systems is introduced, demonstrating that properlydesigned viologens can also be used in alkaline conditions. A varietyof N-aryl viologens are prepared and characterized,showing that the dealkylation process is prevented by bonding an arylgroup directly to the N-atom of the bipyridine core. Pairing B-2,5-DHPV for the anolyte and K4Fe­(CN)6 for the catholyte, a full alkaline AORFB having a nominal cell voltageat 0.98 V maintains stable capacity over 1400 continuous cycles withnearly 0.03%·h–1 capacity decay, which is avery acceptable value for a viologen in an alkaline medium. Our resultsenable the broadening of the range of viable organic anolytes foralkaline AORFBs.

SummaryPaleogenomic and radiocarbon data indicate that, excluding the temporal occupation of the islet of Lobos by Romans, the Canary Islands were permanently colonized by North Africans around the 3rd century CE. The archipelago was seemingly forgotten in the following centuries by Western societies until the beginning of the European Age of Exploration in the 14th century. In this study, we present 52 mitogenomes of ancient Canarian goats, including samples from the Roman site of Lobos, and the indigenous and colonial periods. We observe that the mitogenomes of indigenous goats are consistent with a North African origin for the human Canarian population. Goats from Lobos share the same haplotypes as the indigenous population, indicating that both settlements briefly overlapped, and goats in Lobos were probably taken from neighboring islands. We also detect temporal continuity from the indigenous period to the colonial and present-day goats, suggesting European settlers exploited this well-adapted species.

For decades, switched-capacitor converters (SCCs) have been widely studied and applied with the ability of high efficiency and power density. With the continuous enrichment and expansion of its application scenarios, the voltage conversion ratio and working efficiency of SCCs are facing increasingly high requirements. This paper proposes a high voltage step-down ratio switched-capacitor converter. This converter has obviously lower flying capacitor voltages than existing solutions, and thus, the effect of dc bias on multilayer ceramic capacitor (MLCC) is reduced and has a lower output impedance, thereby achieving higher working efficiency. In addition, the influence of capacitance on the output impedance of the converter is also analyzed in detail in this paper through mathematical derivation. In order to verify the theoretical analysis, an experimental prototype is built. The prototype can finally achieve a peak efficiency of 97.15%, which is significantly higher than existing solutions.

Most surface-enhanced Raman scattering (SERS) substratesreportedin the literature consist of plasmonic nanostructures, mainly basedon gold or silver. Although Cu plasmonic properties have been knownfor decades, Cu-SERS substrates remain limited by their limited chemicalstability. Nevertheless, many researchers claim that Cu-based SERSsubstrates should be revisited, as new synthetic strategies have ledto the improved stability of Cu nanostructures. Among these, the electrosynthesisof Cu nanomaterials has been proposed as an interesting approach becauseit allows the in situ generation of SERS substrates. Additionally,the combination of electrochemistry with operando Raman spectroscopy, also known as Raman spectroelectrochemistry,provides real-time information about the electrogenerated SERS substrates.In this work, we report the use of Cu-printed circuit boards to createan electrochemical platform, which can be used for the operando generation of Cu-based SERS substrates in chloride media. TheseSERS substrates exhibit great potential for the detection of tertiaryamines such as cocaine, fentanyl, paraquat, or adenine. A complementarystudy using bidimensional UV/vis absorption spectroelectrochemistrywas carried out to fully understand the processes occurring duringthe operando generation of the Cu-SERS substrates.

The neurocognitive impairments related to binge drinking and cannabis use in youth are widespread. Decision-making abilities might also be altered but previous studies focused on a disjoint exploration of individuals with binge drinking habits and with cannabis use, and did not control for major confounding factors (e.g., comorbid psychopathological states or general cognitive level), generating contradictory results. In view of the key role played by decision-making impairments in the development of addictive disorders, sounder explorations of decision making are needed in subclinical populations. A hundred university students divided in four groups (low drinkers, binge drinkers with no/low/high cannabis use, matched for demographic, psychopathological and cognitive abilities) performed the Iowa Gambling Task, a neuropsychological test measuring decision-making abilities under uncertainty/risk. When compared with low drinkers, binge drinkers with no/low cannabis use did not show decision-making deficits. Conversely, when combined with high cannabis use, binge drinking was related to impaired decision making, as shown by (a) lower total scores at the Iowa Gambling Task, indicating less efficient decision making under uncertainty/risk and (b) increased entropy in the choices made throughout the task, demonstrating a lower ability to develop efficient decision-making strategies. When controlling psychopathological states and general cognitive level, binge drinking per se is not associated with decision-making deficits. Conversely, when combined with intense cannabis use, it is related to marked decision-making impairments, which could promote the evolution toward substance use disorders. These results emphasize the importance of considering various forms of excessive substance use together when exploring their interaction with cognitive deficits in youth. We also identified the mechanisms underlying such neuropsychological deficits, paving the way for targeted interventions. (PsycInfo Database Record (c) 2025 APA, all rights reserved).