Articles publicats en revistes (Física Aplicada)

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Laser-Induced Vertical Graphene Nanosheets for Electrocatalytic Hydrogen Evolution
(2024-09-25) Chaitoglou, Stefanos; Ma, Yang; Ospina, Rogelio; Farid, Ghulam; Serafin, Jarosław; Amade Rovira, Roger; Bertrán Serra, Enric
Efficient and affordable electrocatalysts are fundamental for the sustainable production of hydrogen from water electrolysis. Here, an approach for the rapid production of laserinduced vertical graphene nanosheets (LIVGNs) through the exfoliation of the graphite foil under laser irradiation is presented.The density of the formed LIVGNs is ∼3 per 100 μm2. On leveraging the inherent flexibility and conductivity of the graphite foil substrate, the resulting LIVGNs exhibit a 2.2-fold increase incapacitance, making them promising candidates for electrode applications. The laser-induced surface reconstruction introduces abundant sharp edges to the LIVGNs, enhancing their electrocatalyticpotential for hydrogen evolution. In electrocatalytic hydrogen evolution tests in acidic media, the LIVGNs demonstrate superior performance with a remarkable decrease in the required overpotential at 10 mA cm−2, from −555 mV for the pristine graphite foil to −348 mV for LIVGNs. This improvement is attributed to the active sites provided by the sharp edges, facilitating hydrogen species adsorption. Furthermore, the hydrophilic behavior of LIVGNs is enhanced through the anchoring of oxygencontaining groups, promoting the rapid release of the produced hydrogen bubbles. Importantly, the modified LIVGN electrode exhibits long-term stability across a wide range of current densities during chronoamperometry tests. This research introduces a transformative strategy for the efficient preparation of vertical graphene sheets on conductive graphite foils, showcasing their potential applications in electrocatalysis and energy storage.
Hydrophilic Janus Micelles from an ABC Triblock Copolymer
(Wiley-VCH, 2026-02-23) Muñoz López, José María; Hu, Lei; Wang, Haomin; Tian, Xiaohe; Ruiz-Perez, Lorena; Battaglia, Giuseppe
We describe the creation of an amphiphilic triblock copolymer that drives lateral phase separation within micelle coronas. The design combines a hydrophobic poly(lactide) (PLA) core ‑forming block with two distinct hydrophilic segments: poly(ethylene glycol) (PEG) and poly( N ‑vinylpyrrolidone) (PVP). In water, the copolymer assembles into spherical micelles, confirmed by cryogenic TEM and multi ‑angle light scattering. Selective end ‑labelling of PVP with an electron ‑dense iridium complex enabled unstained TEM imaging, revealing clear contrast asymmetry that locates PVP to a single hemisphere of the corona. Complementary 2D1 H-Nuclear Overhauser Effect Spectroscopy (1 H ‑NOESY) NMR confirmed this Janus ‑type segregation of PEG and PVP. These results demonstrate how molecular architecture can encode asymmetry into soft nanostructures, offering a versatile route to polymer ‑based Janus nanoparticles with dual surface functionality and broad technological potential.
Characterization of high-intensity storms in the Metropolitan Area of Barcelona (2014–2022)
(MDPI, 2025-12-28) Esbrí, Laura; Rigo, Tomeu; Llasat Botija, María del Carmen
Urban coastal areas along the Mediterranean are exposed to short-duration convective rainfall, producing infrastructure disruptions and flood-related impacts. This study analyzes 45 rainfall episodes in the Metropolitan Area of Barcelona between 2014 and 2022, combining radar products, rain gauge observations, and urban-scale impact datasets. Storm radar tracking enabled the identification of key spatiotemporal features and assessment of short-term forecasting performance. Convective cells were typically short-lived, lasting less than 30 min in most cases. The main goal of the research has been the comparison between VIL density (DVIL) radar field and short-duration rainfall intensity provided by rain gauges. This is the first study comparing both data types, being a pioneer in this field. We have found a linear relationship between both data types, with weaker values for larger values. More persistent cells had higher DVIL values, observing a difference in behavior with a break point at 2 g/m3. The tracking and nowcasting system were evaluated based on its ability to anticipate convective precipitation. It achieved good scores values (POD of 0.73 and FAR of 0.33), considering the difficulties of tracking this type of convective system. Finally, false alarms associated with elevated DVIL values suggested the difficulty of capturing storm severity by surface-based precipitation measurements.measurements.
Analyse d’une alerte massive arrivée tardivement lors des inondations survenues à Valence (Espagne) le 29 octobre 2024.
(Centre national de la recherche scientifique (CNRS), 2025-10-15) Douvinet, Johnny; J.; Gallet, Maé; Vinet, Freddy; Llasat Botija, María del Carmen
Les inondations survenues le 29 octobre 2024 au sud de Valence (Espagne) ont entraîné un lourd bilan humain (229 personnes décédées) et matériel (22 milliards d’euros de dégâts). Les intensités des pluies ont entraîné des réactions hydrologiques brutales et violentes. Mais de nombreux acteurs ont toutefois remis en cause l’arrivée tardive de l’alerte à la population : la première alerte a été diffusée sur les téléphones portables à 20h11, alors que les inondations avaient débuté depuis plusieurs heures. Afin de comprendre les raisons du retard de l’alerte, cet article propose de replacer la chronologie des faits établis à partir de différentes données : les horaires des vigilances météorologiques, les intensités des pluies, les débits mesurés à certaines stations et les appels vers les centres de secours. La manière dont le dispositif ES-Alert a été considéré et le contenu des messages d’alerte ont aussi été étudiés. Les résultats confirment que l’alerte aurait dû être activée plus tôt afin de réduire le nombre de victimes. Ce retour d’expérience est par ailleurs riche d’enseignements sur le plan opérationnel (pour éviter d’alerter tardivement face à de futures inondations) et sur le volet scientifique (pour réfléchir à des stratégies d’alerte plus adaptées à la dynamique spatio-temporelle des inondations).
Decoding the Conformation of Polylactic Acid in Block Copolymer Micelles
(American Chemical Society, 2026-01-28) Muñoz-López, José; Tuveri, Gian Marco; Barbieri, Valentino; Basile, Marco; Cosenza, V.; Lorenz, Christian D.; Ruiz-Perez, Lorena; Battaglia, Giuseppe
Understanding how molecular features dictate the self-assembly of amphiphilic block copolymers into well-defined nanostructures is essential for the rational design of advanced soft materials. However, the large number of interdependent parameters involved, such as particle size, aggregation number, interfacial curvature, and molecular weight, makes it challenging to establish general design principles. Here we establish a scaling-based framework for PEG-b-PLA micelles with a fixed hydrophilic−hydrophobic ratio. Systematic variation of molecular weights enables precise control of micelle size and aggregation number, quantified by DLS, cryo-TEM, and MALS.
Improving Extreme Precipitation Forecasts in Catalonia (Spain) Using Analog Methods: A Comparison with the GFS Model
(Elsevier B.V., 2025-11-21) Guzzon, Carlo; Marcos Matamoros, Raül; Llasat Botija, María del Carmen; Llasat-Botija, Montserrat
Flood forecasting in the Mediterranean region remains particularly challenging due to the localized and convectivenature of extreme precipitation events. This study evaluates the potential of analog-based methods (AMs)to enhance 24-hour precipitation forecasts for Catalonia (northeastern Iberian Peninsula), with the broaderobjective of supporting flood risk management and early warning systems. The tested AMs use geopotentialheight fields at 500 and 1000 hPa as predictors and differ in complexity, combining Weather-Type classification(WT), Seasonal Standardization (S), and the Perfect Prognosis (PP) framework, a novel configuration in analogbasedforecasting. Model performance was assessed against operational Global Forecast System (GFS) forecastsusing fifth-generation ECMWF Re-Analysis (ERA5) as reference, for both moderate and extreme precipitationevents associated with historical floods. Results show that AMs integrating Seasonal Standardization and thePerfect Prognosis framework markedly improve 24-hour precipitation forecasts relative to GFS, particularly inreproducing the intensity and spatial distribution of extreme events. These findings highlight the operationalpotential of enhanced AMs as efficient, data-driven complements to numerical weather prediction models,offering improved skill for flash-flood forecasting and impact-based risk management.
Roadmap on Optics and Photonics for Security and Encryption
(Institute of Electrical and Electronics Engineers (IEEE), 2025-12-01) Stern, A.; Wang, Xinyuan; Xia, T.; Xiao, Y.; Zhenwei, X.; Zhu, S.; Jana, A.; Lam, E.Y.; Long, G.-L.; Matoba, O.; Mi, Z.; Moon, I.; Nishchal, N.K.; Pan, D.; Peng, X.; Pinkse, P.W.H.; Javidi, B.; Carnicer González, Arturo; Ahmadi, K.; Awatsuji, Y.; Chen, Wanqi; Fournel, T.; Genevet, P.; Guo, J.; He, W.; Hebert, M.; Shi, Y.; Situ, G.
In 1994, Javidi and Horner published a paper in Optical Engineering that highlighted the ability of free space optical systems to manipulate sensitive data for authentication purposes. The underlying idea was effective yet surprisingly simple: an optical nonlinear joint transform using a random phase mask in both the input and the reference could produce a correlation peak to indicate whether the input object is authentic or not. This seminal paper fueled the development of this new discipline. After three decades, optical encryption and security have matured into a field that plays a central role in the development of photonics techniques. While the pioneering work was mainly focused on the field of optical information processing, nowadays, a broad spectrum of disciplines are contributing to developing security solutions, including nanotechnology, materials science, quantum information, and deep learning, just to cite a few. The present roadmap paper gathers 28 leading authors in the field from 21 academic institutions across nine different countries. It is organized into 17 sections which discuss the present and future challenges, state-of-the-art technology, and real-world solutions to address the security challenges facing our society.
Floods in the Pyrenees: A global view through a regional database
(European Geosciences Union (EGU), 2024-10-07) Llasat Botija, María del Carmen; Llasat-Botija, Montserrat; Pardo, Erika; Marcos Matamoros, Raül; Lemus Cánovas, Marc
This paper shows the first systematic datasetof flood episodes referring to the entire Pyrenees massif,named PIRAGUA_flood, which covers the period 1981–2015 (available at http://hdl.handle.net/10261/270351, lastaccess: 21 July 2024). First, the structure of the database isdetailed so that it can be reproduced anywhere else in theworld, adapting to the specific nature of each situation. Subsequently,the paper addresses the spatial and temporal distributionof flood episodes and events (including trends) thataffected the Pyrenees regions of Spain (Catalonia, Aragon,Navarre, the Basque Country), France (Nouvelle-Aquitaine,Occitanie) and Andorra, as well as the massif as a whole,for a given period of time. In the case of the Spanish regions,it was also possible to analyse the compensation paymentsby the Spanish Insurance Compensation Consortiumand the number of deceased. The weather types associatedwith flood episodes were also classified based on sea levelpressure and 500 hPa geopotential height from ERA5. Theresults show 181 flood events and 154 fatalities, some ofwhich affected more than one region. In the Spanish part ofthe Pyrenees, between 1996 and 2015, there was a total compensationpayout amounting to EUR 142.5 million (2015).The eastern part of the area records more flood events thanthe western one, with Catalonia being the community thatregistered the highest number of events, followed by Andorraand Occitanie. Associated weather types are dominatedby the southern component flow over the Pyrenees region,with a talweg on the Iberian Peninsula and a depression inthe vicinity, either in the Atlantic or in the Mediterranean.In terms of the entire massif, there is a slight positive trendof 0.84 events per decade, driven by the evolution of ordinaryand extraordinary floods but not significant at 95 %. Ata regional level, flood behaviour is more heterogeneous, althoughnot significant for the most part. Nouvelle-Aquitaineis the only region that shows a positive and significant trendof 0.34 events per decade
Challenges for drought assessment in the Mediterranean region under future climate scenarios
(Elsevier B.V., 2020-11-01) Quintana-Segui, Pere; Renard, Delphine; Turco, Marco; Turkes, Murat; Trigo, Ricardo; Vidal, Jean-Philippe; Vilagrosa, Alberto; Zribi, Mehrez; Polcher, Jan; Cailleret, Maxime; Kalin, Ksenija Cindric; Davi, Hendrik; Dupuy, Jean-Luc; Greve, Peter; Grillakis, Manolis; Hanich, Lahoucine; Jarlan, Lionel; Martin-StPaul, Nicolas; Martinez-Vilalta, Jordi; Tramblay, Yves; Koutroulis, Aristeidis; Samaniego, Luis; Vicente-Serrano, Sergio M.; Volaire, Florence; Boone, Aaron; Le Page, Michel; Llasat Botija, María del Carmen; Albergel, Clement; Burak, Selmin; Mouillot, Florent; Pulido-Velazquez, David
Droughts can have strong environmental and socio-economic impacts in the Mediterranean region, in particular for countries relying on rain-fed agricultural production, but also in areas in which irrigation plays an important role and in which natural vegetation has been modified or is subject to water stress. The purpose of this review is to provide an assessment of the complexity of the drought phenomenon in the Mediterranean region and present various perspectives on drought in the present and under future climate change scenarios. The projections of various model experiments on future climate change scenarios strongly agree on an increased frequency and severity of droughts in the Mediterranean basin. Nevertheless, given the complexity of the phenomenon, with different types of droughts and complex interrelated impacts, significant future uncertainties remain. For example, uncertainties are stronger for hydrological droughts than meteorological droughts due to human influences and water withdrawal. Significant drought impacts are expected in the future, in particular for developing countries in the southern and eastern parts of the Mediterranean basin. To improve the resilience and adaptive capacities of societies and environments faced with drought, we aim to provide an overview of the key issues in research on climate change impacts on droughts, with a specific focus on the Mediterranean region, in order to: i) redefine more meaningful drought metrics tailored to the Mediterranean context, ii) better take into account vegetation and its feedback on droughts, iii) improve the modelling and forecasting of drought events through remote sensing and land surface models, and iv) promote a more integrated vision of droughts taking into account both water availability and water use. This overview reflects the complexity of the problem and the need to combine scientific research with adaptation solutions to deal with drought in the future.
Analysis of the behavior of highly focused, radially coherent Dirichlet sources
(Elsevier B.V., 2024-02-15) Martínez-Herrero, Rosario; Aviñoá, Marcos; Carnicer González, Arturo
We introduce a novel class of electromagnetic light sources that exhibit radial coherence, a degree of coherence characterized by a Dirichlet kernel, and with radial or azimuthal polarization. We provide a mathematical description of the spectral irradiance, 3D degree of polarization, and electromagnetic degree of coherence for such sources when they are focused using a high numerical aperture microscope lens. Since the incident beam can be described as a modal expansion, we also consider how the number of terms affects the behavior of the field in the focal area. The formal analysis is complemented with numerical simulations. The study reveals interesting properties in the focal area, despite the focused beam is no longer radially coherent.
Method for reducing specular reflections in Mueller matrix imaging
(Optical Society of America, 2025-05-12) Pardo, Iago; Bian, Subiao; Pascual Miralles, Esther; Arteaga Barriel, Oriol
Mueller matrix polarimetry has emerged as a powerful tool for non-destructiveoptical analysis of biological tissues and bioorganic materials, offering detailed insights intopolarization-specific properties such as diattenuation, retardance, and depolarization. However,the accurate application of Mueller matrix polarimetry in biological media is often hindered byspecular reflections, which obscure signals from deeper tissue layers and degrade the samplevisualization and the polarimetric data quality. Existing methods to minimize specular reflectionhave limitations, especially in clinical or in vivo settings where sample positioning is constrained.Here, we introduce a new approach for avoiding or reducing specular highlights without havingto reduce light intensity. By using near-cross-polarization states between the polarization stategenerator and analyzer, we demonstrate that one can obtain an enhanced visualization of tissuestructures, reduce the appearance of specular reflections, and maintain a good polarimetriccontrast.
QBOi El Niño-Southern Oscillation experiments: teleconnections of the QBO
(European Geosciences Union (EGU), 2025-11-17) Naoe, Hiroaki; García-Franco, Jorge Luis; Park, Chang Hyun; Rodrigo Sánchez, Mario; Palmeiro, Froila M.; Serva, Federico; Taguchi, Masakazu; Yoshida, Kohei; Anstey, James A.; García-Serrano, Javier, 1980-; Son, Seok Woo; Kawatani, Yoshio; Butchart, Neal; Hamilton, Kevin; Chen, Chih Chieh; Glanville, Anne; Kerzenmacher, Tobias; Lott, François; Orbe, Clara; Osprey, Scott; Park, Mijeong; Richter, Jadwiga H.; Versick, Stefan; Watanabe, Shingo
This study investigates Quasi-Biennial Oscillation (QBO) teleconnections and their modulation by the El Niño–Southern Oscillation (ENSO) using a multi-model ensemble from the Atmospheric Processes And their Role in Climate (APARC) QBO initiative (QBOi). Analyzing observed QBO–ENSO teleconnections is challenging because it is difficult to separate the respective influences of QBO and ENSO outside the QBO region due to aliasing in the historical record. To isolate these signals, simulations were conducted with annually repeating prescribed sea-surface temperatures (SSTs) representing idealized El Niño and La Niña conditions (the QBOi EN and LN experiments, respectively), and results are compared with the QBOi control experiment (CTL) under ENSO-neutral conditions. The strength of the Holton-Tan relationship between the phase of the QBO and the strength of the polar vortex seen in observations is reproduced in fewer than three models in CTL and by one model in EN. In LN, three out of nine models reproduce the observed Holton–Tan relationship, but with less than half of the observed amplitude. In the Arctic winter climate, sudden stratospheric warmings (SSWs) occur more frequently in EN than in LN; however, unlike in observations, there is no discernible difference in SSW frequency between QBO westerly (QBO-W) and QBO easterly (QBO-E) phases. The Asia-Pacific subtropical jet (APJ) shifts significantly equatorward during QBO-W compared to QBO-E in observations, but this shift is not robust across models, regardless of ENSO phases. In the tropics, the sign and spatial pattern of the QBO precipitation response vary widely across models and experiments, indicating that any potential QBO signal is strongly modulated by the prevailing ENSO phases. Overall, the QBOi models exhibit unrealistically weak QBO wind amplitudes in the lower stratosphere, which may explain the weak polar vortex and APJ responses, as well as the weak precipitation signals in the tropics. In contrast, the QBO teleconnection with the Walker circulation during boreal summer and autumn shows consistent signals in both observations and most models. Specifically, the QBO-W phase is characterized by upper-level westerly and lower-level easterly anomalies over the Indian Ocean–Maritime Continent relative to QBO-E, although the amplitude and timing of these anomalies remain model-dependent. Notably, the influence of QBO phase on the Walker circulation appears insensitive to the ENSO phase.
Mechanisms of the QBO influence on the tropical troposphere: climatological SST conditions
(Wiley, 2025-11-22) Rodrigo Sánchez, Mario; García-Franco, Jorge Luis; García-Serrano, Javier, 1980-; Bladé, Ileana; Palmeiro, Froila M.
The Quasi-Biennial Oscillation (QBO), the leading mode of tropical stratospheric variability, is thought to influence the tropical troposphere. Disentangling this influence from the dominant effects of El Niño-Southern Oscillation (ENSO) remains challenging. In this study, we use an atmosphere-only experiment with climatological sea surface temperature to isolate the tropospheric impact of the QBO, while a companion article examines how ENSO further affects this impact. The analysis focuses on the QBO modulation of temperature and zonal wind in the upper troposphere-lower stratosphere (UTLS) and the accompanying effects on static stability, wind shear and vorticity. Our results show that the QBO modifies deep tropical convection over the Maritime Continent region, and affects both the zonal Walker circulation and, more notably, the meridional Hadley circulation. These impacts are highly seasonal, with the strongest effects in summer and autumn. A zonal asymmetry in the vertical structure of the QBO signal and its influence on tropical circulation is identified, with anomalies descending into the upper troposphere over the Indo-Pacific region. Our results also suggest that the timing of this teleconnection is primarily associated with QBO-induced changes in static stability, which exhibit a strong correlation with precipitation and arrive first at the UTLS, followed by changes in wind shear and vorticity.
Improving lithium-ion battery performance through patterned growth of carbon nanotubes over vertically aligned silicon nanowires
(Elsevier, 2024-11-10) Farid, Ghulam; Amade Rovira, Roger; Ma, Yang; Ospina, Rogelio; Serafin, Jarosław; Chaitoglou, Stefanos; Majumdar, Shubhadeep; Poveda, Adrian; Bertrán Serra, Enric
The pursuit of high-performance electrode materials for rechargeable energy storage systems has intensified recently. In this study, we introduce a novel fabrication method that precisely covers as-grown carbon nanotubes (CNTs) atop vertically aligned silicon nanowires (SiNWs), resulting in a unique CNT@SiNW hybrid structure. This innovative approach seeks to maximize the surface area of CNTs, with the ultimate goal of significantly enhancing the cycling stability of anodes in lithium-ion (Li-ion) batteries. The resulting hybrid structure exhibits a notably higher BET (Brunauer-Emmett-Teller) surface area, quantified at 150 m2/g, surpassing the 101 m2/g surface area of CNTs on silicon (Si) wafers. Moreover, the CNT@SiNW hybrid structure exhibits a larger pore size equal to 2.34 nm, compared to the 1.87 nm pore size observed for CNTs on Si wafers. Electrochemical assessments reveal the superior lithium storage performance of the CNT@SiNW hybrid structure compared to as-prepared CNTs electrodes. These improved electrochemical properties are primarily attributed to the synergistic effects between the CNTs and SiNW arrays, as well as the increased surface area of CNTs grown on the SiNW tips. Overall, the findings of this study strongly advocate for the promising potential of the CNT@SiNW hybrid structure as anode materials for high-performance energy storage devices.
Enhancing hydrogen evolution: Carbon nanotubes as a scaffold for Mo2C deposition via magnetron sputtering and chemical vapor deposition
(Elsevier Ltd., 2024-11-04) Majumdar, Shubhadeep; Chaitoglou, Stefanos; Serafin, Jarosław; Farid, Ghulam; Ospina, Rogelio; Ma, Y.; Amade Rovira, Roger; Bertrán Serra, Enric
This study presents an innovative approach to fabricating carbon nanotubes (CNTs) through magnetron sputtering and chemical vapor deposition (CVD). These CNTs serve as a robust structural scaffold for the deposition of molybdenum, which, through thermal annealing, becomes molybdenum carbide (Mo2C), which is highly efficient for hydrogen evolution reaction (HER). Our investigation delves into the physical and chemical attributes of these electrodes, revealing insights into the functionality of Mo2C on CNTs hybrid structures. Chemical characterization confirms the exceptional performance of the electrode. Our Mo2C on CNT hybrid system showcases remarkable electrocatalytic activity, with an onset potential of 103 mV at 1 mA/cm2 and an overpotential of 176 mV at 10 mA/cm2. Further validation comes from tests revealing a Tafel slope of 95 mV/dec, affirming its superiority in facilitating HER. Unparalleled combination of low charge transfer resistance and accelerated reaction kinetics, Mo2C on CNTs hybrid structure is poised to significantly enhance HER activity.
Comprehensive analysis of MAX phase and MXene materials for advanced photocatalysis, electrocatalysis and adsorption in hydrogen evolution and storage
(Elsevier, 2024-12-01) Serafin, Jarosław; Dziejarski, Bartosz; Achieng, George Oindo; Vendrell, Xavier; Chaitoglou, Stefanos; Amade Rovira, Roger
Over the past twenty-five years, MAX phases and their derivatives, MXenes, have become a focal point in materials research. These compounds seamlessly blend ceramic and metallic properties, offering high thermal and electrical conductivity, mechanical strength, low density, and resistance to extreme conditions. Their versatility positions them as promising candidates for diverse applications, particularly in advanced photo-catalysis and electro-catalysis for hydrogen evolution. Furthermore, MAX phases and MXenes are potential hydrogen storage materials, with unique structures that provide ample space for efficient hydrogen gas storage and release, vital for clean energy technologies like fuel cells. This review aims to comprehensively analyze their roles in photo-catalysis, electro-catalysis, and hydrogen storage, with a focus on their layered crystal structure. MAX phases integrate superior metal and ceramic attributes, while MXenes offer tunable electronic structures that enhance catalytic performance. Continued exploration is crucial to unlock their full potential, advancing clean energy technologies and beyond.
Rapid amyloid-β clearance and cognitive recovery through multivalent modulation of blood–brain barrier transport
(Springer Nature, 2025-12-01) Gong, Qiyong; Tian, Xiaohe; Battaglia, Giuseppe; Chen, Junyang; Xiang, Pan; Duro-Castano, Aroa; Cai, Huawei; Guo, Bin; Liu, Xiqin; Yu, Yifan; Lui, Su; Luo, Kui; Ke, Bowen; Ruiz-Perez, Lorena
The blood‒brain barrier (BBB) is a highly selective permeability barrier that safeguards the central nervous system (CNS) from potentially harmful substances while regulating the transport of essential molecules. Its dysfunction is increasingly recognized as a pivotal factor in the pathogenesis of Alzheimer’s disease (AD), contributing to the accumulation of amyloid-β (Aβ) plaques. We present a novel therapeutic strategy that targets low-density lipoprotein receptor-related protein 1 (LRP1) on the BBB. Our design leverages the multivalent nature and precise size of LRP1-targeted polymersomes to modulate receptor-mediated transport, biasing LRP1 traf cking toward transcytosis and thereby upregulating its expression to promote ef cient Aβ removal. In AD model mice, this intervention signi cantly reduced brain Aβ levels by nearly 45% and increased plasma Aβ levels by 8-fold within 2 h, as measured by ELISA. Multiple imaging techniques con rmed the reduction in brain Aβ signals after treatment. Cognitive assessments revealed that treated AD mice exhibited signi cant improvements in spatial learning and memory, with performance levels comparable to those of wild-type mice. These cognitive bene ts persisted for up to 6 months post-treatment. This work pioneers a new paradigm in drug design, where function arises from the supramolecular nature of the nanomedicine, harnessing multivalency to elicit biological action at the membrane traf cking level. Our ndings also reaf rm the critical role of the BBB in AD pathogenesis and demonstrate that targeting the BBB can make therapeutic interventions signi cantly more effective. We establish a compelling case for BBB modulation and LRP1-mediated Aβ clearance as a transformative foundation for future AD therapies.
The minimal chemotactic cell
(American Association for the Advancement of Science, 2025-07-25) Battaglia, Giuseppe; Borges Fernandes, Barbara; Apriceno, Azzurra; Arango-Restrepo, Andrés; Almadhi, Safa; Ghosh, Subhadip; Forth, Joe; López-Alonso, Jorge Pedro; Ubarretxena-Belandia, Iban; Rubi, José Miguel; Ruiz-Perez, Lorena; Williams, Ian
The movement of cells and microorganisms in response to chemical gradients (chemotaxis) has played an essential role in the evolution of many biological processes. Cellular navigation works via the holistic assembly of numerous components into machineries that transform chemical energy into locomotion. Herein we present and discuss the minimal elements required for cell-like vesicles to be chemotactic. We show that lipid vesicles can propel themselves in response to chemical gradients when only a transmembrane protein and an encapsulated enzyme are incorporated into the vesicle structure. The herein proposed model serves as a proof of concept to show that even the simplest cell-like structure can experience chemotactic navigation.
Thermoplasmonic Polymersome Membranes by In Situ Synthesis
(American Chemical Society, 2025-04-18) Barbieri, Valentino; González Colsa, Javier; Matias, Diana; Duro-Castano, Aroa; Thapa, Anshu; Ruiz-Perez, Lorena; Albella, Pablo; Volpe, Giorgio; Battaglia, Giuseppe
Thermoplasmonic nanoparticles, known for releasing heat upon illumination, find diverse applications in catalysis, optics, and biomedicine. Incorporating plasmonic metals within organic vesicle membranes can lead to the formation of nanoreactors capable of regulating temperature-sensitive microscopic processes. Yet, the controlled formation of stable hybrid vesicles displaying significant thermoplasmonic properties remains challenging. This work presents the in situ synthesis of highly efficient thermoplasmonic polymer vesicles, or hybrid polymersomes, by nucleating ∼2 nm gold nanoparticles within preformed polymersome membranes. This process preserves the vesicles’ morphology, stability, and overall functionality. Despite the small size of the embedded plasmonic nanoparticles, these hybrid polymersomes can efficiently convert laser light into a notable temperature increase on a larger scale through collective heating. We develop a theoretical framework that rationalizes the structure–property relations of hybrid polymersomes and accurately predicts their collective thermoplasmonic response. Finally, we demonstrate the biomedical potential of our polymersomes by employing their photothermal properties to induce the hyperthermal death of cancer cells in vitro, an effect amplified by their superior cellular uptake. We envision that these hybrid polymersomes will evolve into a versatile platform for precise control over nanoscale chemical and biological processes through plasmonic heating, unlocking numerous opportunities across various scientific and medical contexts.
Meteorological factors and incidence of COVID-19 during the FIRST wave of the pandemic in Catalonia (Spain): A multi-county study
(Elsevier B.V., 2021-03-29) Tobias, Aurelio; Molina, Tomàs, 1963-; Rodrigo Sánchez, Mario; Saez, Marc
The transmission of coronaviruses can be affected by several factors, including the climate. Due to the rapid spread of COVID-19 and the urgent need for rapid responses to contain the pandemic, it is essential to understand the role that weather conditions on the transmission of SARS-CoV-2. We evaluate the influence of meteorological factors on the incidence of COVID-19 during the first wave of the epidemic in Catalonia. We conducted a geographical analysis at the county level to evaluate the association between mean temperature, absolute humidity, solar radiation, and the cumulative incidence of COVID-19. Next, we used a time-series design to assess the short-term effects of meteorological factors on the daily incidence of COVID-19. We found a geographical association between meteorological factors and the cumulative incidence of COVID-19, from the end of March to June 2020, and a lesser extent in the short-term on the daily incidence during the first wave of the epidemic in Spain. Our findings suggest that warm and wet climates may reduce the incidence of COVID-19 in Catalonia. However, policy makers must interpret with caution any COVID-19 risk predictions based on climate information alone.

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