ISGlobal - Institut de Salut Global de Barcelona

Reconstructing the Holocene volcanic past of El Hierro, Canary Islands

Tue, 14 Apr 2026 10:17:35 GMT

Reconstructing the Holocene volcanic past of El Hierro, Canary Islands Prieto-Torrell, Claudia; Fernandez-Turiel, Jose-Luis; Rodriguez-Gonzalez, Alejandro; Aulinas Juncà, Meritxell; Beamud Amorós, Elisabet; Cabrera, M.C.; Criado, C.; Guillou, H.; Vidal-Matutano, P.; Perez-Torrado, Francisco Jose We present a geochronologic study with unprecedented detail from 42 Holocene subaerial volcanic edifices of El Hierro Island, Canary Islands. The study of new and published K-Ar, ⁴⁰Ar/³⁹Ar, ¹⁴C, and paleomagnetic ages, constrained by stratigraphic, geomorphic, and anthracological criteria, significantly improves the geochronologic framework of the Holocene volcanism at El Hierro. Our combined experiments show that radiocarbon and paleomagnetic dating were the best methods to determine this young volcanism’s age. Indeed, small amounts of ⁴⁰Ar* detected in most dated samples do not allow for calculating geologically significant ages. The preliminary anthracological study of charcoals is recommended before ¹⁴C dating. Thirty-six eruptive events (86 % of the total) were retained for the geochronological model developed with ChronoModel combining radiocarbon and paleomagnetic and using the Bayesian inference. Seventeen eruptions were dated for the first time. The Holocene eruptive activity at El Hierro exhibits significant variability over time, with recurrence intervals ranging from 34 to 1078 years. The most recent subaerial eruptions were Lomo Negro, 1412 [1560, 1242] cal BP (MAP, mode of the posterior distribution, and 95 % highest posterior density (HPD) interval) and Montaña del Tesoro, 1059 [1206, 967] cal BP. In addition, historical records suggest possible submarine eruptions in 1721, 1777, and 1793, as well as the more recent and well-documented Tagoro volcano submarine eruption (2011–2012 CE). This recent low recurrence subaerial volcanic activity is unusual for an oceanic volcanic island in the juvenile shield growth stage. The volcanic edifices resulted from hybrid Strombolian monogenetic eruptions with alternating or simultaneous emission of pyroclastic tephra and lava flows. The absence of lava flows in the eruptions of the highest part of the island’s summit is worth noting. This volcanic activity focused on the three rifts that configure the tetrahedral shape of the island, although the NW rift concentrated 50 % of the eruptions. These results contextualize the volcanic hazard of El Hierro in the face of eventual future eruptions.

Understanding and enhancing post-stroke recovery: Insights from a nested qualitative study within the MindFit Project randomized clinical trial

Tue, 14 Apr 2026 16:58:16 GMT

Understanding and enhancing post-stroke recovery: Insights from a nested qualitative study within the MindFit Project randomized clinical trial Bermudo-Gallaguet, Adrià; Bielsa-Pascual, Jofre; García-Sierra, Rosa; Feijoo Cid, Maria; Arreciado Marañón, Antonia; Ariza González, Mar; Agudelo, Daniela; Camins-Vila, Neus; Boldó, Maria; Durà Mata, Maria José; García-Molina, Alberto; Torán Monserrat, Pere; Mataró Serrat, Maria Background: Stroke survivors experience a wide range of physical, cognitive, and emotional challenges. In the MindFit Project, a randomized clinical trial, 141 chronic stroke patients were divided into three groups: mindfulness-based stress reduction (MBSR) with computerized cognitive training (CCT), physical exercise (PE) with CCT, and CCT alone. The interventions were conducted remotely over 12 weeks, including online group and individual sessions. Objective: This exploratory nested qualitative study aimed to investigate chronic stroke survivors' experiences, opinions, and perceived changes due to the interventions within the MindFit Project. The secondary objective was to describe the broader experience of their recovery journey. Methods: Twenty-seven participants were recruited through purposive sampling and engaged in semi-structured one-on-one interviews. Twelve received MBSR+CCT, nine received PE+CCT, and six received CCT-only. The interviews were recorded, transcribed, and analyzed using thematic analysis. Results: Participants shared insights into their lives after stroke, including emotional and physical challenges, coping mechanisms, and the impact of societal perceptions. The interventions were generally positively valued, with MBSR aiding in emotional regulation, PE enhancing physical capabilities, and CCT improving cognition. The group setting provided valuable peer support and motivation, although some participants noted challenges owing to the heterogeneity. The telematic format was also appreciated for its accessibility, although it posed challenges to personal interaction and intervention supervision. Conclusions: Our study emphasizes the complexity of stroke recovery and the importance of holistic, patient-centered rehabilitation approaches. It also highlights the value of combining physical and non-physical interventions in a group setting, along with the potential of remote platforms to enhance the accessibility of rehabilitation programs. These findings generate hypotheses for future randomized clinical trials aimed at improving post-stroke recovery.

Lava deltas, a key landform in oceanic volcanic islands: El Hierro, Canary Islands

Tue, 14 Apr 2026 09:41:31 GMT

Lava deltas, a key landform in oceanic volcanic islands: El Hierro, Canary Islands Rodriguez-Gonzalez, Alejandro; Fernandez-Turiel, Jose-Luis; Aulinas Juncà, Meritxell; Cabrera, M.C.; Prieto-Torrell, Claudia; Rodriguez, G.A.; Guillou, H.; Perez-Torrado, Francisco Jose Marine and subaerial erosion of volcanic ocean islands form coastal cliffs and shore platforms, particularly during stable sea levels. Posterosional lava flows can spill over these coastal cliffs and fill the platforms, leading to the progradation of lava deltas. This work aims to analyze this volcanic rocky coast setting at the island scale and to assess the volcanic constructional and erosive degradational effects on the coast at the scale of one volcanic edifice. El Hierro Island, Canary Islands, exemplifies a rocky coast with an active sea-cliff profile, reflecting its early evolutionary stage as a young ocean volcanic island with no fringing reef. The occurrence of a contemporary insular shelf formed during the Holocene sea-level highstand (<7 ka) allows constraining the ages of those eruptions forming lava deltas affecting this geomorphological landform. A detailed bathymetry around the island allowed us to distinguish 17 eruptions fulfilling this criterion. The Montaña del Tesoro, which occurred about 1050 years BP, is one of these eruptions and was selected as a case study for morphometric modeling integrating subaerial and submarine data at the scale of a volcanic edifice. This eruption was a Strombolian basaltic volcanic event that produced a scoria cone, pyroclastic fall deposits, and lava flows that reached the ocean in the eastern rift zone of El Hierro island. We combine field-based observations with topographic and bathymetric data analysis to reconstruct the pre- and post-eruption Digital Elevation Models (DEMs) and, comparing with present-day DEM, to analyze morphometrically the influence of volcanism on the coastal landscape's development. The resulting landform complexity required the discretization of the lava field according to the coastline evolution and lava front sectors, and the subaerial or submarine lava placement. The pyroclastic materials' total erupted bulk volume (12,829,578 m³) corresponds to a volcanic eruption index (VEI) of 3. This event was primarily effusive. From a dense rock equivalent (DRE) volume of 25,615,424 m³, 87 % flowed as lava, 10 % formed the cinder cone, and 3 % the tephra fall deposits. We quantitatively demonstrate that dominant degradation occurs in the lava field, mainly disturbed by marine erosion. Marine erosion removed 9 % of the erupted volume of lava flows against 1 % by fluvial erosion. This work provides methods and results of great interest with different implications in oceanic volcanic islands, among which we can mention coastal planning (e.g., rock coast evolution) and volcanic risk assessment (e.g., the importance of Holocene sea-level rise on the development of shore platforms facilitating the progradation of lava deltas).

Targeted Covalent Photoswitch for Two-Photon Control of Endogenous Receptors

Tue, 14 Apr 2026 12:45:37 GMT

Targeted Covalent Photoswitch for Two-Photon Control of Endogenous Receptors Santini, Ramona; Malieieva, Galyna; Sortino, Rosalba; Pons Allés, Santiago; Ramos Guerra, Cristian; Matera, Carlo; Gorostiza Langa, Pau The study of intact cells and their signaling circuits with light requires a stimulation strategy that is focused, deeply penetrating, and does not damage them. Implanted optic fibers, light-emitting diodes, and luminescent materials operated externally with tissue-penetrating infrared (IR) light are invasive or limited by light attenuation around the illumination point. To overcome these barriers, two-photon pharmacology takes advantage of femtosecond-pulsed IR laser light to produce deep and spatiotemporally precise cellular stimulation using specially designed photoswitchable drugs. Compounds that can be covalently tethered to the target neuroreceptor perform particularly well. However, the tethered photoswitches reported to date require mutagenesis of the target protein, which prevents the use of photopharmacology to stimulate the nervous system in wild-type animals. Here, we report the first two-photon optimized targeted covalent photoswitch (TCP2P) that combines the efficient two-photon isomerization of ortho-fluoro-substituted azobenzene with the ability to conjugate to nucleophilic residues of endogenous proteins (AMPA and kainate ionotropic glutamate receptors in neurons). TCP2P is readily obtained by click coupling of two precursor compounds prior to use, and after simple incubation, it enables controlling neuronal activity at one- and two-photon excitation up to 800 nm without genetic modifications.