Resultados de investigación

Strong coupling between light and molecular matter is currently attracting interest both in chemistry and physics, in the fast-growing field of molecular polaritonics. The large near-field enhancement of the electric field of plasmonic surfaces and their high tunability make arrays of metallic nanoparticles an interesting platform to achieve and control strong coupling. Two dimensional plasmonic arrays with several nanoparticles per unit cell and crystalline symmetries can host topological edge and corner states. Here we explore the coupling of molecular materials to these edge states using a coupled-dipole framework including long-range interactions. We study both the weak and strong coupling regimes and demonstrate that coupling to topological edge states can be employed to enhance highly-directional long-range energy transfer between molecules., We.acknowledge financial support from the grants BICPLAN6G (TED2021-131417B-I00) and LIGHTCOMPAS (PID2022-137569NB-C41), funded by MCIU/AEI/10.13039/501100011033, “ERDF A way of making Europe”, and European Union NextGenerationEU/PRTR and from MCIU through predoctoral fellowship PRE2019-090689., Peer reviewed

Description of the project: The reference fire perimeters for Madagascar were obtained in the framework of the project "Fire regimes and ecosystem services in African biodiversity hotspots: can fire policies favoring climate change mitigation, biodiversity and local communities converge?" financed by the Swiss Network for International Studies (SNIS). Among the goals of the project is the accurate characterization of burned area and fire regimes at Sentinel-2 spatial resolution (20m). The burned area database has been produced for the period 2016-2022 in Madagascar, southern Mozambique, Eswatini and Eastern South Africa (Fernández-García et al., 2023: https://doi.org/10.5281/zenodo.8201841). The MGBAS2 reference data presented here is the validation data for the mentioned burned area database. The characterization of burned area is the first step of the project that also aims to analyze the drivers of fire regimes and their consequences on carbon dynamics, biodiversity and local livelihoods., This file contains four folders: - metadata: includes a .csv file for each year (2019 and 2021) containing the file name of all the reference files included in the dataset and their associated information and a read.txt file with a description of the fields in the csv file. - regions: includes a shapefile for each year (2019 and 2021) containing all the sample sites covered by the dataset. - sampling: includes a shapefile with the fraction of burned land in 2021 according to the MGBAS2 burned area database (0= low burned area 1=high burned area). - shapefiles: includes the validation reference shapefiles for each year (2019 and 2021)., The MGBAS2 reference data was derived from Sentinel-2 images over a set of 6 tiles (sampling units)sampled following a design customized for the Sentinel tiling grid system and to represent low and high burned area occurrence strata in Madagascar. Over each tile Sentinel-2 time series were defined based on a set of conditions for minimizing cloud cover and to guarantee series length and a minimum time lag between image pairs. Sentinel-2 image pairs were classified with a Random Forest (RF) algorithm to provide burned perimeters of depicting areas that burned between the two dates that were combined in a synthetic burned area reference dataset. This dataset represent for each unit burned and unburned polygons and masked areas. A detailed description of the dataset can be found in Fernández-García et al.(2023) ("Madagascar’s burned area from Sentinel-2 imagery (2016–2022): four times higher than from lower resolution sensors", in preparation)., This research has been funded by the project "Fire regimes and ecosystem services in African biodiversity hotspots: can fire policies favoring climate change mitigation, biodiversity and local communities converge" financed by the Swiss Network for International Studies (SNIS)., Peer reviewed

Persistent luminescence (PersL) materials have applications in diverse fields such as smart signaling, anticounterfeiting, and in vivo imaging. However, the lack of a thorough understanding of the precise mechanisms that govern PersL makes it difficult to develop ways to optimize it. Here we present an accurate model to describe the various processes that determine PersL in ZnGa2O4:Cr3+ (ZGO:Cr), a workhorse material in the field. A set of rate equations has been solved, and a global fit to both charge/discharge and thermoluminescence measurements has been performed. Our results establish a direct link between trap depth distribution and afterglow kinetics and shed light on the main challenges associated with PersL in ZGO:Cr nanoparticles, identifying low trapping probability and optical detrapping as the main factors limiting the performance of ZGO:Cr, with a large margin for improvement. Our results highlight the importance of accurate modeling for the design of future afterglow materials and devices., This project has received funding from the BBVA Foundation Leonardo Grant for Physics Researchers 2023, and from MCIN/AEI/10.13039/501100011033 by European Union NextGeneration EU/PRTR under grant EUR2023-143467., - fig_2_a.txt : PL spectra (normalized to the R line) measured at 80K: Wavelength in nm (column 1), PL for 420 nm excitation (column 2), PL for 330 nm excitation (column 3) - fig_2_b.txt : PersL spectra (normalized to maximum): Wavelength in nm (column 1), PersL (column 2) - fig_2_c.txt : PL decay measured at 80 K: Time in s (column 1), counts for 420 nm excitation (column 2), fit for 420 nm excitation (column 3), residuals for 420 nm excitation (column 4), counts for 330 nm excitation (column 5), fit for 330 nm excitation (column 6), residuals for 330 nm excitation (column 7). - fig_3_a.txt : Charge/discharge curves: Time in s (column 1), measured intensity for maximum,medium and minimum excitation power (columns 2-4), fitted intensity for maximum,medium and minimum excitation power (columns 5-7). - fig_3_b_1.txt : Thermoluminescence charging at RT: Temperature in K (column 1), measured intensity (column 2), fitted intensity (column 3). - fig_3_b_2.txt : Thermoluminescence charging at 15 K: Temperature in K (column 1), measured intensity (column 2), fitted intensity (column 3). - fig_3_c.txt : Trap depth distribution (normalized to maximum): Trap depth in eV (column 1), rho(Et) (column 2). - fig_4_a_1.txt : Normalized charged traps density (columns colunms correspond to trap depth while rows correspond to time after charging). - fig_4_a_2.txt : Time axis of fig_4_a_1.txt in s - fig_4_a_3.txt : Trap depth axis of fig_4_a_1.txt in eV - fig_4_b.txt : PersL as a function of trap depth and time after excitation: Trap depth in eV (column 1), PersL after t1= 0 s, 1 s, 30 s, 60 s, and 300 s (columns 2-6). - fig_5_1.txt : PersL as a function of delta_E1 and delta_Et . Rows correspond to delta_E1 while columns correspond to delta_Et. - fig_5_2.txt : delta_E1 axis of fig_5_1.txt in eV - fig_5_3.txt : delta_Et axis of fig_5_1.txt in eV, Peer reviewed

Additional description for fabrication procedures and supplemental data, including SEM images, Nyquist plots, thermal analyses, stress–strain curves, activation energies, as referenced in the text., Peer reviewed

Experimental data and TEM images from the nanoparticle synthesis, and data from catalytic characterization., Peer reviewed

[Introduction]: Secreted mucins are highly O-glycosylated glycoproteins produced by goblet cells in mucosal epithelia. They constitute the protective viscous gel layer overlying the epithelia and are involved in pathogen recognition, adhesion and expulsion. The gill polyopisthocotylidan ectoparasite Sparicotyle chrysophrii, feeds on gilthead seabream (Sparus aurata) blood eliciting severe anemia., [Methods]: Control unexposed and recipient (R) gill samples of gilthead seabream experimentally infected with S. chrysophrii were obtained at six consecutive times (0, 11, 20, 32, 41, and 61 days post-exposure (dpe)). In histological samples, goblet cell numbers and their intensity of lectin labelling was registered. Expression of nine mucin genes (muc2, muc2a, muc2b, muc5a/c, muc4, muc13, muc18, muc19, imuc) and three regulatory factors involved in goblet cell differentiation (hes1, elf3, agr2) was studied by qPCR. In addition, differential expression of glycosyltransferases and glycosidases was analyzed in silico from previously obtained RNAseq datasets of S. chrysophrii-infected gilthead seabream gills with two different infection intensities., [Results and Discussion]: Increased goblet cell differentiation (up-regulated elf3 and agr2) leading to neutral goblet cell hyperplasia on gill lamellae of R fish gills was found from 32 dpe on, when adult parasite stages were first detected. At this time point, acute increased expression of both secreted (muc2a, muc2b, muc5a/c) and membrane-bound mucins (imuc, muc4, muc18) occurred in R gills. Mucins did not acidify during the course of infection, but their glycosylation pattern varied towards more complex glycoconjugates with sialylated, fucosylated and branched structures, according to lectin labelling and the shift of glycosyltransferase expression patterns. Gilthead seabream gill mucosal response against S. chrysophrii involved neutral mucus hypersecretion, which could contribute to worm expulsion and facilitate gas exchange to counterbalance parasite-induced hypoxia. Stress induced by the sparicotylosis condition seems to lead to changes in glycosylation characteristic of more structurally complex mucins., Peer reviewed

Optimization of heating time in batch synthesis (Figure S1); physical and geometrical parameters adopted for Comsol Multiphysics simulation (Table S1); N2 adsorption analysis (Table S2); reproducibility analysis (Figure S2); TEM and HRSTEM characterization of SBA-15, unsupported Ag NCs, and Ag NCs/SBA-15 with 0.16, 0.62, and 0.96 wt % (Figure S3); leaching test for propargylguanidine cyclization (Figure S4, Table S3, and Figure S5); catalytic reusability and stability study by reaction of 2-(phenylethynyl)phenol (Figure S6); continuous flow reaction and activation energy for 2-(phenylethynyl)phenol cyclization (figure S7); reaction mechanism for hydroamination of propargylguanidines (Scheme S1); general procedure for the synthesis of starting material with corresponding characterization data., Peer reviewed

Crystallographic structure of [Au25(Cys)18], intensity distribution and emission wavelength of white light, time-resolved 1O2 phosphorescence decay of treated silicones, stability test of treated silicones, and comparison of photobactericidal enhancement by [Au25(Cys)18] nanoclusters synthesized through two different synthetic methods., Peer reviewed

Peer reviewed

Figure S1: Langmuir balance studies of Aβ42 interaction with membrane lipids. Representative time courses of the change in surface pressure of a lipid monolayer, at the air-water interface, upon addition of Aβ42 monomers into the subphase. Aβ42 stock solution was 50 μM. Aβ42 final concentration in the trough was 1.22 μM. T = 22 °C. Monolayer compositions and state of aggregation of Aβ are given on top of each plot., Peer reviewed