Física Aplicada

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Synthesising a Fixed-Length Equispaced Linear Array to Produce Dolph–Chebyshev Patterns with Deep Nulls, a Desired Side Lobe Level and Different Beamwidths
(MDPI, 2025-03-01) Otero Gómez, Ibai; López Martín, María Elena; Rodríguez González, Juan Antonio; Ares Pena, Francisco José; Universidade de Santiago de Compostela. Departamento de Ciencias Morfolóxicas; Universidade de Santiago de Compostela. Departamento de Física Aplicada
A method for the synthesis of equally spaced antenna arrays based on the extension of the Orchard–Elliott–Stern technique to radiation patterns with three roots on the negative real axis of the Shelkunoff unit circle is presented. One of these roots is placed on the unit circle and the other two are off the unit circle with coordinates r and (Formula presented.). For a desired side lobe level (SLL), the synthesis of patterns with these roots allows for a multiplicity of solutions with different amplitude ratios, obtained by varying the value of r, each of which presents radiation patterns with different beamwidths and directivity, but with two fewer side lobes than the patterns obtained without these restrictions in the roots. The technique has been thoroughly applied to Dolph–Chebyshev patterns of 10, 18 and 40 elements, with a (Formula presented.) spacing and an SLL that guarantees maximum directivity in both cases. This approach ensures the study of examples of all sizes, from small to large. The findings derived from this technique would be applicable in the domain of wireless communications, where the necessity arises for radiation patterns that exhibit low SLL and adaptive beamwidth.
Dose-Dependent Effects of Atropine on Accommodative and Binocular Visual Function for Myopia Control in Children: A Systematic Review and Meta-Analysis
(Springer, 2026-05-18) Martínez Pérez, Clara; Santodomingo Rubido, Jacinto; Villa Collar, César; Universidade de Santiago de Compostela. Departamento de Física Aplicada
PURPOSE: To evaluate systematically the effect of different concentrations of atropine eye drops on accommodative amplitude and binocular visual function in children and adolescents with myopia. METHODS: A systematic review and meta-analysis of randomised controlled trials was conducted in accordance with PRISMA 2020 guidelines and registered in PROSPERO (registration number: CRD420261297760). PubMed, Web of Science and Scopus were searched up to January 15, 2025. Eligible studies compared atropine eye drops (0.01–1%) with placebo, single-vision correction or no treatment and reported accommodative or binocular vision outcomes. The primary outcome was the change in accommodative amplitude. Secondary outcomes included accommodative lag, stereoacuity, heterophoria and fusional vergence. Mean differences (MD) with 95% confidence intervals (CI) were pooled using fixed- or random-effects models based on heterogeneity. RESULTS: Thirteen randomised controlled trials were included, most of which were conducted in Asian populations. Low-dose atropine (0.01%) was associated with a small but statistically significant reduction in accommodative amplitude (MD: −0.84 D, 95% CI: −1.50 to −0.18), with substantial heterogeneity and no consistent effects at individual follow-up time points. Intermediate concentrations (0.02–0.03%) showed variable and heterogeneous effects. Atropine 0.05% produced a consistent and clinically meaningful reduction in accommodative amplitude (MD: −1.96D, 95% CI: −2.36 to −1.57) and measurable changes in binocular parameters. Higher concentrations (≥0.1%) resulted in marked cycloplegic effects. CONCLUSIONS: The effects of atropine on accommodation and binocular visual function are dose-dependent. Low-dose atropine demonstrates a favourable functional safety profile, while higher concentrations are associated with clinically relevant accommodative impairment.
In Vitro Structural and Functional Studies of a Novel Cupredoxin, FtrB, from Brucella abortus 2308
(American Chemical Society, 2025-03-22) Kerkan, Alexa; Santisteban Veiga, Andrea; Banerjee, Sambuddha; Universidade de Santiago de Compostela. Departamento de Física Aplicada; Universidade de Santiago de Compostela. Instituto de Materiais (iMATUS)
FtrABCD is a four-component iron transporter found in several Gram-negative bacteria. Previous data confirm that FtrABCD can only utilize Fe2+ and the inner membrane permease, FtrC, from this system, like its eukaryotic homologue, Ftr1p, is predicted to utilize the free energy released during Fe2+ oxidation for the transport. Periplasmic FtrB from this system is coancestral with known copper oxidases, and the conserved D118 and H121 are predicted to bind to Cu2+, forming an active enzyme. In this work, we report structural data for recombinant wild-type and D118A and H121A mutants from Brucella abortus 2308 which confirm a β-sheet-rich structure which is distinct from known cupredoxins. Calorimetric studies on the wild-type protein show μM affinities for Cu2+ and an Fe2+ mimic (Mn2+), which facilitate the formation of the active enzyme and the enzyme-substrate complex, respectively. In contrast, the D118A mutant failed to bind Cu2+. Finally, the electrochemical data reported here revealed biologically accessible reduction potentials for the Cu2+ ion in the active enzyme which also showed a pseudozero-order rate of Fe2+ oxidation at pH 6.5 and could oxidize Fe2+ 3.5-times faster than its rate of autoxidation. Taken together, this report provides experimental data that support structural and functional predictions of FtrB under in vitro conditions.
Comparison of monofocal and multifocal contact lenses on binocular distance optical performance in non-presbyopic participants
(Springer, 2026-04-28) Castro Giráldez, Alba; Díaz Pombo, Antón; García Queiruga, Jacobo; Pena Verdeal, Hugo; Giráldez Fernández, María Jesús; Yebra-Pimentel Vilar, Eva; Universidade de Santiago de Compostela. Facultade de Óptica e Optometría; Universidade de Santiago de Compostela. Departamento de Física Aplicada
Purpose To compare binocular distance optical performance in non-presbyopic optometry students under different contact lens conditions: no lenses, monofocal lenses, and multifocal lenses. Methods A total of 20 optometry students (age: 23.00 ± 2.58 years) meeting eligibility criteria were recruited. The study employed a randomized crossover design with two sessions: (1) baseline without contact lenses (W-CL), and (2) experimental where each participant was fitted with monofocal contact lenses (M-CL; Clariti 1‑Day) and multifocal contact lenses (MF-CL; Clariti 1‑Day Multifocal) in random order, using the permutation method balanced 1:1 across participants within the same session. Optical performance was assessed by measuring binocular distance visual acuity parameters (corrected distance visual acuity [CDVA] and dynamic visual acuity [DVA]) and binocular depth perception parameters (fixation disparity and stereopsis), using the OptoTab POLAR 24″ SMT4V device under standardized conditions. Results Significant differences in visual acuity parameters (CDVA and DVA) were found across conditions (repeated measures ANOVA, p < 0.001), with post hoc analysis showing reduced acuity for MF-CL vs. W‑CL and M‑CL (Sidak, all p ≤ 0.002). For both parameters, effect sizes were negligible between W‑CL and M‑CL (all Cohen’s d = 0.07–0.09), and small and clinically meaningful when MF-CL was involved (all Cohen’s d = 0.08–0.17). No significant differences in depth perception parameters (fixation disparity or stereopsis) were found across conditions (all p ≥ 0.103) with negligible to small effect sizes (Cohen’s d, all p ≥ 0.38). Conclusion In non-presbyopic participants, MF-CL significantly reduced visual acuity parameters compared to M‑CL and W‑CL, but not optical performance related to binocular vision.
Intraocular pressure fluctuations assessment in professional wind instrument players
(Taylor & Francis, 2024-01-09) Noya Padín, Verónica; Pena Verdeal, Hugo; Nores Palmas, Noelia; Giráldez Fernández, María Jesús; Yebra-Pimentel Vilar, Eva; Universidade de Santiago de Compostela. Departamento de Física Aplicada
Clinical relevance: Due to the long-time that wind musicians spend playing their instruments, it is important to investigate if intraocular pressure could be affected by this activity. Background: To assess the intraocular pressure fluctuations and fluctuations affecting factors in professional wind musicians while playing different tones. Methods: Thirty professional wind musicians (23.0 ± 3.20 years) were recruited from the Professional Music College of A Coruña. A questionnaire about environmental/demographic factors was given to participants. Intraocular pressure was measured four times by ICare IC100 tonometer: before, during low and high-pitched tones, and immediately after stopping playing the wind instrument. Results: Pairwise comparison revealed statistical differences between measurement points (Sidak, all p ≤ 0.019), except between before playing and while playing low-pitched tones (Sidak, p = 1.000). Intraocular pressure increases during high pitch playing and decreases after stopping playing. No significant differences in intraocular pressure fluctuation were reported between physically active (>2 days/week) and non-physically active participants (Unpaired t-test, p = 0.680). All intraocular pressure values were positively correlated (Pearson's correlation, all r ≥ 0.505, p ≤ 0.004). Intraocular pressure fluctuations were negatively correlated with musical playing years (Pearson's correlation, r = - 0.396, p = 0.030). There were no significant correlations among intraocular pressure fluctuation and gender, age, weight, height, or daily time playing (Pearson's correlation, all p ≥ 0.058). Conclusion: Professional wind musicians suffer intraocular pressure peaks while playing high-pitched tones; therefore, ocular fundus evaluation and visual campimetry should be performed as routine tests in the visual exam of this population.
Intraocular pressure fluctuations and the role of the Valsalva maneuver in young professional musicians
(Elsevier, 2026-04-22) Noya Padín, Verónica; Silva, Filipe da; Martingo, Ângelo; Matos, Vítor; Lira, Madalena; Pena Verdeal, Hugo; Universidade de Santiago de Compostela. Departamento de Física Aplicada
Objective (1) To determine whether intraocular pressure (IOP) fluctuations while playing musical instruments is specific to the instrument type, (2) to investigate the role of the Valsalva maneuver as an underlying mechanism, and (3) to evaluate relationships between IOP values and demographic and environmental factors. Design Cross-sectional study. Participants Sixty-five musicians were enrolled. Of these, 2 were excluded due to glaucoma history and intolerance to IOP measurements. The final sample consisted of 63 young professional musicians (34 wind instrumentalists and 29 non-wind instrumentalists). Methods Participants underwent tonometry (ICare IC100) and otoscopy (Dino-Lite Basic EarScope) and completed a self-administered questionnaire on demographic and environmental factors. Tonometry and otoscopy procedures were performed simultaneously at four time point: before playing, while playing a low-pitched note and a high-pitched note, and after playing. Main outcome measures IOP and tympanic membrane movement. Results No differences in IOP were observed between wind and non-wind instrumentalists at baseline, during low-pitch playing, or after playing (Mann-Whitney U test, all p≥0.052). However, IOP differed while high-pitch playing (Mann-Whitney U test, p=0.007), with both high- and low-resistance wind instrumentalists showing higher IOP than non-wind instrumentalists (Mann-Whitney U test, both p≤0.041). IOP change relative to baseline (ΔIOP) similarly revealed differences during high-pitch playing and additionally detected differences during low-pitch playing (Mann-Whitney U test, both p≤0.025). Within the wind category, no differences in IOP were found between high- and low-resistance (Mann-Whitney U test, all p≥0.323), and same pattern was observed for ΔIOP (Mann-Whitney U test, all p≥0.112). The Valsalva maneuver was not detected for any instrument or under any measurement conditions. In addition, no relationships were found with demographic or environmental factors and IOP fluctuations (Pearson’s or Spearman’s correlation, all p≥0.273), although baseline IOP positively correlated with age at which wind instrumentalists began playing their instrument (Pearson’s correlation, r=0.348, p=0.048). Conclusions IOP fluctuations during musical instrument performance occur specifically in wind instrumentalists and are not attributable to involuntary Valsalva maneuvers during playing. Moreover, basal IOP correlated with age of instrument debut in wind instrumentalists, while no other demographic or environmental factors related to IOP measurements or its fluctuations.
Effects of HP-Guar Nano-emulsion Artificial Tears on Symptoms and Severity of Meibomian Gland Dysfunction in Evaporative Dry Eye During a 90-Day Longitudinal Study
(Springer, 2026-04-27) Pena Verdeal, Hugo; García Queiruga, Jacobo; Castro Giráldez, Alba; Sabucedo Villamarín, Belén; García Resúa, Carlos; Giráldez Fernández, María Jesús; Yebra-Pimentel Vilar, Eva; Universidade de Santiago de Compostela. Facultade de Óptica e Optometría; Universidade de Santiago de Compostela. Departamento de Física Aplicada
Background: To evaluate whether hydroxypropyl-guar (HP-Guar) nano-emulsion artificial tears improve symptoms, quality of life, severity of meibomian gland dysfunction (MGD) and evaporative dry eye (EDE)-related parameters in mild-to-moderate EDE participants over 90 days. Methods: Fifty-one mild-to-moderate EDE participants were recruited for a single-masked, longitudinal clinical trial without a control group or placebo. Inclusion criteria comprised: Ocular Surface Disease Index (OSDI) between 13–32 points; at least one positive diagnostic sign (Non-Invasive Tear Break-Up Time [NIBUT] <10 s and/or corneal staining >1) and two classification signs (Tear Meniscus Height [TMH] ≥0.20 and ≤0.50 mm and MGD score ≥5 points). Participants applied 1–2 drops of HP-Guar nano-emulsion artificial tears per eye, four times daily for 90 days, with follow-up assessments at baseline, 30, 60 and 90 days. Three groups of tests were conducted each session: DED symptomatology and quality of life (OSDI, EuroQol 5-Dimension 5-Level [EQ-5D-5L]), MGD severity (MGD score, meibomian gland loss area [MGLA]) and EDE-related parameters (meibomian gland expression [MGE], Meibometry, lipid layer pattern (LLP), NIBUT, ocular redness and corneal staining). Results: Significant differences in OSDI score, EQ-5D-5L in the ‘Healthy today’ scale, MGD score, lower eyelid MGLA and LLP were observed across sessions (all p ≤ 0.03). However, no significant differences were found in EQ-5D-5L score, upper eyelid MGLA, MGE, Meibometry, NIBUT-first, NIBUT-average, limbal or bulbar redness in any area or corneal staining (all p ≥ 0.09). Conclusions: This 90‑day single‑masked study without a control group found that HP‑Guar nano‑emulsion eye drops were associated with improvements in symptoms, perceived health and MGD‑related signs. These findings are exploratory and require confirmation in controlled trials.
A fast and automated approach for urban CFD simulations: validation with meteorological predictions and its application to drone flights
(Elsevier, 2025-12) Suárez Vázquez, Marcos; Varela Ballesta, Sylvana; Otero Cacho, Alberto; Pérez Muñuzuri, Alberto; Mira Pérez, Jorge; Universidade de Santiago de Compostela. Departamento de Física Aplicada; Universidade de Santiago de Compostela. Instituto de Materiais (iMATUS); Universidade de Santiago de Compostela. Departamento de Física de Partículas
In past years, several studies have proposed new methods and applications for urban wind simulations, including geometry reconstruction from urban data sources or improved boundary condition definition. In this article, we present a fast and automated methodology for reconstructing airflows within urban environments using LiDAR and cadastral data coupled with Computational Fluid Dynamics (CFD) simulations. Our approach integrates meteorological predictions with computational techniques to simulate the complex interactions between wind currents, buildings, vegetation, water zones and terrain morphology within urban environments. Accurate boundary conditions based on meteorological predictions are introduced into a coupled methodology that directly creates the terrain shape inside the simulation environment, simplifying the geometry creation process, which is one of the most prevalent problems in CFD urban simulations. The simulation results are confronted against ground-truth real data obtained from a meteorological station, showing strong agreement with the outcomes generated by the proposed CFD model, with a concordance correlation coefficient up to ρ and ρ c c =0.985 for the wind direction =0.853 for the wind speed. The results from these simulations are then used for validating a wind tunnel approach that mimics the interaction between a moving drone and the extracted wind currents, demonstrating a great improvement in computation times when compared to the most straightforward approach that consists in embedding the drone within the full urban landscape. This research contributes to the advancement of urban CFD modeling, and it has significant implications for various applications, providing valuable insights for urban development.
On the physical foundations of topological thermoelectricity and its improvement
(Elsevier, 2026-01-22) Baldomir Fernández, Daniel; Failde, Daniel; Universidade de Santiago de Compostela. Departamento de Física Aplicada; Universidade de Santiago de Compostela. Instituto de Materiais (iMATUS)
Thermoelectricity has extraordinary scientific and technological interest due to its ability to utilize heat losses through the Seebeck effect and Peltier cooling in circuits. However, the efficiency of thermoelectric materials remains relatively low, making them economically viable in fewer cases than desired. A promising possibility lies in the best thermoelectric materials at room temperature, specifically the well-known tetradymite-type structures, primarily compounds based on . These materials are characterized as topological insulators, allowing for the introduction of new physical perspectives. Therefore, it is reasonable to closely investigate the interplay between topology and thermoelectricity in these systems, with the aim of elucidating the underlying physical mechanisms. We show that, near the surface–bulk interface, the electrodynamics of axions coupled to massless fermions, Thouless pump currents, the chiral anomaly, and topological mass are intimately interconnected in a way that enables the mutual conversion of heat and electrical energy. That gives rise to a thermoelectric effect whose efficiency can be enhanced by integer multiples. We extend this study to heterostructures of topological insulators and topological superconductors. These phases are topologically complementary and may use the proximity effect to share topological quantum numbers. This offers a pathway to enhance topological thermoelectricity.
Exploring Visual Discrimination and Performance Adaptation in First-League Futsal Players via LUMMICS
(MDPI, 2026-04-23) Monteiro, Bruno; Roque, Ana; Nascimento, Henrique; Martínez Pérez, Clara
Background/Objectives: Perceptual–cognitive abilities such as visual discrimination, reaction time, and attentional control are important for performance in dynamic sports. However, evidence remains limited regarding how simplified visual tasks capture performance variability and dynamics under repeated exposure. This study examined session-to-session performance changes and individual trajectories in a programmable visual discrimination task of increasing complexity in elite futsal players. Methods: An exploratory repeated-measures study was conducted with ten first-league futsal players. Participants completed between six and ten sessions of a color-cue visual discrimination task (“Follow the Color”) under one- and two-stimulus conditions. Outcomes included correct responses, errors, and reaction time per session. A total of 465 observations were analyzed using linear mixed-effects models to assess changes across sessions and the influence of task complexity. Individual analyses were also performed to explore player-specific trajectories. Results: Mean session accuracy was 63.8 ± 9.8 correct responses, with a mean error rate of 3.6 ± 6.1 and a mean reaction time of 0.63 ± 0.15 s. Error rates declined significantly across sessions (β = −0.008, p < 0.001), while reaction time improved modestly (β = −0.00011, p = 0.025). Correct responses showed a small negative trend over time. Increased task complexity was associated with fewer correct responses, higher error rates, and slower reaction times (all p < 0.001). Conclusions: This programmable visual discrimination task captured variability in visuomotor responses under controlled conditions and may support monitoring of performance dynamics in sports vision research.
Biomimetic core-shell breast cancer models using alginate, gelatin, and collagen I: simulating the tumor matrix for drug evaluation
(Elsevier, 2026-01) Gato Díaz, Uxía; Castro Alves, Lisandra de; Concheiro Nine, Ángel Joaquín; Piñeiro Redondo, Yolanda; Álvarez Lorenzo, Carmen; Blanco Fernández, Bárbara; Rivas Rey, José; Universidade de Santiago de Compostela. Instituto de Materiais (iMATUS); Universidade de Santiago de Compostela. Departamento de Física Aplicada; Universidade de Santiago de Compostela. Departamento de Farmacoloxía, Farmacia e Tecnoloxía Farmacéutica
Breast cancer remains among the most prevalent cancers in women worldwide. During tumor development, the extracellular matrix is altered to support tumor progression and therapy resistance. Therefore, there is a need to develop breast cancer models that replicate the complex tumor extracellular matrix to accurately mimic the mechanisms by which it influences drug resistance and cancer cell malignancy. In this study, we fabricated an innovative breast cancer 3D in vitro model consisting of core-shell hydrogel beads from alginate, gelatin, and collagen I by extrusion through a coaxial needle. Breast cancer cells proliferated in the core of all prototypes designed, forming spheroids and cell aggregates with a high resistance to doxorubicin. The addition of Collagen I to the developed model enabled the upregulation of malignancy markers (Col1A1, Ki67, FOXC2, SNAI1, NFKB1, WWTR1), invasion markers (WASL, ACTA1, MYO1E, TPM4, PODXL, ITGA2, ITGA5, MENA, EGFR, CDC42), and drug resistance markers (ABCG2, CYP1A1, BAX, HSP90AA1) occurring in vivo. The developed 3D in vitro model can clarify the contribution of the extracellular matrix to the tumor outcome and drug efficacy by replicating some key characteristics of breast tumors, establishing a novel tool for chemotherapeutic agents and drug screening.
Surface-modified iron oxide nanoprobes in biomedical scaffolds
(Royal Society of Chemistry, 2025-11-17) González Gómez, Manuel Antonio; Arnosa Prieto, Ángela; García Acevedo, Pelayo; Díaz Rodríguez, Patricia; Castro Alves, Lisandra de; Piñeiro Redondo, Yolanda; Rivas Rey, José; Universidade de Santiago de Compostela. Instituto de Materiais (iMATUS); Universidade de Santiago de Compostela. Departamento de Física Aplicada
Magnetic (PU) scaffolds incorporating superparamagnetic iron oxide nanoparticles (SPIONs) offer a promising platform for localized cancer therapy. By enhancing the functional performance of these scaffolds through surface modification of iron oxide nanoprobes, their biomedical utility—particularly in targeted therapeutic applications—can be significantly improved. In this study, we report the synthesis and characterization of magnetite nanoparticles (Fe3O4 NPs) functionalized with biocompatible coatings—citrate, polyethylene glycol (PEG), oleic acid (OA), and aluminum hydroxide (Al(OH)3)—and their integration into porous PU scaffolds via a salt-leaching/phase-inversion method. Among all tested formulations, SPIONs@Al(OH) demonstrated superior colloidal stability, magnetic responsiveness, and cytocompatibility. When embedded in PU scaffolds, these magnetic nanocomposites exhibited optimal mesoporosity, homogeneous nanoparticle distribution, and efficient magnetic hyperthermia performance under clinically relevant alternating magnetic fields. This work highlights the synergistic potential of material design and surface engineering in developing next-generation implantable platforms for targeted oncological treatment.
Ligand-Driven Optimization of Iron Oxide Nanoprobes forIn Vivo MRI Enhancement at Ultra-High Field
(Wiley, 2026-02-03) García Acevedo, Pelayo; Alonso Alonso, María Luz; Ortega Espina, Sara; Bañobre López, Manuel; Piñeiro Redondo, Yolanda; Iglesias Rey, Ramón; Rivas Rey, José; Universidade de Santiago de Compostela. Departamento de Física Aplicada; Universidade de Santiago de Compostela. Instituto de Materiais (iMATUS)
Ultra-high-field magnetic resonance imaging (UHF-MRI, B0 > 7 T) combined with contrast enhancement (CE-MRI) offersunmatched spatial resolution, but high-field effects limit the performance of negative contrast agents. Here, we report a ligand-driven strategy to modulate the T2 relaxivity (r2 ) of monodisperse 12 nm iron oxide-based contrast agents synthesized by thermaldecomposition. Five surface chemistries–polyacrylic acid (PAA), poly(isobutylene-alt-maleic anhydride) (PMA), poly(maleicanhydride-alt-1-octadecene) (PMAO), citric acid (CA), and silica (SiO2 )─ were investigated under physiological conditions andin vivo using relaxometry (1.4 T), clinical (3 T), and UHF (9.4 T) MRI, achieving up to a 333 mm−1 s−1 increase in r2 . CA-coated T2contrast agents exhibited record-high r2 values (522 mm−1 s−1 at 3 T; 381 mm−1 s−1 at 9.4 T) in spherical iron oxide MNPs withinthe superparamagnetic size range (d < 20 nm). Correlations of r2 with hydrodynamic size, ζ-potential, and coating thicknessrevealed that ligand chemistry–specifically hydrophilicity and anionic surface charge–dominates over physical shell dimensionsin governing water accessibility and magnetic dephasing. This scalable ligand-exchange strategy enables precise T2 tuning at UHF,with phantom results reliably predicting in vivo UHF-MRI performance in rat brain models, advancing the design of neuroimaging nanoprobes.
Agreement Between Non-Cycloplegic Photorefraction and Retinoscopy in Pediatric Refraction
(MDPI, 2026-04-16) Roque, Ana; Nunes, Amélia Fernandes; Nascimento, Henrique; NIAOO Group; Martínez Pérez, Clara
Accurate assessment of refractive error in children is essential for clinical decision-making, yet agreement between non-cycloplegic techniques remains uncertain, particularly due to differences in accommodative demand. This study evaluated the agreement between static retinoscopy and handheld photorefraction for measuring spherical power, cylindrical power, and spherical equivalent in children aged 4–16 years and assessed whether agreement varied by refractive status. In this cross-sectional observational study, 193 children underwent objective refraction during a single visit using non-cycloplegic static retinoscopy (distance fixation) and handheld infrared photorefraction (~1 m fixation). Inter-method differences were analyzed using Bland–Altman plots, intraclass correlation coefficients (ICCs), mean absolute error (MAE), and non-parametric tests. Photorefraction showed a statistically significant myopic shift compared with retinoscopy for spherical power (−0.16 D), cylindrical power (−0.24 D), and spherical equivalent (−0.28 D). Agreement was moderate in statistical terms for spherical equivalent (ICC = 0.73) and spherical power (0.71), and lower for cylindrical power (0.46); however, wide limits of agreement indicate clinically relevant variability. MAE for spherical equivalent was 0.80 D overall, with 45.1% of measurements within ±0.50 D, and varied by refractive status, being lowest in emmetropic eyes and higher in hyperopic and myopic eyes. These findings indicate that, under non-cycloplegic conditions, photorefraction shows modest mean differences but substantial individual variability, likely influenced by differences in accommodative demand between techniques. While suitable for pediatric vision screening, photorefraction should not be considered interchangeable with retinoscopy for individual refractive assessment.
Multifunctional hybrid chitosan/κ-carrageenan sponges integrating engineered SBA-15@Fe3O4 composites and nano-hydroxyapatite for bone tissue engineering
(Elsevier, 2026-04) Vargas Osorio, Zulema; García Acevedo, Pelayo; Piñeiro Redondo, Yolanda; Michálek, Martin; Luzardo Álvarez, Asteria María; Otero Espinar, Francisco Javier; Boccaccini, Aldo Roberto; Rivas Rey, José; Universidade de Santiago de Compostela. Departamento de Física Aplicada; Universidade de Santiago de Compostela. Instituto de Materiais (iMATUS)
Conventional therapies often struggle to overcome key challenges associated with bone tissue disorders that demand advanced and sustained therapy solutions. This underscores the urgent need for multifunctional platforms that combine diagnostic and therapeutic functions with bioactive, degradable, and mechanically robust components. Herein, BDDE-crosslinked chitosan/κ-carrageenan sponges incorporating engineered SBA-15/Fe3O4 composites and nano-sized hydroxyapatite (nHAp) crystals were fabricated and investigated. The resulting hybrid sponges exhibited full shape recovery after mechanical compression under wet conditions and a remarkable absorption capacity without compromising their porous structure, attributed to strong structural integrity. The encapsulated SBA-15/Fe3O4 particles imparted hierarchical porosity and significant surface roughness, enabling high loading (≥150 mg/g) of simvastatin, a drug with potential to enhance bone regeneration, as well as its controlled release over extended periods ≥30 days. Additionally, these engineered composites conferred magnetic hyperthermia functionality, achieving specific absorption rates (SAR) ranging from 1.82 W·g−1 to 22.44 W·g−1 when applied a magnetic field of 28 mT at different kHz, providing them with the ability to modulate the heat response. The incorporation of nHAp into the sponge formulation enhanced both their bioactivity when tested in simulated physiological media, and cell adhesion and proliferation, as confirmed by in vitro direct and indirect contact assays. Cytocompatibility assessments using mouse macrophage (RAW 264.7), human osteosarcoma (MG-63), and preosteoblast (MC3T3-E1) cell lines demonstrated ≥80% viability across all models, revealing the highest proliferation in direct contact. These synergistic and versatile sponges hold promise for applications in bone tissue engineering.
Virtual Reality Orthoptic Interventions for Binocular Vision Disorders: A Systematic Review and Meta-Analysis
(MDPI, 2026-04-14) Martínez Pérez, Clara; Nores Palmas, Noelia; García Queiruga, Jacobo; Giráldez Fernández, María Jesús; Yebra-Pimentel Vilar, Eva
Purpose: To systematically review and meta-analyze randomized controlled trials (RCTs) evaluating digital orthoptic interventions, including virtual reality (VR)–based approaches, for convergence insufficiency and intermittent exotropia. Methods: This systematic review and meta-analysis followed PRISMA 2020 guidelines and AMSTAR-2 standards and was prospectively registered in PROSPERO. PubMed, Web of Science, and Scopus were searched up to December 2025. Eligible studies were RCTs comparing VR-based or digital orthoptic interventions with conventional therapy, placebo VR, or control conditions. Primary outcomes included near point of convergence, ocular deviation, fusional reserves, and stereopsis. Risk of bias was assessed using RoB 2 and certainty of evidence with GRADE. Results: Four RCTs (184 participants) were included. In convergence insufficiency, digital orthoptic interventions, including VR-based approaches, significantly reduced near heterophoria (mean difference [MD] −1.64 prism diopters; 95% CI −3.17 to −0.12), with no significant effects on near point of convergence or positive fusional reserves. In intermittent exotropia, VR-based interventions significantly improved near point of convergence (MD −1.60 cm; 95% CI −2.64 to −0.55), although this change did not reach the ≥4 cm threshold considered clinically meaningful according to the Convergence Insufficiency Treatment Trial. Improvements were also observed in stereopsis (MD −0.19 log units; 95% CI −0.33 to −0.04), while changes in near deviation were not significant. Evidence certainty ranged from low to moderate. Conclusions: VR-based and digital orthoptic interventions may offer modest, outcome-specific benefits as adjunctive treatments for selected binocular vision disorders. Larger, well-designed RCTs with standardized outcomes are needed.
Inverse Conformational Selection in Lipid–Protein Binding
(American Chemical Society, 2021-08-16) Bacle, Amélie; García Fandiño, Rebeca; Ferreira, Tiago M.; Piñeiro Guillén, Ángel; Virtanen, Salla I.; Universidade de Santiago de Compostela. Departamento de Química Física; Universidade de Santiago de Compostela. Centro de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS); Universidade de Santiago de Compostela. Departamento de Física Aplicada
Interest in lipid interactions with proteins and other biomolecules is emerging not only in fundamental biochemistry but also in the field of nanobiotechnology where lipids are commonly used, for example, in carriers of mRNA vaccines. The outward-facing components of cellular membranes and lipid nanoparticles, the lipid headgroups, regulate membrane interactions with approaching substances, such as proteins, drugs, RNA, or viruses. Because lipid headgroup conformational ensembles have not been experimentally determined in physiologically relevant conditions, an essential question about their interactions with other biomolecules remains unanswered: Do headgroups exchange between a few rigid structures, or fluctuate freely across a practically continuous spectrum of conformations? Here, we combine solid-state NMR experiments and molecular dynamics simulations from the NMRlipids Project to resolve the conformational ensembles of headgroups of four key lipid types in various biologically relevant conditions. We find that lipid headgroups sample a wide range of overlapping conformations in both neutral and charged cellular membranes, and that differences in the headgroup chemistry manifest only in probability distributions of conformations. Furthermore, the analysis of 894 protein-bound lipid structures from the Protein Data Bank suggests that lipids can bind to proteins in a wide range of conformations, which are not limited by the headgroup chemistry. We propose that lipids can select a suitable headgroup conformation from the wide range available to them to fit the various binding sites in proteins. The proposed inverse conformational selection model will extend also to lipid binding to targets other than proteins, such as drugs, RNA, and viruses.
Antimicrobial peptides at (lipid) interfaces: Insights from monolayer models
(Elsevier, 2026) Antelo Riveiro, Paula; García Fandiño, Rebeca; Piñeiro Guillén, Ángel; Universidade de Santiago de Compostela. Departamento de Química Orgánica; Universidade de Santiago de Compostela. Departamento de Física Aplicada; Universidade de Santiago de Compostela. Centro de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS)
Antimicrobial peptides (AMPs) are key effectors of innate immunity that, beyond their canonical activity, exhibit promising therapeutic potential against cancer and cellular senescence. Their efficacy relies on selective membrane disruption driven by specific lipid signatures, yet quantifying these interactions in complex bilayer systems remains challenging. Lipid monolayers serve as powerful reductionist models to isolate the physicochemical determinants of this selectivity, effectively mimicking the outer leaflet of bacterial, cancerous, or senescent membranes. This review provides a critical analysis of how lipid composition, packing density, and phase behavior modulate AMP adsorption and insertion. We systematically integrate thermodynamic profiling (surface pressure, compressibility, mixing energy) with advanced structural and morphological characterization. Special emphasis is placed on how spectroscopic techniques (IRRAS, GIXD, SFG) and real-time microscopy (BAM, fluorescence, AFM) resolve peptide orientation, secondary structure induction, and lipid domain remodeling at the mesoscale. These experimental observables are bridged with Molecular Dynamics (MD) simulations, establishing a feedback loop between macroscopic measurements and atomistic resolution. By defining the advantages and limitations of monolayer models relative to vesicles and bilayers, we outline a rational framework for leveraging interfacial insights in the design of next-generation peptide therapeutics and nanobiotechnological applications.
A review of the last 10 years regarding protein and lipid deposition on soft contact lenses
(Elsevier, 2026) García Queiruga, Jacobo; Nores Palmas, Noelia; Martínez Pérez, Clara
Purpose To synthesize recent evidence on protein and lipid deposition on soft contact lenses (CLs) and to clarify how material chemistry and surface properties influence biomolecule interactions. Methods A structured narrative review of studies published between 2015 and 2025 was conducted, and the review protocol was registered in the PROSPERO database (registration number: CRD420261333929). Electronic searches of PubMed, Web of Science, and Scopus identified in vitro, ex vivo, and in vivo investigations evaluating protein and/or lipid interactions with hydrogel and silicone hydrogel (SiHy) CL materials. Data were qualitatively synthesized according to material class, surface modification strategy, biomolecule type, localization, and reported functional outcomes. Results Fourteen studies met the inclusion criteria. Ionic, high–water content hydrogels consistently exhibited high protein uptake, predominantly through bulk absorption, while preserving enzymatic activity of key tear proteins such as lysozyme. In contrast, unmodified SiHy CLs showed lower total protein deposition but greater susceptibility to nonpolar lipid adsorption. Imaging-based analyses revealed that surface-localized lipid deposition had greater functional relevance than bulk lipid diffusion. Biomimetic surface-modified SiHy incorporating MPC or PMPC demonstrated marked resistance to surface-associated protein and lipid fouling. Conclusion Protein and lipid deposition on soft CLs is primarily governed by material chemistry and surface design rather than deposition quantity alone. Surface-associated fouling, especially lipid adsorption, plays a central role in tear film instability, supporting a functional, material-dependent framework for evaluating and optimizing contact lens performance.
Visual and Oculomotor Function in Developmental Dyslexia: A Systematic Review and Meta-Analysis
(Springer, 2026-03-09) Martínez Pérez, Clara; Oliveira, Ana Paula; Baltazar, Isabel; Universidade de Santiago de Compostela. Departamento de Física Aplicada
Topic To determine whether individuals with developmental dyslexia present differences in visual and oculomotor functions compared with age-matched controls. Clinical Relevance Developmental dyslexia affects a substantial proportion of school-aged children, with prevalence estimates ranging between 3% and 6%, depending on diagnostic criteria. It is characterised by persistent reading difficulties despite normal intelligence and education. Although phonological deficits are well established, the contribution of visual and oculomotor anomalies remains debated. Identifying consistent visual differences may support more comprehensive assessments and targeted interventions alongside educational strategies. Methods This systematic review and meta-analysis, registered in PROSPERO (CRD420251119429), included observational case-control studies comparing visual and oculomotor functions in individuals with developmental dyslexia and age-matched controls. Searches were conducted in PubMed, Web of Science, and Scopus. Outcomes included binocular vision, oculomotor performance, accommodation, visual acuity, refractive error and contrast sensitivity. Methodological quality was assessed using the MINORS tool and certainty of evidence using GRADE. Results Twenty-six studies with 8 to 124 participants per group were included. Dyslexic individuals showed significantly greater near exophoria (mean difference 0.84 prism diopters, 95% CI: 0.22 to 1.46) and reduced near fusional vergence ranges, including negative (–6.42 prism diopters, 95% CI: –8.65 to –4.19) and positive fusional vergence (–6.72 prism diopters, 95% CI: –8.66 to –4.77), all p < 0.01. Oculomotor differences included a higher number of fixations, longer fixation duration, more regressions and reduced saccade amplitude. No significant group differences were found for refractive error or visual acuity. Conclusions Children with developmental dyslexia exhibit consistent binocular and oculomotor anomalies that may increase visual effort during reading. Incorporating targeted assessment of these functions into vision care may complement multidisciplinary management. Further research is needed to clarify their clinical relevance.

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