Artículos (Física de la Materia Condensada)

URI permanente para esta colecciónhttps://hdl.handle.net/11441/10869

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Characterizing the Carnot cycle at absolute zero: a reply to “Comment on ‘Proof of the Nernst theorem’ ”
(Springer Nature, 2026) Martín Olalla, José María; Física de la Materia Condensada; Universidad de Sevilla/CBUA
This reply addresses a recent comment concerning the proof of the Nernst theorem. I clarify how a Carnot engine can consistently operate at T = 0 through a continuous deformation of a cycle operating at T > 0. By examining the limit where heat exchange with the cold reservoir vanishes, I show that the Nernst theorem ensures that the concept of temperature remains physically consistent at the absolute zero limit. SuppInfo is a pdf animation showing the characterization of T=0 through a limit Carnot engine. The animation requires a pdf viewer with javascript enabled.
Antimicrobial efficacy of multipurpose and oxidative contact lens disinfecting solutions: a systematic review
(Elsevier, 2025-04) Ponce García, Víctor; García Romera, Marta de la Concepción; Silva Viguera, María del Carmen; Bautista Llamas, María José; Física de la Materia Condensada
Purpose: To systematically review the antimicrobial efficacy of multipurpose solutions (MPS) and oxidative systems, hydrogen peroxide (H2O2) and povidone-iodine (PVP-I), used for contact lens disinfection. Methods: A systematic search of PubMed and Scopus was conducted according to PRISMA guidelines. Eligible studies compared commercial disinfecting systems using ISO 14729 reference strains or clinically relevant isolates. Extracted data included disinfectant agents, microorganisms tested, ISO compliance, test methodology, and reported outcomes. Results: Ten studies were included in this systematic review. Oxidative systems (H2O2 and PVP-I) consistently achieved strong antimicrobial effects, often maintaining efficacy in the presence of organic soil, biofilms, or clinical isolates. In contrast, MPS showed variable performance depending on their active biocides with several studies reporting reduced efficacy against fungi and Acanthamoeba cysts. Although all solutions typically met ISO 14729 criteria, several studies showed markedly reduced efficacy under clinically relevant conditions. Conclusion: Oxidative systems demonstrated superior antimicrobial efficacy compared to MPS, particularly under challenging conditions and against resistant microorganisms. Given that ISO 14729 does not account for pathogens such as Acanthamoeba spp. or clinically resistant strains, reliance on this standard may overestimate real-world efficacy. Expanding testing requirements to include a broader spectrum of microorganisms would provide a more realistic evaluation of disinfecting systems and ultimately strengthen safety for contact lens wearers.
Giant room-temperature magnetocaloric effect MM′X alloys explored by machine learning
(Elsevier, 2025-07-17) Qiao, Kaiming; Cui, Zhe; Hao, Xiaowen; Zhao, Qian; Xu, Yuanxiang; Wang, Dekun; Romero-Muñiz, Carlos; Law, Jia Yan; Franco García, Victorino; Ren, Qingyong; Zhang, Hu; Física de la Materia Condensada; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Agencia Estatal de Investigación. España
Magnetic refrigeration is emerging as a promising alternative to conventional gas compression refrigeration. The key to advancing this technology lies in identifying materials with high magnetocaloric effect (MCE). However, traditional experimental methods require time-consuming and labor-intensive experimentation to screen compositions. Herein, we developed a machine learning (ML) model utilizing the Random Forest algorithm to efficiently identify MM'X alloy compositions with giant MCE near room temperature based on a small dataset (<200). The ML-predicted results were perfectly confirmed by the validation experiments. Notably, while most typical magnetic refrigeration materials near room temperature show a maximum ∆S around or <20 kg-1 K-1(0–5 T), our predicted alloys show a remarkable ∆S of up to 51 kg-1 K-1, which is more than four times higher than that of the benchmark material, Gd. The origin of this giant MCE is linked to atomic disorder and lattice ∆S predominantly from Ni atoms, as confirmed through spherical aberration corrected transmission electron microscopy, neutron powder diffraction and element-resolved vibrational density of states analysis. This work accelerates the discovery of magnetic refrigerants and significantly promotes the development of magnetic refrigeration.
Letter Regarding: Quantum Molecular Resonance Effects on Patients with Dry Eye Disease
(2025-06) Ballesteros Sánchez, Antonio; Rocha de Lossada, Carlos; Sánchez González, José María; Borroni, Davide; Física de la Materia Condensada; Cirugía
Structure and Defect Identification at Self-Assembled Islands of CO2 Using Scanning Probe Microscopy
(American Chemical Society, 2024-09-17) Custance, Oscar; Ventura-Macías, Emiliano; Stetsovych, Oleksandr; Romero Muñiz, Carlos; Shimizu, Tomoko K.; Pou, Pablo; Abe, Masayuki; Hayashi, Hironobu; Ohkubo, Tadakatsu; Pérez, Rubén; Física de la Materia Condensada; Ministry of Education, Culture, Sports, Science and Technology of Japan; Ministerio de Ciencia e Innovación (MICIN). España
Association between the use of prostaglandin analogues and ocular surface disease: a systematic review
(Springer Nature, 2024-10-08) Monge Carmona, Raquel; Caro Magdaleno, Manuel; Sánchez González, María del Carmen; Cirugía; Física de la Materia Condensada; Instituto de Salud Carlos III; Ministerio de Ciencia e Innovación (MICIN). España; European Union (UE)
Patients with glaucoma often experience chronic ocular surface diseases, potentially underestimated in frequency and severity. To provide updated estimates of ocular surface diseases linked to prostaglandin analogue antiglaucoma eye medication, a systematic review was conducted. Twenty-seven publications were selected from databases like PubMed, Scopus, and Web of Science, following a search strategy targeting glaucoma and prostaglandins while excluding certain medications ('(Glaucoma AND prostaglandins OR ‘prostaglandin analogues’)(‘eye drops’ OR ‘artificial tears’ OR ‘ocular surface’ OR ‘dry eye’ OR ‘dry eye syndrome’ OR ‘ocular surface disease’ OR ‘tear film’) NOT (‘beta blockers’ OR ‘alpha adrenergic agonists’ OR ‘carbonic anhydrase inhibitors’ OR ‘rho-quinase’)'. The review revealed a correlation between prostaglandin analogue use and ocular surface damage, assessing parameters such as tear break-up time, Schirmer test value, ocular surface staining, hyperaemia score, and meibomian gland characteristics. Some studies explored switching patients to alternative glaucoma medications, noting varied effects on ocular surface parameters. Comparisons suggested better tolerance and outcomes with preservative-free options over prostaglandins. Additionally, the impact of treatment duration and diquafosol on ocular health, including meibomian gland loss, was examined across different formulations. Although a link between prostaglandin analogues (with or without preservatives) and ocular surface damage was established, inconsistencies in methodologies and assessment across studies were noted. This comprehensive review, spanning a decade of glaucoma research, underscores the need for re-evaluation of treatment strategies in ophthalmology. It stresses the significance of informed decision-making for enhanced glaucoma care, taking into account the observed effects of various medications on eye health.
Síntesis de zβ a partir de cenizas volantes, utilizadas en liberación controlada de nitratos
(Universidad Pedagógica y Tecnológica de Colombia, 2020-06-19) García Barrero, Jenny Andrea; Pazos Zarama, Mery Carolina; Chaparro Barajas, Javier Ramiro; Fonseca Martínez, Deisy Alejandra; Pavón González, Esperanza; Alba Carranza, María Dolores; Física de la Materia Condensada
En este trabajo se sintetizó zeolita beta (Zβ) usando cenizas volantes (CV) de la central eléctrica de carbón, Termopaipa, situada en Paipa, Boyacá (Colombia). Las cenizas se utilizaron para extraer el silicio (Si) y aluminio (Al), para lo cual se realizó un pretratamiento ácido seguido de proceso hidrotérmico con NaOH. Para la obtención de la zeolita beta se varió la fuente de silicio y aluminio del gel madre y el tiempo de cristalización, manteniendo una composición nominal igual a 50SiO2: 1Al2O3: 25TEAOH: Na2O: K2O: 17H2O. En el primer experimento, las CV aportaron la fuente de aluminio, mientras que la fuente de silicio se obtuvo a partir de las CV y sílice fumante. La síntesis hidrotérmica se realizó a 170 °C durante 40 h, lo cual condujo a la obtención de ZSM-5 junto con una fase secundaria de mordenita. En el segundo experimento, las CV aportaron la fuente de silicio y se requirió la adición de sulfato de aluminio octadecahidratado como fuente de aluminio. La síntesis hidrotérmica se realizó a 170 °C y 60 h, lo cual condujo a una Zβ de alta pureza. Las zeolitas se caracterizaron usando DRX, FTIR, SEM y XRF. Las zeolitas se modificaron usando (3-aminopropil) trietóxisilano (APTES) y bromuro de hexadeciltrimetilamonio (HDTMA-Br). Los resultados muestran que la Zβ-APTES, con una capacidad de adsorción de 5 mmol NO3 -/100g tiene el mayor potencial para la aplicación de liberación controlada de fertilizantes.
Laser-Induced Graphene: A Promising Conductive Platform for Cell Culture
(Wiley, 2025-08-11) de Almeida, Henrique V.; Inácio, José Manuel; Pereira, Cláudia; Pinheiro, Tomás; Calmeiro, Tomás; Correia, Ricardo; Coelho, João; Pinto, Joana V.; Belo, José Antonio; Martins, Rodrigo; Fortunato, Elvira; Física de la Materia Condensada; Fundação para a Ciência e a Tecnologia; LIGHEART; Scientific Employment Stimulus; European Union (UE); Pacto Bioeconomia Azul; From Fossil to Forrest
Cardiovascular mortality remains a major health challenge. Cardiomyocyte (CM)-based tissue engineering (TE) offers promising alternatives for developing therapies via in vitro models. However, the immature phenotype of CM in engineered tissues hampers progress. Recent studies introduce conductive materials like graphene to enhance CM maturation, but conventional graphene synthesis suffers from complexity, toxicity, and low yield. Laser-induced graphene (LIG) provides a sustainable, cost-effective, eco-friendly solution with efficient conductivity and biocompatibility. A LIG-based substrate is bioengineered in this study, hypothesizing that its conductive, anisotropic properties promote CM maturation and mimic the native cardiac niche. LIG is fabricated using a CO2 laser with Parylene-C as a precursor. Stem cells (SCs) and SC-derived embryoid bodies (EBs) are cultured on LIG substrates, and their viability, metabolic activity, morphology, and protein expression are evaluated through immunofluorescence and electron microscopy. Both SCs and EBs maintain viability and activity throughout the culture. Moreover, EB-derived CM exhibit spontaneous contraction and express cardiac-specific proteins, confirming functional differentiation on LIG matrices. This first report demonstrates that LIG substrates support SC culture and differentiation, highlighting their potential in developing refined in vitro cardiac models and advancing regenerative therapeutic strategies. The findings support LIG as a transformative advancement in TE.
Re: Reply to Prof. Jacqueline Tan's letter. Efficacy of eyelid warming devices as a first-step treatment in meibomian gland dysfunction: A systematic review with meta-analysis. 2025; 37:33-46
(2025-04-17) Ballesteros Sánchez, Antonio; Rocha de Lossada, Carlos; Sánchez González, José María; Cirugía; Física de la Materia Condensada
New developments in the management of persistent corneal epithelial defects
(2024) García Lorente, María; Rodriguez-Calvo-De-Mora, Marina; Sánchez González, José María; Borroni, Davide; Zamorano-Martín, Francisco; Rocha de Lossada, Carlos; Física de la Materia Condensada; Cirugía
Influence of Lighting, Accommodation and Pharmacological Conditions on Vault After ICL Implant-Refractive Surgery: A Systematic Review
(Slack Journals, 2025-06-01) Aguilar Salazar, Francisco Javier; Cano Ortiz, Antonio; González Cruces, Timoteo; Sánchez González, José María; Física de la Materia Condensada
Purpose: To determine the influence of lighting conditions, accommodation, and the use of drugs on vault measurement in patients implanted with an Implantable Collamer Lens (ICL). This is the first systematic review to date that analyses published articles assessing vault variation when measured under different lighting, accommodative, and pharmacological conditions. Methods: A systematic review was conducted, including studies reporting vault measurement under different lighting, accommodative, or pharmacological conditions, in two databases: PubMed and Scopus. The search period was from February 2004 to December 14, 2024. The review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and the National Heart, Lung, and Blood Institute's Quality Assessment Tool for Case Series Studies was used to evaluate the quality of the included studies. Results: This systematic review included 22 studies and a total of 1690 eyes from 1094 patients. The influence of lighting conditions, accommodation, and drug use was analyzed in 13, 8, and 6 studies, respectively. Vault decreased from 542.12 ± 103.35 μm to 442.94 ± 102.76 μm (p < 0.001) when measured under photopic lighting conditions, this reduction was more evident in patients implanted with V4c models compared to V3 and V4 models. Conclusion The value of the vault is susceptible to changes depending on the conditions under which it is measured. The vault decreases under photopic lighting conditions, as well as during the accommodative state and after administration of miotic and mydriatic drugs.
Thermal annealing reduction of ALD hematite into magnetite nanotubes: Optimized magneto-structural properties for multifunctional applications
(Elsevier, 2026-05-26) Caballero Flores, Rafael; Méndez, Miguel; Vega, Victor; Adawy, Alaa; Ipus Bados, Jhon Jairo; Barriga-Castro, Enrique D.; Luna, Carlos; Prida, Victor M.; Física de la Materia Condensada; Ministerio de Ciencia e Innovación (MICIN). España; Agencia Estatal de Investigación. España; Principado de Asturias
The fabrication of 3D nanomagnetic materials with controlled geometry, composition, microstructure and magnetic properties is crucial for developing multifunctional devices with nanotechnological applications. Here we report on the synthesis of high-quality magnetite nanotubes using the thermal reduction treatment of hematite precursor deposited by atomic layer deposition technique within the hexagonally self-ordered nanopores of an anodic alumina membrane, employed as patterned template. The applied synthesis procedure adequately controls both the geometric parameters of the alumina template (pore length and diameter, interpore distance and porosity) and the single nanotube (wall thickness and inner diameter). Microstructural and magnetic characterizations confirm the complete phase conversion from weak magnetic hematite to ferrimagnetic magnetite, clearly evidenced by the sharp Verwey metal-insulator transition observed at ~120 K in the temperature-dependent magnetization curves. The magnetite/hematite ratio estimated using both M¨ ossbauer and Raman spectroscopies yield consistent values of approximately 70% magnetite and 30% hematite. Assessing the coercive field and reduced remanence dependences on nanotube wall thickness reveals the influence of magnetic shape anisotropy, evidenced by coercive field and reduced remanence values being consistently higher when the field is applied parallel to the nanotube longitudinal axis, and showing a critical dependence on nanotube wall thickness reaching a maximum value at 10 nm before stabilizing for larger values. The micromagnetic simulations performed by Mumax3 software reproduce also this magnetic behavior, unveiling the formation of a C-state magnetic domain during the magnetization reversal of a single magnetite nanotube with 2 nm in wall thickness. Therefore, these results demonstrate the effectiveness of the applied methodology to obtain magnetite nanostructures with optimized geometrical and magneto-structural properties, positioning them as promising candidates for applications in spintronics and magnetic sensing
Role of nanotwin-confined threading dislocations in the ultra-high hardness of B₁₀C ceramics
(Elsevier, 2026-05-04) Keshtkar, N.; López Arenal, Jesús; Moshtaghion, Bibi Malmal; Cumbrera Hernández, Francisco Luis; Gómez García, Diego; Física de la Materia Condensada; Ingeniería y Ciencia de los Materiales y del Transporte; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Agencia Estatal de Investigación. España
A highly nano-twinned boron-rich boron carbide, ≈ B10C, has been prepared efficiently through high energy ball milling (HEBM) of elemental boron and carbon powders followed by spark plasma sintering (SPS). Prolonged mechanical activation by HEBM significantly enhances reactive SPS sinterability and leads to a submicrometric microstructure with an average grain size of 0.47 μm. A high density of nano-twins is observed in most grains, with an average twin spacing of λ = 5.1 nm. The mechanical response (Hv~34 GPa) is strongly correlated with the extensive presence of nano twining and the associated confinement of dislocations. The observed ultra-high hardness can be rationalized using the classical Foreman model, originally developed to describe threading dislocations in stressed, capped epitaxial semiconductor layers.
Landau–Lifshitz–Bloch simulations of the magnetocaloric effect in continuous ferromagnetic–paramagnetic transitions
(Elsevier, 2026-03-19) Moreno Ramírez, Luis Miguel; Sánchez Tejerina, Luis; Alejos, Óscar; Franco García, Victorino; Raposo, Víctor; Física de la Materia Condensada; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Agencia Estatal de Investigación. España; European Union (UE)
The usefulness of modeling magnetocaloric materials expands from the understanding of their behavior to the prediction of new materials, playing a fundamental role in the optimization of their performance. In contrast with other areas of magnetic materials research, micromagnetic simulations of magnetocaloric materials are scarce due to the difficulty of modeling the material in the vicinity of the transition. To solve this limitation, we propose to use the Landau–Lifshitz–Bloch micromagnetic simulations to study the magnetocaloric effect associated with a second-order ferromagnetic↔paramagnetic transition. Following our proposed methodology and considering material parameters in a mean-field framework, we obtain reliable isothermal entropy change curves for monocrystalline and polycrystalline configurations, where we consider different anisotropic contributions. The robustness of the method was evaluated, yielding results that agreed with previous experimental and theoretical observations. Our study shows that micromagnetic simulations are a powerful tool for analyzing second-order magnetocaloric materials with complex microstructures.
Ocular Surface Microbiota in Primary Open Angle Glaucoma
(Elsevier, 2026-01) Borroni, Davide; Lo Monaco, Francesco; Ferraro, Silvia; Mazzotta, Cosimo; Settino, Marzia; Gabrielli, Federico; Rocha de Lossada, Carlos; Ballesteros Sánchez, Antonio; Zeppieri, Marco; Gagliano, Caterina; Cirugía; Física de la Materia Condensada
Aim: To characterize ocular surface microbiota of glaucoma patients undergoing hypotensive topical therapy. Methods Healthy and Primary Open Angle Glaucoma (POAG) ocular surface samples were collected using the Copan eNat® Collection System, and microbial DNA was extracted using the QIAmp DNA Microbiome Kit. The 16S rRNA sequencing was performed using the Ion GeneStudio™ S5 platform, and microbial diversity was analyzed using phyloseq, vegan, and DESeq2 in R. Alpha diversity was assessed using the Shannon Index and Observed Richness, while beta diversity was evaluated using Principal Coordinates Analysis (PCoA) and PERMANOVA. Differential abundance analysis was performed to identify key microbial taxa distinguishing the two groups. Results 195 individuals were included in the study, comprising 167 healthy controls and 28 glaucoma patients. Glaucoma patients exhibited a significant reduction in microbial diversity compared to controls (Shannon Index: p_adj = 5.97 × 10⁻⁷; Observed Richness: p_adj = 1.70 × 10⁻⁸). Beta diversity analysis (PERMANOVA, p = 0.001, R² = 0.063) demonstrated significant microbial community shifts between the two groups. Firmicutes were significantly reduced, while Proteobacteria were enriched in glaucoma patients. At the genus level, Staphylococcus was predominant in controls, whereas Pseudomonas and Unclassified Enterobacterales were significantly enriched in glaucoma patients. Differential abundance analysis further identified microbial signatures distinguishing glaucoma from healthy individuals. Conclusion This study provides evidence of microbial dysbiosis in glaucoma patients characterized by reduced diversity and shifts in key bacterial taxa.
Punctal occlusion versus artificial tears and lid hygiene in the management of Dry Anophthalmic Socket Syndrome: a randomized controlled trial
(Open Library of Humanities, 2025-05-06) Zamorano Martín, Francisco; Rebollo-Ramírez, Wolfgang; Ballesteros Sánchez, Antonio; Alba Linero, Carmen; Ortiz Pérez, Santiago; Tovilla Canales, Juan Luis; Nava Castañeda, Ángel; Física de la Materia Condensada
Blink rate self-regulation, tear volume and ocular symptoms in expert and naïve action video game players
(Taylor and Francis Group, 2026-03-01) Argilés, Marc; Ruiz-Sánchez, Patricia; Ballesteros Sánchez, Antonio; Valentino, Maite; Cardona, Genis; Física de la Materia Condensada; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Agencia Estatal de Investigación. España; European Union (UE)
Clinical relevance: Alterations in blink rate and dynamics are common during visually demanding tasks such as video gaming or digital device use, leading to tear film instability and ocular and visual symptoms. Background: Sustained visual attention during gaming may reduce blink frequency and alter tear production, increasing ocular surface symptoms. The aim of this study was to determine whether experienced action video game (AVG) players exhibited adaptations in blink rate and tear volume compared with non-video game (NVG) players, and to explore the relationship between these adaptations and ocular symptoms. Methods: Thirty participants (17 AVG and 13 NVG) were enrolled. All participants played Call of Duty: Modern Warfare® (Zombies mode) for minutes under controlled conditions. Blink rate was recorded at baseline and during dynamic and non-dynamic scenes using the Pupil Core eye tracker. Tear volume was assessed with the Schirmer test before and after gameplay. Dry eye symptoms were evaluated using the SANDE questionnaire at baseline and the IOSS questionnaire every five minutes during gameplay. Results: No significant group differences were observed at baseline in blink rate, tear volume, or SANDE scores (all p > 0.05). During gameplay, AVG players exhibited significantly lower blink rates than NVG players in both dynamic (5.94 ± 2.61 vs. 7.88 ± 2.40 blinks/min, p = 0.045) and non-dynamic scenes (10.44 ± 3.34 vs. 13.73 ± 3.82 blinks/min, p = 0.018). Schirmer test values did not differ significantly pre–post session (p > 0.05). IOSS scores increased during gameplay in both groups (p < 0.0001), appearing earlier in NVG players. Conclusion: Expert AVG players demonstrate altered blink behaviour compared with NVG players, possibly reflecting adaptations that minimize visual information loss. These adaptations may influence ocular surface health during prolonged visual tasks. Further research is warranted to clarify the mechanisms underlying these changes.
Full solid-state magnetic refrigeration device toward thermal management
(Proceedings of the National Academy of Sciences, 2026) Lin, Yuan; Franco García, Victorino; Wang, Jing; Law, Jia Yan; Chen, Yunzhong; Sun, Jirong; Física de la Materia Condensada; National Natural Science Foundation of China; Agencia Estatal de Investigación. España; European Union (UE); Ministerio de Hacienda y Función Pública; Junta de Andalucía
The demand for thermal management of electronics is rapidly increasing due to the prosperity of information technology. However, the two major alternatives, convective cooling and vapor compression technologies, have limitations for the effective refrigeration of microchips, namely the low convective heat-transfer coefficient of gas, and the need of large compressors, not to mention the low efficiency of compressor cooling and its use of greenhouse refrigerant. Herein, we establish a full solid-state magnetic refrigeration device with scalability and simple structure based on hybrid regeneration utilizing solid heat transfer materials, aiming at offering active point-to-point thermal management through solid-to-solid contact to targets with different footprints. Even with the intrinsic experimental imperfections of a laboratory demonstrator, the device shows a high heat-transfer coefficient h of 336 W m−2 K−1 (typically forced air convection by electric fans have <100 W m−2 K−1), a high unit cascade heat-transfer coefficient h/n of 168 W m−2 K−1, and a large area cooling power W of 0.72 W cm−2 at the temperature difference between environment Te and hot object To of −20 K, which make our full solid-state design the best in the field of thermal management compared to reported full solid-state caloric devices.
Epithelial thickness gradients as a diagnostic biomarker for early-stage keratoconus
(Springer, 2026) Jansone-Langina, Zane; Gertnere, Jana; Kezika, Viktorija; Rocha de Lossada, Carlos; Sánchez González, José María; Cirugía; Física de la Materia Condensada; Universidad de Sevilla
Purpose: To evaluate peripheral-central epithelial thickness (ET) gradients in eyes with keratoconus and regular astigmatism, and to determine their potential utility as a non-invasive biomarker for disease detection in early-stage keratoconus. Methods: This retrospective cross-sectional analyzed ET with spectral-domain OCT at the cone apex and at 3 mm in the superior, temporal, nasal, and inferior directions. Epithelial thickness gradients (ΔET) were calculated as the difference between peripheral and central ET. Statistical comparisons were performed using non-parametric tests, with significance set at p < 0.05. Results: A total of 396 eyes (208 keratoconus, 188 regular astigmatism) were analyzed. Central ET was significantly reduced in KC (38.55 ± 5.42 µm) vs controls (48.78 ± 3.94 µm; p < 0.001). While peripheral thickness showed minor differences, the ET gradients (ΔET) were markedly steeper in KC across all quadrants (temporal, superior, nasal, inferior, p < 0.001). Within Stage I KC, eyes with more advanced disease exhibited steeper ΔET values, particularly in the nasal and temporal directions. Mean ΔET, demonstrated significant differences between KC (8.43 ± 4.97 µm) and controls (− 1.55 ± 1.77 µm; p < 0.001), and correlated positively with steep keratometry (r = 0.521, p < 0.001) and negatively with thinnest corneal thickness (TCT) (r = − 0.641, p < 0.001). Conclusion: ΔET is markedly steeper in keratoconus than in regular astigmatism—even in Stage I—and correlates with steep keratometry and TCT. With areas under the curves (AUCs) up to 0.976, ΔET provides a rapid, non-invasive epithelial-based biomarker for early detection and staging of keratoconus. Its utility for monitoring progression remains to be established in prospective longitudinal studies.
Additive manufacturing meets thermomagnetic heat recovery: NiMn-based Heusler composites
(Elsevier, 2026) Gallo, Lorenzo; Garulli, Giovanni; Law, Jia Yan; Fabbrici, Simone; Cugini, Francesco; Trevisi, Giovanna; Solzi, Massimo; Franco García, Victorino; Albertini, Franca; Física de la Materia Condensada; European Union (UE); Italian Ministry of University and Research; Agencia Estatal de Investigación. España; Ministerio de Hacienda y Función Pública. España; Junta de Andalucía
Over 70% of global primary energy is lost as waste heat, with nearly half of these losses occurring below 100◦C, a largely untapped resource for sustainable energy conversion. Thermomagnetic (TM) technologies offer a promising route to exploit this low-grade heat, yet their scalability has been hindered by limitations in materials processing and device design. Here, we introduce an additive manufacturing (AM) strategy to fabricate TM composite rotors, embedding NiMn-based Heusler alloys into polymeric filaments via a simple capsule-filling method. The resulting FDM-compatible filaments were printed into thin, mechanically robust rotors that preserve the intrinsic Curie transitions of the active powders. In-operando testing in a Curie-wheel prototype demonstrates clear TM responses, with Ni₄₈Mn₃₆In₁₆-based rotors delivering up to 55% higher power output tan Ni₄₈Mn₃₆Sn₁₆ counterparts. A systematic study of rotor thickness further reveals a ~5% enhancement in performance for thinner geometries, highlighting the decisive role of surface-to-volume ratio in thermal Exchange efficiency. This work establishes the first successful realization of 3D-printed TM rotors for energy harvesting, demonstrating that AM can precisely tailor geometry and material distribution to create lightweight, high-surface-area components optimized for low-grade waste heat recovery.

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