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The Casimir-Lifshitz force, FC − L, has become a subject of great interest to both theoretical and applied physics communities due to its fundamental properties and potential technological implications in emerging nano-scale devices. Recent cutting-edge experiments have demonstrated the potential of quantum trapping at the nano-scale assisted by FC − L in metallic planar plates immersed in fluids through appropriate stratification of the inner dielectric media, opening up new avenues for exploring physics at the nano-scale. This review article provides an overview of the latest results in Casimir-Lifshitz based-optical resonator schemes and their potential applications in fields such as microfluidic devices, bio-nano and micro electromechanical systems (NEMS and MEMS), strong coupling, polaritonic chemistry, photo-chemistry, sensing, and metrology. The use of these optical resonators provides a versatile platform for fundamental studies and technological applications at the nano-scale, with the potential to revolutionize various fields and create new opportunities for research.

Antecedentes El Síndrome de ojo seco (DED) asociado a la disfunción de glándulas de Meibomio (MGD) es la forma más común de ojo seco. Actualmente, el tratamiento convencional, que se basa en terapia domiciliaria, solo suele conseguir un alivio temporal de los síntomas y signos . Además, la tasa de cumplimiento de este tratamiento es baja . Por ello, el objetivo principal de esta tesis doctoral es determinar la seguridad y eficacia de un nuevo tratamiento combinado de micro blefaroexfoliación (MBE), luz pulsada intensa (IPL) y expresión de glándulas de Meibomio (MGX). Metodología Se ha realizado una tesis doctoral de carácter industrial y por compendio de publicaciones. Para responder al objetivo principal de la tesis, se llevó a cabo un ensayo clínico controlado. Previamente, se revisaron sistemáticamente la seguridad y eficacia de la MBE, terapias con luz y MGX de forma individual. Posteriormente, se real izó un estudio longitudinal para determinar la repetibilidad intra observador de la lámpara de hendidura S390L Firefly WDR, utilizada en la medición de variables analizadas en el ensayo clínico controlado. Resultados El tratamiento combinado de MBE-IPL-MGX obtuvo resultados significativamente superiores con respecto a la terapia domiciliaria en aquellas variables relacionas con los síntomas de ojo seco, así como con la estabilidad de la película lagrimal, la morfología de las glándulas de Meibomio y su secreción. Además, la mejoría en la puntuación de secreción de las glándulas de Meibomio (MGYSS) fue significativamente superior en los grados 2 y 3 de MGD. En términos de seguridad, se reportó un 18 3 ± 10 1% de efectos adversos (AEs). En cuanto a las revisiones sistemáticas, la MBE consiguió una mayor reducción de los síntomas y signos que la terapia domiciliaria, así como una mayor liberación de meibum . Las terapias con luz mostraron resultados similares, destacando la mejoría de la calidad del meibum. Sin embargo, La MGX combinada con terapia domiciliaria solo, Background Dry eye disease (DED) associated with Meibomian gland dysfunction (MGD) is the most common form of dry eye. Currently, conventional treatment, which is based on home therapy, usually only achieves temporary relief of symptoms and signs. Moreover, the compliance of this treatment is low. Therefore, the main objective of this doctoral thesis is to determine the safety and efficacy of a new combined treatment of micro-blepharoexfoliation (MBE), intense pulsed light (IPL) and Meibomian gland expression (MGX). Methods An industrial doctoral thesis was performed by compendium of publications. To meet the main objective of the thesis, a controlled clinical trial was performed. Previously, the safety and efficacy of MBE, light therapies and MGX were systematically reviewed. Subsequently, a longitudinal study was performed to determine the intraobserver repeatability of the S390L Firefly WDR slit lamp used in the measurement of the variables analyzed in the controlled clinical trial. Results The combined treatment of MBE-IPL-MGX obtained significantly superior results compared to home-based therapy in those variables related to dry eye symptoms, as well as tear film stability, Meibomian gland morphology and secretion. In addition, the improvement in Meibomian gland secretion score (MGYSS) was significantly higher in MGD grades 2 and 3. In terms of safety, 18.3 ± 10.1% adverse effects (AEs) were reported. Regarding systematic reviews, MBE achieved a greater reduction in symptoms and signs than home-based therapy, as well as greater meibum delivery. Light therapies showed similar results, highlighting the improvement of meibum quality. However, MGX combined with home-based therapy only showed significant results in symptoms reduction. Concerning safety, MBE presented 2.4% of AEs events, while light therapies did not generate AEs. However, the AEs of MGX could not be analyzed due to the lack of data in the reviewed studies. Referring to the S390L Firefly WDR slit lam

Next-generation light-emitting applications such as displays and optical communications require judicious control over emitted light, including intensity and angular dispersion. To date, this remains a challenge as conventional methods require cumbersome optics. Here, we report highly directional and enhanced electroluminescence from a solution-processed quasi-2-dimensional halide perovskite light-emitting diode by building a device architecture to exploit hybrid plasmonic-photonic Tamm plasmon modes. By exploiting the processing and bandgap tunability of the halide perovskite device layers, we construct the device stack to optimise both optical and charge-injection properties, leading to narrow forward electroluminescence with an angular full-width half-maximum of 36.6° compared with the conventional isotropic control device of 143.9°, and narrow electroluminescence spectral full-width half-maximum of 12.1 nm. The device design is versatile and tunable to work with emission lines covering the visible spectrum with desired directionality, thus providing a promising route to modular, inexpensive, and directional operating light-emitting devices.

A new procedure for the bioactivation of alumina-based porous ceramic constructs was introduced. The constructs were built with the aim of mimicking the structural and mechanical properties of the human cortical bone. Bioactivation was achieved by adding wollastonite and acidic surface treatment (piranha solution). Structural studies (SEM, CAT) confirmed that adequate pore size and interconnectivity were obtained. Uniaxial compression tests showed that the values of Young's moduli and compressive strength were reduced, from 5 to 1 GPa, and from 45 to 15 MPa, respectively, as the wollastonite content increased from 0 to 40 wt.%. Proliferative, histological and fluorescence results confirmed that cell proliferation rate of bone-marrow-derived mesenchymal stem cells were significantly enhanced by increasing wollastonite content. No cytotoxic effect was observed. In summary, the fabricated bioceramics exhibited suggestive structural and mechanical properties and they could be useful for the practical bone tissue engineering applications without any adverse biological effects.

La Tesis Doctoral tiene como principal objetivo estudiar y evaluar los distintos enfoques quirúrgicos disponibles actualmente en la corrección del astigmatismo leve en la cirugía implantorrefractivo a través de lente fáquica ICL. En ella se discuten y se enfrentan el manejo incisional, a través de incisiones corneales periféricas relajantes realizadas en el meridiano curvo topográfico, y el implante de lentes tóricas. A su vez, los objetivos secundarios persiguen responder a la pregunta principal de investigación con un mayor rigor científico, dando soporte técnico sobre el análisis vectorial en el reporte de datos de astigmatismo y ahondar en aspectos hasta ahora no tratados en la bibliografía científica en relación al manejo incisional del astigmatismo. En concreto se estudia la arquitectura incisional de la herida corneal provocada por incisiones astigmáticas frente a la incisión quirúrgica principal, así como el efecto astigmáticos de incisiones realizadas con láser de femtosegundo frente a la técnica manual. Las conclusiones generales de la Tesis se pueden resumir en que el manejo de los astigmatismos leves es más eficaz con el implante de lentes tóricas en detrimento del enfoque incisional. Estos resultados están determinados en su mayor parte por la baja reproducibilidad del efecto astigmático generado por las incisiones corneales relajantes.

Background: Dry eye disease (DED), a prevalent condition with a multifactorial etiology, significantly impacts global health by causing discomfort and visual disturbance. This historical cohort study evaluates the efficacy of Intense Pulsed Light (IPL) therapy on meibomian gland dysfunction (MGD)-related evaporative DED. Methods: The study involved 110 patients (220 eyes) who underwent IPL therapy. Ethical approval was secured, and informed consent was obtained from all participants. A Tearcheck® (ESWvision, Houdan, France) device was used for ocular surface evaluation, measuring tear film stability (NIFBUT, NIABUT), tear film quantity (CTMH, TTMH), and inflammation (OSIE). The study assessed tear film and ocular surface health across multiple IPL sessions. Results: Significant improvements were observed in subjective symptoms (EFT score increased from 29.10 ± 8.87 to 35.91 ± 7.03, p < 0.01), tear film stability (NIFBUT increased from 9.37 ± 6.04 to 10.78 ± 5.83 s, p < 0.01; NIABUT increased from 11.07 ± 4.98 to 12.34 ± 4.66 s, p < 0.01), and tear film surface evaluation (TFSE score decreased from 337.78 ± 414.08 to 206.02 ± 240.44, p < 0.01). Tear film quantity remained unchanged (CTMH and TTMH, p > 0.05). Conclusions: IPL therapy is a promising treatment for DED, improving symptoms and ocular surface health. Further research is warranted to explore long-term efficacy and optimization.

Direct Laser Writing (DLW) has been increasingly selected as a microfabrication route for efficient, cost-effective, high-resolution material synthesis and conversion. Concurrently, lasers participate in the patterning and assembly of functional geometries in several fields of application, of which electronics stand out. In this review, recent advances and strategies based on DLW for electronics microfabrication are surveyed and outlined, based on laser material growth strategies. First, the main DLW parameters influencing material synthesis and transformation mechanisms are summarized, aimed at selective, tailored writing of conductive and semiconducting materials. Additive and transformative DLW processing mechanisms are discussed, to open space to explore several categories of materials directly synthesized or transformed for electronics microfabrication. These include metallic conductors, metal oxides, transition metal chalcogenides and carbides, laser-induced graphene, and their mixtures. By accessing a wide range of material types, DLW-based electronic applications are explored, including processing components, energy harvesting and storage, sensing, and bioelectronics. The expanded capability of lasers to participate in multiple fabrication steps at different implementation levels, from material engineering to device processing, indicates their future applicability to next-generation electronics, where more accessible, green microfabrication approaches integrate lasers as comprehensive tools.

One important issue associated to magnetocaloric materials that hinders its technological application is the poor processability and structural integrity of those with the highest performance, usually intermetallics undergoing first-order magnetic phase transitions. Additionally, the performance of these magnetocaloric materials highly depends on the structural stability of the magnetocaloric phase, which is, in many cases, very sensitive to temperature and mechanical processes. Additive manufacturing via the extrusion of polymer-based composites is regarded as a promising way to overcome these issues. A recently presented manufacturing method of encapsulating functional fillers into polymer capsules has been used to produce a composite filament with a large load of magnetocaloric off-stoichiometric Ni2MnGa Heusler alloy fillers with a uniform distribution throughout the polymer matrix as demonstrated by x-ray tomography characterization. The incorporation of these metallic particles causes changes in the thermal behavior of the polymer as well as an increase in the flowability of the composite with respect to the polymer at the same temperature. The increased flowability of the composites found during manufacturing can be compensated by lowering the extrusion temperatures, making this technique even more convenient for preserving the filler properties, which is an important concern when additive manufacturing magnetocaloric materials. This is confirmed by the magnetic and magnetocaloric behavior of the composites, with responses proportional to the fraction of fillers.

Se analiza el problema de los horarios y la hora legal en España.

A short take on the pros and cons associated with daylight saving time

Se describe la utilidad del cambio de hora

Purpose. To determine the relationship between dyslipidemia and dry eye disease (DED), as well as its influence on tear 6lm and meibomian glands. Methods. ,is cross-sectional study included 40 patients with a mean age of 35.2 ± 13.9 years without any history of dyslipidemia. DED and serum lipid profile were evaluated after 8 hours of fasting. Patients were classified according to serum lipid levels with the following cut-off values: total cholesterol (TC) (200 mg/dl), high-density lipoprotein (HDL) (40 mg/dl), low-density lipoprotein (LDL) (130 mg/dl), and triglycerides (TG) (150 mg/dl). The relationship between serum lipid levels and DED was analyzed with the following variables: dry eye questionnaire-5 (DEQ-5), 6rst (F-NIBUT) and average (A-NIBUT) noninvasive breakup time, tear meniscus height (TMH), lipid layer grade (LLG), conjunctival bulbar redness (CBR), and upper (U-LAMG) and lower (L-LAMG) loss area of meibomian glands. Results. Regarding tear 6lm, patients with elevated TC and LDL levels reported significantly higher DEQ-5 scores and TMH (P < 0.05), while those with lower HDL levels showed significantly higher LLG (p < 0.05). Regarding MGD, patients with elevated TC, LDL, and TG, as well as lower HDL levels showed significantly higher L-LAMG (p < 0.05). HDL was correlated with LLG (p < 0.05), while TC was correlated with TMH (p < 0.05) and L-LAMG (p < 0.05), respectively. Conclusions. Disorders in TC, HDL, LDL, and TG levels were associated with DED, having an impact on the tear film and meibomian glands, specifically in DEQ-5 scores, LLG, and L-LAMG.

Introduction: Lid-parallel conjunctival folds (LIPCOF) and conjunctivochalasis (CCH) are similar conditions that seem to be related to dry eye severity. In addition, there is a lack of studies on the topic of LIPCOF and CCH on dry eye symptoms in non-contact lens and contact lens (CL) wearers. Therefore, the aim of this study is to review the relationship of LIPCOF and CCH with dry eye symptoms in non-CL and CL wearers, as well as to report the treatment of dry eye disease (DED) in non-CL and CL wearers who present LIPCOF or CCH. Methods: A literature review of full-length original studies in two databases, PubMed and Scopus, was performed. The search period included observational studies in humans published between April 21, 2009 and March 20, 2023. Results: A total of 26 studies were included. The studies suggest that LIPCOF and CCH are significantly related to dry eye symptoms in non-CL and CL wearers. However, the impact of CL wear on LIPCOF and CCH may be complex and may vary depending on individual factors such as lens type, lens care regimen, and pre-existing ocular conditions. Regarding LIPCOF management, tear substitutes seem to significantly reduce LIPCOF and dry eye symptoms in non-CL wearers, while vectored thermal pulsation (VTP) and microblepharoexfoliation (MBE) are suggested as promising treatment for LIPCOF and dry eye symptoms in CL wearers. Regarding CCH management, surgical interventions may be effective in reducing CCH when medical treatments have no response. In addition, an ocular examination by slit lamp is necessary to distinguish both conditions. Conclusions: Tear substitutes, VTP, MBE, and fitting CLs with low coefficient of friction (CoF) seem to reduce and prevent LIPCOF. However, surgical treatment options seem to be more effective in the complete elimination of CCH. An adequate evaluation and differentiation between LIPCOF and CCH are important, and they should be considered by practitioners in managing dry eye symptoms in non-CL and C

The efficiency and reliability of perovskite solar cells have rapidly increased in conjunction with the proposition of advanced single-junction and multi-junction designs that allow light harvesting to be maximized. However, Sn-based compositions required for optimized all-perovskite tandem devices have reduced absorption coefficients, as opposed to pure Pb perovskites. To overcome this, we investigate near- and far-field plasmonic effects to locally enhance the light absorption of infrared photons. Through optimization of the metal type, particle size, and volume concentration, we maximize effective light harvesting while minimizing parasitic absorption in all-perovskite tandem devices. Interestingly, incorporating 240 nm silver particles into the Pb-Sn perovskite layer with a volume concentration of 3.1% indicates an absolute power conversion efficiency enhancement of 2% in the tandem system. We present a promising avenue for experimentalists to realize ultrathin all-perovskite tandem devices with optimized charge carrier collection, diminishing the weight and the use of Pb.

The interplay between adiabatic cooling and isothermal ordering is analyzed to rebut the proof of the equivalence of the Nernst theorem and the heat capacity statement of the third law presented by Su and Chen., Se analiza la conexión entre el enfriamiento adiabático y la ordenación isoterma para refutar la demostración de la equivalencia del teorema de Nernst y el enunciado de la capacidad calorı́fica del tercer principio de la termodinámica presentado por Su y Chen.

Purpose: To review the rebound effect after cessation of different myopia control treatments. Methods: A systematic review that included full-length randomised controlled studies (RCTs), as well as post-hoc analyses of RCTs reporting new findings on myopia control treatments rebound effect in two databases, PubMed and Web of Science, was performed according to the PRISMA statement. The search period was between 15 June 2023 and 30 June 2023. The Cochrane risk of bias tool was used to analyse the quality of the selected studies. Results: A total of 11 studies were included in this systematic review. Unifying the rebound effects of all myopia control treatments, the mean rebound effect for axial length (AL) and spherical equivalent refraction (SER) were 0.10 ± 0.07 mm [−0.02 to 0.22] and −0.27 ± 0.2 D [−0.71 to −0.03] after 10.2 ± 7.4 months of washout, respectively. In addition, spectacles with highly aspherical lenslets or defocus incorporated multiple segments technology, soft multifocal contact lenses and orthokeratology showed lower rebound effects compared with atropine and low-level light therapy, with a mean rebound effect for AL and SER of 0.04 ± 0.04 mm [0 to 0.08] and −0.13 ± 0.07 D [−0.05 to −0.2], respectively. Conclusions: It appears that the different treatments for myopia control produce a rebound effect after their cessation. Specifically, optical treatments seem to produce less rebound effect than pharmacological or light therapies. However, more studies are required to confirm these results.

Background/Objectives: Presbyopia, a common age-related refractive error, affects over a billion people globally and significantly impacts daily life. Methods: This retrospective study analyzed 288 eyes of 144 patients undergoing LBV PRESBYOND® treatment for myopic presbyopia with astigmatism, aiming to evaluate precision, efficacy, safety, and stability over six months. Results: Key findings include high efficacy, with 99% of distance-eyes achieving uncorrected distance visual acuity (UDVA) of 20/25 or better, and 85% of near-eyes achieving UDVA of 20/32 or better. The results show excellent refractive outcomes, with 99% of long-sighted eyes and 97% of near-sighted eyes having a postoperative spherical equivalent within ±1.00 D. Safety was demonstrated by no loss of two or more Snellen lines after treatment, with 94% of patients maintaining corrected distance visual acuity (CDVA) before and after surgery. Conclusions: Overall, LBV PRESBYOND® proved effective, safe, and well tolerated for myopic presbyopia correction, offering satisfactory visual outcomes and potential spectacle independence for various distances. This study underscores the importance of individualized treatment based on patient age, highlighting the positive impact of binocular summation on visual function. This study contributes to the growing body of evidence supporting LBV PRESBYOND® as a viable option for addressing presbyopic myopia, offering insights into its efficacy and safety profile. Further research could explore postoperative stereopsis and long-term outcomes to enhance understanding and refine treatment protocols.

In this work, the influence of the aspect ratio of graphene-based nanostructures (GBNs) and content on the mechanical properties of 3 mol% yttria tetragonal zirconia polycrystalline 3Y-TZP matrix composites was analysed. The influence of the dispersion method and sintering parameters on the flexural strength and elastic modulus of the composites was studied, and the fracture surfaces were characterized to determine the fracture mechanisms that occur. The results showed that small amounts of exfoliated graphene nanoplatelets, with reduced lateral size, and few layer graphene, up to 1.0 and 2.5 vol%, respectively, slightly increase the 3Y-TZP flexural strength. This has been attributed to the tortuosity of the crack propagation pathways and strengthening mechanisms. Higher contents cause a decrease in flexural strength and stiffness because of overlapped GBNs, which can promote the crack propagation. The pull-out of GBN was more significant in composites with non-exfoliated graphene nanoplatelets, where no increase on the flexural or biaxial strength was measured.

Background: Macular pigment in retina is formed by lutein and zeaxanthin. These carotenoids must be ingested. Fruit, vegetables, and eggs are rich in lutein and zeaxanthin. In adults, there are many factors that increase macular pigment values, although not enough studies have been performed in children. Objective: The main aim of this study was to analyze macular pigment in children considering healthy habits and exposure to LEDs screens. Methods: A cross-sectional, observational study was conducted, recruiting 27 children aged 7–13 years. Healthy habits, demographic data and exposure to LEDs were analyzed using a questionnaire. To study adherence to the Mediterranean diet, the validated KIDMED questionnaire was used. Macular pigment optical density was measured using Heterochromatic Flicker Photometry, and weight and height were also recorded and expressed by body mass index. Results: The mean MPOD value was 0.45 ± 0.14. BMI percentile was studied in the children, with most of them presenting normal weight (55.55 %). Regarding the KIDMED questionnaire, ingesting a fruit or fruit juice every day increases macular pigment optical density (0.47 ± 0.13 vs 0.24 ± 0.07, p = 0.034). No correlation was found for the KIDMED questionnaire score, BMI or age with MPOD value. Conclusion: Lutein and zeaxanthin intake, as well as healthy habits, increase MPOD value. However, no relation was found for several of the factors evaluated with MPOD value.

This paper deals with the effect of hydroxylated boron nitride nanosheets (BNNS) incorporation on the microstructural and mechanical features of zirconia ceramics. Few-layered BNNS were synthesized via a simple hydroxide-assisted planetary ball milling exfoliation technique. 3 mol% yttria tetragonal zirconia polycrystal (3Y-TZP) with 2.5 vol% BNNS powders were prepared by an environmentally friendly process in water, and spark-plasma sintered at three temperatures to explore the in-situ reduction of the functionalized BNNS. An exhaustive study by (S)TEM techniques was performed to elucidate the influence of the sintering temperature on the matrix and the 3Y-TZP/BNNS interfaces, revealing that BNNS were homogeneously distributed throughout the matrix with an abrupt transition at 3Y-TZP/BNNS interfaces. BNNS effectively hindered slow crack growth, thus increasing the composite's crack growth resistance by about 30 %. A 1 MPa·m1/2 rising R-curve was also induced by crack bridging.

Introduction: To assess the efficacy and safety of the combination of microblepharoexfoliation (MBE), intense pulse light (IPL) and meibomian gland expression (MGX) for treatment of meibomian gland dysfunction (MGD). Methods: This was a prospective, parallel-control trial conducted from April 2022 to January 2023. Participants were assigned to receive either three sessions of MBE-IPL-MGX treatment and home-based therapy (treatment group) or home-based therapy alone (control group). Outcome measures were assessed at baseline and after 2-month follow-up. Results: Seventy eyes of 70 patients were enrolled. MBE-IPL-MGX treatment achieved better improvements than home-based therapy in ocular surface disease index (OSDI) and symptom assessment in dry eye (SANDE) scores, noninvasive tear film break-up time (NIBUT), lipid layer grade (LLG), loss area meibomian gland (LAMG) and meibomian gland yielding secretion score (MGYSS). The mean differences between the two groups were as follows: OSDI (– 11.23 ± 4.68 points, P \0.001), SANDE (– 24.63 ± 13.41 points, P \0.001), NIBUT (1.3 ± 1.57 s, P = 0.033), LLG (0.4 ± 0.04 points, P = 0.003), LAMG (– 2.85 ± 1.69%, P = 0.023) and MGYSS (7.5 ± 2.32 points, P \ 0.001). In addition, the increment (D) of MGYSS after MBE-IPL-MGX treatment was significantly higher in MGD grades 2 and 3 (all P \ 0.001). Conclusions: MBE-IPL-MGX treatment is an effective and well-tolerated procedure that improves dry eye symptoms and signs as well as meibomian gland secretions in patients with MGD. In addition, this treatment is recommended for MGD grades 2 and 3.

Purpose: To compare the effectiveness of meibomian gland expression (MGX) combined with home-based therapy versus home-based therapy alone for the treatment of dry eye disease (DED) caused by meibomian gland dysfunction (MGD). Methods: A systematic review of randomized controlled studies (RCTs), reporting the effects of MGX combined with home-based therapy in 2 databases, PubMed and Web of Science, was performed according to the PRISMA statement. The search period was until August 20, 2023. According to the heterogeneity, a random or fixed effects model was performed in the meta-analysis. The standardized mean difference (SMD) was calculated to analyze dry eye symptoms (DES) score, tear film break-up time (TBUT), total corneal fluorescein staining (tCFS) and meibomian glands expressibility (MGE). All analyses were performed by RevMan Web, version 5.7. The Cochrane risk of bias tool was used to analyze the quality of the studies selected. Results: Two RCTs with a total of 99 patients were included. The studies reported that MGX combined with home-based therapy improves DES score, TBUT, tCFS and MGE compared to the home-based therapy. However, the meta-analysis indicated that MGX combined with home-based therapy only seems to be beneficial in reducing DES score (SMD -0.49; 95 % CI: -0.89 to -0.08; P = 0.02; I2 = 0 %). In addition, although TBUT, tCFS and MGE reported a slight trend in favor of MGX combined with home-based therapy, it was non-significant. Conclusions: While MGX combined with home-based therapy seem to show some evidence of alleviating dry eye symptoms, there is insufficient evidence to conclude the effects of this treatment definitively particularly in improving dry eye signs caused by MGD, such as TBUT, tCFS and MGE. Therefore, further RCTs are needed to elucidate these results.

Introduction: To evaluate the efficacy and safety of Quantum Molecular Resonance (QMR) treatment in patients with severe dry eye disease (DED), as well as its effects on aqueous-deficient (ADDE), evaporative (EDE), and mixed (MDE) dry eye. Methods: In this prospective, interventional study, 81 patients were randomly allocated to received four treatment sessions of QMR at 1-week intervals (Rexon-Eye®, Resono Ophthalmic, Trieste, Italy) (QRM group) or tear substitute four times daily, containing 0.15% sodium hyaluronate and 3% trehalose (Thealoz Duo®, Thea Pharma, France) (SH-TH group). Outcome measures included ocular surface disease index (OSDI) questionnaire, tear meniscus height (TMH), tear breakup time (TBUT), non-invasive breakup time (NIBUT), corneal fluorescein staining (CFS), lipid layer thickness (LLT), tear film osmolarity (OSM), and meibomian gland dysfunction (MGD) grade, which were assessed at baseline and 1-month and 3-month follow-up. Results: The QMR group achieved better improvements than the SH-TH group in OSDI and SANDE questionnaires, NIBUT, LLT, and CFS. The mean differences between the groups were as follows: OSDI (− 12.4 ± 0.25 points, P = 0.01), SANDE (10.6 ± 1.7 points, P = 0.01), NIBUT (2 ± 0.25 s, P = 0.01), LLT (18.7 ± 0.7 nm, P = 0.01), and CFS (1.2 ± 0.1 points, P = 0.02). In subgroups analysis, QMR treatment demonstrated a beneficial role to improve DED symptoms and signs in ADDE, EDE, and MDE. Conclusion: QMR is an effective and well-tolerated treatment that seems to improve DED symptoms and signs in patients with severe DED. However, further studies are needed to confirm this. Trial Registration: ClinicalTrials.gov identifier NCT06119386.

Amorphous precursors with the composition MnCo0.8Fe0.2Ge1-xSix, where x = 0.2, 0.3, 0.4, and 0.6, were obtained through mechanical alloying. These precursors were subsequently subjected to different thermal treatments, resulting in the formation of the austenite Ni2In-type structure for x ≤ 0.4. For the highest Si content (x = 0.6), this phase coexists with the martensite TiNiSi-type structure without apparent partitioning of the elements at the nanoscale. These structures remain stable up to their melting points, but subsequent melting processes exhibit differences compared to the initial solidification at a cooling rate of − 20 K/min. The magnetocaloric effect was investigated through thermomagnetic and heat capacity measurements and simulated using the Arrott-Noakes equation of state, revealing the presence of a distribution of Curie temperatures. Despite the absence of a martensitic transformation, these alloys exhibit a significant magnetocaloric response, which increases as the precursor system's amorphization (i.e., homogenization) is enhanced.

In this study, Cu-doped ZnO aerogel nanoparticles with a 4% copper concentration (Cu4ZO) were synthesized using a sol–gel method, followed by supercritical drying and heat treatment. The subsequent fabrication of Cu4ZO ceramics through Spark Plasma Sintering (SPS) was characterized by X-ray diffraction (XRD), field-emission gun scanning electron microscopy (FE-SEM) equipped with EDS, and impedance spectroscopy (IS) across a frequency range of 100 Hz to 1 MHz and temperatures from 270 K to 370 K. The SPS–Cu4ZO sample exhibited a hexagonal wurtzite structure with an average crystallite size of approximately 229 ± 10 nm, showcasing a compact structure with discernible pores. The EDS spectrum indicates the presence of the base elements zinc and oxygen with copper like the dopant element. Remarkably, the material displayed distinct electrical properties, featuring high activation energy values of about 0.269 ± 0.021 eV. Complex impedance spectroscopy revealed the impact of temperature on electrical relaxation phenomena, with the Nyquist plot indicating semicircular arc patterns associated with grain boundaries. As temperature increased, a noticeable reduction in the radius of these arcs occurred, coupled with a shift in their center points toward the axis center, suggesting a non-Debye-type relaxation mechanism. Dielectric analyses revealed a temperature-driven evolution of losses, emphasizing the material’s conductivity impact. Non-Debye-type behavior, linked to ion diffusion, sheds light on charge storage dynamics. These insights advance potential applications in electronic devices and energy storage.

Purpose: To characterize microbial keratitis diversity utilizing species richness and Shannon Diversity Index. Methods: Corneal impression membrane was used to collect samples. All swabs were processed and analyzed by Biolab Laboratory (level V—SSN Excellence: ISO 9001:2015), Biolab Srl (Ascoli Piceno, Italy). DNA extraction, library preparation, and sequencing were performed in all samples. After sequencing, low-quality and polyclonal sequences were filtered out by the Ion software. At this point, we employed Kraken2 for microbial community analysis in keratitis samples. Nuclease-free water and all the reagents included in the experiment were used as a negative control. The primary outcome was the reduction in bacterial DNA (microbial load) at T1, expressed as a percentage of the baseline value (T0). Richness and Shannon alpha diversity metrics, along with Bray–Curtis beta diversity values, were calculated using the phyloseq package in R. Principal coordinate analysis was also conducted to interpret these metrics. Results: 19 samples were included in the study. The results exhibited a motley species richness, with the highest recorded value surpassing 800 species. Most of the samples displayed richness values ranging broadly from under 200 to around 600, indicating considerable variability in species count among the keratitis samples. Conclusions: A significant presence of both typical and atypical bacterial phyla in keratitis infections, underlining the complexity of the disease’s microbial etiology.

Field-assisted sintering techniques are at the forefront of advanced energy-saving procedures to create fully dense ceramic materials. At present, there is an extraordinary interest in understanding the sintering process and effectively controlling the final specimen’s microstructure. This latter aspect is critical, but unfortunately, the short sintering times and intense electric fields under non-equilibrium conditions prevent a rigorous prediction in most cases. This paper is a theoretical contribution to gain insight into an outstanding effect of applying intense electric fields: the formation of non-spherical grain structures. A phase field simulation approach has been carried out to reproduce and determine the origin of this effect. The final simulated microstructures are proved to be textured. These results are explained in the framework of a recent model and compared with experimental evidence reported in the literature.

Purpose: To assess which signs and eye prosthesis care habits are related to subjective discomfort in patients with dry anophthalmic socket syndrome (DASS), using standardized tools from daily practice. Methods: 62 anophthalmic sockets were compared with their healthy fellow eye using the Standard Patient Evaluation of Eye Dryness (SPEED) score. The correlations between SPEED questionnaire and the prosthesis care, discharge characteristics score, conjunctival inflammation score, meibomian gland dysfunction (MGD) scores and Schirmer I test were studied. Result: The anophthalmic sockets group achieved a higher SPEED test score (p < 0.01), discharge score (p < 0.01), conjunctival inflammation score (p < 0.01), MGD scores (p < 0.01) and lower Schirmer I test (p < 0.01) compared with their fellow, healthy eye. Patients with a prosthesis replacement of one year or less, those with a current fit time of one year or less and those with a cleaning frequency above one month reported better SPEED, (p < 0.01), conjunctiva inflammation (p < 0.01) and MGD scores (p < 0.01). Conclusion: Most anophthalmic patients suffer mild to severe DASS, which seems related to discharge, conjunctival inflammation and MGD. Moreover, certain practices related to the care of the prosthesis such as replacing with a frequency lower than yearly, current fitting time inferior to one year and a removing and cleaning regime above one month, were related to a lower discomfort sensation, conjunctival inflammation and MGD. Clinicians should consider the DASS when facing patients with anophthalmic socket and discomfort symptoms.

We study the phase transition behavior of the ferroelectric BaTi0.8Zr0.2O3 in the paraelectric region. The temperature dependencies of thermal, polar, elastic and dielectric properties indicate the presence of local structures above the paraelectric-ferroelectric transition temperature Tc = 292 K. The non-zero remnant polarization is measured up to a characteristic temperature T* ~350 K, which coincides with the temperature where the dielectric constant deviates from Curie-Weiss law. Resonant Piezoelectric Spectroscopy shows that DC field-cooling above Tc using fields smaller than the coercive field leads to an elastic response and remnant piezoelectricity below T*, which likely corresponds to the coherence temperature associated with polar nanostructures in ferroelectrics. The observed remnant effect is attributed to the reorientation of polar nanostructures above Tc.

This study evaluated the effectiveness of hyaluronic acid and trehalose (HA/trehalose) eyedrops in managing dry eye disease (DED) symptoms by measuring tear stability and administering a DED questionnaire. Sixty patients were treated with either HA/trehalose eyedrops (Tear A) or carmellose sodium eyedrops (Tear B) as controls. The tear breakup time (TBUT) and non-invasive breakup time (NIBUT) were monitored, and patients completed the standard patient evaluation of eye dryness (SPEED) questionnaire. After two months of twice-daily applications, patients treated with the HA/trehalose eyedrops demonstrated significant improvements in the NIBUT (12.98 ± 3.22 s) and TBUT (12.95 ± 2.98 s), indicating increased tear stability. Moreover, they reported lower dry eye sensation (6.70 ± 4.94 SPEED score points), suggesting a reduction in DED symptoms. These findings underscore the efficacy of HA/trehalose eyedrops in improving both the objective and subjective signs of DED, with twice-daily application enhancing ocular surface conditions and reducing patient-reported symptoms. © 2023 by the authors.

En este trabajo introduciremos la física de agujeros negros a través de las predicciones de la Relatividad General. Además, se repasarán algunos resultados obtenidos por la Event Horizon Telescope Collaboration sobre los estudios de la fuente de radiación emitida en el núcleo de la galaxia M87. Por ello, comenzaremos introduciendo la Relatividad General y las ecuaciones de Einstein, aportando algunas propiedades que se deducen de ellas. Tras esto, expondremos las principales soluciones de agujeros negros: Schwarzschild, Reissner-Nordström y Kerr. Estudiaremos la estructura causal de estas soluciones, además de algunas propiedades geométricas importantes. Finalmente, se realiza un resumen de los resultados obtenidos al estudiar la imagen del agujero negro de la galaxia M87., In this work we introduce black hole physics through the predictions of General Relativity. Moreover, we expose some results of the Event Horizon Telescope Collaboration about the radio source emitted by the core of the galaxy M87. Thus, we start introducing General Relativity and Einstein´s field equations, giving some properties deduced by them. After this, we show the main solutions of black holes: Schwarzschild, Reissner-Nordström and Kerr. We study the causal structure of these solutions and some important geometrical properties. Finally, we make a review about the results obtained from the image of galaxy M87

En este Trabajo de Fin de Grado se estudia la impresión 3D por estereolitografía modificando la resina comercial Elegoo Mars con distintas fracciones de carga sólida de sílice AEROSIL OX50. Primero se explican los fundamentos de la impresión 3D y de la estereolitografía y del sólido utilizado. A continuación, se realizan experimentos para conocer la distribución de tamaño de partículas, la isoterma de adsorción y la superficie específica de la sílice comercial empleada. Posteriormente, se llevan a cabo la impresión 3D de las piezas de interés con diferentes composiciones de resina y sílice, un estudio de la profundidad de curado, un análisis por espectrometría UV-Vis, una caracterización reológica, un proceso de pirólisis y observaciones por SEM y Tomografía. Los resultados obtenidos ponen de manifiesto el interés científico de modificar resinas con cargas en sólido para la impresión 3D.

Este documento se centra en la temática de los sistemas autoorganizados, aquellos que presentan propiedades emergentes a partir de la interacción entre sus componentes individuales sin necesidad de una interacción externa. Se presenta el modelo de Kuramoto y su aplicación en el desarrollo de modelos autoorganizativos más complejos, como el "Swarmalator". Este modelo es especialmente útil para estudiar fenómenos biológicos y sociales que implican comportamiento colectivo y movilidad espacial. Además, se pone de manifiesto la importancia de la modelización numérica en el estudio de los sistemas autoorganizados, y se usa el lenguaje de programación Python como lenguaje actual, potente y versátil. Se sabe que la simulación computacional es una herramienta valiosa para el estudio de los sistemas autoorganizados, ya que permite explorar diferentes escenarios y analizar como cambian las propiedades emergentes del sistema a medida que cambian las condiciones iniciales o los valores de los parámetros del modelo. En particular, se discute cómo los modelos numéricos pueden ser utilizados para simular fenómenos complejos como la formación de patrones en células o el comportamiento colectivo en animales. Estos modelos pueden proporcionar información valiosa sobre como surgen las estructuras complejas a partir de interacciones simples.

El panorama energético mundial actual exige la investigación y el desarrollo de sistemas de almacenamiento de energía eficientes. El supercondensador de doble capa o EDLC (Electrochemical Double Layer Capacitor) es un tipo de dispositivo de almacenamiento de energía cuyo estudio resulta de gran interés debido a sus propiedades electroquímicas. Además de la elevada capacidad de carga que este posee, del orden de entre 1F y 100F, la ausencia de procesos farádicos en su interior le confiere un largo ciclo de vida. La capacidad de almacenamiento de carga de estos dispositivos se debe principalmente a la composición de sus electrodos, en los que se emplea carbón activado, un material con una elevada porosidad, que aumenta considerablemente el área superficial en la que puede almacenarse la carga. Además, el almacenamiento de carga se produce en una doble capa electrostática, en ausencia de procesos farádicos, lo cual confiere al dispositivo un largo ciclo de vida. En este trabajo se ha fabricado un supercondensador de doble capa y posteriormente se han empleado distintas técnicas de análisis electroquímico para estudiar las propiedades de tres supercondensadores diferentes. Mediante las técnicas de carga y descarga galvanostática y voltametría cíclica, se ha estudiado el comportamiento de los dispositivos ante señales en DC aplicando ciclos de carga y descarga, se han obtenido valores de las capacidades, se ha analizado la bondad de cada uno de los dispositivos y se han estudiado sus ciclos de vida. Posteriormente se ha realizado un estudio en AC mediante espectroscopía de impedancia compleja aplicando señales de voltaje sinusoidales a distintas frecuencias. Empleando circuitos sencillos, ha sido posible ajustar los diagramas obtenidos y obtener información a cerca del funcionamiento interno de los supercondensadores.

Este trabajo consiste en el estudio de los diferentes mecanismos de transferencia de calor, para ello utilizaremos un dispositivo no convencional: una cámara termográfica. Con ella podremos estudiar cómo varía la temperatura de un cuerpo que transfiere calor por conducción, convección y radiación; y calcular las magnitudes físicas que caracterizan a cada uno de estos mecanismos: la conductividad térmica, el coeficiente de convección y la emisividad, respectivamente. Para realizar este estudio, una vez hayamos grabado un vídeo de un cuerpo que transfiere calor, compilaremos un código en MATLAB que nos permita realizar dos funciones: primero, importar el vídeo donde observaremos cómo evoluciona el color del cuerpo hasta alcanzar el equilibrio térmico con el entrono y, segundo, relacionar la evolución temporal de la intensidad de los píxeles de la imagen con la evolución de la temperatura del cuerpo. En otras palabras, vamos a construir un termómetro que nos dé la temperatura del cuerpo en cada instante. Todo ello lo realizaremos con dos cuerpos: una pieza metálica que, por lo general, presenta heterogeneidades; y un segundo cuerpo homogéneo obtenido con una impresora 3D. Analizaremos cómo estos dos cuerpos transfieren calor, bien por conducción, cuando están sometidos a un gradiente de temperatura en contacto con una fuente térmica, bien por convección natural o forzada con un ventilador; o bien por ambos mecanismos a la vez. Además, observaremos que, a temperatura ambiente, la radiación es el mecanismo, cuantitativamente, el menos efectivo y, cualitativamente, el más importante. El presente trabajo está estructurado como sigue: En la sección 1 haremos una pequeña introducción teórica sobre los fundamentos de los diferentes mecanismos de transferencia de calor y de la temperatura. En la sección 2 presentaremos los objetivos que se desean estudiar en este trabajo. En las secciones 3 y 4 trataremos el instrumental usado en el laboratorio y el procedimiento experimental

This thesis work is focused on the development of novel multifunctional zirconia composites using two different 2D nanomaterials as fillers, few-layered graphene (FLG) and boron nitride nanosheets (BNNS). BNNS were exfoliated using three different technologies. Eco-responsible powder homogenization routines were evaluated for the dispersion of the nanostructures throughout the ceramic powder and the materials were consolidated using a spark plasma sintering (SPS) furnace. A systematic study of the powder processing and the sintering conditions on the composites with FLG revealed the optimal processing conditions to maximize the FLG crystallinity, which decreases the electrical percolation threshold below 1 vol%. The electrical discharge machinability of the composite with 20 vol% was also analyzed. The addition of the exfoliated BNNS resulted in homogeneous dense composites with submicrometer grain size. The incorporation of partly hydroxylated BNNS revealed the absence of chemical bonding at the zirconia/BN interphase. The scalability of the materials was confirmed in all the different materials. The evaluation of stable crack propagation evidenced rising R-curves only in the materials with larger nanosheets. Reinforcement by bridging of the nanosheets was corroborated although no influence of the reinforcement was detected when measuring the fracture toughness. Finally, since tetragonal stabilized zirconia is sensitive to the presence of water molecules, slow crack growth and hydrothermal aging were analyzed on the composites with either type of nanosheets.

Introducción: El ojo seco es una enfermedad multifactorial que compromete la película lagrimal y la superficie ocular, perjudicando tanto la visión como la comodidad ocular. Entre los factores predisponentes se encuentra ser usuario de lentes de contacto, ya que disrumpen la lágrima provocando los síntomas mencionados anteriormente. Por esta razón, en los últimos años se está investigando posibles soluciones a esta enfermedad, dentro de las cuales destacan el uso de lágrimas artificiales que garanticen a los pacientes un uso cómodo y seguro de las lentes. Objetivo: Determinar la eficacia de la lágrima con aceite ozonizado para tratar el ojo seco en pacientes usuarios de lentes de contacto. Material y métodos: El estudio está compuesto por una muestra de 92 ojos, de los cuales 46 pertenecen al grupo tratado con la lágrima con aceite ozonizado y el resto al grupo tratado con la lágrima que contiene hipromelosa. El estudio se divide en tres etapas A, B, y C, en las cuales se realizan los cuestionarios de ojo seco SPEED y CLDEQ 8, y se analizan varios parámetros oculares relacionados con esta enfermedad mediante un analizador de la superficie ocular. Resultados: Se analizan los resultados de hiperemia conjuntival y del cuestionario SPEED obteniéndose que hay un incremento de la hiperemia en los dos grupos, en el grupo tratamiento aumenta de 1,30 ± 0,59 en la etapa A a 1,59 ± 0,54 en la etapa C, y en el grupo control incrementa de 1,04 ± 0,69 en la primera etapa a 1,31 ± 0,60 en la última. Por otro lado, no hay diferencias entre los grupos en los resultados del cuestionario SPEED, ya que en la etapa A el p valor es de 0,05 y en la etapa C de 0,31. Discusión y conclusiones: La lágrima con aceite ozonizado actúa principalmente como un compuesto antibacteriano, pero no es eficaz en mejorar los síntomas y signos del ojo seco, ya que la hiperemia conjuntival no se ve reducida y los resultados del cuestionario SPEED tampoco se modifican. Aun así, se deberían realizar más estud

Introducción: Durante el desarrollo del ojo, tiene lugar el proceso de emetropización. La descoordinación de este puede originar miopía. La prevalencia de miopía infantil ha aumentado significantemente en los últimos años y, consecuentemente, la prevención y cuidados oculares para controlarla. El primer tratamiento empleado para controlar la miopía fue la atropina, un alcaloide que se une competitivamente a los receptores muscarínicos de acetilcolina, bloqueándolos reversiblemente. Objetivo: El objetivo del presente trabajo fue realizar una revisión sistemática de los estudios con atropina para controlar la miopía infantil en los últimos diez años, así como comparar las concentraciones de atropina empleadas, para determinar cuál se considera más efectiva y segura. Metodología: Esta revisión sistemática se realizó siguiendo las recomendaciones de la guía PRISMA. Para la búsqueda se utilizaron libros de texto, revistas científicas y páginas webs oficiales, así como bases de datos científicas (PubMed, Dialnet y Science Direct). Resultados: Los autores de los artículos analizados obtuvieron resultados estadísticamente significativos (p<0,05) en la reducción de la progresión de la miopía. La mayoría coinciden en que la concentración 0,01% es la más efectiva y segura, con efectos adversos leves (visión borrosa en cerca, fotofobia…etcétera). Aunque el uso de atropina está muy extendido para controlar la miopía, han aparecido nuevas líneas de investigación sobre tratamientos sinérgicos combinados y métodos no farmacológicos más seguros. Conclusiones: Los estudios seleccionados afirman que la atropina frena el crecimiento de la miopía. Sin embargo, existe variabilidad según raza, edad y concentración. Se acepta como la más efectiva y segura una concentración del 0,01%, aunque hay limitaciones como efectos a largo plazo y el efecto rebote, dependiente de la dosis. Cualquiera de los tratamientos debe combinarse con la promoción de hábitos que disminuyan las actividades en cerc

En este trabajo se han caracterizado eléctricamente dos conductores iónicos mediante espectroscopía de impedancia compleja en un rango de temperatura, de manera que en futuros proyectos puedan ser propuestos para ser empleados como electrolitos en Celdas de Combustible de Óxido Sólido (SOFC, por sus siglas en inglés). Por un lado, se ha estudiado una cerámica de circona cúbica dopada con itria al 8% mol. (8YCSZ); y por otro lado, un composite que mantiene esta misma matriz cerámica con una segunda fase de un 1% vol. de nananoláminas de óxido de grafeno reducido (8YCSZ 1rGO), con la finalidad de ver su efecto en la respuesta eléctrica. El composite se ha estudiado en dos configuraciones diferentes. Los datos obtenidos mediante espectroscopía de impedancia se han analizado, y se han obtenido: Los valores de conductividad y energía de activación de los procesos de conducción a través de cada región eléctricamente activa a partir de los valores de los elementos de los circuitos equivalentes (resistencia y capacidad). Estos circuitos se han propuesto para modelar los espectros de impedancia representados mediante diagramas de Nyquist. Los tiempos característicos de los procesos de conducción a través de cada una de las regiones eléctricamente activas mediante tres formalismos: • A partir de los circuitos equivalentes que modelan los diagramas de Nyquist. • Mediante diagramas de Bode, de los que se obtienen las frecuencias características. • Mediante el análisis de las distribuciones de tiempos de relajación. Para el análisis de los diagramas de Nyquist y circuitos equivalentes se ha empleado el software comercial ZView, mientras que para obtener las distribuciones de tiempos de relajación se ha utilizado el software de uso libre DRT tools. Para finalizar, se han expuesto las conclusiones de este trabajo., For this work, two materials that stand out as good ionic conductors have been electrically characterised using complex impedance spectroscopy analysis. The ultimate goal is to propose them for future projects as potential electrolytes in solid oxide fuel cells (SOFCs). On the one hand, a cubic zirconia ceramic doped with 8% mol. yttria (8YCSZ) has been studied. On the other hand, a composite material with the same ceramic matrix and an additional phase of 1% vol. reduced graphene oxide nanosheets (8YCSZ 1rGO) was studied in order to observe the effect of these nanosheets on the electrical response. The composite was studied in two different configurations. The data obtained by impedance spectroscopy were analysed and the following results were obtained: The conductivity values and the activation energy of the conduction processes through each electrically active region were determined from the values of the elements in the equivalent circuits (resistance and capacitance). These circuits were proposed to model the impedance spectra represented by Nyquist plots. The characteristic times of the conduction processes through each electrically active region were determined using three formalisms: • From the equivalent circuits modelling the Nyquist plots. • By analysing the Bode plots to obtain the characteristic frequencies. • By analysing the relaxation time distributions. The commercial software ZView was used for the analysis of the Nyquist plots and the equivalent circuits, while the open source software DRT tools was used to obtain the relaxation time distributions. Finally, the conclusions of this work have been presented.

La miopía es el defecto refractivo ocular con más prevalencia en todo el mundo, afectando principalmente a niños en edad escolar. Por tanto, es necesario reducir su progresión y observar sus diversos factores de riesgo. Las lentes oftálmicas de control de miopía están principalmente orientados a la corrección y control de la miopía. Actualmente actúan sobre la retina provocando un desenfoque periférico hipermetrópico como “MiYosmart” de Hoya y “Stellest” de Essilor, o un desenfoque horizontal como la “Superkid Miofocal” de (Indo). Existen también otros mecanismos de reducción y control de la miopía basados en el control periférico del contraste como la “SightGlass Vision” de Coopervision. El objetivo principal de este trabajo bibliográfico es analizar el diseño y evidencia científica de distintos artículos orientados a lentes oftálmicas para el control de la miopía, comparar el diseño y mecanismo, además de determinar la evidencia científica y eficacia de las lentes oftálmicas. Para ello, la información se ha obtenido a través de 3 bases de datos: Pubmed, Scopus y WOS. De los 7 estudios seleccionados se agruparon los comprendidos entre 2016 y 2023, descartando otro tipo de tratamientos como lentes de contacto o fármacos. Las lentes oftálmicas de control de miopía tienen una eficacia probada del 66% siempre que su uso sea superior a 12 horas. Las evidencias científicas vienen avaladas por 7 estudios durante dos años con 928 pacientes, pero con estos sesgos: estudios aleatorizados, doble ciego y controlados, edades comprendidas entre 6 y 35 años y pacientes de raza asiática. Las nuevas lentes oftálmicas de control de miopía se basan en corregir la miopía y ralentizar la progresión del crecimiento ocular mediante su tratamiento, además de conseguir un adecuado resultado a largo plazo. Se plantean ensayos controlados aleatorizados y un seguimiento postratamiento para evaluar su eficacia., Myopia is the most prevalent ocular refractive defect worldwide, affecting mainly school-age children. Therefore, it is necessary to reduce its progression and observe its various risk factors. Myopia control ophthalmic lenses are mainly oriented to the correction and control of myopia. Currently they act on the retina causing a hypermetropic peripheral defocus as “MiYosmart” from Hoya and “Stellest” from Essilor, or a horizontal defocus as the “Superkid Miofocal” from (Indo). There are also other myopia reduction and control mechanisms based on peripheral contrast control such as Coopervision`s “SightGlass Vision”. The main objective of this bibliographic work is to analyze the design and scientific evidence of different articles on ophthalmic lenses for the control of myopia, to compare the design and mechanism, and to determine the scientific evidence and efficacy of ophthalmic lenses. To do this, the information was obtained from 3 databases: Pubmed, Scopus and WOS. Of the studies selected, those between 2016 and 2023 were grouped, discarding other types of treatments such as contact lenses or drugs. Ophthalmic lenses for myopia control have a proven efficacy of 66% provided they are worn for more than 12 hours. The scientific evidence is supported by 7 studies over two years with 928 patients, but with these biases: randomized, double-masked, controlled studies, ages between 6 and 35 years and Asian patients. New myopia control ophthalmic lenses are based on correcting myopia and slowing the progression of ocular growth by treating myopia and achieving an adequate long-term outcome. Randomized controlled trials and post-treatment follow-up are proposed to evaluate their efficacy.

Las hormonas envían mensajes a varias partes del cuerpo que están diseñadas para recibirlos. Todas las mujeres se ven afectadas por distintos cambios hormonales durante toda su vida que afectan a muchas partes del cuerpo, incluyendo al aparato ocular. Afortunadamente, las alteraciones oculares pueden volver a la normalidad cuando se estabilizan los niveles hormonales. La córnea se ve afectada por las hormonas sexuales, que la modifican a través de los receptores de hormonas femeninas que están localizados en la córnea. Así mismo, puede influir en otras funciones como en la agudeza visual, presión intraocular, cambios de refracción, sequedad ocular, etc. El objetivo principal de este trabajo es la revisión bibliográfica de varios artículos experimentales cuya finalidad es analizar los posibles cambios refractivos y alteraciones oculares y, su relación directa con los cambios hormonales que se producen en las distintas etapas de la vida de la mujer. Para ello se realizó una búsqueda en distintas bases de datos como son Pubmed, Dialnet, Scopus y Scielo. En este trabajo se seleccionaron 17 estudios, los cuales se dividieron según la etapa hormonal en la que se encontraba la mujer. Los resultados de estos artículos nos llevan a la conclusión de que los cambios hormonales influyen en mayor o en menor medida en el aparato ocular de las mujeres, aunque es un tema que necesita ser ampliamente más desarrollado y estudiado.

Las aleaciones de alta entropía (HEAs) se han convertido en una de las líneas de investigación punteras de la ´ultima década gracias su enorme campo composicional. Técnicas de producción de estructuras metaestables, como el aleado mecánico por molienda o el enfriamiento ultrarrápido, pueden dar lugar a soluciones sólidas supersaturadas que permiten extender la formación de HEAs frente a técnicas de producción de aleaciones más convencionales. Esta idea es la que se pretende explorar en este trabajo, sintetizando a partir de una mezcla de elementos puros las aleaciones: CoFeNiCrAl0,75 y CoFeNiMnAl0,75. Para ambas aleaciones, cuyas composiciones y microestructuras se han estudiado en diferentes tiempos de molienda mediante XRF y XRD, se han conseguido formar HEAs, ambas con una fase fcc de comportamiento, a priori, paramagnético a temperatura ambiente (caracterizado mediante espectroscopía Mössbauer y VSM). Se ha estudiado, además, la estabilidad térmica de las HEAs mediante tratamiento en DSC, siendo la HEA de la aleación con Mn térmicamente estable hasta los 640 K, mientras que en el caso de la aleación con Cr se tiene una transición mucho más suave que pudiera ser indicativa de la existencia de una fase bcc. Un problema que ha aparecido durante la molienda, realizada en molino planetario de bolas, ha sido la adhesión de ambas muestras a las bolas y paredes de los viales debido a la ductilidad de los elementos usados. Esto ha permitido estudiar el uso del B como abrasivo para desprender las muestras y ver su efecto en la estructura de estas, añadiendo al estudio las aleaciones de CoFeNiCrAl0,75B1,55 y CoFeNiMnAl0,75B1,3, que también se han caracterizado composicional, microstructural, térmica y magnéticamente. Además, con la adición de B a la composición, se ha podido concluir que la entropía configuracional no es la única contribución relevante en la formación de HEAs pues, pese al aumento de la entropía configuracional de la composición, aparecen varias fases y, p, High entropy alloys (HEAs) have become a prominent area of research in the past decade due to their extensive compositional range. Techniques like mechanical alloying through milling or ultrafast cooling enable the production of metastable structures and they can result in supersaturated solid solutions that extend the formation of HEAs beyond more conventional alloy production techniques. In this work, we aim to explore this idea by synthesizing two alloys: CoFeNiCrAl0,75 and CoFeNiMnAl0,75, from a mixture of pure elements. For both alloys, we have studied their compositions and microstructures at different milling times using XRF and XRD analysis. As a result, we have successfully formed HEAs characterized by an fcc phase. These HEAs demonstrate, a priori, paramagnetic behavior at room temperature, as determined by M¨ossbauer and VSM spectroscopy. The thermal stability of the HEAs was also studied via DSC treatment. The Mn HEA displayed thermal stability up to 640 K, whereas the Cr HEA exhibited a much smoother transition, which could be indicative of the presence of a bcc phase. During the milling process, conducted in a planetary ball mill, a challenge arose due to the adhesion of both samples to the balls and vials walls, which can be attributed to the ductility of the elements used. This has provided an opportunity to study the use of B as an abrasive to detach the samples and observe its effect on their structure. As part of the study, we have also characterized the alloys: CoFeNiCrAl0,75B1,55 and CoFeNiMnAl0,75B1,3, examining their composition, microstructure, thermal behaviour and magnetic properties. Furthermore, the addition of B to the composition has allowed us to conclude that the configurational entropy is not the only significant factor in HEAs formation. Despite the increase in configurational entropy resulting from the B addition, the presence of multiple phases indicates the destruction of the obtained HEAs.

En cuanto a salud visual, una de las principales causas de ceguera en los países desarrollados es la degeneración macular asociada a la edad (DMAE). Esta patología afecta a mayores de 50 años. Como consecuencia del estrés oxidativo se producen cambios morfológicos indeseados en la retina, con acúmulos de desechos (drusas), que afectan a la visión. Esta enfermedad representa un grave problema sanitario debido a que no existe hoy en día un tratamiento eficaz para su cura. El estudio de los distintos factores que pueden influir en la aparición y evolución de la enfermedad favorece la aplicación de medidas preventivas. Del mismo modo, el análisis de los suplementos indicados con fines preventivos para la DMAE facilita un mejor conocimiento de los mismos y la correcta elección para cada uno de ellos, en función de las características nutricionales de cada paciente. En este trabajo se realiza el análisis de los fármacos del mercado español que poseen luteína (Lu) y zeaxantina (Ze) en su composición, ya que hay estudios previos en los que se muestra el poder antioxidante de estos dos carotenoides a nivel retiniano. Además de estudiar la composición de estos suplementos, se evalúan las evidencias científicas de cada uno de ellos. De esta forma, suplementos alimenticios como Visaid Mácula, poseen en su composición, además de Lu y Ze, otros componentes antioxidantes, como vitaminas y sales minerales, estudiado en poblaciones de diversas características. Si bien se podría decir que hay similitud en cuanto a algunos de los componentes de estas formulaciones, no se ha demostrado la efectividad de todos.

Objetivos: Evaluar la eficacia de un lubricante oftálmico con aceite de semilla de girasol ozonizado, fosfolípidos de soja y 0,3% de hipromelosa en población usuarias de LC. Material y método: Estudio prospectivo, longitudinal y controlado de 46 sujetos. Los participantes se dividieron en grupo tratamiento y grupo control de manera aleatoria y equitativa. Al primer grupo se les administró la lágrima compuesta por aceite de semilla de girasol ozonizado, fosfolípidos de soja y 0,3% de hipromelosa. Y el grupo control, se trató con una lágrima compuesta por hipromelosa. Se analizó la altura del menisco lagrimal (AML) en población usuaria de lentes de contacto (LC) a través de una metodología no invasiva por interferometría óptica (Ocular Surface Analyser), así como la sintomatología con el test CLDEQ8. Resultados: El volumen del menisco lagrimal no fue significativamente mayor en ninguno de los dos grupos, sin embargo, el grupo tratamiento experimentó un mayor confort con sus lentes de contacto. Conclusión: El aceite de semilla de girasol ozonizado, fosfolípidos de soja y 0,3% de hipromelosa resultó ser un método poco efectivo para el tratamiento del ojo seco en lo que se refiere al volumen del menisco lagrimal., Objectives: To evaluate the effectiveness of an ophthalmic lubricant containing ozonized sunflower seed oil, soy phospholipids, and 0.3% hypromellose in users of contact lenses. Material and method: Prospective, longitudinal, controlled study with 46 subjects. The participants were randomly and equally divided into a treatment group and a control group. The treatment group received the eye drop composed of ozonized sunflower seed oil, soy phospholipids, and 0.3% hypromellose. The control group was treated with an eye drop composed of hypromellose. The height of the tear meniscus (HTM) in contact lens users was analyzed using non-invasive optical interferometry (Ocular Surface Analyzer), as well as symptomatology using the CLDEQ8 test. Results: The volume of the tear meniscus was not significantly greater in neither of the two groups; however, the treatment group experienced greater comfort with their contact lenses. Conclusion: Ozonized sunflower seed oil, soy phospholipids, and 0.3% hypromellose proved to be an ineffective method for the treatment of dry eye in terms of tear meniscus volume.

La superficie ocular se encuentra expuesta al entorno externo y por tanto existen muchas facilidades de que patógenos adversos y oportunistas colonicen y alteren la microbiota ocular produciendo o aumentando el riesgo de sufrir infecciones oculares. Las patologías oculares han sido frecuentemente tratadas administrando una terapia antibiótica, pero el uso excesivo de estos medicamentos está provocando la existencia de cepas bacterianas resistentes a estos. Con la intención de evitar estas resistencias a los antibióticos, actualmente se recurre al uso de soluciones antisépticas como método de profilaxis en el tratamiento de infecciones oculares. Estos antisépticos son biocidas que se encargan de inhibir el crecimiento de los microorganismos y presentan acción selectiva por lo que es menos probable que puedan originar resistencias a microorganismos. El objetivo de esta revisión sistemática fue valorar la acción antibacteriana, antifúngica, antiviral y antiinflamatoria, entre otras, de diferentes antisépticos utilizados en el ámbito oftalmológico, como son la povidona yodada, la clorhexidina, el ácido hipocloroso, el aceite ozonizado… y así potenciar su uso como tratamiento profiláctico de infecciones oculares. La búsqueda bibliográfica se realizó en diferentes bases de datos (Scopus, Pubmed, Wos y CINAHL) en los meses entre febrero y mayo de 2023. Se encontraron 1160 artículos diferentes, de los cuáles finalmente se incluyeron 14 artículos. Todos estos artículos son estudios o ensayos clínicos llevados a cabo entre 2019 y 2023. En todos ellos se valora la eficacia que presentan frente a microorganismos y comparan su acción a la de colirios que incluyen antibióticos en su composición. Esta revisión mostró que actualmente se ha incrementado el uso de colirios no antibióticos como profilaxis pre y post cirugía y coadyuvante de patología ocular bacteriana, fúngica y vírica., The ocular surface is exposed to the external environment, making it susceptible to colonization and alteration of the ocular microbiota by harmful and opportunistic pathogens, which can increase the risk of ocular infections. Ocular pathologies have often been treated with antibiotic therapy, but the excessive use of these drugs is leading to the emergence of bacterial strains that are resistant to them. To prevent antibiotic resistance, the current approach involves the use of antiseptic solutions as a prophylactic method in the treatment of ocular infections. These antiseptics are biocides that inhibit the growth of microorganisms and have selective action, making it less likely for microorganisms to develop resistance. The objective of this systematic review was to evaluate the antibacterial, antifungal, antiviral, and anti-inflammatory actions, among others, of different antiseptics used in the field of ophthalmology, such as povidone-iodine, chlorhexidine, hypochlorous acid, ozonized oil, etc. The aim was to enhance their use as prophylactic treatment for ocular infections. A literature search was conducted in various databases (Scopus, PubMed, Wos, and CINAHL) between February and May 2023. A total of 1160 different articles were found, of which 14 articles were finally included. All these articles are studies or clinical trials conducted between 2019 and 2023. They assess the efficacy of these antiseptics against microorganisms and compare their action to that of eye drops containing antibiotics. This review showed that the use of non-antibiotic eye drops has increased as prophylaxis before and after surgery, as well as an adjuvant in bacterial, fungal, and viral ocular pathologies.

To achieve a broader public acceptance for electric vehicles based on lithium-ion battery (LIB) technology, long driving ranges, low cost, and high safety are needed. A promising pathway to address these key parameters lies in the further improvement of Ni-rich cathode materials for LIB cells. Despite the higher achieved capacities and thus energy densities, there are major drawbacks in terms of capacity retention and thermal stability (of the charged cathode) which are crucial for customer acceptance and can be mitigated by protecting cathode particles. We studied the impact of surface modifications on cycle life and thermal stability of LiNi0.90Co0.05Mn0.05O2 layered oxide cathodes with WO3 by a simple sol–gel coating process. Several advanced analytical techniques such as low-energy ion scattering, differential scanning calorimetry, and high-temperature synchrotron X-ray powder diffraction of delithiated cathode materials, as well as charge/discharge cycling give significant insights into the impact of surface coverage of the coatings on mitigating degradation mechanisms. The results show that successful surface modifications of WO3 with a surface coverage of only 20% can prolong the cycle life of an LIB cell and play a crucial role in improving the thermal stability and, hence, the safety of LIBs.

We report a facile, solvent-free surfactant-dependent mechanochemical synthesis of highly luminescent CsPbBr3 nanocrystals (NCs) and study their scintillation properties. A small amount of surfactant oleylamine (OAM) plays an important role in the two-step ball milling method to control the size and emission properties of the NCs. The solid-state synthesized perovskite NCs exhibit a high photoluminescence quantum yield (PLQY) of up to 88% with excellent stability. CsPbBr3 NCs capped with different amounts of surfactant were dispersed in toluene and mixed with polymethyl methacrylate (PMMA) polymer and cast into scintillator discs. With increasing concentration of OAM during synthesis, the PL yield of CsPbBr3/PMMA nanocomposite was increased, which is attributed to reduced NC aggregation and PL quenching. We also varied the perovskite loading concentration in the nanocomposite and studied the resulting emission properties. The most intense PL emission was observed from the 2% perovskite-loaded disc, while the 10% loaded disc exhibited the highest radioluminescence (RL) emission from 50 kV X-rays. The strong RL yield may be attributed to the deep penetration of X-rays into the composite, combined with the large interaction cross-section of the X-rays with the high-Z atoms within the NCs. The nanocomposite disc shows an intense RL emission peak centered at 536 nm and a fast RL decay time of 29.4 ns. Further, we have demonstrated the X-ray imaging performance of a 10% CsPbBr3 NC-loaded nanocomposite disc.

Thin films of ice and water on soil particles play crucial roles in environmental and technological processes. Understanding the fundamental physical mechanisms underlying their formation is essential for advancing scientific knowledge and engineering practices. Herein, we focus on the role of the Casimir-Lifshitz force, also referred to as dispersion force, in the formation and behavior of thin films of ice and water on soil particles at 273.16 K, arising from quantum fluctuations of the electromagnetic field and depending on the dielectric properties of interacting materials. We employ the first-principles density functional theory (DFT) to compute the dielectric functions for two model materials, CaCO3 and Al2O3, essential constituents in various soils. These dielectric functions are used with the Kramers-Kronig relationship and different extrapolations to calculate the frequency-dependent quantities required for determining forces and free energies. Moreover, we assess the accuracy of the optical data based on the DFT to model dispersion forces effectively, such as those between soil particles. Our findings reveal that moisture can accumulate into almost micron-sized water layers on the surface of calcite (soil) particles, significantly impacting the average dielectric properties of soil particles. This research highlights the relevance of DFT-based data for understanding thin film formation in soil particles and offers valuable insights for environmental and engineering applications.