Search Results (334)

To enable accurate evaluation of satellite laser communication terminals under solar outage interference, this paper presents the design and implementation of a solar radiation simulation system targeting the 1540–1560 nm communication band. The system reconstructs co-propagating interference conditions through standardized and continuously tunable output, based on high irradiance and spectral uniformity. A compound beam homogenization structure—combining a multimode fiber and an apodizator—achieves 85.8% far-field uniformity over a 200 mm aperture. A power–spectrum co-optimization strategy is introduced for filter design, achieving a spectral matching degree of 78%. The system supports a tunable output from 2.5 to 130 mW with a 50× dynamic range and maintains power control accuracy within ±0.9%. To suppress internal background interference, a BRDF-based optical scattering model is established to trace primary and secondary stray light paths. Simulation results show that by maintaining the surface roughness of key mirrors below 2 nm and incorporating a U-shaped reflective light trap, stray light levels can be reduced to 5.13 × 10⁻¹² W, ensuring stable detection of a 10⁻¹⁰ W signal at a 10:1 signal-to-background ratio. Experimental validation confirms that the system can faithfully reproduce solar outage conditions within a ±3° field of view, achieving consistent performance in spectrum shaping, irradiance uniformity, and background suppression. The proposed platform provides a standardized and practical testbed for ground-based anti-interference assessment of optical communication terminals. Full article

The effective suppression of inflammation using disease-modifying therapies is essential in the treatment of multiple sclerosis (MS). Anti-CD20 monoclonal antibodies are commonly used long-term as maintenance therapies, largely due to the lack of reliable biomarkers to guide dosing and evaluate treatment response. However, prolonged use increases the risk of infections and other immune-mediated side effects. The unique ability of brain-derived blood extracellular vesicles (EVs) to cross the blood–brain barrier and reflect the central nervous system (CNS) immune status has sparked interest in their potential as biomarkers. This study aimed to assess whether blood-derived L1CAM⁺ EVs could serve as biomarkers of treatment response to rituximab (RTX) in patients with relapsing-remitting MS (RRMS). Serum samples (n = 25) from the baseline (month 0) and after 6 months were analyzed from the RTX arm of the ongoing randomized clinical trial OVERLORD-MS (comparing anti-CD20 therapies in RRMS patients) and were compared with serum samples from healthy controls (n = 15). Baseline cerebrospinal fluid (CSF) samples from the same study cohort were also included. EVs from both serum and CSF samples were characterized, considering morphology, size, and concentration, using transmission electron microscopy (TEM) and nanoparticle tracking analysis (NTA). The immunophenotyping of EV surface receptors was performed using flow cytometry with the MACSPlex exosome kit, while label-free quantitative proteomics of EV protein cargo was conducted using a proximity extension assay (PEA). TEM confirmed the presence of EVs with the expected round morphology with a diameter of 50–150 nm. NTA showed significantly higher concentrations of L1CAM⁺ EVs (p < 0.0001) in serum total EVs and EBNA1⁺ EVs (p < 0.01) in serum L1CAM⁺ EVs at baseline (untreated) compared to in healthy controls. After six months of RTX therapy, there was a significant reduction in L1CAM⁺ EV concentration (p < 0.0001) and the downregulation of TNFRSF13B (p = 0.0004; FC = −0.49) in serum total EVs. Additionally, non-significant changes were observed in CD79B and CCL2 levels in serum L1CAM⁺ EVs at baseline compared to in controls and after six months of RTX therapy. In conclusion, L1CAM⁺ EVs in serum showed distinct immunological profiles before and after rituximab treatment, underscoring their potential as dynamic biomarkers for individualized anti-CD20 therapy in MS. Full article

Prolonged ultraviolet (UV) exposure accelerates aging and degradation, while conventional constant-intensity UV simulations do not reflect the variable nature of outdoor radiation. Aging duration and film thickness are both key factors affecting Rubber-Modified Asphalt (RMA), but how their combination influences RMA remains unclear. To address this limitation, this research employed accelerated aging experiments under variable-intensity UV radiation to investigate the performance and aging mechanism of RMA across different aging durations and asphalt film thicknesses. Rheological properties were analyzed through rheological tests, and the UV aging mechanisms of RMA were revealed using FTIR and SEM. The results revealed that crumb rubber improved RMA’s UV aging resistance, including high-temperature performance, fatigue life, and low-temperature cracking resistance. Aging effects were more influenced in RMA with thinner films under prolonged UV exposure. After nine cycles of ultraviolet aging, the rutting resistance, elastic recovery, fatigue life, and low-temperature cracking resistance of RMA with a 1 mm film thickness were 1.33, 1.11, 0.54, and 0.67 times, respectively, those of RMA with a 2 mm film thickness subjected to three UV aging cycles. RMA demonstrated comparable high-temperature performance and elastic recovery under UV aging conditions corresponding to a 1.5 mm film thickness aged for three cycles and a 2.0 mm film thickness aged for six cycles, as well as a 1.0 mm film thickness aged for six cycles and a 1.5 mm film thickness aged for nine cycles. FTIR showed that the increased activity of C=C and C-H under photo-oxidative aging caused a greater impact on the carbonyl groups than the sulfoxide groups. Under high-intensity UV radiation, RMA with thinner films exhibited greater rubber powder detachment, increased surface oxidation, and a substantial widening of cracks. The rubber powder absorbed UV radiation, enhancing the stability of RMA. The maximum crack width of the 1 mm NA was twice that of RMA. These provided insight into the microstructural pattern of cracking resistance degradation caused by aging. This research provides theoretical support for the optimization of the anti-aging performance of RMA. Full article

This study aims to develop a stress-optimized ultra-broadband beam-splitting coating that integrates four spectral bands by analyzing the beam-splitting properties of coatings spanning visible to medium and long-wave infrared regions. A beam-splitting coating was deposited on a Ge substrate using ion-beam-assisted thermal evaporation, employing Ge, ZnS, and YbF₃ as coating materials. The designed coating exhibits high reflectance in the 0.5–0.8 μm and 0.9–1.7 μm wavelength bands while maintaining high transmittance in the 3–5 μm and 8–12 μm bands. The optimal deposition process for a single-layer coating was established, at a 45° incidence angle, the beam-splitting coating achieved an average reflectance (Rave) of 86.6% in the 0.9–1.7 μm band and 93.7% in the 0.9–1.7 μm band, alongside an average transmittance (Tave) of 91.36% in the 3–5 μm band and 91.3% in the 8–12 μm band. The antireflection coating achieved a single-side Tave of 98.5% in the 3–5 μm band and 97% in the 8–12 μm band. The coating uniformity exceeded 99.6%. To optimize the surface profile, a single-layer Ge coating was added to the rear surface, resulting in a root mean square deviation of less than 0.0007 μm, achieved the same precision of the surface profile successfully. The deposited beam-splitting coating possessed high surface profile precision, and successfully achieved high reflectance in the visible to short-wave infrared range and high transmittance in the medium- and long-wave infrared range. The coating demonstrated excellent adhesion, abrasion resistance, and structural integrity, with no wrinkling, cracking, or delamination. Full article

The low fluorescence quantum efficiency of hydrophilic modified spiropyran in hydrogel matrices cannot be naturally improved during photoresponsive operation, which significantly limits their practical applications.In this study, a hybrid hydrogel system integrating metal plasmon resonance-enhanced fluorescence effects is designed through copolymerization of N,N′-bis(acryloyl)cystamine-modified Au nanoparticles (Au NPs), hydrophilic graft-modified spiropyran molecules, and N-isopropylacrylamide. This approach successfully achieves a spiropyran-based fluorescent hydrogel sensor with enhanced fluorescence intensity. Furthermore, an inverted pyramid-structured surface is engineered on the hydrogel using a template-assisted strategy, combining anti-reflection optical effects with plasmonic enhancement mechanisms. Molecular modification facilitated the integration of spiropyran and Au NPs into the hydrogel molecular chains, enhancing the dispersion of Au NPs within the hydrogel matrix and preventing fluorescence quenching from direct contact between Au NPs and spiropyran. Additionally, the anti-reflection effect of the hydrogel surface microstructure and the plasmon resonance effect of Au NPs were crucial in boosting the sensor’s fluorescence. Finally, the fluorescence intensity of the hydrogel increased by 10.2 times. In addition, under the action of excitation light, this sensor exhibited dual responsiveness of colorimetry and fluorescence, allowing for the sensing of heavy metal ions. The limit of detection for Zn²⁺ is as low as 0.803 μM, and the hydrogel exhibited more than 10 cycles of photo-isomerization and ion responsiveness. Full article

Aging and aging-related neurodegenerative disorders, such as Alzheimer’s disease, are characterized by chronic inflammation that progressively damages nervous tissue within the central nervous system (CNS). In addition to cytokines, lectin-like carbohydrate recognition molecules play a critical role in modifying cellular communication during inflammation. Among these, galectins—particularly anti-inflammatory galectin-1 and pro-inflammatory galectin-3—stand out due to their immunological functions and specificity for N-acetyllactosamine structures. Almost every cell type within the CNS can express and recognize galectins, influencing various essential cellular functions. N-acetyllactosamines, the ligand structures recognized by galectins, are found beneath sialylated termini in protein-linked oligosaccharides. During aging, protein-linked oligosaccharide structures become shorter, exposing N-acetyllactosamines on protein surfaces, which enhances their availability as binding sites for galectins. Genomic studies indicate that the number of galectin-1- and galectin-3-expressing microglial cells increases with age- or age-related disease (Alzheimer’s disease), reflecting an aging-associated rise in galectin concentrations within the CNS. This increase parallels a rise in free N-acetyllactosamine-like ligands, suggesting that galectin-N-acetyllactosamine interactions gain prominence and play a more significant role in aging-related CNS disorders. Understanding these interactions and their molecular implications offers potential avenues for targeted therapeutic strategies in combating aging-related CNS inflammation and neurodegeneration. Full article

Incorporating lead (Pb) into the germanium (Ge) lattice emerges as a promising approach for bandgap engineering, enabling luminescence at longer wavelengths and paving the way for enhanced applications in short-wave infrared (SWIR) light sources and photodetectors. In this work, we report on optical properties of GePb alloys fabricated by a complementary metal-oxide semiconductor (CMOS)-compatible process that includes Pb ion implantation followed by solid-phase epitaxial regrowth via flash-lamp annealing. Optical characterization, including photoluminescence spectroscopy and Fourier-transform infrared reflectance spectroscopy, reveals that GePb alloys exhibit a reduced bandgap compared to pure Ge, resulting in longer-wavelength emission, while also providing broadband antireflective properties below 1800 nm wavelengths due to the surface subwavelength nanostructure. These findings position nanostructured GePb as a highly promising candidate for SWIR optoelectronic applications. Full article

This study focuses on the nameplate of Vila D. Bosco, a modern building in Macau from the time of Portuguese rule, and looks at the types of metal materials and surface coatings used, as well as how they corrode due to the tropical marine climate affecting the building’s metal parts. The study uses different techniques, such as X-ray fluorescence spectroscopy (XRF), scanning electron microscopy/energy dispersive spectroscopy (SEM-EDS), X-ray diffraction (XRD), attenuated total internal reflectance Fourier transform infrared spectroscopy (ATR-FTIR), and cross-sectional microscopic analysis, to carefully look at the metal, corrosion products, and coating of the nameplate. The results show that (1) the nameplate matrix is a resulfurized steel with a high sulfur content (Fe up to 97.3% and S up to 1.98%), and the sulfur element is evenly distributed inside, which is one of the internal factors that induce corrosion. (2) Rust is composed of polycrystalline iron oxides such as goethite (α-FeOOH), hematite (α-Fe₂O₃), and magnetite (Fe₃O₄) and has typical characteristics of atmospheric oxidation. (3) The white and yellow-green coatings on the nameplate are oil-modified alkyd resin paints, and the color pigments are TiO₂, PbCrO₄, etc. The surface layer of the letters is protected by a polyvinyl alcohol layer. The paint application process leads to differences in the thickness of the paint in different regions, which directly affects the anti-rust performance. The study reveals the deterioration mechanism of resulfurized steel components in a subtropical polluted environment and puts forward repair suggestions that consider both material compatibility and reversibility, providing a reference for the protection practice of modern and contemporary architectural metal heritage in Macau and even in similar geographical environments. Full article

In this study, ZnS/YbF₃-10.6 µm antireflection (AR) coatings were fabricated on CVD single-crystal diamond and ZnSe substrates. The spectral characteristics of the coatings and their performance under continuous wave laser radiation at 10.6 µm were systematically investigated. The fabricated AR coatings exhibited excellent spectral properties in the target wavelength range. Both theoretical calculations and experimental results indicated that, at the same power density, the 10.6 µm AR coatings on diamond substrates exhibited a lower temperature rise compared to those deposited on ZnSe substrates. Due to its high thermal conductivity, the diamond substrate is expected to exhibit reduced thermally induced surface distortion. The laser-induced damage threshold (LIDT) test results indicate that the AR coating deposited on the ZnSe substrate exhibits a damage threshold of 11,890 W/cm², whereas the AR coating on the diamond substrate achieves a threshold of 15,287 W/cm², representing a 28.5% improvement over the ZnSe substrate. Additionally, graphite formation occurs on the diamond substrate under high power density. These findings provide both theoretical and experimental support for the potential application of diamond materials in high-power laser systems. Full article

The use of adalimumab biosimilars has become increasingly common in clinical practice, reflecting their growing acceptance and efficacy as therapeutic alternatives to reference biologics. However, studies investigating the molecular interactions between anti-adalimumab antibodies (AAA) elicited in patients and different adalimumab biosimilars remain limited. This study aims to characterize the kinetic interactions between purified AAA from pediatric patients with Juvenile Idiopathic Arthritis and three adalimumab formulations: the originator Humira^®, and the biosimilars GP2017 (Hyrimoz^®) and SB5 (Imraldi^®). For this purpose, adalimumab formulations were immobilized on a gold chip, and purified AAA were flowed to perform further kinetic analysis using the surface plasmon resonance (SPR) technology. Results showed that the K_D values for purified AAA from patients treated with biosimilars GP2017 (Hyrimoz^®) or SB5 (Imraldi^®) were comparable across all formulations tested, including the originator Humira^®. AAA interacted with Humira^®, Hyrimoz^®, and Imraldi^® with similar apparent affinity (10⁻⁹ M > K_D > 10⁻¹⁰ M); slight variations have been observed among patients, less among biosimilars. The similarity in K_D values across biosimilars and the originator supports the notion that, at the level of immunogenicity, biosimilars can be considered clinically comparable to the originator. Full article

The anti-reflective properties of silicon surfaces play a pivotal role in determining the light absorption efficiency of various silicon-based optoelectronic devices, with surface micro-nanostructures emerging as a crucial technological approach for achieving enhanced anti-reflection. In this study, inverted pyramid structures were employed as the micron-scale framework, and micro-nano composite structures were successfully prepared using an inductively coupled plasma (ICP) etching system. This paper, mainly focused on the micro-nano fabrication, investigated the effects of gas flow rate ratio (SF₆:O₂:C₄F₈), ICP power, RF power, and etching time on the surface morphology and reflectance of the composite structures. The results demonstrate that the optimal anti-reflective micro-nano composite structure was achieved under the following conditions: SF₆ flow rate of 18 sccm, O₂ flow rate of 9 sccm, C₄F₈ flow rate of 4 sccm, ICP power of 300 W, RF power of 5 W, and etching time of 5 min. The average reflectivity of the prepared surface structure was as low as 1.86%. Full article

The reflectance (R) of linear and circular micro-gratings on c-plane sapphire Al₂O₃ ablated by a femtosecond (fs) laser were spectrally characterised for thermal emission $\propto (1-R)$ in the mid-to-far infrared (IR) spectral range. An IR camera was used to determine the blackbody radiation temperature from laser-patterned regions, which showed (3–6)% larger emissivity dependent on the grating pattern. The azimuthal emission curve closely followed the Lambertian angular profile $\propto cos{\theta }_a$ at the 7.5–13 μm emission band. The back-side ablation method on transparent substrates was employed to prevent debris formation during energy deposition as it applies a forward pressure of >0.3 GPa to the debris and molten skin layer. The back-side ablation maximises energy deposition at the exit interface where the transition occurs from the high-to-low refractive index. Phononic absorption in the Reststrahlen region 20–30 μm can be tailored with the fs laser inscription of sensor structures/gratings. Full article

Helicobacter pylori is a pathogenic bacterium that causes gastric and extragastric diseases. We have previously demonstrated that one of the mechanisms of H. pylori-associated chronic immune thrombocytopenia involves immune complexes of platelets, a H. pylori protein Lpp20 and an anti-Lpp20 antibody. However, it remains unclear how Lpp20 enters the body. We hypothesize that bacterial extracellular vesicles (bEVs) transport Lpp20. Thus, this study assessed Lpp20 in the bEVs released from seven clinical H. pylori isolates, using immunoprecipitation (IP), immunoblotting (IB), and surface plasmon resonance imaging (SPRi), with anti-GroEL (a marker of bEVs) and anti-Lpp20 antibodies. Lpp20 and bEVs were each detected in lysates of all seven strains. IP–IB experiments demonstrated that bEVs containing Lpp20 were produced by five of the strains (J99, SS1, HPK5, JSHR3, and JSHR31). SPRi using an anti-Lpp20 antibody demonstrated significantly higher reflectance from the strain HPK5 than from its lpp20-disrupted strains (p < 0.01), indicating localization of Lpp20 on the bEVs’ surface; Lpp20 may also be contained within bEVs. The bEVs containing Lpp20 were not detected from two clinical H. pylori strains (26695 and JSHR6) or from two lpp20-disrupted strains (26695ΔLpp20 and HPK5ΔLpp20). Differences in Lpp20 detection in bEVs are likely due to variations in bEV production resulting from strain diversity. Full article

Hybrid polymers combine the benefits of inorganic and organic material properties, offering superior thermal, mechanical, and chemical stability, making them ideal for optical applications. This study focuses on the fabrication and characterization of antireflective (AR) structures within hybrid polymers using reactive ion etching (RIE). The etching process produces nanopillars with controlled heights, achieving excellent AR performance across a broad spectral range from 450 nm to 2 µm. Optical characterization, including angle-resolved transmission and reflection measurements, shows that the structured samples maintain high transmission efficiency and reduced reflectance at varying incidence angles. Thermal stability tests reveal that the AR structures preserve their optical properties after exposure to temperatures up to 250 °C. Higher temperatures cause significant material yellowing, which is attributed to changes in the bulk material rather than damage to the structured surface. Hydrophobicity measurements show significant water repellency in structured samples, with contact angles more than twice those of unstructured layers. These findings highlight the potential of hybrid polymers with moth-eye-inspired nanostructures for high-performance, durable optical components in demanding environments. Full article

Modern multi-junction solar cell technology offers a pathway to achieving consistent and high photovoltaic conversion efficiencies through enhanced solar spectrum absorption. Indeed, during the last years, the industries of solar cells have focused on optimizing device structures, utilizing both robust and delicate materials to maximize their performances. This paper presents the modeling and optimization of the electrical and structural properties of high-efficiency InGaP/GaAs double-junction solar cells, specifically without employing an anti-reflective coating. This developed structure has been achieved by introducing a buffer layer in the lower layer and incorporating an upper back surface field layer into the investigated cell structure. Furthermore, the optimization conducted in this paper using Silvaco-Atlas software (version 2018) under the AM1.5G spectrum reveals that the proposed InGaP/GaAs tandem cell configuration exhibits significant performance, reaching conversion efficiency of 41.585%. It can be said that this adapted structure yields a short-circuit current density of 21.65 mA/cm², an open-circuit voltage of 2.319 V, and a filling factor of 84.001%. Whereas this newly optimized structure demonstrates its effectiveness in enhancing solar cell efficiency performance, presenting highly promising results with potential significance for the devices’ optical and electrical properties. Full article