Search Results (3,323)

The city of Tlaxcala, located in central Mexico, is a small region with high industrial activity that releases potentially toxic elements (PTEs) into the environment. This study investigated the concentration, distribution, contamination levels, and human and ecological health risks of 14 PTEs in 100 urban dust samples collected between February and March 2025. The PTEs were analyzed using inductively coupled plasma optical emission spectrometry. The level of contamination was established using the contamination factor, enrichment, geoaccumulation index, and modified degree of contamination. We assessed human health risks based on non-carcinogenic and carcinogenic risks, as well as potential ecological risks associated with EPT exposure. The results revealed the presence of fourteen EPTs that exhibited the following pattern: Ti > Fe > Mn > Zn > Sb > Sr > Cr > V > Pb > Ni > Cu > Cd > As > Co, where Cd, Sb, and Ti showed high contamination (49.9, 292.6, 166.7) and extremely high enrichment (166.9, 1253, 471.9). The modified degree of contamination indicated contamination in more than 90% of the samples. The health risk index indicated a non-carcinogenic risk to children due to Sb exposure (HI = 2.9). The potential ecological risk was extremely high, with Sb, Cd, and Ti accounting for 99% of the total ecological risk. Although Tlaxcala is a small city, this study revealed high levels of Cd, Sb, and Ti contamination, as well as ecological and health risks to children due to Sb. This may be partly attributed to industrial activity and wastewater discharge from nearby cities such as Mexico City, Puebla, and the State of Mexico. Therefore, environmental and government authorities should consider these findings and reduce pollution levels accordingly. Full article

The Ni-doped Li₂B₄O₇ (Li₂O–2B₂O₃) glass was prepared by the conventional melt-quenching method. Structural and spectroscopic properties of the glass were investigated using X-ray diffraction (XRD), optical absorption, and photoluminescence spectroscopy, including excitation, emission, and decay kinetics. The absence of sharp diffraction peaks in the XRD pattern confirms the disordered glassy structure of the investigated glass. The optical absorption spectrum shows three broad bands associated with spin-allowed transitions of Ni²⁺ (3d⁸) ions. The excitation and emission spectra of the Li₂B₄O₇:Ni glass reveal several spin-allowed and spin-forbidden 3d–3d transitions of Ni²⁺ ions. In particular, the Li₂B₄O₇:Ni glass exhibits broad green and red emissions centred at approximately 525 and 687 nm, respectively, as well as weak near-infrared emission bands in the 900–1100 and 1500–1750 nm regions. The analysis of the crystal field splitting for Ni²⁺ ions in the Li₂B₄O₇:Ni glass is carried out, and the Racah parameters (B and C) and the crystal field strength (Dq) are calculated. The Tanabe–Sugano diagram for the octahedrally coordinated Ni²⁺ ions in the Li₂B₄O₇:Ni glass is built and discussed. Full article

Conventional approaches for badminton biomechanics assessment, such as optical motion capture, force plates, and wearable inertial sensors, are limited by occlusion, restricted coverage, or intrusiveness during high-intensity on-court movement. To address these limitations, this proof-of-concept study introduced microseismic monitoring for non-contact, full-court footwork analysis. A high-density edge-surrounding array of 20 Sercel DSU3 three-component MEMS digital geophones was deployed around a standard badminton court. Continuous vibration data were collected from three elite male badminton players during a 6-min high-intensity multi-ball defensive training protocol. Signal processing combined 10–150 Hz band-pass filtering, two-stage STA/LTA-AIC arrival picking, and a time-difference-of-arrival (TDOA) localization algorithm to detect and reconstruct footstep events. The proposed system achieved an overall localization mean absolute error of 31.4 ± 12.6 cm, with the spatial error distribution consistent with geometric dilution of precision. In addition, the distribution of footstep microseismic energy showed a strong GutenbergRichter-type scaling relationship (R² > 0.98, b ≈ 1.25). A Pareto-like pattern was also observed, with the most intense 20% of events accounting for approximately 61% of the total vibration-based load index. These findings support the feasibility of dense microseismic sensing as a non-invasive framework for full-court badminton footwork monitoring and exploratory athletic-load quantification. Given the pilot nature of this study, larger-scale validation with direct kinetic measurements and longitudinal designs is still required before practical application in fatigue assessment or injury-risk modeling. Full article

Purpose: To report baseline anterior scleral thickness (AST) values and evaluate regional and sex-related variation in healthy young Saudi adults using swept-source optical coherence tomography (SS-OCT). Methods: A prospective, cross-sectional study included 55 healthy Saudi adults aged 18–40 years. Participants underwent comprehensive ocular examinations to exclude pathology or significant refractive errors. AST was measured using IMAGEnet 6 software in superior, inferior, nasal, and temporal quadrants at 0 mm, 1 mm, and 2 mm from the scleral spur using the anterior segment module of swept-source OCT. Regional and sex-related differences were evaluated using a linear mixed-effects model adjusted for age and spherical equivalent. Short-term within-session intra-observer test–retest repeatability across repeated B-scan acquisitions was assessed using intraclass correlation coefficients, within-subject coefficients of variation, and Bland–Altman analysis. Results: The mean age of participants was 23.56 ± 4.61 years (34 males, 21 females). AST varied significantly according to distance and anatomical quadrant (both p < 0.001), with significant distance-by-quadrant (p < 0.001) and sex-by-distance-by-quadrant interactions (p = 0.010). The inferior quadrant generally showed greater thickness, while the superior quadrant showed lower values. Bonferroni-adjusted location-specific comparisons showed greater AST in males in the superior and temporal quadrants at both 1 mm and 2 mm from the scleral spur, whereas the remaining sex comparisons were not statistically significant. Neither age nor spherical equivalent showed a significant independent association with AST. Intra-observer ICC values ranged from 0.872 to 0.939. Conclusions: AST in young Saudi adults varies according to anatomical quadrant and distance from the scleral spur, with sex-related differences showing location-dependent patterns. These findings provide descriptive baseline data for anterior scleral morphology in this population. Full article

Background and Objectives: Ocular hypertension (OHT) is associated with a variable risk of progression to primary open-angle glaucoma, and early detection of functional abnormalities is important during follow-up. The 24-2C visual field pattern was designed to improve central sampling by adding 10 test locations to the conventional 24-2 grid. This study aimed to compare central visual field findings obtained with the 24-2 and 24-2C protocols in patients with OHT. Materials and Methods: This prospective, single-center, paired comparative study included 60 eyes of 60 patients with OHT. Each eye underwent 24-2 and 24-2C testing using the SITA Faster strategy during the same visit, with randomized test order. Global indices, test duration, the number of abnormal points within the central 10°, central mean sensitivity, and the presence of abnormal central clusters were compared between protocols. Peripapillary retinal nerve fiber layer (RNFL) and macular ganglion cell complex (mGCC) thicknesses were measured using spectral-domain optical coherence tomography, and structure–function relationships were explored. Results: Mean deviation, pattern standard deviation, visual field index, false-positive rate, and central mean sensitivity did not differ significantly between protocols. Test duration was longer with 24-2C than with 24-2 (167.4 ± 39.2 vs. 141.6 ± 31.9 s; p < 0.001). The number of abnormal points at p < 0.05 within the central 10° was higher with 24-2C (3.81 ± 3.6 vs. 2.35 ± 2.4; p = 0.006). Abnormal central clusters were detected in 19 eyes (31.7%) with 24-2C and 9 eyes (15.0%) with 24-2 (p = 0.031). Among eyes classified as normal on 24-2, 14 of 51 (27.5%) showed a central cluster on 24-2C. No significant correlations were found between central functional parameters and average RNFL or mGCC thicknesses. Conclusions: 24-2C detected more central abnormalities than 24-2 in eyes with OHT, while global visual field indices remained similar. Longitudinal studies are needed to establish the reproducibility and prognostic relevance of these additional findings. Full article

Coastal waters exhibit pronounced spatial and temporal variability in optical properties and water quality, which cannot be fully characterized by observations from discrete monitoring stations. Satellite Optical Water Type (OWT) classification provides spatially continuous information on optical conditions. However, comparisons with water quality observations have generally relied on the assigned OWT, and it remains unclear whether membership provides additional information within the same class. This study examined the relationships of assigned OWTs and membership with monthly water quality conditions in Guangdong coastal waters. Sentinel-3 OLCI observations acquired from 2017 to 2024 were matched with station observations of dissolved inorganic nitrogen (DIN), dissolved inorganic phosphorus (DIP), chemical oxygen demand (COD), dissolved oxygen (DO), and eutrophication classes. The analysis first compared water quality among assigned OWTs and then evaluated the secondary OWT and membership values within OWT 4a, the class with the largest sample size. Assigned OWTs distinguished broad differences in DIN, DIP, COD, and eutrophication classes, whereas DO did not differ significantly among OWTs. Within OWT 4a, the class associated with the second highest membership separated records with different nutrient, COD, and eutrophication conditions. Continuous membership values provided further information, but their relationships with water quality depended on the secondary OWT and were most consistent for DIN. OWT occurrence and station eutrophication patterns showed partial spatial correspondence, particularly around the Pearl River Estuary and Huangmao Bay. These findings show that assigned OWTs identify broad water quality differences, while secondary OWTs and membership values distinguish additional variation within OWT 4a. The mapped optical patterns provide complementary spatial context for interpreting station-based water quality observations. Full article

Additive manufacturing (AM) deposits material layer-by-layer, allowing for more geometric freedom than traditional manufacturing methods and reducing waste material. One barrier to industrially using AM components for structural applications is the ability to quantify defects and qualify components post-manufacture. This paper aims to demonstrate a feature identification and geometric quantification method from multiple ultrasonic waves captured in a raster pattern for AM components with multiple closely packed, similarly shaped features extruded on a component’s interior surface. This approach’s uniqueness is a means to quantify different feature dimensions, specifically the hexagonal longitudinal diagonal and extrusion height, within a dense field of features using a semi-automated image processing method. This approach is demonstrated on stainless steel components manufactured via the fused filament fabrication process utilizing a polymer carrier that is removed during post-processing. Results are validated by characterizing the as-manufactured geometric dimensions utilizing optical microscopy for features with nominal long diagonals of 4.06 mm and nominal extrusion heights ranging from 1 mm to 2 mm. The presented image processing technique has a planar measurement quantification error ranging from −0.1 mm to −0.7 mm and a feature extrusion height quantification error ranging from −0.30 mm to 1.24 mm across a range of sample thicknesses from 2 mm to 7 mm. Full article

The Stone Age marked the extensive use of rocks for tool-making, with flint as the primary material. However, prehistoric communities, ranging from the Early Lower Paleolithic to the Holocene, also utilized other stones like quartz due to their availability and suitability for manufacturing tools. Quartzose raw materials (quartz and quartzite) were widely exploited during prehistory, particularly in contexts where flint or other sources were scarce or unavailable. However, there are recorded findings of quartz tools from sites located in areas where flint sources were effectively accessible and exploited, such as at the Early Middle Paleolithic (EMP) site of Coudoulous I. This site presents a good opportunity to discuss the subsistence strategies and raw material procurement of Neanderthals in southwestern France and to explore methodological considerations related to the analysis of quartz assemblages. We examined 79 quartz and quartzite artifacts from layer 4 of a bone bed dating back to Marine Isotope Stage 6 (MIS 6), employing optical and digital microscopy along with a comprehensive reference collection. As a result, it was the most commonly identified activity. The hunting-oriented nature of the site is further supported by the limited evidence of other activities, apart from a few instances of scraping or cutting wood and dry hide, which are likely associated with the creation and maintenance of the tools used for hunting. Additionally, some quartz and quartzite artifacts with convergent edges display wear patterns consistent with their use as spear points. Therefore, the lithic industry at Coudoulous I highlights the significance of quartz and quartzite in EMP subsistence strategies and indicates that quartzose materials should not be undervalued or dismissed as opportunistic behavior. Full article

The high-precision laser micromachining of thermally sensitive PMMA polymers is severely limited by thermal accumulation, which deteriorates the surface quality of micro-hole arrays. Current laser drilling path optimization strategies predominantly prioritize geometric efficiency by minimizing travel distance, whereas quantitative thermal-constrained path optimization for PMMA micro-hole drilling remains underexplored. This work proposes a constrained simulated-annealing (SAA) path-planning strategy that embeds physical thermal constraints (critical thermal radius R and spacing threshold M) into the classic meta-heuristic algorithm, effectively suppressing transient thermal superposition between adjacent micro-holes while maintaining acceptable machining efficiency. Compared with the conventional sequential scanning mode (SSM), the SAA strategy reduces the molten deposit width around micro-holes by 22.3% under identical machining conditions (3 W laser power, 60 mm/s scanning speed, and a single scanning pass). A inherent trade-off is also observed: the thermally isolated jump path increases the total travel distance, resulting in approximately 1.3-fold longer machining time. Benefiting from the suppressed thermal accumulation, the SAA path effectively eliminates thermal-induced micro-hole coalescence at a compact hole spacing of 50 μm, yielding well-defined micro-hole contours and enabling the reliable fabrication of high-quality E-shaped structural color patterns with tunable optical responses under natural light. Full article

The long-term association between professional athletic training and ocular microvascular characteristics remains unclear. This cross-sectional study compared retinal and choroidal optical coherence tomography angiography (OCTA) parameters between 31 male professional handball players with at least five years of training and 30 age-matched sedentary male controls. The right eye of each participant was imaged using a 6 × 6 mm OCTA macular scan (NIDEK RS-3000 Advance). Foveal avascular zone (FAZ) metrics, vessel density (VD), perfusion density (PD), retinal nerve fiber layer (RNFL) thickness, and ganglion cell complex (GCC) thickness were evaluated, and p values were adjusted using the Benjamini–Hochberg false discovery rate procedure. FAZ metrics, RNFL thickness, and GCC thickness did not differ significantly between groups after correction for multiple comparisons. In contrast, all eight retinal and choroidal VD and PD parameters were lower in professional handball players, with adjusted p values ranging from <0.001 to 0.004 and moderate-to-large effect sizes (rank-biserial r = 0.449–0.668). Professional handball participation was associated with lower OCTA-derived retinal and choroidal vascular metrics despite comparable structural OCT parameters. Longitudinal studies are needed to confirm the physiological significance and causal basis of this pattern. Full article

Ultraviolet (UV)-C photodetectors based on perovskite semiconductors are attractive because of their solution processability and excellent optoelectronic properties, but UV-induced degradation limits conventional UV-based processing. Here, controlled ultraviolet light exposure is repurposed as a surface-engineering and patterning strategy. Shadow-mask-assisted irradiation selectively thinned the perovskite surface, while X-ray diffraction and UV–vis spectroscopy indicated that the main crystalline perovskite phase and overall optical absorption characteristics remained largely unchanged. Patterning conditions were systematically varied using patterning times of 3–10 min and circular pattern diameters of 0.3–1.0 mm. The optimized condition of a 7 min patterning time and a 0.5 mm pattern diameter reduced the dark current and enhanced the photocurrent, resulting in improved responsivity, external quantum efficiency, and specific detectivity. Cross-sectional microscopy and profilometry confirmed controllable surface thinning without macroscopic delamination, while XRD indicated preservation of the detectable crystalline perovskite phase under the investigated conditions. The observed performance enhancement is discussed in terms of possible changes in near-surface electrical losses and optical/carrier-transport pathways associated with controlled surface thinning. These results demonstrate that controlled ultraviolet light irradiation can function as a surface-modification strategy for improving perovskite UV photodetectors while maintaining the principal crystallographic and optical characteristics under the investigated conditions. Full article

Artificial intelligence (AI) is increasingly able to infer apparent fishing activity, vessel type, encounters, non-cooperative or otherwise low-visibility vessel presence, and other maritime patterns from Automatic Identification System (AIS), vessel monitoring system (VMS), radar, optical imagery and catch records. Yet better detection does not automatically produce better fisheries management. This article asks under what institutional conditions AI-enabled monitoring can support more effective compliance and the sustainability of shared fish stocks without converting probabilistic signals into automatic enforcement findings. Using the Korea–China Yellow Sea as an institutional case study, the analysis combines recent AI-fisheries literature, international monitoring–control–surveillance guidance, ecosystem-based fisheries scholarship, the Korea–China Fisheries Agreement and verifiable official enforcement and resource-management developments through August 2026. It develops an Adaptive Fisheries Intelligence Loop (AFIL) with five stages: observe, validate, respond, learn and adapt. The model requires human validation of algorithmic signals, provenance labels for shared information, feedback from enforcement outcomes, and a second feedback channel connecting compliance patterns to ecological indicators and management measures. Applied to the Yellow Sea, AFIL supports joint risk vocabularies, interoperable case and vessel histories, targeted patrols, scientific stock assessment and periodic recalibration of both algorithms and management rules. AFIL is an institutionally plausible and testable governance design, not an empirically validated prediction that AI will itself deliver compliance. The article therefore argues that AI should be governed as adaptive decision-support infrastructure rather than as an automated enforcement endpoint. Full article

Background: Intravascular lithotripsy (IVL) is an established calcium modification strategy for severely calcified coronary lesions. The Shunmei ShockFast™ IVL system is a novel device that appeared safe and feasible in an initial clinical experience. However, its calcium fracture typology, depth distribution, and quantitative stent optimization characteristics have not been characterized by serial optical coherence tomography (OCT). Objectives: To provide the first dedicated serial OCT sub-study of calcium modification patterns and stent optimization metrics achieved with the ShockFast™ IVL system in a cohort of patients with severely calcified de novo coronary lesions. Methods: This is a prospective, single-center OCT imaging sub-study nested within the Cardio-FR registry (NCT04185285). We included 14 patients with OCT assessment performed at three mandatory time points—baseline (before any device delivery), post-IVL, and post-stenting–who underwent PCI with the ShockFast™ IVL system between June 2025 and April 2026. The primary endpoint was OCT-confirmed calcium fracture rate following IVL treatment. Secondary endpoints included calcium fractures ≥2 and type, post-lesion-preparation lumen gain, minimum stent area (MSA), stent expansion (SE), malapposition, and edge dissection rates. Exploratory correlative analyses between baseline calcium morphology and post-IVL stent optimization outcomes were performed. Results: Median baseline OCT MLA was 2.22 mm² (IQR 1.4–3.61). Calcium fractures were identified in 10 of 14 lesions (71%, 95% CI 45–88%) following a lesion-preparation strategy incorporating ShockFast™ IVL, with ≥2 fractures in 43%. Fractures were classified as partial-thickness (non-transmural) in 30% and full-thickness (transmural) in 70% of cases. Median post-lesion-preparation lumen gain was 0.53 mm² (IQR 0.3–0.84). Median final MSA was 4.77 mm² (IQR 3.59–5.34) and median SE was 89.5% (IQR 85–94), with SE >80% achieved in 100% of lesions. No major malapposition or medial edge dissections were recorded. Conclusions: Applied as the central calcium-modification component of a comprehensive lesion-preparation strategy, the ShockFast™ IVL system was associated with OCT-confirmed calcium fractures in the majority of the lesions, with favorable stent expansion and optimization metrics in the absence of major malapposition or edge dissections. These findings provide the first dedicated serial OCT sub-study of calcium modification mediated by a lesion-preparation strategy incorporating ShockFast™ IVL, consistent with feasibility as a novel IVL platform suitable for further investigation in adequately powered comparative studies. Full article

The bonding performance of restorative composites to Biodentine™ XP remains insufficiently characterised, particularly regarding the influence of adhesive strategies on mechanical behaviour and fracture characteristics. This in vitro study evaluated the shear bond strength between Biodentine™ XP and a flowable bulk-fill composite using four restorative protocols: acid etching with Prime&Bond^® NT (G1), acid etching with Scotchbond™ Universal (G2), Scotchbond™ Universal without prior acid etching (G3), and no adhesive treatment (G4). Cylindrical specimens measuring 4.7 mm in diameter and 7 mm in total height were prepared, comprising 3 mm of Biodentine™ XP and 4 mm of composite. Uncured composite was placed directly onto the Biodentine™ XP surface and light-cured in situ following one of four bonding protocols. Specimens were stored for 72 h at 37 °C and 100% relative humidity before shear bond strength testing. Fracture patterns were assessed by optical microscopy, and representative surfaces were characterised using scanning electron microscopy and energy-dispersive X-ray spectroscopy. Significant differences in bond strength were detected among groups (p = 0.002), with G4 showing significantly lower values than G1 and G2. No significant differences were observed among the adhesive-treated groups. Fracture-pattern distribution also differed significantly (p < 0.001); acid-etched groups showed no adhesive failures, whereas adhesive failures occurred in G3 and were most frequent in G4. SEM-EDS revealed morphological and elemental differences among the selected fractured regions. Within the limitations of this short-term in vitro study, adhesive treatment improved bonding between Biodentine™ XP and the bulk-fill composite. Phosphoric acid etching did not significantly increase bond strength among adhesive-treated groups but was associated with a different failure-mode distribution. The mechanisms underlying these findings require direct chemical and long-term interfacial investigation. Full article

The demand for rapid, objective, and non-destructive methods to evaluate maize seed quality has grown as conventional tests often lack the sensitivity to detect subtle physiological or structural differences. To date, the use of multispectral markers (an emerging non-destructive technique) for diagnosing maize seed vigor remains poorly investigated. This study aimed to develop and validate machine learning models for classifying maize seed lots using multispectral imaging as a reliable optical marker for distinguishing seed vigor. Multispectral images from 19 wavelengths (365–970 nm) were collected for commercial seed lots of four maize hybrids and compared with physiological performance (normal seedlings and vigor), anthocyanin accumulation, and X-ray analyses. X-ray and multispectral imaging revealed clear patterns associated with reduced seed vigor. Random Forest analysis highlighted the 365 nm UV band as the most informative wavelength for discrimination, effectively separating high- and low-vigor lots. Quadratic discriminant analysis (QDA) and support vector machine (SVM) models were trained using the full multispectral range to enhance classification precision. QDA achieved the highest overall accuracy and showed more consistent performance across hybrids. Overall, the findings demonstrate that multispectral imaging, particularly through UV-based markers, provides a rapid, accurate, and non-invasive alternative for seed vigor assessment. This approach improves real-time decision-making in maize seed production systems. Full article