Search Results (327)

An ongoing challenge in pelagic oceanography and limnology is to quantify and understand the distribution of suspended particles and particle aggregates with sufficient temporal and spatial fidelity to understand their dynamics. These particles include biotic (mesoplankton, organic fragments, fecal pellets, etc.) and abiotic (dusts, precipitates, sediments and flocks, anthropogenic materials, etc.) matter and their aggregates (i.e., marine snow), which form a large part of the total particulate matter > 200 μm in size in the ocean. The transport of organic material from surface waters to the deep-sea floor is of particular interest, as it is recognized as a key factor controlling the global carbon cycle and hence, a critical process influencing the sequestration of carbon dioxide from the atmosphere. Here we describe the development of an oceanographic instrument, the Pelagic Laser Tomographer (PLT), that uses high-resolution optical technology, coupled with post-processing analysis, to scan the 3D content of the water column to detect and quantify 3D distributions of small particles. Existing optical instruments typically trade sampling volume for spatial resolution or require large, complex platforms. The PLT addresses this gap by combining high-resolution laser-sheet imaging with large effective sampling volumes in a compact, deployable system. The PLT can generate spatial distributions of small particles (~100 µm and larger) across large water volumes (order 100–1000 m³) during a typical deployment, and allow measurements of particle patchiness over spatial scales to less than 1 mm. The instrument’s small size (6 kg), high resolution (~100 µm in each 3000 cm² tomographic image slice), and analysis software provide a tool for pelagic studies that have typically been limited by high cost, data storage, resolution, and mechanical constraints, all usually necessitating bulky instrumentation and infrequent deployment, typically requiring a large research vessel. Full article

Glass wool waste constitutes a rapidly increasing fraction of construction and demolition residues, yet it remains one of the most challenging insulation materials to recycle. Its non-combustible nature, extremely low bulk density, and high fibre elasticity preclude energy recovery and severely limit conventional mechanical recycling routes, resulting in long-term landfilling and loss of mineral resources. Converting glass wool waste into a fine mineral powder represents a potentially viable pathway for its integration into low-carbon construction materials, provided that industrial scalability, particle-size control, and chemical compatibility with cementitious binders are ensured. This study investigates the industrial-scale milling of end-of-life glass wool waste in a ventilated horizontal ball mill. It compares two grinding routes: a corundum-free route (BK) and an abrasive-assisted route (ZK) employing α-Al₂O₃ corundum to intensify fibre fragmentation. Particle size distribution was quantified by laser diffraction using cumulative and differential analyses, as well as characteristic diameters. The results confirm that abrasive-assisted milling significantly enhances fragmentation efficiency and reduces the coarse fibre fraction. However, the study demonstrates that this gain in fineness is inherently coupled with the incorporation of α-Al₂O₃ into the milled powder, introducing a chemically foreign crystalline phase that cannot be removed by post-processing. From a cement-oriented perspective, this contamination represents a critical limitation, as α-Al₂O₃ may interfere with hydration reactions, aluminate–sulfate equilibria, and microstructural development in Portland and calcium sulfoaluminate binders. In contrast, the corundum-free milling route yields a slightly coarser, chemically unmodified powder, offering improved process robustness, lower operational complexity, and greater compatibility with circular economy objectives. The study establishes that, for the circular reuse of fibrous insulation waste in cementitious systems, particle fineness alone is insufficient as an optimization criterion. Instead, the combined consideration of fineness, chemical purity, and binder compatibility governs the realistic and sustainable reuse potential of recycled glass wool powders. Full article

Ultrasonic-assisted laser-directed energy deposition (UA-DED) is a promising combined technology for manufacturing high-value thin-walled Inconel 718 components in aerospace. Nevertheless, the optimal ultrasonic frequency—a key parameter for achieving desirable performance in thin-walled Inconel 718 alloys—remains to be determined. In this study, we systematically investigated the influence of ultrasonic frequency (12–20 kHz) on the microstructure and mechanical properties of thin-walled Inconel 718 fabricated by UA-DED. The results revealed that an ultrasonic frequency of 20 kHz was optimal and can yield significant improvements in the microstructures of the as-deposited sample coordinate planes, manifested by the complete suppression of large pores, three-dimensional refinement of the γ matrix grains, alleviation of Nb and Mo segregation, the reduction of fragmented Laves particles, a decrease in residual macroscopic stresses, and homogeneous distributions of γ′/γ″ phases and γ-grain orientation. Meanwhile, the application of a 20 kHz ultrasonic frequency endows the manufactured thin-walled 718 parts with superior mechanical properties, including a tensile strength of 899 MPa in the laser scanning direction and 877 MPa in the build direction, along with the corresponding elongations of 34.8% and 38.9%. This work demonstrates the potential of modulating ultrasonic frequency to tailor microstructures and produce high-performance thin-walled Inconel 718 aerospace components. Full article

Connected and Autonomous Electric Vehicles (CAEVs) and Uncrewed Aerial Vehicles (UAVs) are critical components of future Intelligent Transportation Systems (ITS), yet their deployment remains constrained by fragmented charging infrastructures and the lack of coordinated reservation and trip planning across static, dynamic wireless, and vehicle-to-vehicle (V2V) charging networks using magnetic resonance and laser-based power transfer. Existing solutions often struggle with misalignment sensitivity, unpredictable arrivals, and disconnected ground–aerial scheduling. This work introduces a three-layer architecture that integrates a handshake protocol for coordinated charging and billing, a misalignment correction algorithm for magnetic resonance and laser-based systems, and three scheduling strategies: Static Heuristic Charging Scheduling and Planning (SH-CSP), Dynamic Heuristic Charging Scheduling and Planning (DH-CSP), and the Safety, Scheduling, and Sustainability-Aware Feasibility-Enhanced Deep Deterministic Policy Gradient (SAFE-DDPG). SAFE-DDPG extends vanilla DDPG with feasibility-aware action filtering, prioritized replay, and adaptive exploration to enable real-time scheduling in heterogeneous and congested charging networks. Results show that SAFE-DDPG significantly improves scheduling efficiency, reducing average wait times by over 70% compared to DH-CSP and over 85% compared to SH-CSP, demonstrating its potential to support scalable and coordinated ground–aerial charging ecosystems. Full article

Background: Obstructive sleep apnea is characterized by recurrent upper airway obstruction during sleep, leading to intermittent hypoxemia, sleep fragmentation, and excessive daytime sleepiness. Affecting up to 11% of the adult Polish population and more commonly diagnosed in men, OSA poses a major public health concern due to its association with cardiovascular, metabolic, and neurocognitive complications. This review summarizes the current evidence on diagnostic methods, risk factors, and therapeutic approaches, with particular emphasis on oral appliance therapy using mandibular advancement devices (MADs). Methods: A systematic literature review was conducted using the PubMed and Scopus databases, covering publications from 2020 to 2025, including clinical trials, meta-analyses, and systematic reviews evaluating the efficacy and safety of MAD therapy. Results: Findings demonstrate that MAD effectively reduces apnea–hypopnea index (AHI) values, improves oxygen saturation, and alleviates snoring and daytime fatigue, offering a patient-tolerable alternative for those intolerant to continuous positive airway pressure (CPAP). However, long-term use may cause occlusal or dental changes. Novel techniques, such as Er:YAG laser therapy, show potential in treating mild OSA. Moreover, epidemiological data suggest a correlation between tooth loss and an increased risk of OSA, particularly among men over 65. Conclusions: Dentists play a pivotal role in early detection, screening, and interdisciplinary management of OSA, underscoring the importance of collaboration between dental professionals and sleep medicine specialists for comprehensive care. Full article

CO₂ laser processing has emerged as an efficient dry-finishing technique capable of inducing controlled chemical and morphological transformations in cotton and denim textiles. The strong mid-infrared absorption of cellulose enables localised photothermal heating, leading to selective dye decomposition, surface oxidation, and micro-scale ablation while largely preserving the bulk fabric structure. These laser-driven mechanisms modify colour, surface chemistry, and topography in a predictable, parameter-dependent manner. Low-fluence conditions predominantly produce uniform fading through fragmentation and oxidation of indigo dye; in comparison, moderate thermal loads promote the formation of carbonyl and carboxyl groups that increase surface energy and enhance wettability. Higher fluence regimes generate micro-textured regions with increased roughness and anchoring capacity, enabling improved adhesion of dyes, coatings, and nanoparticles. Compared with conventional wet processes, CO₂ laser treatment eliminates chemical effluents, strongly reduces water consumption and supports digitally controlled, Industry 4.0-compatible manufacturing workflows. Despite its advantages, challenges remain in standardising processing parameters, quantifying oxidation depth, modelling thermal behaviour, and assessing the long-term stability of functionalised surfaces under real usage conditions. In this review, we consolidate current knowledge on the mechanistic pathways, processing windows, and functional potential of CO₂ laser-modified cotton substrates. By integrating findings from recent studies and identifying critical research gaps, the review supports the development of predictable, scalable, and sustainable laser-based cotton textile processing technologies. Full article

Objectives: The Eight-chop technique is a mechanically based nuclear segmentation method designed to improve surgical efficiency and reduce intraocular tissue stress during phacoemulsification. Early postoperative aqueous flare serves as an objective indicator of surgical invasiveness, whereas corneal endothelial cell density (CECD) loss represents a structural measure of endothelial injury. Although both parameters are clinically important, their relationship has not been systematically investigated in the context of this newer mechanical fragmentation approach. Methods: This prospective observational study included 118 eyes from 70 non-diabetic patients undergoing uncomplicated Eight-chop phacoemulsification. Aqueous flare was measured preoperatively and at postoperative Day 1, Day 7, Week 7, and Week 19 using laser flare photometry. CECD was evaluated preoperatively and at Weeks 7 and 19. Changes over time were analyzed using paired t-tests. Linear mixed-effects models (random intercept = patient ID) were constructed to assess predictors of CECD loss and postoperative intraocular pressure (IOP) reduction. Explanatory variables included Day 1 flare, age, preoperative CECD, nucleus hardness (Emery-Little grade), cumulative dissipated energy (CDE), and irrigation fluid volume. Results: Postoperative flare increased significantly at all time points (all p < 0.001), peaking on Day 7 (16.7 ± 9.21 photon counts/ms). CECD loss was extremely small, averaging 1.38% at Week 7 and 1.46% at Week 19. In mixed-effects models, Day 1 flare was not associated with CECD loss at Week 7 (p = 0.35) or Week 19 (p = 0.85). Significant predictors of CECD loss included Emery-Little grade (p = 0.004 at Week 7; p = 0.025 at Week 19), with borderline contributions from CDE and irrigation volume. IOP decreased significantly at Weeks 7 and 19; however, Day 1 flare did not predict IOP reduction. Conclusions: Eight-chop phacoemulsification produced uniformly low postoperative inflammation and exceptionally small corneal endothelial cell loss. Early postoperative flare did not predict CECD loss, suggesting that the Eight-chop technique provides a highly standardized, low-invasiveness surgical environment. These findings suggest that the Eight-chop technique lowers ultrasound energy requirements and may help reduce corneal endothelial stress relative to standard phacoemulsification. Full article

This work demonstrates a three-step method for the synthesis and production of submicron spherical gold particles using laser ablation in liquid (LAL), laser-induced fragmentation in liquid (LFL), laser-induced nanochain formation, and laser melting in liquid (LML). The nanoparticles were characterized using transmission electron microscopy (TEM), dynamic light scattering (DLS), and UV–visible spectroscopy. In the first stage, spherical gold nanoparticles with a size of 20 nm were obtained using LAL and LFL. Subsequent irradiation of gold nanoparticle colloids with radiation at a wavelength of 532 nm leads to the formation of gold nanochains. Irradiation of nanochain colloids with radiation at a wavelength of 1064 nm leads to the formation of large spherical gold particles with a size of 50 to 200 nm. The formation of submicron gold particles upon irradiation of 2 mL of colloid occurs within the first minutes of irradiation and is complete after 480,000 laser pulses. Increasing the laser pulse energy leads to the formation of larger particles; after exceeding the threshold energy (321 mJ/cm²), fragmentation is observed. Increasing the concentration of nanoparticles in the initial colloid up to 150 μg/mL leads to a linear increase in the size of submicron nanoparticles. The use of picosecond pulses for irradiating nanochains demonstrates the formation of the largest particles (200 nm) compared to nanosecond pulses, which may be due to the effect of local surface melting. The described technique opens the possibility of synthesizing stable gold nanoparticles over a wide range of sizes, from a few to hundreds of nanometers, without the use of chemical reagents. Full article

Background: Active-fluidics phacoemulsification can maintain anterior chamber stability at lower intraoperative intraocular pressure (IOP) levels. However, whether reducing IOP alone—without additional stabilizing technologies such as the Active Sentry handpiece—can decrease surgical invasiveness during Eight-Chop phacoemulsification remains unclear. Methods: In this prospective fellow-eye comparative study, 56 non-diabetic patients (112 eyes) underwent Eight-Chop technique phacoemulsification using the Centurion Vision System with active fluidics. One eye was randomly assigned to a standard-IOP setting (55 mmHg; high-IOP group) and the fellow eye to a reduced-IOP setting (28 mmHg; low-IOP group). Intraoperative parameters—including operative time, phaco time, aspiration time, cumulative dissipated energy (CDE), and irrigation volume—were recorded. Postoperative outcomes included aqueous flare (laser flare photometry), corneal endothelial cell density (CECD) and CECD loss, corneal morphology (central corneal thickness [CCT], coefficient of variation [CV], percentage of hexagonal cells [PHC]), and IOP. Linear mixed-effects models with patient ID as a random effect were used for all paired-eye comparisons. Results: Lowering the intraoperative IOP did not reduce surgical invasiveness. Phaco time was significantly longer in the low-IOP group (16.2 ± 5.22 s vs. 13.9 ± 4.40 s; p = 0.001), and aspiration time was also longer (75.0 ± 18.3 s vs. 69.0 ± 17.9 s; p = 0.033). No significant differences were found in operative time (5.08 ± 1.10 min vs. 4.82 ± 1.13 min; p = 0.082), CDE (5.93 ± 1.87 vs. 5.56 ± 1.90; p = 0.099), or irrigation volume (26.6 ± 7.71 mL vs. 25.2 ± 7.35 mL; p = 0.214). Postoperative outcomes were similarly comparable. Aqueous flare showed no significant differences at any time point (e.g., day 1: 14.8 ± 5.10 vs. 14.5 ± 4.76 ph/ms; p = 0.655). Mean CECD loss remained small in both groups and did not differ significantly (7 weeks: −0.82 ± 1.05% vs. −0.98 ± 1.16%, p = 0.460; 19 weeks: −0.93 ± 1.38% vs. −1.28 ± 1.69%, p = 0.239). Corneal morphological parameters (CCT, CV, PHC) and postoperative IOP also showed no significant differences between settings. Conclusions: In this fellow-eye comparative study, lowering intraoperative intraocular pressure from conventional to near-physiologic levels under active-fluidics control did not reduce surgical invasiveness during Eight-chop phacoemulsification. No additional benefits were observed in terms of endothelial cell preservation, postoperative inflammation, or overall surgical performance. These findings indicate that, when chamber stability is already ensured by a low-invasive fragmentation strategy, further reduction in intraoperative IOP alone does not confer measurable short-term clinical advantages. Full article

The study conducted a review of Listeria prevalence, virulence, and adaptations associated with leafy vegetables from small-scale farms and their journey to markets. PubMed, Taylor and Francis, Oxford, and Google Scholar databases were utilised to search for English-language journal articles published between January 1992 and 2025. Studies utilised multi-locus sequence typing (MLST), polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP), multiplex PCR, pulsed-field gel electrophoresis (PFGE), and whole genome sequencing WGS, confocal scanning laser microscopy technique for the detection of Listeria species, followed by transcriptomic, phenotypic analyses, strand-specific RNA-sequencing, and membrane lipid profiling. ST₅, ST₁₂₁, and ST₃₂₁ are considered predominant and virulent and have been identified in two ready-to-eat commodities, while ST₁, ST₂, and ST₂₀₄ are considered hypervirulent strains in food processing environments. Immunocompromised groups can experience severe life-threatening infections, even death. Significant economic losses due to shutdowns for sanitary procedures can occur, impacting food security. Full article

Heterobimetallic iron–group 9 carbonyl cations, FeM(CO)_n⁺ (M = Rh, Ir; n = 9–11), were generated in the gas phase via pulsed laser vaporization within a supersonic expansion and characterized by infrared photodissociation spectroscopy in the carbonyl stretching region. By combining experimental spectra with density functional theory simulations, the geometric and electronic structures of these clusters were unambiguously assigned. Mass spectrometry and photodissociation results identified FeM(CO)₉⁺ as the saturated species for M = Rh and Ir, in contrast to the lighter cobalt analog FeCo(CO)₈⁺. The FeM(CO)₉⁺ cations adopt a C_4v-symmetric singlet ground-state structure with all carbonyl ligands terminally bound, corresponding to a (OC)₅Fe–M(CO)₄ configuration. These complexes can be formally described as combination products of the stable neutral Fe(CO)₅ and cationic M(CO)₄⁺ fragments. Analyses based on canonical molecular orbitals, Mayer bond orders, and fragment-based correlation diagrams reveal the presence of a dative Fe→M interaction in FeM(CO)₉⁺, which formally enables the heavier Rh/Ir metal center to attain an 18-electron configuration. However, this bond is weaker than a typical covalent single bond, as the key molecular orbitals involved possess antibonding character. This study provides important insights into the structure and bonding of heteronuclear transition metal carbonyl clusters, highlighting distinctive coordination behavior between late 3d and heavier 4d/5d congeners. Full article

This study investigates particle size distribution and fine dust generation from sanding six tropical wood species (Red Meranti, Iroko, Zebrano, Bubinga, Ipe, and Wenge) using sieve analysis and laser diffraction. The wood species produced different dust particles, primarily influenced by wood density. Bubinga, Zebrano, and Wenge generated the highest proportion of particles in the 125–250 μm range, while Ipe and Iroko produced more dust in the 63–125 μm fraction. Low-density Red Meranti formed the greatest share of coarse particles (10.54% over 549.5 μm), whereas high-density Ipe generated the largest proportion of respirable dust, including PM₁₀ (8.80%), PM_2.5 (2.93%), and PM₁ (0.88%). Statistical analysis confirmed a significant effect of density on both coarse and fine dust fractions, with finer particles increasing consistently as density increased. Laser diffraction showed ultrafine particles down to approximately 0.7 μm in all species except Red Meranti. Microscopy confirmed elongated fibrous fragments, particularly in Wenge and Red Meranti. Overall, denser tropical hardwoods exhibited greater potential to produce hazardous fine dust during sanding, posing health risks and explosion hazards. These findings emphasize the need for effective dust extraction and high-efficiency respiratory protection and contribute to improved understanding of dust formation mechanisms in tropical wood processing. Full article

We report the fabrication of nanoscale MoS₂ (nMoS₂) via laser ablation in liquid and its application in electrochemical sensing. The laser ablation process fragments microscale MoS₂ sheets into ~5 nm dots with stable aqueous dispersibility. Electrochemical analysis reveals that nMoS₂ possesses multiple reversible redox states, enabling it to participate in redox cycling reactions that can amplify electrochemical signals. When the nMoS₂ is embedded in an electrochemically inert matrix, a chitosan layer, and subsequently incorporated within a nanostructured Au electrode, the nMoS₂-participating redox cycling reactions are further enhanced by the nanoconfinement effect, leading to synergistic signal amplification. As a model system, this hybrid nMoS₂-in-nanoporous Au electrode demonstrates a 9-fold increase in sensitivity for detecting pyocyanin, a biomarker of Pseudomonas aeruginosa infection, compared with a flat electrode without nMoS₂ loading. This study not only elucidates the redox characteristics of laser-fabricated zero-dimensional transition metal dichalcogenides but also presents a strategy to integrate semiconducting nanomaterials with metallic nanostructures for high-performance electrochemical sensing. Full article

Accurate and reliable extraction of building footprints from LiDAR point clouds is a fundamental task in remote sensing and urban scene reconstruction. Building footprints serve as essential geospatial products that support GIS database updating, land-use monitoring, disaster management, and digital twin development. Traditional image-based methods enable large-scale mapping but suffer from 2D perspective limitations and radiometric distortions, while airborne or vehicle-borne LiDAR systems often face single-viewpoint constraints that lead to incomplete or fragmented footprints. Recently, backpack mobile laser scanning (MLS) has emerged as a flexible platform for capturing dense urban geometry at the pedestrian level. However, the high noise, point sparsity, and structural complexity of MLS data make reliable footprints delineation particularly challenging. To address these issues, this study proposes a Deep Line-Segment Detection–Driven Building Footprints Extraction Framework that integrates multi-layer accumulated occupancy mapping, deep geometric feature learning, and structure-aware regularization. The accumulated occupancy maps aggregate stable wall features from multiple height slices to enhance contour continuity and suppress random noise. A deep line-segment detector is then employed to extract robust geometric cues from noisy projections, achieving accurate edge localization and reduced false responses. Finally, a structural chain-based completion and redundancy filtering strategy repairs fragmented contours and removes spurious lines, ensuring coherent and topologically consistent footprints reconstruction. Extensive experiments conducted on two campus scenes containing 102 buildings demonstrate that the proposed method achieves superior performance with an average Precision of 95.7%, Recall of 92.2%, F1-score of 93.9%, and IoU of 88.6%, outperforming existing baseline approaches by 4.5–7.8% in F1-score. These results highlight the strong potential of backpack LiDAR point clouds, when combined with deep line-segment detection and structural reasoning, to complement traditional remote sensing imagery and provide a reliable pathway for large-scale urban scene reconstruction and geospatial interpretation. Full article

Sensing represents one of the most rapidly developing areas of modern life sciences, spreading from the detection of pathogenic microorganisms in living systems, food, and beverages to hazardous substances in liquid and gaseous environments. However, the development of efficient and low-cost multimodal sensors with easy-to-read functionality is still very challenging. In this paper, stable aqueous colloidal suspensions (ζ-potential was between −30 and −40 mV) of ultrasmall (~7 nm) plasmonic Si-Au and SiC-Au nanocomposites were formed. Two variants of pulsed laser ablation in liquids (PLAL)—direct ablation and laser co-fragmentation—were used for this purpose. The co-fragmentation approach led to a considerable decrease in hydrodynamic diameter (~78 nm) and bandgap widening to approximately 1.6 eV. All plasmonic nanocomposites exhibited efficient multi-band blue emission peaking at ~430 nm upon Xe lamp excitation. Co-fragmentation route considerably (~1 order of magnitude) increased the PL efficiency of the nanocomposites in comparison with the laser-ablated ones, accompanied by a negligible amount of dangling bonds. These silicon-based nanostructures significantly affected the optical response of rhodamine 6G, depending on the synthesis route. In particular, directly ablated nanoparticles revealed a stronger influence on the optical response of dye molecules. The observed findings suggest using such types of semiconductor-plasmonic nanocomposites for multimodal plasmonic and colorimetric sensing integrated with luminescent detection capability. Full article