Search Results (883)

Linear array detector-based infrared push-broom imaging systems are widely employed in remote sensing and security surveillance due to their high spatial resolution, wide swath coverage, and low cost. However, the massive data volume generated during continuous scanning presents substantial storage and transmission challenges. To mitigate this issue, we propose a lossless compression algorithm based on pixel-adaptive prediction and hierarchical decomposition of residuals. The algorithm first performs pixel-wise adaptive noise compensation according to local image characteristics and achieves efficient prediction by exploiting the strong inter-pixel correlation along the scanning direction. Subsequently, hierarchical decomposition is applied to high-energy residual blocks to further eliminate spatial redundancy. Finally, the Golomb–Rice coding parameters are adaptively adjusted based on the neighborhood residual energy, optimizing the overall code length distribution. The experimental results demonstrate that our method significantly outperforms most state-of-the-art approaches in terms of both the compression ratio (CR) and bits per pixel (BPP). Moreover, while maintaining a CR comparable to H.265-Intra, our method achieves a 21-fold reduction in time complexity, confirming its superiority for large-format image compression. Full article

Several studies have demonstrated that methionine supplementation in fish diets enhances immune status, inflammatory response, and resistance to bacterial infections by modulating for DNA methylation, aminopropylation, and transsulfuration pathways. However, the immunomodulatory effects of methionine in viral infections remain unexplored. This study aimed to evaluate the effect of methionine supplementation on immune modulation and resistance to the viral haemorrhagic septicaemia virus (VHSV) in rainbow trout (Oncorhynchus mykiss). Two diets were formulated and fed to juvenile rainbow trout for four weeks: a control diet (CTRL) with all nutritional requirements, including the amino acid profile required for the species, and a methionine-supplemented diet (MET), containing twice the normal requirement of DL-methionine. After feeding, fish were bath-infected with VHSV, while control fish were exposed to a virus-free bath. Samples were collected at 0 (after feeding trial), 24, 72, and 120 h post-infection for the haematological profile, humoral immune response, oxidative stress, viral load, RNAseq, and gene expression analysis. In both diets, results showed a peak in viral activity at 72 h, followed by a reduction in viral load at 120 h, indicating immune recovery. During the peak of infection, leukocytes, thrombocytes, and monocytes migrated to the infection site, while oxidative stress biomarkers (superoxide dismutase glutathione S-transferase, and glutathione redox ratio) suggested a compromised ability to manage cellular imbalance due to intense viral activity. At 120 h, immune recovery and homeostasis were observed due to an increase in the amount of nitric oxide, GSH/GSSG levels, leukocyte replacement, monocyte influx, and a reduction in the viral load. When focusing on the infection peak, gene ontology (GO) analysis showed several exclusively enriched pathways in the skin and gills of MET-fed fish, driven by the upregulation of several key genes. Genes involved in recognition/signalling, inflammatory response, and other genes with direct antiviral activity, such as TLR3, MYD88, TRAF2, NF-κB, STING, IRF3, -7, VIG1, caspases, cathepsins, and TNF, were observed. Notably, VIG1 (viperin), a key antiviral protein, was significantly upregulated in gills, confirming the modulatory role of methionine in inducing its transcription. Viperin, which harbours an S-adenosyl-L-methionine (SAM) radical domain, is directly related to methionine biosynthesis and plays a critical role in the innate immune response to VHSV infection in rainbow trout. In summary, this study suggests that dietary methionine supplementation can enhance a more robust fish immune response to viral infections, with viperin as a crucial mediator. The improved antiviral readiness observed in MET-fed fish underscores the potential of targeted nutritional adjustments to sustain fish health and welfare in aquaculture. Full article

This study presents the first computational investigation of hybrid propeller configurations that combine toroidal and conventional blade geometries. Using Delayed Detached Eddy Simulation (DDES) with the Shear Stress Transport (SST) $k-\omega$ model for flow analysis and the Ffowcs Williams and Hawkings (FW–H) formulation for aeroacoustic prediction, five hybrid propeller designs were evaluated: a baseline model and four variants with modified loop-element spacing. The results show that the V-Gap-S configuration achieves the highest figure of merit (FM), producing over 10% improvement in propeller performance relative to the baseline, while also exhibiting the lowest turbulence kinetic energy (TKE) levels across multiple radial planes. Aeroacoustic analysis reveals quadrupole-like directivity for primary tonal noise, primarily driven by blade tip–vortex interactions, with primary tonal noise strongly correlated with thrust. Broadband noise and overall sound pressure level (OASPL) exhibited dipole-like patterns, influenced by propeller torque and FM, respectively. Comparisons of surface pressure, vorticity, and time derivatives of acoustic pressure further elucidate the mechanisms linking blade spacing to aerodynamic loading and noise generation. The results demonstrate that aerodynamic performance and aeroacoustics are strongly coupled and that meaningful noise reduction claims require performance conditions to be matched. Full article

Decarbonization of compression-ignition engines requires evaluation of carbon-free and low-carbon fuel alternatives. Ammonia (${NH}_3$) offers zero direct carbon emissions but faces combustion challenges including low flame speed (7 $\mathrm{c}\mathrm{m}/\mathrm{s}$) and high auto-ignition temperature (657 °$\mathrm{C}$). Methanol provides improved reactivity and bound oxygen content that can enhance ignition characteristics. This computational study investigates diesel–ammonia–methanol ternary fuel blends using validated three-dimensional CFD simulations (ANSYS Forte 2023 R2; ANSYS, Inc., Canonsburg, PA, USA) with merged chemical kinetic mechanisms (247 species, 2431 reactions). The model was validated against experimental in-cylinder pressure data with deviations below 5% on a single-cylinder diesel engine (510 cm³, 17.5:1 compression ratio, 1500 rpm). Ammonia energy ratios were systematically varied (10–50%) with methanol substitution levels (0–90%). Fuel preheating at 530 K was employed for high-alcohol compositions exhibiting ignition failure at standard temperature. Results demonstrate that peak cylinder pressures of 130–145 bar are achievable at 10–30% ammonia with M30K–M60K configurations, comparable to baseline diesel (140 bar). Indicated thermal efficiency reaches 38–42% at 30% ammonia-representing 5–8 percentage point improvements over diesel baseline (31%)-but declines to 30–32% at 50% ammonia due to fundamental combustion limitations. ${CO}_2$ reductions scale approximately linearly with ammonia content: 35–55% at 30% ammonia and 75–78% at 50% ammonia. ${NO}_X$ emissions demonstrate 30–60% reductions at efficiency-optimal configurations. Multi-objective optimization analysis identifies the A30M60K configuration (30% ammonia, 60% methanol, 530 K preheating) as optimal, achieving 42% thermal efficiency, 58% ${CO}_2$ reduction, 51% ${NO}_X$ reduction, and 11% power enhancement versus diesel. This configuration occupies the Pareto frontier “knee point” with cross-scenario robustness. Full article

To address the severe wear of the hole wall and orifice in ejector pin guide holes of injection molds caused by frequent hole-shaft sliding, this study proposes a composite strengthening method that combines nitriding with oblique laser shock peening (N-OLSP). The strengthening uniformity in both circumferential and axial directions was evaluated by defining a laser shock peening uniformity coefficient ($k$). By strictly controlling the uniformity coefficient ratio of two adjacent spots to be no less than 0.98, the optimal step angles for circumferential and axial directions were determined. Comparative experiments were conducted on three types of samples: Untreated, Nitrided, and N-OLSP treated. The results demonstrate that N-OLSP significantly enhances both surface hardness and residual compressive stress of the guide hole, and the degree of improvement increases with a higher value of $k$. Among the tested samples, N-OLSP exhibited the best wear resistance at the orifice, reducing the wear rate to 0.60 μm/h. Compared with the untreated and nitrided samples, the wear rate reduction achieved by N-OLSP was 66.85% and 16.67%, respectively. Full article

Magnesium phosphate cement (MPC) holds great potential for rapid repairs, yet its practical application is limited by its intense hydration exotherm. While many existing studies confirm paraffin (PA)’s ability to regulate hydration heat in other cement-based materials, the comparison of hydration heat regulation efficacy among PAs with different phase change temperatures and the accompanying performance trade-offs in MPC systems remain insufficiently explored. This study comprehensively evaluates the effects of three PAs with distinct phase change characteristics (n-C18, n-C20, n-C22) and their contents on the hydration heat regulation and performance of MPC. Direct incorporation of PAs was adopted to assess its practical feasibility, considering construction cost-effectiveness. Investigations were conducted using hydration heat release tests, temperature rise monitoring, DSC, mechanical tests, XRD, and SEM. Results show that all PAs significantly retarded heat release and suppressed temperature rise, with efficacy increasing with phase change temperature; a maximum exothermic peak reduction of 64% was achieved with 4% n-C22. PAs also introduced distinct temperature plateaus near their phase change temperature, further enhancing temperature regulation. As a key trade-off, compressive strength decreased with increasing PA content, but mixtures with n-C18 ≤ 8%, n-C22 ≤ 4%, and n-C20 = 2% still met the standard strength requirement for rapid repair, 3 h compressive strength ≥ 20 MPa. Microstructural analysis reveals that while regulating hydration heat, PA also hindered the hydration product formation and crystallization, underpinning the observed performance trade-offs. This study establishes a clear performance correlation between PAs with different phase change temperatures and MPC, clarifies the intrinsic trade-offs between heat regulation and mechanical properties, and offers actionable guidance for engineering applications—facilitating the development of high-performance PA/MPC composites with controllable heat release for rapid repair scenarios. Full article

Hydrogen-based direct reduction (H-DR) represents an environmentally benign and energy-efficient alternative in ironmaking that has significant industrial potential. This study reviews the current status of H-DR shaft furnaces and accompanying hydrogen-rich reforming technologies (steam and autothermal reforming), assessing the three dominant numerical frameworks used to analyze these processes: (i) porous medium continuum models, (ii) the Eulerian two-fluid model (TFMs), and (iii) coupled computational fluid dynamics (CFD)–discrete element method (DEM) models. The respective trade-offs in terms of computational cost and model accuracy are critically compared. Recent progress is evaluated from an engineering standpoint in four key areas: optimization of the pellet bed structure and gas distribution, thermal control of the reduction zone, sensitivity analysis of operating parameters, and industrial-scale model validation. Current limitations in predictive accuracy, computational efficiency, and plant-level transferability are identified, and possible mitigation strategies are discussed. Looking forward, high-fidelity multi-physics coupling, advanced mesoscale descriptions, AI-accelerated surrogate models, and rigorous uncertainty quantification can facilitate effective scalable and intelligent application of hydrogen-based shaft furnace simulations. Full article

The frictional resistance of impeller machinery blades such as aircraft engines, gas turbines, and wind turbines has a decisive impact on their efficiency and energy consumption. Inspired by the micro-tooth structure on the surface of shark skin, microstructural drag reduction technology has become a cutting-edge research direction for improving aerodynamic performance and a continuous focus of researchers over the past 20 years. However, the significant difficulty in fabricating microstructures on three-dimensional curved surfaces has led to the limited widespread application of this technology in engineering. Addressing the issue of drag reduction and efficiency improvement for small axial flow fans (local Reynolds number range: (36,327–40,330), this paper employs Design of Experiments (DOE) combined with high-precision numerical simulation to clarify the drag reduction law of bionic microgroove surfaces and determine the dimensions of bionic microstructures on fan blade surfaces. The steady-state calculation uses the standard k-ω model and simpleFoam solver, while the unsteady Large Eddy Simulation (LES) employs the pimpleFoam solver and WALE subgrid-scale model. The dimensionless height (h⁺) and width (s⁺) of microgrooves are in the range of 8.50–29.75, and the micro-grooved structure achieves effective drag reduction. The microstructured surface is fabricated on the suction surface of the blade via a spray coating process, and the dimensions of the microstructures are determined according to the drag reduction law of grooved flat plates. Aerodynamic performance tests indicate that the shaft power consumed by the bionic fan blades during the tests is significantly reduced. The maximum static pressure efficiency of the bionic fan with micro-dimples is increased by 2.33%, while that of the bionic fan with micro-grooves is increased by 3.46%. The fabrication method of the bionic microstructured surface proposed in this paper is expected to promote the engineering application of bionic drag reduction technology. Full article

Introduction: Severe acute pancreatitis (SAP) is a critical condition that affects 20–30% of people with acute pancreatitis (AP). Prompt detection and accurate classification are crucial to direct prompt interventions, increase resource allocation, and improve patient outcomes. Current scoring systems, while beneficial, frequently face challenges related to speed, complexity, and early predictive accuracy. Method: We developed and validated an effective six-parameter risk assessment scale for AP, incorporating pancreatic-specific biomarkers (trypsinogen-activating peptide [TAP], trypsin-2), systemic inflammation markers (C-reactive protein), pancreatic enzyme concentrations, blood glucose, and patient age. The study cohort included 104 patient samples. Reliability was assessed using Cronbach’s alpha and Spearman–Brown coefficients, factorial validity was determined by principal component analysis, and predictive validity was analyzed using logistic regression and receiver operating characteristic (ROC) analysis. Biotemporal changes at 24 and 48 h were assessed to classify risk scoring. Results: The scale demonstrated satisfactory internal consistency (Cronbach’s alpha = 0.72) and a distinct structure with two factors representing local pancreatic damage and systemic inflammation, explaining 65% of the variability. Logistic regression established predictive validity for serious outcomes, with TAP and trypsin-2 showing significant correlations. ROC analysis demonstrated remarkable discriminative capacity (AUC = 0.85), showing a sensitivity of 82.4% and a specificity of 76.8%. Assessment of temporal biomarkers showed a reduction in TAP, signifying resolution of the initial enzymatic activation, while trypsin-2 levels continued to increase, indicating persistent damage to the pancreatic tissue. Patients were classified into low-, moderate- and high-risk groups, facilitating practical clinical decision-making. Discussion and Conclusions: This six-parameter risk score provides a rapid, biologically based, and clinically useful method for early detection of patients at risk for SAP. Combining indicators of local pancreatic involvement with systemic inflammation allows for prompt triage, improves the allocation of intensive therapy, and supports informed prognostic conversations. Full article

The exceptional catalytic efficiency of [FeFe]-hydrogenases has driven intense efforts to reproduce their structure and function in synthetic models. A key structural feature governing the behavior of synthetic H-cluster analogs lies in the identity of the bridging dithiolato ligands that link the iron centers. These ligands play a pivotal role in tuning the electron density of the metal core, thereby dictating the complex’s redox characteristics and catalytic reactivity. In this context, we herein describe the synthesis and application of ferrocenyl bithiophene-2,2′-yl thioketone (1) as a proligand for assembling biomimetic models of the [FeFe]-hydrogenase active site. The obtained complexes were thoroughly examined using a suite of analytical methods, including NMR and IR spectroscopy, elemental analysis, and a single-crystal X-ray diffraction, affording comprehensive structural and chemical characterization. Furthermore, their electrochemical behavior toward proton reduction and hydrogen evolution was evaluated via cyclic voltammetry, enabling direct comparison with structurally related analogs. Full article

Construction progress monitoring remains predominantly manual, labor-intensive, and reliant on subjective human interpretation. Human dependence often leads to redundant or unreliable information, resulting in scheduling delays and increased costs. Advances in drones, point cloud generation, and multisensor data acquisition have expanded access to high-resolution as-built data. However, transforming data into reliable automated indicators of progress poses a challenge. A limitation is the lack of robust material-level segmentation, particularly for structural materials such as concrete and steel. Concrete and steel are crucial for verifying progress, ensuring quality, and facilitating construction management. Most studies in point cloud segmentation focus on object- or scene-level classification and primarily use geometric features, which limit their ability to distinguish materials with similar geometries but differing physical properties. A consolidated and systematic understanding of the performance of multispectral and multimodal segmentation methods for material-specific classification in construction environments remains unavailable. The systematic review addresses the existing gap by synthesizing and analyzing literature published from 2020 to 2025. The review focuses on segmentation methodologies, multispectral and multimodal data sources, performance metrics, dataset limitations, and documented challenges. Additionally, the review identifies research directions to facilitate automated progress monitoring of construction and to enhance digital twin frameworks. The review indicates strong quantitative performance, with multispectral and multimodal segmentation approaches achieving accuracies of 93–97% when integrating spectral information into point cloud or image-based pipelines. Large-scale environments benefit from combined LiDAR and high-resolution imagery approaches, which achieve classification quality metrics of 85–90%, thereby demonstrating robustness under complex acquisition conditions. Automated inspection workflows reduce inspection time from 24 h to less than 2 h and yield cost reductions of more than 50% compared to conventional methods. Additionally, deep-learning-based defect detection achieves inference times of 5–6 s per structural element, with reported accuracies of around 97%. The findings confirm productivity gains for construction monitoring. Full article

Recently, the kinetic improvement of the nitrogenation reaction of lithium hydride (LiH) to form lithium imide (Li₂NH) by adding a scaffold was reported. The scaffold prevents agglomeration of Li₂NH and maintains the activity of LiH, achieving a reduction in reaction temperature and an increase in reaction rate. In this work, a Li–Si alloy, Li₂₂Si₅, was used as a starting material to form nano-sized LiH dispersed in a Li alloy matrix. Lithium nitride (Li₃N) is generated by the reaction between Li₂₂Si₅ and N₂ to form Li₇Si₃, and then Li₃N is converted to LiH with ammonia (NH₃) generation during heat treatment under H₂ flow conditions. Since Li₃N is formed at the nano-scale on the surface of alloy particles, LiH generated from the above nano-Li₃N is also nano-scale. The differential scanning calorimetry results indicate that direct nitrogenation of LiH in the alloy matrix occurred from around 280 °C, which is much lower than that of the LiH powder itself. Such a highly active state might be achieved due to the nano-crystalline LiH confined by the Li alloy as a self-transformed scaffold. From the above experimental results, the nano-confined LiH in the alloy matrix was recognized as a potential NH₃ synthesis technique based on the LiH-Li₂NH type chemical looping process. Full article

This study describes an optimized plastic surface-based capsid protein adsorption/capturing method for detection of cowpea mild mottle virus (CPMMV) adapted from the direct antigen-capture method reported for the extraction of rose rosette virus (RRV) and other direct virus capturing attempts. Briefly, the method starts with sap incubation, removal of unbound residual tissue and inhibitors by washing, and the viral RNA release using nuclease-free water and heat, in the presence of an RNase inhibitor. The protocol’s efficiency was assessed across different pH conditions, RNaseOUT concentrations, and reverse-transcriptase choices, and its performance was compared with commercial RNA-extraction methods. Three hundred thirty-two positive samples for CPMMV were processed using the optimized protocol (PBS-T, pH 7.4; RNaseOUT at 0.5 U/µL; and M-MLV reverse transcriptase). RT-PCR detection results were consistent with those obtained using the standard method. Cost estimates for tissue trapping indicate reductions of approximately 70% and 90% compared with the Qiagen RNeasy kit (Qiagen, Hilden, Germany) and the Bertheau method, respectively. The tissue-absorption protocol combines simplicity and low cost, making it particularly well suited for field diagnostics; by enabling rapid recovery of viral RNA without commercial kits and substantially reducing processing steps, it represents a practical, cost-effective alternative for routine CPMMV testing. Full article

The rhenium(I) tricarbonyl complex fac-[Re(CO)₃(5,6-epoxy-5,6-dihydro-1,10-phenanthroline)Br] (ReL) has previously demonstrated promising luminescent properties, enabling its direct application as a probe for walled cells such as Candida albicans and Salmonella enterica. In this new study, we present a significantly expanded and comprehensive characterization of ReL, incorporating a wide range of experimental and computational techniques not previously reported. These include variable-temperature ¹H and ¹³C NMR spectroscopy, CH-COSY, single-crystal X-ray diffraction, Hirshfeld surface analysis, DFT calculations, Fukui functions, non-covalent interaction (NCI) indices, and electrochemical profiling. Structural analysis confirmed a pseudo-octahedral geometry with the bromide ligand positioned cis to the epoxy group. NMR data revealed the coexistence of cis and trans isomers in solution, with the trans form being slightly more stable. DFT calculations and aromaticity descriptors indicated minimal electronic differences between isomers, supporting their unified treatment in subsequent analyses. Electrochemical studies revealed two oxidation and two reduction events, consistent with ECE and EEC mechanisms, including a Re(I) → Re(0) transition at −1.50 V vs. SCE. Theoretical redox potentials showed strong agreement with experimental data. Biological assays revealed a dose-dependent cytotoxic effect on HeLa cells, contrasting with previously reported low toxicity in microbial systems. These findings, combined with ReL’s luminescent and antimicrobial properties, underscore its multifunctional nature and highlight its potential as a bioactive and imaging agent for advanced therapeutic and microbiological applications. Full article

Synthetic cathinones such as 3,4-methylenedioxypyrovalerone (MDPV) are potent psychostimulants with high abuse potential, yet their systemic toxicity and neurobehavioral effects remain poorly characterized during early development. Using Danio rerio (zebrafish) embryos and larvae, we performed an integrated assessment of the cardiotoxic, behavioral, and molecular effects of MDPV. Acute exposure of 3 days post-fertilization (dpf) embryos produced a marked, concentration-dependent bradycardia and atrioventricular (AV) conduction block, leading to reduced ventricular activity and complete AV dissociation at the highest concentrations (EC₅₀ = 228 µM). Quantitative analysis of ventricular motion revealed a significant decrease in cardiac output (CO) at all tested concentrations and a reduction in ejection fraction (EF) only at 480 µM, while fractional shortening (FS) and stroke volume (SV) remained unchanged, indicating predominant chronotropic and conduction effects with secondary contractile impairment. In 5 dpf larvae, MDPV caused a sustained, concentration-dependent decrease in basal locomotor activity (EC₅₀ = 2.51 µM) but did not affect prepulse inhibition (PPI) of the acoustic startle response (ASR), unlike dextroamphetamine, which enhanced PPI via dopaminergic D₂ receptor activation. Short-term (2 h) exposure of 3 dpf embryos to 0.4–400 µM MDPV induced transcriptional changes in dopaminergic and stress-responsive genes, whereas expression of major repolarizing potassium channel genes (kcnh6a and kcnq1) remained unaltered. Collectively, these results demonstrate that MDPV exerts potent negative chronotropic effects likely through direct functional interference with cardiac repolarization, while neurobehavioral effects occur at concentrations nearly two orders of magnitude lower than cardiotoxic thresholds, supporting zebrafish as a predictive model for the integrative assessment of psychostimulant toxicity. Full article