Search Results (12,331)

Municipal sewage sludge represents a significant environmental challenge due to its large-scale production and limited disposal options. Pyrolysis, a thermal decomposition process, offers a promising approach for converting sewage sludge into biochar, a carbon-rich material with diverse environmental applications. Sewage sludge-derived biochars were prepared at pyrolysis temperatures of 300 °C, 500 °C, 700 °C, and 900 °C (denoted as B300 to B900) and evaluated for their structural, adsorption, and catalytic performance. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET), and energy dispersive X-ray spectrometry (EDS) analyses revealed a distinct temperature-dependent morphological evolution and mineral exposure. The B900 biochar exhibited a BET surface area of 83.8 m²/g and the highest pore volume of 0.101 cm³/g, indicating a well-developed mesoporous structure. In catalytic degradation tests using 20 mg/L persulfate and 500 mg/L B900, rapid oxidation was observed, achieving 91% methylene blue (MB) degradation in 30 min, highlighting its role in activating persulfate via surface-bound Fe and Al species. Optimization studies confirmed that MB removal efficiency was highest at 500 mg/L biochar and 40 mg/L persulfate, and the system was not significantly affected by the tap and synthetic wastewater matrices. This work demonstrates that biochar obtained from sewage sludge can serve as an eco-friendly and multifunctional material for resource recovery and environmental cleanup. Full article

Background/Objectives: Upper limb amputation presents considerable physical and psychological challenges, especially in young, active individuals. This case study outlines the rehabilitation journey of a 33-year-old patient, an Italian national Paralympic snowboard cross athlete, who underwent elective transradial amputation followed by advanced surgical and prosthetic interventions. The objective was to assess the combined impact of upper limb Targeted Sensory Reinnervation (ulTSR) and the Adam’s Hand prosthetic system on functional recovery and user satisfaction. Methods: After a partial brachial plexus injury caused complete paralysis of his right hand, the patient opted for transradial amputation. He subsequently underwent ulTSR, performed by plastic surgeon, Alexander Gardetto, MD, which involved rerouting sensory nerves to defined regions of the residual limb in order to reestablish a phantom limb map. This reinnervation was designed to facilitate improved prosthetic integration. The Adam’s Hand, a myoelectric prosthesis with AI-based pattern recognition, was selected for its compatibility with TSR and intuitive control. Outcomes were evaluated using the OPUS questionnaire, the DASH, and patient feedback. Results: ulTSR successfully restored meaningful sensory input, allowing intuitive and precise control of the prosthesis, with minimal cognitive and muscular effort. The patient regained the ability to perform numerous activities of daily living such as dressing, eating, lifting, and fine motor tasks—which had been impossible for over 15 years. OPUS results demonstrated significant improvements in both function and satisfaction. Conclusions: This case highlights the synergistic benefits of combining ulTSR with user-centered prosthetic technology. Surgical neurorehabilitation, paired with advanced prosthetic design, led to marked improvements in autonomy, performance, and quality of life in a high-performance amputee athlete. Full article

Background: Problematic overstudying has been conceptualized as an addictive behavior (study addiction) and an early form of work addiction. The majority of students showing compulsive studying behaviors experience chronic and high stress and symptoms of generalized anxiety disorder. Caffeine is a widely used stimulant that enhances alertness and cognitive performance, especially under fatigue. University students, particularly those exhibiting problematic overstudying, may consume more caffeine to improve academic performance. Previous research has shown that caffeine consumption is positively associated with perceived stress and anxiety. This study examined the mediating role of caffeine consumption in the relationship between problematic overstudying and psychological distress (perceived stress, anxiety, and depression) among university students. Methods: Sample 1 consisted of 436 university students, and Sample 2 included 3421 students. The Bergen Study Addiction Scale, Perceived Stress Scale-4, and a measure of average daily caffeine consumption were used. Results: Results showed that caffeine consumption partially mediated the relationship between problematic overstudying and perceived stress. Students who study compulsively tended to consume more caffeine, which was, in turn, associated with higher perceived stress. This finding was replicated across both samples, and in the second, larger sample, caffeine intake also mediated between problematic overstudying and anxiety and depression. Conclusions: Excessive caffeine use among students who manifest problematic overstudying may increase their risk of developing, or aggravate existing, symptoms of anxiety or mood disorders. Limiting caffeine intake and promoting healthy alternatives, such as rest and recovery, is recommended to support mental health in this population. Full article

For the first time, an alternative and sustainable approach is reported using phenyl-2-pyridyl ketoxime (PPKO) as a selective extracting agent for the recovery of Cu(II) from alkaline solutions in the presence of tartrate ions. The advantages relative to conventional processes carried out in acidic media are outlined. Through potentiometric and spectrophotometric analyses, the sequential formation of a 1:2 metal cation–ligand Cu(II)-(PPKO)₂ complex was identified as the predominant species in alkaline aqueous solutions. The high removal capacity of the extractant for Cu(II), as assessed from liquid–liquid extraction, and its efficient performance are comparable to widely used commercial extractants. Thermodynamic studies of the complexation between the copper(II) ion and PPKO demonstrated that the process exhibits an endothermic character. A progressive decrease in the performance of the extractant was observed after reuse without a regenerative treatment. This deterioration was partially reversed through a controlled reprotonation process using an acetate buffer solution. Overall, the results support the potential of PPKO as an effective and selective alternative ligand for hydrometallurgical applications in alkaline medium. Full article

Globally, winery wastewaters (WWWs) are estimated to account for about 62.5 billion L annually (2021), with COD levels up to 300,000 mg O₂/L primarily attributed to residual ethanol, posing serious environmental concerns. Conventional treatments are effective in COD removal, but they often miss opportunities for energy recovery and resource valorization. This study investigates the aqueous phase reforming (APR) of ethanol-rich wastewater as an alternative treatment for both COD reduction and energy generation. Two scenarios were assessed: electricity and heat cogeneration (S1) and hydrogen production (S2). Process simulations in Aspen Plus^® V14, based on lab-scale APR data, provided upscaled material and energy flows for techno-economic analysis, life cycle assessment, and energy sustainability analysis of a 2.5 m³/h plant. At 75% ethanol conversion, the minimum selling price (MSP) was USD0.80/kWh with a carbon footprint of 0.08 kg CO₂-eq/kWh for S1 and USD7.00/kg with 2.57 kg CO₂-eq/kg H₂ for S2. Interestingly, S1 revealed a non-linear trade-off between APR performance and energy integration, with higher ethanol conversion leading to a higher electricity selling price because of the increased heat reactor duty. In both cases, the main contributors to global warming potential (GWP) were platinum extraction/recovery and residual COD treatment. Both scenarios achieved a positive energy balance, with an energy return on investment (EROI) of 1.57 for S1 and 2.71 for S2. This study demonstrates the potential of APR as a strategy for self-sufficient energy valorization and additional revenue generation in wine-producing regions. Full article

Background: While mechanical alignment total knee arthroplasty (TKA) has long been the conventional surgical technique in patients with advanced osteoarthritis, kinematic alignment TKA has emerged as a promising alternative, designed to restore the knee’s native pre-arthritic anatomy. Since superiority of either technique remains inconclusive, we aimed to compare immediate and short-term postoperative outcomes of kinematic versus mechanical alignment TKA. Methods: This prospective cohort study was conducted at a tertiary care centre between January 2020 and August 2022, enrolling kinematic and mechanical alignment TKA patients. Outcomes were assessed during hospitalization and at 14 days postoperatively. Data collected included patient-reported outcome measures (PROMs), functional performance evaluations, pain scores, discharge disposition and hospital length of stay. Both univariate and multivariate regression analyses were conducted, adjusting for potential confounders. Results: The study included 103 patients, with 77 who underwent kinematic alignment and 26 mechanical alignment TKA. Patients in the kinematic alignment group demonstrated statistically significant better postoperative outcomes compared to those in the mechanical alignment group. Kinematic alignment TKA patients demonstrated superior functional performance on the Timed Up and Go test immediately postoperatively and were more frequently discharged home rather than to a rehabilitation facility. Hospital stay length and short-term PROMs also favoured the Kinematic alignment TKA group, showing statistically significant higher scores in the Oxford Knee Score, short form-12 Mental Component Summary, and the Knee Injury and Osteoarthritis Outcome Score Symptoms subscale. Conclusions: Kinematic alignment TKA offers superior immediate and short-term outcomes compared to mechanical alignment TKA, with benefits in functional recovery, hospitalization duration, and discharge disposition. This evidence supports kinematic alignment TKA as a viable alternative, aiding in patient and surgeon decision-making. Full article

Elevated phosphorus levels in wastewater created significant environmental concerns, including the degradation of surrounding soil structure, inhibition of plant growth, and potential threats to human health. To address this issue, a self-standing nanofibrous composite membrane based on PA-66/PVA-15%La(OH)₃ was fabricated via electrospinning, followed by glutaraldehyde (GA) crosslinking and alkali hydrolysis to create an interpenetrating structure, where PA-66 provided the overall mechanical strength of the membrane, while La served as a functional component for the adsorption of phosphate. The chemical composition, surface morphology, thermal stability, and mechanical properties of the resulting membranes were characterized using ATR-FTIR, SEM, TGA, and tensile testing, respectively. Furthermore, the adsorption performance of the membranes was evaluated systematically through static and dynamic adsorption. The Langmuir isotherm model yielded a theoretical maximum adsorption capacity of 21.39 mg/g for phosphate ions. Notably, over 96% of this capacity was retained even in the presence of interfering ions. Moreover, dynamic adsorption experiments demonstrated that the membrane can deal with 1.74 L of phosphate-containing wastewater at a low flow rate of 1.0 mL/min and 1.46 L at a high flow rate of 2.0 mL/min, respectively, while consistently maintaining a phosphate removal efficiency exceeding 90%. A controlled release of phosphate ions from a phosphate-adsorbed membrane was successfully demonstrated using Mougeotia cultivation, implying the potential for phosphorus resource recovery. Full article

With the continuous increase in renewable energy penetration, traditional frequency regulation strategies in power grids struggle to maintain frequency stability under high renewable-share conditions. To address the shortcomings of the current deadband settings in regional grid frequency regulation, this paper proposes an optimized deadband-configuration scheme for renewable energy power plants and evaluates its effectiveness in enhancing the frequency regulation potential of renewable units. By developing frequency response models for thermal power, wind power, photovoltaic generation, and energy storage, the impact of different deadband widths on dynamic frequency response and steady-state deviation is analyzed. Three representative output scenarios for renewable units are constructed, and under each scenario the coordinated control performance of the proposed and the existing deadband configurations is compared. Simulation studies are then conducted based on a typical high renewable penetration scenario. The results show that, compared with the existing regional-grid deadband settings, the proposed configuration more fully exploits the regulation potential of renewable units, improves overall frequency-response capability, significantly reduces frequency deviations, and shortens recovery time. This research provides both theoretical foundations and practical guidance for frequency-support provision by renewable energy power plants under high penetration conditions. Full article

Additive manufacturing (AM) via selective laser melting (SLM) is increasingly deployed in aerospace, biomedical, and tooling applications where complex geometries and high performance are required. Yet, process-induced anisotropy and microstructural heterogeneity can strongly affect mechanical and tribological behavior. This study systematically evaluates the combined effects of build orientation (0°, 45°, and 90° relative to the build plate) and post-build heat treatment (as-built, 600 °C, and 860 °C) on the phase constitution, microstructure, hardness, tensile response, and dry sliding wear of SLM-fabricated 316L stainless steel. X-ray diffraction indicated a fully austenitic (γ-fcc) structure without detectable secondary phases across all conditions. Orientation-dependent substructures were observed: ~1 µm equiaxed cellular features at 0°, finer 0.3–0.5 µm cells at 45°, and 1–2 µm elongated features at 90°. Microhardness varied with orientation; relative to 0°, 45° specimens were ~15 HV higher, whereas 90° specimens were ~10 HV lower. Heat treatment at 600 °C promoted refinement and recovery of the cellular network, most pronounced in the 45° orientation, while treatment at 860 °C largely erased melt pool boundary contrast, producing a more homogeneous particle-like microstructure. Tensile fractography revealed dimpled rupture in all cases; the 90° orientation showed finer dimples and lower hardness, consistent with a ductile failure mode under reduced constraint. Dry sliding wear tests identified adhesive wear, intensified by the build-up of transferred fragments, as the dominant mechanism in both as-built and 600 °C conditions. Changes to melt pool morphology after 860 °C heat treatment correlated with altered wear track widths, with the 0° condition showing a notable narrowing relative to the 600 °C state. These results highlight processing pathways for tailoring anisotropy, strength–ductility balance, and wear resistance in SLM 316L. Full article

Extensive studies have established that ultrasonic micro-jets and acoustic cavitation selectively intensify interfacial interactions at multiphase boundaries, thereby enhancing the flotation of soluble salt minerals and oxide ores. Although a growing body of evidence shows that pulp-borne nanoparticles (i.e., nanosolids, colloids, and nanoscale gas nuclei) mediate these effects, their role in the flotation of ultrafine smithsonite after collector addition has not yet been systematically examined. To fill this gap, we compared the flotation response of ultrafine smithsonite under conventional stirring (SC) and ultrasonic conditioning (UC), using sodium oleate (NaOL) as the collector, and dissected the governing mechanisms across three pillars, mineral–NaOL interaction, particle aggregation, and frothability, with particular attention paid to how nanoparticles modulate each dimension. The flotation results show that flotation performance under UC is dictated by NaOL concentration. At low NaOL levels (i.e., below 4 × 10⁻⁴ M), UC depresses both recovery and kinetics relative to SC, while at high NaOL levels, the trend reverses and UC outperforms SC. Mechanistic analysis reveals that sonication erodes mineral surfaces and generates cavitation, flooding the pulp with various nanoparticles. When NaOL is scarce, zinc-containing components and zinc-rich nanosolids sequester the collector through non-selective adsorption and precipitation, leaving smithsonite poorly hydrophobized. Consequently, particle aggregation and pulp frothability are markedly inferior to those in the SC system, so the flotation recovery and kinetics remain lower. As the NaOL concentration rises, smithsonite becomes adequately hydrophobized, and the pulp fills with hydrophobic zinc-rich nanosolids, along with cavitation-induced gas nuclei or tiny bubbles. These nanoparticles now act as bridges, accelerating the aggregation of ultrafine smithsonite once sonication stops and agitation begins, while simultaneously improving frothability. Although the strong dispersive action of ultrasound still suppresses initial flotation kinetics, cumulative recovery ultimately surpasses that of SC. The findings delineate a nanoparticle-regulated flotation paradigm and establish a critical NaOL concentration window for effective UC in ultrafine smithsonite flotation. This framework is readily transferable to the beneficiation of other ultrafine, soluble oxidized minerals (rhodochrosite, dolomite, etc.). Full article

Quantitative determination of calcium content in milk and dairy products is an important analytical task due to the great importance of this element in the human diet. Calcium determination in milk and dairy products was performed using semi-automatic complexometric titration with a webcam as a color change detector. The color changes were registered directly in turbid dairy dispersions, creating a white background. The analytical signals tested were the color component (R, G, B) read from the titration beaker images and the calculated Hue parameter. For the calcein indicator, the optimal signals are Green and Hue. For the HNB indicator, the optimal signals are Red and Hue. The developed method of titration using an RGB camera detector is characterized by excellent linearity (R² = 0.9999) and accuracy. RSD values range from 0.3 to 2.9%. Recovery values range from 105 to 113%. Examples of calcium determination in commercial products include milk, fermented products, cream, and cottage cheese. Full article

Background: Efficient and safe discharge is critical in pediatric dental procedures performed under deep sedation in non-operating room anesthesia (NORA) settings. Traditional institutional criteria may delay discharge due to subjectivity. Objective: This study compared the Modified Aldrete Recovery Score (MAS) and institutional discharge criteria to determine which provides faster and reliable discharge decisions. Methods: In this prospective observational study, 100 children (ages 2–10, ASA I–III) undergoing deep sedation for dental treatment were evaluated. Two nurse anesthetists independently assessed discharge readiness every five minutes using either MAS or institutional criteria. Demographic data, BMI percentile, ASA class, anesthesia duration, and propofol dose were recorded. Discharge times were compared using Wilcoxon signed-rank and subgroup analyses and correlation tests. Results: MAS allowed significantly earlier discharge than institutional criteria (24.75 ± 7.33 vs. 36.79 ± 8.59 min, p = 0.01). The agreement between methods was poor (ICC = 0.06). Discharge time varied significantly by BMI percentile (p = 0.01); obese children had shorter recovery times, while time differences were greater in overweight children. No adverse events or readmissions occurred. Conclusions: MAS provides a quicker and equally safe discharge assessment in pediatric dental sedation. Its use may enhance workflow efficiency and standardize recovery decisions in NORA settings lacking formal PACUs. Full article

Background/Objectives: Nanobubble water (NBW) is being studied increasingly for its potential benefits in sports nutrition. This study aimed to evaluate whether supplementation with ozone-enriched NBW (O₃-NBW) could improve integrated exercise capacity—encompassing endurance performance, muscle strength, and postexercise recovery as well as body composition and metabolic adaptations in mice. Methods: Male ICR mice (n = 24) were allocated into Control, Air-NBW, or O₃-NBW (0.2–1 mg/L ozone) groups for 4 weeks. Results: O₃-NBW treatment considerably enhanced forelimb grip strength and treadmill running endurance compared to the Control group (both p < 0.05). Analyses of body composition revealed a higher proportion of lean mass and muscle glycogen storage in NBW groups, notably with O₃-NBW. Serum markers gathered post-exercise demonstrated a reduction in ammonia and blood urea nitrogen (BUN), suggesting improved nitrogen metabolism. Levels of resting serum creatine kinase (CK) and uric acid were also lower in O₃-NBW mice, indicating potential benefits for muscle recovery. In addition, O₃-NBW treatment significantly enhanced oxygen consumption (VO₂) and reduced the respiratory quotient (RQ), signifying amplified fat oxidation, while also lowering total energy expenditure (all p < 0.05). Spontaneous wheel-running activity remained consistent across all the groups. Conclusions: Taken as a whole, these findings emphasize that O₃-NBW supplementation offers ergogenic and metabolic advantages by improving integrated exercise capacity and efficiency of gas exchange, without adverse effects. Full article

This paper presents an efficient U-Net architecture featuring a modified Global Local Former Block (mGLFB) for simultaneous speech denoising and resolution reconstruction. Optimized for computational efficiency in the discrete cosine transform domain, the proposed architecture reduces model size by 13.5% compared to a standard GLFB-based U-Net, while maintaining comparable performance across multiple quality metrics. In addition to the mGLFB redesign, we introduce a perceptual loss that better captures high-frequency magnitude spectra, yielding notable gains in high-resolution recovery, especially in unvoiced speech segments. However, the mGLFB-based U-Net still shows limitations in retrieving spectral details with substantial energy in 4–6 kHz frequencies. Full article

Brine with a high magnesium-to-lithium ratio was separated by electrodialysis equipped with a monovalent cation exchange membrane under differing operational parameters. The ionic concentration variations, separation coefficients, lithium recovery ratio, permselectivity coefficient, and Li⁺ flux were analyzed to evaluate the effect of the initial Li⁺/Mg²⁺ mass concentration ratio, applied voltage, and initial volume ratio between the dilute and concentrated compartments on the separation performance of magnesium and lithium. The results showed that the increase in initial Li⁺/Mg²⁺ concentration ratio significantly increased the separation coefficient, lithium recovery ratio, and Li⁺ flux, demonstrating an improvement in the separation performance since the Li⁺ migration was accelerated when less Mg²⁺ competed with Li⁺. As the applied voltage increased from 10 V to 15 V, the separation coefficient increased, and the lithium recovery ratio and Li⁺ flux increased within 60 min; however, as the applied voltage increased to 20 V, the separation coefficient, the lithium recovery ratio, and the Li⁺ flux did not increase, which indicated that an increase in the applied voltage within the limits would contribute to the separation performance. The increase in the initial volume ratio between the dilute and concentrated compartments decreased the separation coefficient and lithium recovery ratio, indicating that the separation performance had declined. Full article