Search Results (1,475)

Dysphagia is a commonly encountered condition in clinical practice, with a rising incidence reported particularly in South Korea. It can be broadly classified into oropharyngeal dysphagia and esophageal dysphagia, and distinguishing between the two is crucial for establishing rehabilitation treatment strategies. Oropharyngeal dysphagia frequently occurs in central nervous system diseases such as stroke, dementia, and Parkinson’s disease and has a significant impact on prognosis. Additionally, because there is a high risk of life-threatening aspiration pneumonia in patients complaining of dysphagia, an accurate diagnosis must be made during the early stages of the condition. Patients with oropharyngeal dysphagia may report difficulty initiating swallowing and may experience coughing, choking, nasopharyngeal reflux, aspiration, and a sensation of leftover food in the pharynx during swallowing. Patients with esophageal dysphagia may report a sensation of food getting stuck in the esophagus for a few seconds after the initiation of swallowing. Esophageal dysphagia should be characterized by analyzing whether the foods causing dysphagia are solid, liquid, or both, as well as by the progression of symptoms, whether they are progressive or intermittent; their severity; and associated symptoms such as weight loss, heartburn, or regurgitation. Video fluoroscopic swallowing study (VFSS), fiberoptic endoscopic evaluation of swallowing (FEES), and esophagogastroduodenoscopy (EGD) are invaluable in determining the causes, severity, and treatment strategies for dysphagia. Since swallowing disorders are significant factors influencing the course and prognosis regardless of the type of disease, clinicians should adopt a systematic approach to such disorders. Full article

In order to study the curing process of branched polyazide glycidyl ether (BGAP) binder and its propellant slurry at 50 to 70 °C, the rheological properties of BGAP binder and its propellant slurry were studied by chemical rheology. The results show that the viscosity coefficient of the uncured BGAP decreases gradually when the temperature increases, and when the plasticization ratio is 1.1, the viscosity coefficient of BGAP decreases first and then remains unchanged. After adding the curing agent, the chemical rheology method can be used to calculate whether the BGAP curing system still conforms to the power-law equation in a short time. The kinetic equation of the curing reaction, expressed by apparent viscosity, is deduced from the double Arrhenius equation, which can be expressed by η(T,t) = 10.16 exp (−1.72/T) exp [17.27 t exp (−5.21/T)]. After using BGAP as the adhesive to make a propellant slurry with a liquid material component of 25%, the effect of the particle size of Al powder in the solid filler component on the curing process of the slurry was studied, and the 200 nm Al powder could not be made into a slurry under this formulation. The curing kinetics equations of the slurry with Al powder particle sizes of 5 μm, 15 μm, and 29 μm under this formula were obtained by measuring the viscosity of the slurry over time at 50–70 °C. The results showed that the smaller the Al powder particle size, the lower the viscous flow activation energy of the slurry and the higher the curing reaction activation energy. Full article

Semi-solid processes of aluminium alloys, characterised by the coexistence of solid and liquid phases, offer advantages in terms of mechanical properties and fatigue resistance, thanks to the more globular microstructure. Thermodynamic models can be used to analyse the solidification behaviour and to predict the solidification window, ΔT. The CALPHAD method enables the calculation of the phases formed during solidification and the optimisation of alloy composition to meet specific industrial requirements. This study aims to assess how thermodynamic properties in both liquid and solid phases affect the ΔT. Initially, the influence of thermodynamic properties of pure components and interaction parameters was analysed in simplified regular binary systems. To compare these findings with real industrial systems, Al-based alloys were examined. Using available databases, the ΔT was estimated via the CALPHAD method adding alloying elements commonly found in secondary Al-alloys. Finally, the same minority alloying elements were added to Al-Si 8 and 11 wt.% alloys, and the corresponding ΔT were calculated. Cr, Fe, Mg, Mn, and Ti increase the ΔT, while Cu, Ni, and Zn decrease it. The obtained results may serve as a valuable tool for interpreting phenomenological observations and understanding the role of minority elements in the semi-solid processing of secondary Al-Si casting alloys. Full article

Magnetic separation is an important method in the processing process, and its essence is the targeted dispersion of the mineral processing slurry pulp in the magnetic field space. The slurry is a complex multiphase fluid system with continuous phase carrying a large number of discrete phase particles, in which the magnetic particles agglomerate, migrate, and disperse under the dominance of magnetic force. In this process, there is nonlinear and unstable dynamic coupling between the continuous phase (liquid) and the discrete phase (solid particles) and between the discrete phases. In this paper, a dynamic cyclic multi-dipole magnetic moment algorithm with a higher calculation accuracy is innovatively proposed to calculate the magnetic interaction force between particles. Moreover, the P-E magnetization model suitable for a two-dimensional uniform magnetic field is further improved and optimized to make it applicable to a three-dimensional gradient magnetic field. Finally, based on the coupling of the Finite Element Method (FEM), Computational Fluid Dynamics (CFDs), and Discrete Element Method (DEM), a dynamic coupling model capable of accurately simulating the magnetic separation process is developed. This model can be used to study the separation behavior of particles under a multiphase flow and multi-force field and to explore the motion behavior of magnetic particles. Full article

Sediment-laden water significantly exacerbates the cavitation damage in hydraulic machinery compared to clear water, underscoring the importance of investigating the effects of sediment on cavitation. This study examines cavitation in sediment-laden water using a Venturi flow channel and a high-speed camera system. Natural river sand samples with a median diameter of 0.05, 0.07, and 0.09 mm are selected, and sediment-laden water with a concentration of 10, 30, and 50 g/L is prepared. The results indicate that increasing the sediment concentration or reducing the sediment size intensifies cavitation, and the influence of the sediment concentration is significantly greater than that of the sediment size. Meanwhile, the numerical simulation is conducted based on a gas–liquid–solid phase mixing model. The findings indicate that a higher sediment concentration corresponds to a greater shearing effect near the wall, which raises the drag on the attached sheet-like cavitation clouds and enhances the re-entrant jet which can intensify the shedding of cavitation clouds. Furthermore, sediment particles contribute to more vortices. Therefore, for hydraulic machinery operating in sediment-laden water of high concentration, the relative velocity should be reduced to mitigate the shearing effect, thereby weakening the synergy of cavitation and sediment erosion at the turbine runner. Full article

The combination of a liquid piston gas compressor and a solid metal insert can achieve a near-isothermal compression process, which can greatly contribute to improving the system efficiency of a compressed-air energy storage system. To examine the effectiveness of the insert at various pressure levels, compressions were performed in a liquid piston compressor with and without copper wire mesh inserts at three different pressures of 1, 2, and 3 bars. The use of inserts increased isothermal compression efficiencies by 8–10% from the baseline isothermal efficiencies about 83–87%, while the compromised air volume due to the inserts was minor. In addition to the solid insert-based technique analysis, a comparative study with other proven liquid-based heat transfer enhancement techniques, spray injection and aqueous foam, was performed. Not only was a quantitative analysis made comparing the isothermal efficiency values but the pros and cons of each technique’s distinctive working mechanisms were also compared. Full article

Hyperhydricity is a significant challenge in the tissue culture of blueberry plantlets, affecting their propagation, survival and quality, which results in economic losses for industrial blueberry micropropagation. The in vitro liquid propagation of two half-highbush blueberry hybrids, HB₁ and HB₂, showed that a Growtek stationary bioreactor culture system containing a liquid medium exhibited a higher hyperhydricity percentage than a Sigma glass culture system with a semi-solid medium. The percentage of hyperhydricity (75.21 ± 1.89%) and water content (72%) of HB₂ was more than that of HB₁. A scanning electron microscopy study revealed that hyperhydric plantlets from both genotypes developed slowly, had closed stomata, and displayed enlarged intercellular spaces between the palisade and spongy parenchyma layers. Disrupted vascular bundles, underdeveloped sieve elements and a weak connection between phloem and xylem tissue were also observed in hyperhydric plantlets. An analysis of mesophyll and stem tissues highlighted a compressed adaxial epidermis, which led to compact palisade parenchyma, with irregularly shaped mesophyll cells. Hyperhydric plants showed strong nuclear magnetic resonance (NMR) signals in the aliphatic, aromatic, and sugar regions, specifically at peaks of 2.0, 2.5, 4.0, 4.5, 6.0, and 6.7 ppm. These signals were attributed to the presence of catechin (C₁₅H₁₄O₆), a flavonoid compound, suggesting its significant role or accumulation in these plants under hyperhydric conditions. Despite the negative effects of hyperhydricity on commercial propagation, hyperhydric plants were found to contain higher levels of valuable untargeted metabolites, such as β-P-arbutin, chlorogenic acid, quercetin-3-O-glucoside, epicatechin, 2-O-caffeoyl arbutin, various fatty acids, β-glucose, linolenic acid, and acetyl than both in vitro and ex vitro conditions. The enrichment of bioactive compounds in blueberry enhances its antioxidant properties, nutritional profile, and potential health benefits, making them significant for plant defense mechanisms and stress adaptation. Full article

The efficient liquefaction of cellulose is a critical technological pathway for the energy utilization of biomass. This study constructed a plasma electrolytic liquefaction experimental system based on the principle of liquid phase surface arc discharge, systematically investigating the effects of operational parameters, including working voltage, catalyst dosage, solid–liquid ratio, and micro-arc polarity, on the liquefaction characteristics of microcrystalline cellulose. Experimental results demonstrated that under optimized conditions—anode micro-arc configuration, working voltage of 750 V, catalyst dosage of 1.44 g, and solid–liquid ratio of 6:38—the cellulose conversion rate reached 79.2%, with a liquefied product mass of 4.75 g. Mechanistic analysis revealed that high-energy electrons and hydrogen ions generated by plasma discharge synergistically act on the cleavage of cellulose molecular chains. Under the combined effects of the catalyst and plasma, cellulose molecules are depolymerized into small molecular compounds. Compared with traditional liquefaction processes, this technology exhibits significant advantages in reaction rate and energy efficiency, providing a novel technical route for the efficient conversion of biomass resources. Full article

Heterocyclic aromatic amines (HAAs), known for their mutagenic and carcinogenic potential, are formed during the heating of protein-rich food items. Detecting HAAs swiftly and accurately poses challenges due to complex food matrices and low HAA concentrations. In this study, a simple and efficient magnetic solid-phase extraction (MSPE) strategy was developed for the simultaneous isolation and enrichment of three HAAs such as 2-amino-3,4,8-trimethylimidazo [4,5-f]quinoxaline (4,8-DiMeIQx), 2-amino-3,8-dimethylimidazo [4,5-f]quinoxaline (MeIQx), and 2-amino-3-methylimidazo [4,5-f]quinoline (IQ) in processed meats, employing the magnetic covalent organic framework Fe₃O₄@MOF-545-AMSA as an adsorbent. It was synthesized via a solvothermal method, with Fe₃O₄ as the magnetic core. Its building blocks are as follows: zirconium (Zr) as the coordination metal ion, tetrakis(4-carboxyphenyl)porphyrin and benzoic acid as organic ligands, and aminomethanesulfonic acid (AMSA). This composite captures targeted HAAs efficiently by exploiting the unique porous MOF-545-AMSA structure, specific metal–ligand coordination, and AMSA’s amino and sulfonic acid groups. The quantification of HAAs was achieved through the combination of Ultra-Performance Liquid Chromatography–Tandem Mass Spectrometry (UPLC-MS/MS) and MSPE, demonstrating satisfactory linearity (R² ≥ 0.9917), high recovery rates (83.7–111.0%), and low detection limits (0.1–1.0 μg/kg). Moreover, an automated high-throughput detection system was developed using MSPE to assess the presence of HAAs in meat products. Full article

Janus nanorods are a special class of nanorods composed of two distinct surface regions, one hydrophilic and one hydrophobic. This amphiphilic characteristic makes them promising candidates for stabilizing water–oil interfaces. Oily wastewater (OWW) contamination, resulting from industrial activities such as petroleum extraction and refining and vegetable oil processing, poses significant risks to ecosystems, water resources, and public health. Traditional surfactants used in enhanced oil recovery (EOR) and wastewater treatment often introduce secondary pollution due to their persistence and toxicity. In this work, we investigate the interfacial behavior of Janus NRs under two different conditions: a thin oil film surrounded by water and a nanoconfined system with purely repulsive walls. Using dissipative particle dynamics (DPD) simulations, we analyze how nanorod length and confinement influence interfacial tension and self-assembly. In bulk systems, shorter NRs (dimers and quadrimers) effectively reduce interfacial tension by adsorbing at the oil–water interface, while longer NRs (hexamers) exhibit bulk aggregation, limiting their surfactant efficiency. In contrast, under nanoconfinement, all NR sizes increase interfacial tension due to steric constraints, with longer NRs preferentially adsorbing onto the solid–liquid interface. These results pave the way for the rational design of nanostructured materials for applications in enhanced oil recovery, wastewater treatment, and membrane filtration. Full article

In recent years, various green solvents have played more and more important roles in catalysis and biomass studies. In this work, three imidazolium anion-based alkaline ionic liquids (ILs, including [BMIM]Im, [Ch]Im, and [N₄₂₂₂]Im) were selected to catalyze the oxidative degradation of alkaline lignin by a microwave-assisted hydrogen peroxide–alkaline ionic liquid system for the first time, which aimed to promote the depolymerization and high-value conversion of lignin and increase the number of alcohol hydroxyl groups and the reactivity of lignin. The changes in the number of the alcohol hydroxyl groups of lignin before and after degradation were taken as the primary indices. As the main conditions, the influence of the microwave exposure time, microwave power, ionic liquid concentration, and hydrogen peroxide concentration on the degradation efficacy was subsequently examined for the ionic liquid that exhibited the most effective degradation performance. In addition, the extracted lignin degradation reaction solution was analyzed in combination with gas chromatography–mass spectrometry (GC–MS), and the degraded lignin solids were characterized by scanning electron microscopy (SEM), ultraviolet and visible (UV–Vis) spectroscopy, Fourier-transform infrared spectroscopy (FT–IR), and thermogravimetric and derivative thermogravimetric (TG–DTG) methods, which determined the composition of the degradation products, the degradation mechanism, and the intuitive structural changes in the lignin, thereby providing insights into the extent of lignin degradation with green solvents. Full article

Sustainable hydrocarbons are one of the main methods of decreasing the use of fossil fuels and derivatives, contributing to the mitigation of environmental impacts and greenhouse gas emissions. Circular economic concepts focus on reusing waste by converting it into new products, which are then input again into industrial production lines, thus decreasing the necessity of fossils. Polypropylene-based plastic waste can be depolymerized into smaller chemical chains, producing a liquid phase rich in hydrocarbons. In the same way, triacylglycerol-based waste biomasses can also be converted into renewable hydrocarbons. Our research studied the co-processing of polypropylene (PP) and cottonseed oil dreg (BASOs) waste from the biodiesel industry using a micropyrolysis system at 550 °C, previously validated to predict the scale-up of the process. PP showed the production of alkanes and alkenes, while BASOs also produced carboxylic acids in addition to the PP products. The main impacts were observed in the conversion yields, reaching the highest values of pyrolytic liquid (64%), gas (14%), and solid product (13%) compared to the co-processing mixture of BASO:PP (1:2). Also, in this mixture, the production of carboxylic acids decreased to the lowest value (~10%), improving the conversion to sustainable hydrocarbons. Full article

Background/Objectives: Non-small cell lung cancer (NSCLC) constitutes over 84% of all lung cancer cases and is a leading cause of cancer-related mortality globally. Alectinib, a second-generation anaplastic lymphoma kinase (ALK) inhibitor, is effective in ALK-positive NSCLC; however, its clinical potential is hampered by poor aqueous solubility and limited oral bioavailability. This study aimed to develop Alectinib-loaded chitosan–alginate nanoparticles (ACANPs) to enhance its solubility, oral bioavailability, and therapeutic efficacy. Methods: ACANPs were synthesized using a novel combined solid/oil/water (s/o/w) emulsification technique with ionotropic gelation. Characterization was performed using Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), dynamic light scattering (DLS), and zeta potential measurements. A validated high-performance liquid chromatography (HPLC) method quantified the Alectinib. In vitro drug release studies compared free Alectinib with ACANPs. Cytotoxicity against NSCLC cell lines (A549 and H460) was assessed using MTT assays. Pharmacokinetic parameters were evaluated in rats using LC–MS/MS. Results: ACANPs showed a high encapsulation efficiency (~97%), an average particle size of 161 nm, and a positive zeta potential of +21 mV. In vitro release studies revealed a threefold increase in drug release from ACANPs over 48 h compared to free Alectinib. Cytotoxicity assays demonstrated significantly reduced IC₅₀ values for ACANPs. Pharmacokinetic analyses showed an enhanced maximum plasma concentration (C_max) and area under the curve (AUC), indicating a 78% increase in oral bioavailability. Conclusions: ACANPs substantially improved the solubility, cytotoxic efficacy, and oral bioavailability of Alectinib, suggesting their potential as a promising nanocarrier system for enhancing NSCLC treatment outcomes. Full article

Minimizing the risk of secondary caries in dentistry is achieved by using adhesive systems that provide a strong bond between the natural hard tissue and the restorative material. Evaluating the effectiveness of these systems requires studying both their interaction with dentin and enamel and their behavior in environments with varying acidity. In this work, the interaction of a reactive monomer, 4-methacryloxyethyl trimellitic anhydride (4-META), used in adhesive systems with both dentin-like hydroxyapatite (HA) and hydroxyapatite ceramics, was investigated. Kinetic studies showed that under experimental conditions, 4-META was hydrolyzed and amorphized. Dentin-like HA possessed greater adsorption capacity to 4-META than ceramic HA. Immersion of HA into a solution of 4-META led to formation of an acidic calcium phosphate phase over time in both systems. Studies on the solubility of the synthetic nanosized hydroxyapatite and its derivative with 4-META in 0.1 mol/L lactic acid, also containing CaCl₂, Na₂HPO₄, and NaF (pH 4.5), and in distilled water (pH 6.3) indicated the occurrence of dissolution, complexation, and crystallization processes, causing changes in the liquid and solid phases. The total Ca²⁺ concentration upon dissolution of hybrid HA-4-META in a lactic acid solution was three times lower than the total Ca²⁺ concentration upon dissolution of pure HA. This suggested that 4-META-treated dentin-like surfaces demonstrate greater resistance to dissolution in acidic environments compared to untreated surfaces, highlighting the potential for these hybrids in dental applications. Full article

This study investigates the flow dynamics and damage characteristics of liquid level control valves in direct coal liquefaction processes. The primary failure mechanisms are identified as eccentric jet-induced unilateral wall damage, cavitation erosion, and solid particle erosive wear. A numerical simulation framework was developed to analyze the effects of varying spool angles (72°, 90°, 98°, 105°, and 120°) on flow stability, cavitation dynamics, and erosion patterns. The key findings include the following: A spool angle of 90° achieves the most uniform pressure distribution and minimizes eccentric jet phenomena. Spool geometry modifications exhibit a negligible influence on cavitation characteristics. Reduced wear rates are observed at smaller spool angles (72° and 90°), with the lowest particle-induced erosion occurring at 90°. There is a certain correlation between the particle residence time and the wear of the valve core wall, which is illustrated in the shorter residence times that are correlated with accelerated material degradation. The optimal spool angle of 90° simultaneously mitigates eccentric jet effects, cavitation, and erosive wear. This research provides novel insights for predictive failure analysis and the structural optimization of control valves in high-pressure multi-phase flow systems. Full article