Search Results (1,173)

Background/Objectives: Although significant advances in duodenoscope reprocessing have been introduced since mid-2010s—including enhanced cleaning protocols, disposable distal endcaps, and the introduction of fully single-use duodenoscopes—residual contamination and infection risks remain unresolved. Moreover, repeated reprocessing may cause cumulative damage to the polymer surfaces, elevator mechanisms, and internal channels of the duodenoscopes, making them more susceptible to residual contamination. To minimize the duodenoscope polymer degradation caused by intensive use and reprocessing, new alternatives are urgently needed. In this context, calcium peroxide nanoparticles coated with sodium alginate (CaO₂–Alg NPs), synthesized by our group, were tested for the first time as a disinfectant capable of combating nosocomial pathogens while reducing device deterioration associated with repeated investigations and reprocessing. Methods: The disinfectant properties of the CaO₂–Alg NPs were evaluated under biomimetic conditions using reference bacterial strains commonly associated with nosocomial infections. In addition, the compatibility of the nanoparticles with the polymeric duodenoscope coatings was assessed after simulated intensive use. The external polymer coating was structurally and morphologically characterized by Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Atomic Force Microscopy (AFM), and Scanning Electron Microscopy (SEM). Results: The nanoparticles exhibited important antimicrobial activity against the reference bacterial strains Staphylococcus aureus, Escherichia coli, Enterococcus faecalis, and Klebsiella pneumoniae after only 20 min of incubation. Intensive exposure to the CaO₂–Alg NPs did not cause additional structural or morphological damage to the duodenoscope’s external polymers and did not alter their anti-adhesive properties. Conclusions: The CaO₂–Alg NPs appear to be a safe and effective disinfectant for the duodenoscope reprocessing, offering both antimicrobial efficacy and material compatibility. Full article

Selenium nanoparticles (Se NPs) have received increasing attention as a new alternative source to other forms of selenium in nutritional dietary supplements; however, the limited stability and pronounced tendency of selenium nanoparticles (Se NPs) to aggregate in aqueous environments have significantly constrained their practical applications. In this study, Poria cocos polysaccharide-modified Se NPs (PCP-Se NPs) were synthesized by the selenite/ascorbic acid chemical reduction method. PCP-Se NPs exhibited a uniformly dispersed spherical morphology with an average particle size of 66.64 ± 0.30 nm, and displayed an amorphous crystal structure. Compared to unmodified Se NPs, the PCP-Se NPs exhibited low Se release (8.83 ± 0.73%) after simulated gastrointestinal digestion, and they had excellent storage stability and salt ion stability. PCP-Se NPs exhibited potent antioxidant activity manifested by the effective scavenging of DDPH and ABTS radicals. PCP-Se NPs were efficiently internalized by RAW264.7 cells and released into the cytoplasm by a lysosomal escape mechanism, thereby effectively reducing intracellular inflammatory factor levels (the levels of MPO, NO, iNOS, TNF-α, IL-1β, and IL-10 in the PCP-Se NPs treatment group were 0.38 ± 0.013-fold, 0.26 ± 0.02-fold, 0.36 ± 0.02-fold, 0.57 ± 0.03-fold, 0.35 ± 0.02-fold, and 2.07 ± 0.16-fold that of the LPS group, respectively), alleviating oxidative stress (the levels of CAT, SOD, GSH, and MDA in the PCP-Se NP-treated group were 2.48 ± 0.02-fold, 1.91 ± 0.11-fold, 3.16 ± 0.28-fold, and 0.46 ± 0.03-fold that of the LPS group, respectively), and maintaining mitochondrial membrane potential stability. This study provides a basis and reference for improving the stability of Se NPs and developing novel selenium-enriched dietary supplements. Full article

With the recently acquired knowledge of the use of a multiphase mixture of precursors under electron beam irradiation (EBI), new possibilities were opened for this technique. In the present work, we obtained quantum dots, nanocrystals, nanoparticles, and grains of PbSe with a sintered appearance using a biphasic mixture of PbSe and PbSeO₃ under EBI. High-energy milling was used to obtain the biphasic mixture of precursors, which is composed of agglomerates with sizes ranging from ~400 to ~1700 nm, but nanoparticles were also present. The structural details of the biphasic mixture were studied using X-ray diffraction and the Rietveld method. The driving force of the EBI caused instantaneous physical and chemical changes due to the high internal energy of the biphasic mixture of precursors. The abrupt release of high internal energy, due to localized heating effects during EBI, gave way to the formation of multi-scale PbSe structures. Large particles with a sintered appearance formed near the electron beam impact point and in regions between ~800 nm and ~1400 nm, while well-defined faceted nanostructures were predominantly observed beyond ~1400 nm. The latter tended to be surrounded by {200} facets as the main growth direction. Furthermore, coalescence was anticipated to occur during EBI. It occurred simultaneously with the sublimation mechanism when the particle size was below the critical size of 10 nm. Multi-scale PbSe structures, obtained via EBI, are promising for developing thermoelectric devices due to their crystallinity and nanostructured features. Full article

Today, hydrogen is already widely regarded as up-and-coming source of energy. It is essential to meet energy needs while reducing environmental pollution, since it has a high energy capacity and does not emit carbon oxide when burned. However, for the widespread application of hydrogen energy, it is necessary to search new technical solutions for both its production and storage. A promising effective and cost-efficient method of hydrogen generation and storage can be the use of solid materials, including nanomaterials in which chemical or physical adsorption of hydrogen occurs. Focusing on the recommendations of the DOE, the search is underway for materials with high gravimetric capacity more than 6.5% wt% and in which sorption and release of hydrogen occurs at temperatures from −20 to +100 °C and normal pressure. This review aims to summarize research on hydrogen generation and storage using silicon nanostructures and silicon composites. Hydrogen generation has been observed in Si nanoparticles, porous Si, and Si nanowires. Regardless of their size and surface chemistry, the silicon nanocrystals interact with water/alcohol solutions, resulting in their complete oxidation, the hydrolysis of water, and the generation of hydrogen. In addition, porous Si nanostructures exhibit a large internal specific surface area covered by SiH_x bonds. A key advantage of porous Si nanostructures is their ability to release molecular hydrogen through the thermal decomposition of SiHx groups or in interaction with water/alkali. The review also covers simulations and theoretical modeling of H₂ generation and storage in silicon nanostructures. Using hydrogen with fuel cells could replace Li-ion batteries in drones and mobile gadgets as more efficient. Finally, some recent applications, including the potential use of Si-based agents as hydrogen sources to address issues associated with new approaches for antioxidative therapy. Hydrogen acts as a powerful antioxidant, specifically targeting harmful ROS such as hydroxyl radicals. Antioxidant therapy using hydrogen (often termed hydrogen medicine) has shown promise in alleviating the pathology of various diseases, including brain ischemia–reperfusion injury, Parkinson’s disease, and hepatitis. Full article

The paper explores the application of heat pipes in thermal management for efficient heat dissipation, particularly in electrical equipment with high heat loads. Heat pipes are devices that transfer heat with high efficiency through the phase transition of the working medium (e.g., water, alcohol, ammonia) between the evaporator and the condenser, while they have no moving parts and are distinguished by their simplicity of construction. Different types of heat pipes—gravity, capillary, and closed loop (thermosiphon loop)—are suitable according to specific applications and requirements for the working position, temperature range, and condensate return transport. An example of an effective application is the removal of heat from the internal winding of a static energy converter transformer, where the use of a gravity heat pipe has enabled effective cooling even through epoxy insulation and kept the winding temperature below 80 °C. Other applications include the cooling of mounting plates, power transistors, and airtight cooling of electrical enclosures with the ability to dissipate lost thermal power in the order of 102 to 103 W. A significant advantage of heat pipes is also the ability to dust-tightly seal equipment and prevent the build-up of dirt, thereby increasing the reliability of the electronics. In the field of environmental technology, systems have been designed to reduce the radiant power of fireplace inserts by up to 40%, or to divert their heat output of up to about 3 kW into hot water storage tanks, thus optimising the use of the heat produced and preventing overheating of the living space. The use of nanoparticles in the working substances (e.g., Al₂O₃ in water) makes it possible to intensify the boiling process and thus increase the heat transfer intensity by up to 30% compared to pure water. The results of the presented research confirm the versatility and high efficiency of the use of heat pipes for modern cooling requirements in electronics and environmental engineering. Full article

Background: Hepatocellular carcinoma is associated with high mortality and increasing incidence. Sorafenib, a cornerstone of therapy for advanced hepatocellular carcinoma, presents certain disadvantages, including low bioavailability and poor water solubility. This work describes a new strategy for sorafenib-targeted delivery aimed at improving treatment efficiency and reducing side effects. Methods: Magnetic nanoparticles coated with azelaic acid were modified with aptamer molecules that specifically recognize human liver cancer cell line HepG2, ensuring specificity for the tumor tissue. The nanoparticles were further loaded with sorafenib. The obtained drug delivery system was extensively characterized using UV-Vis spectrophotometry, transmission electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, and electrochemical impedance spectroscopy. Results: The drug delivery system demonstrated a higher release of sorafenib at acidic pH compared to pH 7.4. The cell internalization of the bare and aptamer-modified magnetic nanoparticles was assessed in HepG2 and human normal foreskin fibroblasts BJ cell lines, demonstrating that the aptamer significantly enhances internalization in tumor cells, while having no impact on healthy cells. Conclusions: The sorafenib-modified nanoparticles exhibited excellent cytocompatibility with BJ cells across all tested concentrations, while showing cytotoxicity towards HepG2 cells at higher concentrations, confirming the selectivity of the system. Full article

This study investigates the structural and magnetic properties of CoFe₂O₄ nanoparticles prepared by five different synthesis methods: coprecipitation, ultrasound-assisted coprecipitation, coprecipitation coupled with mechanochemical treatment, microemulsion and microwave-assisted hydrothermal synthesis. The produced powders were additionally functionalized with starch to improve biocompatibility and colloidal stability. The starch-coating procedure itself by sonication in starch solution, as well as its result, affects the structural and magnetic properties of functionalized nanoparticles. The resulting changes of properties in the process of ligand addition depend significantly on the starting nanoparticles, or rather, on the method of their synthesis. The structural, magnetic and spectroscopic properties of the resulting materials were systematically investigated using X-ray diffraction (XRD), Raman spectroscopy, Mössbauer spectroscopy and magnetic measurements. Taken together, XRD, Raman and Mössbauer spectroscopy show that starch deposition reduces structural disorder and internal stress, resulting in nanoparticles with a more uniform size distribution. These changes, in turn, affect all magnetic properties—magnetization, coercivity and magnetic anisotropy. Magnetic responses are preserved what is desirable for future biomedical applications. This work emphasizes the importance of surface modification for tailoring the properties of magnetic nanoparticles while maintaining their desired functionality. Full article

The fast and accurate calculation of the internal temperature rise in the oil-immersed transformer is the premise to realize the thermal health management and load energy evaluation of the in-service transformer. In view of the influence of nanofluids on the heat transfer process of transformer, a numerical simulation algorithm based on lattice Boltzmann method (LBM) and finite difference method (FDM) is proposed to study the heat and mass transfer process inside nano-modified oil-immersed transformer. Firstly, the D2Q9 lattice model is used to solve the fluid and thermal lattice Boltzmann equations inside the oil-immersed transformer at the mesoscopic scale, and the temperature field and velocity field are obtained by macroscopic transformation. Secondly, the electric field distribution inside the oil-immersed transformer is calculated by FDM. The viscous resistance in LBM analysis and the electric field force in FDM analysis, as well as the gravity and buoyancy of particles, are used to explore the motion characteristics of nanoparticles and metal particles. Finally, compared with the thermal ring method and the finite volume method (FVM), the relative error is less than 5%, which verifies the effectiveness of the numerical model and provides a method for studying the internal electrothermal convection of nano-modified oil-immersed transformers. Full article

Bismuth-based oxyfluorides (BiO_xF_3−2x) have recently emerged as promising photocatalysts due to their unique electronic structures and tunable physicochemical properties. This review provides a comprehensive overview of these materials, focusing on their crystal structures, band gap characteristics, and photocatalytic performance. Particular attention is given to BiOF, Bi₇O₅F₁₁, and β-BiO_xF_3−2x, highlighting the influence of fluorine’s high electronegativity and internal electric fields on charge separation and light absorption. The potential of Aurivillius-type oxyfluorides is also discussed. Structural modifications, such as the introduction of oxygen vacancies, morphology control, and metal/non-metal doping, are examined for their effects on photocatalytic efficiency. Furthermore, various synthesis techniques and heterojunction engineering strategies involving semiconductors, carbon-based materials, and metal nanoparticles are explored to improve light harvesting and reduce charge recombination. Applications in pollutant degradation and CO₂ photoconversion are reviewed, demonstrating the versatility of these materials. Despite their promise, the challenges associated with phase identification and composition control are also emphasized, underlining the need for rigorous structural characterization. Future directions for optimizing the photocatalytic activity of bismuth-based oxyfluorides are outlined, focusing on strategies to enhance their performance. Full article

In this study, we have established that unique composite particles (MLNCs) carried siRNA on a gold core and were covered with a lipid shell. MLNCs successfully delivered siRNa into cells in the presence of serum. We developed the photofixation method, allowing us to obtain MLNCs bearing a fixed protein corona. To understand the mechanisms of the influence that the protein corona has on the interaction of particles with cells, it is necessary to study the interaction of “naked” MLNCs with cells. This study aimed to examine the pathways of MLNC penetration into SC-1 fibroblasts used to confirm the efficacy of siRNA delivery. We studied fibroblasts in monolayer and spheroid form, and citrate AuNPs were used as a comparison particle. The same particles served as cores for MLNCs. The obtained results showed active penetration by clathrin-mediated endocytosis of “naked” MLNCs into SC-1 fibroblasts, regardless of the form of cultivation. AuNPs penetrated into monolayer fibroblasts by macropinocytosis and into spheroids by clathrin-mediated endocytosis. The penetration depth into the spheroids was about 40 μm for both types of particles (spheroid size was 350–400 μm). The particles migrated through the intercellular spaces, passing through intercellular contacts. Full article

Background/Objectives: Lyotropic liquid crystalline nanoparticles are promising drug delivery nanocarriers, exhibiting significant technological advantages, such as their extended internal morphology. In this study, cationic non-lamellar lyotropic–lipidic liquid crystalline nanoparticles were formulated by phytantriol lipid. Methods: The poly(2-(dimethylamino)ethyl methacrylate)-b-poly(lauryl methacrylate) block copolymer carrying tri-phenyl-phosphine cations (TPP-QPDMAEMA-b-PLMA), was employed as a stabilizer co-assisted by other polymeric guests. The exact qualitative and quantitative formulation of the systems was investigated. Their physicochemical profile was depicted from a variety of light scattering techniques, while their microenvironmental parameters were determined by fluorescence spectroscopy using adequate probe molecules. The effect of environmental conditions was monitored, confirming stimuli-responsiveness properties. Their morphology was illustrated by cryo-TEM, revealing expanded internal assemblies. Resveratrol was incorporated into the nanoparticles and the entrapment efficiency was calculated. Results: Their properties were found to be dependent on the formulation characteristics, such as the lipid used, as well as the architecture of the polymeric stabilizer, also being found to be stealth toward proteins, exhibiting stimuli responsiveness and high entrapment efficiency. Conclusions: The studied liquid crystalline nanoparticles, being stimuli-responsive, with high cationic potential, high loading capacity and showing intriguing 3D structures, are suitable for pharmaceutical applications. Full article

Objectives: This study planned to determine the biological effects associated with ZnFe₂O₄-NPs exposure using Drosophila melanogaster as an in vivo model. Methods: ZnFe₂O₄-NPs were hydrothermally synthesized, and the development of offspring flies were evaluated via dietary exposure to different doses of ZnFe₂O₄-NPs (0, 200, 400, 600 μg/mL). Rhythmic behaviors of parent male flies were monitored. Results: Internalization of ZnFe₂O₄-NPs through the intestinal barrier occurred. Oral intake of ZnFe₂O₄-NPs decreased the eclosed adult numbers and perturbed the insect developmental process. In male flies, significant upregulation of HSPs and Turandot family genes was detected, accompanied by ROS reduction and suppressed antioxidant defense responses, and exposure of ZnFe₂O₄-NPs disrupted sleep patterns of males, including a reduction in sleep duration and aggravation of sleep fragmentation. Suppressed activity levels were also found after ZnFe₂O₄-NPs exposure. Significant increased expressions of circadian genes (Clk and Cyc) were detected, alongside elevation of neurotransmitter levels and related gene expressions. Conclusions: Overall, ZnFe₂O₄-NPs can perturb development process via inducing heat shock and detoxification response, and disrupted rhythmic behaviors may be attributed to elevation of neurotransmitter levels and upregulated gene expressions of circadian genes. Our findings may offer valuable insights for evaluating ecological risks of metal-based nanoparticles and suggest potential applications in developing novel pest management strategies by utilizing insect behavioral and physiological responses to nanomaterials. Full article

This study presents an integrated experimental and computational investigation into the thermal and hydraulic performance of three oxide-based nanofluids: aluminum oxide (Al₂O₃), titanium dioxide (TiO₂), and copper oxide (CuO) for advanced engine cooling applications. A custom-built test rig was used to assess nanofluid behavior under varying flow rates, nanoparticle volume fractions, and temperature gradients, replicating realistic engine conditions. According to the results, at ideal concentrations, CuO nanofluids continuously demonstrate better heat transfer properties, outperforming TiO₂ by up to 15% and AlO₃ by 7%. However, performance plateaus beyond 1.5% volume fraction due to increased viscosity and pressure drop. A multilayer feedforward artificial neural network (ANN) model was developed to predict convective heat transfer coefficients and friction factors based on experimental inputs, achieving a mean absolute percentage error below 5% and a coefficient of determination (R²) exceeding 0.98. The ANN demonstrated robust generalization across varying operating conditions and nanoparticle types, confirming its utility for surrogate modeling and optimization. This work is distinguished by its dual focus on thermal efficiency and hydraulic stability, as well as its use of data-driven modeling validated by empirical results. The findings provide actionable insights for thermal management system design in internal combustion, hybrid, and electric vehicles, where efficient, compact, and reliable cooling solutions are increasingly vital. The study advances the practical application of nanofluids by offering a comparative, ANN-validated framework that bridges the gap between lab-scale performance and real-world automotive cooling demands. Full article

This study focuses on the numerical analysis of heat transfer in biological tissue. The proposed model is formulated using the Pennes equation for a two-dimensional cylindrical domain. The tissue undergoes laser irradiation, where internal heat sources are determined based on the Beer–Lambert law. Moreover, key parameters—such as the perfusion rate and effective scattering coefficient—are modeled as functions dependent on tissue damage. In addition, a fuzzy heat source associated with magnetic nanoparticles is also incorporated into the model to account for magnetothermal effects. A novel aspect of this work is the introduction of uncertainty in selected model parameters by representing them as triangular fuzzy numbers. Consequently, the entire Finite Pointset Method (FPM) framework is extended to operate with fuzzy-valued quantities, which—to the best of our knowledge—has not been previously applied in two-dimensional thermal modeling of biological tissues. The numerical computations are carried out using the fuzzy-adapted FPM approach. All calculations are performed due to the fuzzy arithmetic rules with the application of α-cuts. This fuzzy formulation inherently captures the variability of uncertain parameters, effectively replacing the need for a traditional sensitivity analysis. As a result, the need for multiple simulations over a wide range of input values is eliminated. The findings, discussed in the final Section, demonstrate that this extended FPM formulation is a viable and effective tool for analyzing heat transfer processes under uncertainty, with an evaluation of α-cut widths and the influence of the degree of fuzziness on the results also carried out. Full article

Lilium species produce some of the most commercially valuable ornamental flowers in the world, characterized by their attractiveness and high demand in cut flower markets. However, it is necessary to strengthen the competitiveness of this sector in the global market. Due to strong competition from international producers and an increasingly demanding market regarding quality, shelf life, and sustainability, alternatives are being sought to counteract the use of conventional agrochemicals. The use of nanoparticles has emerged as a promising strategy in ornamental horticulture due to their ability to enhance plant growth, improve stress tolerance, and stimulate physiological processes, ultimately contributing to higher quality and productivity. The hypothesis of this research is that the foliar application of selenium and titanium dioxide nanoparticles during the vegetative growth and flowering stages significantly enhances the growth, development, and flowering of Lilium plants when compared with untreated plants. Therefore, the physiological effects of SeNPs and TiO₂NPs applied via foliar application in two concentrations (SeNPsD1, SeNPsD2, TiNPsD1, and TiNPsD2) were evaluated against absolute control. The treatments were applied in two phenological stages (vegetative and reproductive development), and their effects on vegetative and reproductive variables in Lilium plants were evaluated from 120 to 270 days after sowing. The surface of seeds obtained from SeNPsD1-treated plants was further analyzed via scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDS). The results demonstrate that the application of SeNPs generated variable effects depending on the phenological stage. In the vegetative stage (46 DAS), SeNPsD2 increased the number of leaves by 118%, while SeNPsD1 increased the fresh weight of leaves by 110%. Regarding ovaries, the application of SeNPsD2 resulted in a 276% increase in fresh weight and a 230% increase in dry weight, while SeNPsD1 achieved an increase of 164% in fresh weight. Furthermore, at this stage, SeNPsD2 promoted a 223% increase in the number of bulbils, a 240% increase in fresh weight, and a 199% increase in dry weight. In the reproductive stage (69 DAS), SeNPsD1 increased the leaf fresh weight by 1% and yielded a 107% increase in the number of ovaries, in addition to 307% and 328% increases in their fresh and dry weights, respectively. In the same stage, SeNPsD2 increased the fresh ovary weight by 153%, compared with the control. Finally, capsule formation was observed only under the SeNPsD1 treatment. Meanwhile, TiO₂NPs had an effect on the number of buds and the number of open buds: the number of buds increased by 115% with TiNPsD1 (69 DAS) and the number of open buds increased by 104% (46 DAS) with TiNPsD1; in the reproductive stage, the number increased by 115% with TiNPsD1 compared with the control. In the seed capsules of plants treated with selenium nanoparticles (SeNPsD1), although no surface selenium was detected via EDS, elements that had possibly been physiologically redistributed were identified, including iron (Fe), silicon (Si), and aluminum (Al). These findings confirm the hypothesis of this research, demonstrating that the foliar application of SeNPs and TiO₂NPs to Lilium plants during the vegetative and reproductive stages significantly improves their vegetative growth, reproductive development, and floral quality under controlled conditions. This work presents the first comparative evidence regarding the effects of SeNPs and TiO₂NPs on the vegetative and reproductive characteristics of Lilium Sunny Oriental, providing unprecedented information for the use of nanotechnology in ornamental horticulture. The findings confirm the potential use of nanoparticles as agents to optimize the productivity and commercial quality of ornamental flowers in highly competitive markets. Full article