Search Results (21,021)

High-pressure water injection (HPWI) can rapidly replenish the formation energy of low-permeability reservoirs, but it may trigger multi-scale fractures, leading to premature water breakthrough between injection and production wells. To identify the main causes and regulate the mainstream line (i.e., the preferential flow path with the highest streamline density/flow rate), a two-zone and five-point numerical model was developed. This model couples the static damage zone (dominated by micro-fractures) and the fracture development zone (dominated by macro-fractures). Through sensitivity analysis, the ways in which micro-fracture damage and macro-fracture geometry control the evolution of seepage patterns and the risk of water breakthrough were quantified. The results show that in the representative scenarios of this paper, micro-fracture damage is mainly associated with an increased risk of water breakthrough by forming equivalent weakening zones and enhancing the directional extension trend of main fractures. The scale of macro-fractures has the strongest correlation with the water breakthrough response. When the fracture scale increases to a certain proportion close to the well spacing, the seepage mode changes from “fracture + matrix cooperation” to “main-fracture-dominated short-circuit channel”. Based on this, a design and verification of a combined control scheme of “chemical profile control + cyclic water injection” was proposed and carried out in well groups with high water cut and strong channeling. Simulations show that this combination helps to weaken the flow conductivity of preferential channels and improve the uniformity of the flow field. This paper can provide technical support for the prevention, control, and early warning of water breakthrough and the regulation of main flow lines in the high-pressure water injection development of similar low-permeability reservoirs. Full article

Globally, freshwater scarcity is driving the urgent demand for advanced and new desalination technologies to overcome the shortage of clean water. Reverse osmosis (RO) membranes dominate seawater and brackish water treatment but are limited by the permeability–selectivity trade-off, fouling, and structural instability. To overcome these challenges, we employed a phase inversion process to fabricate polysulfone (PSF) supports embedded with a graphene oxide–poly(amidoamine) (GO-PAMAM) nanocomposite at three concentrations (0.03, 0.06, and 0.10 wt%), alongside a pristine control membrane with no GO-PAMAM. Systematic variation in GO-PAMAM loading revealed that a 0.06 wt% nanoparticle helps in producing a more uniform polyamide layer that achieves a high NaCl rejection (95.88%) and higher water flux (42.6 L m⁻² h⁻¹). The performance was evaluated at an operating pressure of 20 bar with a feed flow rate of 4 L min⁻¹. The optimized membrane also demonstrated an improved fouling resistance, retaining 93% of its initial flux after fouling. This scalable approach highlights substrate-level modification as an effective strategy for next-generation RO membranes, advancing sustainable and energy-efficient desalination to meet escalating global water demands. Full article

Lipid-based delivery systems (LDS), including lipid nanoparticles (LNPs) and liposomes, have become indispensable tools in modern biomedicine owing to their biocompatibility, capacity to encapsulate diverse therapeutic agents, and potential for targeted delivery. Despite their clinical success, conventional batch-based manufacturing methods are hindered by variability, limited scalability, and complex processing steps, slowing their broader translation. Microfluidic technologies offer a transformative solution by enabling precise fluid handling, rapid mixing, and reproducible production of LDS with tunable physicochemical attributes such as particle size, lamellarity, and drug-loading efficiency. This review highlights advances in microfluidic design strategies, including hydrodynamic flow focusing, staggered herringbone mixers, and toroidal micromixers, and evaluates how critical parameters such as flow rate, solvent composition, and lipid concentration influence LDS performance. Furthermore, we discuss the application of microfluidics in drug delivery, nucleic acid therapeutics, and vaccine platforms, underscoring its role in improving scalability, quality control, and clinical translation. Finally, we examine current challenges, including throughput limitations and solvent handling, while outlining future directions for integrating emerging materials and additive manufacturing to optimize LDS fabrication. Collectively, microfluidic platforms provide a promising pathway for next-generation lipid nanomedicines with enhanced precision, reproducibility, and therapeutic efficacy. Full article

Large-scale backward-curved centrifugal fans without volutes are extensively employed in enclosed air-cooled electric motors owing to their exceptional heat dissipation performance. This category of fans features substantial blade dimensions and a multitude of optimization parameters, which introduce challenges such as diminished predictive accuracy in high-dimensional optimization spaces. To address these issues, this paper proposes a blade optimization design methodology based on a GA-Kriging surrogate model. Sobol’s global sensitivity analysis is first employed to reduce model dimensionality. Subsequently, a high-fidelity aerodynamic performance prediction model is constructed through the integration of a Genetic Algorithm (GA) and a Kriging model. A constrained optimization is then conducted with volumetric flow rate and static pressure as the design objectives, and shaft power along with geometric point coordinates as the constraints. Experimental test results demonstrate that the fan optimized via the surrogate model, while maintaining low prediction error, achieves a 14% increase in volumetric flow rate and a 20% improvement in static pressure. This outcome indicates a significant enhancement in the overall aerodynamic performance. Full article

Background: Myricetin (MYR) is a natural flavonol with antioxidant, neuroprotective, anti-inflammatory, antidiabetic, and cardioprotective activities. Still, its pharmaceutical use is limited by very low aqueous solubility (~16.6 µg/mL) and poor oral bioavailability (<10%). This study aimed to enhance the solubility and potentially improve the bioavailability of MYR by developing an amorphous nanofibrous delivery system. Methods: Electrospinning was applied to fabricate MYR-loaded nanofibers using polyvinylpyrrolidone K30 (PVP30), and the influence of key processing parameters on MYR solubility was evaluated. Nanofibers produced under selected electrospinning conditions were characterized in terms of morphology, encapsulation efficiency, and physicochemical properties. Results: X-ray powder diffraction confirmed complete amorphization of MYR within the BB5 fiber structure (distance: 12 cm, voltage: 25 kV, flow rate: 1.5 mL/h). FTIR analysis indicated hydrogen-bonding interactions between MYR hydroxyl groups and PVP30 carbonyl groups, contributing to stabilization of the amorphous form. SEM images revealed homogeneous, defect-free fibers with diameters below 400 nm, although localized MYR agglomerates were observed. Solubility and release studies demonstrated a characteristic spring-and-parachute effect, enabling rapid MYR release and maintenance of a supersaturated state. Enhanced solubility resulted in significantly improved antioxidant activity in DPPH and CUPRAC assays compared with crystalline MYR. Conclusions: Electrospun PVP30 nanofibers represent a promising platform for improving the solubility, dissolution behavior, and functional activity of poorly soluble bioactive compounds such as myricetin, supporting their potential application in pharmaceutical formulations. Full article

Previous numerical simulations of polymer injectors often rely on fixed-viscosity models, which fail to accurately capture the severe shear degradation of non-Newtonian fluids under high-shear throttling conditions. To address this limitation and enhance polymer flooding efficiency, this study proposes an improved Carreau–Yasuda viscosity constitutive model to precisely simulate the flow behavior of polyacrylamide (HPAM) solutions. A comprehensive computational fluid dynamics (CFD) model was developed and validated, showing a viscosity prediction error of less than 8.6% across a wide shear rate range (0.1–10,000 s⁻¹). Based on this dynamic rheological model, the internal flow channel of the injector was optimized, resulting in a novel spindle-type throttling unit. Simulation and field validation results demonstrate that the optimized structure achieves a significant pressure drop of 6.03 MPa at an injection flow rate of 96 m³/d—representing a 65% improvement over traditional designs—while successfully maintaining a viscosity retention rate above 85%. This research overcomes the traditional design conflict between high pressure reduction and viscosity preservation, providing an accurate numerical framework and practical guidance for engineering high-flow, robust-throttling polymer injectors. Full article

In this work, compatibilized poly(lactic acid)/poly(butylene adipate-co-terephthalate) (PLA/PBAT) blends were developed and characterized, to be potentially utilized as biodegradable self-healing matrices for composite laminates. Blends containing 10, 20 and 30%wt of PBAT and 0.5 phr of an epoxy-based compatibilizer were prepared by melt compounding and hot pressing. Rheological measurements showed that moduli and complex viscosity generally increased with PBAT content, while maintaining viscosity levels suitable for conventional melt-processing operations. FT-IR and FESEM analyses confirmed the formation of an immiscible but well-compatibilized morphology, characterized by a homogeneous dispersion of PBAT domains within the PLA phase. Mechanical tests revealed a decrease in tensile modulus (up to 44%), strength (up to 45%) and fracture toughness (up to 40%) with a PBAT content up to 30%wt. Self-healing was evaluated by measuring the fracture toughness (K_IC) recovery after thermal treatment at 140 °C. After healing, the blend containing 20%wt of PBAT exhibited a self-healing efficiency of 64% under impact conditions, which was attributed to the smoother fracture surface generated at an elevated strain rate that facilitated a more effective flow of the molten PBAT phase across the crack interface during healing. The formulation containing 20%wt of PBAT featured the best balance between mechanical performance and self-healing efficiency. Full article

Although many studies have focused on the initial adhesion of bacteria, there have been few that looked at responses to changing environmental conditions. To more closely examine the viscoelastic nature of initial adhesion, surface-associated bacteria were quantified and monitored for their Brownian motion vibrations. This study used a flow chamber to observe the surface association of Enterobacter cloacae BS 1037, Staphylococcus aureus ATCC 12600, Klebsiella pneumoniae–1, Acinetobacter baumannii–1, Pseudomonas aeruginosa PA O1, and Enterococcus faecalis 1396 to glass under dynamic shear rates of 7–15–30 s⁻¹, 15–30–60 s⁻¹, and 30–15–7 s⁻¹. Comparing increasing and decreasing shear rates, information about retention and recovery became apparent. Coccoid bacteria primarily reacted to directional changes in shear rates with changes in either surface-associated bacterial densities or surface-associated strength independently. A. baumannii and E. faecalis did not change their associated strength, whereas S. aureus did not change its associated density. Bacillus bacteria demonstrated differences in both associations with directional changes in shear rates. We demonstrate that retention and recovery are different methods of adaptation to environmental conditions utilised by different bacterial species. These adaptations may form the basis of upregulation and downregulation responses used for survival. Full article

This study investigates how outlet pressure influences the fire suppression performance of a compressed air foam system (CAFS), with the aim of supporting system optimization and engineering applications. An experimental apparatus for foam performance testing is used to measure changes in foam flow rate, expansion, initial velocity, initial momentum, and drainage time at different outlet pressures. On the basis of relevant theoretical models, the factors causing discrepancies between model predictions and experimental results are examined, and the models are then refined. How the outlet pressure of CAFS affects foam performance is thereby clarified. The results show that foam flow rate increases as outlet pressure increases. At higher pressures, shear-thinning and intensified gas–liquid mixing affect the foam. As a result, the growth of flow rate in the range of 0.01–0.03 MPa is significantly higher than that in the range of 0.06–0.10 MPa. Both initial velocity and initial momentum increase significantly with increasing pressure, whereas the expansion decreases. Within the outlet pressure range of 0.01–0.10 MPa, the initial velocity increases from 1.23 m/s to 6.65 m/s, the initial momentum rises from 4.6 kg·m/s to 34.1 kg·m/s, and the expansion decreases from 9.2 to 5.4, indicating reduced foam stability. Drainage time and drained mass vary non-monotonically with outlet pressure. The longest drainage time and the smallest drained mass occur at 0.06 MPa. Fire suppression performance improves as outlet pressure increases. A higher outlet pressure enables the foam solution to penetrate the flame zone more effectively and to cover the surface of the burning material. In addition, changes in foam properties enhance the thermal insulation and smothering effects of the foam layer, as well as its heat absorption and cooling capacity. These effects together improve the efficiency of fire source cooling. Full article

Objectives: Diuretics are frequently used in bronchopulmonary dysplasia (BPD), yet evidence describing their short-term physiological effects remains limited. This study aimed to describe early changes in respiratory support parameters and safety outcomes following combined oral spironolactone and hydrochlorothiazide (SP/HCTZ) therapy in preterm infants with BPD. Methods: A retrospective, single-center before–after observational study was conducted. Preterm infants diagnosed with BPD who initiated SP/HCTZ therapy were included. Respiratory parameters (FiO₂, PEEP, and flow rate) and serum electrolytes were compared between Day 1 (initiation) and Day 3 of treatment. A predefined clinical response was defined as either a ≥10% reduction in FiO₂ or a step-down in respiratory support modality. Results: Fifty-six infants (mean gestational age 27.7 ± 2.3 weeks) were analyzed. After 72 h of SP/HCTZ therapy, mean FiO₂ decreased from 26.2 ± 6.3% to 22.4 ± 3.4% (p < 0.001). Significant reductions were also observed in PEEP and cannula flow rates (p = 0.004 and p = 0.003, respectively). Overall, 39 infants (69.6%) met the predefined clinical response criteria. The prevalence of hyponatremia (Na < 133 mmol/L) increased from 7.1% at baseline to 25.0% on Day 3 (p = 0.039). Conclusions: Initiation of SP/HCTZ was temporally associated with short-term reductions in respiratory support parameters; however, these findings should be interpreted as associations rather than treatment effects. Given the increased frequency of hyponatremia by Day 3, close electrolyte monitoring appears warranted during the early phase of therapy. Full article

The corrosion behavior of pipeline steels in marine environments is strongly affected by hydrodynamic conditions and microbial activity, yet their coupled influence remains insufficiently understood. In this study, the corrosion behavior of X70 pipeline steel was systematically investigated in flowing artificial seawater over a velocity range of 0–1.5 m/s, under both sterile conditions and in the presence of Pseudomonas aeruginosa. Corrosion weight loss measurements, electrochemical techniques, and surface characterization were employed to evaluate flow-dependent corrosion evolution. The results show that flow velocity plays a dominant role in regulating corrosion behavior. Under sterile conditions, increasing flow velocity enhances mass transfer and surface renewal, leading to progressively increased corrosion severity. In the presence of P. aeruginosa, corrosion behavior exhibits a non-monotonic dependence on flow velocity. Lower flow velocities are associated with reduced corrosion rates and relatively uniform surface degradation, whereas moderate flow velocities promote localized corrosion and increased pitting severity. At higher flow velocities, strong hydrodynamic effects suppress the retention of corrosion products and microbe-associated surface layers, resulting in corrosion behavior primarily controlled by fluid flow. Overall, the results indicate that microbial presence modifies the flow–corrosion relationship of X70 steel by altering interfacial conditions under low-to-moderate flow regimes. Full article

In recent years, screen pipe scaling and blockage have occurred in dozens of wells in the Fuling Shale Gas Field, seriously affecting the normal production of gas wells. Investigations show that similar problems exist in the Weirong Shale Gas Field of Sinopec Southwest Branch, and the Changning and Weiyuan Shale Gas Fields of PetroChina. Although well production has been restored through pipe inspection operations, key issues specific to shale gas wells remain unresolved, including the scaling mechanism under gas–liquid two-phase flow regimes unique to horizontal shale gas wells, the scale deposition law at screen pipes caused by complex flow direction changes, and the targeted prevention technologies for high-hardness BaSO₄ scale in high-salinity produced water. By jointly conducting research on the scaling mechanism and prevention technology of shale gas wellbores with Southwest Petroleum University, the Fuling Shale Gas Field has identified the reasons why the amount of BaSO₄ scaling increases with the decrease in pressure and temperature, while it increases with the increase in gas–water ratio. It has clarified the influencing characteristics of factors such as pressure, temperature, gas–water ratio and pipe wall roughness. The amount of scaling on the tubing wall of shale gas wells in this area is very small, and blockage mainly occurs at and near the screen pipe. Due to the complex flow direction change in gas and water in the screen pipe, the precipitated tiny scale particles separate, settle and accumulate, forming variable-diameter steps that continue to grow. Two agents have been developed: the LPPAS scale inhibitor and the barium-strontium-sulfate-chelating plug-removing agent, with a scale inhibition rate as high as over 90% and a scale dissolution rate over 70%, respectively, laying a foundation for the efficient and stable production of shale gas wells. Full article

Background/Objectives: This study aimed to evaluate macular choroidal blood flow dynamics and structural alterations in children with hyperopic anisometropic amblyopia and compare these findings with those of the fellow eyes. Methods: This retrospective observational study included 36 eyes from 18 children (mean age: 4.9 years) with unilateral hyperopic anisometropic amblyopia. Central choroidal thickness (CCT) was measured using enhanced depth imaging optical coherence tomography. Macular choroidal hemodynamics were assessed using laser speckle flowgraphy. Mean blur rate (MBR) was used as an index of blood flow, whereas beat strength (BS) was used as a measure of pulsatility. Ocular perfusion pressure (OPP) was also calculated. All parameters were compared between amblyopic and fellow eyes. Results: Amblyopic eyes demonstrated significantly greater CCT compared with fellow eyes (407.6 ± 84.9 µm vs. 326.4 ± 79.1 µm). Conversely, macular MBR was significantly lower in amblyopic eyes (9.28 ± 3.60 AU vs. 10.94 ± 4.68 AU), as was BS (5.73 ± 3.07 AU vs. 7.28 ± 3.59 AU). No significant differences were observed in central retinal thickness or OPP between amblyopic and fellow eyes. In amblyopic eyes, CCT was not significantly correlated with macular MBR or BS. Conclusions: Amblyopic eyes exhibited significant central choroidal thickening accompanied by reduced macular blood flow and pulsatility. These findings suggest that localized macular hemodynamic dysregulation may contribute to the pathophysiology of hyperopic anisometropic amblyopia. Full article

Background: Abnormal activation of the NRF2-cGAS-STING-NF-κB pathway can trigger an inflammatory cascade in rheumatoid arthritis (RA). Curcumin (CUR), a polyphenolic compound extracted from turmeric, possesses anti-inflammatory activity, but whether it can modulate this pathway to ameliorate RA remains unclear. This study aims to elucidate whether CUR inhibits the inflammatory response in synovial fibroblasts (MH7A) by suppressing the NRF2-cGAS-STING-NF-κB signaling cascade. Methods: An RA inflammatory model was constructed by stimulating MH7A cells with 20 ng/mL tumor necrosis factor (TNF). Groups included a control group, a model group, a methotrexate positive control group [MTX(methotrexate), 10 μmol/L], and curcumin treatment groups at varying concentrations (10–100 μmol/L). Cell viability was assessed using the CCK-8(Cell Counting Kit-8) assay. Cell migration and invasion capabilities were evaluated via scratch wound healing and Transwell assays, respectively. Apoptosis was detected by flow cytometry. mRNA and protein expression levels of NRF2(Nuclear factor erythroid 2-related factor 2), cGAS(cyclic GMP-AMP synthase), STING(stimulator of interferon genes), and NF-κB(nuclear factor kappa-light-chain-enhancer of activated B cells) were measured using qRT-PCR and Western blot, respectively. Protein localization was determined by immunofluorescence. Results: Compared to the model group (TNF-induced), the cell migration rate in the curcumin (CUR) groups was significantly decreased (p < 0.001), with a particularly marked reduction observed at a concentration of 50 μmol/L. Furthermore, as the concentration of curcumin increased, cell invasion capacity showed a significant dose-dependent decline. The apoptosis rate also significantly decreased with increasing curcumin concentrations, demonstrating a clear concentration-dependent effect. Mechanistically, curcumin treatment significantly upregulated the expression of NRF2 and inhibited the activation of its downstream cGAS-STING-NF-κB signaling pathway. Specifically, both mRNA and protein expression levels of NRF2 were markedly elevated (p < 0.001), while the mRNA and protein levels of cGAS, STING, and NF-κB were all significantly reduced (p < 0.001). Conclusions: Curcumin (CUR) can effectively inhibit the inflammatory response of synovial fibroblasts by activating the expression of NRF2 and subsequently suppressing the cGAS-STING-NF-κB signaling pathway. This study provides a new molecular mechanism target for curcumin in the treatment of RA and offers a theoretical basis for the intervention of autoimmune diseases with natural products. Full article

Background/Objectives: This study aimed to evaluate the autoregulatory capacity of optic nerve head (ONH) tissue blood flow in response to intraocular pressure (IOP) fluctuations during vitrectomy in patients with proliferative diabetic retinopathy (PDR). We hypothesized that impaired autoregulation of ONH tissue blood flow in response to intraoperative IOP fluctuations could contribute to subsequent ONH atrophy and the development of visual field defects in PDR patients following vitrectomy. Methods: We included five eyes from five patients with PDR (mean age 70.6 ± 9.0 years) undergoing 25-gauge pars plana vitrectomy. ONH tissue blood flow was quantitatively assessed using intraoperative laser speckle flowgraphy. Mean blur rate in the tissue area (MT), an indicator of ONH tissue blood flow, was measured at baseline (infusion pressure 0 mmHg), during sustained elevation to 25 mmHg (at 5 and 10 min), and 1 min after return to baseline (11 min). IOP was modulated using the IOP Control system of the Constellation platform. Results: Elevation of IOP to 25 mmHg significantly reduced ONH tissue blood flow, with MT decreasing by 29% at 10 min compared with baseline (p < 0.05, Dunn’s multiple comparisons test). After IOP returned to baseline, MT significantly recovered compared with the 10 min measurement (p < 0.05) and returned to levels not significantly different from baseline (p > 0.05). Conclusions: MT decreases during intraoperative IOP elevation in PDR undergoing vitrectomy, but recovers after the return to baseline pressure, suggesting preserved short-term autoregulatory capacity. Careful IOP management during vitrectomy remains important in eyes with PDR. Full article