Search Results (153)

Background and Objectives: Predicting postoperative refractive development after paediatric intraocular lens (IOL) implantation remains challenging due to continued ocular growth and interindividual variability. This scoping review maps current evidence on demographic, biometric, and surgical factors influencing postoperative myopic shift in children undergoing cataract surgery with IOL implantation. Methods and Materials: A systematic literature search was conducted in PubMed and Scopus from the last ten years through October 2025. Eligible studies included children (≤18 years) with congenital or developmental cataract undergoing primary or secondary IOL implantation that reported postoperative refractive change and its predictors. Titles, abstracts, and full texts were screened according to PRISMA-ScR guidelines. Data were charted on study design, age at surgery, follow-up duration, refractive and biometric outcomes, and associated predictors. Results: Twelve studies met the inclusion criteria. Younger age at surgery, shorter preoperative axial length, and unilateral cataract consistently predicted greater postoperative myopic shift. Reported myopic change ranged from approximately −1.8 D after 2 years to −11.6 D after 15 years of follow-up, correlating with the rate of axial elongation. Optical biometry and modern formulas (e.g., Holladay 1) showed lower absolute prediction error than manual A-scan or SRK-II calculations. Postoperative complications, especially glaucoma and visual axis opacification, were associated with greater refractive change. Conclusions: Postoperative myopic shift is a predictable, age-dependent feature of paediatric pseudophakia driven primarily by ocular growth dynamics. Standardised biometry, age-stratified refractive targeting, and integration of longitudinal growth models into IOL calculation algorithms may improve refractive predictability and visual outcomes in children. Full article

This study examines the effect of geometrically controlled anisotropy on the compressive behaviour of additively manufactured Voronoi cellular structures. Three configurations—an isotropic reference and two anisotropic variants generated by scaling the design domain along the Z-axis—were fabricated by stereolithography using a tough photopolymer resin. All specimens exhibited an approximate nominal porosity of 80%. Compressive tests were conducted along the X, Y, and Z directions in accordance with ASTM D1621. The elongated structure showed enhanced stiffness and strength when loaded parallel to the scaling axis, whereas the compressed structure exhibited improved performance in the transverse directions. The isotropic structure displayed similar responses in all axes. These results demonstrate that geometric scaling effectively induces directional mechanical anisotropy without altering relative density, offering a simple route to tailor the load-bearing behaviour of lightweight architected materials. Full article

Cellular senescence, a hallmark of aging, involves irreversible growth arrest and an enhanced senescence-associated secretory phenotype (SASP). It is often accompanied by mitochondrial dysfunction and altered inter-organelle communication. Using a chronic oxidative stress model in AML12 hepatocytes, we confirmed senescence by canonical assays (e.g., SA β-gal positivity and proliferation arrest) and observed a decline in the RNA-binding protein AUF1 (hnRNP D). AUF1 knockdown further amplified senescent phenotypes, including elongation of mitochondrial network, loss of mitochondrial membrane potential, reduced ATP level, and elevated mitochondrial reactive oxygen species (ROS). In addition, AUF1 knockdown weakened mitochondria-endoplasmic reticulum coupling and reduced mitochondrial Ca²⁺ load. At the molecular level, AUF1 binds to the 3′ untranslated regions (3′UTRs) of Opa1 and Mfn2 and limits their abundance, thereby coupling post-transcriptional control to mitochondrial dynamics. In gain-of-function experiments, ectopic expression of AUF1 attenuated Opa1/Mfn2 induction, restored mitochondrial network architecture, and preserved bioenergetic function under pro-senescent stimuli. Collectively, these findings support a model in which AUF1 preserves mitochondrial homeostasis and thereby restrains the mitochondria–senescence axis in hepatocytes. Full article

Calcium carbonate (CaCO₃) whiskers are promising materials for the high-value utilization of calcium-based resources. Here, aragonite whiskers were synthesized at a carbonation temperature of 90 °C using carbide slag ammonium leachate as the calcium source and CO₂ as the precipitant. The effects of control agents, carbonation temperature, Ca²⁺ solution feeding rate, CO₂ flow rate, and stirring speed on whisker morphology and aspect ratio were systematically investigated. Characterization via SEM and XRD revealed that the optimal conditions—carbonation temperature of 90 °C, Ca²⁺ feeding rate of 1.2 mL∙min⁻¹, ethanol addition of 2 mL, CO₂ flow rate of 150 mL∙min⁻¹, and stirring speed of 300 rpm—yielded uniform CaCO₃ whiskers with an average length of ~10 μm, an aspect ratio of ~24, and an aragonite purity of 99.42%. TEM confirmed that the whiskers are single crystals growing preferentially along the [001] direction. Hydroxyl groups were found to suppress lateral growth on the (200) facet, favoring elongation along the c-axis and enabling high-aspect-ratio whisker formation. These findings provide useful guidance for the scalable synthesis and industrial application of aragonite whiskers. Full article

Thermal elongation in high-speed motorized spindles constitutes a major source of machining error in five-axis machine tools, critically impacting machining precision. This study aims to develop and validate a cumulative thermal error compensation model for predicting spindle thermal elongation, subsequently enabling effective compensation via a dedicated control algorithm. Key thermal error factors, primarily spindle speed and cumulative thermal error, were identified through analysis. An innovative numerical prediction model incorporating these factors was established. Its performance was evaluated through experiments utilizing eddy-current displacement sensors for high-speed, high-precision thermal elongation measurement. The validation results demonstrated the model’s strong predictive capability: During spindle startup, prediction errors exhibited minor transients, stabilizing near zero once the operating speed was reached. Under dynamic speed changes, the maximum prediction error was only 1.28 μm, with the overall maximum residual error recorded at 2.04 μm. These findings confirm the model’s high accuracy. Furthermore, the model exhibits excellent generalization capability, delivering significant compensation effectiveness across diverse variable-speed operating conditions. This work successfully developed a highly accurate numerical model and a practical compensation strategy, significantly enhancing the positioning accuracy of high-speed spindles against thermal disturbances. The proposed approach offers substantial engineering utility for thermal error compensation in precision machining applications. Full article

The transport efficiency of anisotropic functional membranes is largely dictated by the geometry and orientation of their internal pores. In this study, a numerical finite-volume framework was developed to evaluate how elliptical pore eccentricity ($\epsilon cc$) and orientation influence charge transport and effective conductivity ($e_k$) within two-dimensional porous membrane microstructures. Canonical stochastic domains with controlled porosity were generated, considering parallel and perpendicular aligned configurations of the major pore axis relative to the imposed potential gradient. Results demonstrated a strong orientation dependence: under perpendicular alignment, the effective conductivity decreased by up to 70% as εcc increased from 0.5 to 0.999, while parallel alignment maintained at $e_k$ > 0.8 even for highly elongated pores. The aspect ratio $(b/a)$ was identified as a secondary geometric modulator producing opposite conductivity trends depending on orientation. Through isotropy-error analysis, a critical morphological threshold at $\epsilon cc$ ≈ 0.9 was found, indicating the onset of structural anisotropy and loss of isotropic transport. These results establish a quantitative structure–property relationship linking pore geometry to macroscopic transport performance. The proposed stochastic FVM-based approach provides a generalizable and computationally efficient tool for the design and optimization of anisotropic porous membranes used in electrochemical and energy-conversion devices. Full article

Background/Objectives: Plasma fibronectin (pFN) supports lung metastasis by promoting tumor cell invasion and survival in the context of blood clotting. Here, we set out to test if myeloid cells reiterate the clot-invasive mechanisms that have been established for tumor cells. Methods: We analyzed lung tissue sections from transgenic pFN-deficient mice for the co-localization of intravenously injected B16F1 tumor cells and the surrounding fibrin with myeloid cells, granulocytes, and macrophages. We also tested the role of pFN for macrophage differentiation and invasion in a three-dimensional fibrin matrix. Results: B16F1 melanoma cells, entrapped in the lungs of pFN-competent C57BL/6-Fn(fl/fl)Mx-Cre⁻ mice, were surrounded by a fibrin matrix, CD11b-positive myeloid cells, and Gr-1-positive granulocytes within 1 h of intravenous injection, while homing F4/80-positive macrophages to lung-born tumor cells occurred within 16 h. Compared to pFN-competent C57BL/6-Fn(fl/fl)Mx-Cre⁻ mice, the co-localization of CD11b⁺, Gr-1⁺, and F4/80⁺ cells with B16F1 cells was significantly reduced in the lungs of pFN-deficient C57BL/6-Fn(fl/fl)Mx-Cre⁻ mice. Mechanistically, we found that fibrin–fibronectin complexes promoted macrophage adhesion, differentiation, and invasion in clotted plasma. The pro-invasive function of fibrin–fibronectin depended on the upregulation of integrin β3 and Tie2 expression in macrophages and was reversed after knocking-down integrin β3 and Tie2 with siRNA. Conclusions: Our results suggest that blood clotting plays an important role in the recruitment of macrophages to circulating tumor cells and that the underlying mechanism of macrophage recruitment involves fibrin–fibronectin complexes, integrin β3, and Tie2. Full article

To elucidate the influence of the extrusion-based 3D printing of concrete on the tensile performance of polyethylene fibre-based engineered cementitious composites (PE-ECC), quantitative analyses of reinforcing filament alignment and pore morphology were carried out using backscattered electron (BSE) imaging and X-ray computed tomography (X-CT). A micromechanics analytical model based on microstructural characteristics was further employed to predict the tensile response of additively manufactured PE-ECC. Due to the extrusion process, fibres in 3D-printed PE-ECC were predominantly oriented along the printing path, resulting in a smaller average inclination angle compared with the randomly distributed fibres in cast specimens. Internal pores exhibited elongated flattened ellipsoidal shapes, with more pronounced anisotropy in axial lengths across the three principal directions. Taking the major semi-axis of the equivalent ellipsoidal voids as a representative pore parameter, the analytical model accurately reproduced the cracking strength, stress-strain evolution, and crack pattern of the printed PE-ECC. This extrusion process enhanced multiple cracking capacity and strain-hardening performance by improving fibre orientation, strengthening interfacial bonding, and altering matrix fracture toughness. The integration of micromechanical modelling with experimentally measured microstructural parameters effectively revealed the intrinsic mechanisms underlying the enhanced tensile behaviour of 3D-printed PE-ECC and provides theoretical support for the optimized design of fibre-reinforced cementitious composites in 3D printing. Full article

Characterized by social communication deficits and the presence of restricted and repetitive behaviors, autism spectrum disorder (ASD) is a significant neurodevelopmental condition. Genetic studies have revealed a strong association between ASD and numerous mutations that alter the function of key proteins, either through activation or inactivation. These alterations are widely hypothesized to affect neuronal morphogenesis; however, a comprehensive understanding of the specific molecular cascades driving these cellular and symptomatic changes remains lacking. In this study, we report for the first time that signaling through the atypical Rho family guanine-nucleotide exchange factor (GEF) Dock7 and ErbB2, an activator acting upstream of Dock7, drives the excessive elongation of neuronal processes observed in association with the ASD- and intellectual disability (ID)-linked semaphorin-5A (Sema5A) Arg676Cys variant (p.Arg676Cys). Knockdown of Dock7 using short hairpin RNA or inhibition of ErbB2 kinase signaling with a specific chemical inhibitor reduced this excessive process elongation in primary cortical neurons. Similar results were obtained in the N1E-115 cell line, a neuronal cell model that undergoes neuronal morphological differentiation. Moreover, inhibition of ErbB2-Dock7 signaling specifically decreased the overactivation of the downstream molecules Rac1 and Cdc42. These findings indicate that the ErbB2–Dock7 signaling axis plays a role in mediating the aberrant neuronal morphology associated with the ASD- and ID-linked Sema5A p.Arg676Cys. Targeting this pathway may therefore offer a potential approach to addressing the molecular and cellular developmental challenges observed in ASD. Full article

Caspases are known for their roles in cell death and inflammation. However, emerging evidence suggests they also mediate non-lethal processes, governed by a finely tuned balance of localization, activity, kinetics, and substrate availability. Given that many caspase substrates are implicated in mechanoadaptive processes, we investigated if caspases contribute to morphological adaptation of human pulmonary artery endothelial cells to fluid shear stress and other morphology-altering stimuli in vitro. Using selective inhibitors, we screened all major caspases for a role in endothelial cell adaptation to unidirectional laminar shear stress (15 dyn/cm², 72 h). Selective inhibition of caspase-6, but not other caspases, impaired morphological shear adaptation. Only 5.5% of caspase-6-inhibited cells shear-adapted vs. 75.2% of vector controls. Live-cell FRET imaging revealed progressive caspase-6 activation starting at 18 h of shear stress, coinciding with the onset of morphological remodeling. The active caspase-6 localized predominantly perinuclearly, while caspase-3 remained inactive throughout shear exposure. Caspase-6 inhibition did not affect elongation in response to alternative biomechanical or biochemical stimuli, including uniaxial cyclic stretch (5%, 1 Hz), spatial confinement on narrow micropatterned RGD-lines, or TNF-α stimulation, nor did it impair cell adhesion, directed migration, wound healing, or barrier recovery after wounding. Our study uncovers a previously unidentified role of caspase-6 as a non-apoptotic, mechanosensitive effector specifically required for shear-induced morphological adaptation of pulmonary artery endothelial cells, highlighting a novel regulatory axis in vascular mechanoadaptation. Full article

Al-Zn-Mg-Cu alloys are widely used as heat-treatable ultra-high-strength materials in aerospace structural applications. While conventional single-stage aging enables high strength, advanced performance demands call for precise microstructural control via multi-stage aging. In this study, we employ a combination of scanning transmission electron microscopy (STEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD) to investigate the microstructural evolution and its correlation with mechanical properties of AA7150 aluminum alloy subjected to two-step aging treatments, following a 6 h pre-aging at 120 °C. Through atomic-scale STEM imaging along the [110]_Al zone axis, we systematically characterize the precipitation behavior of GPII zones, η′ phases, and equilibrium η phases both within the grains and at grain boundaries under varying secondary aging (SA) conditions. Our results reveal that increasing the SA temperature from 140 °C to 180 °C leads to coarsening and reduced number density of intragranular precipitates, while promoting the continuous and coarse precipitation of η phases along grain boundaries, accompanied by a widening of the precipitation-free zone (PFZ). Notably, SA at 160 °C induces the formation of fine, uniformly dispersed nanoscale η′ precipitates in the alloy, as confirmed by XRD phase analysis. Aging at this temperature markedly enhances the mechanical properties, achieving an ultimate tensile strength (UTS) of 613 MPa and a yield strength (YS) of 598 MPa, while presenting an exceptionally broad peak-aging plateau. Owing to this feature, a moderate extension of the SA duration does not reduce strength and can further improve ductility, increasing the elongation (EL) to 14.26%. These results demonstrate a novel two-step heat-treatment strategy that simultaneously achieves ultra-high strength and excellent ductility, highlighting the critical role of advanced electron microscopy in elucidating phase-transformation pathways that inform microstructure-guided alloy design and processing. Full article

This study investigates the structural transformation from the γ-phase into the α-phase in bio-based nylon 5,6 fibers during in situ uniaxial stretching, using X-ray diffraction (XRD) and density functional theory (DFT) calculations. Initially, nylon 5,6 films exhibited a well-defined γ-phase crystalline structure, and the as-spun fibers also retained a γ-phase-dominant structure with partial coexistence of α-phase components. Due to the lattice similarity between the γ- and α-phases, phase separation was challenging in the direction perpendicular to the fiber axis (ab-plane). However, the analysis of the (004) diffraction peaks along the fiber axis (c-axis) enabled the quantitative evaluation of each crystalline component. As the stretching progressed, the α(004) peak intensity gradually increased, indicating a continuous γ-to-α structural transition. Furthermore, DFT calculations revealed that the α-phase has lower energy than the γ-phase, supporting the thermodynamic favorability of the phase transition during elongation. These results provide a comprehensive understanding of the crystalline structure and transformation mechanism in environmentally friendly nylon fibers from both experimental and theoretical perspectives, and offer foundational insights for developing nylon materials with desirable properties through the precise control of crystal phase structures. Full article

Structures that possess negative Poisson’s ratio are termed “Auxetic” structures. They elongate laterally on longitudinal–tensile loading and compress laterally on longitudinal–compressive loading. Auxetic structures are a composition of unit cells that are available in various geometries, which include triangular, hexa-triangular, re-entrant, chiral, star, arrowhead, etc. Due to their unique shape, these structures possess remarkably good mechanical properties such as shear resistance, indentation resistance, fracture resistance, synclastic behavior, energy absorption capacity, etc. However, they have poor load-bearing capacity. To improve the load bearing strength of these structures, this paper presents a numerical analysis of oriented re-entrant structured (ORS) beams with auxetic clusters aligned at various angles (0°, 45° and 90°), using Finite Element Methods. Oriented re-entrant unit cell clusters enclosed by a bounded frame were modeled and a three-point bending test was conducted to perform a comparison study on deformation mechanisms of the different oriented re-entrant honeycomb structures with honeycomb beams. The computational analysis of ORS beams revealed that the directional deformation and normal strain along the x-axis were the lowest in ORS45, followed by ORS90, ORS0, and honeycomb. Among all the beams, ORS45 displayed the best load-bearing capacity with comparably low mass density. Full article

The utilization of ocean wave energy through environmentally sustainable technologies plays a pivotal role in the transition toward renewable energy sources. Among such technologies, the Submerged Horizontal Plate (SHP) stands out as a viable option for clean power production. This study focuses on the system’s application in a region on the southern coast of Brazil, identified as a potential site for future installation. To investigate this system, a three-dimensional numerical wave tank was developed to simulate wave behavior and hydrodynamic loads using the Navier–Stokes framework in the computational fluid dynamics software ANSYS FLUENT 2022 R2. The volume of fluid approach was adopted to track the free surface. The setup for wave generation in the numerical wave tank was verified against analytical solutions to ensure precision and validated under the SHP’s non-oscillating condition. To represent the oscillating condition, boundary conditions constrained motion along the x- and y-axes, allowing movement exclusively along the z-axis. A parametric analysis of 54 cases, with varying geometric configurations, wave characteristics, and submersion depths, indicated that the oscillating SHP configuration elongated perpendicular to wave propagation, combined with specific wave conditions, achieved a theoretical mean efficiency of 76.61%. Full article

Understanding the combined gravi-phototropic behavior of plants is essential for space agriculture. Existing single-axis clinostats and gel-based grow media provide limited simulation fidelity. This study developed a Cloud-enabled triple-axis clinostat with built-in automated aeroponic and artificial photosynthetic lighting systems for Earth-based simulation under Martian gravity ranging from 0.35 to 0.4 g. Finite element analysis validated the stability and reliability of the acrylic and stainless steel rotating platform based on stress, strain, and thermal simulation tests. Arduino UNO microcontrollers were used to acquire and process sensor data to activate clinorotation and controlled environment systems. An Arduino ESP32 transmits grow chamber temperature, humidity, moisture, light intensity, and gravity sensor data to ThingSpeak and the Create IoT online platform for seamless monitoring and storage of enviro-physical data. The developed system can generate 0.252–0.460 g that suits the target Martian gravity. The combined gravi-phototropic tests confirmed that maize seedlings exposed to partial gravity and grown using the aeroponic approach have a shoot system growth driven by light availability (395–400 μmol/m²/s) across the partial gravity extremes. Root elongation is more responsive to gravity increase under higher partial gravity (0.375–0.4 g) even with low light availability. The developed soilless clinostat technology offers a scalable tool for simulating other high-value crops aside from maize. Full article