Search Results (562)

Mesenchymal stromal cells (MSCs) are central to regenerative medicine and advanced therapies. However, the absence of consensus on reporting kinetic parameters, such as population doubling level (PDL), population doubling time (PDT), and the reliance on passage number alone obscures biological age and manufacturing history, and limits correlation of potency with expansion dynamics. Here, we clarify the distinctions among passages, PDL, PDT, and replication rate; we synthesize evidence that identical passage numbers can conceal multifold differences in cumulative doublings, with downstream effects on transcriptomic stability, and immunomodulatory performance. We further highlight culture determinants, oxygen tension, seeding density, media formulation, surface/bioreactor systems, and early niche mimetic stimuli, that shape proliferative kinetics and cellular aging trajectories in WJ-MSCs. Critically, we propose extracellular vesicles (EVs) as sensitive functional readouts of bioprocess stress and expansion history: EV quantity can increase while functional bioactivity declines, and EV miRNA cargo captures cell state programs not evident from minimal identity markers. To address these gaps, we recommend a reporting framework that incorporates: (1) culture conditions, (2) passage number and PDL at harvest, and (3) functional consequences of expansion. Adopting kinetic metrics beyond passage number will harmonize data capture and enable pooled analyses, accelerating clinical translation while safeguarding patient outcomes. Full article

Higher turbine inlet temperatures improve cycle efficiency but intensify blade thermal loading, so internal passages rely on turbulators that raise convection within coolant pressure budgets. Streamwise sinusoidal ribs introduce curvature and spanwise phasing beyond straight transverse bars, yet reconciled multi-row thermal–hydraulic data for such layouts in high-aspect-ratio blade-cooling analogues remain scarce. Steady three-dimensional computational fluid dynamics (CFD) of turbulent airflow in a 4:1 rectangular channel with uniform heat flux on one ribbed wall are applied to compare nine parametric sinusoidal-rib layouts and one transverse baseline at bulk Reynolds numbers from 20,000 to 90,000. The normalized Nusselt number ($Nu/N{u}_0$), Fanning friction factor ($f/f_0$), and composite thermal–hydraulic performance indices quantify the trade-off. Several layouts outperform the transverse baseline; a streamwise-increasing rib-height schedule achieves the highest pressure-drop-weighted index, whereas a large-amplitude uniform waviness gives the best heat-transfer-dominated index. The parametric matrix indicates when streamwise waviness merits further study in ribbed passage design. Full article

Highway slope instability under coupled traffic and environmental loading poses critical threats to transportation safety in mountainous regions, where dynamic vehicular forces interact with complex geological conditions in ways that single-modality monitoring cannot fully resolve. This study proposes MMDF-DEWS, a multi-modal data fusion and deep learning-based early-warning system that, for the first time, treats quantified traffic-loading parameters as a first-class input modality alongside Interferometric Synthetic Aperture Radar (InSAR) displacement, Global Navigation Satellite System (GNSS) measurements, and embedded geotechnical sensor outputs. A hybrid Transformer–bidirectional LSTM backbone with hierarchical attention-guided fusion enables the model to capture both long-range temporal deformation trends and short-term dynamic responses triggered by heavy-vehicle passage. To guard against over-fitting on a limited number of instability events, we adopt chronological training/validation/test partitioning, five-fold cross-validation for hyper-parameter selection, stratified focal-loss training, and cross-dataset evaluation on two independent public benchmarks: the Three Gorges Reservoir Area Landslide Monitoring Dataset (TGRA-LMD) and the European Ground Motion Service Sentinel-1 (EGMS-S1) dataset. The framework outperforms six state-of-the-art baselines by 4.7–11.2% in F1-score, and ablation studies confirm that the explicit inclusion of traffic-loading features alone improves Warning-class recall by 6.3 percentage points, demonstrating a direct and physically grounded link between cyclic vehicular loading and slope-state prediction. The system satisfies operationally relevant engineering targets for warning lead time and false-alarm rate, and provides interpretable attention maps suitable for transportation-authority decision support. Full article

The dynamics of landfalling tropical cyclones are not yet fully understood. In this study, ground-based observations were conducted using L-band radar, lidar and radiosonde during tropical cyclone Wutip. The L-band radar winds were corrected using lidar wind, and an objective analysis wind was derived from both the L-band radar and lidar data. Furthermore, we analyzed radiosonde profiles from a nearby station. The relative humidity was found to be higher in the lower boundary layer. Using the air temperature and humidity data, we computed the buoyancy frequency, and the Richardson number, which indicates shear instability in air turbulence. Within the altitude range of 15 km, the lower boundary layer exhibited a relatively low Richardson number. The integrated multi-source observations captured vertical profiles of wind, air temperature and relative humidity, and further revealed vertical wind shear, atmospheric stratification and associated shear instability throughout the passage of tropical cyclone Wutip. Full article

Following the passage of the Agriculture Improvement Act of 2018, demand for accurate cannabinoid quantification in hemp flowers has increased to ensure regulatory compliance. Liquid chromatography–tandem mass spectrometry (LC–MS/MS) using a triple-quadrupole mass spectrometer provides high sensitivity and selectivity and is well suited for this purpose; however, a review of the literature indicates that many published LC–MS/MS methods target only a limited number of cannabinoids, and reliable differentiation of structural isomers remains challenging. In this study, an LC–MS/MS method was developed for the simultaneous quantification of eighteen cannabinoids in hemp flowers. Baseline chromatographic separation of structural isomers enabled reliable differentiation of compounds with highly similar fragmentation patterns and allowed the use of the most sensitive multiple reaction monitoring (MRM) transitions for quantification. Both positive and negative ionization modes were employed to achieve optimal sensitivity using dynamic polarity switching within a single analytical run. Following validation in accordance with ISO/IEC 17025, the method was applied to a proficiency test hemp sample and six commercial hemp samples, demonstrating excellent time efficiency (11 min for 18 cannabinoids) and an exceptionally wide calibration range (8–5000 ng/mL, corresponding to 0.032–20% (w/w) for all cannabinoids). Full article

Tungsten carbide and cobalt cutting tools require low surface roughness to improve cutting performance by reducing the wear from machining friction. While this is achieved by conventional manufacturing processes (pressing and sintering, grinding), with additive manufacturing processes it is more difficult (layer height, printing strategy). Since less costly and more sustainable solutions (without lubricants) are being studied as alternatives to conventional processes, a complementary technology (laser ablation) is suggested for the additive manufacturing of green WC-10Co. In this study, material extrusion (MEX) was used to produce green WC-10Co 3D objects, followed by laser ablation (50 W ytterbium fiber laser, 800–1100 nm wavelength) on their surface. Different laser strategies and parameters (power, speed, frequency, distance between lines, number of passages) were tested to find the most suitable. Most combinations were excluded by initial visual inspection, while the best ones were measured with a contact and non-contact profilometer. Further analysis was made on the composition and microstructure (with techniques such as Raman spectroscopy, scanning electron microscope, x-ray diffraction, and hardness indentation) to study what the interaction with the laser changed on the surface. Results show that with a combination of 50 W laser power, 1000 mm/s laser speed, 2000 kHz laser frequency, 0.1 mm distance between lines and three laser passages, it was possible to achieve a surface roughness of 0.6 µm (Sa) for the sintered WC-10Co, produced by MEX. No η-phase and graphite were detected, as well as microporosity and fissures. Full article

Technical documents differ from general text corpora in ways that complicate retrieval-augmented generation (RAG). Evidence for a single answer is often distributed across numbered clauses, tables, figures, captions, and ordered procedures rather than expressed in one passage. Standard RAG pipelines typically flatten these elements into independent chunks. This can break the document relations needed for exact evidence tracing. We introduce TechDocRAG, a relation-preserving framework for technical document question answering. The framework represents each document as a heterogeneous element graph and aligns three retrieval views for each element: technical identifiers, semantic summaries, and raw evidence. At query time, retrieval proceeds from identifier-aware recall to summary-level reranking and raw evidence bundling. We evaluate TechDocRAG on four benchmarks with more than 7500 evaluated question–answer pairs covering product manuals, engineering documents, and long multimodal PDFs. Across the suite, TechDocRAG improves the mean end-to-end score by 20.3 points over the strongest flat baseline and by 9.3 points over the strongest non-flat baseline. On the evidence-annotated subset, the strict raw evidence hit rate increases from 0.510 to 0.942. Resource profiling shows query time latency comparable to standard hybrid retrieval. Robustness tests show gradual degradation under relation loss, but clear sensitivity to severe identifier corruption. Overall, the results indicate that reliable RAG for technical documents depends less on retrieving more passages than on preserving the relations that make evidence interpretable. Full article

Typhoon passages typically induce significant upper-ocean responses, especially on the right side of the typhoon track. However, how mesoscale eddies modulate this left–right asymmetry remains insufficiently understood. Using high-resolution remote sensing data and reanalysis datasets, this study examines the impacts of a mesoscale eddy dipole influenced by Typhoon Ma-on (2011). The study finds that: (1) The eddy responses exhibit significant asymmetry: during Typhoon Ma-on (2011), the amplitude, circulation speed, and radius of the left side cyclonic eddy (CE) showed anomaly increases of 8.6 cm, 4.3 cm/s, and 54.3 km, respectively, whereas those of the right-side anticyclonic eddy (AE) showed anomaly decreases of 2.9 cm, 4.8 cm/s, and 13.9 km. (2) Mesoscale eddies modulate sea surface cooling with significant left–right asymmetry, differing from the conventional pattern of stronger right-side cooling. The left side CE enhanced surface cooling by up to 2.38 °C, while the right-side AE exerted a suppressing effect, with a cooling magnitude of 0.96 °C. (3) Within the CE, a significant negative temperature anomaly develops below about 20 m. Despite a relatively high Richardson number ($Ri$) and weak vertical shear that suppress excessive turbulent mixing, negative $W_s$-driven upwelling dominates, allowing cold water to be efficiently uplifted and maintaining or intensifying surface cooling. In contrast, the AE exhibits surface cooling but persistent positive anomalies below about 40 m, reflecting the partial retention of its subsurface warm water. In this case, reduced $Ri$ and enhanced shear instability promote stronger vertical mixing, enabling subsurface heat to be transported upward, thereby offsetting and weakening the surface cooling signal. Full article

Tuned mass dampers (TMDs) are commonly used to reduce excessive vibrations in engineering structures. Although their vibration control performance has been widely studied, the reliability of TMD-equipped structures under stochastic excitations has not been sufficiently investigated. In practical applications, random loads and system uncertainties may significantly affect structural safety, and an efficient evaluation of failure probability remains a challenging task. Thus, the applications of these methods are greatly limited in vibration control. In this work, the structural reliability of systems equipped with TMDs is analyzed by adopting the first-passage time (FPT) as the failure criterion. Numerical investigations are performed on continuous beam models with TMDs under different types of stochastic excitation. In addition, an experimental study on a two-story steel frame structure is conducted to further examine the reliability performance of TMD-controlled systems. To reduce the computational cost associated with Monte Carlo simulation, a data-driven classification method is employed to approximate the failure domain based on a limited number of samples. The results indicate that the proposed approach enables accurate reliability estimation with a substantial reduction in computational cost, making it suitable for large-scale reliability analysis of vibration-controlled structures under stochastic excitation. The experimental results further demonstrate the applicability of the proposed reliability assessment method for practical vibration control problems. Full article

The number and variety of images of reading in the Investigations suggest that, for Wittgenstein, reading is an essential part of our natural history and of the human form of life. Further, his treatments of reading show that different forms of reading express and sustain different forms of life. This essay explores what the Investigations reveals as the existential stakes of different modes of reading. Beginning with Wittgenstein’s opening engagement with Augustine, it argues that in the Investigations, as in the Confessions, different modes of reading both bespeak, and open us to, blessed or cursed forms of life. It then develops extended interpretations of individual passages in order to detail some specific shapes of, and conditions governing, modes of reading tied to these blessed or cursed forms of life. Finally, given these existential stakes of reading, it examines how the Investigations itself asks to be read and outlines specific ways in which its notorious difficulty and obscurity are essential to achieving its philosophical aims and, in particular, to promoting an ongoing practice of reading through which we are able to awaken to the wonder of our lives in language. Full article

An automotive welding unit is a modular production cell within a welding workshop that integrates industrial manipulators, welding equipment, fixtures, and control systems to perform specific welding and assembly tasks. A large number of industrial manipulators are utilized in the automotive welding unit. The capability to quickly plan a short and collision-free path in the workspace of the manipulator is of great importance for improving the manipulator’s intelligence level and production efficiency. The RRT* algorithm, based on random sampling, has been widely applied in path planning for high-dimensional manipulators due to its probabilistic completeness and powerful exploration capabilities. However, the RRT* algorithm performs poorly in spaces containing narrow passages. Research on the practical application of path planning for 6-DOF manipulators is still insufficient, particularly in planning posture. To solve these two problems, an improved RRT* algorithm is proposed in this paper. New sampling and node connection strategies are designed to improve the expansion and convergence speed of the random tree in spaces containing narrow passages. A distance-constrained posture quaternion interpolation method is presented to generate smooth and continuous paths for manipulators of the automotive welding unit. Simulations and experiments are carried out to validate the proposed method, which confirms that the method can plan collision-free paths for manipulators more quickly compared to other methods. Full article

Boundary Layer Ingestion propulsors operate in an adverse aerodynamic environment with high levels of distortion. With the purpose of extending the operating range of transonic fan rotors for BLI applications, in this paper we present an optimisation study focused on blade profiles design under different working conditions. Quasi-2D blade sections are optimised using a genetic algorithm and numerical simulations, by varying the camberline and thickness distribution. A method to efficiently achieve a combination of total pressure ratio at a given relative inlet Mach number is devised. The isentropic efficiency is optimised at the design point, concurrently with the stall total pressure ratio at a lower inlet Mach number, in a multi-objective fashion. Pareto-optimal profiles exhibit a moderate leading edge concavity for high efficiency and a straighter fore part with increased trailing edge deflection for higher compression at stall. Optimised airfoils are used in a preliminary three-dimensional evaluation with a realistic BLI inflow, in which the unsteady full-annulus analysis corroborates the approach of the sectional optimisation, also showing the possibility of estimating the integral performance of the machine with a simplified approach based on a single-passage simulation with a circumferential-averaged inflow distribution. Full article

Background/Objectives: Many products that claim to have anti-aging effects have been reported, but their relative potency is not clear. In this study, the in vitro replicative lifespan extension (RLE) activity of various groups of physiologically active substances was compared by using the updated “overlay method”. Methods: Human dermal and periodontal ligament fibroblasts (HDFa, HPLF) were inoculated into the inner 60 wells of 96-well microplate, surround by sterile water to prevent the water evaporation. At Day 1 and Day 8, the cells were overlayed with wide ranges of concentrations (0.01–100 µM) of samples without medium change. Viable cell number was measured by the MTT method at Day 15 and then corrected for the variation in cell growth due to the location of inoculated cells. The RLE value was calculated as the maximum cell proliferation rate relative to the control. Results: Cell density of HDFa and HPLFs at subculture decreased with the passage number, and their growth was stopped at 56 or 85 population doubling levels (PDLs), respectively. Hydrocortisone showed the highest RLE values among six hormones, followed by three plant extracts, sodium ascorbate and quercetin. On the other hand, other antioxidants, chlorogenic acid, phenylpropanoids, vanilloids, and bacterial products showed little or no RLE effects. However, for HPLF cells, hydrocortisone did not show RLE effects while oxytocin showed slight stimulation. Conclusions: When differences in proliferation due to cell seeding position were corrected, the biphasic dose response curve of most of the compounds significantly reduced. The present study suggests the significant role of hormones for the regulation of the long-term aging process. To confirm systemic or clinical anti-aging effects, further in vitro and in vivo experiments are needed. Full article

Cultured urine-derived cells (UDCs) have been proposed as a source of material for the RNA-based molecular diagnosis of genetic disorders. Previous studies have shown that UDCs can be clonally expanded, passaged, frozen, regrown and have some stem cell characteristics, but their anatomic origin and diagnostic utility remain insufficiently explored. In this study, we cultured UDCs from 40 individuals (aged 4 to 20 years; 21 females) and extracted RNA for sequencing. We compared UDC gene expression to that of marker genes of the kidney and urinary tract segments. UDC gene expression most closely matched marker genes of parietal epithelial cells that line the inner surface of Bowman’s capsule in the kidney glomerulus. UDCs expressed VCAM1 (CD106) and POUF51 (OCT4), consistent with a progenitor cell type. UDCs also expressed 54.4% of 3125 OMIM-listed disease-causing genes. This indicated that UDCs can be used to diagnose a similar number of genetic disorders as skin fibroblasts and a wider range of genetic disorders than can be analysed by RNA extracted from whole blood. In conclusion, UDCs are a non-invasive cell source for RNA sequencing that is suitable for investigating a broad range of conditions. Full article

The runner of a pump turbine features a relatively flat structural configuration. The clearance cavities formed between the upper crown, lower band, and surrounding stationary components play a critical role in its dynamic behavior and operational stability. Consequently, a detailed modal analysis of the runner is essential to ensure safe and stable operation. In this study, an acoustic–structure coupling method is adopted to investigate the wet modal characteristics of the pump-turbine runner, explicitly accounting for the added mass effect induced by the fluid in the external flow passages. By systematically varying the geometric parameters of the upper crown clearance cavity, the influence of seal clearance dimensions on the runner’s modal characteristics is examined. The results demonstrate that the radial clearance and the axial height of the seal cavity are the most influential parameters, reducing natural frequencies by up to 15.85% and 16.93%, respectively. The pitch of the seal teeth shows a secondary yet notable effect, inducing a frequency variation of 13.73%. In contrast, local labyrinth seal parameters, such as the number of teeth and tooth width, have a comparatively limited effect. This study provides practical guidance for vibration risk prediction, anti-resonance design, and operational stability assessment of high-head, large-capacity turbine runners by revealing the quantitative relationship between geometric parameters and modal frequencies. Full article