Search Results (1,109)

Deep learning algorithms have significantly reduced the computational time and improved the spatial resolution of particle image velocimetry (PIV). However, the models trained on synthetic datasets might have degraded performances on practical particle images due to domain gaps. As a result, special residual patterns are often observed for the vector fields of deep learning-based estimators. To reduce the special noise step by step, we employ a denoising diffusion model (FlowDiffuser) for PIV analysis. And a data-hungry iterative denoising diffusion model is trained via a transfer learning strategy, resulting in our PIV-FlowDiffuser method. Specifically, we carry out the following: (1) pre-training a FlowDiffuser model with multiple optical flow datasets of the computer vision community, such as Sintel and KITTI; (2) fine-tuning the pre-trained model on synthetic PIV datasets. Note that the PIV images are upsampled by a factor of two to resolve small-scale turbulent flow structures. The visualized results indicate that our PIV-FlowDiffuser effectively suppresses the noise patterns. Therefore, the denoising diffusion model reduces the average endpoint error ($AEE$) by $59.4\%$ over the RAFT256-PIV baseline on the classic Cai’s dataset. In addition, PIV-FlowDiffuser exhibits enhanced generalization performance on unseen particle images due to transfer learning. Overall, this study highlights transfer-learning-based denoising diffusion models for PIV. Full article

Background/Objectives: Atorvastatin, a lipophilic HMG-CoA reductase inhibitor used for lipid lowering, also exhibits considerable anti-neoplastic activity. Although previous studies have shown that glucose starvation can potentiate several anticancer chemotherapies, atorvastatin has not been rigorously investigated for its impact on metabolic vulnerabilities and the effects on cholesterol-rich lipid rafts in aggressive tumors. This work aims to evaluate the combined anticancer activity of atorvastatin with metabolic interventions, specifically glucose starvation, on U-87 (glioblastoma) and MDA-MB-231 (triple-negative breast cancer) cell lines. Methods: U-87 and MDA-MB-231 cancer cells were cultured in either normal or glucose-free media and treated with different concentrations of atorvastatin. The impact of atorvastatin on these cancer cells was analyzed by examining cell viability, apoptosis, cell cycle, and changes in membrane order within lipid rafts. Results: This study found that glucose starvation increased the sensitivity of U-87 cells to atorvastatin by lowering IC₅₀ values and eliciting arrest in the G1 phase of the cell cycle. MDA-MB-231 cells were less dependent on glucose for viability; however, atorvastatin consistently induced S-phase arrest across both metabolic states. Additionally, atorvastatin induced apoptosis in both U-87 and MDA-MB-231 cells, with the effect being more pronounced and dose-dependent in the fasting state with glucose. Interestingly, both Caspase-3 and Caspase-9 were consistently downregulated by atorvastatin in U-87 cells, regardless of the fasting state, corresponding to the induction of cell cycle arrest. Membrane lipid rafts exhibited decreased membrane order under glucose starvation, which was further decreased in response to atorvastatin in both cell lines, indicating a reduction in cholesterol. Conclusions: These results demonstrate that atorvastatin exhibits anticancer activity, characterized by both contextual and metabolic targeted effects, including a reduction in cancer proliferation, the triggering of cell cycle arrest via the downregulation of caspase pathways, and a decrease in membrane order. Notably, the combined activity of combining antilipemic agents with glucose-fasting provides potential metabolic strategies that could help create more effective and personalized approaches to cancer treatment. Full article

The urinary bladder is a primary target organ for environmental toxicants such as arsenic. The objects of this study were two-fold. First, we constructed a novel 3D urinary bladder mucosa model (3D-UBMM) composed of an overlying epithelium and a supporting subepithelial layer. Primary human bladder urothelial and fibroblast cells were immortalized by introducing the human CDK4^R24C and TERT genes. The construction of the 3D-UBMM involved incorporating immortalized fibroblast cells into a collagen raft, while immortalized urothelial cells were cultured at the air-liquid interface. This 3D-UBMM closely resembles the human bladder epithelium in terms of morphology and marker protein expression, including uroplakin 1b, P63, and cytokeratin 5. Second, using the 3D-UBMM we investigated the cytotoxicity of sodium arsenite (iAs^III) and dimethylarsenic acid (DMA^V). Exposure to iAs^III and DMA^V resulted in increased urothelial necrosis, increased γ-H2AX-positive cells, and reduced P63-positive cells, all in a dose–response manner. These findings affirm that this novel 3D-UBMM resembles the human bladder epithelium and offers a practical in vitro model for evaluating bladder toxicants and carcinogens, identifying mechanisms of carcinogenesis, and supporting hazard identification and risk assessment. Full article

As a critical factor in ice load calculation for marine structures in cold regions, the growth mechanism and mechanical properties of rafted ice urgently require clarification. This study systematically investigated the growth patterns and flexural strength characteristics of rafted ice through laboratory-prepared specimens. Experimental results indicate that the thickness of rafted ice exhibits a negative correlation with both ambient temperature and initial ice thickness during growth. Due to the higher porosity of its frozen layer, the density of rafted ice decreases by approximately 8% on average compared to single-layer ice. Three-point bending tests demonstrate that, under the combined effect of high tensile strength in the lower ice layer and energy absorption by the porosity of the frozen layer, the flexural strength of rafted ice ranges from 1.12 to 1.34 times that of single-layer ice. Full article

Novel universal bulk-fill composites with reversible addition–fragmentation chain-transfer (RAFT)-modulated polymerization continue the trend towards increasing simplification of the restoration process to facilitate the reconstruction of deep posterior restorations in 4 mm increments as well as anterior restorations through improved aesthetics. This study aims to assess the suitability of such materials for rapid curing (3 s) with high-radiant emittance in terms of degree of conversion (DC) and polymerization kinetics at relevant depths (2 mm vs. 4 mm). For this purpose, two newly introduced bulk-fill universal composites (Tetric^® plus Flow and Tetric^® plus Fill) were compared with already established fast-curing composites (Tetric^® Power Flow and Tetric^® Power Fill). DC was measured in real time over 300 s using ATR-FTIR spectroscopy. The temporal DC evolution was modelled using an exponential sum function. Novel bulk-fill composites showed DC results that were independent of the measured sample depth or curing mode. The polymerization kinetics of all composites are somewhat slower in the gel phase at moderate irradiance or when measured at deeper layers, but compensate for the differences in the glass phase, finally reaching equivalent DC values by the end of the 300-s observation period. These novel composites are therefore suitable for rapid curing (3 s) at high irradiance. Full article

Pedestrian localization is a fundamental sensing task for intelligent outdoor systems. To overcome the limitations of accuracy and efficiency in conventional binocular approaches, this study introduces a trinocular stereo vision framework that integrates template matching with geometric constraint optimization. The system employs a trinocular camera configuration arranged in an equilateral triangle, which enables complementary perspectives beyond a standard horizontal baseline. Based on this setup, an initial depth estimate is obtained through multi-scale template matching on the primary binocular pair. The additional vertical viewpoint is then incorporated by enforcing three-view geometric consistency, yielding refined and more reliable depth estimates. We evaluate the method on a custom outdoor trinocular dataset. Experimental results demonstrate that the proposed approach achieves a mean absolute error of 0.435 m with an average processing time of 3.13 ms per target. This performance surpasses both the binocular Semi-Global Block Matching (0.536 m) and RAFT-Stereo (0.623 m for the standard model and 0.621 m for the real-time model without fine-tuning). When combined with the YOLOv8-s detector, the system can localize pedestrians in 7.52 ms per frame, maintaining real-time operation (> 30 Hz) for up to nine individuals, with a total end-to-end latency of approximately 32.56 ms. Full article

The primary mechanism of non-steroidal anti-inflammatory drugs (NSAIDs) is inhibition of prostaglandin production mediated by cyclooxygenase. Given the possible association of cyclooxygenase-2, but not cyclooxygenase-1, with membrane lipid rafts, we assessed whether the lipid raft membrane interactivity of NSAIDs correlates with cyclooxygenase-2 selectivity. Lipid raft model membranes and reference membranes were prepared with 1,2-dioleoylphosphatidylcholine/sphingomyelin/cholesterol and 1,2-dipalmitoylphosphatidylcholine, respectively. After treating the membranes with 2–50 μM NSAIDs at pH 7.4, 6.5, and 5.5, fluorescence polarization was measured to determine their membrane interactivity. Conventional NSAIDs (diclofenac, ibuprofen, indomethacin, aspirin, and flurbiprofen) and Coxibs (lumiracoxib, etoricoxib, celecoxib, valdecoxib, and rofecoxib) decreased membrane fluidity, whereas Oxicams (meloxicam, piroxicam, tenoxicam, and lornoxicam) increased. Membrane effects of NSAIDs were so dependent on medium pH that they significantly increased with reducing pH from 7.4 to 5.5. Under inflammatory acidic conditions, the lipid raft membrane interactivity of NSAIDs was more likely to correlate with cyclooxygenase-2 selectivity than the reference membrane interactivity. It is hypothesized that NSAIDs may interact with lipid raft membranes to induce membrane fluidity changes with the potency corresponding to cyclooxygenase-2 inhibition, disrupting the structural and functional integrity of lipid rafts to affect the activity of cyclooxygenase-2 localized in lipid rafts, resulting in cyclooxygenase-2 selective inhibition. Full article

Gastroesophageal reflux disease (GERD) is associated with symptoms such as heartburn, resulting from gastric content reflux. Alginate-based raft-forming gel formulations represent a non-pharmacological strategy for GERD management by forming a floating gel barrier in the stomach. This study evaluated three commercial anti-reflux oral gel systems under simulated fed-state gastric conditions, using in vitro magnetic resonance relaxometry techniques. Magnetic resonance imaging (MRI) was performed in 0.01 M hydrochloric acid (HCl) to visualize gel raft formation, spatial structure, and spatial distribution of effective T₂ relaxation time. Nuclear magnetic resonance (NMR) relaxometry in 0.01 M deuterium chloride (DCl) measured T₁ and T₂ relaxation times of the protons that were initially included in the preparation to assess its molecular mobility within the gel matrix. Two formulations formed floating, coherent gels, whereas the remaining one exhibited only polymer swelling without flotation. In one case, relaxometry data revealed a solid-like component that can be detected, indicating enhanced mechanical stability. The performance of each formulation was influenced by interactions among alginate, bicarbonates, and calcium ions, which determined gel consistency and flotation behavior. MRI and NMR relaxometry in vitro provide valuable non-invasive insights into the structural and functional behavior of alginate-based gel formulations. This approach supports the rational design of advanced gel-based therapies for GERD by linking molecular composition with in situ performance. Full article

The scalable fabrication of hydrogels with high toughness and low hysteresis is critically hindered by oxygen inhibition, which typically produces brittle, highly crosslinked (HC) networks. This study presents an oxygen-tolerant photoinduced electron transfer–reversible addition–fragmentation chain transfer (PET-RAFT) strategy for synthesizing highly entangled (HE) polyacrylamide hydrogels under open-vessel conditions. By optimizing the water-to-monomer ratio (W = 3.9) and introducing lithium chloride (LiCl) for spatial confinement, we achieved a fundamental shift in mechanical performance. The optimized HE hydrogel exhibited a fracture energy of 1.39 MJ/m³ and a fracture strain of ~900%, starkly contrasting the brittle failure of the HC control (W = 20, C = 10⁻²) at ~50% strain. This represents an order-of-magnitude improvement in deformability. Furthermore, the incorporation of 15 wt% LiCl amplified the HE hydrogel’s fracture energy to 2.17 MJ/m³ while maintaining its low hysteresis. This method enables the rapid, scalable production of robust, transparent thin films that exhibit dual passive cooling via radiative emission (>89% emissivity) and evaporation, rapid self-healing, and reliable strain sensing at temperatures as low as −20 °C. The synergy of entanglement design and confinement engineering establishes a versatile platform for manufacturing multifunctional hydrogels that vastly outperform their crosslink-dominated predecessors. Full article

Myalgic Encephalomyelitis (ME) is a complex, multisystem disorder with poorly understood pathophysiological mechanisms. SMPDL3B, a membrane-associated protein expressed in renal podocytes, is essential for lipid raft integrity and glomerular barrier function. We hypothesize that reduced membrane-bound SMPDL3B may contribute to podocyte dysfunction and impaired renal physiology in ME. To investigate this, we quantified soluble SMPDL3B in plasma and urine as a surrogate marker of membrane-bound SMPDL3B status and assessed renal clearance and plasma metabolomic profiles. In a cross-sectional study of 56 ME patients and 16 matched healthy controls, ME patients exhibited significantly lower urine-to-plasma ratios of soluble SMPDL3B and reduced renal clearance, suggesting podocyte-related abnormalities. Plasma metabolomics revealed dysregulation of metabolites associated with renal impairment, including succinic acid, benzoic acid, phenyllactic acid, 1,5-anhydroglucitol, histidine, and citrate. In ME patients, plasma SMPDL3B levels inversely correlated with 1,5-anhydroglucitol concentrations and renal clearance. Multivariable modeling identified the urine-to-plasma SMPDL3B ratio as an independent predictor of clearance. Female ME patients showed more pronounced SMPDL3B alterations, reduced clearance, and greater symptom severity. Non-linear associations between soluble SMPDL3B and lipid species further suggest systemic metabolic remodeling. These findings support soluble SMPDL3B as a potential non-invasive biomarker of renal-podocyte involvement in ME, highlighting sex-specific differences that may inform future therapeutic strategies. Full article

CD44, a multi-isoform adhesion receptor for hyaluronic acid (HA), plays a crucial role in regulating cell interactions with the extracellular matrix, cell migration, differentiation, and survival in both physiological and pathological contexts. Accumulating experimental evidence suggests that CD44 is not merely a passive marker of mesenchymal cell activation but rather an active signaling hub driving fibrosis in many organs, including the lung, skin, heart, and liver. Its involvement in fibroblast differentiation into myofibroblasts, as well as induction of the invasive phenotype of these cells, shows striking analogies to the mechanisms of epithelial-to-mesenchymal transition (EMT) known from cancer progression. In this paper, we discuss both the molecular mechanisms of CD44-dependent signaling (including through EGFR, MAPK/ERK, CaMKII, lipid rafts, and Smad) and the influence of its modulation (knockout, antibodies, blockade of HA synthesis) on the course of fibrosis in in vitro and in vivo models. In addition, we present the influence of environmental pollutants—such as heavy metals, particulate matter, endocrine disruptors, and microplastics—on the activation of the HA-CD44 axis in connective tissue, with particular emphasis on their role in the induction of chronic inflammation, EMT, and extracellular matrix deposition. The collected evidence suggests that CD44 serves as a central integrator of inflammatory and fibrogenic signals, and its pharmacological modulation may represent a novel therapeutic strategy for treating fibrotic diseases and chronic inflammatory conditions. Full article

Herein, we report a combined computational and experimental investigation into the recently reported universal pyrazole-based reversible addition-fragmentation chain transfer (RAFT) agents (Z−C(=S)−S−R, where Z is 3,5-dimethyl-1H-pyrazol-1-yl), which can mediate controlled radical polymerization of a broad scope of monomers without the need for an additional initiator or catalyst. The results reveal that the high molar absorption coefficient and efficient photolysis kinetics of pyrazole-based chain transfer agents (CTAs) under blue light (${\lambda }_{\max }$ = 465 nm) enable rapid radical generation, underpinning ultrafast polymerization of acrylates, acrylamides, methacrylates, and N-vinylpyrrolidone (NVP). While the efficient light absorption is attributed to structural dissimilarity between the Z group and the S–R group (which breaks the local symmetry of the C=S group), the fast photolysis originates from favorable $\pi$ electron donation from the Z group to the C=S group. Meanwhile, the $\pi$ electron donation is still weaker than in xanthates, which explains the excellent control of a wide range of monomers, except methacrylates. This work establishes design principles for next-generation CTAs for ultrafast and monomer-universal photoiniferter RAFT polymerization. Full article

Cellular organization relies on both membrane-bound organelles and membraneless biomolecular condensates formed through liquid–liquid phase separation. Recent discoveries reveal intricate coupling between lipid membrane organization and condensate assembly, reshaping our understanding of cellular compartmentalization. This review synthesizes multidisciplinary research using advanced techniques including super-resolution microscopy, fluorescence recovery after photobleaching, and in vitro reconstitution to examine lipid-condensate interactions. Lipid membranes serve as nucleation platforms that reduce critical concentrations for condensate formation by orders of magnitude through membrane anchoring and thermodynamic coupling, creating specialized microenvironments that substantially enhance enzymatic activities. Key regulatory mechanisms include phosphorylation-driven assembly and disassembly, membrane composition effects from cholesterol content and fatty acid saturation, and environmental factors such as calcium and pH. These interactions drive signal transduction through receptor clustering, membrane trafficking via organized domains, and stress responses through protective condensate formation. Dysregulation of lipid-condensate coupling, including aberrant phase transitions and membrane dysfunction, underlies metabolic disorders and neurodegenerative diseases. This coupling represents a fundamental organizing principle with significant therapeutic potential. Current challenges include developing quantitative methods for characterizing condensate dynamics in complex cellular environments and translating molecular mechanisms into clinical applications. Future progress requires interdisciplinary approaches combining advanced experimental techniques, computational modeling, and standardized protocols to advance both fundamental understanding and therapeutic innovations. Full article

The flora of Haida Gwaii includes many macroalgal species, initially assumed endemic, which are largely absent from southern British Columbia but which were subsequently collected in California. One explanation for these disjunct distributions is the kelp conveyor hypothesis, which proposes non-buoyant macroalgae hitchhike on kelp rafts from central California to Haida Gwaii. Using mitochondrial COI-5P data, we adopt a weight-of-evidence approach and summarize broad patterns of allelic distribution and genetic differentiation across 11 species of red algae collected in California, Haida Gwaii and southern Vancouver Isl., British Columbia, to assess the impact of the kelp conveyor hypothesis. Although this hypothesis was based on species with disjunct distributions, we emphasize species with continuous distributions. In support of this hypothesis, we demonstrate low genetic differentiation between Haida Gwaii and California in 9 of 11 species consistent with significantly higher gene flow than from California to Vancouver Isl., and 13% of all alleles observed on Haida Gwaii were disjunct. These observations are consistent with predictions of the kelp conveyor hypothesis. Results here shed light on a previously cryptic source of gene flow which has impacted a considerable proportion of the red algal flora of Haida Gwaii. Full article

The Strait of Sicily represents a biogeographically rich and complex region. The diverse geological origin and past continental connection of its islands have shaped a highly heterogeneous fauna, mainly composed of both African and European taxa. The Italian sea-slater, Ligia italica (Fabricius, 1798), is a small isopod inhabiting rocky shores of the Mediterranean Sea, Black Sea, and Atlantic Ocean. Despite its wide distribution, the phylogeography of this species is poorly understood, with limited available data suggesting a remarkable level of cryptic diversity. In this study, we investigated the mitochondrial genetic diversity (COX1) of L. italica across nine Italian and Maltese islands across the Strait of Sicily, aiming to clarify the biogeographic patterns underlying the distribution of these insular populations. Our results reveal an unexpectedly high genetic diversity within our study area, with eight different haplogroups, each characterized by low internal genetic variation and mutual distances ranging from 5.5% to 17.9%. These values are comparable to those associated with species-level rank within the genus Ligia. Overall, the phylogenetic relationships between the lineages appear well supported; however, the same relationships are not clearly correlated with geographic proximity or connectivity among the sampled localities. The distribution patterns of some of the detected haplogroups suggest possible passive dispersal mechanisms (e.g., rafting), while others indicate more intricate biogeographic scenarios. The overall diversity of L. italica within the Strait of Sicily, as well as the unclear origin of some insular populations, cannot be fully explained with the current data. In particular, the high genetic structure observed within the Maltese Archipelago, may partially reflect human-mediated dispersal (e.g., maritime transport), possibly involving source populations that remain unsampled or genetically uncharacterized. Our results highlight that the Strait of Sicily can be considered a diversity hot spot for L. italica and support the designation of this taxon as a putative species complex, with a cryptic diversity worthy of an exhaustive taxonomic revision. Full article