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XGBoost algorithm for predicting heat transfer coefficient of saturated flow boiling in mini/micro-channels
No full textAccurate prediction of the heat transfer coefficient in saturated flow boiling within mini/micro-channels is the most critical factor in designing thermal systems for high-heat-flux devices. This study proposes a machine learning technique to predict the heat transfer coefficient of saturated flow boiling using the XGBoost (eXtreme Gradient Boosting) algorithm. The database used in this study consists of 11,470 pre-dryout data points, obtained by removing 1878 post-dryout data points from a total of 13,348 data points collected from 41 sources, employing an XGBoost incipience dryout predicting model. The dataset includes 23 working fluids, hydraulic diameters ranging from 0.19 mm to 6.50 mm, mass flow rates from 19.45 kg/m²s to 1608 kg/m²s, and saturation temperatures from -40 °C to 201.37 °C. The permutation feature importance (PFI) and SHapley Additive exPlanations (SHAP) values were used for feature selection, while Optuna was used for hyperparameter tuning. A total of seven training features— Prf, xdi, Pred, Frfo, Bo, Prg , and Frtp —were selected and used to develop the model. The model achieved a mean absolute error (MAE) of 7.18 %, demonstrating superior predictive performance compared to existing empirical correlations and other machine learning algorithms. This result confirms that XGBoost is an effective and reliable algorithm for predicting the heat transfer coefficient of saturated flow boiling in mini/micro-channels. © 2025 Elsevier Ltd.FALSEsciescopu
Levan-stabilized Prussian blue nanoparticles targeting the CD44 receptor for the effective treatment of acute kidney injury
No full textAcute kidney injury (AKI) is a prevalent disease characterized by sudden loss of renal function. Nanozymes have emerged as promising therapeutic candidates because of their intrinsic reactive oxygen species (ROS)-scavenging capabilities and anti-inflammatory efficacy. However, their clinical translation has been hindered by limited bioavailability and lack of targeted tissue specificity. In this study, ROS-scavenging Prussian blue nanozymes were stabilized with levan polysaccharide (L-PB) to improve their colloidal stability, biocompatibility, and inflammation site-targeting ability. The resulting L-PB exhibited a stable hydrodynamic diameter of similar to 100 nm under physiological conditions for up to 2 weeks. In vitro assays confirmed the biocompatibility, effective ROS-scavenging activity, and significantly higher cellular internalization of L-PB than that of Prussian blue stabilized with bovine serum albumin (B-PB). In a glycerol-induced murine model of AKI, L-PB demonstrated selective accumulation in CD44 receptor-overexpressing injured kidneys and exhibited excellent therapeutic effects by mitigating oxidative stress and inflammation, with minimal systemic toxicity compared with B-PB. These findings indicate that L-PB, with CD44 active targeting, has potential as a novel targeted AKI therapeutic, enabling efficient treatment of various inflammation-related diseases.FALSEsciescopu
Experimental manifestation of topological lifshitz transition by observing thickness-dependent shift of plasma frequency in topological semimetals
No full textTopological semimetals (TSMs), which host massless Dirac fermions, offer a promising platform to explore quantum phenomena. Topological Lifshitz transitions (LTs) are ubiquitous, with applications spanning ferromagnetism, superconductors, topological materials, and even high-energy physics. In this study, we observe a topological LT in epitaxial thin films of Bi0.96Sb0.04 without external excitations, where the TSM characteristics are retained throughout the transition. The LT is revealed by a thickness-dependent shift in plasma frequency, measured through terahertz (THz) optical conductivity spectroscopy. Only in ultrathin two-dimensional (2D) films (thickness <= 10 nm) does the emitted THz wave show a clear difference between left- and right-circularly polarized light, a circular photogalvanic effect that is a hallmark of Weyl semimetals. Such behavior signals a topological phase transition caused by inversion symmetry breaking in films with thickness <= 10 nm, thereby providing experimental confirmation of the LT in TSMs. The optical conductivity shows a similar critical change at a thickness of 10 nm, which matches the thickness-dependent trend in electrical conductivity measured in simple planar devices. Finally, a strong correlation is observed between the plasma frequency and carrier density in this 2D regime, consistent with prior theoretical predictions.FALSEsciescopu
Interleukin-18 binding protein deficiency results in gut microbiota dysbiosis and aggravated diet-induced MASH in mice
No full textBackground & Aims
MASLD/MASH are now the most prevalent hepatic disorders worldwide. Growing evidence implicates physiological alterations in the gut-liver axis and gut microbiota dysbiosis in this process. IL-18 binding protein (IL-18BP) forms high affinity complexes with IL-18, thus blocking its interaction with IL-18 receptors.
Methods
We used high-fat diet (HFD) and methionine choline deficient (MCD) diet to model MASLD/MASH in wild-type (WT) male mice (n = 6-8 mice per group). We also studied antimicrobial peptides (AMPs) production, gut microbiota composition and liver phenotype in Il18bp-/- male mice on both HFD and MCD diets (5-7 mice per group). We manipulated gut microbiota of Il18bp-/- and WT male mice through administration of phages, antibiotic and through co-housing experiments (n = 4-8 mice per group).
Results
Feeding WT mice with a HFD or a MCD diet led to a decrease in ileal AMPs expressions (respectively by 63 and 37% for Lyz1; by 47 and 84% for Ang4; by 86 and 46% for Pla2g2a) and an enrichment in gut proteobacteria (respectively by 7 and 23 fold for α-proteobacteria; by 2.1 and 1.7 fold for δ-proteobacteria; by 14 and 20 fold for γ-proteobacteria) when compared to standard chow diet (p<0.05). These changes were associated with a reduction in the ileal Il18bp expression (respectively by 77 and 46%) in HFD and MCD diet-fed WT mice vs. chow diet-fed WT mice (p<0.05). Il18bp-/- mice exhibited a decrease in gut AMPs expression and storage (AMP granules area/crypt respectively decreased by 57 and 62.5% in Il18bp-/- vs. WT mice on HFD and MCD diets). Moreover, Clostridium/Turicimonas/Escherichia bacteria were constitutively overrepresented in gut microbiota of Il18bp-/- vs. WT mice in a diet-amplified manner. Compared to WT mice, Il18bp-/- mice exhibited increased diet-induced hepatic damage (circulating ALT 84 vs. 41 U/L on HFD; 1218 vs. 738 U/L on MCD diet, p <0.05), inflammation (liver TNF-α content 72 vs. 35 pg/g protein on HFD; 441 vs. 169 pg/g protein on MCD diet, p <0.05), and fibrosis (Sirius red 1.45 vs. 0.36% on HFD; 1.64 vs. 0.65% on MCD diet, p <0.01). These changes occurred independently of steatosis modification. Phages, antibiotic and co-housing experiments revealed that specific gut microbiota featuring Il18bp-/- mice is implicated in their exacerbated liver inflammation and fibrosis status.
Conclusions
IL-18BP limits the progression of MASLD/MASH by maintaining a normal intestinal production of AMPs and composition of the gut microbiota.
Impact and implications
Increasing IL-18BP levels represents a novel therapeutic perspective for patients suffering from MASLD/MASH and gut microbiota dysbiosis.TRUEsciescopu
All-optical in vivo photoacoustic tomography by adaptive multilayer acoustic backpropagation
No full textPhotoacoustic tomography (PAT) combines high optical contrast with deep acoustic penetration, making it valuable for biomedical imaging. However, all-optical systems often face challenges in measuring the acoustic wave-induced displacements on rough and dynamic tissues surfaces. We present an all-optical PAT system enabling fast and high-resolution volumetric imaging in vivo. By integrating holographic microscopy with a soft cover layer and coherent averaging, the system detects ultrasound-induced surface displacements over a 10 × 10 mm² area with 0.5 nm sensitivity in 1 s. A novel backpropagation algorithm reconstructs a depth-selective pressure image from two consecutive displacement maps. The coherent summation of these depth-selective pressure images enables the reconstruction of a 3D acoustic pressure image. Using adaptive multilayer backpropagation, we achieve imaging depths of up to 5 mm, with lateral and axial resolutions of 158 µm and 92 µm, respectively, demonstrated through in vivo imaging of mouse vasculature and chicken embryo vessels. © 2025 Elsevier B.V., All rights reserved.TRUEsciescopu
Study on the Role of CX3CR1⁺ Macrophages in Regulating Stem Cell Plasticity during Pulmonary Fibrosis
No full textChronic lung fibrosis involves sustained tissue remodeling and impaired epithelial regeneration, yet the immune mechanisms governing fibrotic niche dynamics remain poorly understood. In this study, we identify CX3CR1⁺ interstitial macrophages—monocyte-derived immune cells—as key modulators of the epithelial stem cell niche during chronic lung injury. Utilizing lineage tracing and APEX-based proximity labeling in murine models, we demonstrate that CX3CR1⁺ macrophages accumulate within fibrotic regions and form close spatial interactions with Krt8⁺ damage-associated transient progenitors (DATPs), other immune cells, and myofibroblasts. Unlike the transient recruitment observed in acute injury, chronic injury promotes their prolonged retention and spatial reorganization, potentially contributing to a stalled regenerative state. These findings position CX3CR1⁺ interstitial macrophages as spatially coordinated regulators of epithelial stem cell regeneration and highlight their potential as therapeutic targets in chronic pulmonary fibrosis.MasterA B S T R A C T ⅰ
C O N T E N T S ⅱ
L I S T O F F I G U R E S ⅳ
Ⅰ . I N T R O D U C T I O N 1
Ⅱ . M A T E R I A L S A N D M E T H O D S 4
1. Mice
2. Bleomycin Administration
3. Lung Tissue Dissociation and Flow Cytometry
4. Lung Tissue Collection
5. Histology and Immunohistochemistry
6. Ex Vivo Labeling of Mouse Tissues
7. Ashcroft score
8. Quantification and Statistical Analysis
Ⅲ . R E S U L T S 9
1. Macrophage accumulation during fibrosis correlates with stem cell and fibroblast niche remodeling
2. Macrophage–stem cell interactions regulate alveolar stem cell plasticity during lung fibrosis
3. Interstitial Macrophage Heterogeneity and Fate Are Dynamically Shaped by Lung Injury Severity
4. Using APEX-mediated proximity labeling, CX3CR1⁺ macrophages were found to dynamically interact with epithelial and immune cells in fibrotic lungs
5. Lung-specific fibrotic injury elicits systemic macrophage interactions in the spleen
Ⅳ . D I S C U S S I O N 4 1
Ⅴ . 국 문 초 록 4 4
Ⅵ . R E F E R E N C E S 4 5
Ⅶ . A C K N O W L E D G E M E N T 4
Development of a Rabbit-Scale Amplitude-Modulated Single-Sided MPI With Flattened FFL Trajectory-Based Reconstruction
No full textMagnetic particle imaging (MPI) is progressing toward clinical applications. These applications demand a large, unobstructed field of view (FOV) and high temporal resolution, making single-sided MPI a promising solution. In this configuration, all hardware components are placed on one side, allowing for a large imaging volume for interventional procedures and accommodating patients or devices of various sizes and shapes. However, conventional field-free line (FFL) single-sided MPI poses challenges in flattening the FFL trajectory, limiting FOV size, and reducing temporal resolution for 3-D image reconstruction in nonuniform magnetic fields. In this article, an amplitude modulation (AM) reconstruction method was applied with separate drive and excitation coils to effectively flatten the FFL trajectory in the horizontal plane for a single-sided MPI configuration. The system was optimized to achieve a larger FOV depth, reduced power consumption, and minimized nonuniform magnetic field along the FFL. As a result, we developed an AM single-sided MPI system with a threefold increase in FOV (40 × 40 × 30 mm3) with significantly enhanced temporal resolution of 2 s per average projection compared to existing conventional single-sided MPI. Moreover, 3-D image reconstruction using an electrically controlled flattened FFL at variable heights up to 30 mm achieved higher temporal resolution (225 s per 3-D image), reduced artifacts, and improved spatial resolution. The system demonstrated a 1-D sensitivity of 60 μgFe and phantom separation capability of 2 mm. We successfully designed, developed, and validated a rabbit-scale AM single-sided MPI with a flattened FFL trajectory, addressing the challenges in the existing conventional FFL-based single-sided MPI toward biological applications. These advancements establish the AM single-sided MPI as a promising solution for imaging near-surface structures in rabbit-scale applications, such as sentinel lymph node biopsy for breast cancer, and lay the groundwork for future human-scale single-sided MPI systems design. © 1963-2012 IEEE.FALSEsciescopu
A Recombinase Polymerase Amplification-LFA Paper Chip for the Naked-Eye Detection of SARS-CoV-2
No full textThe COVID-19 pandemic has exhibited high transmissibility even in asymptomatic individuals, resulting in significant global consequences. The COVID-19 has emphasized the critical need for rapid and accurate detection, particularly during the early stages of infectious disease. The World Health Organization (WHO)-recommended real-time polymerase chain reaction (RT-PCR) provides high sensitivity but requires specialized equipment, trained technician, and consumes a long time for processing, which limit its practicality for widespread use. In contrast, rapid antigen tests offer ease of use but are limited by relatively low sensitivity. To overcome these limitations, this study proposes a novel diagnostic platform that combines the high sensitivity of RT-PCR with the speed and convenience of lateral flow immunoassay (LFA). In this study, we developed point-of-care testing (POCT) device based on isothermal amplification for the detection of SARS-CoV-2. The platform combines recombinase polymerase amplification (RPA), an isothermal amplification method that eliminates the need for thermal cycling equipment, with lateral flow immunoassay (LFA) to enable visual detection of amplification results. The entire diagnostic process, including amplification (~20 minutes) and detection (~10 minutes), is completed within 30 minutes. Additionally, the platform is designed with a single sample inlet for simple and user-friendly operation, making it highly suitable for POCT applications. The platform successfully detected purified SARS-CoV-2 RNA at concentrations as low as 10 copies. Amplification and detection processes were fully integrated into a single platform, and recombinase polymerase amplification (RPA) amplicons visually detected using LFA through simple temperature modulation. This platform as the potential for sensitive and rapid detection of not only SARS-CoV-2 RNA but also a wide range of target RNAs and DNAs, emphasizing its flexibility and suitability as a robust tool for POCT.MasterAbstract
List of contents
List of tables
List of figures
I. INTRODUCTION
1. 1. COVID-19 Caused by SARS-CoV-2 Infection
1. 2. Diagnostic Methods for SARS-CoV-2: Molecular Diagnostics and Immunodiagnostics
1. 3. Lateral Flow Immunoassay (LFA) and Point-of-Care Testing (POCT)
1. 4. Utilizing Isothermal Amplification as a Strategy for Adapting Molecular Diagnostics to POCT
1. 5. Point-of-Care Testing Platform: Rapid and Highly Sensitive Analysis for SARS-CoV-2 Detection
II. Experimental section
2. 1. Materials
2. 2. Preparation of RPA (Recombinase Polymerase Amplification)
2. 3. Gel Electrophoresis
2. 4. Conjugation of Antibodies to AuNPs
2. 5. Fabrication of strip in disposable cartridge
2. 6. A plastic compact heater case
2. 7. Design of the Carbon Circuit
2. 8. Immobilization of Streptavidin and Antibodies on Nitrocellulose Membrane
2. 9. Fabrication of Blended Paraffin Wax and Wax-Coated Wipes
2. 10. Dipstick Assay for Colorimetric Detection
2. 11. Measurement of Heater Setting Temperature and Actual Solution Temperature Using an Infrared Camera
2. 12. Measurement of Carbon Heater Thickness, Resistance, and Temperature
2. 13. Operation of the RPA-LFA One-Hole Kit
III. Result & discussion
3. 1. Schematic representation of the one-hole kit platform
3. 2. Structure and principle of disposable cartridges
3. 3. Paraffin Wax blending
3. 4. Detection of RPA Products Using Antibody-Conjugated AuNPs in LFA
3. 5. Optimization of RPA Reaction Temperature
3. 6. Evaluation of the Performance of the Fabricated Carbon Heater
3. 7. Carbon Heater System: Circuit Configuration and Temperature Switching Mechanism
3. 8. Detection of SARS-CoV-2 RNA via RT-RPA and Lateral Flow Assay (LFA) on the Developed
Platform
IV. Summary
V. Reference
Variable Silicon Isotope Fractionation Between Authigenic Phases and Pore Fluids in Marine Sediments
No full textFormation and subsequent burial of authigenic phases have been recognized as a key process removing silicon from the ocean. However, the effect of authigenic phase formation on the isotopic mass balance of silicon in the ocean is not clear. Here, we constrain the apparent silicon isotope (delta Si-30) fractionation associated with early diagenesis by measuring delta Si-30 signatures of pore fluids and authigenic phases in a South Atlantic sediment core. The delta Si-30 offsets between authigenic phases and pore fluids vary between -2.9 and -0.4 parts per thousand, supporting a substantial negative delta Si-30 fractionation during early diagenesis. The variable apparent delta Si-30 fractionation covaries with the amount of sedimentary lithogenic materials and may be attributable to the associated kinetic effects. Overall, our data show that authigenic phases buried along with their precursor phases preferentially remove isotopically light silicon from the ocean, with implications for the isotopic mass balance of the marine silicon cycle.FALSEsciescopu