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Experimental and analytical investigation of flow boiling maldistribution in parallel mini/micro-channel heat sinks under non-uniform heating conditions
No full textThis study elucidates the mechanism of flow boiling maldistribution in parallel mini/micro-channel heat sinks under non-uniform heat flux conditions, with particular emphasis on key instability phenomena. The relative dominance of forward and backward forces in individual channels critically influences the intensity of flow maldistribution, and a modified instability parameter, R *, was introduced to quantify this dominance. A strong correlation is established between R * and the degree of flow non-uniformity, with the most severe maldistribution observed near R * ≈ 1.58. The analysis reveals that flow resistance in individual channels—governed by both thermal and hydrodynamic factors—is the dominant factor affecting flow distribution. Unlike single-phase flow, where resistance depends solely on hydrodynamics, two-phase flow boiling is highly sensitive to heat flux, inlet subcooling, and vapor backflow. The study further identifies a coupling mechanism between pressure-coupled instability (PCI) and vapor backflow, where vapor propagation into the inlet plenum elevates the local temperature, alters the flow inertia, and reshapes the distribution among channels. These findings highlight the critical role of thermal characteristics in the inlet plenum and the importance of dynamic instabilities and thermal non-equilibrium in predicting and controlling flow maldistribution in high-heat-flux thermal management systems. © 2025 Elsevier Ltd.FALSEsciescopu
Single-Nucleus Multi-Omics Reveals Hypoxia-Driven Angiogenic Programs and Their Epigenetic Control in Sinonasal Squamous Cell Carcinoma
No full textSinonasal squamous cell carcinoma (SNSCC) is a rare malignancy with poorly understood molecular drivers. Consequently, its cellular composition and tumor microenvironment (TME) remain largely undefined. Here, we performed integrated bulk and single-nucleus multi-omic analyses to map the SNSCC ecosystem. Within the malignant compartment, we identified five distinct populations, with hypoxic (TC1) and proliferative (TC2) subtypes associated with adverse clinical outcomes. Functionally, TC1 cells orchestrate a hypoxia-driven angiogenic program via coordinated secretion of adrenomedullin (ADM), MIF, and VEGFA, promoting endothelial tip cell (EC1) differentiation. Integrative analysis revealed these transcriptional programs are underpinned by tumor-specific chromatin accessibility and DNA hypomethylation, particularly at AP-1-enriched regulatory elements. Mechanistically, in vitro studies confirmed that this response depends on cooperative AP-1 and HIF1A signaling. Furthermore, histological analysis of patient tissues demonstrated spatial co-localization of GLUT1-expressing TC1 cells with DLL4-positive EC1 cells. These findings elucidate the epigenetic landscape underlying tumor-stromal interactions and establish the ADM/VEGFA axis as a critical therapeutic target to disrupt epigenetically controlled angiogenesis in SNSCC.TRUEsciescopu
What and when to look? Temporal span proposal network for video relation detection
No full textIdentifying relations between objects is central to understanding the scene. While several works have been proposed for relation modeling in the image domain, there have been many constraints in the video domain due to challenging dynamics of spatio-temporal interactions (e.g., between which objects are there an interaction? when do relations start and end?). To date, two representative methods have been proposed to tackle Video Visual Relation Detection (VidVRD): segment-based and window-based. The segment-based methods lack temporal continuity on the other hand, window-based scale poorly. To tackle this limitations of typical methods, we propose a novel approach named Temporal Span Proposal Network (TSPN). TSPN tells what to look: it sparsifies relation search space by scoring relationness of object pair, i.e., measuring how probable a relation exist. TSPN tells when to look: it simultaneously predicts start-end timestamps (i.e., temporal spans) and categories of the all possible relations by utilizing full video context. These two designs enable a win-win scenario: it accelerates training by 2X or more than existing methods and achieves competitive performance on two VidVRD benchmarks (ImageNet-VidVRD and VidOR). Moreover, comprehensive ablative experiments demonstrate the effectiveness of our approach.FALSEsciescopu
Rational design of isatin-based quinoidal conjugated polymers for efficient organic photovoltaics with dual donor ternary strategy
No full textThe quinoid strategy is regarded as a promising approach for fabricating high-performance organic semiconductor materials. However, the applications of quinoidal conjugated polymers (QCPs) are mostly limited to organic field-effect transistors (OFETs), and their photovoltaic applications remain challenging. In this study, two novel QCPs, PQ-H and PQ-F, were designed and synthesized by incorporating isomer-free deep-energy-level quinoid units. Using them as third components, ternary organic photovoltaic (OPV) devices combining the polymer donor PM6 and small-molecule acceptor Y6 were fabricated in an inverted configuration. The complementary absorption behavior of the QCPs with PM6 and Y6 enhanced light harvesting. In particular, owing to the achievement of an ideal morphology by introducing QCPs, the fill factor (FF) and open-circuit voltage (VOC) of the ternary OPVs were improved. Consequently, by incorporating 1 wt% PQ-H and 2 wt% PQ-F in the ternary films, higher average power conversion efficiencies (PCE) of 14.16 % and 14.54 %, respectively, were recorded compared to that of PM6:Y6 binary OPVs (13.63 %). This study demonstrates that with a suitable molecular design approach, QCPs can act as photoactive materials and their small amounts can significantly affect the performance of ternary OPVs to enhance all photovoltaic parameters. © 2026FALSEsciescopu
Early Detection of Mild Cognitive Impairment Through Balance Assessment Using Multi-Location Wearable Inertial Sensors
No full textEarly detection of Mild Cognitive Impairment (MCI), a prodromal stage of dementia, plays a pivotal role in enabling timely clinical intervention and slowing cognitive decline. This paper presents a multi-sensor balance assessment framework designed to identify MCI-related postural instabilities using a wearable inertial measurement unit (IMU) network. The proposed system employs five synchronized IMUs placed at the waist, thighs, and shanks to capture balance dynamics across four static balance tasks: Eyes-Open, Eyes-Closed, Right-Leg Lift, and Left-Leg Lift. A three-stage feature selection strategy, comprising variance and correlation pruning, univariate filtering, and embedded model selection, is implemented within a Leave-One-Subject-Out (LOSO) cross-validation scheme to extract discriminative sway features. Classification using Support Vector Machines and tree-based ensemble models consistently yields superior results, achieving accuracies between 71.7% and 79.2%, with the highest performance observed in the Eyes-Open condition. A compact 10-feature subset demonstrates stable and robust discriminative power across all tasks. Compared to a single-sensor baseline, the multi-sensor configuration provides improved classification performance, underscoring the feasibility of compact, balance-driven, non-invasive MCI screening through wearable sensor systems.TRUEsciescopu
Recent advances in COF-based separators for rechargeable batteries: Design, properties, and applications
No full textResearch into novel materials for rechargeable batteries has increased due to the growing need for long-lasting, high-performance energy storage solutions. One of the most important components is the separator, which ensures the safe and quick passage of ions while maintaining system stability. Covalent organic frameworks (COFs) are porous crystalline polymers that exhibit remarkable chemical stability and a variety of topologies. Their applications as components for next-generation battery separators have grown. This study examines current advances in the design, fabrication, and application of COF-based separators in a variety of rechargeable battery systems, including lithium-ion, lithium‑sulfur, sodium‑sulfur, zinc‑sulfur, and zinc‑iodine batteries. We explore into the way COFs' distinct structural properties, such as structured nanochannels, variable functional groups, and high porosity, can improve ion selectivity, electrolyte wettability, and prevent dendritic and polysulphide movement. We also discuss the relationship between structure and property, synthesis methods, and critical performance criteria, with an emphasis on recent developments in COF membrane design. The study concluded by outlining the present problems and offering suggestions for the future development of scalable, highly effective COF-based separators for the upcoming generation of energy storage devices. © 2025 Elsevier LtdFALSEsciescopu
Local fields reveal atomic-scale nonadiabatic carrier-phonon dynamics
No full textUnderstanding nonadiabatic carrier-lattice interactions at the atomic scale remains a fundamental challenge, yet these processes govern energy transfer in materials and ultimately set limits in microelectronics. We combined attosecond core-level transient absorption spectroscopy with many-body theory to uncover how nonadiabatic electron-phonon coupling drives ultrafast relaxations in a titanium-carbide MXene. Phonon-driven changes in carrier localization modulated local field effects (LFEs), yielding carrier-, site-, and orbital-specific absorption signatures. LFEs served as sensitive fingerprints of electron-phonon coupling strength across the phonon spectrum and revealed a breakdown of the Born–Oppenheimer approximation: Electrons lagged lattice oscillations by 32 ± 8 femtoseconds, whereas holes responded almost instantaneously (7 ± 7 femtoseconds). Our results establish a framework for probing and controlling nonadiabatic carrier-phonon interactions with orbital and site specificity.FALSEsciescopu
Bleeding flow characteristics downstream of isotropic porous square cylinders
No full textThis study experimentally investigates the bleeding flow characteristics downstream of isotropic porous square cylinders as a function of permeability and pore configuration across a broad range of Darcy numbers ( ). The porous cylinders, constructed with a simple cubic lattice design, were fabricated using a high-resolution three-dimensional printing technique. This novel design method, based on a periodic and scalable lattice structure, allows fine control over the number of lattice pores along the cylinder width, , and the corresponding permeability, independently of porosity. Permeability was carefully determined by measuring the pressure drop and superficial velocity for each porous structure considered in this study. High-resolution particle image velocimetry measurements were conducted in an open-loop wind tunnel to characterize the downstream flow structures. The results reveal that bleeding flow characteristics near the cylinder trailing edge are strongly influenced by both permeability and pore configuration. These structural behaviours are further explored using an analogy to multiple plane turbulent jets. This approach identifies three distinct flow regions downstream of porous square cylinders, determined by the structural pattern of the bleeding flow. Additionally, an analytical framework is developed to model the longitudinal extent of the merging region by integrating the momentum equation, incorporating the Darcy-Brinkman-Forchheimer model, with a boundary layer assumption. The analytical model is validated against experimental data, demonstrating its capability to predict the key dynamics of bleeding flow evolution. Our results provide new insights into the fluid dynamics of porous bluff bodies, establishing pore configuration and permeability as dominant parameters governing downstream flow structures.TRUEsciescopu
Unconventional monooxygenation by the O2-dependent tRNA wobble uridine hydroxylase TrhO
No full textModifications at the wobble position of transfer RNA (tRNA) are critical for accurate codon recognition and efficient translation. 5-Hydroxyuridine serves as a key intermediate for more complex wobble uridine derivatives commonly found in bacterial tRNAs and is synthesized by either prephenate-dependent TrhP or dioxygen-dependent TrhO. Despite its biological importance, structural and mechanistic insights into these enzymes have remained elusive. Here, we report the cryo-electron microscopy structure of Bacillussubtilis TrhO-tRNAAla complex. Combined with biochemical analyses, our results reveal that TrhO functions without any metal or organic cofactor, unlike most other oxygenases. We propose that the conserved C179 reacts with dioxygen to form a thiohydroperoxy intermediate, which is cleaved to produce 5-hydroxyuridine and a sulfenic acid at C179. The oxidized cysteine subsequently forms a disulfide bond with the adjacent C185, protecting the catalytic cysteine from irreversible overoxidation. These findings broaden our understanding of cofactor-independent dioxygen use in aromatic ring hydroxylation.FALSEsciescopu
Conditionally Activatable Antibody Platforms: Mechanisms, Modalities, and Clinical Translation Potential
No full textConditionally activatable antibodies represent a promising strategy to improve the therapeutic index of antibody-based drugs by restricting their activity to disease sites, thereby minimizing systemic toxicity. These engineered platforms leverage disease-associated cues—such as protease activity, pH, redox gradients, or other microenvironmental factors—to modulate antigen binding or effector function in a spatially and temporally controlled manner. In this review, we categorize recent advances in activatable antibody technologies into three principal strategies: (1) masking domains or peptides that block target recognition until removed by disease- specific triggers, (2) structural rearrangement by fusing external domains to antibodies to regulate access to the paratope, and (3) payload activation approaches in antibody–drug conjugates. We summarize key design principles, representative examples, and their preclinical or clinical development status, highlighting strengths, limitations, and translational challenges. Special attention is given to linker chemistry, trigger specificity, and pharmacokinetic considerations that influence therapeutic performance. Finally, we discuss emerging trends, including multi-input activation systems and integration with next-generation modalities such as bispecific antibodies and immune cell engagers, which could further refine target selectivity and broaden therapeutic applications. This overview highlights representative advances to guide the rational design of future activatable antibody platforms and to accelerate their progression toward clinical use.FALSEsciescopu