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Alumina-Templated ortho-Prenylation of Phenols
DFT and molecular docking investigation of tamoxifen interactions with metal-encapsulated boron nitride nanocages
Abstract Tamoxifen (TMF), a lipid-soluble selective estrogen receptor modulator (SERM), is extensively used in the treatment of breast cancer. In this work, we systematically investigate the covalent and non-covalent interactions of TMF with the perfect B 12 N 12 compared to as well as with calcium- and potassium-encapsulated derivatives (B 12 CaN 12 and B 12 KN 12 ). These interactions are predominantly mediated by the dimethylamino group (-N(CH₃)₂) of TMF and were examined using density functional theory (DFT) calculations at the M06-2X level, incorporating D3 dispersion corrections (M06-2X-D3) and the 6–31 + G** basis set. The results reveal that TMF undergoes strong chemisorption on B 12 KN 12 (-2.27 eV) and B 12 CaN 12 (-1.91 eV), in contrast to weaker adsorption on the pristine B 12 N 12 surface (-1.75 eV). The strong binding of TMF to B₁₂N₁₂ via its dimethylamino group occurs through a synergistic combination of covalent interactions and hydrogen bonding, accompanied by a larger charge transfer from the drug to the cage, leading to a significant increase in dipole moment and a change in the energy gap. Thermodynamic analyses based on Gibbs free energy and enthalpy changes confirm that complex formation is highly stable, spontaneous, and exothermic. Notably, B 12 N 12 exhibits the shortest recovery time, indicating rapid TMF detachment, whereas B 12 CaN 12 and B 12 KN 12 show longer desorption times, favoring sustained release. ADMET predictions suggest moderate intestinal absorption and good membrane permeability, indicating potential for oral bioavailability. Docking studies reveal that B 12 KN 12 enhances TMF binding to EGFR, HER2, and Caspase-8, despite a minor reduction in ERα affinity, supporting the potential of B 12 KN 12 as a nanocarrier for HER2-driven breast cancer treatment.
Highly scalable, dialysis-controlled synthesis of colloidal molecules via regulated self-assembly of polymer-grafted gold nanoparticles
Electrostatic headroom coordinated minimum feasible high-frequency injection strategy for low-speed motor drives using a half bridge modular multilevel converter
Abstract This paper proposes a boundary-based minimum-injection high-frequency balancing strategy for low-speed standard half-bridge modular multilevel converter (MMC) motor drives to reduce the injected high-frequency balancing voltage and current and the associated electrical stress while maintaining the prescribed submodule capacitor-voltage ripple limit. The proposed method preserves the conventional Korn-type high-frequency injection (HFI) balancing path, but determines the commanded injection level from a constrained minimum-injection condition governed by the residual arm-energy demand and the available electrostatic buffering capability of the capacitor stack. An analytical operating boundary between HFI-assisted balancing and capacitor-based self-buffering is established by comparing the residual-energy requirement with the usable capacitor-voltage headroom constrained by modulation feasibility and the upper submodule voltage limit. Accordingly, the injection coefficient and the average capacitor-voltage reference are jointly coordinated so that the capacitor stack buffers the admissible residual energy, whereas the HFI channel supplies only the remaining balancing component required for ripple regulation. Comparative simulations against fixed HFI and a recent adaptive HFI benchmark demonstrate reductions of 33.0% in the mean compensation coefficient, 29.1% in the representative peak-to-peak submodule capacitor-voltage ripple, 13.7% in the representative arm-current RMS, 28.5% in the representative arm-current peak, and 25.3% in the current-squared loss proxy. The common-mode-voltage benefit is mainly reflected in the RMS and accumulated-burden indices rather than in the reduction of every instantaneous peak. These results verify that the proposed strategy reduces the injected high-frequency balancing content and the associated current- and voltage-side stresses under explicit ripple, modulation, and capacitor-headroom constraints.
Neural dynamics for working memory and evidence integration during olfactory navigation in Drosophila
Occupational sleepiness in suburban metro drivers: association with fatigue, occupational balance and work functioning
Abstract The study examined levels of daytime sleepiness, occupational fatigue, perceived work functioning and occupational balance among suburban metro train drivers, and identified independent predictors of daytime sleepiness. A cross-sectional study was conducted with 191 public transport train drivers who completed validated self-report measures assessing sleep-related functional outcomes (FOSQ), daytime sleepiness (ESS), occupational fatigue (SOFI), work role functioning (WRFQ) and occupational balance (OBQ-E). Descriptive analyses and Pearson correlations were performed, and a multiple linear regression model adjusted for work shift identified independent predictors of daytime sleepiness. Clinically relevant levels of daytime sleepiness (ESS median 11, IQR 7–15) and occupational fatigue were observed. Sleepiness showed a moderate positive correlation with occupational fatigue ( r = .544, p < .001) and negative correlations with occupational balance ( r = − .419, p < .001) and work role functioning ( r = − .434, p < .001). The regression model adjusted for work shift was significant (F(6,173) = 17.00, p < .001) and explained 37.1% of the variance. Occupational fatigue (β = 0.298, p = .002), occupational balance (β = −0.210, p = .007) and work role functioning (β = −0.169, p = .045) were significant predictors of daytime sleepiness, whereas work-shift categories were not significant after adjustment. Interventions targeting fatigue management and occupational balance may help reduce sleepiness and enhance operational safety.
Goblet cells mechanically breach the epithelial barrier in gut homeostasis
Abstract The intestinal epithelium forms a tight barrier against the harsh luminal environment. Absorptive enterocytes have a polygonal, columnar morphology, while mucus-producing goblet cells exhibit a rounded apical shape and a voluminous cell body, raising the question of how epithelial integrity is preserved in tissues with such morphological heterogeneity. Here, we show that, under homeostatic conditions in vivo, goblet cells mechanically induce tight-junction fractures between neighboring enterocytes. This effect is exacerbated by goblet cell hypertrophy and is associated with increased gut permeability. Using in vivo and organoid models, combined with pharmacological, genetic and mechanical perturbations and theoretical modeling, we demonstrate that these fractures arise from a force imbalance at cell interfaces: goblet cells exert pressure on adjacent enterocytes, whose junctional rupture depends on tissue rheology controlled by myosin II. Our findings uncover a mechanical role for goblet cells in epithelial cohesion and barrier regulation, revealing how cellular heterogeneity shapes tissue integrity.
Integrated proteomics–driven discovery of synovial fluid biomarkers reflecting structural damage and pain in knee osteoarthritis
Synergy between reactive manganese species and enzymes drives litter decomposition hotspots
Abstract Oxidative decomposition of plant litter is a central control on carbon storage and productivity in terrestrial ecosystems. Although this process is commonly assumed to be greatest under oxic conditions, recent findings highlight redox-sensitive metals and enzymes as potent, but poorly understood, mediators. Using controlled soil reactors, we show that stimulating microbial production of reactive manganese(III) at oxic–anoxic interfaces simultaneously increased the expression of diverse litter-decomposing enzymes; together, these metal and enzyme catalysts acted synergistically to accelerate litter decomposition. This 29% increase in decomposition was best predicted by multi-fold increases in the expression of putative Mn(III)-forming and litter-degrading enzymes at the interface, rather than by patterns in strictly oxic or anoxic zones. These results provide evidence to the growing body of research challenging the assumption that oxidative decomposition is maximized under fully oxic conditions. Instead, they reveal a tight interplay among oxygen supply, reactive metal regeneration, and enzyme activity that renders oxic–anoxic interfaces hotspots of litter decomposition in soils.
Attentional focus modulates neuromechanical organization and motor complexity during walking
Abstract Attentional focus instructions have long been recognized for their impact on motor performance and learning, yet their influence on the neuromechanical aspects of gait—spanning multiple analytical levels—remains underexplored. In this study, the authors investigated how attentional focus (internal, external, or no focus) and sex affect lower-limb coordination during walking, drawing on a blend of biomechanical and neuromuscular methods. The complexity of kinematic and electromyographic (EMG) signals was quantified using sample entropy, the inter-joint coordination was evaluated through the Uncontrolled Manifold (UCM) framework by calculating the synergy index (ΔV = log₁₀(V_UCM / V_ORT)) in the sagittal, frontal, and transverse planes, and muscle synergies were extracted via non-negative matrix factorization, emphasizing the number needed to account for 90% of the total variance (VAF). The findings highlighted a persistent main effect of attentional focus across all levels. External focus led to greater kinematic and EMG sample entropy, suggesting heightened movement complexity. Likewise, the UCM synergy index (ΔV) was markedly higher with external focus in every plane, indicating more variability that stabilized the task. In muscle synergy analysis, attentional focus reshaped neuromuscular modularity, requiring fewer synergies to achieve 90% VAF under external focus. Sex differences were modest, appearing only in sagittal-plane ΔV, with no interactions between attentional focus and sex. These results illustrate how attentional focus reshapes gait organization from signal complexity to inter-joint coordination and neuromuscular patterns. Together, they bolster the notion that external focus encourages more adaptive, task-oriented control during walking. This underscores the benefits of multilevel analyses in unpacking the mechanisms behind attentional influences on locomotion.
Phase locking and multistability in the topological Kuramoto model on cell complexes
Abstract Higher-order interactions fundamentally shape collective dynamics in oscillator networks. The topological Kuramoto model captures these effects by extending synchronization models to include interactions between cells of arbitrary dimension within simplicial and cell complexes. We introduce the topological nonlinear Kirchhoff conditions to characterize all phase-locked states of the topological Kuramoto model. These states are organized by winding numbers associated with generalized independent cycles, which quantify how phases wind around these cycles. Using rings, Platonic solids, and regular simplices as illustrative examples, we uncover a universal rule: boundaries must have at least five elements for multistability to arise. We further find that independent winding numbers associated with lower- and higher-dimensional boundaries generate cascades of multistability across dimensions. These results show how the topology and boundary structure of cell complexes influence phase locking and multistability, and provide a general framework for collective dynamics on cell complexes.
Deep learning based feature extraction for liver tumour classification using computed tomography images
Observed thresholds in sea-level rise driving global tidal wetland loss
Design and transfection of CRISPR/Cas9 constructs for the myostatin gene in Labeo rohita muscle cells
Finding the perfect promoter for Cas9 in homing gene drives using single cell transcriptome data
Abstract Gene drive can modify or suppress vector populations by spreading drive alleles. In CRISPR homing drives, regulating Cas9 expression has been effective for improving drive performance, but selecting suitable promoters is often a major challenge. Here, we evaluate 35 Cas9 constructs with distinct promoters in Drosophila melanogaster and identify associations between drive performance and single-cell RNA expression patterns of the promoter-associated genes. Our results indicate that higher drive conversion is associated with elevated expression of the promoter-associated gene in reproductive cells, but embryo resistance allele formation correlates with excessive female germline expression. For males, early germline expression produces superior performance. Thus, optimal drive performance requires restricting Cas9 expression to a tight quantitative and spatiotemporal window. Additionally, we find that an in situ construct significantly reduces potentially harmful somatic expression. Based on these results, we propose criteria for selecting promoters, providing a rationale and guidance for optimization of homing gene drives.
Evaluation of soil degradation caused by wildfire through integration of remote sensing soil quality indices and micromorphological analyses
Semiconductor room-temperature maser
Abstract We report the first demonstration of a semiconductor maser based on silicon vacancies (V Si ) in 4H-silicon carbide (SiC). Using an active feedback loop, we enhance the resonator’s quality factor, enabling continuous-wave maser operation even above room temperature. We analyzed the SiC maser as a high-performance preamplifier, with measured gain exceeding 10 dB at 110 K and simulations suggesting potential amplification beyond 30 dB. Leveraging the small zero-field splitting of V Si , the device can also function as an optically pumped microwave photon absorber, reducing the resonator’s mode temperature by 40 K relative to the environment. Additionally, the maser’s ultranarrow linewidth supports highly sensitive magnetometry, achieving a nine-order-of-magnitude improvement in contrast-to-linewidth ratio over electrical and optical detection of magnetic resonance. This results in an estimated magnetic field sensitivity of 20 pT/√Hz at room-temperature based on the relative intensity noise of the excitation laser. These results underscore the potential of SiC to reshape room-temperature maser technologies, and lay the groundwork for future development of compact, electrically driven maser diodes.
Performance enhancement of hybrid shake table via passive load balancing and nonlinear system identification using coupled ODE modelling
Abstract This study aims to identify a suitable passive load-balancing mechanism for a hybrid shake table, which decouples spatial and planar motion for enhanced control. By minimizing reliance on extensive experimental data, the research seeks to improve system stiffness, compensate for heavy payloads, and enhance the overall performance of shake tables. A regression-based nonlinear least-squares (NLS) technique enhanced by the trust-region-reflective (TRR) algorithm is proposed for system identification. A fusion-based approach is adopted, in which experimental data is used to develop a reduced-fidelity state-space model (SSM) of the shake table, while simulation data is used to evaluate passive load-balancing mechanisms. The study solves higher-order coupled ordinary differential equations (ODEs) to estimate stiffness and damping parameters for various configurations. Among the four vertical motion actuator (VMA) assembly configurations, the configuration equipped with a passive hydraulic damper exhibited superior performance. It attained the highest fit percentages (98.01% and 87.66%), the highest coefficient of determination R 2 values (0.9996 and 0.9847), the lowest normalized root mean square error (NRMSE) values (0.0022 and 0.0083), minimal amplitude errors (0.0338 and 0.1350), and the most negligible phase errors (0 and 0.08) for displacement and velocity responses, respectively. Among the passive mechanisms analyzed, a hydraulic damper proved to be the most effective load-balancing mechanism, demonstrating high stiffness, superior damping, and optimal force compensation. This enhancement is attributed to its nonlinear spring and damping characteristics, which enhance stability under heavy loads. This research presents a standardized approach for solving coupled ODEs in dynamic systems. The findings provide a novel framework for improving shake table performance, with potential applications in earthquake simulation, robotics, and industrial motion platforms.