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Electrochemical Divergent Synthesis of Azetidines via Strain Release of 1‑Azabicyclo[1.1.0]butanes
ABSTRACT Due to the favorable pharmaceutical properties of the azetidine ring, it can serve as a bioisostere to replace saturated heterocycles such as piperazines, piperidines, and pyrrolidines in drug discovery. The diverse methods for azetidine synthesis are still limited and challenging. Herein, we design a new class of 1‐azabicyclo[1.1.0]butanes (ABBs) and report the first electrochemical protocol for the synthesis of chemo‐selective trifluoromethanesulfonylated and trifluoromethylated azetidine derivatives via direct anodic oxidation. The key features of this strategy involve: (i) electrochemical anodic oxidation of ABB to form a N ‐centered radical cation, (ii) a rare [2,3]‐sigmatropic shift of sulfone, (iii) selective oxidation of Langlois’ reagent (NaSO 2 CF 3 ), and (iv) the kinetic study of the developed methodology. The strategy exhibits broad substrate scope and scalability, making it practical. Installation of generated azetidines into marketed drug motifs, including ibuprofen, naproxen, and olaparib derivative, demonstrates the method's utility. Mechanistic investigations, supported by control experiments, cyclic voltammetry, and electrochemical impedance spectroscopy (EIS), provided key insights into the reaction pathway. This electrochemical approach advances the strain‐release chemistry of ABBs and offers a promising platform for future developments.
A data-driven framework for assessing structural heterogeneity and nonlinear performance in university sports governance
An ubiquitous antibacterial toxin from human gut bacteria engenders neonatal colonization advantage
Harnessing Point–Planar Chirality Synergy: Crystallization‐Enabled Resolution of Pillar[5]arene Rotaxanes With Tunable Circularly Polarized Luminescence
ABSTRACT Immobilizing the planar chirality inherent to pillar[5]arene remains a challenge in supramolecular chemistry. Herein, we report a rational strategy for constructing chiral pillar[5]arene‐based [2]rotaxanes and controlling their planar chirality by incorporating sterically bulky chiral stopper groups at both ends of the axle units. Using this approach, six structurally distinct [2]rotaxanes were efficiently resolved via simple recrystallization, achieving yields exceeding 90% and diastereomeric ratios ( d.r .) above 99.5:0.5. These molecules can be classified as either synergistic or mismatched point–planar chiral [2]rotaxanes. Remarkably, only the synergistic point–planar chiral [2]rotaxanes exhibited tunable circularly polarized luminescence (CPL), with a maximum | g lum | value of 0.02, whereas the mismatched configurations yielded no detectable CPL signal. This work overcomes a fundamental bottleneck in the scalable, stereocontrolled synthesis of chiral pillar[5]arene rotaxanes and establishes a robust platform for their development in chiroptical materials.
Constructing a prognostic survival model for patients with stage II-IV epithelial ovarian cancer: a study based on the SEER database and external validation in China
Overprinting with tomographic volumetric additive manufacturing
Damage mechanisms in St. Bartholomeus Church under gravity, snow, and seismic loads
Polarization reversal and ion-electron co-modulation in in-plane anisotropic AgVP2S6 for multimodal image processing
Subporphyrin Frameworks: A Missing Link Between Porphyrinoids and Porous Aromatic Networks
ABSTRACT Subporphyrins represent a distinctive class of bowl‐shaped, π‐conjugated, and intrinsically electron‐deficient macrocycles that exhibit photophysical and coordination behaviors unlike those of planar porphyrins. While current studies have primarily focused on the synthesis of subporphyrins with an increased number of aromatic rings and complex heterostructures, research on polymeric subporphyrin materials has not yet been reported. Herein, we report the first subporphyrin‐based porous aromatic networks (PAF‐HNU1 and PAF‐HNU2) synthesized by coupling meso‐functionalized subporphyrins with rigid aromatic linkers under solvothermal conditions. The frameworks exhibit extended π‐delocalization and strong red‐shifted absorption covering the UV–vis‐NIR region, enabling efficient full‐spectrum light harvesting. It was discovered that PAF‐HNU2 exhibited high photogenerated charge separation and transport capabilities, as well as outstanding catalytic efficiency for a series of advanced oxidation reactions. Performance was two to three times that of PAF‐HNU1 and its porphyrin‐based PAF analogues. This work introduces a new family of subporphyrinic porous materials, providing the missing link between porphyrinoid chemistry and extended π‐conjugated frameworks, and highlights their potential as a metal‐free platform for next generation full‐spectrum photocatalytic transformations.
Sensor fusion and downscaled climate projections reveal climate refugia in the California Channel Islands
Abstract Conservation actions such as habitat restoration and translocation require spatially informed, quantitative decision-making. We modeled habitat suitability for nine priority landbird species of the Channel Islands to understand habitat preferences, inform conservation planning and assess future climate impacts. In the absence of recent airborne lidar, we derived vegetation structure from spaceborne lidar, radar and optical remote sensing data combined with downscaled climate observations to train machine-learning models. Models performed well (average AUC = 0.84) under spatial cross-validation. Incorporating citizen science data improved Boyce Index performance for eight of the nine species, though AUC declined for 6 out of 9 species, likely reflecting spatial bias in opportunistic records. A radar-derived vegetation index was consistently influential, while maximum temperature strongly affected species restricted to Santa Cruz Island. Most species are projected to lose suitable habitat under two near-future (2040–2069) climate scenarios, except Grasshopper sparrow, Island scrub jay and Rufous-crowned sparrow. We identified climate change refugia to inform spatial conservation priorities.
A disease-centric vision-language foundation model for precision oncology in kidney cancer
Green‐Emissive Ferroelectric Optical Thermometer Based on Cyclometalated Dicyanidoplatinate(II) Ions
ABSTRACT Multifunctional ferroelectrics combine switchable permanent polarization with other physical functionalities. Among them, luminescent ferroelectrics are coming into the spotlight due to their potential in sensing, data storage, and optoelectronics. This multifunctionality can be improved if their emission is sensitive to external stimuli, such as temperature ( T ), which is utilized in optical thermometry. Aiming at ferroelectric luminescent thermometers, we decided to explore photoluminescent cyanido metal complexes. We report a hybrid salt of strongly emissive dicyanido(2‐phenylpyridinato)platinate(II) complexes and N‐methyl‐quinuclidinium cations, (Meabco)[Pt II (CN) 2 (ppy)] ( 1 ). It crystallizes in a polar I ma2 space group, as confirmed by the second harmonic generation activity reaching 44% of the KDP reference. Piezoresponse force microscopy (PFM) studies indicate ferroelectricity at room temperature (RT). Due to [Pt II (CN) 2 (ppy)] – complexes, 1 shows T ‐dependent charge‐transfer photoluminescence (PL), which was applied for ratiometric optical thermometry that was proven experimentally and through TD‐DFT calculations. Its best performance is located at cryogenic temperatures, but optical thermometry is preserved in the around‐RT region with a convenient linear response of the thermometric parameter to the T variation. This electro‐optical multifunctionality was demonstrated for a crystalline sample. However, we prove the processability of 1 into a thin film of several nanometers in thickness, opening the applications‐oriented exploration of related materials.
Enhancing life jacket detection for maritime search and rescue using YOLO models and illumination-robust preprocessing techniques
Abstract Maritime Search and Rescue (SAR) operations are often challenged by vast search zones, poor visibility, and extreme lighting conditions, especially during nighttime missions. This study investigates the use of computer vision and object detection algorithms to automate life jacket detection and improve SAR effectiveness. To address the absence of domain-specific datasets, a custom image dataset featuring multiple life jacket types was developed. A two-fold methodology was adopted: evaluating the performance of YOLO object detection models (versions 5 through 12) on the dataset, and incorporating advanced image preprocessing techniques to enhance detection under challenging lighting conditions. The results demonstrate that preprocessing significantly improves detection performance in both overexposed and underexposed scenarios. Among all evaluated models, YOLOv10 achieved the strongest combination of precision and real-time inference speed (43.9 FPS on Tesla T4 GPU), making it a promising candidate for time-sensitive rescue applications. While individual cells of Tables 5, 6, 7, 8 and 9 show other detectors achieving higher precision under specific lighting × preprocessing combinations, YOLOv10 offers the best aggregate trade-off across the evaluated criteria. This work contributes a scalable benchmark solution for improving SAR outcomes by enabling faster and more reliable identification of individuals in distress at sea.
Mycobacterium tuberculosis IDH-PPARγ interaction suppresses GPX4 to drive macrophage ferroptosis and sustain persistent infection
Constructing Robust Cl‐Bridge for Ultrafast Leaching of Spent Cathodes in 180 s
ABSTRACT Reductive coordination medium, especially Cl − , play a pivotal role in leaching processes for spent batteries recycling. However, poor mass transfer and limited reducibility of the reactive species often lead to sluggish leaching kinetics of critical metals. Herein, we propose a strategy to construct a robust chloride bridge that enhances the enrichment and reactivity of Cl − at the solid–liquid reaction interface. Based on this, the developed recycling system with a Cl‐SO 3 H bridge achieves complete leaching of Li, Ni, Co, and Mn within just 180 s. Specifically, the sulfur atom in the sulfonic acid group exhibits a high electron‐donating ability, which enhances the nucleophilicity and reducing capacity of Cl − within this bridge. This facilitates rapid migration and coordination of Cl − with metal ions on the spent cathode surface, accelerating the cleavage of metal─oxygen bonds. Furthermore, a closed‐loop recycling route based on solvent regeneration and reuse was designed in this work. Compared with conventional hydrometallurgical processes, this system improves the overall economic efficiency of spent battery recycling by nearly fourfold while halving carbon emissions.
Investigation of the guaiazulene–p-chloranil charge transfer complex in solution: a combined spectroscopic and quantum chemical approach
Interspecies quorum sensing signals modulate multicellular organization and enhance contact-dependent antagonism in Vibrio cholerae
Abstract Spatial organization within bacterial communities plays a critical role in mediating cell-cell interactions and determining microbial fitness. During infection, Vibrio cholerae undergoes dynamic restructuring of its spatial organization, forming monospecific aggregates thought to enhance survival in the face of the host immune system. However, the effectiveness of its primary weapon against other bacteria—its contact-dependent type VI secretion system (T6SS)—is severely limited in this aggregated form, hampering its ability to compete for space and resources. Here, we show that the presence of competing, co-resident bacteria alters V. cholerae aggregation by modulating toxin co-regulated pilus (TCP) expression through production of interspecies quorum sensing signal autoinducer-2 (AI-2). Using a zebrafish infection model, we found that this quorum sensing-controlled disaggregation enhances the efficacy of T6SS-mediated killing in vivo by promoting intermixing of V. cholerae , thereby increasing cell-cell contact with competitors. This modulation of aggregation has no impact on T6SS activity in vitro, highlighting the context-specific nature of these interactions. We developed a mathematical model to explore these dynamics and observed a fundamental trade-off between potency of V. cholerae T6SS and its sensitivity to the presence of competing bacterial species. Our findings reveal a core mechanism underlying V. cholerae colonization wherein it uses quorum sensing to dynamically balance between protective aggregation to survive host defenses and dispersed infiltrative intermixing to facilitate elimination of competitors.
NaO <sub>6</sub> Octahedron‐Engineered Sodium Iron Sulfate Cathodes for High‐Rate and Sustainable Sodium‐Ion Batteries
ABSTRACT The alluaudite‐type sulfate Na 2 Fe 2 (SO 4 ) 3 (NFS) has attracted considerable interest as the cathodes for sodium‐ion batteries (SIBs) due to its low cost and high operating voltage. However, it is plagued by sluggish Na + transport kinetics and irreversible lattice distortion arising from Fe 3+ migration. Herein, NaO 6 units have been incorporating into NFS to form a sodium‐rich site‐type sodium iron sulfate (Na 6.4 [Fe 5.5 Na 0.6 ](SO 4 ) 9 ), in which Na + substitution at Fe sites induces intrinsic Na + occupation of structurally unstable Fe sites, effectively suppressing Fe migration. Meanwhile, the enlarged Fe–Fe spacing within [Fe 2 O 10 ] dimers mitigates repulsion‐driven Fe migration, synergistically enhancing lattice stability. Furthermore, enhanced oxygen ionicity in NaO 6 units elongates the rate‐determining Na─O bond, thus enhancing the Na + migration kinetics. As a result, the Na 6.4 [Fe 5.5 Na 0.6 ](SO 4 ) 9 cathode achieves an impressive rate performance (100.2 and 75.2 mA h g −1 at 0.1 and 20C, respectively), with 98.2% capacity retention after 2000 cycles at 20 C. Moreover, the corresponding pouch cells stably operate for 500 cycles with 80.9% capacity retention. Rather than simply increasing Na occupancy at pre‐existing Na sites, this sodium‐rich site strategy introduces new Na sites at specific lattice positions, providing a viable design paradigm for advancing low‐cost polyanionic Na‐storage materials.