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Nickel‐Catalyzed 1,2‐Arylalkenylation of Unactivated Alkenes Enabled by a Native Hydroxy Group
ABSTRACT Transition‐metal‐catalyzed dicarbofunctionalization of alkenes represents a powerful strategy for building molecular complexity in a single step. Here we report an unprecedented nickel‐catalyzed 1,2‐arylalkenylation of unactivated alkenyl alcohols using alkenyl boronates and aryl iodides. This method uniquely leverages the native hydroxyl group as an intrinsic directing handle, eliminating the need for pre‐installed auxiliaries and streamlining the synthesis of structurally diverse alkenol derivatives. The reaction proceeds under mild conditions with broad functional group tolerance and excellent regioselectivity, enabling efficient construction of valuable building blocks. Mechanistic studies, supported by DFT calculations, reveal a Ni(0)/Ni(I)/Ni(II) catalytic cycle probably involving aryl radical intermediates. By exploiting alcohols as directing groups, this work expands the scope of alkene dicarbofunctionalization and provides a versatile platform for late‐stage functionalization relevant to pharmaceuticals, agrochemicals, and materials development.
Exploring the specific heat capacity of aqueous blends of K2CO3- PZ-MEA in CO2 capture using ANN and RSM models
Precision Switching and Coupled Motion in a [3]Rotaxane Molecular Machine
ABSTRACT We report the synthesis and the characterization of a multicomponent molecular machine based on a [3]rotaxane architecture. The system is composed by two crown ether macrocycles and an axle with three recognition sites for the rings: ammonium (AmH + ), bipyridinium (Bpy 2+ ), and triazolium (Trz + ). The position of the two rings can be precisely controlled via a sequence of chemical and electrochemical inputs: the two rings can be located on neighboring stations, forced on the same station or separated at the opposite extremities of the axle. This complex mechanism is elucidated by a combination of NMR spectroscopy and voltammetric techniques, allowing to characterize the thermodynamics of the reaction network. The investigation shows that each ring is influenced by the presence and position of the other, resulting in a coupled motion, a critical feature for the development of next‐generation molecular machines.
Eel and grouper lyrebird optimizer based fractal deep spiking residual network for breast cancer detection using mammogram images
Covalent Borane‐Thiourea Organocatalyst for Stereoselective Ring‐Opening Polymerization
ABSTRACT While the chemistry of ring‐opening polymerization has advanced significantly to alleviate the escalating plastic waste crisis, highly selective and efficient catalysts to synthesize chemically recyclable, high‐performance polythioesters remain needed. Typical ring‐opening catalysts, however, face an intrinsic stereochemical challenge: unavoidable monomer racemization due to elevated α‐hydrogen acidity, which severely hampers the synthesis of highly tactic crystalline materials and diminishes the performance of the resulting plastics. Here, we report the design and synthesis of a covalent borane‐thiourea organocatalyst for the stereoselective ring‐opening polymerization of enantiopure dithiolactones. Through incorporation of a strongly Lewis acidic 9‐borafluorene moiety, this metal‐free system effectively reduces the basicity of propagating thiolate chain ends while enabling thiourea‐mediated monomer activation, thereby ensuring rapid polymerization with minimal racemization. Consequently, this approach affords polythioesters with near‐perfect isotacticity ( P m = 0.97) and high molecular weights ( M n up to 58.1 kDa). Notably, the resulting stereoregular polymers are tough, semicrystalline materials with properties comparable to commercial polyolefins like low‐density polyethylene, while exhibiting complete chemical recyclability to realize a sustainable cradle‐to‐cradle closed loop. Overall, this covalent borane‐thiourea organocatalyst solves the intrinsic stereochemical challenges in typical ring‐opening polymerizations, providing a powerful strategy to access chemically recyclable and tough thermoplastics from dithiolactones as promising next‐generation sustainable polymers.
Neural signatures of hyper-realistic AI-generated faces: dissociating behavioral indistinguishability from implicit neural evaluation
Pathway Controlled Phase Separation of Minimal Building Blocks Utilizing a Dissociative Chemical Transformation
ABSTRACT Metastable states are utilized by biology to power the construction of large and motile macromolecules and also to realize out‐of‐equilibrium phase separation. Energy transduction from orthogonal and unrelated exergonic reactions drives the contra‐thermodynamic transformation, which acts as the catalyst for the exergonic reaction. Herein, we show that thermodynamically stable building blocks can undergo phase separation when the process is coupled with an exergonic degradation of their thermodynamically activated precursor. The thermodynamically stable products alone are incapable of accessing the droplets. The chemical transformation is critical to achieve pathway‐controlled phase separation, which catalyzes the chemical transformation. The activated precursor undergoes a β‐elimination reaction to produce an aromatic substrate along with trimethylammonium cations, which provide temporal stabilization to the phase‐separated droplets. Droplet formation is not observed with precursors incapable of undergoing the β‐elimination reaction. The generated droplets can imbibe diverse guest molecules, and their transition from droplets to proto‐tissue‐like structures is observed in the presence of porphyrin. Importantly, the kinetically accessed metastable liquid droplets are shown to augment the catalytic potential of hemin, cofactor of natural peroxidase, and accelerate the hydrolase‐peroxidase cascade reaction.
The impact of the COVID-19 pandemic on rabies control and health-seeking behavior for postexposure prophylaxis (PEP) in Serbia and North Macedonia and lessons learnt
Abstract Rabies remains a fatal zoonotic disease of significant public health concern, particularly in regions where surveillance and vaccination campaigns are inconsistent. The COVID-19 pandemic disrupted routine healthcare and animal health programs worldwide, raising concerns about the continuity of rabies prevention strategies. This study evaluates the impact of the pandemic on post-exposure prophylaxis (PEP) administration in Serbia and North Macedonia, two Balkan countries historically considered at risk of rabies circulation. We conducted a retrospective analysis of medical records from the Pasteur Institute Novi Sad (PINS, Serbia) and the Clinic for Infectious Diseases in Skopje (CIDS, North Macedonia), comparing pre-pandemic (2018–2019) and post-pandemic (2022–2024) periods. A total of 5,128 patient records were included, with dog bites accounting for the majority of exposures in both countries. Findings revealed a significant increase in PEP administration in North Macedonia, rising from 6.7% to 16.4% of bite patients after the pandemic ( p < 0.001), while Serbia maintained stable rates (0.98% to 1.65%, p > 0.05). Differences likely reflect disparities in rabies surveillance, information flow between veterinary and medical sectors, and the organization of national control programs. These results underscore the importance of integrated One Health approaches and real-time information exchange to optimize rabies prevention and ensure resilience against future disruptions.
Mechanically Interlocked Indigo Photoswitches
ABSTRACT Photoswitches provide the opportunity to remotely and precisely control matter on the nanoscopic scale. For many materials and biological applications, photoswitches with long wavelength response are essential; however, few switches offer inherent response to red/near infra‐red light. Previous works have described the use of intermolecular interactions as a method to redshift the activation wavelength of photoswitches and to improve thermal half‐life. However, these systems are limited in their application due to the inherent bimolecularity of this strategy preventing its use in dilute or complex environments. Herein, we describe the use of topologically constrained supramolecular interactions to improve the switching properties of an indigo photoswitch within a [2]‐rotaxane. This enabled photoswitching with 730 nm light, as well as a 100‐fold increase in thermal half‐life and double the population of the metastable state under constant irradiation. This surpasses previous attempts at using supramolecular interactions to increase the thermal half‐life by >10‐fold. This novel strategy towards the redshifting and fine‐tuning of these molecular photoswitches has implications for the design of molecular machines and applied switching technologies. We anticipate that our insights into the design of such molecules will unlock new applications for mechanically interlocked molecules.
Computational identification of putative GyrA and AcrR inhibitors from gut microbiota and natural products targeting multidrug-resistant Salmonella enterica
Enabling Moisture and Interfacial Stability in Sulfide Solid Electrolytes via a Processable Organic Coating Strategy for High‐Voltage All‐Solid‐State Batteries
ABSTRACT Sulfide solid electrolytes (SEs) are excellent candidates for solid‐state batteries (SSBs), but their extreme sensitivity to moisture and lack of oxidative stability with uncoated high‐voltage cathodes incur processing complexity and cost. Here, we present a simple and cost‐effective decanoate fatty‐acid (DA) coating strategy for argyrodite (Li 6 PS 5 Cl, LPSCl) that stabilizes it to exposure at 39% relative humidity for up to 2 h, while preserving its structure, ionic conductivity, and increasing its anodic stability. Cells employing 2 wt%‐coated LPSCl (DA–LPSCl) as the catholyte, with a bare NCM85 cathode and Li‐In anode, deliver a capacity of 175 mAh.g −1 , and 96% capacity retention over 150 cycles at 0.2 C, while bare LPSCl retains only 61% capacity. Symmetric Li|DA–LPSCl|Li cells cycle for 1000 h, in contrast to bare LPSCl cells, which short‐circuit after ∼230 h. Moreover, full cells using a lithium metal anode with the DA–LPSCl SE showed remarkable performance compared to state‐of‐the‐art SSBs, retaining 81% of their capacity after 300 cycles at 0.2 C. High‐loading cells with areal capacities up to 3.2 mAh cm −2 are also demonstrated. This work showcases the potential of a low‐cost, processable, and flexible coating to address key limitations of sulfide SEs, advancing the commercial viability of SSBs.
A soft-switching hybrid boost–buck PFC converter for high power quality EV battery charging applications
Self‐Cleaning Solar Evaporation Facilitating Water Electrolysis for Hydrogen Generation From Seawater
ABSTRACT Clean energy demands and zero‐carbon commitments have stimulated the desire for stable seawater electrolysis, yet device corrosion and catalyst deactivation seriously hinder industrial‐scale deployment. Here we present an innovative integrated platform that couples photothermal evaporation and desalinated water electrolysis. Relying on a hydrogen‐bonding crosslinking mechanism and anion‐induced Hofmeister effects, a lightweight spherical evaporator uniformly coated with a modified needle coke gel film is designed, exhibiting attractive continuous desalination performance (2.32 kg m −2 h −1 in 3.5 wt%) and salt‐resistant self‐cleaning capabilities. Subsequently, two independently improved evaporation‐collection systems outperform the traditional configuration during extended all‐weather outdoor experiments. Especially, the gas‐stripping assisted evaporation system holds powerful resistance capacity to adverse weather, achieving 5 times more water yield on a rainy day. Importantly, their seamless adaptation to anion/cation exchange membrane electrolysis systems has pioneered the long‐term application of advanced membrane electrodes in desalinated water electrolysis, cleverly addressing corrosion and catalyst deactivation barriers. This integrated strategy provides a practicable route for energy‐saving and large‐scale hydrogen extraction from seawater.
Consensus-based local data aggregation in wireless sensor networks under node failures and transmission-power-based topology control
Chiral Spiro‐Scaffolded C(sp <sup>3</sup> ),P‐Chelated Iridacycles: Direct Asymmetric Hydrogenation of β,β‐Disubstituted Acrylate Salts
ABSTRACT Rational design of chiral ligands with precisely tailored steric and electronic properties is pivotal to advancing asymmetric transition‐metal catalysis. Despite their promising strong σ‐donating ability, sp 3 ‐hybridized carbanion ligands have long been underexplored owing to the inherent instability of C(sp 3 )‐metalated complexes. In this study, we report a modular design of chiral spiro monophosphine ligands (( R )‐SciPhos) integrating an electronic‐withdrawing group, a quaternary carbon moiety, and a rigid spiro scaffold, which efficiently addresses this long‐standing challenge. This judicious design enables the synthesis of bench‐stable neutral C(sp 3 ),P‐chelated iridium complexes via intramolecular C─H activation. These novel iridacycle catalysts exhibit high efficiency, excellent enantioselectivity, and a broad substrate scope in the asymmetric hydrogenation of challenging β,β‐disubstituted sodium acrylates, achieving up to 99% yield and 97% ee with a turnover number (TON) of 5000. Mechanistic studies reveal an Ir(III)/Ir(V) catalytic cycle involving an olefin dihydride iridium(III) intermediate, wherein the migratory insertion step dictates enantioselectivity via noncovalent interactions. This work establishes a general platform for C(sp 3 )‐metalated complex‐based catalysis, opens new avenues for the development of innovative asymmetric catalytic systems, and unlocks access to previously inaccessible enantioselective transformations.
Hormetic responses of niger (Guizotia abyssinica Cass.) to imazethapyr under field conditions
Oxygen Bridge‐Induced Spin‐State Engineering Enables Solvation‐Barrier‐Free Sulfur Redox Kinetics in Lithium‐Sulfur Batteries
ABSTRACT Lithium‐sulfur (Li‐S) batteries are attractive for next‐generation energy storage, yet practical deployment is impeded by the lithium polysulfides (LiPSs) shuttle effect and sluggish sulfur redox kinetics, which are further aggravated by solvent shielding that blocks LiPSs from accessing catalytic sites. Here, we develop a yolk‐shell MoO 3 /Co 3 O 4 @C nanoreactor that leverages oxygen bridge‐induced orbital oscillation to break the solvation barrier and accelerate interfacial conversion. We identify that the dynamic vibration of Mo‐O‐Co oxygen bridges facilitates a directional electron flow via a 4 d ‐2 p ‐3 d orbital interaction pathway, which fundamentally triggers a low‐spin to high‐spin transition of Co centers, strengthening d ‐ p orbital hybridization and enabling robust chemisorption/catalysis of LiPSs. Meanwhile, the modulation of solvation structure from solvent‐separated ion pairs (SSIPs) to contact ion pairs (CIPs)/aggregates (AGGs) lowers the Li + desolvation energy barrier and homogenizes the ion flux. Synergistically, the double‐shelled architecture confines soluble intermediates and suppresses outward diffusion. Consequently, Li‐S batteries deliver 352 mAh g −1 at an ultrahigh rate of 15 C, and an initial areal capacity of 11.95 mAh cm −2 is achieved at an ultrahigh sulfur loading of 13.03 mg cm −2 . This work proposes a strategy of oxygen‐bridge‐induced high‐spin state to realize desolvation and mass‐transfer reaction of LiPSs within interface catalytic domain.
A slope system in an intracontinental rift setting: the record from Western Gondwana in the Santos Basin, Brazil
Abstract This study investigates a rift-related lacustrine slope system characterized by authigenic high-magnesium phyllosilicates (e.g., kerolite-stevensite) and carbonates associated with volcaniclastic deposits. By integrating high-resolution 3D seismic data in the depth domain with multi-attribute blending (Dip, Azimuth, and Maximum Curvature), we reconstructed the structural framework, stratigraphic geometries, and 3D morphology of depositional elements. Lithological calibration was achieved through thin sections and cores, supporting the geomorphological characterization. Results reveal a complex slope system controlled by NE-SW normal faults, dipping ~ 30° SE over a 40 km strike, with maximum accumulated vertical throw of 2000 m. This system is segmented by NW-SE and W-E faults to the north and south, respectively. Stratigraphic analysis identifies proximal onlap and distal downlap along early syn-rift fault scarps (Piçarras Formation), followed by the onlap of the late syn-rift (Itapema Formation) and early post-rift (Barra Velha Formation), characterizing a bypass margin. In contrast, the late post-rift Barra Velha Formation marks the development of a platform basin on the hanging wall, featuring linearly aligned mounds transitioning downdip into a flat-topped platform. Its margin is defined by arcuate mounds and a slope characterized by gullies, slumps, fans, and aprons, signaling an evolution toward an accretionary margin. Despite the alkaline lacustrine setting, the post-rift slope system exhibits striking similarities to marine analogues, suggesting shared depositional processes and responses.
Breaking the Linear Scaling Relationship: Bioinspired Electronic Coupling in S‐Bridged Fe−Fe Dual Sites for Efficient Oxygen Reduction
ABSTRACT Dual‐atom catalysts (DACs) provide a promising approach to overcome the linear scaling relationship that limits the activity of single‐atom catalysts for oxygen reduction reactions (ORR). However, the lack of a direct electronic bridge between the two sites, along with the inherently localized character of transition‐metal 3d orbitals, often hinders coherent electronic regulation and efficient orbital overlap with reaction intermediates. Herein, inspired by the natural iron‐sulfur clusters, we design an S‐bridged Fe−Fe DAC (Fe 2 N 6 ‐S/SNC). The sulfur bridge acts as an intrinsic charge‐transfer channel, enabling strong electronic coupling between the Fe centers. Combined experimental and theoretical analyses demonstrate that this configuration promotes dynamic charge redistribution and enhances Fe 3d‐S 2p orbital hybridization, which cooperatively optimizes oxygen intermediate adsorption and enhances the ORR kinetics. Consequently, Fe 2 N 6 ‐S/SNC exhibits outstanding alkaline ORR performance with a half‐wave potential of 0.93 V, a kinetic current of 35.40 A g −1 , and a high turnover frequency of 2.49 e − site −1 s −1 . When integrated into an ampere‐hour‐scale zinc‐air battery, it delivers a discharge capacity of 4.76 Ah and a peak power of 2.67 W. This work demonstrates a bio‐inspired bridging strategy to create electronically coherent dual‐atom sites, offering fresh perspectives on the rational design of high‐performance DACs for energy conversion devices.