A composite electrocatalyst,CoMoNiO-S/NF-110(NF is nickel foam),was synthesized through electrodeposition,followed by pyrolysis and then the vulcanization process.CoMoNiO-S/NF-110 exhibited a structure where Ni3S2 and...A composite electrocatalyst,CoMoNiO-S/NF-110(NF is nickel foam),was synthesized through electrodeposition,followed by pyrolysis and then the vulcanization process.CoMoNiO-S/NF-110 exhibited a structure where Ni3S2 and Mo2S3 nanoparticles were integrated at the edges of Co3O4 nanosheets,creating a rich,heterogeneous interface that enhances the synergistic effects of each component.In an alkaline electrolyte,the synthesized CoMoNiO-S/NF-110 exhibited superior electrocatalytic performance for oxygen evolution reaction(OER),achieving current densities of 100 and 200 mA·cm^(-2) with low overpotentials of 199.4 and 224.4 mV,respectively,outperforming RuO2 and several high-performance Mo and Ni-based catalysts.This excellent performance is attributed to the rich interface formed between the components and active sites exposed by the defect structure.展开更多
The poor electrical conductivity of metal-organic frameworks(MOFs)limits their electrocatalytic performance in the oxygen evolution reaction(OER).In this study,a Py@Co-MOF composite material based on pyrene(Py)molecul...The poor electrical conductivity of metal-organic frameworks(MOFs)limits their electrocatalytic performance in the oxygen evolution reaction(OER).In this study,a Py@Co-MOF composite material based on pyrene(Py)molecules and{[Co2(BINDI)(DMA)_(2)]·DMA}_(n)(Co-MOF,H4BINDI=N,N'-bis(5-isophthalic acid)naphthalenediimide,DMA=N,N-dimethylacetamide)was synthesized via a one-pot method,leveragingπ-πinteractions between pyrene and Co-MOF to modulate electrical conductivity.Results demonstrate that the Py@Co-MOF catalyst exhibited significantly enhanced OER performance compared to pure Co-MOF or pyrene-based electrodes,achieving an overpotential of 246 mV at a current density of 10 mA·cm^(-2) along with excellent stability.Density functional theory(DFT)calculations reveal that the formation of O*in the second step is the rate-determining step(RDS)during the OER process on Co-MOF,with an energy barrier of 0.85 eV due to the weak adsorption affinity of the OH*intermediate for Co sites.CCDC:2419276.展开更多
Refractory metals,including tungsten(W),tantalum(Ta),molybdenum(Mo),and niobium(Nb),play a vital role in industries,such as nuclear energy and aerospace,owing to their exceptional melting temperatures,thermal durabili...Refractory metals,including tungsten(W),tantalum(Ta),molybdenum(Mo),and niobium(Nb),play a vital role in industries,such as nuclear energy and aerospace,owing to their exceptional melting temperatures,thermal durability,and corrosion resistance.These metals have body-centered cubic crystal structure,characterized by limited slip systems and impeded dislocation motion,resulting in significant low-temperature brittleness,which poses challenges for the conventional processing.Additive manufacturing technique provides an innovative approach,enabling the production of intricate parts without molds,which significantly improves the efficiency of material usage.This review provides a comprehensive overview of the advancements in additive manufacturing techniques for the production of refractory metals,such as W,Ta,Mo,and Nb,particularly the laser powder bed fusion.In this review,the influence mechanisms of key process parameters(laser power,scan strategy,and powder characteristics)on the evolution of material microstructure,the formation of metallurgical defects,and mechanical properties were discussed.Generally,optimizing powder characteristics,such as sphericity,implementing substrate preheating,and formulating alloying strategies can significantly improve the densification and crack resistance of manufactured parts.Meanwhile,strictly controlling the oxygen impurity content and optimizing the energy density input are also the key factors to achieve the simultaneous improvement in strength and ductility of refractory metals.Although additive manufacturing technique provides an innovative solution for processing refractory metals,critical issues,such as residual stress control,microstructure and performance anisotropy,and process stability,still need to be addressed.This review not only provides a theoretical basis for the additive manufacturing of high-performance refractory metals,but also proposes forward-looking directions for their industrial application.展开更多
The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor ...The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor featuring a broad spectral absorption range,is successfully employed as the electron acceptor to combine with CdS for constructing a S-scheme heterojunction.The optimized photocatalyst(CdSCuO2∶1)delivers an exceptional hydrogen evolution rate of 18.89 mmol/(g·h),4.15-fold higher compared with bare CdS.X-ray photoelectron spectroscopy(XPS)and ultraviolet-visible diffuse reflection absorption spectroscopy(UV-vis DRS)confirmed the S-scheme band structure of the composites.Moreover,the surface photovoltage(SPV)and electron paramagnetic resonance(EPR)indicated that the photogenerated electrons and photogenerated holes of CdS-CuO2∶1 were respectively transferred to the conduction band(CB)of CdS with a higher reduction potential and the valence band(VB)of CuO with a higher oxidation potential under illumination,as expected for the S-scheme mechanism.Density-functional-theory calculations of the electron density difference(EDD)disclose an interfacial electric field oriented from CdS to CuO.This built-in field suppresses charge recombination and accelerates carrier migration,rationalizing the markedly enhanced PHE activity.This study offers a novel strategy for designing S-scheme heterojunctions with high light harvesting and charge utilization toward sustainable solar-tohydrogen conversion.展开更多
Ruthenium-based materials(Ru and RuO_(2))are promising electrocatalysts toward electrochemical water splitting(EWS)though there are still issues with them that needs to be resolved such as relatively strong adsorption...Ruthenium-based materials(Ru and RuO_(2))are promising electrocatalysts toward electrochemical water splitting(EWS)though there are still issues with them that needs to be resolved such as relatively strong adsorption strength of intermediates over Ru and oxidative dissolution of RuO_(2).In this article,an overview of the recent progress and challenges with Ru-based electrocatalysts for EWS is provided.Firstly,fundamentals of EWS are summarized from the aspects of reaction mechanisms and activity descriptors.Next,the typical methods of fabricating Ru-based catalysts are demonstrated mainly including hydrothermal/solvothermal syntheses,organic ligand-assisted syntheses,pyrolysis,acid etching,cation exchange methods and molten salt-assisted syntheses.We then focus on illustrating the enhancing strategies toward creating advanced Ru-based electrocatalysts by demonstrating the typical examples,which include alloying,doping,structure design,interface engineering,single-atom catalyst design,high-entropy alloy design,phase engineering and defecting engineering.In this section,the structureproperty correlation is elucidated aiming to the design of more efficient Ru-based electrocatalysts for EWS.Finally,we conclude the review by addressing the challenges and prospects of electrochemical water splitting and the development of Rubased catalysts.展开更多
The large-scale application of water electrolysis for H_(2) production is hindered by the sluggish kinetics of the anodic oxygen evolution reaction(OER).To improve the efficiency of water electrolyzers,numerous effort...The large-scale application of water electrolysis for H_(2) production is hindered by the sluggish kinetics of the anodic oxygen evolution reaction(OER).To improve the efficiency of water electrolyzers,numerous efforts have been devoted to developing robust OER catalysts.Among them,Ni-based materials have been identified as state-of-the-art catalysts in alkaline conditions due to their high catalytic activity[1,2].During OER,these catalysts can undergo surface reconstruction and form(oxy)hydroxide species on the surface,which is the real active phase and its chemistry determines the OER performance[3].展开更多
The genus Clematis(Ranunculaceae)comprises over 300 species with remarkable morphological and ecological diversity worldwide.Despite its horticultural,medicinal,and ecological importance,a well-resolved phylogeny and ...The genus Clematis(Ranunculaceae)comprises over 300 species with remarkable morphological and ecological diversity worldwide.Despite its horticultural,medicinal,and ecological importance,a well-resolved phylogeny and coherent infrageneric classification are still lacking.Here,we reconstruct a robust phylogeny for Clematis using a phylogenomic approach and revise its infrageneric taxonomy.We incorporated 198 samples representing 151 species,two subspecies,and 12 varieties,covering all subgenera and most sections worldwide,obtained from both fresh and herbarium material.Nuclear single nucleotide polymorphisms(SNPs)and complete plastid genomes were assembled for phylogenetic analyses.We also prepared a nuclear ribosomal ITS(nrITS)dataset comprising 171 species,two subspecies,and 12 varieties(217 samples)to include as many species as possible for phylogenetic inference.Phylogenies based on plastid genomes and nrITS exhibited limited resolution and modest support,highlighting challenges in resolving certain relationships.Nuclear SNP analyses yielded a robust phylogenetic tree with 22 well-supported clades corresponding to 22 sections,with most previously recognized subgenera and sections not recovered as monophyletic.Ancestral state reconstruction of 12 key morphological characters revealed multiple independent origins of character states.This study presents the first comprehensive sectional classification for Clematis based on robust phylogenomic evidence,redefines morphological characteristics for each section,and resolves long-standing taxonomic ambiguities.Our results establish a framework for future studies on the evolution,ecology,and horticultural potential of this globally significant genus.展开更多
Developing efficient and durable electrocatalysts for acidic oxygen evolution reaction(OER)is pivotal for advancing proton exchange membrane water electrolysis(PEMWEs),yet balancing activity and stability remains a fo...Developing efficient and durable electrocatalysts for acidic oxygen evolution reaction(OER)is pivotal for advancing proton exchange membrane water electrolysis(PEMWEs),yet balancing activity and stability remains a formidable challenge.Herein,we propose a dual-engineering strategy to stabilize Ru-based catalysts by synergizing the oxygen vacancy site-synergized mechanism-lattice oxygen mechanism(OVSM-LOM)with Ru-N bond stabilization.The engineered RuO_(2)@NCC catalyst exhibits exceptional OER performance in 0.5 M H2SO4,achieving an ultralow overpotential of 215 mV at 10 mA cm^(-2) and prolonged stability for over 327 h.The catalyst delivers 300 h of continuous operation at 1 A cm^(-2),with a negligible degradation rate of only 0.067 mV h-1,further demonstrating its potential for practical application.Oxygen vacancies unlock the OVSM-LOM pathway,bypassing the sluggish adsorbate evolution mechanism(AEM)and accelerating reaction kinetics,while the Ru-N bonds suppress Ru dissolution by anchoring low-valent Ru centers.Quasi-in situ X-ray photoelectron spectroscopy(XPS),X-ray absorption spectroscopy(XAS),and isotopic labeling experiments confirm the lattice oxygen participation with *O formation as the rate-determining step.The Ru-N bonds reinforce the structural integrity by stabilizing low-valent Ru centers and inhibiting overoxidation.Theoretical calculations further verify that the synergistic interaction between OVs and Ru-O(N)active sites optimizes the Ru d-band center and stabilizes intermediates,while Ru-N coordination enhances structural integrity.This study establishes a novel paradigm for designing robust acidic OER catalysts through defect and coordination engineering,bridging the gap between activity and stability for sustainable energy technologies.展开更多
This study presents a comprehensive phylogenetic analysis on Batrachospermaceae based on key taxonomic identifiers(rbcL,psaA,psbA,and COI-5P)from some genera.To systematically explore the phylogenetic relationships an...This study presents a comprehensive phylogenetic analysis on Batrachospermaceae based on key taxonomic identifiers(rbcL,psaA,psbA,and COI-5P)from some genera.To systematically explore the phylogenetic relationships and taxonomy within Batrachospermaceae,we integrated molecular and morphological data,and explored the phylogeny,character evolution,and ancestral geographical origin and provided a theoretical support for the classification and geographic origination of Batrachospermaceae.Our findings reveal distinct relationships within the phylogenetic tree.Notably,10 genera(Sirodotia,Batrachospermum,Tuomeya,Volatus,Lympha,Nothocladus,Torularia,Sheathia,Nocturama,and Petrohua)are closely associated in the rbcL phylogenetic tree.Additionally,four genera(Kumanoa,Hoefkenia,Notohesperus,and Virescentia)exhibit high support ratios,indicating their close interrelations.Other genera,including Paludicola,Visia,Acarposporophycos,Macrosporophycos,Visioidea,Balliopsis,and Psilosiphon,exhibit clustering traits.Furthermore,the multigene sequences provide a robust support for Montagnia that forms a monophyletic group.Ancestral reconstruction of morphological characters identifies nine primitive character states,including whorl,fascicle length,cortical cells,secondary fascicles,the shape of carpogonical branch,spermatangia,carposporophyte,carpogonium and trichogyne,with Visia likely representing ancestral traits in Batrachospermaceae.Furthermore,geographical origin maps suggest a potential common ancestral of Batrachospermaceae origin in the American continent.Additional to conventional analyses,including evolutionary and ancestral reconstruction investigations into key morphological characters,we attempt to reconstruct the biogeography within the Batrachospermaceae,thus contributing to a nuanced understanding of its origin.展开更多
Stephanodiscaceae is one of the most diverse family of the freshwater centric diatoms.However,the scarcity of whole plastome data poses a significant challenge to the undertaking of genomic studies on this taxonomic g...Stephanodiscaceae is one of the most diverse family of the freshwater centric diatoms.However,the scarcity of whole plastome data poses a significant challenge to the undertaking of genomic studies on this taxonomic group.We collected data on the plastid genomes from 33 members of the Stephanodiscaceae and its close relatives,including 12 newly-sequenced genomes and 21 deposited in National Center for Biotechnology Information(NCBI).Phylogenetic trees are yielded five major clades based on homologous genes.The features of the plastid genomes,including repeat sequences,codon usage,and selection pressure for each clade,are analyzed.The paper makes a contribution to the field of diatom genomics by describing the structural characteristics of the plastid genomes in the Stephanodiscaceae and its closely related species,complemented by related analyses.It provides crucial data that will serve as indispensable references for future research.展开更多
Rock brittleness is a critical property in geotechnical and energy engineering,as it directly influences the prediction of rock failure and stability assessment.Although numerous methods have been developed to evaluat...Rock brittleness is a critical property in geotechnical and energy engineering,as it directly influences the prediction of rock failure and stability assessment.Although numerous methods have been developed to evaluate brittleness,many fail to comprehensively account for the impacts of microstructural changes,mineralogical characteristics,and stress conditions on energy evolution during failure.This study proposes a novel approach for brittleness evaluation based on the energy evolution throughout the post-peak failure process,integrating two micromechanical mechanisms:crack propagation and frictional sliding.A new brittleness index is defined as the ratio of generated surface energy to released elastic energy,providing a unified framework for assessing both Class I and Class II mechanical behaviors.The brittleness of cyan,white,and gray sandstones was investigated under various confining pressures and moisture conditions using X-ray diffraction(XRD),scanning electron microscopy(SEM),and conventional triaxial compression(CTC)tests.The results demonstrate that brittleness decreases with increasing confining pressure,due to suppressed crack propagation,and increases under saturated conditions,as moisture enhances crack propagation.By establishing connections between mineral composition,microstructural features,and stress-induced responses,the proposed method overcame limitations of previous approaches and offered a more precise tool for evaluating rock brittleness under diverse environmental scenarios.展开更多
After billions of years of evolution,biological intelligence has converged on unrivalled energy efficiency and environmental adaptability.The human brain,for instance,is highly efficient in information transmission,co...After billions of years of evolution,biological intelligence has converged on unrivalled energy efficiency and environmental adaptability.The human brain,for instance,is highly efficient in information transmission,consuming only about 20 W onaverage in a resting state[1,2].A key to this efficiency is that biological signal transduction and processing rely significantly on multi-ions as the signal carriers.Inspired by this paradigm.展开更多
Background:Tandem gene repeats naturally occur as important genomic features and determine many traits in living organisms,like human diseases and microbial productivities of target bioproducts.Methods:Here,we develop...Background:Tandem gene repeats naturally occur as important genomic features and determine many traits in living organisms,like human diseases and microbial productivities of target bioproducts.Methods:Here,we developed a bacterial type-II toxin-antitoxin-mediated method to manipulate genomic integration of tandem gene repeats in Saccharomyces cerevisiae and further visualised the evolutionary trajectories of gene repeats.We designed a tri-vector system to introduce toxin-antitoxin-driven gene amplification modules.Results:This system delivered multi-copy gene integration in the form of tandem gene repeats spontaneously and independently from toxin-antitoxin-mediated selection.Inducing the toxin(RelE)expressing via a copper(II)-inducible CUP1 promoter successfully drove the in-situ gene amplification of the antitoxin(RelB)module,resulting in~40 copies of a green fluorescence reporter gene per copy of genome.Copy-number changes,copy-number increase and copy-number decrease,and stable maintenance were visualised using the green fluorescence protein and blue chromoprotein AeBlue as reporters.Copy-number increases happened spontaneously and independent on a selection pressure.Increased copy number was quickly enriched through toxin-antitoxin-mediated selection.Conclusion:In summary,the bacterial toxin-antitoxin systems provide a flexible mechanism to manipulate gene copy number in eukaryotic cells and can be exploited for synthetic biology and metabolic engineering applications.展开更多
To realize the practical application of anion exchange membrane water electrolysis(AEMWE),it is essential to develop highly active,durable,and cost-effective electrocatalyst for oxygen evolution reaction(OER).Herein,w...To realize the practical application of anion exchange membrane water electrolysis(AEMWE),it is essential to develop highly active,durable,and cost-effective electrocatalyst for oxygen evolution reaction(OER).Herein,we report a hollow-structured Ni_(x)Co_(1−x)O/Ni_(3)S_(2)/Co_(9)S_(8)heterostructure synthesized via sequential template-assisted growth,thermal oxidation,and controlled sulfidation process.The abundant bimetallic heterointerfaces not only provide additional active sites but also promote electronic modulation via charge redistribution.Additionally,the porous and hollow architecture enhances active surface area and mass transfer ability,thereby increasing the number of accessible active sites for alkaline OER.As a result,the prepared electrocatalyst achieves low overpotential of 310 mV at 10 mA cm^(−2)and small Tafel slope of 55.94 mV dec^(−1),demonstrating the exceptional electrocatalytic performance for alkaline OER.When integrated as the anode in an AEMWE cell,it delivers outstanding performance with only 1.657 V at 1.0 A cm^(−2)and reaches high current density of 5.0 A cm^(−2)at 1.989 V,surpassing those of commercial RuO_(2).The cell also shows excellent long-term durability over 100 h with minimal degradation.This study highlights the strong potential of rationally engineered oxide/sulfide heterostructures for next-generation alkaline water electrolysis.展开更多
Developing catalysts with excellent stability while significantly reducing the overpotential of the oxygen evolution reaction(OER) is crucial for advancing overall water splitting(OWS) systems.In this study,we synthes...Developing catalysts with excellent stability while significantly reducing the overpotential of the oxygen evolution reaction(OER) is crucial for advancing overall water splitting(OWS) systems.In this study,we synthesized the electrode material Ce-NiCo-LDHs@SnO_(2)/NF through a two-step hydrothermal reaction,where Ce-doped NiCo-LDHs are grown on nickel foam modified by a SnO_(2) layer.Ce doping adjusts the internal electronic distribution of Ni Co-LDHs,while the introduction of the SnO_(2) layer enhances electron transfer capability.Together,these factors contribute to the reduction of the OER energy barrier and experimental evidence confirms that the reaction proceeds via the lattice oxygen evolution mechanism(LOM).Consequently,Ce-NiCo-LDHs@SnO_(2)/NF exhibits high level electrochemical performance in OER,requiring only 234 m V overpotential to achieve a current density of 10 m A/cm^(2),with a Tafel slope of just 27.39 m V/dec.When paired with Pt/C/NF,an external potential of only 1.54 V is needed to drive OWS to attain a current density amounting to 10 m A/cm^(2).Furthermore,the catalyst demonstrates stability for 100 h during the OWS stability test.This study underscores the feasibility of enhancing the OER performance through Ce doping and the introduction of a conductive SnO_(2) layer.展开更多
Centromeres are indispensable for accurate chromosome segregation,but are subject to rapid sequence turnover while maintaining conserved functions--a paradox in genome evolution.To unravel this paradox,we integrated o...Centromeres are indispensable for accurate chromosome segregation,but are subject to rapid sequence turnover while maintaining conserved functions--a paradox in genome evolution.To unravel this paradox,we integrated over 400 fully resolved centromeres from 17 diploid angiosperms spanning 180 million years of divergence,along with 1,000+pan-genomic assemblies,resequencing datasets,and congeneric wholegenome sequences.We showed that angiosperm centromere organization is determined by lineagespecific combinations of satellite repeats and transposable elements(TEs),which,in turn,shape distinct epigenetic landscapes and evolutionary trajectories within centromeres.In particular,TE insertion patterns were found to be key drivers of structural diversification and positional shift of centromeres in angiosperms.Intriguingly,population-level analyses revealed considerable plasticity in centromere sequences across species,with satellite repeats serving as focal points of evolutionary change and exhibiting species-specific heterogeneity patterns.Temporal reconstructions across congeneric species revealed the emergence and subsequent differentiation of centromeric repeats,outlining a dynamic continuum from gradual sequence diversification to complete turnover during speciation,often accompanied by karyotype reorganization.By integrating intra-and inter-species comparisons,we propose a unifying framework in which centromere innovation is governed by a delicate interplay between genome evolution,chromosomal shuffling,and selection constraints,resulting in phylogenomic signatures of centromeredriven speciation.展开更多
The capacity of the central nervous system for structural plasticity and regeneration is commonly believed to show a decreasing progression from“small and simple”brains to the larger,more complex brains of mammals.H...The capacity of the central nervous system for structural plasticity and regeneration is commonly believed to show a decreasing progression from“small and simple”brains to the larger,more complex brains of mammals.However,recent findings revealed that some forms of neural plasticity can show a reverse trend.Although plasticity is a well-preserved,transversal feature across the animal world,a variety of cell populations and mechanisms seem to have evolved to enable structural modifications to take place in widely different brains,likely as adaptations to selective pressures.Increasing evidence now indicates that a trade-off has occurred between regenerative(mostly stem cell–driven)plasticity and developmental(mostly juvenile)remodeling,with the latter primarily aimed not at brain repair but rather at“sculpting”the neural circuits based on experience.In particular,an evolutionary trade-off has occurred between neurogenic processes intended to support the possibility of recruiting new neurons throughout life and the different ways of obtaining new neurons,and between the different brain locations in which plasticity occurs.This review first briefly surveys the different types of plasticity and the complexity of their possible outcomes and then focuses on recent findings showing that the mammalian brain has a stem cell–independent integration of new neurons into pre-existing(mature)neural circuits.This process is still largely unknown but involves neuronal cells that have been blocked in arrested maturation since their embryonic origin(also termed“immature”or“dormant”neurons).These cells can then restart maturation throughout the animal's lifespan to become functional neurons in brain regions,such as the cerebral cortex and amygdala,that are relevant to high-order cognition and emotions.Unlike stem cell–driven postnatal/adult neurogenesis,which significantly decreases from small-brained,short-living species to large-brained ones,immature neurons are particularly abundant in large-brained,long-living mammals,including humans.The immature neural cell populations hosted in these complex brains are an interesting example of an“enlarged road”in the phylogenetic trend of plastic potential decreases commonly observed in the animal world.The topic of dormant neurons that covary with brain size and gyrencephaly represents a prospective turning point in the field of neuroplasticity,with important translational outcomes.These cells can represent a reservoir of undifferentiated neurons,potentially granting plasticity within the high-order circuits subserving the most sophisticated cognitive skills that are important in the growing brains of young,healthy individuals and are frequently affected by debilitating neurodevelopmental and degenerative disorders.展开更多
A core-shell type Co_(19)-added polyoxometalate H_(17)Na_(4)Cs_(21)[Co_(19)(μ_(3)-OH)_(12)(A-α-SiW_(10)O_(37))_(6)]·8 Cl·12H_(2)O(1)has been made under hydrothermal conditions guided by the lacunary direct...A core-shell type Co_(19)-added polyoxometalate H_(17)Na_(4)Cs_(21)[Co_(19)(μ_(3)-OH)_(12)(A-α-SiW_(10)O_(37))_(6)]·8 Cl·12H_(2)O(1)has been made under hydrothermal conditions guided by the lacunary directing synthetic strategy.Single crystal X-ray diffraction(SXRD)has shown that 19 Co^(2+)are arranged in a flat plane through edge sharing in a mode of 3-4-5-4-3,forming a core-shell type polyanion cluster{Co_(19)(SiW_(10))_6}with a diameter of approximately 2.24 nm.Visible-light-driven photocatalytic hydrogen evolution performance studies have shown that 1 is an efficient heterogeneous water reduction catalyst(WRC)with the H_(2)evolution rate of 2902.5μmol h^(-1)g^(-1).Moreover,the cycle tests indicated that 1 was also a good heterogeneous catalyst.展开更多
Cloud data sharing is an important issue in modern times.To maintain the privacy and confidentiality of data stored in the cloud,encryption is an inevitable process before uploading the data.However,the centralized ma...Cloud data sharing is an important issue in modern times.To maintain the privacy and confidentiality of data stored in the cloud,encryption is an inevitable process before uploading the data.However,the centralized management and transmission latency of the cloud makes it difficult to support real-time processing and distributed access structures.As a result,fog computing and the Internet of Things(IoT)have emerged as crucial applications.Fog-assisted proxy re-encryption is a commonly adopted technique for sharing cloud ciphertexts.It allows a semitrusted proxy to transforma data owner’s ciphertext into another re-encrypted ciphertext intended for a data requester,without compromising any information about the original ciphertext.Yet,the user revocation and cloud ciphertext renewal problems still lack effective and secure mechanisms.Motivated by it,we propose a revocable conditional proxy re-encryption scheme offering ciphertext evolution(R-CPRE-CE).In particular,a periodically updated time key is used to revoke the user’s access privileges while an access condition prevents a malicious proxy from reencrypting unauthorized ciphertext.We also demonstrate that our scheme is provably secure under the notion of indistinguishability against adaptively chosen identity and chosen ciphertext attacks in the random oracle model.Performance analysis shows that our scheme reduces the computation time for a complete data access cycle from an initial query to the final decryption by approximately 47.05%compared to related schemes.展开更多
Thermal-mechanical damage and deformation at the interface between shotcrete linings and the surrounding rock of tunnels under high-temperature and variable-temperature conditions are critical to the safe construction...Thermal-mechanical damage and deformation at the interface between shotcrete linings and the surrounding rock of tunnels under high-temperature and variable-temperature conditions are critical to the safe construction and operation of tunnel engineering.This study investigated the thermo-mechanical damage behavior of the composite interface between alkali-resistant glass fiber-reinforced concrete(ARGFRC)and granite,focusing on a plateau railway tunnel.Laboratory triaxial tests,laser scanning,XRD analysis,numerical simulations,and theoretical analyses were employed to investigate how different initial curing temperatures and joint roughness coefficient(JRC)influence interfacial damage behavior.The results indicate that an increase in interface roughness exacerbates the structural damage at the interface.At a JRC of 19.9 and a temperature of 70℃,crack initiation in granite was notably restrained when the confining pressure rose from 7 MPa to 10 MPa.Roughness-induced stress distribution at the interface was notably altered,although this effect became less pronounced under high confining pressure conditions.Additionally,during high-temperature curing,thermal stress concentration at the tips of micro-convex protrusions on the granite surface induced microcracks in the adjacent ARGFRC matrix,followed by deformation.These findings provide practical guidelines for designing concrete support systems to ensure tunnel structural safety in high-altitude regions with harsh thermal environments.展开更多
文摘A composite electrocatalyst,CoMoNiO-S/NF-110(NF is nickel foam),was synthesized through electrodeposition,followed by pyrolysis and then the vulcanization process.CoMoNiO-S/NF-110 exhibited a structure where Ni3S2 and Mo2S3 nanoparticles were integrated at the edges of Co3O4 nanosheets,creating a rich,heterogeneous interface that enhances the synergistic effects of each component.In an alkaline electrolyte,the synthesized CoMoNiO-S/NF-110 exhibited superior electrocatalytic performance for oxygen evolution reaction(OER),achieving current densities of 100 and 200 mA·cm^(-2) with low overpotentials of 199.4 and 224.4 mV,respectively,outperforming RuO2 and several high-performance Mo and Ni-based catalysts.This excellent performance is attributed to the rich interface formed between the components and active sites exposed by the defect structure.
文摘The poor electrical conductivity of metal-organic frameworks(MOFs)limits their electrocatalytic performance in the oxygen evolution reaction(OER).In this study,a Py@Co-MOF composite material based on pyrene(Py)molecules and{[Co2(BINDI)(DMA)_(2)]·DMA}_(n)(Co-MOF,H4BINDI=N,N'-bis(5-isophthalic acid)naphthalenediimide,DMA=N,N-dimethylacetamide)was synthesized via a one-pot method,leveragingπ-πinteractions between pyrene and Co-MOF to modulate electrical conductivity.Results demonstrate that the Py@Co-MOF catalyst exhibited significantly enhanced OER performance compared to pure Co-MOF or pyrene-based electrodes,achieving an overpotential of 246 mV at a current density of 10 mA·cm^(-2) along with excellent stability.Density functional theory(DFT)calculations reveal that the formation of O*in the second step is the rate-determining step(RDS)during the OER process on Co-MOF,with an energy barrier of 0.85 eV due to the weak adsorption affinity of the OH*intermediate for Co sites.CCDC:2419276.
基金National MCF Energy R&D Program(2024YFE03260300)。
文摘Refractory metals,including tungsten(W),tantalum(Ta),molybdenum(Mo),and niobium(Nb),play a vital role in industries,such as nuclear energy and aerospace,owing to their exceptional melting temperatures,thermal durability,and corrosion resistance.These metals have body-centered cubic crystal structure,characterized by limited slip systems and impeded dislocation motion,resulting in significant low-temperature brittleness,which poses challenges for the conventional processing.Additive manufacturing technique provides an innovative approach,enabling the production of intricate parts without molds,which significantly improves the efficiency of material usage.This review provides a comprehensive overview of the advancements in additive manufacturing techniques for the production of refractory metals,such as W,Ta,Mo,and Nb,particularly the laser powder bed fusion.In this review,the influence mechanisms of key process parameters(laser power,scan strategy,and powder characteristics)on the evolution of material microstructure,the formation of metallurgical defects,and mechanical properties were discussed.Generally,optimizing powder characteristics,such as sphericity,implementing substrate preheating,and formulating alloying strategies can significantly improve the densification and crack resistance of manufactured parts.Meanwhile,strictly controlling the oxygen impurity content and optimizing the energy density input are also the key factors to achieve the simultaneous improvement in strength and ductility of refractory metals.Although additive manufacturing technique provides an innovative solution for processing refractory metals,critical issues,such as residual stress control,microstructure and performance anisotropy,and process stability,still need to be addressed.This review not only provides a theoretical basis for the additive manufacturing of high-performance refractory metals,but also proposes forward-looking directions for their industrial application.
文摘The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor featuring a broad spectral absorption range,is successfully employed as the electron acceptor to combine with CdS for constructing a S-scheme heterojunction.The optimized photocatalyst(CdSCuO2∶1)delivers an exceptional hydrogen evolution rate of 18.89 mmol/(g·h),4.15-fold higher compared with bare CdS.X-ray photoelectron spectroscopy(XPS)and ultraviolet-visible diffuse reflection absorption spectroscopy(UV-vis DRS)confirmed the S-scheme band structure of the composites.Moreover,the surface photovoltage(SPV)and electron paramagnetic resonance(EPR)indicated that the photogenerated electrons and photogenerated holes of CdS-CuO2∶1 were respectively transferred to the conduction band(CB)of CdS with a higher reduction potential and the valence band(VB)of CuO with a higher oxidation potential under illumination,as expected for the S-scheme mechanism.Density-functional-theory calculations of the electron density difference(EDD)disclose an interfacial electric field oriented from CdS to CuO.This built-in field suppresses charge recombination and accelerates carrier migration,rationalizing the markedly enhanced PHE activity.This study offers a novel strategy for designing S-scheme heterojunctions with high light harvesting and charge utilization toward sustainable solar-tohydrogen conversion.
基金supported by the National Natural Science Foundation of China(U2106216,51971121,52002228,22025108,U21A20327,and 22121001)the National Key R&D Program of China(2022YFA1504500 and 2024YFA1509500)+7 种基金the Major-Special Science and Technology Project in Shandong Province(2023ZLGX05)the Natural Science Foundation of Shandong Province for Major Basic Research Project(ZR2022ZD12)the Qingdao Marine Science and Technology Innovation Project(22-3-3-hygg-27-hy)the Fundamental Research Fund for Central University(202141027)the Key R&D Plan of Shandong Province(2022JMRH0202)the Taishan Scholar of Climbing Plan(tspd20230603)the Taishan Scholar of Youth Plan(tsqn202211072)the Natural Science Foundation of Shandong Province(ZR2024MB065)。
文摘Ruthenium-based materials(Ru and RuO_(2))are promising electrocatalysts toward electrochemical water splitting(EWS)though there are still issues with them that needs to be resolved such as relatively strong adsorption strength of intermediates over Ru and oxidative dissolution of RuO_(2).In this article,an overview of the recent progress and challenges with Ru-based electrocatalysts for EWS is provided.Firstly,fundamentals of EWS are summarized from the aspects of reaction mechanisms and activity descriptors.Next,the typical methods of fabricating Ru-based catalysts are demonstrated mainly including hydrothermal/solvothermal syntheses,organic ligand-assisted syntheses,pyrolysis,acid etching,cation exchange methods and molten salt-assisted syntheses.We then focus on illustrating the enhancing strategies toward creating advanced Ru-based electrocatalysts by demonstrating the typical examples,which include alloying,doping,structure design,interface engineering,single-atom catalyst design,high-entropy alloy design,phase engineering and defecting engineering.In this section,the structureproperty correlation is elucidated aiming to the design of more efficient Ru-based electrocatalysts for EWS.Finally,we conclude the review by addressing the challenges and prospects of electrochemical water splitting and the development of Rubased catalysts.
文摘The large-scale application of water electrolysis for H_(2) production is hindered by the sluggish kinetics of the anodic oxygen evolution reaction(OER).To improve the efficiency of water electrolyzers,numerous efforts have been devoted to developing robust OER catalysts.Among them,Ni-based materials have been identified as state-of-the-art catalysts in alkaline conditions due to their high catalytic activity[1,2].During OER,these catalysts can undergo surface reconstruction and form(oxy)hydroxide species on the surface,which is the real active phase and its chemistry determines the OER performance[3].
基金funded by the National Natural Science Foundation of China(grant no.31670207).
文摘The genus Clematis(Ranunculaceae)comprises over 300 species with remarkable morphological and ecological diversity worldwide.Despite its horticultural,medicinal,and ecological importance,a well-resolved phylogeny and coherent infrageneric classification are still lacking.Here,we reconstruct a robust phylogeny for Clematis using a phylogenomic approach and revise its infrageneric taxonomy.We incorporated 198 samples representing 151 species,two subspecies,and 12 varieties,covering all subgenera and most sections worldwide,obtained from both fresh and herbarium material.Nuclear single nucleotide polymorphisms(SNPs)and complete plastid genomes were assembled for phylogenetic analyses.We also prepared a nuclear ribosomal ITS(nrITS)dataset comprising 171 species,two subspecies,and 12 varieties(217 samples)to include as many species as possible for phylogenetic inference.Phylogenies based on plastid genomes and nrITS exhibited limited resolution and modest support,highlighting challenges in resolving certain relationships.Nuclear SNP analyses yielded a robust phylogenetic tree with 22 well-supported clades corresponding to 22 sections,with most previously recognized subgenera and sections not recovered as monophyletic.Ancestral state reconstruction of 12 key morphological characters revealed multiple independent origins of character states.This study presents the first comprehensive sectional classification for Clematis based on robust phylogenomic evidence,redefines morphological characteristics for each section,and resolves long-standing taxonomic ambiguities.Our results establish a framework for future studies on the evolution,ecology,and horticultural potential of this globally significant genus.
基金support from the National Natural Science Foundation of China(Nos.12305373 and 52276220)the Guangzhou Basic Research Program(No.SL2024A04J00234).
文摘Developing efficient and durable electrocatalysts for acidic oxygen evolution reaction(OER)is pivotal for advancing proton exchange membrane water electrolysis(PEMWEs),yet balancing activity and stability remains a formidable challenge.Herein,we propose a dual-engineering strategy to stabilize Ru-based catalysts by synergizing the oxygen vacancy site-synergized mechanism-lattice oxygen mechanism(OVSM-LOM)with Ru-N bond stabilization.The engineered RuO_(2)@NCC catalyst exhibits exceptional OER performance in 0.5 M H2SO4,achieving an ultralow overpotential of 215 mV at 10 mA cm^(-2) and prolonged stability for over 327 h.The catalyst delivers 300 h of continuous operation at 1 A cm^(-2),with a negligible degradation rate of only 0.067 mV h-1,further demonstrating its potential for practical application.Oxygen vacancies unlock the OVSM-LOM pathway,bypassing the sluggish adsorbate evolution mechanism(AEM)and accelerating reaction kinetics,while the Ru-N bonds suppress Ru dissolution by anchoring low-valent Ru centers.Quasi-in situ X-ray photoelectron spectroscopy(XPS),X-ray absorption spectroscopy(XAS),and isotopic labeling experiments confirm the lattice oxygen participation with *O formation as the rate-determining step.The Ru-N bonds reinforce the structural integrity by stabilizing low-valent Ru centers and inhibiting overoxidation.Theoretical calculations further verify that the synergistic interaction between OVs and Ru-O(N)active sites optimizes the Ru d-band center and stabilizes intermediates,while Ru-N coordination enhances structural integrity.This study establishes a novel paradigm for designing robust acidic OER catalysts through defect and coordination engineering,bridging the gap between activity and stability for sustainable energy technologies.
基金Supported by the National Natural Science Foundation of China(No.32170204)。
文摘This study presents a comprehensive phylogenetic analysis on Batrachospermaceae based on key taxonomic identifiers(rbcL,psaA,psbA,and COI-5P)from some genera.To systematically explore the phylogenetic relationships and taxonomy within Batrachospermaceae,we integrated molecular and morphological data,and explored the phylogeny,character evolution,and ancestral geographical origin and provided a theoretical support for the classification and geographic origination of Batrachospermaceae.Our findings reveal distinct relationships within the phylogenetic tree.Notably,10 genera(Sirodotia,Batrachospermum,Tuomeya,Volatus,Lympha,Nothocladus,Torularia,Sheathia,Nocturama,and Petrohua)are closely associated in the rbcL phylogenetic tree.Additionally,four genera(Kumanoa,Hoefkenia,Notohesperus,and Virescentia)exhibit high support ratios,indicating their close interrelations.Other genera,including Paludicola,Visia,Acarposporophycos,Macrosporophycos,Visioidea,Balliopsis,and Psilosiphon,exhibit clustering traits.Furthermore,the multigene sequences provide a robust support for Montagnia that forms a monophyletic group.Ancestral reconstruction of morphological characters identifies nine primitive character states,including whorl,fascicle length,cortical cells,secondary fascicles,the shape of carpogonical branch,spermatangia,carposporophyte,carpogonium and trichogyne,with Visia likely representing ancestral traits in Batrachospermaceae.Furthermore,geographical origin maps suggest a potential common ancestral of Batrachospermaceae origin in the American continent.Additional to conventional analyses,including evolutionary and ancestral reconstruction investigations into key morphological characters,we attempt to reconstruct the biogeography within the Batrachospermaceae,thus contributing to a nuanced understanding of its origin.
基金Supported by the National Natural Science Foundation of China(No.31970217)the Scientific and Technological Innovation Programs of Higher Education Institution in Shanxi(No.2019L0070)。
文摘Stephanodiscaceae is one of the most diverse family of the freshwater centric diatoms.However,the scarcity of whole plastome data poses a significant challenge to the undertaking of genomic studies on this taxonomic group.We collected data on the plastid genomes from 33 members of the Stephanodiscaceae and its close relatives,including 12 newly-sequenced genomes and 21 deposited in National Center for Biotechnology Information(NCBI).Phylogenetic trees are yielded five major clades based on homologous genes.The features of the plastid genomes,including repeat sequences,codon usage,and selection pressure for each clade,are analyzed.The paper makes a contribution to the field of diatom genomics by describing the structural characteristics of the plastid genomes in the Stephanodiscaceae and its closely related species,complemented by related analyses.It provides crucial data that will serve as indispensable references for future research.
基金supported by the National Natural Science Foundation of China(Grant No.42277147)Ningbo Public Welfare Research Program(Grant No.2024S081)Ningbo Natural Science Foundation(Grant No.2024J186).
文摘Rock brittleness is a critical property in geotechnical and energy engineering,as it directly influences the prediction of rock failure and stability assessment.Although numerous methods have been developed to evaluate brittleness,many fail to comprehensively account for the impacts of microstructural changes,mineralogical characteristics,and stress conditions on energy evolution during failure.This study proposes a novel approach for brittleness evaluation based on the energy evolution throughout the post-peak failure process,integrating two micromechanical mechanisms:crack propagation and frictional sliding.A new brittleness index is defined as the ratio of generated surface energy to released elastic energy,providing a unified framework for assessing both Class I and Class II mechanical behaviors.The brittleness of cyan,white,and gray sandstones was investigated under various confining pressures and moisture conditions using X-ray diffraction(XRD),scanning electron microscopy(SEM),and conventional triaxial compression(CTC)tests.The results demonstrate that brittleness decreases with increasing confining pressure,due to suppressed crack propagation,and increases under saturated conditions,as moisture enhances crack propagation.By establishing connections between mineral composition,microstructural features,and stress-induced responses,the proposed method overcame limitations of previous approaches and offered a more precise tool for evaluating rock brittleness under diverse environmental scenarios.
文摘After billions of years of evolution,biological intelligence has converged on unrivalled energy efficiency and environmental adaptability.The human brain,for instance,is highly efficient in information transmission,consuming only about 20 W onaverage in a resting state[1,2].A key to this efficiency is that biological signal transduction and processing rely significantly on multi-ions as the signal carriers.Inspired by this paradigm.
基金supported partially by the Australian Government through the Australian Research Council Centres of Excellence funding scheme(project CE200100029)。
文摘Background:Tandem gene repeats naturally occur as important genomic features and determine many traits in living organisms,like human diseases and microbial productivities of target bioproducts.Methods:Here,we developed a bacterial type-II toxin-antitoxin-mediated method to manipulate genomic integration of tandem gene repeats in Saccharomyces cerevisiae and further visualised the evolutionary trajectories of gene repeats.We designed a tri-vector system to introduce toxin-antitoxin-driven gene amplification modules.Results:This system delivered multi-copy gene integration in the form of tandem gene repeats spontaneously and independently from toxin-antitoxin-mediated selection.Inducing the toxin(RelE)expressing via a copper(II)-inducible CUP1 promoter successfully drove the in-situ gene amplification of the antitoxin(RelB)module,resulting in~40 copies of a green fluorescence reporter gene per copy of genome.Copy-number changes,copy-number increase and copy-number decrease,and stable maintenance were visualised using the green fluorescence protein and blue chromoprotein AeBlue as reporters.Copy-number increases happened spontaneously and independent on a selection pressure.Increased copy number was quickly enriched through toxin-antitoxin-mediated selection.Conclusion:In summary,the bacterial toxin-antitoxin systems provide a flexible mechanism to manipulate gene copy number in eukaryotic cells and can be exploited for synthetic biology and metabolic engineering applications.
基金supported by the Korea Institute for Advancement of Technology (KIAT)the Ministry of Trade,Industry&Energy (MOTIE) of the Republic of Korea (No. P0022130)by the Institute of Information&Communications Technology Planning&Evaluation(IITP)-Innovative Human Resource Development for Local Intellectualization program grant funded by the Korea government (MSIT)(IITP-2025-RS-2023-00259678)
文摘To realize the practical application of anion exchange membrane water electrolysis(AEMWE),it is essential to develop highly active,durable,and cost-effective electrocatalyst for oxygen evolution reaction(OER).Herein,we report a hollow-structured Ni_(x)Co_(1−x)O/Ni_(3)S_(2)/Co_(9)S_(8)heterostructure synthesized via sequential template-assisted growth,thermal oxidation,and controlled sulfidation process.The abundant bimetallic heterointerfaces not only provide additional active sites but also promote electronic modulation via charge redistribution.Additionally,the porous and hollow architecture enhances active surface area and mass transfer ability,thereby increasing the number of accessible active sites for alkaline OER.As a result,the prepared electrocatalyst achieves low overpotential of 310 mV at 10 mA cm^(−2)and small Tafel slope of 55.94 mV dec^(−1),demonstrating the exceptional electrocatalytic performance for alkaline OER.When integrated as the anode in an AEMWE cell,it delivers outstanding performance with only 1.657 V at 1.0 A cm^(−2)and reaches high current density of 5.0 A cm^(−2)at 1.989 V,surpassing those of commercial RuO_(2).The cell also shows excellent long-term durability over 100 h with minimal degradation.This study highlights the strong potential of rationally engineered oxide/sulfide heterostructures for next-generation alkaline water electrolysis.
基金supported by the National Natural Science Foundation of China (No.52274304)。
文摘Developing catalysts with excellent stability while significantly reducing the overpotential of the oxygen evolution reaction(OER) is crucial for advancing overall water splitting(OWS) systems.In this study,we synthesized the electrode material Ce-NiCo-LDHs@SnO_(2)/NF through a two-step hydrothermal reaction,where Ce-doped NiCo-LDHs are grown on nickel foam modified by a SnO_(2) layer.Ce doping adjusts the internal electronic distribution of Ni Co-LDHs,while the introduction of the SnO_(2) layer enhances electron transfer capability.Together,these factors contribute to the reduction of the OER energy barrier and experimental evidence confirms that the reaction proceeds via the lattice oxygen evolution mechanism(LOM).Consequently,Ce-NiCo-LDHs@SnO_(2)/NF exhibits high level electrochemical performance in OER,requiring only 234 m V overpotential to achieve a current density of 10 m A/cm^(2),with a Tafel slope of just 27.39 m V/dec.When paired with Pt/C/NF,an external potential of only 1.54 V is needed to drive OWS to attain a current density amounting to 10 m A/cm^(2).Furthermore,the catalyst demonstrates stability for 100 h during the OWS stability test.This study underscores the feasibility of enhancing the OER performance through Ce doping and the introduction of a conductive SnO_(2) layer.
基金supported by the National Natural Science Foundation of China(32170571 and 32400451)Hubei Provincial Technological Innovation Plan Project(2025BBB014)+2 种基金the project TowArdsNextGENeration Crops(no.CZ.02.01.01/00/22_008/0004581)of the ERDF Programme Johannes Amos ComeniusProject 2662024JC010 was supported by the Fundamental Research Funds for the Central UniversitiesAdditional funding was provided by the Young Top-notch Talent Cultivation Program of Hubei Province and the Natural Science Foundation of Hubei Province of China(2024AFB116).
文摘Centromeres are indispensable for accurate chromosome segregation,but are subject to rapid sequence turnover while maintaining conserved functions--a paradox in genome evolution.To unravel this paradox,we integrated over 400 fully resolved centromeres from 17 diploid angiosperms spanning 180 million years of divergence,along with 1,000+pan-genomic assemblies,resequencing datasets,and congeneric wholegenome sequences.We showed that angiosperm centromere organization is determined by lineagespecific combinations of satellite repeats and transposable elements(TEs),which,in turn,shape distinct epigenetic landscapes and evolutionary trajectories within centromeres.In particular,TE insertion patterns were found to be key drivers of structural diversification and positional shift of centromeres in angiosperms.Intriguingly,population-level analyses revealed considerable plasticity in centromere sequences across species,with satellite repeats serving as focal points of evolutionary change and exhibiting species-specific heterogeneity patterns.Temporal reconstructions across congeneric species revealed the emergence and subsequent differentiation of centromeric repeats,outlining a dynamic continuum from gradual sequence diversification to complete turnover during speciation,often accompanied by karyotype reorganization.By integrating intra-and inter-species comparisons,we propose a unifying framework in which centromere innovation is governed by a delicate interplay between genome evolution,chromosomal shuffling,and selection constraints,resulting in phylogenomic signatures of centromeredriven speciation.
基金supported by Progetto Trapezio,Compagnia di San Paolo(67935-2021.2174),to LBFondazione CRT(Cassa di Risparmio di Torino,RF=2022.0618),to LBPRIN2022(grant 2022LB4X3N),to LB。
文摘The capacity of the central nervous system for structural plasticity and regeneration is commonly believed to show a decreasing progression from“small and simple”brains to the larger,more complex brains of mammals.However,recent findings revealed that some forms of neural plasticity can show a reverse trend.Although plasticity is a well-preserved,transversal feature across the animal world,a variety of cell populations and mechanisms seem to have evolved to enable structural modifications to take place in widely different brains,likely as adaptations to selective pressures.Increasing evidence now indicates that a trade-off has occurred between regenerative(mostly stem cell–driven)plasticity and developmental(mostly juvenile)remodeling,with the latter primarily aimed not at brain repair but rather at“sculpting”the neural circuits based on experience.In particular,an evolutionary trade-off has occurred between neurogenic processes intended to support the possibility of recruiting new neurons throughout life and the different ways of obtaining new neurons,and between the different brain locations in which plasticity occurs.This review first briefly surveys the different types of plasticity and the complexity of their possible outcomes and then focuses on recent findings showing that the mammalian brain has a stem cell–independent integration of new neurons into pre-existing(mature)neural circuits.This process is still largely unknown but involves neuronal cells that have been blocked in arrested maturation since their embryonic origin(also termed“immature”or“dormant”neurons).These cells can then restart maturation throughout the animal's lifespan to become functional neurons in brain regions,such as the cerebral cortex and amygdala,that are relevant to high-order cognition and emotions.Unlike stem cell–driven postnatal/adult neurogenesis,which significantly decreases from small-brained,short-living species to large-brained ones,immature neurons are particularly abundant in large-brained,long-living mammals,including humans.The immature neural cell populations hosted in these complex brains are an interesting example of an“enlarged road”in the phylogenetic trend of plastic potential decreases commonly observed in the animal world.The topic of dormant neurons that covary with brain size and gyrencephaly represents a prospective turning point in the field of neuroplasticity,with important translational outcomes.These cells can represent a reservoir of undifferentiated neurons,potentially granting plasticity within the high-order circuits subserving the most sophisticated cognitive skills that are important in the growing brains of young,healthy individuals and are frequently affected by debilitating neurodevelopmental and degenerative disorders.
基金supported by the National Natural Science Foundation of China(21831001,21571016,91122028)the National Science Fund for Distinguished Young Scholars(20725101)。
文摘A core-shell type Co_(19)-added polyoxometalate H_(17)Na_(4)Cs_(21)[Co_(19)(μ_(3)-OH)_(12)(A-α-SiW_(10)O_(37))_(6)]·8 Cl·12H_(2)O(1)has been made under hydrothermal conditions guided by the lacunary directing synthetic strategy.Single crystal X-ray diffraction(SXRD)has shown that 19 Co^(2+)are arranged in a flat plane through edge sharing in a mode of 3-4-5-4-3,forming a core-shell type polyanion cluster{Co_(19)(SiW_(10))_6}with a diameter of approximately 2.24 nm.Visible-light-driven photocatalytic hydrogen evolution performance studies have shown that 1 is an efficient heterogeneous water reduction catalyst(WRC)with the H_(2)evolution rate of 2902.5μmol h^(-1)g^(-1).Moreover,the cycle tests indicated that 1 was also a good heterogeneous catalyst.
基金supported in part by the National Science and Technology Council of Republic of China under the contract numbers NSTC 114-2221-E-019-055-MY2NSTC 114-2221-E-019-069.
文摘Cloud data sharing is an important issue in modern times.To maintain the privacy and confidentiality of data stored in the cloud,encryption is an inevitable process before uploading the data.However,the centralized management and transmission latency of the cloud makes it difficult to support real-time processing and distributed access structures.As a result,fog computing and the Internet of Things(IoT)have emerged as crucial applications.Fog-assisted proxy re-encryption is a commonly adopted technique for sharing cloud ciphertexts.It allows a semitrusted proxy to transforma data owner’s ciphertext into another re-encrypted ciphertext intended for a data requester,without compromising any information about the original ciphertext.Yet,the user revocation and cloud ciphertext renewal problems still lack effective and secure mechanisms.Motivated by it,we propose a revocable conditional proxy re-encryption scheme offering ciphertext evolution(R-CPRE-CE).In particular,a periodically updated time key is used to revoke the user’s access privileges while an access condition prevents a malicious proxy from reencrypting unauthorized ciphertext.We also demonstrate that our scheme is provably secure under the notion of indistinguishability against adaptively chosen identity and chosen ciphertext attacks in the random oracle model.Performance analysis shows that our scheme reduces the computation time for a complete data access cycle from an initial query to the final decryption by approximately 47.05%compared to related schemes.
基金funded by the National Natural Science Foundation of China(Nos.52209130 and 52379100)Shandong Provincial Natural Science Foundation(No.ZR2024ME112).
文摘Thermal-mechanical damage and deformation at the interface between shotcrete linings and the surrounding rock of tunnels under high-temperature and variable-temperature conditions are critical to the safe construction and operation of tunnel engineering.This study investigated the thermo-mechanical damage behavior of the composite interface between alkali-resistant glass fiber-reinforced concrete(ARGFRC)and granite,focusing on a plateau railway tunnel.Laboratory triaxial tests,laser scanning,XRD analysis,numerical simulations,and theoretical analyses were employed to investigate how different initial curing temperatures and joint roughness coefficient(JRC)influence interfacial damage behavior.The results indicate that an increase in interface roughness exacerbates the structural damage at the interface.At a JRC of 19.9 and a temperature of 70℃,crack initiation in granite was notably restrained when the confining pressure rose from 7 MPa to 10 MPa.Roughness-induced stress distribution at the interface was notably altered,although this effect became less pronounced under high confining pressure conditions.Additionally,during high-temperature curing,thermal stress concentration at the tips of micro-convex protrusions on the granite surface induced microcracks in the adjacent ARGFRC matrix,followed by deformation.These findings provide practical guidelines for designing concrete support systems to ensure tunnel structural safety in high-altitude regions with harsh thermal environments.
