The exploration of sustainable energy utilization requires the imple-mentation of advanced electrochemical devices for efficient energy conversion and storage,which are enabled by the usage of cost-effective,high-perf...The exploration of sustainable energy utilization requires the imple-mentation of advanced electrochemical devices for efficient energy conversion and storage,which are enabled by the usage of cost-effective,high-performance electro-catalysts.Currently,heterogeneous atomically dispersed catalysts are considered as potential candidates for a wide range of applications.Compared to conventional cata-lysts,atomically dispersed metal atoms in carbon-based catalysts have more unsatu-rated coordination sites,quantum size effect,and strong metal-support interactions,resulting in exceptional catalytic activity.Of these,dual-atomic catalysts(DACs)have attracted extensive attention due to the additional synergistic effect between two adja-cent metal atoms.DACs have the advantages of full active site exposure,high selectiv-ity,theoretical 100%atom utilization,and the ability to break the scaling relationship of adsorption free energy on active sites.In this review,we summarize recent research advancement of DACs,which includes(1)the comprehensive understanding of the synergy between atomic pairs;(2)the synthesis of DACs;(3)characterization meth-ods,especially aberration-corrected scanning transmission electron microscopy and synchrotron spectroscopy;and(4)electrochemical energy-related applications.The last part focuses on great potential for the electrochemical catalysis of energy-related small molecules,such as oxygen reduction reaction,CO_(2) reduction reaction,hydrogen evolution reaction,and N_(2) reduction reaction.The future research challenges and opportunities are also raised in prospective section.展开更多
The surface properties of oxidic supports and their interaction with the supported metals play critical roles in governing the catalytic activities of oxide‐supported metal catalysts.When metals are supported on redu...The surface properties of oxidic supports and their interaction with the supported metals play critical roles in governing the catalytic activities of oxide‐supported metal catalysts.When metals are supported on reducible oxides,dynamic surface reconstruction phenomena,including strong metal–support interaction(SMSI)and oxygen vacancy formation,complicate the determination of the structural–functional relationship at the active sites.Here,we performed a systematic investigation of the dynamic behavior of Au nanocatalysts supported on flame‐synthesized TiO_(2),which takes predominantly a rutile phase,using CO oxidation above room temperature as a probe reaction.Our analysis conclusively elucidated a negative correlation between the catalytic activity of Au/TiO_(2) and the oxygen vacancy at the Au/TiO_(2) interface.Although the reversible formation and retracting of SMSI overlayers have been ubiquitously observed on Au/TiO_(2) samples,the catalytic consequence of SMSI remains inconclusive.Density functional theory suggests that the electron transfer from TiO_(2) to Au is correlated to the presence of the interfacial oxygen vacancies,retarding the catalytic activation of CO oxidation.展开更多
The development of aqueous Zn batteries is limited by parasitic water reactions,corrosion,and dendrite growth.To address these challenges,an inner Helmholtz plane(IHP)regulation method is proposed by employing low-cos...The development of aqueous Zn batteries is limited by parasitic water reactions,corrosion,and dendrite growth.To address these challenges,an inner Helmholtz plane(IHP)regulation method is proposed by employing low-cost,non-toxic maltitol as the electrolyte additive.The preferential adsorption behavior of maltitol can expel the water from the inner Helmholtz plane,and thus hinder the immediate contact between Zn metal and H_(2)O.Meanwhile,strong interaction between maltitol and H_(2)O molecules can restrain the activity of H_(2)O.Besides,the"IHP adsorption effect"along with the low LUMO energy level of maltitol-CF_(3)SO_(3)^(-)can promote the in-situ formation of an organic-inorganic complex solid electrolyte interface(SEI)layer.As a result,the hydrogen/oxygen evolution side reaction,corrosion,and dendrites issues are effectively suppressed,thereby leading to highly reversible and dendrite-free Zn plating/stripping.The Zn‖I_(2)battery with hybrid electrolytes also demonstrates high electrochemical performance and ultralong cycling stability,showing a capacity retention of 75%over 20000 charge-discharge cycles at a large current density of 5 A g^(-1).In addition,the capacity of the device has almost no obvious decay over20000 cycles even at-30℃.This work offers a successful electrolyte regulation strategy via the IHP adsorption effect to design electrolytes for high-performance rechargeable Zn-ion batteries.展开更多
The Internet of Things(IoT)is a network system that connects physical devices through the Internet,allowing them to interact.Nowadays,IoT has become an integral part of our lives,offering convenience and smart functio...The Internet of Things(IoT)is a network system that connects physical devices through the Internet,allowing them to interact.Nowadays,IoT has become an integral part of our lives,offering convenience and smart functionality.However,the growing number of IoT devices has brought about a corresponding increase in cybersecurity threats,such as device vulnerabilities,data privacy concerns,and network susceptibilities.Integrating blockchain technology with IoT has proven to be a promising approach to enhance IoT security.Nevertheless,the emergence of quantum computing poses a significant challenge to the security of traditional classical cryptography used in blockchain,potentially exposing it to quantum cyber-attacks.To support the growth of the IoT industry,mitigate quantum threats,and safeguard IoT data,this study proposes a robust blockchain solution for IoT that incorporates both classical and post-quantum security measures.Firstly,we present the Quantum-Enhanced Blockchain Architecture for IoT(QBIoT)to ensure secure data sharing and integrity protection.Secondly,we propose an improved Proof of Authority consensus algorithm called“Proof of Authority with Random Election”(PoARE),implemented within QBIoT for leader selection and new block creation.Thirdly,we develop a publickey quantum signature protocol for transaction verification in the blockchain.Finally,a comprehensive security analysis of QBIoT demonstrates its resilience against cyber threats from both classical and quantum adversaries.In summary,this research introduces an innovative quantum-enhanced blockchain solution to address quantum security concernswithin the realmof IoT.The proposedQBIoT framework contributes to the ongoing development of quantum blockchain technology and offers valuable insights for future research on IoT security.展开更多
BACKGROUND Lymph node ratio(LNR)was demonstrated to play a crucial role in the prognosis of many tumors.However,research concerning the prognostic value of LNR in postoperative gastric neuroendocrine neoplasm(NEN)pati...BACKGROUND Lymph node ratio(LNR)was demonstrated to play a crucial role in the prognosis of many tumors.However,research concerning the prognostic value of LNR in postoperative gastric neuroendocrine neoplasm(NEN)patients was limited.AIM To explore the prognostic value of LNR in postoperative gastric NEN patients and to combine LNR to develop prognostic models.METHODS A total of 286 patients from the Surveillance,Epidemiology,and End Results database were divided into the training set and validation set at a ratio of 8:2.92 patients from the First Affiliated Hospital of Soochow University in China were designated as a test set.Cox regression analysis was used to explore the relationship between LNR and disease-specific survival(DSS)of gastric NEN patients.Random survival forest(RSF)algorithm and Cox proportional hazards(CoxPH)analysis were applied to develop models to predict DSS respectively,and compared with the 8th edition American Joint Committee on Cancer(AJCC)tumornode-metastasis(TNM)staging.RESULTS Multivariate analyses indicated that LNR was an independent prognostic factor for postoperative gastric NEN patients and a higher LNR was accompanied by a higher risk of death.The RSF model exhibited the best performance in predicting DSS,with the C-index in the test set being 0.769[95%confidence interval(CI):0.691-0.846]outperforming the CoxPH model(0.744,95%CI:0.665-0.822)and the 8th edition AJCC TNM staging(0.723,95%CI:0.613-0.833).The calibration curves and decision curve analysis(DCA)demonstrated the RSF model had good calibration and clinical benefits.Furthermore,the RSF model could perform risk stratification and individual prognosis prediction effectively.CONCLUSION A higher LNR indicated a lower DSS in postoperative gastric NEN patients.The RSF model outperformed the CoxPH model and the 8th edition AJCC TNM staging in the test set,showing potential in clinical practice.展开更多
Remote-sensing measurements indicate that heavy ions in the corona undergo an anisotropic and mass-charge dependent energization.A popular explanation to this phenomenon is the damping of the Alfven/ion cyclotron wave...Remote-sensing measurements indicate that heavy ions in the corona undergo an anisotropic and mass-charge dependent energization.A popular explanation to this phenomenon is the damping of the Alfven/ion cyclotron waves.In this paper,we propose that the ion beam instability can be an important source of the Alfven/ion cyclotron waves,and we study the excitation of the ion beam instability in the corona at the heliocentric distance~3R_(⊙)and the corresponding energy transfer process therein ba sed on plasma kinetic theory.The results indicate that the existence of the motionless heavy ions inhibits the ion beam instability.However,the anisotropic beams of heavy ions promote the excitation of the ion beam instability.Besides,the existence ofαbeams can provide a second energy source for exciting beam instability.However,when both the proton beam and the a beam reach the instability excitation threshold,the proton beam driven instability excites preferentially.Moreover,the excitation threshold of the Alfven/ion cyclotron instability driven by ion beam is of the local Alfven speed or even less in the corona.展开更多
Single atomic catalysts(SACs),especially metal-nitrogen doped carbon(M-NC)catalysts,have been extensively explored for the electrochemical oxygen reduction reaction(ORR),owing to their high activity and atomic utiliza...Single atomic catalysts(SACs),especially metal-nitrogen doped carbon(M-NC)catalysts,have been extensively explored for the electrochemical oxygen reduction reaction(ORR),owing to their high activity and atomic utilization efficiency.However,there is still a lack of systematic screening and optimization of local structures surrounding active centers of SACs for ORR as the local coordination has an essential impact on their electronic structures and catalytic performance.Herein,we systematic study the ORR catalytic performance of M-NC SACs with different central metals and environmental atoms in the first and second coordination sphere by using density functional theory(DFT)calculation and machine learning(ML).The geometric and electronic informed overpotential model(GEIOM)based on random forest algorithm showed the highest accuracy,and its R^(2) and root mean square errors(RMSE)were 0.96 and 0.21,respectively.30 potential high-performance catalysts were screened out by GEIOM,and the RMSE of the predicted result was only 0.12 V.This work not only helps us fast screen high-performance catalysts,but also provides a low-cost way to improve the accuracy of ML models.展开更多
Radon is recognized as a powerful tracer of certain geophysical processes in marine and aquatic environments.In the past few decades,the instruments and methods for measuring radon concentration in water have been dev...Radon is recognized as a powerful tracer of certain geophysical processes in marine and aquatic environments.In the past few decades,the instruments and methods for measuring radon concentration in water have been developed to some extent but still lack underwater in-situ measurements.Here we present an in-situ detection equipment for radon-in-water(pulsed ionization chamber(PIC)-radon)to measure dissolved radon in ocean and groundwater settings.The equipment has been successfully deployed in the Jiaozhou Bay in July 2022 and has achieved 14 d of unattended underwater in-situ observation.Then it was successfully placed in a groundwater monitoring well in the Laizhou Bay in November 2022 and monitored radon activities for over 30 d.The results showed that this instrument had a good indication of submarine groundwater discharge.The PIC-radon detector takes advantage of smaller size,lower power consumption,and is barely influenced by humidity,making it particularly suitable for long-term in-situ measurement,especially in harsh environments with limited human care or deployment spaces.展开更多
Radon(Rn)is a naturally occurring radioactive inert gas in nature,and^(222)Rn has been routinely used as a powerful tracer in various aquatic environmental research on timescales of hours to days,such as submarine gro...Radon(Rn)is a naturally occurring radioactive inert gas in nature,and^(222)Rn has been routinely used as a powerful tracer in various aquatic environmental research on timescales of hours to days,such as submarine groundwater discharge.Here we developed a new approach to measure^(222)Rn in discrete water samples with a wide range of^(222)Rn concentrations using a Pulsed Ionization Chamber(PIC)Radon Detector.The sensitivity of the new PIC system is evaluated at 6.06 counts per minute for 1 Bq/L when a 500 mL water sample volume is used.A robust logarithmic correlation between sample volumes,ranging from 250 mL to 5000 mL,and system sensitivity obtained in this study strongly suggests that this approach is suitable for measuring radon concentration levels in various natural waters.Compared to the currently available methods for measuring radon in grab samples,the PIC system is cheaper,easier to operate and does not require extra accessories(e.g.,drying tubes etc.)to maintain stable measurements throughout the counting procedure.展开更多
When simulating the process from elastic–plastic deformation,damage to failure in a metal structure collision,it is necessary to use the large shell element due to the calculation efficiency,but this would affect the...When simulating the process from elastic–plastic deformation,damage to failure in a metal structure collision,it is necessary to use the large shell element due to the calculation efficiency,but this would affect the accuracy of damage evolution simulation.The compensation algorithm adjusting failure strain according to element size is usually used in the damage model to deal with the problem.In this paper,a new nonlinear compensation algorithm between failure strain and element size was proposed,which was incorporated in the damage model GISSMO(Generalized incremental stress state dependent damage model)to characterize ductile fracture.And associated material parameters were calibrated based on tensile experiments of aluminum alloy specimens with notches.Simulation and experimental results show that the new compensation algorithm significantly reduces the dependence of element size compared with the constant failure strain model and the damage model with the linear compensation algorithm.During the axial splitting process of a circular tubular structure,the new compensation algorithm keeps the failure prediction errors low over the stress states ranging from shear to biaxial tension,and achieves the objective prediction of the damage evolution process.This study demonstrates how the compensation algorithm resolves the contradiction between large element size and fracture prediction accuracy,and this facilitates the use of the damage model in ductile fracture prediction for engineering structures.展开更多
The high-rate cyclability of Li-rich Mn-based oxide(LMO)is highly limited by the electrochemical polarization resulting from the slow kinetic of the Li2MnO3 phase.Herein,the Prussian blue(PB)coating layer with specifi...The high-rate cyclability of Li-rich Mn-based oxide(LMO)is highly limited by the electrochemical polarization resulting from the slow kinetic of the Li2MnO3 phase.Herein,the Prussian blue(PB)coating layer with specific redox potential is introduced as a functionalized interface to overcome the side effect and the escaping of O on the surface of LMO,especially its poor rate capability.In detail,the PB layer can restrict the large polarization of LMO by sharing overloaded current at a high rate due to the synchronous redox of PB and LMO.Consequently,an enhanced high rate performance with capacity retention of 87.8%over 300 cycles is obtained,which is superior to 50.5%of the pristine electrode.Such strategies on the high-rate cyclability of Li-rich Mn-based oxide compatible with good low-rate performances may attract great attention for pursuing durable performances.展开更多
BACKGROUND Longus colli tendinitis(LCT)with dyspnea is a relatively less-reported condition in the literature,and physicians should be aware of its existence.Misdiagnosis of this condition may cause unnecessary treatm...BACKGROUND Longus colli tendinitis(LCT)with dyspnea is a relatively less-reported condition in the literature,and physicians should be aware of its existence.Misdiagnosis of this condition may cause unnecessary treatment for dyspnea.CASE SUMMARY Herein,we report the case of a 40-year-old man with acute neck tendonitis.The patient presented to the pneumology department clinic with a complaint of acute neck tendonitis with dyspnea.An emergency cervical magnetic resonance examination was performed,and the preliminary diagnosis was“acute longus cervicalis tendinitis.”After aggressive medical treatment,the symptoms obviously improved.CONCLUSION LCT is a self-limiting disease that usually improves after three to seven days of conservative treatment following a definite diagnosis.However,owing to its insidious onset and complex clinical manifestations,most relevant personnel are not fully understood.The definite diagnosis of LCT is based on a comprehensive understanding of the triad,rare symptoms,and the clear identification of cervical 1 and 2 levels calcification and prevertebral edema by medical imaging examination,especially magnetic resonance imaging and computed tomography.展开更多
How ions evolve in the Earth’s ion foreshock is a basic problem in the heliosphere community,and the ion beam instability is usually proposed to be one major mechanism affecting the ion dynamics therein.This work wil...How ions evolve in the Earth’s ion foreshock is a basic problem in the heliosphere community,and the ion beam instability is usually proposed to be one major mechanism affecting the ion dynamics therein.This work will perform comprehensive analyses of the oblique ion beam instability in the Earth’s ion foreshock.We show that in addition to two well-known parallel instabilities (i.e.,the parallel fast-magnetosonic whistler instability and the parallel Alfvén ion cyclotron instability),the oblique Alfvén ion beam (OA/IB) instability can also be triggered by free energy relating to the relative drift d V between the solar wind proton and reflected proton populations.For slow d V (e.g.,d V■2.2V_(A),where VAdenotes the Alfvén speed),it only triggers the OA/IB instability.When d V■2.2V_(A),the growth rate in the OA/IB instability can be about 0.6 times the maximum growth rate in parallel instabilities.Moreover,this work finds the existence of two types of OA/IB instabilities.The first one appears at slow d V and in the small wavenumber region at fast d V,and this instability can be described by the cold fluid model.The second one arises in large wavenumber regions at fast d V,and this instability only appears in warm plasmas.Furthermore,through the energy transfer rate method,we propose that the OA/IB instability is driven by the competition among the Landau and cyclotron wave-particle interactions of beam protons,the cyclotron wave-particle interaction of core protons,and the Landau wave-particle interaction of electrons.Because oblique waves can experience significant damping,the importance of the OA/IB instability may be the effective heating of ions in the Earth’s foreshock.展开更多
The advent of antiproliferative drug-eluting vascular stents can dramatically reduce in-stent restenosis via inhibiting the hyperproliferation of vascular smooth muscle cells.However,the antiproliferative drugs also r...The advent of antiproliferative drug-eluting vascular stents can dramatically reduce in-stent restenosis via inhibiting the hyperproliferation of vascular smooth muscle cells.However,the antiproliferative drugs also restrain the repair of the injured endothelial layer,which in turn leads to the very later in-stent restenosis.Evidence points that competent endothelium plays a critical role in guaranteeing the long-term patency via maintaining vascular homeostasis.Boosting the regeneration of endothelium on the implanted vascular stents could be rendered as a promising strategy to reduce stent implantation complications.In this regard,bioactive zinc(II)metal-organic framework modified with endothelial cell-targeting Arg-Glu-Asp-Val peptide was embedded in poly(lactide-co-caprolactone)to serve as a functional coating on the surface of titanium substrate,which can promote the proliferation and migration of endothelial cells.The in vitro cell experiments revealed that the zinc(II)metal-organic framework embedded in the polymer coating was able to modulate the behaviors of endothelial cells owing to the bioactive effects of zinc ion and peptide.Our results confirmed that zinc(II)metal-organic framework eluting coating represented a new possibility for promoting the repair of the damaged endothelium with potential clinical implications in vascular-related biomaterials and tissue engineering applications.展开更多
基金This work was supported by the National Natural Science Foundation of China(No.22273065 and No.21673158)Science&Technology Commission of Shanghai Municipality(14DZ2261100).
基金This work was financially supported by the National Key Research and Development Program of China(2018YFA0702002)the Beijing Natural Science Foundation(Z210016)+1 种基金the National Natural Science Foundation of China(51967020,21935001)Shanxi Energy Internet Research Institute(SXEI 2023A004).
文摘The exploration of sustainable energy utilization requires the imple-mentation of advanced electrochemical devices for efficient energy conversion and storage,which are enabled by the usage of cost-effective,high-performance electro-catalysts.Currently,heterogeneous atomically dispersed catalysts are considered as potential candidates for a wide range of applications.Compared to conventional cata-lysts,atomically dispersed metal atoms in carbon-based catalysts have more unsatu-rated coordination sites,quantum size effect,and strong metal-support interactions,resulting in exceptional catalytic activity.Of these,dual-atomic catalysts(DACs)have attracted extensive attention due to the additional synergistic effect between two adja-cent metal atoms.DACs have the advantages of full active site exposure,high selectiv-ity,theoretical 100%atom utilization,and the ability to break the scaling relationship of adsorption free energy on active sites.In this review,we summarize recent research advancement of DACs,which includes(1)the comprehensive understanding of the synergy between atomic pairs;(2)the synthesis of DACs;(3)characterization meth-ods,especially aberration-corrected scanning transmission electron microscopy and synchrotron spectroscopy;and(4)electrochemical energy-related applications.The last part focuses on great potential for the electrochemical catalysis of energy-related small molecules,such as oxygen reduction reaction,CO_(2) reduction reaction,hydrogen evolution reaction,and N_(2) reduction reaction.The future research challenges and opportunities are also raised in prospective section.
基金Science and Technology Innovation Program of Hunan Province,Grant/Award Numbers:2020GK2070,2021RC4006Innovation‐Driven Project of Central South University,Grant/Award Number:2020CX008+3 种基金China Scholarship Council(CSC)National Key R&D Program of China,Grant/Award Number:2022YFE0105900National Natural Science Foundation of China,Grant/Award Number:52276093National Research Foundation Singapore,Grant/Award Number:CREATE。
文摘The surface properties of oxidic supports and their interaction with the supported metals play critical roles in governing the catalytic activities of oxide‐supported metal catalysts.When metals are supported on reducible oxides,dynamic surface reconstruction phenomena,including strong metal–support interaction(SMSI)and oxygen vacancy formation,complicate the determination of the structural–functional relationship at the active sites.Here,we performed a systematic investigation of the dynamic behavior of Au nanocatalysts supported on flame‐synthesized TiO_(2),which takes predominantly a rutile phase,using CO oxidation above room temperature as a probe reaction.Our analysis conclusively elucidated a negative correlation between the catalytic activity of Au/TiO_(2) and the oxygen vacancy at the Au/TiO_(2) interface.Although the reversible formation and retracting of SMSI overlayers have been ubiquitously observed on Au/TiO_(2) samples,the catalytic consequence of SMSI remains inconclusive.Density functional theory suggests that the electron transfer from TiO_(2) to Au is correlated to the presence of the interfacial oxygen vacancies,retarding the catalytic activation of CO oxidation.
基金supported by the National Natural Science Foundation of China(52261160384)the Shenzhen Science and Technology Innovation Commission(RCYX20221008092934093)+1 种基金the Shenzhen Science and Technology Program(KJZD20230923114107014)the support from Testing Technology Center of Materials and Devices,Tsinghua Shenzhen International Graduate School。
文摘The development of aqueous Zn batteries is limited by parasitic water reactions,corrosion,and dendrite growth.To address these challenges,an inner Helmholtz plane(IHP)regulation method is proposed by employing low-cost,non-toxic maltitol as the electrolyte additive.The preferential adsorption behavior of maltitol can expel the water from the inner Helmholtz plane,and thus hinder the immediate contact between Zn metal and H_(2)O.Meanwhile,strong interaction between maltitol and H_(2)O molecules can restrain the activity of H_(2)O.Besides,the"IHP adsorption effect"along with the low LUMO energy level of maltitol-CF_(3)SO_(3)^(-)can promote the in-situ formation of an organic-inorganic complex solid electrolyte interface(SEI)layer.As a result,the hydrogen/oxygen evolution side reaction,corrosion,and dendrites issues are effectively suppressed,thereby leading to highly reversible and dendrite-free Zn plating/stripping.The Zn‖I_(2)battery with hybrid electrolytes also demonstrates high electrochemical performance and ultralong cycling stability,showing a capacity retention of 75%over 20000 charge-discharge cycles at a large current density of 5 A g^(-1).In addition,the capacity of the device has almost no obvious decay over20000 cycles even at-30℃.This work offers a successful electrolyte regulation strategy via the IHP adsorption effect to design electrolytes for high-performance rechargeable Zn-ion batteries.
基金supported by National Key RD Program of China(Grant No.2022YFB3104402,the Research on Digital Identity Trust System for Massive Heterogeneous Terminals in Road Traffic System)the Fundamental Research Funds for the Central Universities(Grant Nos.3282023015,3282023035,3282023051)National First-Class Discipline Construction Project of Beijing Electronic Science and Technology Institute(No.3201012).
文摘The Internet of Things(IoT)is a network system that connects physical devices through the Internet,allowing them to interact.Nowadays,IoT has become an integral part of our lives,offering convenience and smart functionality.However,the growing number of IoT devices has brought about a corresponding increase in cybersecurity threats,such as device vulnerabilities,data privacy concerns,and network susceptibilities.Integrating blockchain technology with IoT has proven to be a promising approach to enhance IoT security.Nevertheless,the emergence of quantum computing poses a significant challenge to the security of traditional classical cryptography used in blockchain,potentially exposing it to quantum cyber-attacks.To support the growth of the IoT industry,mitigate quantum threats,and safeguard IoT data,this study proposes a robust blockchain solution for IoT that incorporates both classical and post-quantum security measures.Firstly,we present the Quantum-Enhanced Blockchain Architecture for IoT(QBIoT)to ensure secure data sharing and integrity protection.Secondly,we propose an improved Proof of Authority consensus algorithm called“Proof of Authority with Random Election”(PoARE),implemented within QBIoT for leader selection and new block creation.Thirdly,we develop a publickey quantum signature protocol for transaction verification in the blockchain.Finally,a comprehensive security analysis of QBIoT demonstrates its resilience against cyber threats from both classical and quantum adversaries.In summary,this research introduces an innovative quantum-enhanced blockchain solution to address quantum security concernswithin the realmof IoT.The proposedQBIoT framework contributes to the ongoing development of quantum blockchain technology and offers valuable insights for future research on IoT security.
基金Supported by the Science and Technology Plan of Suzhou City,No.SKY2021038.
文摘BACKGROUND Lymph node ratio(LNR)was demonstrated to play a crucial role in the prognosis of many tumors.However,research concerning the prognostic value of LNR in postoperative gastric neuroendocrine neoplasm(NEN)patients was limited.AIM To explore the prognostic value of LNR in postoperative gastric NEN patients and to combine LNR to develop prognostic models.METHODS A total of 286 patients from the Surveillance,Epidemiology,and End Results database were divided into the training set and validation set at a ratio of 8:2.92 patients from the First Affiliated Hospital of Soochow University in China were designated as a test set.Cox regression analysis was used to explore the relationship between LNR and disease-specific survival(DSS)of gastric NEN patients.Random survival forest(RSF)algorithm and Cox proportional hazards(CoxPH)analysis were applied to develop models to predict DSS respectively,and compared with the 8th edition American Joint Committee on Cancer(AJCC)tumornode-metastasis(TNM)staging.RESULTS Multivariate analyses indicated that LNR was an independent prognostic factor for postoperative gastric NEN patients and a higher LNR was accompanied by a higher risk of death.The RSF model exhibited the best performance in predicting DSS,with the C-index in the test set being 0.769[95%confidence interval(CI):0.691-0.846]outperforming the CoxPH model(0.744,95%CI:0.665-0.822)and the 8th edition AJCC TNM staging(0.723,95%CI:0.613-0.833).The calibration curves and decision curve analysis(DCA)demonstrated the RSF model had good calibration and clinical benefits.Furthermore,the RSF model could perform risk stratification and individual prognosis prediction effectively.CONCLUSION A higher LNR indicated a lower DSS in postoperative gastric NEN patients.The RSF model outperformed the CoxPH model and the 8th edition AJCC TNM staging in the test set,showing potential in clinical practice.
基金funded by the National Natural Science Foundation of China(NSFC)under No.12347166。
文摘Remote-sensing measurements indicate that heavy ions in the corona undergo an anisotropic and mass-charge dependent energization.A popular explanation to this phenomenon is the damping of the Alfven/ion cyclotron waves.In this paper,we propose that the ion beam instability can be an important source of the Alfven/ion cyclotron waves,and we study the excitation of the ion beam instability in the corona at the heliocentric distance~3R_(⊙)and the corresponding energy transfer process therein ba sed on plasma kinetic theory.The results indicate that the existence of the motionless heavy ions inhibits the ion beam instability.However,the anisotropic beams of heavy ions promote the excitation of the ion beam instability.Besides,the existence ofαbeams can provide a second energy source for exciting beam instability.However,when both the proton beam and the a beam reach the instability excitation threshold,the proton beam driven instability excites preferentially.Moreover,the excitation threshold of the Alfven/ion cyclotron instability driven by ion beam is of the local Alfven speed or even less in the corona.
基金financially supported by the National Key Research and Development Program of China (2018YFA0702002)the Beijing Natural Science Foundation (Z210016)the National Natural Science Foundation of China (21935001)。
文摘Single atomic catalysts(SACs),especially metal-nitrogen doped carbon(M-NC)catalysts,have been extensively explored for the electrochemical oxygen reduction reaction(ORR),owing to their high activity and atomic utilization efficiency.However,there is still a lack of systematic screening and optimization of local structures surrounding active centers of SACs for ORR as the local coordination has an essential impact on their electronic structures and catalytic performance.Herein,we systematic study the ORR catalytic performance of M-NC SACs with different central metals and environmental atoms in the first and second coordination sphere by using density functional theory(DFT)calculation and machine learning(ML).The geometric and electronic informed overpotential model(GEIOM)based on random forest algorithm showed the highest accuracy,and its R^(2) and root mean square errors(RMSE)were 0.96 and 0.21,respectively.30 potential high-performance catalysts were screened out by GEIOM,and the RMSE of the predicted result was only 0.12 V.This work not only helps us fast screen high-performance catalysts,but also provides a low-cost way to improve the accuracy of ML models.
基金The National Natural Science Foundation of China under contract Nos U22A20580 and 42130410the Fundamental Research Funds for the Central Universities under contract No.202341002the Pilot Project for the Integration of Science,Education,and Industry under contract No.2022PY069.
文摘Radon is recognized as a powerful tracer of certain geophysical processes in marine and aquatic environments.In the past few decades,the instruments and methods for measuring radon concentration in water have been developed to some extent but still lack underwater in-situ measurements.Here we present an in-situ detection equipment for radon-in-water(pulsed ionization chamber(PIC)-radon)to measure dissolved radon in ocean and groundwater settings.The equipment has been successfully deployed in the Jiaozhou Bay in July 2022 and has achieved 14 d of unattended underwater in-situ observation.Then it was successfully placed in a groundwater monitoring well in the Laizhou Bay in November 2022 and monitored radon activities for over 30 d.The results showed that this instrument had a good indication of submarine groundwater discharge.The PIC-radon detector takes advantage of smaller size,lower power consumption,and is barely influenced by humidity,making it particularly suitable for long-term in-situ measurement,especially in harsh environments with limited human care or deployment spaces.
基金The National Natural Science Foundation of China under contract Nos 42130410,41876075 and U1906210the Fundamental Research Funds for the Central Universities under contract No.201962003.
文摘Radon(Rn)is a naturally occurring radioactive inert gas in nature,and^(222)Rn has been routinely used as a powerful tracer in various aquatic environmental research on timescales of hours to days,such as submarine groundwater discharge.Here we developed a new approach to measure^(222)Rn in discrete water samples with a wide range of^(222)Rn concentrations using a Pulsed Ionization Chamber(PIC)Radon Detector.The sensitivity of the new PIC system is evaluated at 6.06 counts per minute for 1 Bq/L when a 500 mL water sample volume is used.A robust logarithmic correlation between sample volumes,ranging from 250 mL to 5000 mL,and system sensitivity obtained in this study strongly suggests that this approach is suitable for measuring radon concentration levels in various natural waters.Compared to the currently available methods for measuring radon in grab samples,the PIC system is cheaper,easier to operate and does not require extra accessories(e.g.,drying tubes etc.)to maintain stable measurements throughout the counting procedure.
基金National Natural Science Foundation of China(Grant No.52172353)。
文摘When simulating the process from elastic–plastic deformation,damage to failure in a metal structure collision,it is necessary to use the large shell element due to the calculation efficiency,but this would affect the accuracy of damage evolution simulation.The compensation algorithm adjusting failure strain according to element size is usually used in the damage model to deal with the problem.In this paper,a new nonlinear compensation algorithm between failure strain and element size was proposed,which was incorporated in the damage model GISSMO(Generalized incremental stress state dependent damage model)to characterize ductile fracture.And associated material parameters were calibrated based on tensile experiments of aluminum alloy specimens with notches.Simulation and experimental results show that the new compensation algorithm significantly reduces the dependence of element size compared with the constant failure strain model and the damage model with the linear compensation algorithm.During the axial splitting process of a circular tubular structure,the new compensation algorithm keeps the failure prediction errors low over the stress states ranging from shear to biaxial tension,and achieves the objective prediction of the damage evolution process.This study demonstrates how the compensation algorithm resolves the contradiction between large element size and fracture prediction accuracy,and this facilitates the use of the damage model in ductile fracture prediction for engineering structures.
基金supported by the National Natural Science Foundation of China (51802261,52072298,and 52172228)the Natural Science Foundation of Shaanxi (2019GHJD-13 and 2020JC-41)+2 种基金the Natural Science Basic Research Plan in Shaanxi province of China (2019JLP-04)Xi'an Science and Technology Project of China (2019219714SYS012CG034)the foundation of National Key Laboratory (6142808200202),PR China.
文摘The high-rate cyclability of Li-rich Mn-based oxide(LMO)is highly limited by the electrochemical polarization resulting from the slow kinetic of the Li2MnO3 phase.Herein,the Prussian blue(PB)coating layer with specific redox potential is introduced as a functionalized interface to overcome the side effect and the escaping of O on the surface of LMO,especially its poor rate capability.In detail,the PB layer can restrict the large polarization of LMO by sharing overloaded current at a high rate due to the synchronous redox of PB and LMO.Consequently,an enhanced high rate performance with capacity retention of 87.8%over 300 cycles is obtained,which is superior to 50.5%of the pristine electrode.Such strategies on the high-rate cyclability of Li-rich Mn-based oxide compatible with good low-rate performances may attract great attention for pursuing durable performances.
文摘BACKGROUND Longus colli tendinitis(LCT)with dyspnea is a relatively less-reported condition in the literature,and physicians should be aware of its existence.Misdiagnosis of this condition may cause unnecessary treatment for dyspnea.CASE SUMMARY Herein,we report the case of a 40-year-old man with acute neck tendonitis.The patient presented to the pneumology department clinic with a complaint of acute neck tendonitis with dyspnea.An emergency cervical magnetic resonance examination was performed,and the preliminary diagnosis was“acute longus cervicalis tendinitis.”After aggressive medical treatment,the symptoms obviously improved.CONCLUSION LCT is a self-limiting disease that usually improves after three to seven days of conservative treatment following a definite diagnosis.However,owing to its insidious onset and complex clinical manifestations,most relevant personnel are not fully understood.The definite diagnosis of LCT is based on a comprehensive understanding of the triad,rare symptoms,and the clear identification of cervical 1 and 2 levels calcification and prevertebral edema by medical imaging examination,especially magnetic resonance imaging and computed tomography.
基金supported by the National Key R&D Program of China 2021YFA1600502(2021YFA1600500)the NSFC 41974203。
文摘How ions evolve in the Earth’s ion foreshock is a basic problem in the heliosphere community,and the ion beam instability is usually proposed to be one major mechanism affecting the ion dynamics therein.This work will perform comprehensive analyses of the oblique ion beam instability in the Earth’s ion foreshock.We show that in addition to two well-known parallel instabilities (i.e.,the parallel fast-magnetosonic whistler instability and the parallel Alfvén ion cyclotron instability),the oblique Alfvén ion beam (OA/IB) instability can also be triggered by free energy relating to the relative drift d V between the solar wind proton and reflected proton populations.For slow d V (e.g.,d V■2.2V_(A),where VAdenotes the Alfvén speed),it only triggers the OA/IB instability.When d V■2.2V_(A),the growth rate in the OA/IB instability can be about 0.6 times the maximum growth rate in parallel instabilities.Moreover,this work finds the existence of two types of OA/IB instabilities.The first one appears at slow d V and in the small wavenumber region at fast d V,and this instability can be described by the cold fluid model.The second one arises in large wavenumber regions at fast d V,and this instability only appears in warm plasmas.Furthermore,through the energy transfer rate method,we propose that the OA/IB instability is driven by the competition among the Landau and cyclotron wave-particle interactions of beam protons,the cyclotron wave-particle interaction of core protons,and the Landau wave-particle interaction of electrons.Because oblique waves can experience significant damping,the importance of the OA/IB instability may be the effective heating of ions in the Earth’s foreshock.
基金supported by National Natural Science Foundation of China (Grant No.52373151).
文摘The advent of antiproliferative drug-eluting vascular stents can dramatically reduce in-stent restenosis via inhibiting the hyperproliferation of vascular smooth muscle cells.However,the antiproliferative drugs also restrain the repair of the injured endothelial layer,which in turn leads to the very later in-stent restenosis.Evidence points that competent endothelium plays a critical role in guaranteeing the long-term patency via maintaining vascular homeostasis.Boosting the regeneration of endothelium on the implanted vascular stents could be rendered as a promising strategy to reduce stent implantation complications.In this regard,bioactive zinc(II)metal-organic framework modified with endothelial cell-targeting Arg-Glu-Asp-Val peptide was embedded in poly(lactide-co-caprolactone)to serve as a functional coating on the surface of titanium substrate,which can promote the proliferation and migration of endothelial cells.The in vitro cell experiments revealed that the zinc(II)metal-organic framework embedded in the polymer coating was able to modulate the behaviors of endothelial cells owing to the bioactive effects of zinc ion and peptide.Our results confirmed that zinc(II)metal-organic framework eluting coating represented a new possibility for promoting the repair of the damaged endothelium with potential clinical implications in vascular-related biomaterials and tissue engineering applications.
