Quantum correlation shows a fascinating nature of quantum mechanics and plays an important role in some physics topics,especially in the field of quantum information.Quantum correlations of the composite system can be...Quantum correlation shows a fascinating nature of quantum mechanics and plays an important role in some physics topics,especially in the field of quantum information.Quantum correlations of the composite system can be quantified by resorting to geometric or entropy methods,and all these quantification methods exhibit the peculiar freezing phenomenon.The challenge is to find the characteristics of the quantum states that generate the freezing phenomenon,rather than only study the conditions which generate this phenomenon under a certain quantum system.In essence,this is a classification problem.Machine learning has become an effective method for researchers to study classification and feature generation.In this work,we prove that the machine learning can solve the problem of X form quantum states,which is a problem of physical significance.Subsequently,we apply the density-based spatial clustering of applications with noise(DBSCAN)algorithm and the decision tree to divide quantum states into two different groups.Our goal is to classify the quantum correlations of quantum states into two classes:one is the quantum correlation with freezing phenomenon for both Rènyi discord(α=2)and the geometric discord(Bures distance),the other is the quantum correlation of non-freezing phenomenon.The results demonstrate that the machine learning method has reasonable performance in quantum correlation research.展开更多
In recent years,as the popularity of anonymous currencies such as Bitcoin has made the tracking of ransomware attackers more difficult,the amount of ransomware attacks against personal computers and enterprise product...In recent years,as the popularity of anonymous currencies such as Bitcoin has made the tracking of ransomware attackers more difficult,the amount of ransomware attacks against personal computers and enterprise production servers is increasing rapidly.The ransomware has a wide range of influence and spreads all over the world.It is affecting many industries including internet,education,medical care,traditional industry,etc.This paper uses the idea of virus immunity to design an immunization solution for ransomware viruses to solve the problems of traditional ransomware defense methods(such as anti-virus software,firewalls,etc.),which cannot meet the requirements of rapid detection and immediate prevention of new outbreaks attacks.Our scheme includes two parts:server and client.The server provides an immune configuration file and configuration file management functions,including a configuration file module,a cryptography algorithm module,and a display module.The client obtains the immunization configuration file from server in real time,and performs the corresponding operations according to the configuration file to make the computer have an immune function for a specific ransomware,including an update module,a configuration file module,a cryptography algorithm module,a control module,and a log module.This scheme controls mutexes,services,files and registries respectively,to destroy the triggering conditions of the virus and finally achieve the purpose of immunizing a computer from a specific ransomware.展开更多
We synthesized NaY(MoO4)2:Eu3+phosphors of different doping concentrations by a molten salt method.This facile way possesses advantages such as simple process,lower calcination temperature(350℃)and small particle siz...We synthesized NaY(MoO4)2:Eu3+phosphors of different doping concentrations by a molten salt method.This facile way possesses advantages such as simple process,lower calcination temperature(350℃)and small particle size(70 nm).The crystal system is tetragonal phase and crystal lattice is body centered.The photo luminescence measurements including emission spectra,excitation spectra and fluorescence decay curves were carried out,elucidating that NaY(MoO4)2:Eu3+can be effectively excited by near UV and blue light.Moreover,it can be concluded that Eu3+energy transfer type is exchange interaction.Huang-Rhys factor and the critical energy transfer distance(Rc)were calculated to be 0.043 and 0.995 nm,respectively.Auzel’s model was used to obtain the intrinsic radiative transition lifetime of5 D0 level(τ0=0.923 ms).Furthermore,a calculation method was used to calculate refractive index n of nontransparent NaY(MoO4)2:1 mol%Eu3+phosphor,and n was obtained to be 1.86.展开更多
Grinding is one of the most widely used material removal methods at the end of many process chains.Grinding force is related to almost all grinding parameters,which has a great influence on material removal rate,dimen...Grinding is one of the most widely used material removal methods at the end of many process chains.Grinding force is related to almost all grinding parameters,which has a great influence on material removal rate,dimensional and shape accuracy,surface and subsurface integrity,thermodynamics,dynamics,wheel durability,and machining system deformation.Considering that grinding force is related to almost all grinding parameters,grinding force can be used to detect grinding wheel wear,energy calculation,chatter suppression,force control and grinding process simulation.Accurate prediction of grinding forces is important for optimizing grinding parameters and the structure of grinding machines and fixtures.Although there are substantial research papers on grinding mechanics,a comprehensive review on the modeling of grinding mechanics is still absent from the literature.To fill this gap,this work reviews and introduces theoretical methods and applications of mechanics in grinding from the aspects of modeling principles,limitations and possible future trendencies.展开更多
Purpose:To investigate the role of N6-methyladenosine(m^(6)A)RNA modification in the pathogenesis of Graves'ophthalmopathy(GO).Methods:Surgically excised extraocular muscles from 7 patients with GO and 5 subjects ...Purpose:To investigate the role of N6-methyladenosine(m^(6)A)RNA modification in the pathogenesis of Graves'ophthalmopathy(GO).Methods:Surgically excised extraocular muscles from 7 patients with GO and 5 subjects without GO were used.The global m^(6)A levels in the specimens were determined using an m^(6)A RNA methylation quantification kit.RNA sequencing(RNA-seq)was used to analyze the molecules involved in the regulation of m^(6)A RNA methylation and the differential expression of mRNAs between the two groups(4 eyes,respectively).The expression of m^(6)A RNA modification genes was evaluated by real-time PCR.The functional implications of the gene alterations between the GO and control specimens were determined by Gene Ontology analysis.Results:The m^(6)A level was significantly increased in the specimens of GO patients compared to the control specimens(P<0.05).The expression of m^(6)A methylation regulators,such as WT1 associated protein(WTAP),alkylation repair homolog protein 5(ALKBH5),E74 like ETS transcription factor 3(ELF3),YTH N6-methyladenosine RNA binding protein 2(YTHDF2),YTHDF3 and YTH domain containing 2(YTHDC2),was significantly upregulated(P<0.05).Gene Ontology enrichment analysis showed that the most highly upregulated genes and biological pathways were related to the immune response and inflammatory processes such as lymphocyte activation,leukocyte differentiation,cytokine production and cytokine-mediated signaling pathways.Conclusions:Our results suggest that m^(6)A methylation may play a critical role in the pathogenesis of GO and that targeting genes that regulate m^(6)A methylation may provide a new therapeutic approach for GO.展开更多
The relationship between the properties of PCBs and the behavior of soil and sediment is reviewed. The sorp-tion phenomena of PCBs in the environment are described with different models. The research progress on the s...The relationship between the properties of PCBs and the behavior of soil and sediment is reviewed. The sorp-tion phenomena of PCBs in the environment are described with different models. The research progress on the sorption mechanisms is also discussed.展开更多
Introduction:Pneumoconiosis represents the most prevalent occupational disease in China,with coal workers’pneumoconiosis(CWP)showing the highest incidence.Analysis of volatile organic compounds(VOCs)in the exhaled br...Introduction:Pneumoconiosis represents the most prevalent occupational disease in China,with coal workers’pneumoconiosis(CWP)showing the highest incidence.Analysis of volatile organic compounds(VOCs)in the exhaled breath of CWP patients may provide novel insights into its pathogenesis.Methods:Study data were collected through questionnaires and medical examinations.Thermal desorption-gas chromatography-mass spectrometry was employed for targeted VOC analysis.Differential VOCs were identified using OPLS-DA,the Mann-Whitney U test,and fold change analysis.The discriminatory efficacy of differential VOCs was evaluated using receiver operating characteristic(ROC)curves.Spearman correlation analysis explored relationships between differential VOCs,lung function indices,and blood cell levels.Results:The pneumoconiosis group showed elevated concentrations of 10 compounds,including isopentane,n-pentane,and isoprene,while four compounds,including 2,4-dimethylpentane,methylcyclohexane,2,3,4-trimethylpentane,and 2-methylheptane showed decreased concentrations.Combined univariate and multivariate statistical analyses identified six significant VOCs,including isopentane and pentane.Notably,isopentane and npentane demonstrated negative correlations with forced vital capacity and levels,while 2-methylheptane showed positive correlations.Discussion:Clear metabolic differences in VOCs exist between CWP patients and non-dust-exposed healthy controls.Six compounds—isopentane,npentane,3-methylpentane,n-hexane,cyclohexane,and 2-methylheptane—in exhaled breath demonstrate potential as biomarkers for CWP.展开更多
Intermolecular charge transfer(inter-CT)is commonly considered to quench luminescence in molecular aggregates,especially for near-infrared(NIR)emission.Herein,by elaborate comparison ofπ-bridge effects in donor/accep...Intermolecular charge transfer(inter-CT)is commonly considered to quench luminescence in molecular aggregates,especially for near-infrared(NIR)emission.Herein,by elaborate comparison ofπ-bridge effects in donor/acceptor(D/A)molecules,it is disclosed that aπ-bridge is essential in D/A molecule to involve inter-CT in aggregates for inducing desired thermally activated delayed fluorescence(TADF)and largely suppressing non-radiative decays,and importantly,electrondonatingπ-bridge is critical to maximize radiative decay for inter-CT dominated emission by effective electronic coupling with bright intramolecular charge transfer(intra-CT)for high-efficiency NIR emission.As a proof-of-concept,TPATAP with thienyl asπ-bridge realized prominent photoluminescence quantum yields of 18.9%at 788 nm in solid films,and achieved record-high maximum external quantum efficiencies of 4.53%at 785 nm in devices.These findings provide fresh insight into interplay between inter-CT and intra-CT in molecular aggregates and open a new avenue to attenuate the limitation of energy gap law for developing highly efficient NIR emitters and improving the luminescent efficiency of various inter-CT systems,such as organic photovoltaic,organic long persistent luminescence,etc.展开更多
基金supported by the National Natural Science Foundation of China(61502082)National Key R&D Program of China,Grant No.(2018YFA0306703).
文摘Quantum correlation shows a fascinating nature of quantum mechanics and plays an important role in some physics topics,especially in the field of quantum information.Quantum correlations of the composite system can be quantified by resorting to geometric or entropy methods,and all these quantification methods exhibit the peculiar freezing phenomenon.The challenge is to find the characteristics of the quantum states that generate the freezing phenomenon,rather than only study the conditions which generate this phenomenon under a certain quantum system.In essence,this is a classification problem.Machine learning has become an effective method for researchers to study classification and feature generation.In this work,we prove that the machine learning can solve the problem of X form quantum states,which is a problem of physical significance.Subsequently,we apply the density-based spatial clustering of applications with noise(DBSCAN)algorithm and the decision tree to divide quantum states into two different groups.Our goal is to classify the quantum correlations of quantum states into two classes:one is the quantum correlation with freezing phenomenon for both Rènyi discord(α=2)and the geometric discord(Bures distance),the other is the quantum correlation of non-freezing phenomenon.The results demonstrate that the machine learning method has reasonable performance in quantum correlation research.
基金This work is supported in part by the National Natural Science Foundation of China under grant No.61872069in part by the Fundamental Research Funds for the Central Universities(N2017012)。
文摘In recent years,as the popularity of anonymous currencies such as Bitcoin has made the tracking of ransomware attackers more difficult,the amount of ransomware attacks against personal computers and enterprise production servers is increasing rapidly.The ransomware has a wide range of influence and spreads all over the world.It is affecting many industries including internet,education,medical care,traditional industry,etc.This paper uses the idea of virus immunity to design an immunization solution for ransomware viruses to solve the problems of traditional ransomware defense methods(such as anti-virus software,firewalls,etc.),which cannot meet the requirements of rapid detection and immediate prevention of new outbreaks attacks.Our scheme includes two parts:server and client.The server provides an immune configuration file and configuration file management functions,including a configuration file module,a cryptography algorithm module,and a display module.The client obtains the immunization configuration file from server in real time,and performs the corresponding operations according to the configuration file to make the computer have an immune function for a specific ransomware,including an update module,a configuration file module,a cryptography algorithm module,a control module,and a log module.This scheme controls mutexes,services,files and registries respectively,to destroy the triggering conditions of the virus and finally achieve the purpose of immunizing a computer from a specific ransomware.
基金Project supported by the National Natural Science Foundation of China(51002041)
文摘We synthesized NaY(MoO4)2:Eu3+phosphors of different doping concentrations by a molten salt method.This facile way possesses advantages such as simple process,lower calcination temperature(350℃)and small particle size(70 nm).The crystal system is tetragonal phase and crystal lattice is body centered.The photo luminescence measurements including emission spectra,excitation spectra and fluorescence decay curves were carried out,elucidating that NaY(MoO4)2:Eu3+can be effectively excited by near UV and blue light.Moreover,it can be concluded that Eu3+energy transfer type is exchange interaction.Huang-Rhys factor and the critical energy transfer distance(Rc)were calculated to be 0.043 and 0.995 nm,respectively.Auzel’s model was used to obtain the intrinsic radiative transition lifetime of5 D0 level(τ0=0.923 ms).Furthermore,a calculation method was used to calculate refractive index n of nontransparent NaY(MoO4)2:1 mol%Eu3+phosphor,and n was obtained to be 1.86.
基金co-supported by the Enterprise Innovation and Development Joint Program of the National Natural Science Foundation of China (No. U20B2032)National Natural Science Foundation of China (No. 51875135)
文摘Grinding is one of the most widely used material removal methods at the end of many process chains.Grinding force is related to almost all grinding parameters,which has a great influence on material removal rate,dimensional and shape accuracy,surface and subsurface integrity,thermodynamics,dynamics,wheel durability,and machining system deformation.Considering that grinding force is related to almost all grinding parameters,grinding force can be used to detect grinding wheel wear,energy calculation,chatter suppression,force control and grinding process simulation.Accurate prediction of grinding forces is important for optimizing grinding parameters and the structure of grinding machines and fixtures.Although there are substantial research papers on grinding mechanics,a comprehensive review on the modeling of grinding mechanics is still absent from the literature.To fill this gap,this work reviews and introduces theoretical methods and applications of mechanics in grinding from the aspects of modeling principles,limitations and possible future trendencies.
基金This work was supported by grants from the National Natural Science Foundation of China(grant nos.81770943 and 81873681)the Beijing Municipal Science and Technology Commission(Capital Char-acteristic Clinic Applied Research Project,Z161100000516037).
文摘Purpose:To investigate the role of N6-methyladenosine(m^(6)A)RNA modification in the pathogenesis of Graves'ophthalmopathy(GO).Methods:Surgically excised extraocular muscles from 7 patients with GO and 5 subjects without GO were used.The global m^(6)A levels in the specimens were determined using an m^(6)A RNA methylation quantification kit.RNA sequencing(RNA-seq)was used to analyze the molecules involved in the regulation of m^(6)A RNA methylation and the differential expression of mRNAs between the two groups(4 eyes,respectively).The expression of m^(6)A RNA modification genes was evaluated by real-time PCR.The functional implications of the gene alterations between the GO and control specimens were determined by Gene Ontology analysis.Results:The m^(6)A level was significantly increased in the specimens of GO patients compared to the control specimens(P<0.05).The expression of m^(6)A methylation regulators,such as WT1 associated protein(WTAP),alkylation repair homolog protein 5(ALKBH5),E74 like ETS transcription factor 3(ELF3),YTH N6-methyladenosine RNA binding protein 2(YTHDF2),YTHDF3 and YTH domain containing 2(YTHDC2),was significantly upregulated(P<0.05).Gene Ontology enrichment analysis showed that the most highly upregulated genes and biological pathways were related to the immune response and inflammatory processes such as lymphocyte activation,leukocyte differentiation,cytokine production and cytokine-mediated signaling pathways.Conclusions:Our results suggest that m^(6)A methylation may play a critical role in the pathogenesis of GO and that targeting genes that regulate m^(6)A methylation may provide a new therapeutic approach for GO.
基金the Knowledge Innovation Program of the Chinese Academy of Sciences (Grant No. RCEES9906) the Bureau of Resource and Environment of the CAS (Grant No. KZ951-B-1-209-02) the National Natural Science Foundation of China (Grant No. 29837180).
文摘The relationship between the properties of PCBs and the behavior of soil and sediment is reviewed. The sorp-tion phenomena of PCBs in the environment are described with different models. The research progress on the sorption mechanisms is also discussed.
基金Supported by the National Center for Occupational Safety and Health Self-management Project of China(2019009)and the Central Public-Interest Scientific Institution Basal Research Project of China(2020-PT320-005).
文摘Introduction:Pneumoconiosis represents the most prevalent occupational disease in China,with coal workers’pneumoconiosis(CWP)showing the highest incidence.Analysis of volatile organic compounds(VOCs)in the exhaled breath of CWP patients may provide novel insights into its pathogenesis.Methods:Study data were collected through questionnaires and medical examinations.Thermal desorption-gas chromatography-mass spectrometry was employed for targeted VOC analysis.Differential VOCs were identified using OPLS-DA,the Mann-Whitney U test,and fold change analysis.The discriminatory efficacy of differential VOCs was evaluated using receiver operating characteristic(ROC)curves.Spearman correlation analysis explored relationships between differential VOCs,lung function indices,and blood cell levels.Results:The pneumoconiosis group showed elevated concentrations of 10 compounds,including isopentane,n-pentane,and isoprene,while four compounds,including 2,4-dimethylpentane,methylcyclohexane,2,3,4-trimethylpentane,and 2-methylheptane showed decreased concentrations.Combined univariate and multivariate statistical analyses identified six significant VOCs,including isopentane and pentane.Notably,isopentane and npentane demonstrated negative correlations with forced vital capacity and levels,while 2-methylheptane showed positive correlations.Discussion:Clear metabolic differences in VOCs exist between CWP patients and non-dust-exposed healthy controls.Six compounds—isopentane,npentane,3-methylpentane,n-hexane,cyclohexane,and 2-methylheptane—in exhaled breath demonstrate potential as biomarkers for CWP.
基金National Key R&D Program of China,Grant/Award Number:2020YFA0715000National Natural Science Foundation of China,Grant/Award Number:51773109。
文摘Intermolecular charge transfer(inter-CT)is commonly considered to quench luminescence in molecular aggregates,especially for near-infrared(NIR)emission.Herein,by elaborate comparison ofπ-bridge effects in donor/acceptor(D/A)molecules,it is disclosed that aπ-bridge is essential in D/A molecule to involve inter-CT in aggregates for inducing desired thermally activated delayed fluorescence(TADF)and largely suppressing non-radiative decays,and importantly,electrondonatingπ-bridge is critical to maximize radiative decay for inter-CT dominated emission by effective electronic coupling with bright intramolecular charge transfer(intra-CT)for high-efficiency NIR emission.As a proof-of-concept,TPATAP with thienyl asπ-bridge realized prominent photoluminescence quantum yields of 18.9%at 788 nm in solid films,and achieved record-high maximum external quantum efficiencies of 4.53%at 785 nm in devices.These findings provide fresh insight into interplay between inter-CT and intra-CT in molecular aggregates and open a new avenue to attenuate the limitation of energy gap law for developing highly efficient NIR emitters and improving the luminescent efficiency of various inter-CT systems,such as organic photovoltaic,organic long persistent luminescence,etc.
