This paper brings attention on the hybrid synchronization of the Chen hyper-chaotic system by using some simple controllers. We give the sufficient conditions for achieving the goal by using the Lyapunov stability the...This paper brings attention on the hybrid synchronization of the Chen hyper-chaotic system by using some simple controllers. We give the sufficient conditions for achieving the goal by using the Lyapunov stability theory, and we verify our conclusion by numerical simulations.展开更多
Background:The aim of this study is to investigate the effect of the oil price and its volatility on the stock market of Pakistan before and after the 2007 financial crisis period.Methods:The analyses are carried out ...Background:The aim of this study is to investigate the effect of the oil price and its volatility on the stock market of Pakistan before and after the 2007 financial crisis period.Methods:The analyses are carried out on daily data for the period from July 31,2000 to July 31,2014.This study uses several econometric techniques for the analyses,namely,the Johansen-Juselius cointegration test,generalized autoregressive conditional heteroskedasticity(GARCH)model,exponential generalized autoregressive conditional heteroskedasticity(EGARCH)model,variance decomposition method,and impulse response function.Results:The results of the cointegration method indicate a significant long-run association between stock market and oil prices in the pre-crisis period.The EGARCH model shows that oil price returns have a significant effect on stock market returns in both sub-periods,while the result for the GARCH model is significant only in the postcrisis period.We find a significant effect of oil price volatility on the stock market in both sub-periods from the GARCH model.Furthermore,the EGARCH model shows an asymmetric effect of oil price volatility on the stock market in the pre-crisis period.Variance decomposition shows that stock market variations are mostly explained by selfinnovation.Moreover,the impulse response function results show that oil price shocks affected the stock market adversely in the pre-crisis period but positively in the postcrisis period.Conclusions:This study suggests that economic policymakers and investors should consider the oil price as an important factor affecting stock market returns.展开更多
The cooperative behaviors resulted from the interaction of coupled identical oscillators have been investigated intensively.However,the coupled oscillators in practice are nonidentical,and there exist mismatched param...The cooperative behaviors resulted from the interaction of coupled identical oscillators have been investigated intensively.However,the coupled oscillators in practice are nonidentical,and there exist mismatched parameters.It has been proved that under certain conditions,complete synchronization can take place in coupled nonidentical oscillators with the same equilibrium points,yet other cooperative behaviors are not addressed.In this paper,we further consider two coupled nonidentical oscillators with the same equilibrium points,where one oscillator is convergent while the other is chaotic,and explore their cooperative behaviors.We find that the coupling mode and the coupling strength can bring the coupled oscillators to different cooperation behaviors in unidirectional or undirected couplings.In the case of directed coupling,death islands appear in two-parameter spaces.The mechanism inducing these transitions is presented.展开更多
With the advancement of modern science and technology, large scientific facilities are increasingly oriented toward demand and application, and can be used for basic research as well as serving multiple disciplines. D...With the advancement of modern science and technology, large scientific facilities are increasingly oriented toward demand and application, and can be used for basic research as well as serving multiple disciplines. Developing large scientific facilities and related analytical technologies enhances understanding of large scientific facilities and popularizes their application in research across multiple disciplines. The combination of light or neutron sources from large scientific facilities and advanced analytical technologies can be achieved for materials structure information, dynamics study of chemical reactions, high dissociation of biomolecules, 3D visualization of energy materials or biological samples, etc. We first introduce the progress of domestic large scientific facilities of synchrotron radiation(SR) and free electron lasers(FELs) with different wavelengths and neutron sources.We further discuss the comparison between Chinese and typical foreign facilities in X-ray radiation from X-ray tubes, synchrotrons, X-ray FELs, and neutron sources based on physical parameters of light and neutron sources. In addition, we focus on the technological progress and perspectives combined with advanced X-ray radiation and neutron sources of large scientific facilities in China, especially in the nanoscience fields of energy catalysis and biological science. We hope that this roadmap will provide references on technology and methods to experimental users, as well as prospects for future development of technologies based on large research infrastructure facilities. Comprehensive studies and guidelines for basic research to practical application in various disciplines can be made with the assistance of large scientific facilities.展开更多
The outbreak of coronavirus disease 2019(COVID-19) caused by SARS-CoV-2 has created a global health crisis. SARS-CoV-2 infects varieties of tissues where the known receptor ACE2 is low or almost absent, suggesting the...The outbreak of coronavirus disease 2019(COVID-19) caused by SARS-CoV-2 has created a global health crisis. SARS-CoV-2 infects varieties of tissues where the known receptor ACE2 is low or almost absent, suggesting the existence of alternative viral entry pathways. Here, we performed a genome-wide barcoded-CRISPRa screen to identify novel host factors that enable SARS-CoV-2 infection. Beyond known host proteins, i.e., ACE2, TMPRSS2, and NRP1, we identified multiple host components,among which LDLRAD3, TMEM30A, and CLEC4G were confirmed as functional receptors for SARS-CoV-2. All these membrane proteins bind directly to spike’s N-terminal domain(NTD). Their essential and physiological roles have been confirmed in either neuron or liver cells. In particular, LDLRAD3 and CLEC4G mediate SARS-CoV-2 entry and infection in an ACE2-independent fashion. The identification of the novel receptors and entry mechanisms could advance our understanding of the multiorgan tropism of SARS-CoV-2, and may shed light on the development of COVID-19 countermeasures.展开更多
FAPKC4, a public key cryptosystem based on automata theory, is generalized so that component automata of compound automata in user’s public key would not be restricted to memory finite automata. The generalized FAPKC...FAPKC4, a public key cryptosystem based on automata theory, is generalized so that component automata of compound automata in user’s public key would not be restricted to memory finite automata. The generalized FAPKCA can be used in encryption and implementing digital signatures as well.展开更多
With the increasing number of sequenced species,phylogenetic profiling(PP)has become a powerful method to predict functional genes based on co-evolutionary information.However,its potential in plant genomics has not y...With the increasing number of sequenced species,phylogenetic profiling(PP)has become a powerful method to predict functional genes based on co-evolutionary information.However,its potential in plant genomics has not yet been fully explored.In this context,we combined the power of machine learning and PP to identify salt stress-related genes in a halophytic grass,Spartina alterniflora,using evolutionary information generated from 365 plant species.Our results showed that the genes highly co-evolved with known salt stress-related genes are enriched in biological processes of ion transport,detoxification and metabolic pathways.For ion transport,five identified genes coding two sodium and three potassium transporters were validated to be able to uptake Na?.In addition,we identified two orthologs of trichome-related AtR3-MYB genes,SaCPC1 and SaCPC2,which may be involved in salinity responses.Genes co-evolved with SaCPCs were enriched in functions related to the circadian rhythm and abiotic stress responses.Overall,this work demonstrates the feasibility of mining salt stress-related genes using evolutionary information,highlighting the potential of PP as a valuable tool for plant functional genomics.展开更多
文摘This paper brings attention on the hybrid synchronization of the Chen hyper-chaotic system by using some simple controllers. We give the sufficient conditions for achieving the goal by using the Lyapunov stability theory, and we verify our conclusion by numerical simulations.
基金This article was supported by Supported by National Natural Science Foundation of China.(Project Number:71472030).
文摘Background:The aim of this study is to investigate the effect of the oil price and its volatility on the stock market of Pakistan before and after the 2007 financial crisis period.Methods:The analyses are carried out on daily data for the period from July 31,2000 to July 31,2014.This study uses several econometric techniques for the analyses,namely,the Johansen-Juselius cointegration test,generalized autoregressive conditional heteroskedasticity(GARCH)model,exponential generalized autoregressive conditional heteroskedasticity(EGARCH)model,variance decomposition method,and impulse response function.Results:The results of the cointegration method indicate a significant long-run association between stock market and oil prices in the pre-crisis period.The EGARCH model shows that oil price returns have a significant effect on stock market returns in both sub-periods,while the result for the GARCH model is significant only in the postcrisis period.We find a significant effect of oil price volatility on the stock market in both sub-periods from the GARCH model.Furthermore,the EGARCH model shows an asymmetric effect of oil price volatility on the stock market in the pre-crisis period.Variance decomposition shows that stock market variations are mostly explained by selfinnovation.Moreover,the impulse response function results show that oil price shocks affected the stock market adversely in the pre-crisis period but positively in the postcrisis period.Conclusions:This study suggests that economic policymakers and investors should consider the oil price as an important factor affecting stock market returns.
基金supported by the National Natural Science Foundation of China(Grant No.11875135)Fundamental Research Funds for National University,China University of Geosciences(Wuhan)(Grant No.CUGGC05)。
文摘The cooperative behaviors resulted from the interaction of coupled identical oscillators have been investigated intensively.However,the coupled oscillators in practice are nonidentical,and there exist mismatched parameters.It has been proved that under certain conditions,complete synchronization can take place in coupled nonidentical oscillators with the same equilibrium points,yet other cooperative behaviors are not addressed.In this paper,we further consider two coupled nonidentical oscillators with the same equilibrium points,where one oscillator is convergent while the other is chaotic,and explore their cooperative behaviors.We find that the coupling mode and the coupling strength can bring the coupled oscillators to different cooperation behaviors in unidirectional or undirected couplings.In the case of directed coupling,death islands appear in two-parameter spaces.The mechanism inducing these transitions is presented.
基金supported by the National Basic Research Program of China (2022YFA1603701, 2021YFA1200900)the institutionalized scientific research platform relies on Beijing Synchrotron Radiation Facility of Chinese Academy of Sciences,the Strategic Priority Research Program of Chinese Academy of Sciences (XDB36000000)+2 种基金the National Natural Science Foundation of China (22027810, 82341044,22388101 and 22307028)the CAMS Innovation Fund for Medical Sciences(CIFMS 2019-I2M-5-018)the New Cornerstone Science Foundation。
文摘With the advancement of modern science and technology, large scientific facilities are increasingly oriented toward demand and application, and can be used for basic research as well as serving multiple disciplines. Developing large scientific facilities and related analytical technologies enhances understanding of large scientific facilities and popularizes their application in research across multiple disciplines. The combination of light or neutron sources from large scientific facilities and advanced analytical technologies can be achieved for materials structure information, dynamics study of chemical reactions, high dissociation of biomolecules, 3D visualization of energy materials or biological samples, etc. We first introduce the progress of domestic large scientific facilities of synchrotron radiation(SR) and free electron lasers(FELs) with different wavelengths and neutron sources.We further discuss the comparison between Chinese and typical foreign facilities in X-ray radiation from X-ray tubes, synchrotrons, X-ray FELs, and neutron sources based on physical parameters of light and neutron sources. In addition, we focus on the technological progress and perspectives combined with advanced X-ray radiation and neutron sources of large scientific facilities in China, especially in the nanoscience fields of energy catalysis and biological science. We hope that this roadmap will provide references on technology and methods to experimental users, as well as prospects for future development of technologies based on large research infrastructure facilities. Comprehensive studies and guidelines for basic research to practical application in various disciplines can be made with the assistance of large scientific facilities.
基金supported by funds from the National Key R&D Program of China (2020YFA0707800 to W.W., 2020YFA0707600 to Z.Z.)Beijing Municipal Science & Technology Commission (Z181100001318009)+4 种基金the National Natural Science Foundation of China (31930016)Beijing Advanced Innovation Center for Genomics at Peking University and the Peking-Tsinghua Center for Life Sciences (to W.W.)the National Natural Science Foundation of China (31870893)the National Major Science & Technology Project for Control and Prevention of Major Infectious Diseases in China (2018ZX10301401 to Z.Z.)China Postdoctoral Science Foundation (2020M670031 to Y.L.)
文摘The outbreak of coronavirus disease 2019(COVID-19) caused by SARS-CoV-2 has created a global health crisis. SARS-CoV-2 infects varieties of tissues where the known receptor ACE2 is low or almost absent, suggesting the existence of alternative viral entry pathways. Here, we performed a genome-wide barcoded-CRISPRa screen to identify novel host factors that enable SARS-CoV-2 infection. Beyond known host proteins, i.e., ACE2, TMPRSS2, and NRP1, we identified multiple host components,among which LDLRAD3, TMEM30A, and CLEC4G were confirmed as functional receptors for SARS-CoV-2. All these membrane proteins bind directly to spike’s N-terminal domain(NTD). Their essential and physiological roles have been confirmed in either neuron or liver cells. In particular, LDLRAD3 and CLEC4G mediate SARS-CoV-2 entry and infection in an ACE2-independent fashion. The identification of the novel receptors and entry mechanisms could advance our understanding of the multiorgan tropism of SARS-CoV-2, and may shed light on the development of COVID-19 countermeasures.
文摘FAPKC4, a public key cryptosystem based on automata theory, is generalized so that component automata of compound automata in user’s public key would not be restricted to memory finite automata. The generalized FAPKCA can be used in encryption and implementing digital signatures as well.
基金supported by the National Key R&D Program of China(2022YFF0711802)the Nanfan special project of the Chinese Academy of Agricultural Sciences(ZDXM2309)+1 种基金the National Natural Science Foundation of China(32022064)the Innovation Program of the Chinese Academy of Agricultural Sciences,the Alibaba Foundation,and the High-performance Computing Platform of YZBSTCACC.
文摘With the increasing number of sequenced species,phylogenetic profiling(PP)has become a powerful method to predict functional genes based on co-evolutionary information.However,its potential in plant genomics has not yet been fully explored.In this context,we combined the power of machine learning and PP to identify salt stress-related genes in a halophytic grass,Spartina alterniflora,using evolutionary information generated from 365 plant species.Our results showed that the genes highly co-evolved with known salt stress-related genes are enriched in biological processes of ion transport,detoxification and metabolic pathways.For ion transport,five identified genes coding two sodium and three potassium transporters were validated to be able to uptake Na?.In addition,we identified two orthologs of trichome-related AtR3-MYB genes,SaCPC1 and SaCPC2,which may be involved in salinity responses.Genes co-evolved with SaCPCs were enriched in functions related to the circadian rhythm and abiotic stress responses.Overall,this work demonstrates the feasibility of mining salt stress-related genes using evolutionary information,highlighting the potential of PP as a valuable tool for plant functional genomics.
