The electrical coupling of myocytes and fibroblasts can play a role in inhibiting electrical impluse propagation in cardiac muscle. To understand the function of fibroblast–myocyte coupling in the aging heart, the sp...The electrical coupling of myocytes and fibroblasts can play a role in inhibiting electrical impluse propagation in cardiac muscle. To understand the function of fibroblast–myocyte coupling in the aging heart, the spiral-wave dynamics in the duplex networks with inhibitory coupling is numerically investigated by the Br–Eiswirth model. The numerical results show that the inhibitory coupling can change the wave amplitude, excited phase duration and excitability of the system. When the related parameters are properly chosen, the inhibitory coupling can induce local abnormal oscillation in the system and the Eckhaus instability of the spiral wave. For the dense inhibitory network, the maximal decrement（maximal increment） in the excited phase duration can reach 24.3%（13.4%）, whereas the maximal decrement in wave amplitude approaches 28.1%. Upon increasing the inhibitory coupling strength, the system excitability is reduced and even completely suppressed when the interval between grid points in the inhibitory network is small enough. Moreover, the inhibitory coupling can lead to richer phase transition scenarios of the system, such as the transition from a stable spiral wave to turbulence and the transition from a meandering spiral wave to a planar wave. In addition, the self-sustaining planar wave, the unique meandering of spiral wave and inward spiral wave are observed. The physical mechanisms behind the phenomena are analyzed.展开更多
This paper discusses Hawking radiation from the charged and magnetized Bafiados-Teitelboim-Zanelli （BTZ） black hole from the viewpoint of anomaly, initiated by Robinson and Wilczek recently. It reconstructs the elec...This paper discusses Hawking radiation from the charged and magnetized Bafiados-Teitelboim-Zanelli （BTZ） black hole from the viewpoint of anomaly, initiated by Robinson and Wilczek recently. It reconstructs the electromagnetic field tensor and the Lagrangian of the field corresponding to the source with electric and magnetic charges to redefine an equivalent charge and gauge potential. It employs the covariant anomaly cancellation method to determine the compensating fluxes of charge flow and energy-momentum tensor, which are shown to match with those of the 2- dimensional blackbody radiation at the Hawking temperature exactly.展开更多
This paper discusses tunneling of scalar particles and Dirac particles from the Taub-NUT-AdS black hole by the Hamilto-Jacobi equation, initially used by Angheben et al, and the Dirac equation, recently proposed by Ke...This paper discusses tunneling of scalar particles and Dirac particles from the Taub-NUT-AdS black hole by the Hamilto-Jacobi equation, initially used by Angheben et al, and the Dirac equation, recently proposed by Kerner and Mann. This is performed in the dragging coordinate frame so as to avoid the ergosphere dragging effect. A general form is obtained for the temperature of scalar and Dirac particles tunneling from the Taub-NUT-Ads black hole, which is commensurate with other methods as expected.展开更多
According to Bohr-Sommerfeld quantization rule,an equally spaced horizon area spectrum of a static,spherically symmetric black hole was obtained under an adiabatic invariant action.This method can be extended to the r...According to Bohr-Sommerfeld quantization rule,an equally spaced horizon area spectrum of a static,spherically symmetric black hole was obtained under an adiabatic invariant action.This method can be extended to the rotating black holes.As an example,this method is applied to the rotating BTZ black hole and the quantized spectrum of the horizon area is obtained.It is shown that the area spectrum of the rotating BTZ black hole is also equally spaced and irrelevant to the rotating parameter,which is consistent with the Bekenstein conjecture.Specifically,the derivation does not need the quasinormal frequencies and the small angular momentum limit.展开更多
As an alternative energy,hydrogen can be converted into electrical energy via direct electrochemical conversion in fuel cells.One important drawback of full cells is the sluggish oxygen reduction reaction(ORR)promoted...As an alternative energy,hydrogen can be converted into electrical energy via direct electrochemical conversion in fuel cells.One important drawback of full cells is the sluggish oxygen reduction reaction(ORR)promoted by the high-loading of platinum-group-metal(PGM)electrocatalysts.Fe-N-C family has been received extensive attention because of its low cost,long service life and high oxygen reduction reaction activity in recent years.In order to further enhance the ORR activity,the synthesis method,morphology regulation and catalytic mechanism of the active sites in Fe-N-C catalysts are investigated.This paper reviews the research progress of Fe-N-C from nanoparticles to single atoms.The structure-activity relationship and catalytic mechanism of the catalyst are studied and discussed,which provide a guidance for rational design of the catalyst,so as to promote the more reasonable design of Fe-N-C materials.展开更多
Based on the work of Kerner and Mann, fermions tunneling from the Horowitz-Strominger Dilaton black hole on the membrane is studied. Owing to the coupling among electromagnetic field, matter field and gravity field, t...Based on the work of Kerner and Mann, fermions tunneling from the Horowitz-Strominger Dilaton black hole on the membrane is studied. Owing to the coupling among electromagnetic field, matter field and gravity field, the Dirac equation of charged particles is introduced, and according to that, the expected emission temperature is obtained. After the self-gravitational interaction is considered, it is found that the tunneling rate of fermions also satisfies the underlying Unitary theory as the case of scalar particles.展开更多
We present a short and direct derivation of Hawking radiation by using the Damour-Ruffini method, as taking into account the self-gravitational interaction from the Kerr black hole. It is found that the radiation is n...We present a short and direct derivation of Hawking radiation by using the Damour-Ruffini method, as taking into account the self-gravitational interaction from the Kerr black hole. It is found that the radiation is not exactly thermal, and because the derivation obeys conservation laws, the non-thermal Hawking radiation can carry information from the black hole. So it can be used to explain the black hole information paradox, and the process satisfies unitary.展开更多
基金Supported by the National Basic Research Program of China under Grant No 2006CB705500, the National Natural Science Foundation of China under Grant Nos 10975126 and 10635040, the Specialized Research Fund for the Doctoral Program of Higher Education of China under Grant No 20093402110032, and the Scientific Research Fund of Sichuan Provincial Education Department （08ZA037, 09ZA103）.
基金supported by the National Natural Science Foundation of China(Grant Nos.11565005 and 11365003)
文摘The electrical coupling of myocytes and fibroblasts can play a role in inhibiting electrical impluse propagation in cardiac muscle. To understand the function of fibroblast–myocyte coupling in the aging heart, the spiral-wave dynamics in the duplex networks with inhibitory coupling is numerically investigated by the Br–Eiswirth model. The numerical results show that the inhibitory coupling can change the wave amplitude, excited phase duration and excitability of the system. When the related parameters are properly chosen, the inhibitory coupling can induce local abnormal oscillation in the system and the Eckhaus instability of the spiral wave. For the dense inhibitory network, the maximal decrement（maximal increment） in the excited phase duration can reach 24.3%（13.4%）, whereas the maximal decrement in wave amplitude approaches 28.1%. Upon increasing the inhibitory coupling strength, the system excitability is reduced and even completely suppressed when the interval between grid points in the inhibitory network is small enough. Moreover, the inhibitory coupling can lead to richer phase transition scenarios of the system, such as the transition from a stable spiral wave to turbulence and the transition from a meandering spiral wave to a planar wave. In addition, the self-sustaining planar wave, the unique meandering of spiral wave and inward spiral wave are observed. The physical mechanisms behind the phenomena are analyzed.
基金supported by the National Natural Science Foundation of China (Grant No 10773008)
文摘This paper discusses Hawking radiation from the charged and magnetized Bafiados-Teitelboim-Zanelli （BTZ） black hole from the viewpoint of anomaly, initiated by Robinson and Wilczek recently. It reconstructs the electromagnetic field tensor and the Lagrangian of the field corresponding to the source with electric and magnetic charges to redefine an equivalent charge and gauge potential. It employs the covariant anomaly cancellation method to determine the compensating fluxes of charge flow and energy-momentum tensor, which are shown to match with those of the 2- dimensional blackbody radiation at the Hawking temperature exactly.
基金Project supported by the Natural Science Foundation of Sichuan Education Office of China (Grant Nos 08ZA137 and 07ZC039)
文摘This paper discusses tunneling of scalar particles and Dirac particles from the Taub-NUT-AdS black hole by the Hamilto-Jacobi equation, initially used by Angheben et al, and the Dirac equation, recently proposed by Kerner and Mann. This is performed in the dragging coordinate frame so as to avoid the ergosphere dragging effect. A general form is obtained for the temperature of scalar and Dirac particles tunneling from the Taub-NUT-Ads black hole, which is commensurate with other methods as expected.
基金supported by the National Natural Science Foundation of China(Grant Nos.10773002,10875012 and 11175019)the Fundamental Research Funds for the Central Universities(Grant No.105116)the Team Research Program of Hubei University for Nationalities(Grant No. MY2011T006)
文摘According to Bohr-Sommerfeld quantization rule,an equally spaced horizon area spectrum of a static,spherically symmetric black hole was obtained under an adiabatic invariant action.This method can be extended to the rotating black holes.As an example,this method is applied to the rotating BTZ black hole and the quantized spectrum of the horizon area is obtained.It is shown that the area spectrum of the rotating BTZ black hole is also equally spaced and irrelevant to the rotating parameter,which is consistent with the Bekenstein conjecture.Specifically,the derivation does not need the quasinormal frequencies and the small angular momentum limit.
基金W.X.C.acknowledges the National Natural Science Foundation of China(No.21801015)W.X.C.acknowledges the Beijing Institute of Technology Research Fund Program for Young Scholars(No.3090012221909).
文摘As an alternative energy,hydrogen can be converted into electrical energy via direct electrochemical conversion in fuel cells.One important drawback of full cells is the sluggish oxygen reduction reaction(ORR)promoted by the high-loading of platinum-group-metal(PGM)electrocatalysts.Fe-N-C family has been received extensive attention because of its low cost,long service life and high oxygen reduction reaction activity in recent years.In order to further enhance the ORR activity,the synthesis method,morphology regulation and catalytic mechanism of the active sites in Fe-N-C catalysts are investigated.This paper reviews the research progress of Fe-N-C from nanoparticles to single atoms.The structure-activity relationship and catalytic mechanism of the catalyst are studied and discussed,which provide a guidance for rational design of the catalyst,so as to promote the more reasonable design of Fe-N-C materials.
基金Supported by the Natural Science Foundation of Sichuan Education Office (Grant No.07ZC039)
文摘Based on the work of Kerner and Mann, fermions tunneling from the Horowitz-Strominger Dilaton black hole on the membrane is studied. Owing to the coupling among electromagnetic field, matter field and gravity field, the Dirac equation of charged particles is introduced, and according to that, the expected emission temperature is obtained. After the self-gravitational interaction is considered, it is found that the tunneling rate of fermions also satisfies the underlying Unitary theory as the case of scalar particles.
基金Supported by Scientific and Technological Foundation of Chongqing Municipal Education Commission (KJ0707011)
文摘We present a short and direct derivation of Hawking radiation by using the Damour-Ruffini method, as taking into account the self-gravitational interaction from the Kerr black hole. It is found that the radiation is not exactly thermal, and because the derivation obeys conservation laws, the non-thermal Hawking radiation can carry information from the black hole. So it can be used to explain the black hole information paradox, and the process satisfies unitary.
