Classical Philadelphia-negative myeloproliferative neoplasms(MPNs),i.e.,polycythemia vera,essential thrombocythemia,and primary/secondary myelofibrosis,are clonal disorders of the hematopoietic stem cell in which an u...Classical Philadelphia-negative myeloproliferative neoplasms(MPNs),i.e.,polycythemia vera,essential thrombocythemia,and primary/secondary myelofibrosis,are clonal disorders of the hematopoietic stem cell in which an uncontrolled proliferation of terminally differentiated myeloid cells occurs.MPNs are characterized by mutations in driver genes,the JAK2V617F point mutation being the most commonly detected genetic alteration in these hematological malignancies.Thus,JAK inhibition has emerged as a potential therapeutic strategy in MPNs,with ruxolitinib being the first JAK inhibitor developed,approved,and prescribed in the management of these blood cancers.However,the use of ruxolitinib has been associated with a potential risk of infection,including opportunistic infections and reactivation of hepatitis B.Here,we briefly describe the association between ruxolitinib treatment in MPNs and hepatitis B reactivation.展开更多
Suppose that G is a planar cubic graph withχi(G)>5.We show that ifχi(H)<χi(G)for each planar cubic graph H of order less thanG,thenG is either a 3-connected simple planar cubic graph,or a planar graph obtaine...Suppose that G is a planar cubic graph withχi(G)>5.We show that ifχi(H)<χi(G)for each planar cubic graph H of order less thanG,thenG is either a 3-connected simple planar cubic graph,or a planar graph obtained from a simple cubic 3-connected planar graph by adding some earrings.This shows that a minimum non-5-injectively colorable simple planar cubic graph must be 3-connected.展开更多
This paper gives several structure-preserving schemes for the Degasperis-Procesi equation which has bi-Hamiltonian structures consisted of both complex and non-local Hamiltonian differential operators. For this sake, ...This paper gives several structure-preserving schemes for the Degasperis-Procesi equation which has bi-Hamiltonian structures consisted of both complex and non-local Hamiltonian differential operators. For this sake, few structure-preserving schemes have been proposed so far. In our work, based on one of the bi-Hamiltonian structures, a symplectic scheme and two new energy-preserving schemes are constructed. The symplecticity comes straightly from the application of the implicit midpoint method on the semi-discrete system which is proved to remain Hamiltonian, while the energy conservation is derived by the combination of the averaged vector field method of second and fourth order, respectively. Some numerical results are presented to show that the three schemes do have the advantages in numerical stability, accuracy in long time computing and ability to preserve the invariants of the DP equation.展开更多
In this paper,we propose an explicit symplectic Fourier pseudospectral method for solving the Klein-Gordon-Schr odinger equation.The key idea is to rewrite the equation as an infinite-dimensional Hamiltonian system an...In this paper,we propose an explicit symplectic Fourier pseudospectral method for solving the Klein-Gordon-Schr odinger equation.The key idea is to rewrite the equation as an infinite-dimensional Hamiltonian system and discrete the system by using Fourier pseudospectral method in space and symplectic Euler method in time.After composing two different symplectic Euler methods for the ODEs resulted from semi-discretization in space,we get a new explicit scheme for the target equation which is of second order in space and spectral accuracy in time.The canonical Hamiltonian form of the resulted ODEs is presented and the new derived scheme is proved strictly to be symplectic.The new scheme is totally explicitwhereas symplectic scheme are generally implicit or semi-implicit.Linear stability analysis is carried and a necessary Courant-Friedrichs-Lewy condition is given.The numerical results are reported to test the accuracy and efficiency of the proposed method in long-term computing.展开更多
文摘Classical Philadelphia-negative myeloproliferative neoplasms(MPNs),i.e.,polycythemia vera,essential thrombocythemia,and primary/secondary myelofibrosis,are clonal disorders of the hematopoietic stem cell in which an uncontrolled proliferation of terminally differentiated myeloid cells occurs.MPNs are characterized by mutations in driver genes,the JAK2V617F point mutation being the most commonly detected genetic alteration in these hematological malignancies.Thus,JAK inhibition has emerged as a potential therapeutic strategy in MPNs,with ruxolitinib being the first JAK inhibitor developed,approved,and prescribed in the management of these blood cancers.However,the use of ruxolitinib has been associated with a potential risk of infection,including opportunistic infections and reactivation of hepatitis B.Here,we briefly describe the association between ruxolitinib treatment in MPNs and hepatitis B reactivation.
基金This research was supported by the National Natural Science Foundation of China(Nos.11571180 and 11331003)the Natural Science Foundation of Jiangsu Higher Education Institutions of China(No.17KJB110010).
文摘Suppose that G is a planar cubic graph withχi(G)>5.We show that ifχi(H)<χi(G)for each planar cubic graph H of order less thanG,thenG is either a 3-connected simple planar cubic graph,or a planar graph obtained from a simple cubic 3-connected planar graph by adding some earrings.This shows that a minimum non-5-injectively colorable simple planar cubic graph must be 3-connected.
基金the National Natural Science Foundation of China (Grant No. 11771213)the National Key Research and Development Project of China (Grant No. 2016YFC0600310)the Major Projects of Natural Sciences of University in Jiangsu Province of China (Grant No. 15KJA110002).
文摘This paper gives several structure-preserving schemes for the Degasperis-Procesi equation which has bi-Hamiltonian structures consisted of both complex and non-local Hamiltonian differential operators. For this sake, few structure-preserving schemes have been proposed so far. In our work, based on one of the bi-Hamiltonian structures, a symplectic scheme and two new energy-preserving schemes are constructed. The symplecticity comes straightly from the application of the implicit midpoint method on the semi-discrete system which is proved to remain Hamiltonian, while the energy conservation is derived by the combination of the averaged vector field method of second and fourth order, respectively. Some numerical results are presented to show that the three schemes do have the advantages in numerical stability, accuracy in long time computing and ability to preserve the invariants of the DP equation.
基金This work is supported by the Jiangsu Collaborative Innovation Center for Climate Change,the National Natural Science Foundation of China(Grant Nos.11271195 and 11271196)and the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘In this paper,we propose an explicit symplectic Fourier pseudospectral method for solving the Klein-Gordon-Schr odinger equation.The key idea is to rewrite the equation as an infinite-dimensional Hamiltonian system and discrete the system by using Fourier pseudospectral method in space and symplectic Euler method in time.After composing two different symplectic Euler methods for the ODEs resulted from semi-discretization in space,we get a new explicit scheme for the target equation which is of second order in space and spectral accuracy in time.The canonical Hamiltonian form of the resulted ODEs is presented and the new derived scheme is proved strictly to be symplectic.The new scheme is totally explicitwhereas symplectic scheme are generally implicit or semi-implicit.Linear stability analysis is carried and a necessary Courant-Friedrichs-Lewy condition is given.The numerical results are reported to test the accuracy and efficiency of the proposed method in long-term computing.