The performance of adaptive beamforming degrades severely when the strong desired signal is present in training snapshots with model mismatch. A robust adaptive beamforming is proposed using interference covariance matrix reconstruction in this paper. In the proposed method, the eigenvalue and eigenvector of desired signal is determined by calculating the correlation coefficients between eigenvectors of sample covariance matrix and the presumed array steering vector. Subsequently, the covariance matrix is reconstructed after removing the desired signal component from signal subspace. Finally, the average noise power is computed by estimating the noise subspace dimensions indirectly, and added to the reconstructed matrix in order to prevent the matrix from being singular. Compared with the conventional robust adaptive beamforming methods, the proposed method has improved performance and less computational complexity. Simulation results demonstrate the robustness and effectiveness of the proposed method.
This paper assumed stock price jump process for a special kind of renewal jump process,that is incident time interval for independent and subordinate to Gamma distribution random variable sequence.We obtain the European bi-direction option pricing formulas with jump diffusion model under the stochastic interest rates by simply mathematical induce by means of martingale method.
Abstract BackgroundAlthough treatment of diffuse large B-cell lymphoma (DLBCL) has progressed considerably in recent years, treatment failure still occurs in about 40% of patients who are refractory/relapse. Recent studies suggest that TP53 mutation may be an important cause of refractory/relapse in DLBCL, but the cause of TP53 mutation remains unclear. MethodsIn the present study, the correlation between TP53 mutation status and APOBEC3A and APOBEC3B expression in DLBCL specimens was searched by detecting the correlation between TP53 mutation and APOBEC3B expression in combination with database informatics analysis. Further, the relationship between APOBEC3B expression and TP53 mutation was analyzed by constructing APOBEC3B induced expression DLBCL cell lines. The effects of APOBEC3B-induced TP53 mutants on DLBCL cell proliferation and drug resistance were also tested. ResultsWe identify APOBEC3B as a critical factor that regulates p53-mutant driven drug resistance of DLBCL. APOBEC3B induces TP53 mutations of DLBCL cells, and its mutation patterns are similar to those in DLBCL patients. Moreover, APOBEC3B-induced p53 mutants promoted growth of DLBCL cells as well as contributed to drug resistance. In human DLBCL, APOBEC3B is aberrantly activated and associated with p53 mutant-mediated refractory/relapsed DLBCL. ConclusionThese findings yield insights into the mechanism of refractory/relapsed DLBCL induced by p53 mutants and reveal APOBEC3B as a new therapeutic target.
To improve the seismic performance of prestressed concrete solid square piles with a snap-in mechanical connection, effects of the prestressed tension control stress of PC steel rods, anchoring method and reinforcement ratio of hot-rolled steel bars on the seismic performance of the pile-cap joints in the prestressed concrete solid square piles using a snap-in mechanical connection were investigated in this article. Considering the above-mentioned effect factors, the quasi-static test was first carried out on the cap pile-cap joint specimens. Then, the seismic performance of the specimens was investigated. The results indicated that the yield load and ultimate load changed slightly, the displacement ductility increased, the stiffness decreased and the damage development rate slowed down as the prestressed tension control value decreased. When the prestressed tension control stress was reduced to 0.4 times of the standard value of tensile strength of the PC steel rods, the crack resistance moment could meet the requirements of construction and hoisting at the same time. In the process of pile cutting and anchoring, the 135° hook treatment on the end of the PC steel rods could reduce the strength degradation of the pile-cap joints during the loading process, improve the energy-dissipation capacity and slow down the damage development rate of the pile-cap joints. For the specimens with ordinary hot-rolled deformed steel bars added to the pile end, its ductility was improved, the horizontal bearing capacity, displacement ductility and energy dissipation capacity were all greatly improved, and the damage development rate was slowed down. However, the reinforcing ratio of the ordinary hot-rolled steel bars should be kept within a reasonable range. Finally, the improvement measures were proposed to improve the mechanical properties of the prestressed concrete solid square piles and pile-cap joints.
Abstract Abnormal change on the tongue is a potential complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT). The exact pathogenesis remains unclear and several risk factors include chemoradiotherapy, infection, graft-versus-host disease, disease relapse, and secondary malignancy. Our case described a 42-year-old woman with B-cell acute lymphoblastic leukemia treated by allo-HSCT 2 months later followed by a rare and atypical tongue neoplasia without oral pain, dysphagia, and dysgeusia. The biopsy was operated which showed granulation tissue with no evidence on typical graft-versus-host disease or malignancy, and no specific infection had been identified. Cyclosporine and mycophenolate mofetil, which were used for immunosuppression after allo-HSCT accompanying with the rapid growth of the tongue neoplasia, was then replaced by sirolimus. One month later, the patient underwent a complete remission unexpectedly.
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