由于外在因素导致出土的文物模型呈现破碎状态,对其进行虚拟修复对考古学具有重要意义。现有孔洞修补方法大多仅针对三维模型结构进行补全,并且在三维结构修复后缺少表面的颜色纹理信息。本文基于文物三维空间结构和纹理信息,提出一种...由于外在因素导致出土的文物模型呈现破碎状态,对其进行虚拟修复对考古学具有重要意义。现有孔洞修补方法大多仅针对三维模型结构进行补全,并且在三维结构修复后缺少表面的颜色纹理信息。本文基于文物三维空间结构和纹理信息,提出一种三维文物孔洞修复方法。首先,为了解决三维文物结构修复问题,利用基于径向基函数的算法填补三维文物网格模型的孔洞,通过拟合的曲面方程调整孔洞补丁顶点,使其与原有模型更好地融合。其次,为补全文物表面颜色纹理信息,使孔洞补丁与原有模型表面纹理自然过渡,将三维问题转化为二维图像修复问题,以EdgeConnect为框架,通过添加精细化网络生成更高分辨率的结果。最后,使用Mudbox软件映射二维图像到三维模型表面,融合结构和纹理修复的结果。本文改进后的二维修复网络在评价指标PSNR(Peak Signal to Noise Ratio)、SSIM(Structural Similarity)和MAE(Mean Absolute Deviation)的性能分别提高了0.54%、0.217%和6.52%,该方法能够有效地恢复兵马俑三维模型网格结构和表面纹理信息。展开更多
The symmetric dynamical model of a Cournot duopoly based on conjectural variation is established.Local stability of the equilibrium point is analyzed and the invariant sets are given.Then,dynamic behavior is studied b...The symmetric dynamical model of a Cournot duopoly based on conjectural variation is established.Local stability of the equilibrium point is analyzed and the invariant sets are given.Then,dynamic behavior is studied by numerical simulation.With the change of gradient adjustment parameters,the routes to chaos vary.Synchronization occurs along the invariant sets accompanied by the on-off intermittency through the analysis of transverse stability.Coexistence of multiple attractors and structure of basins of attraction being more complex indicate more complicated bifurcation phenomena.展开更多
Disturbance of the cholinergic system plays a crucial role in the pathological progression of neurological diseases that cause dyskinesia-like behaviors.However,the molecular mechanisms underlying this disturbance rem...Disturbance of the cholinergic system plays a crucial role in the pathological progression of neurological diseases that cause dyskinesia-like behaviors.However,the molecular mechanisms underlying this disturbance remain elusive.Here,we showed that cyclin-dependent kinase 5(Cdk5)was reduced in cholinergic neurons of midbrain according to the single-nucleus RNA sequencing analysis.Serum levels of CDK5 also decreased in patients with Parkinson’s disease accompanied by motor symptoms.Moreover,Cdk5 deficiency in cholinergic neurons triggered paw tremors,abnormal motor coordination,and motor balance deficits in mice.These symptoms occurred along with cholinergic neuron hyperexcitability and increases in the current density of large-conductance Ca2+-activated K+channels(BK channels).Pharmacological inhibition of BK channels restrained the excessive intrinsic excitability of striatal cholinergic neurons in Cdk5-deficient mice.Furthermore,CDK5 interacted with BK channels and negatively regulated BK channel activity via phosphorylation of threonine-908.Restoration of CDK5 expression in striatal cholinergic neurons reduced dyskinesia-like behaviors in ChAT-Cre;Cdk5f/f mice.Together,these findings indicate that CDK5-induced phosphorylation of BK channels involves in cholinergic-neuronmediated motor function,providing a potential new therapeutic target for treating dyskinesia-like behaviors arising from neurological diseases.展开更多
文摘由于外在因素导致出土的文物模型呈现破碎状态,对其进行虚拟修复对考古学具有重要意义。现有孔洞修补方法大多仅针对三维模型结构进行补全,并且在三维结构修复后缺少表面的颜色纹理信息。本文基于文物三维空间结构和纹理信息,提出一种三维文物孔洞修复方法。首先,为了解决三维文物结构修复问题,利用基于径向基函数的算法填补三维文物网格模型的孔洞,通过拟合的曲面方程调整孔洞补丁顶点,使其与原有模型更好地融合。其次,为补全文物表面颜色纹理信息,使孔洞补丁与原有模型表面纹理自然过渡,将三维问题转化为二维图像修复问题,以EdgeConnect为框架,通过添加精细化网络生成更高分辨率的结果。最后,使用Mudbox软件映射二维图像到三维模型表面,融合结构和纹理修复的结果。本文改进后的二维修复网络在评价指标PSNR(Peak Signal to Noise Ratio)、SSIM(Structural Similarity)和MAE(Mean Absolute Deviation)的性能分别提高了0.54%、0.217%和6.52%,该方法能够有效地恢复兵马俑三维模型网格结构和表面纹理信息。
基金National Natural Science Foundation of China(Nos.11962011,61463027)Humanities and Social Sciences from the Ministry of Education of China(No.15YJC820007)。
文摘The symmetric dynamical model of a Cournot duopoly based on conjectural variation is established.Local stability of the equilibrium point is analyzed and the invariant sets are given.Then,dynamic behavior is studied by numerical simulation.With the change of gradient adjustment parameters,the routes to chaos vary.Synchronization occurs along the invariant sets accompanied by the on-off intermittency through the analysis of transverse stability.Coexistence of multiple attractors and structure of basins of attraction being more complex indicate more complicated bifurcation phenomena.
基金This work was supported by the National Key Research and Development Program of China(2022YFE0108600)the State Key Program of National Natural Science Foundations of China(81930103)the National Natural Science Foundations of China(81973300,82104162,and 82171249).
文摘Disturbance of the cholinergic system plays a crucial role in the pathological progression of neurological diseases that cause dyskinesia-like behaviors.However,the molecular mechanisms underlying this disturbance remain elusive.Here,we showed that cyclin-dependent kinase 5(Cdk5)was reduced in cholinergic neurons of midbrain according to the single-nucleus RNA sequencing analysis.Serum levels of CDK5 also decreased in patients with Parkinson’s disease accompanied by motor symptoms.Moreover,Cdk5 deficiency in cholinergic neurons triggered paw tremors,abnormal motor coordination,and motor balance deficits in mice.These symptoms occurred along with cholinergic neuron hyperexcitability and increases in the current density of large-conductance Ca2+-activated K+channels(BK channels).Pharmacological inhibition of BK channels restrained the excessive intrinsic excitability of striatal cholinergic neurons in Cdk5-deficient mice.Furthermore,CDK5 interacted with BK channels and negatively regulated BK channel activity via phosphorylation of threonine-908.Restoration of CDK5 expression in striatal cholinergic neurons reduced dyskinesia-like behaviors in ChAT-Cre;Cdk5f/f mice.Together,these findings indicate that CDK5-induced phosphorylation of BK channels involves in cholinergic-neuronmediated motor function,providing a potential new therapeutic target for treating dyskinesia-like behaviors arising from neurological diseases.
