BACKGROUND Among the various types of aortic dissection,multichanneled aortic dissection(MCAD)differs from classic double-channeled aortic dissection and involves the formation of an additional false lumen in the aort...BACKGROUND Among the various types of aortic dissection,multichanneled aortic dissection(MCAD)differs from classic double-channeled aortic dissection and involves the formation of an additional false lumen in the aortic wall or the flaps.It is considered a relatively rare condition with high perioperative mortality and morbidity.However,the morphological characteristic and the optimal therapeutic strategy for MCAD has not been fully determined.CASE SUMMARY A 64-year-old man presented to our hospital with severe epigastric abdominal pain radiating to the back that was associated with nausea without emesis.A computed tomography angiogram was performed that revealed a type B aortic dissection with multiple channels extending from the level of the left subclavian artery to the bilateral femoral arteries.We used a medical three-dimensional modeling(3D)modeling system to identify the location and extension of multiple lumens from different angles.It also precisely located the two primary entries leading to the false lumens,which helped us to exclude the two false lumens with one stent-graft.CONCLUSION By applying medical 3D modeling system,we discover the fragility of aortic wall and the collapse of true lumen caused by the multiple false lumens are the two morphological features of MCAD.展开更多
Neurons with complex-valued weights have stronger capability because of their multi-valued threshold logic. Neurons with such features may be suitable for solution of different kinds of problems including associative ...Neurons with complex-valued weights have stronger capability because of their multi-valued threshold logic. Neurons with such features may be suitable for solution of different kinds of problems including associative memory,image recognition and digital logical mapping. In this paper,robustness or tolerance is introduced and newly defined for this kind of neuron ac-cording to both their mathematical model and the perceptron neuron's definition of robustness. Also,the most robust design for basic digital logics of multiple variables is proposed based on these robust neurons. Our proof procedure shows that,in robust design each weight only takes the value of i or -i,while the value of threshold is with respect to the number of variables. The results demonstrate the validity and simplicity of using robust neurons for realizing arbitrary digital logical functions.展开更多
文摘BACKGROUND Among the various types of aortic dissection,multichanneled aortic dissection(MCAD)differs from classic double-channeled aortic dissection and involves the formation of an additional false lumen in the aortic wall or the flaps.It is considered a relatively rare condition with high perioperative mortality and morbidity.However,the morphological characteristic and the optimal therapeutic strategy for MCAD has not been fully determined.CASE SUMMARY A 64-year-old man presented to our hospital with severe epigastric abdominal pain radiating to the back that was associated with nausea without emesis.A computed tomography angiogram was performed that revealed a type B aortic dissection with multiple channels extending from the level of the left subclavian artery to the bilateral femoral arteries.We used a medical three-dimensional modeling(3D)modeling system to identify the location and extension of multiple lumens from different angles.It also precisely located the two primary entries leading to the false lumens,which helped us to exclude the two false lumens with one stent-graft.CONCLUSION By applying medical 3D modeling system,we discover the fragility of aortic wall and the collapse of true lumen caused by the multiple false lumens are the two morphological features of MCAD.
文摘Neurons with complex-valued weights have stronger capability because of their multi-valued threshold logic. Neurons with such features may be suitable for solution of different kinds of problems including associative memory,image recognition and digital logical mapping. In this paper,robustness or tolerance is introduced and newly defined for this kind of neuron ac-cording to both their mathematical model and the perceptron neuron's definition of robustness. Also,the most robust design for basic digital logics of multiple variables is proposed based on these robust neurons. Our proof procedure shows that,in robust design each weight only takes the value of i or -i,while the value of threshold is with respect to the number of variables. The results demonstrate the validity and simplicity of using robust neurons for realizing arbitrary digital logical functions.