In this paper, a theoretical and numerical study on the impact of a rubber solid on the free surface of a granular plate is presented, showing a simulation of an aircraft wheel on impact with a flexible landing surfac...In this paper, a theoretical and numerical study on the impact of a rubber solid on the free surface of a granular plate is presented, showing a simulation of an aircraft wheel on impact with a flexible landing surface. This physical action, when we use a theological approach, becomes a fundamental parameter to investigate wear and tear, and consequently strength to micro and macro pavements failure. The study has developed initially from a microscopic point of view and subsequently on macroscale. The effects are strictly linked with material degradation associated with damage evolution. The problem is developed by energetic approach on an elastic-plastic element using the functional energy containing two contributions, bulk and surface. The model simulates the behaviour of flexible runway pavements during the landing phase.展开更多
Acute coagulopathy of trauma-shock （ACoTS） occurs in 25% of patients with severe trauma in the early phase, and the mortality of those patients is four-fold higher than patients without coagulopathy. The pathophysio...Acute coagulopathy of trauma-shock （ACoTS） occurs in 25% of patients with severe trauma in the early phase, and the mortality of those patients is four-fold higher than patients without coagulopathy. The pathophysiology of this complicated phenomenon has been focused on in recent years. Tissue injury and hypoperfusion, activated protein C and Complements play important roles in the early phase after trauma. While the use of blood products, hypothermia, acidosis and inflammation are the main mechanism in late phase. Supplementing coagulation factors and platelets to improve ACoTS are inefficient. Only positive resuscitation from shock and improving tissue hypoperfusion have expected benefits.展开更多
Objective: To study the changes of the gene expression pattern of spinal cord tissues in the early stage after injury by DNA microarray (gene chip). Methods: The contusion model of rat spinal cord was established acco...Objective: To study the changes of the gene expression pattern of spinal cord tissues in the early stage after injury by DNA microarray (gene chip). Methods: The contusion model of rat spinal cord was established according to Allen’s falling strike method and the gene expression patterns of normal and injured spinal cord tissues were studied by gene chip. Results: The expression of 45 genes was significantly changed in the early stage after spinal cord injury, in which 22 genes up regulated and 23 genes down regulated. Conclusions: The expression of some genes changes significantly in the early stage after spinal cord injury, which indicates the complexity of secondary spinal cord injury.展开更多
文摘In this paper, a theoretical and numerical study on the impact of a rubber solid on the free surface of a granular plate is presented, showing a simulation of an aircraft wheel on impact with a flexible landing surface. This physical action, when we use a theological approach, becomes a fundamental parameter to investigate wear and tear, and consequently strength to micro and macro pavements failure. The study has developed initially from a microscopic point of view and subsequently on macroscale. The effects are strictly linked with material degradation associated with damage evolution. The problem is developed by energetic approach on an elastic-plastic element using the functional energy containing two contributions, bulk and surface. The model simulates the behaviour of flexible runway pavements during the landing phase.
文摘Acute coagulopathy of trauma-shock （ACoTS） occurs in 25% of patients with severe trauma in the early phase, and the mortality of those patients is four-fold higher than patients without coagulopathy. The pathophysiology of this complicated phenomenon has been focused on in recent years. Tissue injury and hypoperfusion, activated protein C and Complements play important roles in the early phase after trauma. While the use of blood products, hypothermia, acidosis and inflammation are the main mechanism in late phase. Supplementing coagulation factors and platelets to improve ACoTS are inefficient. Only positive resuscitation from shock and improving tissue hypoperfusion have expected benefits.
文摘Objective: To study the changes of the gene expression pattern of spinal cord tissues in the early stage after injury by DNA microarray (gene chip). Methods: The contusion model of rat spinal cord was established according to Allen’s falling strike method and the gene expression patterns of normal and injured spinal cord tissues were studied by gene chip. Results: The expression of 45 genes was significantly changed in the early stage after spinal cord injury, in which 22 genes up regulated and 23 genes down regulated. Conclusions: The expression of some genes changes significantly in the early stage after spinal cord injury, which indicates the complexity of secondary spinal cord injury.
