The thermal quantum discord （QD） is studied in a two-qubit Heisenberg XXZ system with DzyaloshinskiiMoriya （DM） interaction. We compare the thermal QD with thermal entanglement in this system and find remarkable d...The thermal quantum discord （QD） is studied in a two-qubit Heisenberg XXZ system with DzyaloshinskiiMoriya （DM） interaction. We compare the thermal QD with thermal entanglement in this system and find remarkable differences between them. For instance, we show situations where QD decreases asymptotically to zero with temperature T while entanglement decreases to zero at the point of critical temperature, situations where QD decreases with certain tunable parameters such as Dx and Dx when entanglement increases. We find that the characteristic of QD is exotic in this system and this possibly offers a potential solution to enhance entanglement of a system. We also show that tunable parameter Dx is more efficient than parameter Dz in most regions for controlling the QD.展开更多
Objective: To investigate the characteristics of bone fractures from road traffic accidents and analyze their injury mechanisms so as to provide reference for the research and medical care of traffic trauma. Methods: ...Objective: To investigate the characteristics of bone fractures from road traffic accidents and analyze their injury mechanisms so as to provide reference for the research and medical care of traffic trauma. Methods: Three hundred and six patients with fractures from road traffic accidents were included into this study. A total of 507 fractures were identified and the injury mechanism, location distribution and frequency were analyzed. Results: The most common location of fractures was the lower extremities, followed by the upper extremities, skull and maxillofacial region, and the rarest was the spine. A total of 56% of the patients suffered from multiple fractures. The fractures of the patella, femur and pelvis and the fractures of the olecranon, humerus and shoulder often happened simultaneously. Conclusions: The injury mechanisms can be classified into four types: impact, incoordinate movement, stretch injury and crush and extrusion. The fractures from traffic accidents have the following characteristics: centrifugal distribution of the injuries, multiple fractures, force transmission and ipsilateral occurrence.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos.90503009,10775116973 Program under Grant No.2005CB724508
文摘The thermal quantum discord （QD） is studied in a two-qubit Heisenberg XXZ system with DzyaloshinskiiMoriya （DM） interaction. We compare the thermal QD with thermal entanglement in this system and find remarkable differences between them. For instance, we show situations where QD decreases asymptotically to zero with temperature T while entanglement decreases to zero at the point of critical temperature, situations where QD decreases with certain tunable parameters such as Dx and Dx when entanglement increases. We find that the characteristic of QD is exotic in this system and this possibly offers a potential solution to enhance entanglement of a system. We also show that tunable parameter Dx is more efficient than parameter Dz in most regions for controlling the QD.
文摘Objective: To investigate the characteristics of bone fractures from road traffic accidents and analyze their injury mechanisms so as to provide reference for the research and medical care of traffic trauma. Methods: Three hundred and six patients with fractures from road traffic accidents were included into this study. A total of 507 fractures were identified and the injury mechanism, location distribution and frequency were analyzed. Results: The most common location of fractures was the lower extremities, followed by the upper extremities, skull and maxillofacial region, and the rarest was the spine. A total of 56% of the patients suffered from multiple fractures. The fractures of the patella, femur and pelvis and the fractures of the olecranon, humerus and shoulder often happened simultaneously. Conclusions: The injury mechanisms can be classified into four types: impact, incoordinate movement, stretch injury and crush and extrusion. The fractures from traffic accidents have the following characteristics: centrifugal distribution of the injuries, multiple fractures, force transmission and ipsilateral occurrence.
