Reflection imaging results generally reveal large-scale continuous geological information,and it is difficult to identify small-scale geological bodies such as breakpoints,pinch points,small fault blocks,caves,and fra...Reflection imaging results generally reveal large-scale continuous geological information,and it is difficult to identify small-scale geological bodies such as breakpoints,pinch points,small fault blocks,caves,and fractures,etc.Diffraction imaging is an important method to identify small-scale geological bodies and it has higher resolution than reflection imaging.In the common-offset domain,reflections are mostly expressed as smooth linear events,whereas diffractions are characterized by hyperbolic events.This paper proposes a diffraction extraction method based on double sparse transforms.The linear events can be sparsely expressed by the high-resolution linear Radon transform,and the curved events can be sparsely expressed by the Curvelet transform.A sparse inversion model is built and the alternating direction method is used to solve the inversion model.Simulation data and field data experimental results proved that the diffractions extraction method based on double sparse transforms can effectively improve the imaging quality of faults and other small-scale geological bodies.展开更多
Purpose:Treatment of irreducible femoral intertrochanteric fractures often requires open reduction.However,the technique unavoidably causes patients to suffer greater trauma.As such,minimally invasive techniques shoul...Purpose:Treatment of irreducible femoral intertrochanteric fractures often requires open reduction.However,the technique unavoidably causes patients to suffer greater trauma.As such,minimally invasive techniques should be employed to reduce the surgical-related trauma on these patients and maintain a stable reduction of the fractures.Herein,a minimally invasive wire introducer was designed and used for the treatment of femoral intertrochanteric fractures.The effectiveness of using a wireguided device to treat irreducible femoral intertrochanteric fractures was evaluated.Methods:Between 2013 and 2018,patients with femoral intertrochanteric fractures who were initially treated by intramedullary nail fixation but had difficult reduction using the traction beds were retrospectively reviewed.Decision for an additional surgery was based on the displacement of the fracture.The patients were then divided into two groups:those in the control group received an open reduction surgery while those in the observation group received a closed reduction surgery using a minimally invasive wire introducer to guide the wire that could assist in fracture reduction.The operation time,blood loss,visual analogue scale scores,angulation,reduction,neck-shaft angle,re-displacement,limb length discrepancy,and union time were then recorded and analyzed to determine the efficiency of the wire introducer technique.Categorical variables were analyzed by using Chi-square test,while continuous variables by independent t-test and the Mann-Whitney test accordingly.Results:There were 92 patients included in this study:61 in the control group and 31 in the observation group.There were no significant differences in baseline demographic factors between the two groups.All surgeries were successful with no deaths within the perioperative period.The average follow-up time for the patients was 23.8 months.However,the observation group had a significantly shorter operation time,lower visual analogue scale score,less intraoperative bleeding,and shorter fracture healing time.There were no significant differences in the angulation,reduction,neck-shaft angle,and limb length discrepancy between the two groups.Conclusion:The minimally invasive wire guide achieved a similar effect to that of open reduction in the treatment of intertrochanteric fractures with difficult reduction.Moreover,the minimally invasive wire introducer is a good technology that accurately guides the wire during reduction.Indeed,it is an effective technique and achieves good clinical outcomes in restoration of irreducible femoral intertrochanteric fractures.展开更多
基金supported by National Natural Science Foundation of China(41974166)Natural Science Foundation of Hebei Province(D2019403082,D2021403010)+1 种基金Hebei Province“three-threethree talent project”(A202005009)Funding for the Science and Technology Innovation Team Project of Hebei GEO University(KJCXTD202106)
文摘Reflection imaging results generally reveal large-scale continuous geological information,and it is difficult to identify small-scale geological bodies such as breakpoints,pinch points,small fault blocks,caves,and fractures,etc.Diffraction imaging is an important method to identify small-scale geological bodies and it has higher resolution than reflection imaging.In the common-offset domain,reflections are mostly expressed as smooth linear events,whereas diffractions are characterized by hyperbolic events.This paper proposes a diffraction extraction method based on double sparse transforms.The linear events can be sparsely expressed by the high-resolution linear Radon transform,and the curved events can be sparsely expressed by the Curvelet transform.A sparse inversion model is built and the alternating direction method is used to solve the inversion model.Simulation data and field data experimental results proved that the diffractions extraction method based on double sparse transforms can effectively improve the imaging quality of faults and other small-scale geological bodies.
文摘Purpose:Treatment of irreducible femoral intertrochanteric fractures often requires open reduction.However,the technique unavoidably causes patients to suffer greater trauma.As such,minimally invasive techniques should be employed to reduce the surgical-related trauma on these patients and maintain a stable reduction of the fractures.Herein,a minimally invasive wire introducer was designed and used for the treatment of femoral intertrochanteric fractures.The effectiveness of using a wireguided device to treat irreducible femoral intertrochanteric fractures was evaluated.Methods:Between 2013 and 2018,patients with femoral intertrochanteric fractures who were initially treated by intramedullary nail fixation but had difficult reduction using the traction beds were retrospectively reviewed.Decision for an additional surgery was based on the displacement of the fracture.The patients were then divided into two groups:those in the control group received an open reduction surgery while those in the observation group received a closed reduction surgery using a minimally invasive wire introducer to guide the wire that could assist in fracture reduction.The operation time,blood loss,visual analogue scale scores,angulation,reduction,neck-shaft angle,re-displacement,limb length discrepancy,and union time were then recorded and analyzed to determine the efficiency of the wire introducer technique.Categorical variables were analyzed by using Chi-square test,while continuous variables by independent t-test and the Mann-Whitney test accordingly.Results:There were 92 patients included in this study:61 in the control group and 31 in the observation group.There were no significant differences in baseline demographic factors between the two groups.All surgeries were successful with no deaths within the perioperative period.The average follow-up time for the patients was 23.8 months.However,the observation group had a significantly shorter operation time,lower visual analogue scale score,less intraoperative bleeding,and shorter fracture healing time.There were no significant differences in the angulation,reduction,neck-shaft angle,and limb length discrepancy between the two groups.Conclusion:The minimally invasive wire guide achieved a similar effect to that of open reduction in the treatment of intertrochanteric fractures with difficult reduction.Moreover,the minimally invasive wire introducer is a good technology that accurately guides the wire during reduction.Indeed,it is an effective technique and achieves good clinical outcomes in restoration of irreducible femoral intertrochanteric fractures.