Objective To investigate the clinical outcome of humeral head replacement and individualized rehabilitation for displaced four-part fractures of proximal humerus,to provide clinical guideline of treating complicated f...Objective To investigate the clinical outcome of humeral head replacement and individualized rehabilitation for displaced four-part fractures of proximal humerus,to provide clinical guideline of treating complicated fractures of展开更多
AIM： To investigate clinical efficacy of displaced intra-articular calcaneal fracture （DIACF） following operation and nonoperation. METHODS： Literature search was performed of PubMed and Cochrane Library by two in...AIM： To investigate clinical efficacy of displaced intra-articular calcaneal fracture （DIACF） following operation and nonoperation. METHODS： Literature search was performed of PubMed and Cochrane Library by two independent authors to identify randomized controlled trials （RCTs） comparing operative vs nonoperative treatment of DIACF from inception to December 31st, 2013. RCT quality was evaluated by the modified Jadad scale. Dichotomous variables were pooled using risk ratios by review manager 5.3 software. Fixed-effects or random-effects models were adopted with P 〉 0.05 or P ≤ 0.05 for heterogeneity tests, respectively.RESULTS： Eight RCTs comprising 767 cases met inclusion criteria. Results revealed that more surgically treated patients could resume pre-injury job （P = 0.006）. No statistical differences were found between the two groups in residual pain （P = 0.33）, shoe fitting problems （P = 0.07）, limited walking distance （P = 0.56） or secondary late arthrodesis （P = 0.38）. However, operative treatment was associated with a higher complication rate （P = 0.003）. Subgroup analyses of specific complications revealed that except for a higher risk of superficial wound problems （P 〈 0.0001） in operative group, the two groups had similar complication rate in deep wound infection （ P = 0.34）,CONCLUSION： Current evidence demonstrates that compared with operative treatment, conservative treatment of DIACF lead to similar clinical outcomes regarding residual pain, shoe fitting, walking distance and secondary subtalar arthrodesis but a significantly lower complication rate.展开更多
Considering the adsorption loss of the hydraulic fracturing assisted oil displacement(HFAD)agent in the matrix,a method is proposed to characterize the dynamic saturation adsorption capacity of the HFAD agent with pre...Considering the adsorption loss of the hydraulic fracturing assisted oil displacement(HFAD)agent in the matrix,a method is proposed to characterize the dynamic saturation adsorption capacity of the HFAD agent with pressure differential and permeability.Coupled with the viscosity-concentration relationship of the HFAD agent,a non-linear seepage model of HFAD was established,taking into account the adsorption effect of high pressure drops,and the influencing factors were analyzed.The findings indicate that the replenishment of formation energy associated with HFAD technology is predominantly influenced by matrix permeability,fracture length and the initial concentration of the HFAD agent.The effect of replenishment of formation energy is positively correlated with matrix permeability and fracture length,and negatively correlated with the initial concentration of the HFAD agent.The initial concentration and injection amount of the high-pressure HFAD agent can enhance the concentration of the HFAD agent in the matrix and improve the efficiency of oil washing.However,a longer fracture is not conducive to maintaining the high concentration of the HFAD agent in the matrix.Furthermore,the fracture length and pump displacement are the direct factors affecting the fluid flow velocity in the matrix subsequent to HFAD.These factors can be utilized to control the location of the displacement phase front,and thus affect the swept area of HFAD.A reasonable selection of the aforementioned parameters can effectively supplement the formation energy,expand the swept volume of the HFAD agent,improve the recovery efficiency of HFAD,and reduce the development cost.展开更多
Purpose： To compare the efficacy and safety of open reduction and internal fixation through ilioinguinal approach and Stoppa approach for the treatment of displaced acetabular fractures. Methods： Case-controlled tri...Purpose： To compare the efficacy and safety of open reduction and internal fixation through ilioinguinal approach and Stoppa approach for the treatment of displaced acetabular fractures. Methods： Case-controlled trials （CCTs） published from January 2010 to August 2015 that compared the ilioinguinal approach and Stoppa approach in the management of displaced acetabular fractures were retrieved from the databases of Cochrane Library, Pubmed, CNKI, and so on. Methodological quality of the trials was critically assessed. Statistical software RevMan 5.0 was used for data analysis. Results： Eight articles were included in the meta-analysis. Through comparing the efficacy and safety of ilioinguinal approach and Stoppa approach in the treatment of displaced acetabular fracture, statistical significance was found in the average operation time [WMD = 68.29, 95% CI （10.52, 126.05）, p 〈 0.05] and the median intraoperative blood loss [WMD = 142.26, 95% CI （9.30, 275.23）, p 〈 0.05]. However, there existed no statistical significance in the fracture end reset satisfaction rate [RR = 0.63, 95% CI （0.17, 2.37）, p 〉 0.05], the early complications rate [RR = 0.89, 95% CI （0.33, 2.40）, p 〉 0.05], the late complications rate [RR = 0.91, 95% CI （0.27, 3.01）, p 〉 0.05], and Harris hip score good function rate [RR = 0.52, 95% CI （0.25, 1.10）, p 〉 0.05]. Conclusion： Though both techniques can obtain satisfactory clinical functions in the treatment of displaced acetabular fractures, Stoppa approach is superior to the ilioinguinal approach in terms of operation time and intraoperative blood loss.展开更多
The recently developed European flaw assessment procedure, structural integrity assessment procedure（SiNTAP） is applied to assessment for welded joints of the API 5L X65 pipeline steel with an assumed embedded flaw ...The recently developed European flaw assessment procedure, structural integrity assessment procedure（SiNTAP） is applied to assessment for welded joints of the API 5L X65 pipeline steel with an assumed embedded flaw and surface flaw at the weld toe. As one of the basic input data, fracture toughness crack tip opening displacement （CTOD） tests are conducted at 0℃ and performed according to the requirements of the standard of BS7448. For the heat affected zone （HAZ） specimens, the microstructure observation is performed to insure that the tip of the crack is located in the coarse grain zone. The result explains the dispersity of the test values. In structural integrity assessment procedure-fracture assessment diagram（SINTAP FAD） method, the failure curves of welded joints at level 1 and 3 are derived from the tensile test results. The results of the assessment show that all assessment points are located within the failure lines of analysis level 1 and 3. So the welded joint of the pipeline is safe. This study laid the foundation of application of SINTAP to pipeline structure assessment.展开更多
This paper comprehensively reviews the application and research progress of CO_(2) fracturing fluids in China,highlights the existing issues and puts forward suggestions for future development.Three types of fracturin...This paper comprehensively reviews the application and research progress of CO_(2) fracturing fluids in China,highlights the existing issues and puts forward suggestions for future development.Three types of fracturing fluid systems containing CO_(2),namely,CO_(2) dry fracturing fluid,CO_(2) energized fracturing fluid,and CO_(2) foam fracturing fluid,are categorized based on the mass ratio and process difference between CO_(2),water,and treatment agents.Field applications in China reveal several problem to be resolved:(1)The application scope of CO_(2) fracturing fluids is restricted to depleted reservoirs,re-fracturing of old wells,and medium-deep reservoirs with low formation pressure coefficients;(2)different types of CO_(2) fracturing fluids require different processes and ground supporting equipment;(3)optimization of CO_(2) compatibility,functionality,temperature and salt tolerance,as well as the cost of treatment agents is necessitated;(4)existing CO_(2) fracturing fluid system fail to perform well with low friction,low filtration,and high sand-carrying capacity.(5)there lacks a targeted industry standard for evaluation of performance of CO_(2) fracturing fluid system and treatment agents.Therefore,in order to meet the goals of CCUS-EOR,CCUS-EGR,or integration of fracturing,displacement and burial by CO_(2),efforts should be made in the aspects that followed,including in-depth investigation of the mechanism of CO_(2) fracturing fluids,the adaptability and compatibility between existing equipment,different CO_(2) fracturing fluid systems and processes,and construction of treatment agents,low-density proppants and highperformance systems of recyclability and industrial-grade.In addition,optimization of CO_(2) fracturing fluid system based fracturing design is also crucial taking such related factors such as overall reservoir geological conditions,petrophysical properties,CO_(2) transportation,and well site layout into consideration.展开更多
文摘Objective To investigate the clinical outcome of humeral head replacement and individualized rehabilitation for displaced four-part fractures of proximal humerus,to provide clinical guideline of treating complicated fractures of
文摘AIM： To investigate clinical efficacy of displaced intra-articular calcaneal fracture （DIACF） following operation and nonoperation. METHODS： Literature search was performed of PubMed and Cochrane Library by two independent authors to identify randomized controlled trials （RCTs） comparing operative vs nonoperative treatment of DIACF from inception to December 31st, 2013. RCT quality was evaluated by the modified Jadad scale. Dichotomous variables were pooled using risk ratios by review manager 5.3 software. Fixed-effects or random-effects models were adopted with P 〉 0.05 or P ≤ 0.05 for heterogeneity tests, respectively.RESULTS： Eight RCTs comprising 767 cases met inclusion criteria. Results revealed that more surgically treated patients could resume pre-injury job （P = 0.006）. No statistical differences were found between the two groups in residual pain （P = 0.33）, shoe fitting problems （P = 0.07）, limited walking distance （P = 0.56） or secondary late arthrodesis （P = 0.38）. However, operative treatment was associated with a higher complication rate （P = 0.003）. Subgroup analyses of specific complications revealed that except for a higher risk of superficial wound problems （P 〈 0.0001） in operative group, the two groups had similar complication rate in deep wound infection （ P = 0.34）,CONCLUSION： Current evidence demonstrates that compared with operative treatment, conservative treatment of DIACF lead to similar clinical outcomes regarding residual pain, shoe fitting, walking distance and secondary subtalar arthrodesis but a significantly lower complication rate.
基金Supported by the National Nature Science Foundation of China(52374035,52074087)Postdoctoral Natural Science Foundation of China(2021M690528)。
文摘Considering the adsorption loss of the hydraulic fracturing assisted oil displacement(HFAD)agent in the matrix,a method is proposed to characterize the dynamic saturation adsorption capacity of the HFAD agent with pressure differential and permeability.Coupled with the viscosity-concentration relationship of the HFAD agent,a non-linear seepage model of HFAD was established,taking into account the adsorption effect of high pressure drops,and the influencing factors were analyzed.The findings indicate that the replenishment of formation energy associated with HFAD technology is predominantly influenced by matrix permeability,fracture length and the initial concentration of the HFAD agent.The effect of replenishment of formation energy is positively correlated with matrix permeability and fracture length,and negatively correlated with the initial concentration of the HFAD agent.The initial concentration and injection amount of the high-pressure HFAD agent can enhance the concentration of the HFAD agent in the matrix and improve the efficiency of oil washing.However,a longer fracture is not conducive to maintaining the high concentration of the HFAD agent in the matrix.Furthermore,the fracture length and pump displacement are the direct factors affecting the fluid flow velocity in the matrix subsequent to HFAD.These factors can be utilized to control the location of the displacement phase front,and thus affect the swept area of HFAD.A reasonable selection of the aforementioned parameters can effectively supplement the formation energy,expand the swept volume of the HFAD agent,improve the recovery efficiency of HFAD,and reduce the development cost.
基金This study was funded by the National Natural Science Foundation of China {No.81572098） and Natural Science Foundation of Shanxi Province of China （No. 2008012011-3）.
文摘Purpose： To compare the efficacy and safety of open reduction and internal fixation through ilioinguinal approach and Stoppa approach for the treatment of displaced acetabular fractures. Methods： Case-controlled trials （CCTs） published from January 2010 to August 2015 that compared the ilioinguinal approach and Stoppa approach in the management of displaced acetabular fractures were retrieved from the databases of Cochrane Library, Pubmed, CNKI, and so on. Methodological quality of the trials was critically assessed. Statistical software RevMan 5.0 was used for data analysis. Results： Eight articles were included in the meta-analysis. Through comparing the efficacy and safety of ilioinguinal approach and Stoppa approach in the treatment of displaced acetabular fracture, statistical significance was found in the average operation time [WMD = 68.29, 95% CI （10.52, 126.05）, p 〈 0.05] and the median intraoperative blood loss [WMD = 142.26, 95% CI （9.30, 275.23）, p 〈 0.05]. However, there existed no statistical significance in the fracture end reset satisfaction rate [RR = 0.63, 95% CI （0.17, 2.37）, p 〉 0.05], the early complications rate [RR = 0.89, 95% CI （0.33, 2.40）, p 〉 0.05], the late complications rate [RR = 0.91, 95% CI （0.27, 3.01）, p 〉 0.05], and Harris hip score good function rate [RR = 0.52, 95% CI （0.25, 1.10）, p 〉 0.05]. Conclusion： Though both techniques can obtain satisfactory clinical functions in the treatment of displaced acetabular fractures, Stoppa approach is superior to the ilioinguinal approach in terms of operation time and intraoperative blood loss.
基金This project is supported by National Natural Science Foundation of China(No.50375109).
文摘The recently developed European flaw assessment procedure, structural integrity assessment procedure（SiNTAP） is applied to assessment for welded joints of the API 5L X65 pipeline steel with an assumed embedded flaw and surface flaw at the weld toe. As one of the basic input data, fracture toughness crack tip opening displacement （CTOD） tests are conducted at 0℃ and performed according to the requirements of the standard of BS7448. For the heat affected zone （HAZ） specimens, the microstructure observation is performed to insure that the tip of the crack is located in the coarse grain zone. The result explains the dispersity of the test values. In structural integrity assessment procedure-fracture assessment diagram（SINTAP FAD） method, the failure curves of welded joints at level 1 and 3 are derived from the tensile test results. The results of the assessment show that all assessment points are located within the failure lines of analysis level 1 and 3. So the welded joint of the pipeline is safe. This study laid the foundation of application of SINTAP to pipeline structure assessment.
基金support for this work from National Natural Science Foundation of China (Grants No,U21B2071).
文摘This paper comprehensively reviews the application and research progress of CO_(2) fracturing fluids in China,highlights the existing issues and puts forward suggestions for future development.Three types of fracturing fluid systems containing CO_(2),namely,CO_(2) dry fracturing fluid,CO_(2) energized fracturing fluid,and CO_(2) foam fracturing fluid,are categorized based on the mass ratio and process difference between CO_(2),water,and treatment agents.Field applications in China reveal several problem to be resolved:(1)The application scope of CO_(2) fracturing fluids is restricted to depleted reservoirs,re-fracturing of old wells,and medium-deep reservoirs with low formation pressure coefficients;(2)different types of CO_(2) fracturing fluids require different processes and ground supporting equipment;(3)optimization of CO_(2) compatibility,functionality,temperature and salt tolerance,as well as the cost of treatment agents is necessitated;(4)existing CO_(2) fracturing fluid system fail to perform well with low friction,low filtration,and high sand-carrying capacity.(5)there lacks a targeted industry standard for evaluation of performance of CO_(2) fracturing fluid system and treatment agents.Therefore,in order to meet the goals of CCUS-EOR,CCUS-EGR,or integration of fracturing,displacement and burial by CO_(2),efforts should be made in the aspects that followed,including in-depth investigation of the mechanism of CO_(2) fracturing fluids,the adaptability and compatibility between existing equipment,different CO_(2) fracturing fluid systems and processes,and construction of treatment agents,low-density proppants and highperformance systems of recyclability and industrial-grade.In addition,optimization of CO_(2) fracturing fluid system based fracturing design is also crucial taking such related factors such as overall reservoir geological conditions,petrophysical properties,CO_(2) transportation,and well site layout into consideration.
