Bone defect repairs are based on bone graft fusion or replacement.Current large bone defect treatments are inadequate and lack of reliable technology.Therefore,we aimed to investigate a simple technique using three-di...Bone defect repairs are based on bone graft fusion or replacement.Current large bone defect treatments are inadequate and lack of reliable technology.Therefore,we aimed to investigate a simple technique using three-dimensional(3D)-printed individualized porous implants without any bone grafts,osteoinductive agents,or surface biofunctionalization to treat large bone defects,and systematically study its long-term therapeutic effects and osseointegration characteristics.Twenty-six patients with large bone defects caused by tumor,infection,or trauma received treatment with individualized porous implants;among them,three typical cases underwent a detailed study.Additionally,a large segmental femur defect sheep model was used to study the osseointegration characteristics.Immediate and long-term biomechanical stability was achieved,and the animal study revealed that the bone grew into the pores with gradual remodeling,resulting in a long-term mechanically stable implant-bone complex.Advantages of 3D-printed microporous implants for the repair of bone defects included 1)that the stabilization devices were immediately designed and constructed to achieve early postoperative mobility,and 2)that osseointegration between the host bone and implants was achieved without bone grafting.Our osseointegration method,in which the“implant-bone”interface fusion concept was used instead of“bone-bone”fusion,subverts the traditional idea of osseointegration.展开更多
Newly built tunnels often encounter a series of defects within the first few years of operation.If not promptly addressed and reinforced,these defects threaten the tunnel's durability and stability and bring sever...Newly built tunnels often encounter a series of defects within the first few years of operation.If not promptly addressed and reinforced,these defects threaten the tunnel's durability and stability and bring severe challenges to its safe operation.This study aims to explore reinforcement techniques for addressing defects in newly built tunnels.The research begins with an analysis of common defects found in newly built tunnels,followed by a case study of the Jinfeng Tunnel in Chongqing,examining the post-construction defects.The actual reinforcement strategies and methods employed for the tunnel are then discussed.Finally,based on the research findings,this study provides insights and references for tunnel operation and construction units in China,aiming to enhance the overall quality of tunnel engineering in the country,align with sustainable development goals,and promote further improvements at a macro level.展开更多
Jinping I hydropower station is one of the most challenging projects in China due to its highest arch dam and complex geological conditions for construction.After geological investigation into the dam foundation,a few...Jinping I hydropower station is one of the most challenging projects in China due to its highest arch dam and complex geological conditions for construction.After geological investigation into the dam foundation,a few large-scale weak discontinuities are observed.The rock masses in the left dam foundation are intensively unloaded,approximately to the depth of 150–300 m.These serious geological defects lead to a geological asymmetry on the left and right banks,and thus some major diffculties of dam construction are encountered.In this paper,the influences of geological defects on the project are analyzed,followed by the concepts and methods of treatment design.Based on the analysis,the treatment methods of the weak rock masses and discontinuities are carefully determined,including the concrete cushion,concrete replacement grids,and consolidation grouting.They work together to enhance the strength and integrity of the dam foundation.Evaluations and calibrations through geo-mechanical model tests in combination with feld monitoring results in early impoundment period show that the arch dam and its foundation are roughly stable,suggesting that the treatment designs are reasonable and effective.The proposed treatment methods and concepts in the context can be helpful for similar complex rock projects.展开更多
A direct strategy for the creation of defects on carbon nanofibers (CNFs) has been developed by steam treatment.Nitrogen physisorption,XRD,Raman spectra,SEM and TEM analyses proved the existence of the new defects on ...A direct strategy for the creation of defects on carbon nanofibers (CNFs) has been developed by steam treatment.Nitrogen physisorption,XRD,Raman spectra,SEM and TEM analyses proved the existence of the new defects on CNFs.BET surface area of CNFs after steam treatment was enhanced from 20 to 378 m2/g.Pd catalysts supported on CNFs were also prepared by colloidal deposition method.The different activity of Pd/CNFs catalysts in the partial hydrogenation of phenylacetylene further demonstrated the diverse surfaces of CNFs could be formed by steam treatment.展开更多
In the present paper, 32 cases of cutaneous defect were treated by using warm moxibustion. After 6 weeks’ treatment, 22 cases were cured, with the shortest cure duration being 12 days and the longest being 27 days; 6...In the present paper, 32 cases of cutaneous defect were treated by using warm moxibustion. After 6 weeks’ treatment, 22 cases were cured, with the shortest cure duration being 12 days and the longest being 27 days; 6 cases were markedly effective and 4 cases were effective. Of the 28 cases in the control group who were treated with routine medicated dressing, 6 were cured, 13 had marked improvement and 9 had improvement, with the shortest cure duration being 18 days and the longest being 36 days. Statistical analysis shows a significant difference between the two groups in the effective rate, indicating that moxibustion therapy is of an advantage in the duration of treatment and therapeutic effect.展开更多
Objective To report evaluat of division region of abdominal wall large defect after tumors resection and repair methods by tissue flaps with pedicle. Methods Form October 1992 to September 2001, 8 cases large abdomina...Objective To report evaluat of division region of abdominal wall large defect after tumors resection and repair methods by tissue flaps with pedicle. Methods Form October 1992 to September 2001, 8 cases large abdominal wall defect after malignant tumors resection(10 × 10 cm-32 cm×32 cm) were reviewed. The defectcontributed:Ⅰ region, 2 cases; twin-Ⅱ region, 2; Ⅲ region, 2; Ⅰ and Ⅱ region of one side, 1 and total abdominal wall,one case, The tissue flaps of transposition included: gracilis myocutaneous flaps, 4; retus abdominal myocutaneous flaps, 2; external abdominal obligue musculo-fascia flaps, 2; latissimus dorsi muscle, tensor fasciae latae muscle and retus femoris muscle flaps each, 1. One patient used MycroMesh also. Results In the course of peroperation, the incisions of 8 cases healed in first time; total tissue flaps survived and all pateints started exercise left the bed in 3 weeks. All 8 patients were followed up average of 2 years and 5 months: the success rate of reconstruction展开更多
Objective To investigate the clinical characteristics and therapeutic of head trauma patients with skull defect. Methods A retrospective study of clinical data of 47 brain injury patients with skull defect in our hosp...Objective To investigate the clinical characteristics and therapeutic of head trauma patients with skull defect. Methods A retrospective study of clinical data of 47 brain injury patients with skull defect in our hospital from Janary 1993 to Janary 2009 was performed. Results Compared with展开更多
Al2O3/SiO2 multilayer high-reflective（HR） mirrors at 355 nm were prepared by electron beam evaporation, and post-irradiated with Ar/O mixture plasma. The surface defect density, reflective spectra, and laser-induced...Al2O3/SiO2 multilayer high-reflective（HR） mirrors at 355 nm were prepared by electron beam evaporation, and post-irradiated with Ar/O mixture plasma. The surface defect density, reflective spectra, and laser-induced damage characteristics were measured using optical microscopy, spectrophotometry, a damage testing system, and scanning electron microscopy（SEM）, respectively. The results indicated that moderate-time of irradiation enhanced the laser-induced damage threshold（LIDT） of the mirror, but prolonged irradiation produced surface defects, resulting in LIDT degradation. LIDT of the mirrors initially increased and subsequently decreased with the plasma processing time. SEM damage morphologies of the mirrors revealed that nanoscale absorbing defects in sub-layers was one of the key factors limiting the improvement of LIDT in 355 nm HR mirror.展开更多
The effect of solution heat treatment （SHT） on mechanical properties, microstructure and surface quality of Al-1.2Mg-0.6Si-0.2Cu-0.6Zn alloy was investigated by tensile test, Erichsen test, surface topography, scann...The effect of solution heat treatment （SHT） on mechanical properties, microstructure and surface quality of Al-1.2Mg-0.6Si-0.2Cu-0.6Zn alloy was investigated by tensile test, Erichsen test, surface topography, scanning electron microscope （SEM） and electron back-scattered diffraction （EBSD）. The results indicate that with the increase in SHT temperature, yield strength and cupping test value （IE） of the sheets increase greatly and reach a peak value, then decrease. Meanwhile, intermetallic com- pounds dissolve into matrix gradually. The grains grow up as SHT temperature increases, and abnormal grain growth leads to the surface defects after solution-treated above 560 ~C. Considering mechanical properties, IE value, residual phases, grain size and surface quality of the sheets, SHT temperature for the alloy should not be higher than 550 ℃.展开更多
The causes to the outer surface folding defects in N80-Q oil country tubular goods （OCTG） were investigated through the observation of the defects＇ morphology, microstructure and the analysis of the chemical compos...The causes to the outer surface folding defects in N80-Q oil country tubular goods （OCTG） were investigated through the observation of the defects＇ morphology, microstructure and the analysis of the chemical compositions. It is believed that the defect was resulted from the intrinsic flaws that originally existed on the billet; they were extended and oxidized during the following reheating and rolling processes. With more strict quality control and inspection of the billet, the defect can be prevented effectively from occurring.展开更多
〈110〉 oriented rods of TbDyFe giant magnetostrictive alloys have been prepared with the help of the zone melting directional solidification technique with a high temperature gradient. To acquire optimal magnetostric...〈110〉 oriented rods of TbDyFe giant magnetostrictive alloys have been prepared with the help of the zone melting directional solidification technique with a high temperature gradient. To acquire optimal magnetostrictive properties at low magnetic field, the TbDyFe alloys have been heat-treated at different temperatures and cooled at different rates. The relationships between the proc- ess of the heat treatment, microstructure, defects, and magnetostrictive properties of the TbDyFe materials have been studied. 2008 University of Science and Technology Beijing. All rights reserved.展开更多
Ameloblastoma is the most frequent odontogenic tumor of the jaw. If not treated, ameloblastoma can gain an enormous size and cause severe facial disfigurement and functional impairment. Here we report two patients aff...Ameloblastoma is the most frequent odontogenic tumor of the jaw. If not treated, ameloblastoma can gain an enormous size and cause severe facial disfigurement and functional impairment. Here we report two patients afflicted with extensive mandibular ameloblastoma (sized in 23 cm × 18 cm × 17 cm and 15 cm × 12 cm × 10 cm, respectively). Both the patients received the same sequential treatment including radical tumor resection, simultaneous reconstruction with fibula free flap graft, vertical distraction osteogenesis on the fibula graft, placement of endosseous dental implants, and final pros-thodontic rehabilitation. It took about 15 months to finish the entire course of treatment. And after the four-year follow-up, neither soft tissue related, nor hard tissue related problems were observed. Satisfactory facial symmetry, chewing and speech functions of the patients were restored. So this sequential treatment for extensive mandibular ameloblastoma can obtain an excellent effect by the shortest time and the lowest economical cost. Furthermore, the series also can be used to reconstruct giant mandibular defects caused by different reasons.展开更多
Objectives We did a retrospective study to summarize the surgical experience of anomalous pulmonary venous drainage (APVD) correction and discuss effective way of improving the surgical outcome. Methods From January 1...Objectives We did a retrospective study to summarize the surgical experience of anomalous pulmonary venous drainage (APVD) correction and discuss effective way of improving the surgical outcome. Methods From January 1985 to May 2008, 127 patients [56 men and 71 women, aged 14-55 years with an average of (26.79±10.62) years] with APVD underwent surgical treatments. Among them, 13 patients had simple partial APVD with intact atrial septum, 104 patients had partial APVD with atrial septal defect and 10 patients had total APVD. Seventy-one patients of them accompanied with other cardiac anomalies which were also corrected in their operations. Results One early operative death due to severe low cardiac output syndrome (LCOS) developed postoperatively, which resulted in a mortality rate of 0.78%. Among other patients, 10 patients complicated with LCOS, 11 patients with arrhythmia, 7 patients with acute renal failure and 4 patients with poor wound healing, all discharged from hospital after treatment. Postoperative echocardiography reexamination revealed 1 case of mild residual shunt in atrial septum but without pulmonary vein stenosis. Conclusion For right atrial and ventricle enlarged patients with or without pulmonary hypertension, surgeons should be vigilance of accompanied APVD whether atrial septal defects exist or not. As long as no contraindications are found, surgical treatment should be performed once accurate diagnosis is obtained.展开更多
基金the grant from the Ministry of Science and Technology of the People’s Republic of China(grant number 2016YFB1101501)Beijing Municipal Science&Technology Commission(Project Z181100001718195)。
文摘Bone defect repairs are based on bone graft fusion or replacement.Current large bone defect treatments are inadequate and lack of reliable technology.Therefore,we aimed to investigate a simple technique using three-dimensional(3D)-printed individualized porous implants without any bone grafts,osteoinductive agents,or surface biofunctionalization to treat large bone defects,and systematically study its long-term therapeutic effects and osseointegration characteristics.Twenty-six patients with large bone defects caused by tumor,infection,or trauma received treatment with individualized porous implants;among them,three typical cases underwent a detailed study.Additionally,a large segmental femur defect sheep model was used to study the osseointegration characteristics.Immediate and long-term biomechanical stability was achieved,and the animal study revealed that the bone grew into the pores with gradual remodeling,resulting in a long-term mechanically stable implant-bone complex.Advantages of 3D-printed microporous implants for the repair of bone defects included 1)that the stabilization devices were immediately designed and constructed to achieve early postoperative mobility,and 2)that osseointegration between the host bone and implants was achieved without bone grafting.Our osseointegration method,in which the“implant-bone”interface fusion concept was used instead of“bone-bone”fusion,subverts the traditional idea of osseointegration.
文摘Newly built tunnels often encounter a series of defects within the first few years of operation.If not promptly addressed and reinforced,these defects threaten the tunnel's durability and stability and bring severe challenges to its safe operation.This study aims to explore reinforcement techniques for addressing defects in newly built tunnels.The research begins with an analysis of common defects found in newly built tunnels,followed by a case study of the Jinfeng Tunnel in Chongqing,examining the post-construction defects.The actual reinforcement strategies and methods employed for the tunnel are then discussed.Finally,based on the research findings,this study provides insights and references for tunnel operation and construction units in China,aiming to enhance the overall quality of tunnel engineering in the country,align with sustainable development goals,and promote further improvements at a macro level.
文摘Jinping I hydropower station is one of the most challenging projects in China due to its highest arch dam and complex geological conditions for construction.After geological investigation into the dam foundation,a few large-scale weak discontinuities are observed.The rock masses in the left dam foundation are intensively unloaded,approximately to the depth of 150–300 m.These serious geological defects lead to a geological asymmetry on the left and right banks,and thus some major diffculties of dam construction are encountered.In this paper,the influences of geological defects on the project are analyzed,followed by the concepts and methods of treatment design.Based on the analysis,the treatment methods of the weak rock masses and discontinuities are carefully determined,including the concrete cushion,concrete replacement grids,and consolidation grouting.They work together to enhance the strength and integrity of the dam foundation.Evaluations and calibrations through geo-mechanical model tests in combination with feld monitoring results in early impoundment period show that the arch dam and its foundation are roughly stable,suggesting that the treatment designs are reasonable and effective.The proposed treatment methods and concepts in the context can be helpful for similar complex rock projects.
基金supported by the National Natural Science Foundation of China(21073023 and 20906008)the Fundamental Research Funds for the Central Universities(DUT12YQ03)the CSC and DAAD for a Project Based Personnel Exchange Program
文摘A direct strategy for the creation of defects on carbon nanofibers (CNFs) has been developed by steam treatment.Nitrogen physisorption,XRD,Raman spectra,SEM and TEM analyses proved the existence of the new defects on CNFs.BET surface area of CNFs after steam treatment was enhanced from 20 to 378 m2/g.Pd catalysts supported on CNFs were also prepared by colloidal deposition method.The different activity of Pd/CNFs catalysts in the partial hydrogenation of phenylacetylene further demonstrated the diverse surfaces of CNFs could be formed by steam treatment.
文摘In the present paper, 32 cases of cutaneous defect were treated by using warm moxibustion. After 6 weeks’ treatment, 22 cases were cured, with the shortest cure duration being 12 days and the longest being 27 days; 6 cases were markedly effective and 4 cases were effective. Of the 28 cases in the control group who were treated with routine medicated dressing, 6 were cured, 13 had marked improvement and 9 had improvement, with the shortest cure duration being 18 days and the longest being 36 days. Statistical analysis shows a significant difference between the two groups in the effective rate, indicating that moxibustion therapy is of an advantage in the duration of treatment and therapeutic effect.
文摘Objective To report evaluat of division region of abdominal wall large defect after tumors resection and repair methods by tissue flaps with pedicle. Methods Form October 1992 to September 2001, 8 cases large abdominal wall defect after malignant tumors resection(10 × 10 cm-32 cm×32 cm) were reviewed. The defectcontributed:Ⅰ region, 2 cases; twin-Ⅱ region, 2; Ⅲ region, 2; Ⅰ and Ⅱ region of one side, 1 and total abdominal wall,one case, The tissue flaps of transposition included: gracilis myocutaneous flaps, 4; retus abdominal myocutaneous flaps, 2; external abdominal obligue musculo-fascia flaps, 2; latissimus dorsi muscle, tensor fasciae latae muscle and retus femoris muscle flaps each, 1. One patient used MycroMesh also. Results In the course of peroperation, the incisions of 8 cases healed in first time; total tissue flaps survived and all pateints started exercise left the bed in 3 weeks. All 8 patients were followed up average of 2 years and 5 months: the success rate of reconstruction
文摘Objective To investigate the clinical characteristics and therapeutic of head trauma patients with skull defect. Methods A retrospective study of clinical data of 47 brain injury patients with skull defect in our hospital from Janary 1993 to Janary 2009 was performed. Results Compared with
基金Funded by the National Natural Science Foundation of China(No.11174208)the NSAF(No.U1430121)the Shenzhen Basic Research Project(Nos.JCYJ20150529164656098,ZDSY20170228105421966)
文摘Al2O3/SiO2 multilayer high-reflective（HR） mirrors at 355 nm were prepared by electron beam evaporation, and post-irradiated with Ar/O mixture plasma. The surface defect density, reflective spectra, and laser-induced damage characteristics were measured using optical microscopy, spectrophotometry, a damage testing system, and scanning electron microscopy（SEM）, respectively. The results indicated that moderate-time of irradiation enhanced the laser-induced damage threshold（LIDT） of the mirror, but prolonged irradiation produced surface defects, resulting in LIDT degradation. LIDT of the mirrors initially increased and subsequently decreased with the plasma processing time. SEM damage morphologies of the mirrors revealed that nanoscale absorbing defects in sub-layers was one of the key factors limiting the improvement of LIDT in 355 nm HR mirror.
基金supported by the National Program on Key Basic Research Project of China(No. 2012CB619504)the National Natural Science Foundation of China(No.51271037)
文摘The effect of solution heat treatment （SHT） on mechanical properties, microstructure and surface quality of Al-1.2Mg-0.6Si-0.2Cu-0.6Zn alloy was investigated by tensile test, Erichsen test, surface topography, scanning electron microscope （SEM） and electron back-scattered diffraction （EBSD）. The results indicate that with the increase in SHT temperature, yield strength and cupping test value （IE） of the sheets increase greatly and reach a peak value, then decrease. Meanwhile, intermetallic com- pounds dissolve into matrix gradually. The grains grow up as SHT temperature increases, and abnormal grain growth leads to the surface defects after solution-treated above 560 ~C. Considering mechanical properties, IE value, residual phases, grain size and surface quality of the sheets, SHT temperature for the alloy should not be higher than 550 ℃.
文摘The causes to the outer surface folding defects in N80-Q oil country tubular goods （OCTG） were investigated through the observation of the defects＇ morphology, microstructure and the analysis of the chemical compositions. It is believed that the defect was resulted from the intrinsic flaws that originally existed on the billet; they were extended and oxidized during the following reheating and rolling processes. With more strict quality control and inspection of the billet, the defect can be prevented effectively from occurring.
文摘〈110〉 oriented rods of TbDyFe giant magnetostrictive alloys have been prepared with the help of the zone melting directional solidification technique with a high temperature gradient. To acquire optimal magnetostrictive properties at low magnetic field, the TbDyFe alloys have been heat-treated at different temperatures and cooled at different rates. The relationships between the proc- ess of the heat treatment, microstructure, defects, and magnetostrictive properties of the TbDyFe materials have been studied. 2008 University of Science and Technology Beijing. All rights reserved.
文摘Ameloblastoma is the most frequent odontogenic tumor of the jaw. If not treated, ameloblastoma can gain an enormous size and cause severe facial disfigurement and functional impairment. Here we report two patients afflicted with extensive mandibular ameloblastoma (sized in 23 cm × 18 cm × 17 cm and 15 cm × 12 cm × 10 cm, respectively). Both the patients received the same sequential treatment including radical tumor resection, simultaneous reconstruction with fibula free flap graft, vertical distraction osteogenesis on the fibula graft, placement of endosseous dental implants, and final pros-thodontic rehabilitation. It took about 15 months to finish the entire course of treatment. And after the four-year follow-up, neither soft tissue related, nor hard tissue related problems were observed. Satisfactory facial symmetry, chewing and speech functions of the patients were restored. So this sequential treatment for extensive mandibular ameloblastoma can obtain an excellent effect by the shortest time and the lowest economical cost. Furthermore, the series also can be used to reconstruct giant mandibular defects caused by different reasons.
基金supported by Natural Science Foundation of Guangdong Province ( No.5001161)Medical Science Foundation of Guangdong Province (No.A2005049)
文摘Objectives We did a retrospective study to summarize the surgical experience of anomalous pulmonary venous drainage (APVD) correction and discuss effective way of improving the surgical outcome. Methods From January 1985 to May 2008, 127 patients [56 men and 71 women, aged 14-55 years with an average of (26.79±10.62) years] with APVD underwent surgical treatments. Among them, 13 patients had simple partial APVD with intact atrial septum, 104 patients had partial APVD with atrial septal defect and 10 patients had total APVD. Seventy-one patients of them accompanied with other cardiac anomalies which were also corrected in their operations. Results One early operative death due to severe low cardiac output syndrome (LCOS) developed postoperatively, which resulted in a mortality rate of 0.78%. Among other patients, 10 patients complicated with LCOS, 11 patients with arrhythmia, 7 patients with acute renal failure and 4 patients with poor wound healing, all discharged from hospital after treatment. Postoperative echocardiography reexamination revealed 1 case of mild residual shunt in atrial septum but without pulmonary vein stenosis. Conclusion For right atrial and ventricle enlarged patients with or without pulmonary hypertension, surgeons should be vigilance of accompanied APVD whether atrial septal defects exist or not. As long as no contraindications are found, surgical treatment should be performed once accurate diagnosis is obtained.
