This study aimed to introduce a modified Byars staged procedure and investigate its application value in patients with severe hypospadias.We retrospectively analyzed the clinical data of patients with severe hypospadi...This study aimed to introduce a modified Byars staged procedure and investigate its application value in patients with severe hypospadias.We retrospectively analyzed the clinical data of patients with severe hypospadias admitted to the First Affiliated Hospital of Sun Yat-sen University(Guangzhou,China)between October 2012 and October 2022.In total,31 patients underwent the conventional Byars procedure(conventional group),and 45 patients underwent the modified Byars staged procedure(modified group).Our modified strategy was built upon the standard Byars procedure by incorporating glansplasty during the first stage and employing a Y-shaped flap in conjunction with a glandular tunnel for urethroplasty during the second stage.Notably,there were no statistically significant differences in the preoperative baseline characteristics,duration of surgery,amount of blood loss,or occurrence of postoperative complications,including urethral fistula,stricture and diverticulum,or penile curvature,between the conventional and modified groups.However,there was a significantly lower incidence of coronal sulcus fistula(0 vs 16.1%,P=0.02)and glans dehiscence(0 vs 12.9%,P=0.02)in the surgical group than that in the conventional group.In addition,the modified group exhibited a notably greater rate of normotopic urethral opening(100.0%vs 83.9%,P=0.01)and a higher mean score on the Hypospadias Objective Penile Evaluation(HOPE;mean±standard error of mean:8.6±0.2 vs 7.9±0.3,P=0.02)than did the conventional group.In conclusion,the modified Byars staged procedure significantly reduced the risks of glans dehiscence and coronal sulcus fistula.Consequently,it offers a promising approach for achieving favorable penile esthetics,thereby providing a reliable therapeutic option for severe hypospadias.展开更多
The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur batteries.Herein,we propose a dual-action strategy to address the lithiu...The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur batteries.Herein,we propose a dual-action strategy to address the lithium dendrite issue in stages by constructing a multifunctional surface-negatively-charged nanodiamond layer with high ductility and robust puncture resistance on polypropylene (PP) separator.The uniformly loaded compact negative layer can not only significantly enhance electron transmission efficiency and promote uniform lithium deposition,but also reduce the formation of dendrite during early deposition stage.Most importantly,under the strong puncture stress encountered during the deterioration of lithium dendrite growth under limiting current,the high ductility and robust puncture resistance(145.88 MPa) of as-obtained nanodiamond layer can effectively prevent short circuits caused by unavoidable lithium dendrite.The Li||Li symmetrical cells assembled with nanodiamond layer modified PP demonstrated a stable cycle of over 1000 h at 2 mA cm^(-2)with a polarization voltage of only 29.3 mV.Additionally,the negative charged layer serves as a physical barrier blocking lithium polysulfide ions,effectively mitigating capacity attenuation.The improved cells achieved a capacity decay of only 0.042%per cycle after 700 cycles at 3 C,demonstrating effective suppression of dendrite growth and capacity attenuation,showing promising prospect.展开更多
The Yemaomian landslide,the largest near-dam accumulation landslide in the Three Gorges Reservoir area,is situated 17 km upstream of the Three Gorges Dam.Nearly 20 years of monitoring data indicate that the landslide ...The Yemaomian landslide,the largest near-dam accumulation landslide in the Three Gorges Reservoir area,is situated 17 km upstream of the Three Gorges Dam.Nearly 20 years of monitoring data indicate that the landslide has been undergoing slow deformation with a low deformation rate and magnitude.This paper applies a stepwise linear regression method and a mechanical model of hydrodynamics triggering to deeply explore the relationship between geological conditions,external factors,and deformation characteristics.Based on the stage transition characteristics of external triggering factors,the deformation evolution process of the landslide since the reservoir impoundment is divided into three stages:(1)June 2003-September 2006,the landslide was reactivated by the significant rise in reservoir water levels,in a retrogressive mode;(2)October 2006-September 2018,the deformation mode shifted from retrogressive mode to creep deformation as a whole,primarily due to the degradation effect on the landslide mass caused by immersion in reservoir water.(3)October 2018-February 2024,a further significant reduction in the overall deformation rate and the impact of seasonal rainfall on landslide deformation surpassed that of reservoir water level fluctuations.The main component of landslide deformation is convergent creep,and extreme rainfall will be an important triggering factor for the local instability.Identifying the deformation evolution stages and determining the dominant external influencing factors at each stage is crucial for landslide research,and this paper provides an effective research paradigm for this purpose.展开更多
BACKGROUND Associating liver partition and portal vein ligation for staged hepatectomy(ALPPS)is a procedure used for patients with initially unresectable colorectal liver metastases(CRLM).However,the procedure has bee...BACKGROUND Associating liver partition and portal vein ligation for staged hepatectomy(ALPPS)is a procedure used for patients with initially unresectable colorectal liver metastases(CRLM).However,the procedure has been reported to be associated with high morbidity and mortality.Laparoscopic ALPPS has recently been reported as a minimally invasive technique that reduces perioperative risks.AIM To assess the safety and feasibility of full laparoscopic ALPPS in patients with CRLM.METHODS A retrospective analysis was conducted on all consecutive patients with CRLM who underwent full laparoscopic ALPPS at the Sixth Affiliated Hospital of Sun Yat-sen University between March 2021 and July 2024.RESULTS Fifteen patients were included,13 with synchronous liver metastases.Nine patients had more than five liver tumors,with the highest count being 22.The median diameter of the largest lesion was 2.8 cm on preoperative imaging.No extrahepatic metastases were observed.RAS mutations were detected in nine patients,and 14 underwent preoperative chemotherapy.The median increase in future liver remnant volume during the interstage interval was 47.0%.All patients underwent R0 resection.Overall complication rates were 13.3%(stage 1)and 53.3%(stage 2),while major complication rates(Clavien-Dindo≥IIIa)were 13.3%(stage 1)and 33.3%(stage 2).No mortality occurred in either stage.The median hospital stay after stage 2 was 10 days.CONCLUSION Full laparoscopic ALPPS for CRLM is safe and feasible,with the potential for reduced morbidity and mortality,offering radical resection opportunities for patients with initially unresectable CRLM.展开更多
Experimental investigations on NOx emissions of a single-cup,Lean Premixed Prevaporized(LPP),module combustor were carried out at elevated inlet temperature and pressure up to810 K and 2.0 MPa,close to the real operat...Experimental investigations on NOx emissions of a single-cup,Lean Premixed Prevaporized(LPP),module combustor were carried out at elevated inlet temperature and pressure up to810 K and 2.0 MPa,close to the real operating conditions of aero-engine combustors.This LPP combustor adopts centrally staged fuel injections which could produce separated stratified swirling spray flame.In the NOx emissions measurements,the ranges of dome equivalence ratio and fuel stage ratio were from 0.55 to 0.58 and 8%to 24%,respectively.The optical diagnosis on separated stratified swirling spray flame were carried out with fuel stage ratio changing from 15%to 30%.Therefore,NO*and OH*chemiluminescence images were obtained.The results show that NOx emissions increase with the increase of the fuel stage ratio.And from the chemiluminescence images,the main flame and pilot flame are found weakly coupled.The pilot flame plays a significant role in NOx emission production because of its higher adiabatic flame temperature.Based on the results of chemiluminescence optical tests,a new NOx emission prediction model is proposed based on the Lefebvre’s single flame model The estimate of local equivalence ratio of the pilot stage’s nonpremixed flame is modified considering the characteristics of spray combustion,and a"PLUS"emission prediction model suitable for separated stratified swirling spray flame is obtained.Compared to the experimental data,the"PLUS"model exhibits a good prediction in a range of±13%of deviation.展开更多
Since its introduction in 2012,associating liver partition with portal vein ligation for staged hepatectomy(ALPPS)has significantly expanded the pool of candidates for liver resection.It offers patients with insuffici...Since its introduction in 2012,associating liver partition with portal vein ligation for staged hepatectomy(ALPPS)has significantly expanded the pool of candidates for liver resection.It offers patients with insufficient liver function a chance of a cure.ALPPS is most controversial when its high morbidity and mortality is concerned.Operative mortality is usually a result of posthepatectomy liver failure and can be minimized with careful patient selection.Elderly patients have limited reserve for tolerating the demanding operation.Patients with colorectal liver metastasis have normal liver and are ideal candidates.ALPPS for cholangiocarcinoma is technically challenging and associated with fair outcomes.Patients with hepatocellular carcinoma have chronic liver disease and limited parenchymal hypertrophy.However,in selected patients with limited hepatic fibrosis satisfactory outcomes have been produced.During the inter-stage period,serum bilirubin and creatinine level and presence of surgical complication predict mortality after stage II.Kinetic growth rate and hepatobiliary scintigraphy also guide the decision whether to postpone or omit stage II surgery.The outcomes of ALPPS have been improved by a combination of technical modifications.In patients with challenging anatomy,partial ALPPS potentially reduces morbidity,but remnant hypertrophy may compare unfavorably to a complete split.When compared to conventional two-stage hepatectomy with portal vein embolization or portal vein ligation,ALPPS offers a higher resection rate for colorectal liver metastasis without increased morbidity or mortality.While ALPPS has obvious theoretical oncological advantages over two-stage hepatectomy,the long-term outcomes are yet to be determined.展开更多
The three-dimensional （3D） reacting flow in a staged supersonic combustor is examined numerically. In order to obtain the optimum stream-wise vortices, a swept ramp injector is chosen as the second-stage wall inject...The three-dimensional （3D） reacting flow in a staged supersonic combustor is examined numerically. In order to obtain the optimum stream-wise vortices, a swept ramp injector is chosen as the second-stage wall injection combined with the first-stage central strut injection. The performance of the two-staged injection is compared with that of a one-staged injection, while the strut is kept installed in both cases. The two-staged injections can make full use of the residual oxygen near the wall and release more heat. The second-stage injection further downstream avoids the strong shock waves in the isolator and results in a rising wall pressure and good burning effects after the wall injection. Therefore, it allows more fuel to be injected into the supersonic combustor without causing thermal choking. Parallel injection from the second-stage swept ramp shows low total pressure loss and the best burning efficiency, compared with the other injection angles.展开更多
AIM To report a single-center experience in rescue associating liver partition and portal vein ligation for staged hepatectomy(ALPPS), after failure of previous portal embolization. We also performed a literature revi...AIM To report a single-center experience in rescue associating liver partition and portal vein ligation for staged hepatectomy(ALPPS), after failure of previous portal embolization. We also performed a literature review.METHODS Between January 2014 and December 2015, every patient who underwent a rescue ALPPS procedure in Toulouse Rangueil University Hospital, France, was included. Every patient included had a project of major hepatectomy and a previous portal vein embolization(PVE) with insufficient future liver remnant to body weight ratio after the procedure. The ALPPS procedure was performed in two steps(ALPPS-1 and ALPPS-2), separated by an interval phase. ALPPS-2 was done within 7 to 9 d after ALPPS-1. To estimate the FLR, a computed tomography scan examination was performed 3 to 6 wk after the PVE procedure and 6 to 8 d after ALPPS-1. A transcystic stent was placed during ALPPS-1 and remained opened duringthe interval phase, in order to avoid biliary complications. Postoperative liver failure was defined using the 50-50 criteria. Postoperative complications were assessed according to the Dindo-Clavien Classification.RESULTS From January 2014 to December 2015, 7 patients underwent a rescue ALPPS procedure. Median FLR before PVE, ALPPS-1 and ALPPS-2 were respectively 263 cc(221-380), 450 cc(372-506), and 660 cc(575-776). Median FLR/BWR before PVE, ALPPS-1 and ALPPS-2 were respectively 0.4%(0.3-0.5), 0.6%(0.5-0.8), and 1%(0.8-1.2). Median volume growth of FLR was 69%(18-92) after PVE, and 45%(36-82) after ALPPS-1. The combination of PVE and ALPPS induced a growth of median initial FLR of +408 cc(254-513), leading to an increase of +149%(68-199). After ALPPS-2, 4 patients had stage Ⅰ-Ⅱ complications. Three patients had more severe complications(one stage Ⅲ, one stage Ⅳ and one death due to bowel perforation). Two patients suffered from postoperative liver failure according to the 50/50 criteria. None of our patients developed any biliary complication during the ALPPS procedure.CONCLUSION Rescue ALPPS may be an alternative after unsuccessful PVE and could allow previously unresectable patients to reach surgery. Biliary drainage seems to reduce biliary complications.展开更多
基金supported by funding from the Medical Research Funding of Guangdong(No.A2022499 to QGX)the National Natural Science Foundation of China(No.82301796 to PL)the Guangdong Province Regional Joint Fund-Youth Fund Project of China(No.2022A1515111201 to PL).
文摘This study aimed to introduce a modified Byars staged procedure and investigate its application value in patients with severe hypospadias.We retrospectively analyzed the clinical data of patients with severe hypospadias admitted to the First Affiliated Hospital of Sun Yat-sen University(Guangzhou,China)between October 2012 and October 2022.In total,31 patients underwent the conventional Byars procedure(conventional group),and 45 patients underwent the modified Byars staged procedure(modified group).Our modified strategy was built upon the standard Byars procedure by incorporating glansplasty during the first stage and employing a Y-shaped flap in conjunction with a glandular tunnel for urethroplasty during the second stage.Notably,there were no statistically significant differences in the preoperative baseline characteristics,duration of surgery,amount of blood loss,or occurrence of postoperative complications,including urethral fistula,stricture and diverticulum,or penile curvature,between the conventional and modified groups.However,there was a significantly lower incidence of coronal sulcus fistula(0 vs 16.1%,P=0.02)and glans dehiscence(0 vs 12.9%,P=0.02)in the surgical group than that in the conventional group.In addition,the modified group exhibited a notably greater rate of normotopic urethral opening(100.0%vs 83.9%,P=0.01)and a higher mean score on the Hypospadias Objective Penile Evaluation(HOPE;mean±standard error of mean:8.6±0.2 vs 7.9±0.3,P=0.02)than did the conventional group.In conclusion,the modified Byars staged procedure significantly reduced the risks of glans dehiscence and coronal sulcus fistula.Consequently,it offers a promising approach for achieving favorable penile esthetics,thereby providing a reliable therapeutic option for severe hypospadias.
基金National Natural Science Foundation of China (Grant 52372083, 52173255)Opening Project of the Jiangsu Key Laboratory for Chemistry of Low-Dimensional Materials (JSKC24025)+1 种基金Special Funds for the Trans-formation of Scientific and Technological Achievements in Jiangsu Province(BA2023003)Collaborative Innovation Center for Advanced Micro/nanomaterials and Equipment (Co-constructed by Jiangsu Province and Ministry of Education)。
文摘The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur batteries.Herein,we propose a dual-action strategy to address the lithium dendrite issue in stages by constructing a multifunctional surface-negatively-charged nanodiamond layer with high ductility and robust puncture resistance on polypropylene (PP) separator.The uniformly loaded compact negative layer can not only significantly enhance electron transmission efficiency and promote uniform lithium deposition,but also reduce the formation of dendrite during early deposition stage.Most importantly,under the strong puncture stress encountered during the deterioration of lithium dendrite growth under limiting current,the high ductility and robust puncture resistance(145.88 MPa) of as-obtained nanodiamond layer can effectively prevent short circuits caused by unavoidable lithium dendrite.The Li||Li symmetrical cells assembled with nanodiamond layer modified PP demonstrated a stable cycle of over 1000 h at 2 mA cm^(-2)with a polarization voltage of only 29.3 mV.Additionally,the negative charged layer serves as a physical barrier blocking lithium polysulfide ions,effectively mitigating capacity attenuation.The improved cells achieved a capacity decay of only 0.042%per cycle after 700 cycles at 3 C,demonstrating effective suppression of dendrite growth and capacity attenuation,showing promising prospect.
基金supported by the National Natural Science Foundation of China(Nos.U2340226,12072047,42277186)China Three Gorges Corporation under the contract of No.0799291(SXSN/5115)the Fundamental Research Funds for Central Public Welfare Research Institutes(CKSF20241014/YT,CKSF20241016/YT).
文摘The Yemaomian landslide,the largest near-dam accumulation landslide in the Three Gorges Reservoir area,is situated 17 km upstream of the Three Gorges Dam.Nearly 20 years of monitoring data indicate that the landslide has been undergoing slow deformation with a low deformation rate and magnitude.This paper applies a stepwise linear regression method and a mechanical model of hydrodynamics triggering to deeply explore the relationship between geological conditions,external factors,and deformation characteristics.Based on the stage transition characteristics of external triggering factors,the deformation evolution process of the landslide since the reservoir impoundment is divided into three stages:(1)June 2003-September 2006,the landslide was reactivated by the significant rise in reservoir water levels,in a retrogressive mode;(2)October 2006-September 2018,the deformation mode shifted from retrogressive mode to creep deformation as a whole,primarily due to the degradation effect on the landslide mass caused by immersion in reservoir water.(3)October 2018-February 2024,a further significant reduction in the overall deformation rate and the impact of seasonal rainfall on landslide deformation surpassed that of reservoir water level fluctuations.The main component of landslide deformation is convergent creep,and extreme rainfall will be an important triggering factor for the local instability.Identifying the deformation evolution stages and determining the dominant external influencing factors at each stage is crucial for landslide research,and this paper provides an effective research paradigm for this purpose.
基金Supported by Natural Science Foundation of Guangdong Province of China,No.2024A1515012862.
文摘BACKGROUND Associating liver partition and portal vein ligation for staged hepatectomy(ALPPS)is a procedure used for patients with initially unresectable colorectal liver metastases(CRLM).However,the procedure has been reported to be associated with high morbidity and mortality.Laparoscopic ALPPS has recently been reported as a minimally invasive technique that reduces perioperative risks.AIM To assess the safety and feasibility of full laparoscopic ALPPS in patients with CRLM.METHODS A retrospective analysis was conducted on all consecutive patients with CRLM who underwent full laparoscopic ALPPS at the Sixth Affiliated Hospital of Sun Yat-sen University between March 2021 and July 2024.RESULTS Fifteen patients were included,13 with synchronous liver metastases.Nine patients had more than five liver tumors,with the highest count being 22.The median diameter of the largest lesion was 2.8 cm on preoperative imaging.No extrahepatic metastases were observed.RAS mutations were detected in nine patients,and 14 underwent preoperative chemotherapy.The median increase in future liver remnant volume during the interstage interval was 47.0%.All patients underwent R0 resection.Overall complication rates were 13.3%(stage 1)and 53.3%(stage 2),while major complication rates(Clavien-Dindo≥IIIa)were 13.3%(stage 1)and 33.3%(stage 2).No mortality occurred in either stage.The median hospital stay after stage 2 was 10 days.CONCLUSION Full laparoscopic ALPPS for CRLM is safe and feasible,with the potential for reduced morbidity and mortality,offering radical resection opportunities for patients with initially unresectable CRLM.
基金supported by the National Natural Science Foundation of China(No.91641109).
文摘Experimental investigations on NOx emissions of a single-cup,Lean Premixed Prevaporized(LPP),module combustor were carried out at elevated inlet temperature and pressure up to810 K and 2.0 MPa,close to the real operating conditions of aero-engine combustors.This LPP combustor adopts centrally staged fuel injections which could produce separated stratified swirling spray flame.In the NOx emissions measurements,the ranges of dome equivalence ratio and fuel stage ratio were from 0.55 to 0.58 and 8%to 24%,respectively.The optical diagnosis on separated stratified swirling spray flame were carried out with fuel stage ratio changing from 15%to 30%.Therefore,NO*and OH*chemiluminescence images were obtained.The results show that NOx emissions increase with the increase of the fuel stage ratio.And from the chemiluminescence images,the main flame and pilot flame are found weakly coupled.The pilot flame plays a significant role in NOx emission production because of its higher adiabatic flame temperature.Based on the results of chemiluminescence optical tests,a new NOx emission prediction model is proposed based on the Lefebvre’s single flame model The estimate of local equivalence ratio of the pilot stage’s nonpremixed flame is modified considering the characteristics of spray combustion,and a"PLUS"emission prediction model suitable for separated stratified swirling spray flame is obtained.Compared to the experimental data,the"PLUS"model exhibits a good prediction in a range of±13%of deviation.
文摘Since its introduction in 2012,associating liver partition with portal vein ligation for staged hepatectomy(ALPPS)has significantly expanded the pool of candidates for liver resection.It offers patients with insufficient liver function a chance of a cure.ALPPS is most controversial when its high morbidity and mortality is concerned.Operative mortality is usually a result of posthepatectomy liver failure and can be minimized with careful patient selection.Elderly patients have limited reserve for tolerating the demanding operation.Patients with colorectal liver metastasis have normal liver and are ideal candidates.ALPPS for cholangiocarcinoma is technically challenging and associated with fair outcomes.Patients with hepatocellular carcinoma have chronic liver disease and limited parenchymal hypertrophy.However,in selected patients with limited hepatic fibrosis satisfactory outcomes have been produced.During the inter-stage period,serum bilirubin and creatinine level and presence of surgical complication predict mortality after stage II.Kinetic growth rate and hepatobiliary scintigraphy also guide the decision whether to postpone or omit stage II surgery.The outcomes of ALPPS have been improved by a combination of technical modifications.In patients with challenging anatomy,partial ALPPS potentially reduces morbidity,but remnant hypertrophy may compare unfavorably to a complete split.When compared to conventional two-stage hepatectomy with portal vein embolization or portal vein ligation,ALPPS offers a higher resection rate for colorectal liver metastasis without increased morbidity or mortality.While ALPPS has obvious theoretical oncological advantages over two-stage hepatectomy,the long-term outcomes are yet to be determined.
基金National Natural Science Foundation of China(50306011)the German Research Foundation (DFG) (GRK1095/1)
文摘The three-dimensional （3D） reacting flow in a staged supersonic combustor is examined numerically. In order to obtain the optimum stream-wise vortices, a swept ramp injector is chosen as the second-stage wall injection combined with the first-stage central strut injection. The performance of the two-staged injection is compared with that of a one-staged injection, while the strut is kept installed in both cases. The two-staged injections can make full use of the residual oxygen near the wall and release more heat. The second-stage injection further downstream avoids the strong shock waves in the isolator and results in a rising wall pressure and good burning effects after the wall injection. Therefore, it allows more fuel to be injected into the supersonic combustor without causing thermal choking. Parallel injection from the second-stage swept ramp shows low total pressure loss and the best burning efficiency, compared with the other injection angles.
文摘AIM To report a single-center experience in rescue associating liver partition and portal vein ligation for staged hepatectomy(ALPPS), after failure of previous portal embolization. We also performed a literature review.METHODS Between January 2014 and December 2015, every patient who underwent a rescue ALPPS procedure in Toulouse Rangueil University Hospital, France, was included. Every patient included had a project of major hepatectomy and a previous portal vein embolization(PVE) with insufficient future liver remnant to body weight ratio after the procedure. The ALPPS procedure was performed in two steps(ALPPS-1 and ALPPS-2), separated by an interval phase. ALPPS-2 was done within 7 to 9 d after ALPPS-1. To estimate the FLR, a computed tomography scan examination was performed 3 to 6 wk after the PVE procedure and 6 to 8 d after ALPPS-1. A transcystic stent was placed during ALPPS-1 and remained opened duringthe interval phase, in order to avoid biliary complications. Postoperative liver failure was defined using the 50-50 criteria. Postoperative complications were assessed according to the Dindo-Clavien Classification.RESULTS From January 2014 to December 2015, 7 patients underwent a rescue ALPPS procedure. Median FLR before PVE, ALPPS-1 and ALPPS-2 were respectively 263 cc(221-380), 450 cc(372-506), and 660 cc(575-776). Median FLR/BWR before PVE, ALPPS-1 and ALPPS-2 were respectively 0.4%(0.3-0.5), 0.6%(0.5-0.8), and 1%(0.8-1.2). Median volume growth of FLR was 69%(18-92) after PVE, and 45%(36-82) after ALPPS-1. The combination of PVE and ALPPS induced a growth of median initial FLR of +408 cc(254-513), leading to an increase of +149%(68-199). After ALPPS-2, 4 patients had stage Ⅰ-Ⅱ complications. Three patients had more severe complications(one stage Ⅲ, one stage Ⅳ and one death due to bowel perforation). Two patients suffered from postoperative liver failure according to the 50/50 criteria. None of our patients developed any biliary complication during the ALPPS procedure.CONCLUSION Rescue ALPPS may be an alternative after unsuccessful PVE and could allow previously unresectable patients to reach surgery. Biliary drainage seems to reduce biliary complications.
