Nonconjugated Polymers Enabled Solar Water Oxidation.

Wholly distinct from conjugated polymers which are featured by generic charge transfer capability stemming from a conjugated molecular structure, solid nonconjugated polymers mediated charge transport has long been deemed as theoretically impossible because of the deficiency of π electrons along the molecular skeleton, thereby retarding their widespread applications in solar energy conversion. Herein, we first conceptually unveil that intact encapsulation of metal oxides (e.g., TiO2, WO3, Fe2O3, and ZnO) with an ultrathin nonconjugated polyelectrolyte of branched polyethylenimine (BPEI) can unexpectedly accelerate the unidirectional charge transfer to the active sites and foster the defect generation, which contributes to the boosted charge separation and prolonged charge lifetime, ultimately resulting in considerably improved photoelectrochemical (PEC) water oxidation activities. The interfacial charge transport origins endowed by BPEI adornment are elucidated, which include acting as a hole-withdrawing mediator, promoting vacancy generation, and stimulating the directional charge flow route. We additionally ascertain that such charge transport characteristics of BPEI are universal. This work would unlock the charge transfer capability of nonconjugated polymers for solar water oxidation. The nonconjugated insulating polymer was utilized as a charge transport mediator for boosting charge migration and separation over metal oxides toward solar water oxidation.

Ileocecal valve-preservation ileocecostomy (IVPI) in infants with extremely short distal ileum after primary stoma.

PURPOSE: Preserving the ileocecal valve (ICV) has shown significant benefits. We present our experience with 18 infants who underwent ileocecal valve-preservation ileocecostomy (IVPI) with an extremely short distal ileum after primary ileostomy. METHODS: A retrospective analysis was conducted on IVPI cases between 2014 and 2020. Medical records were reviewed, including birth weight, age, primary diseases, length of ileus stump, surgical time and procedure, time to enteral feeding, postoperative hospital stay, and complications. RESULTS: Eighteen patients (male: female = 12:6, median birth weight 1305 (750-4000) g, median gestational age 29 + 5 (27 + 6-39 + 6) weeks) were included in the analysis. Causes of surgery included necrotizing enterocolitis (13), ileocecal intestinal atresia (1), ileum volvulus (2), meconium peritonitis (1), and secondary intestinal fistula (1). The median corrected age of ileostomy closure was 3.2 months (2.0-8.0 months). The distance from the distal ileal stoma to the ICV ranged from 0.5 to 2 cm. The median length of the residual bowel was 90 cm (50-130 cm). ICV-plasty was performed in 3 cases due to secondary ICV occlusion or stenosis. All patients resumed feeding within 6 to 11 days after surgery. The postoperative hospital stay ranged from 12 to 108 days (median: 16.5 days). Complications included incisional infections in 2 cases, anastomotic stricture and adhesive ileus in 1 case, nosocomial sepsis and septic shock in 1 case. All children showed normal growth and development during a 6-65 month follow-up. CONCLUSIONS: IVPI is safe and feasible for infants with an extremely short distal ileal stump. ICV-plasty could be applicable for cases with ileocecal occlusion/stenosis.

River ecological flow early warning forecasting using baseflow separation and machine learning in the Jiaojiang River Basin, Southeast China.

Ecological flow early warning is crucial for the rational management of watershed water resources. However, determining of accurate ecological flow threshold and choosing the appropriate forecasting model are challenging tasks. In this study, we initially developed a baseflow separation and Tennant method-based technique for calculating ecological river flow. Then an ecological flow early warning model was created using the machine learning technique based on distributed gradient enhancement framework (LightGBM). Finally, we utilized the framework of Shapley Additive Planning (SHAP) to explain how various hydrometeorological factors affect the variations in ecological flow conditions. The Jiaojiang River basin in southeast China is selected as the study area, and the hydrological stations in upstream of Baizhiao (BZA) and Shaduan (SD) are chosen for key analysis. The results of these applications show that the monthly baseflow frequency of the river ecological flow conditions of the two stations in the dry season is 20 % (7.49 m3/s) and 30 % (4.79 m3/s), respectively. The ecological flow level early warning forecasting accuracy is close to 90 % in the BZA and SD stations during dry and wet seasons. The variations of ecological flow are most affected by evaporation and base flow index. The results of this study can serve as a strong basis for the effective allocation and utilization of locally available water resources.

Transumbilical laparoendoscopic single-site pyeloplasty in infants and children: initial experience and short-term outcome.

BACKGROUND: Scar-free abdominal wall surgery is a research hotspot in recent years. This study presented surgical skills of transumbilical laparoendoscopic single-site pyeloplasty (LESS-P) for pediatric patients with ureteropelvic junction obstruction (UPJO) and its clinical application. METHODS: Twenty-four pediatric patients with UPJO had transumbilical LESS-P performed by the same surgeon from June to December 2010. Among them, 16 were males and 8 females aged from 2 to 62 months with average of 14 months. Eighteen patients had obstruction on the left ureteropelvic junction and six on the right. The renal pelvis and ureter were anastomosed using 5-0 absorbable sutures and a double-J ureteric stent was placed through the anastomotic stoma. RESULTS: All operations were successful. None was converted to open surgery and no additional sheath tube or incision besides umbilicus was needed. No intraoperative complications occurred. Ectopic blood vessels were found in two cases during surgery. The mean operative time was 145 min, and the average blood loss about 10 ml. Abdominal drainage tubes were remained for 2-9 days after surgery. The mean postoperative hospital time was 7 days. Two patients had postoperative urinary fistula, which naturally disappeared at 4 and 7 days of postoperation, respectively. Ultrasound and diuretic renal scintigraphy in follow-up found 23 patients had significantly decreased renal pelvis diameter. Although the other one showed no obvious change, but diuretic renography showed significantly improved excretion as indicated by increased glomerular filtration rate from 29 ml/min before surgery to 46 ml/min 6 months after surgery. CONCLUSION: Pediatric transumbilical LESS-P is not only safe and effective but also can well meet patient's aesthetic desire for scar-free abdominal wall.

Surgical resection of chemotherapy-insensitive pulmonary metastases in children with hepatoblastoma in China: A single-center experience.

Objective: The objective of this study is to investigate the operation timing, methods, and outcome of pulmonary metastases of hepatoblastoma (HB) in children. Methods: The clinical and follow-up data of 53 children with pulmonary metastases of HB that were admitted to our hospital from January 2012 to December 2018 were retrospectively analyzed. The pediatric patients, 36 male and 17 female, aged 13-124 months with the median age of 41 months, and all underwent routine thoracotomy. Results: In the 53 cases, 77 lung metastatic tumors were resected. Further, 37 patients received only one operation, 10 received two operations, 4 received 3 operations, and 2 received 4 operations. Based on Kaplan-Meier analysis, the accumulative overall survival (OS) rates at 1, 3, and 5 years were 86.8%, 69.0%, and 57.0%, respectively (median OS time: 60 months; 95% CI: 50.675-69.709 months), and accumulative EFS (vent-free survival) rates at 1, 3, and 5 years were 86.8%, 67.0%, and 55.4%, respectively (median EFS time: 59 months; 95% CI: 49.519-68.578 months). According to univariate analysis, OS was significantly altered for patients with no more than 5 nodules (p = 0.023), lung metastases without extrapulmonary metastases (p = 0.000), and laterality (p = 0.029). Gender and age (less than three years) were not significantly related to survival. According to univariate analysis, lung metastases with extrapulmonary metastases could be considered as individual factor contributing to poorer prognosis. Conclusion: In this pediatric group, patients with residual nodules after chemotherapy of HB could benefit from surgical treatment, but the appropriate surgical indication of metastasectomy needs to be further investigated.

Total extrapleura sternal elevation for the correction of pectus excavatum in children.

PURPOSE: The aim of this study was to evaluate the efficacy and safety of the thoracoscopic total extrapleural approach of the Nuss procedure for the correction of pectus excavatum in children. MATERIALS AND METHODS: Under thoracoscopic guidance, an extrapleural tunnel was created by using a blunt dissector via a right thoracic incision. A steel bar was inserted in the entirely extrapleural tunnel. The bar was turned and fixed as in the standard Nuss procedure. RESULTS: The operations were completed successfully in all patients. The operating time ranged from 35 to 50 minutes (median, 45). The intraoperative blood loss was 2 to 3 mL. There was no pneumothorax or hydrothoraxin our series. All patients were followed up for 2-6 months, and the surgical outcomes were excellent. CONCLUSIONS: The extrapleura Nuss procedure under thoracoscopic guidance is a safe and less traumatic procedure for the correction of pectus excavatum.

Transumbilical multi-port laparoscopic pyeloplasty versus transumbilical single-site laparoscopic pyeloplasty for ureteropelvic junction obstruction in children: A retrospectively comparative study.

INTRODUCTION: Laparoscopic pyeloplasty has achieved good cosmetic and functional outcomes. Both transumbilical single-site and transumbilical multi-port approaches are currently being used. No comparison of transumbilical single-site laparoscopic pyeloplasty (TSLP) and transumbilical multi-port laparoscopic pyeloplasty (TMLP) has been reported in the literature. OBJECTIVES: We present a retrospective comparison study to evaluate clinical outcomes of TSLP and TMLP for children with ureteropelvic junction obstruction (UPJO). STUDY DESIGN: A retrospective study was carried out comparing TSLP and TMLP performed by a single surgeon between July 2012 and June 2014. The patient data of the two groups (90 in each group) were evaluated. All patients underwent urine analysis, ultrasonography, magnetic resonance urography, and diuretic renogram using 99Tc-diethylene triamine pentaacetic acid scan preoperative and postoperative follow-up. Data were analyzed using the SPSS 20.0 software package. RESULTS: DISCUSSION: To our knowledge, our series is the first report in the literature that compares the outcomes of TSLP and TMLP in children. Our study suggested that there were no significant differences in start of oral feeding, drain removal, hospital stay, postoperative renal pelvic anteroposterior diameter and differential renal function at 6 months, postoperative complications, and success rate between the two groups. It demonstrated that TMLP is as effective and safe as TSLP. Although the cosmetic result of the TSLP group is satisfactory, TMLP requires three 0.5-cm ports around the umbilicus and does not change the shape of the umbilicus. Hence, the cosmetic result of the TMLP group is better than that of the TSLP group. TSLP involves some technical challenges. However, TMLP facilitates the procedure and renders the operation easier. Our findings confirmed that the operative time of TMLP group is shorter than that in TSLP group, and also showed that TMLP is relatively easy to perform compared with TSLP. CONCLUSION: TMLP is a feasible and safe operation for pediatric UPJO. TMLP is shorter in operative time and has a better cosmetic result than TSLP. We propose TMLP as a more viable treatment option for pediatric UPJO.

Early experience of using transumbilical multi-stab laparoscopic pyeloplasty for infants younger than 3 months.

OBJECTIVE: Minimally invasive surgery is increasingly being adopted in pediatric urology practice. The aim of this study is to investigate the feasibility and the safety of transumbilical multi-stab laparoscopic pyeloplasty (TMLP) as a treatment for infants younger than 3 months with severe hydronephrosis. METHODS: We retrospectively reviewed 63 infants younger than 3 months with severe hydronephrosis who underwent TMLP from June 2010 to March 2013. The operative indications included: 1) prenatal diagnosis of hydronephrosis with anteroposterior renal pelvic diameter greater than 3 cm and Society of Fetal Urology (SFU) Grade 4 hydronephrosis; 2) ipsilateral differential renal function being less than 40%. Patients were followed up with physical examinations, ultrasound and radionuclide scans. RESULTS: The operations were successfully performed in all 63 patients. There was no conversion, no requirement of additional trocar placement and no intraoperative complication. The median age was 54 (47-87) days. The median operative time was 75 (53-118) minutes. The patients were followed up for 12 (6-36) months. The anastomoses were proved to be patent and the renal parenchymal thickness increased. The renal pelvic anteroposterior diameters were reduced and the renal functions were improved (p < 0.01). In addition, the scars were barely noticeable. CONCLUSIONS: TMLP for infants younger than 3 months with severe hydronephrosis is feasible, safe and minimally invasive. The cosmetic results are excellent.

Transumbilical single-incision laparoscopic versus conventional laparoscopic upper pole heminephroureterectomy for children with duplex kidney: a retrospective comparative study.

OBJECTIVE: To present our experience regarding transumbilical single-incision laparoscopic heminephroureterectomy (SILH) in children with duplex kidney anomalies, and to investigate its feasibility and safety compared with those of conventional laparoscopic heminephroureterectomy (CLH). MATERIALS AND METHODS: A matched-pair study comparing 34 SILHs and 34 CLHs performed by a single surgeon from 2007 to 2013 was presented. All SILHs were performed through a 2-cm periumbilical incision by using the port-access system, whereas CLH cases were performed via a transperitoneal 3-port approach. The groups were matched for age, gender, weight, laterality, and surgical indication of the patients. Data including demographics and perioperative and short-term outcomes of the patients were retrospectively compared. RESULTS: The 2 groups were comparable in demographics, and surgical indications of the patients (P >.05). No significant difference was observed between SILH and CLH cases in terms of median operative time (105 vs 97 minutes; P = .06), estimated blood loss (22 vs 25 mL; P = .91), interval for oral intake (12 vs 12 hours; P = .69), analgesic requirement (9 vs 6 cases; P = .38), transfusion rate (0% for both; P = 1.00), complication rate (2.9% vs 0%; P = 1.00), postoperative hospital stay (5.0 vs 4.5 days; P = .59), and renal functional loss of the operated side at 3 months after surgery (5.4% vs 5.2%; P = .60). CONCLUSION: SILH is feasible and safe in the hands of an experienced pediatric laparoscopic surgeon. Although the outcomes were comparable, better subjective cosmetic results of SILH were achieved.

Laparoscopic excision of choledochal cyst and Roux-en-Y hepaticojejunostomy in symptomatic neonates.

PURPOSE: Choledochal cysts require surgical excision, preferably before the onset of cholangitis. Recently, it has become feasible to accomplish the excision laparoscopically in adults and older children. Yet, whether laparoscopic excision of choledochal cyst can be performed safely in symptomatic neonates with choledochal cyst is unclear. We herewith reviewed our experience of laparoscopic excision of choledochal cysts in neonates. METHODS: We managed 9 neonates with choledochal cysts between April 2003 and February 2007. The choledochal cysts were excised laparoscopically. The Roux-en-Y hepaticojejunostomy was fashioned extracorporeally by exteriorizing the jejunum through the extended umbilical port site. End-to-side anastomosis between the common hepatic duct stump and Roux loop was carried out intracorporeally. The patients were followed up for an average of 26 months. RESULTS: The patients presented with jaundice, pale stool, and deranged liver function tests. The diagnosis was confirmed with ultrasonography postnatally. The median operation time was 3.6 hours. There was no operative complication and no conversion. The blood loss was minimal. The recovery was uneventful, and the median hospital stay was 6 days. The liver function tests normalized 3 to 16 weeks postoperatively. No complication was detected at the follow-up visits. CONCLUSIONS: Our preliminary results show that laparoscopic excision of choledochal cyst and Roux-en-Y hepaticojejunostomy in neonates is both feasible and safe. It curtails further complication of the cysts and reverses the derangement of liver function. In addition, the laparoscopic approach minimizes surgical trauma.