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To describe a novel modification of technique to improve efficacy of robot-assisted laparoscopic extravesical ureteral reimplantation (RALUR-EV) in infants.Between April 2017 and July 2019, sixteen infants with primary obstructive megaureter (POM) (Age range: 4-12 months) underwent robot-assisted ureteral reimplantation were reviewed in this series. In addition to the conventional Lich-Gregoir technique, the detrusor tunnel has been extended to the mobilized anterior bladder wall to guarantee sufficient tunnel length/ureter diameter ratio and avoid ureteral angulation. All patients underwent repeated ultrasound, diuretic renal dynamic imaging and voiding cystourethrography (VCUG) perioperatively and the outcomes were documented.All operations were completed with robotic assisted approach without conversion. Bilateral and unilateral reimplantation were respectively performed in two and fourteen patients. The mean operative time was 115.0 ± 19.5 min and the mean blood loss was 10.0 ± 1.8 ml. There were no high-grade complications (III-IV on Clavien-Dindo classification) except for one patient. The distal ureteric diameter was reduced from pre operative 1.7 ± 0.5 to 0.6 ± 0.5 cm 6 months post operatively (p 0.05). One child (6.3%) required the second reimplantation for stenosis. The overall operative success rate was 94.4% (17 of 18 ureters) with a mean follow-up of 15.9 ± 7.4 months with no flux detected.Our preliminary experience suggests that our modified robot-assisted laparoscopic extravesical ureteral reimplantation is feasible in infants with good results.

Weak correlation between gamma passing rates and dose differences in target volumes and organs at risk (OARs) has been reported in several studies. Evaluation on the differences between planned dose-volume histogram (DVH) and reconstructed DVH from measurement was adopted and incorporated into patient-specific quality assurance (PSQA). However, it is difficult to develop a methodology allowing the evaluation of errors on DVHs accurately and quickly.To develop a DVH-based pretreatment PSQA for volumetric modulated arc therapy (VMAT) with combined deep learning (DL) and machine learning models to overcome the limitation of conventional gamma index (GI) and improve the efficiency of DVH-based PSQA.A DL model with a three-dimensional squeeze-and-excitation residual blocks incorporated into a modified U-net was developed to predict the measured PSQA DVHs of 208 head-and-neck (HN) cancer patients underwent VMAT between 2018 and 2021 from two hospitals, in which 162 cases was randomly selected for training, 18 for validation, and 28 for testing. After evaluating the differences between treatment planning system (TPS) and PSQA DVHs predicted by DL model with multiple metrics, a pass or fail (PoF) classification model was developed using XGBoost algorithm. Evaluation of domain experts on dose errors between TPS and reconstructed PSQA DVHs was taken as ground truth for PoF classification model training.The prediction model was able to achieve a good agreement between predicted, measured, and TPS doses. Quantitative evaluation demonstrated no significant difference between predicted PSQA dose and measured dose for target and OARs, except for DThe successful prediction of PSQA doses and classification of PoF for HN VMAT PSQA indicating that this DVH-based PSQA method is promising to overcome the limitations of GI and to improve the efficiency and accuracy of VMAT delivery.

This review highlights recent progress in single-atom electrocatalysts for highly efficient HERs including synthesis and characterization methods, recent advances and feasible design strategies.

Single-atom catalysts (SACs) with high activity, unique selectivity, and nearly 100% atom utilization efficiency are promising for broad applications in many fields. This review aims to provide a summary of the current development of SACs and point out their challenges and opportunities for commercial applications in the energy process. The discussion starts with an introduction of various types of SACs materials, followed by typical SACs synthetic methods with concrete examples and commonly used characterization methods. The state-of-the-art synthesis methods, whereby SACs with stabilized single metal atoms on the substrate without migration and agglomeration could be obtained, are emphasized. Next, we give an overview of different types of substrates and discuss the effects of substrate species on the structure and properties of SACs. Then we highlight the typical applications of SACs and the remaining challenges. Finally, a perspective on the opportunities for the development of SACs for future commercial applications is provided.

Due to the high theoretical specific capacity and low cost, FeF3·0.33H2O has become one of the potential choices of cathode materials for sodium-ion batteries. However, the poor intrinsic conductivity limits its practical applications. Herein, the atomic substitution is used to improve its intrinsic conductivity. The first-principles calculation results show that Cr3+ doping can reduce the band gap of FeF3·0.33H2O to improve its intrinsic conductivity. The discharge specific capacity of Fe0.95Cr0.05F3·0.33H2O with a narrowest band gap is 194.02 mA h/g at 0.1 C within the range of 1.4-4.0 V, which is higher than that of FeF3·0.33H2O (136.47 mA h/g). Using the electrochemical impedance spectroscopy and galvanostatic intermittent titration technique tests, it is found that Rct of Fe0.95Cr0.05F3·0.33H2O is reduced and DNa+ is almost unchanged, as compared to FeF3·0.33H2O.

The development of catalysts free of platinum-group metals with a high performance for the oxygen reduction reaction (ORR) in proton exchange membrane fuel cells is a grand challenge. Herein, we re...

An accurate and reliable target volume delineation is critical for the safe and successful radiotherapy. The purpose of this study is to develop new 2D and 3D automatic segmentation models based on RefineNet for clinical target volume (CTV) and organs at risk (OARs) for postoperative cervical cancer based on computed tomography (CT) images.A 2D RefineNet and 3D RefineNetPlus3D were adapted and built to automatically segment CTVs and OARs on a total of 44 222 CT slices of 313 patients with stage I-III cervical cancer. Fully convolutional networks (FCNs), U-Net, context encoder network (CE-Net), UNet3D, and ResUNet3D were also trained and tested with randomly divided training and validation sets, respectively. The performances of these automatic segmentation models were evaluated by Dice similarity coefficient (DSC), Jaccard similarity coefficient, and average symmetric surface distance when comparing them with manual segmentations with the test data.The DSC for RefineNet, FCN, U-Net, CE-Net, UNet3D, ResUNet3D, and RefineNet3D were 0.82, 0.80, 0.82, 0.81, 0.80, 0.81, and 0.82 with a mean contouring time of 3.2, 3.4, 8.2, 3.9, 9.8, 11.4, and 6.4 s, respectively. The generated RefineNetPlus3D demonstrated a good performance in the automatic segmentation of bladder, small intestine, rectum, right and left femoral heads with a DSC of 0.97, 0.95, 091, 0.98, and 0.98, respectively, with a mean computation time of 6.6 s.The newly adapted RefineNet and developed RefineNetPlus3D were promising automatic segmentation models with accurate and clinically acceptable CTV and OARs for cervical cancer patients in postoperative radiotherapy.

Multi‐isocenter volumetric modulated arc therapy (VMAT) is recommended for craniospinal irradiation (CSI) to smooth the dose distribution in the junction regions relying solely on inverse optimization. However, few studies have measured the dosimetric impact of setup errors on this multi‐isocenter VMAT in the junction areas. The purpose of this study is to evaluate the impact of positional errors during VMAT CSI with two‐dimension (2D) and three‐dimension (3D) dosimetric measurements. A total of 20 patients treated by three‐isocenter VMAT CSI were retrospectively reviewed and analyzed. A 3D diode array ArcCHECK and radiochromic film EBT3 were applied to measure the percentage gamma passing rates (%GPs) and dose distributions in the junction areas between the cranial/upper‐spinal and the upper/lower‐spinal fields with intentionally introduced setup errors of ± 1 mm, ±2 mm, ±3 mm, ±5 mm, and ± 8 mm, respectively. The length and volume of planning target volume (PTV) for these CSI patients ranged from 50.14 to 80.8 cm, and 1572.3 to 2114.5 cm3, respectively. The %GPs for ±3 mm, ±5 mm, and ±8 mm positional errors were around 95%, 90%, and 85%, respectively, in the junction areas. The dosimetric verification results with EBT3 films indicated that cold and hot areas were observed with the increase of introduced setup errors. In conclusion, the dosimetric verification with intentionally introduced setup errors demonstrated that positional errors within 3 mm have a little impact for VMAT CSI, although setup errors should be minimized. Relying on the inverse optimization of VMAT to smooth the dose distribution in the junction areas is feasible for CSI.

Objective To research and assess automatic volumetric modulated arc therapy (VMAT) planning methods for patients with intraocular cancer. Methods The mdaccAutoPlan system was added to the Pinnacle3 treatment planning system as a plug‐in. Automatic VMAT plans were generated for 10 patients diagnosed with intraocular cancer, and evaluated according to standard dose‐volume histogram parameters. Results The planning target volume of enrolled patients ranges from 14.24 to 50.69 cm3. Both planning methods lead to acceptable planning target volume target coverage with a V95 of 97.9 ± 1.4% and 96.4 ± 1.5% for manual and automatic plans (P = 0.03), respectively. Automatic planning lowered the dose delivered to the ipsilateral lens and optical nerves, but increased the dose to the brainstem compared with manual planning. Automatic planning significantly prolonged VMAT planning time (3.25 ± 0.53 h vs. 1.02 ± 0.69 h, P

Herein, strongly coupled Mo2C and Ni nanoparticles with in-situ formed interfaces encapsulated by porous carbon nanofibers (Ni-Mo2C-CNF) have been rationally fabricated via pyrolyzing electrospinning polyvinyl alcohol fibers containing hydrothermally obtained NiMoO4 under Ar atmosphere and applied as high-performance and stable electrocatalyst for HER in alkaline electrolytes. Powered by NiMoO4 as homologous bimetallic precursor, the Ni-Mo2C-CNF possesses numerous in-situ formed Ni-Mo2C interfaces, which facilitates the synergistic effect between Ni and Mo2C, improving the conductivity and thus boosting the electrocatalytic performance towards HER. In the meantime, the porous carbon nanofibers with well encapsulated Ni-Mo2C active components stacks, constituting conductive network, which promotes the mass transport, electron transfer, active sites exposure and electrocatalytic stability. As a result, the Ni-Mo2C-CNF features prominently in HER, as it demands a low overpotential of 196 mV but is able to stably yield the current density of 10 mA cm−2 with a small Tafel plot of 54.7 mV dec−1. The method demonstrated in our work to synthesize bimetallic heterostructured materials will offer valuable inspiration to construct promising non-precious electrocatalysts for diverse vital renewable energy applications.

To investigate the feasibility and accuracy of radiomics models based on contrast-enhanced CT (CECT) in the prediction of perineural invasion (PNI), so as to stratify high-risk recurrence and improve the management of patients with gastric cancer (GC) preoperatively.Total of 154 GC patients underwent D2 lymph node dissection with pathologically confirmed GC and preoperative CECT from an open-label, investigator-sponsored trial (NCT01711242) were enrolled. Radiomics features were extracted from contoured images and selected using Mann-Whitney U test and the least absolute shrinkage and selection operator (LASSO) after inter-class correlation coefficient (ICC) analysis. Models based on radiomics features (R), clinical factors (C) and combined parameters (R + C) were built and evaluated using Support Vector Machine (SVM) and logistic regression to predict the PNI for patients with GC preoperatively.Total of 11 radiomics features were selected for final analysis, along with two clinical factors. The area under curve (AUC) of models based on R, C, and R + C with logistic regression and SVM were 0.77 vs. 0.83, 0.71 vs.0.70, 0.86 vs. 0.90, and 0.73 vs.0.80, 0.62 vs. 0.64, 0.77 vs. 0.82 in the training and testing cohorts, respectively. SVM(R + C) achieved a best AUC of 0.82(0.69-0.94) in the test cohorts with a sensitivity, specificity and accuracy of 0.63, 0.91, and 0.77, respectively.The performance of these models indicates that radiomics features alone or combined with clinical factors provide a feasible way to classify patients preoperatively and improve the management of patients with GC.

To evaluate the clinical efficacy of Compound Chamomile and Lidocaine Hydrochloride Gel for postoperative hypospadias in children.From January to December 2020, we treated 116 children with distal hypospadias in the Department of Urology, Department of Pediatrics and the Seventh Medical Center of the PLA General Hospital, 58 by primary Snodgrass urethroplasty only (the control group) and the other 58 with Compound Chamomile and Lidocaine Hydrochloride Gel smeared on the penis postoperatively in addition (the trial group). We compared the operation time and postoperative pain score, edema regression and incidence of infection between the two groups, followed by statistical analysis using T test and Chi-square test.All the operations were successfully completed by the same surgeon under general anesthesia. There were no statistically significant differences between the trial and control groups in age (［2.5 ± 0.8］ vs ［2.4 ± 0.6］ yr, P0.05) or operation time (［95.6 ± 14.5］ vs ［97.1 ± 15.2］ min, P0.05). No incision infection occurred in any of the cases. The pain scores at dressing removal were remarkably lower in the trial than in the control group at 2 hours (1.4 ± 1.0 vs 2.6 ± 1.3, P0.05), 24 hours (2.2 ± 1.3 vs 3.9 ± 1.6, P0.05), 48 hours (1.2 ± 0.7 vs 1.6 ± 0.9, P0.05) and 72 hours after surgery (2.5 ± 0.8 vs 3.7 ± 1.8, P0.05). Significantly more cases of edema regression were achieved in the trial than in the control group at 2 weeks postoperatively (35 vs 19, P0.05).Compound Chamomile and Lidocaine Hydrochloride Gel can effectively relieve pain, reduce edema and accelerate edema regression after surgery in children with hypospadias, and therefore deserves wide clinical application.、.

Achieving a highly efficient and durable methanol electro-oxidation catalyst in acid media is critical for the practical utilization of direct methanol fuel cells (DMFCs) at the commercial scale. Herein, we report a facile and effective one-pot strategy for the synthesis of carbon-supported PtCu alloy nanoparticles (PtCu NPs) with a Pt-rich surface, small particle size, and uniform dispersion. The as-prepared PtCu NPs with optimal alloy composition (Pt2Cu) exhibit significantly improved electrochemical methanol oxidation reaction performance in terms of high activity, superior CO tolerance, and remarkable durability in contrast to those of commercial Pt/C catalysts in acid media. Particularly, the Pt2Cu/C catalyst exerts 4.5 times enhancement in the mass activity and a larger If/Ib value compared to commercial Pt/C (Pt/Ccomm). The enhanced catalytic activities can be ascribed to the high utilization of Pt and the high index facets of the surface. Besides, the addition of Cu downshifts the d-band center of Pt, and improves CO tolerance during the methanol oxidation reaction process. This work provides an efficient strategy for designing desired Pt-based alloy for various catalytic reactions.

The potential of converting traditional biomass into low-cost HER catalysts has broad application prospects. In this paper, fungus is used as a carbon-based carrier. The bimetallic catalyst RuM-C (M = V, Mo, W, Zn, Cu) was synthesized under inert gas protection at high temperature. The order of electrocatalytic activity is RuV-C > RuZn-C > RuW-C > RuMo-C > Ru-C > RuCu-C > BF-C, which indicates that RuV-C exhibits excellent HER activity. Due to its irregular sheet structure, the specific surface area of the catalyst is increased. Impressively, it exhibits extremely high catalytic activity for HER in 1 M KOH due to favorable kinetics and excellent specific activity. Consequently, the prepared RuV-C exhibited excellent and stable HER activity compared Ru-C with a low overpotential of 65.78 mV at the current densities of 10 mA cm−2 and Tafel slope of 45.26 mV dec−1. The potential only decreased by 88 mV after 24 h of continuous testing, which indicates that the catalyst has outstanding stability. This work will provide positive inspiration for the promotion of a new Ru-based biomass HER electrocatalyst.

Due to the high theoretical specific capacity and low cost, FeF

Background Controversial conclusions had been reported in studies trying to confirm the impact of heart dose on overall survival (OS) reported in RTOG 0167 for non-small cell lung cancer (NSCLC) patients who underwent radiotherapy (RT). The purpose of this study is to investigate the association of lung and heart dosimetric parameters with OS in NSCLC patients treated by volumetric modulated arc therapy (VMAT). Methods Inoperable NSCLC patients treated by VMAT from March 2012 to December 2015 were retrospectively reviewed. OS and progression-free survival (PFS) were estimated with the Kaplan-Meier method. Univariate and multivariate analyses were conducted with Cox proportional hazards model. Multivariate model building was conducted using stepwise regression for variables with p-value smaller than 0.2 in the univariate analysis. Results There were 130 NSCLC patients enrolled in this study with a median age of 63 years (range from 34 to 82 y). The median prescription dose for these patients was 56 Gy (range 40-70 Gy) with a mean heart and lung dose of 14.8±8.5 Gy and 13.6±4.4 Gy, respectively. The rates of patients with above grade III radiation pneumonitis (RP) and fibrosis were 8.5% and 8.5%, respectively. The 2-year PFS and OS of these patients were 15.2% and 39.8%, with a median PFS and OS of 7.2 and 18.8 months, respectively. RP was correlated with OS (p=0.048) and lung V20 was associated with PFS (p=0.04) according to the univariate analysis. Multivariate analysis demonstrated that RP (HR 1.39, 95%CI 1.010-1.909, p=0.043) and heart V15 (HR 1.02, 95%CI 1.006-1.025 p=0.002) were progression factors of OS, and no factor was associated with PFS. Conclusions RP and heart V15 were associated with OS for patients with stage III NSCLC who underwent VMAT. Heart and lung dosimetric parameters were highly correlated with each other, sparing of heart and lung should be considered equally during the treatment planning.

Ruthenium (Ru) as a cheaper alternative to Pt has been studied as a viable alternative for the hydrogen evolution reaction (HER) catalyst, however, no single-atom Ru catalyst has been reported for the HER electrocatalysis. Herein, we design and develop the first type of single-atom Ru based catalyst applied for the HER under pH-universal conditions. This binder-free catalyst consists of single Ru atoms anchored to the surface of MoS2 nanosheets array supported by a carbon cloth (Ru-MoS2/CC, Ru in Ru-MoS2: 0.37 wt%). The abundant dispersed single Ru atoms are highly catalytically active, and the MoS2 array supported 3D porous structure offers more opportunities for active sites and serves as co-catalysts for synergetic catalysis, with accompanying enhanced the electrical conductivity of this array-catalyst. Remarkably, the Ru-MoS2/CC exhibits extremely enhanced catalytic activity compared to that of MoS2/CC and possesses good long-term stability. Density functional theory calculations revealed that the improved catalytic activities stem from the synergistic effect between MoS2 and single-atom Ru. This discovery holds a great potential to accelerate the large-scale binder-free application of single Ru atoms in industry.

The SiO2/WO3/NiWO4 composites modified carbon nanofibers (SiWNi-CNFs) were prepared by a facile electrospinning method with following carbonization process under nitrogen atmosphere. The as-obtained SiWNi-CNFs were characterized by transmission electron microscope (TEM), scanning electron microscope (SEM), X-ray photoelectron spectra (XPS), X-ray powder diffraction (XRD), FT-IR spectroscopy and Raman spectroscopy. As revealed by the electrochemical measurement, the SiWNi-CNFs prepared with SiW12/NiAc2 molar ratio of 1:1 presented best hydrogen evolution activity with a small Tafel slope (48 mV dec−1) among all the as-prepared samples. Notably, the as-prepared catalysts exhibit a small onset potential (0.29 V vs. reversible hydrogen electrode), high current density and excellent stability. The experimental results pointed that the SiWNi-CNFs processes more efficient hydrogen evolution properties than that other contrast samples. This is due to the SiO2/WO3/NiWO4 composite modified on the surface of carbon nanofibers can generate numerous active sites from the synergistic effect of each component. At the same time, the intimate combination of ternary oxide and carbon nanofibers can accelerate the electron transfer, enhance the stability and hinder the aggregation of active components during the carbonization. Moreover, the net-like structure stacked by carbon nanofibers should render the exposure of active sites and facilitate the mass transport for the HER process.

In this work, carbon microfibers modified with Mo2C and metallic Ni (Mo2C-Ni-CMF0.2) was successfully synthesized by one-step strategy and demonstrated that it is efficient and stable low-cost electrocatalyst for hydrogen evolution reaction (HER) in acidic conditions. The as-obtained Mo2C-Ni-CMF0.2 shows excellent HER activity with a low overpotential (131 mV) to reach current density of 10 mA cm−2, a small Tafel plot (34.1 mV dec−1) and remarkable stability. The carbonized cotton fibers has a pore structure and a large specific surface area, which is beneficial for improving electrocatalytic activity. Moreover, cotton fibers also provide a carbon source for the formation of Mo2C during carbonization. The catalyst owes better activity to the electrion transmission facilitated by the synergy between Mo2C and Ni, and the adsorption of H+ based on pore structure.

Herein, Ni17W3 nanoparticles (NPs) decorated WO2 nanohybrid supported by Ni foam (Ni17W3/WO2/NF) is successfully prepared via annealing Ni4W6O21(OH)2·4H2O/NF under reductive atmosphere and applied ...

Exploring highly active, inexpensive and robust electrocatalysts for oxygen reduction reaction (ORR) is of great significance as a competitive alternative to noble metal-based catalysts in energy conversion and storage devices. In the present study, we design a novel ORR electrocatalyst of iron-cobalt (FeCo) alloy nanoparticles embedded on N-doped porous carbon nanofibers (FeCo@PCNF-T) by electrospinning of [Polyacrylonitrile (PAN)/Prussian blue analogues/CaCO3] and post-calcination treatment. The obtained catalysts with bimetallic active sites show unique three-dimensional (3D) hierarchical meso/macropores structures. FeCo alloy nanoparticles are encapsulated into graphitic carbon that can increase stability and provide additional catalytic active sites. Under the optimized condition, FeCo@PCNF-800 displays excellent ORR electrocatalytic activity in alkaline solutions, with a more positive half-wave potential (E1/2 of 0.854 V vs RHE) and larger limited-diffusion current density (j of 6.012 mA cm−2) than those of 20 wt% Pt/C (E1/2 of 0.849 V and j of 5.710 mA cm−2). In addition, FeCo@PCNF-800 also exhibits comparable ORR electrocatalytic activity in acidic solutions to those of 20 wt% Pt/C with onset potential and half-wave potential as more positive as 0.843 V vs RHE and 0.739 V vs RHE, respectively. Moreover, FeCo@PCNF-800 exhibits excellent tolerance towards methanol, stability and a four-electron pathway in both basic and acidic solutions. The excellent ORR electrocatalytic activity performance of FeCo@PCNF-800 is attributed to the synergistic effect of the FeCo alloy nanoparticles and N-doped porous carbon nanofibers. The synergistic effect can improve the mass and charge transport capability and increase active sites of FeCo-N-C. Furthermore, this work offers a new insight for the reasonable design and development of efficient non-noble metal electrocatalysts for challenging electrochemical energy-related technologies.

Background: Published data on the effects and toxicities of volumetric modulated arc therapy (VMAT) in the management of inoperable lung cancer are scarce. Materials and methods: The clinical outcomes and pulmonary toxicities of 134 patients with consecutive inoperable lung cancer who underwent VMAT from March 2011 to September 2016 were retrospectively reviewed. The dosimetric and characteristic factors associated with acute radiation pneumonitis (RP) and pulmonary fibrosis were evaluated with univariate and multivariate analysis. Results: The average prescription doses to these 134 patients were 57.07±6.27 Gy (range 52-64 Gy). The overall median follow-up time was 18.6 months (range, 2-45 mo), with a median follow-up time for the surviving patients of 20 months (range, 7-45 mo). The 2-year progression-free survival (PFS) and overall survival (OS) for all patients were 18.2% and 38.4%, with a median PFS and OS of 7.6 months and 18.6 months, respectively. The percent of patients with grade III/higher RP and pulmonary fibrosis were 10.5% and 9.0%, respectively. V13 (p=0.02) and age (p=0.02) were independently associated with acute RP according to multivariate analysis. The constraints for lung dosimetric metrics V10,V13,V20 and V30 were approximately 49%,41%,26% and 17% in VMAT treatment of lung cancer to limit the RP rate < 10%. Conclusion: VMAT can be delivered safely with acceptable acute and late toxicities for lung cancer patients. Lung dosimetric metrics were valuable in predicting acute RP. A lung V13 constraint of 40% was helpful to limit the RP rate < 10% in VMAT treatment of lung cancer patients.

When drilling difficult-to-cut materials with twist drills, drill wear frequently occurs with various types including flank wear, crater wear, chisel wear and outer corner wear. The previous research mainly focuses on flank wear. This study presents a mechanistic drilling force model of worn drill with the drill wear effect coefficients (DWECs) to describe the effect of different wear types on drilling forces. The DWECs under different drill wear types are calibrated and analyzed through a group of carefully designed experiments. It believes the proposed model together with the results are useful in drill wear detection.