FREE GRAFT TWO-STAGE URETHROPLASTY FOR HYPOSPADIAS REPAIR

Objective To evaluate the effectiveness of free graft transplantation two-stage urethroplasty for hypospadias repair. Methods Fifty-eight cases with different types of hypospadias including 10 subcoronal, 36 penile shaft, 9 scrotal, and 3 perineal were treated with free full-thickness skin graft or (and) buccal mucosal graft transplantation two-stage urethroplasty. Of 58 cases, 45 were new cases, 13 had history of previous failed surgeries. Operative procedure included two stages: the first stage is to correct penile curvature (chordee), prepare transplanting bed, harvest and prepare full-thickness skin graft, buccal mucosal graft, and perform graft transplantation. The second stage is to complete urethroplasty and glanuloplasty. Results After the first stage operation, 56 of 58 cases (96.6%) were successful with grafts healing well, another 2 foreskin grafts got gangrened. After the second stage operation on 56 cases, 5 cases failed with newly formed urethras opened due to infection, 8 cases had fistulas, 43 (76.8%) cases healed well. Conclusions Free graft transplantation two-stage urethroplasty for hypospadias repair is a kind of effective treatment with broad indication, comparatively high success rate, less complications and good cosmatic results, indicative of various types of hypospadias repair.

Two-Stage Optimal Scheduling of Community Integrated Energy System

From the perspective of a community energy operator,a two-stage optimal scheduling model of a community integrated energy system is proposed by integrating information on controllable loads.The day-ahead scheduling analyzes whether various controllable loads participate in the optimization and investigates the impact of their responses on the operating economy of the community integrated energy system(IES)before and after;the intra-day scheduling proposes a two-stage rolling optimization model based on the day-ahead scheduling scheme,taking into account the fluctuation of wind turbine output and load within a short period of time and according to the different response rates of heat and cooling power,and solves the adjusted output of each controllable device.The simulation results show that the optimal scheduling of controllable loads effectively reduces the comprehensive operating costs of community IES;the two-stage optimal scheduling model can meet the energy demand of customers while effectively and timely suppressing the random fluctuations on both sides of the source and load during the intra-day stage,realizing the economic and smooth operation of IES.

Solar-assisted two-stage catalytic membrane reactor for coupling CO_(2) splitting with methane oxidation reaction

A two-stage catalytic membrane reactor(CMR)that couples CO_(2) splitting with methane oxidation reactions was constructed based on an oxygen-permeable perovskite asymmetric membrane.The asymmetric membrane comprises a dense SrFe_(0.9)Ta_(0.1)O_(3-σ)(SFT)separation layer and a porous Sr_(0.9)(Fe_(0.9)Ta_(0.1))_(0.9)Cu_(0.1)O_(3-σ)(SFTC)catalytic layer.In thefirst stage reactor,a CO_(2) splitting reaction(CDS:2CO_(2)→2CO+O_(2))occurs at the SFTC catalytic layer.Subsequently,the O_(2) product is selectively extracted through the SFT separation layer to the permeated side for the methane combustion reaction(MCR),which provides an extremely low oxygen partial pressure to enhance the oxygen extraction.In the second stage,a Sr_(0.9)(Fe_(0.9)Ta_(0.1))_(0.9)Ni_(0.1)O_(3-σ)(SFTN)catalyst is employed to reform the products derived from MCR.The two-stage CMR design results in a remarkable 35.4%CO_(2) conversion for CDS at 900℃.The two-stage CMR was extended to a hollowfiber configuration combining with solar irradiation.The solar-assisted two-stage CMR can operate stably for over 50 h with a high hydrogen yield of 18.1 mL min^(-1) cm^(-2).These results provide a novel strategy for reducing CO_(2) emissions,suggesting potential avenues for the design of the high-performance CMRs and catalysts based on perovskite oxides in the future.

Two-Stage Planning of Distributed Power Supply and Energy Storage Capacity Considering Hierarchical Partition Control of Distribution Network with Source-Load-Storage

Aiming at the consumption problems caused by the high proportion of renewable energy being connected to the distribution network,it also aims to improve the power supply reliability of the power system and reduce the operating costs of the power system.This paper proposes a two-stage planning method for distributed generation and energy storage systems that considers the hierarchical partitioning of source-storage-load.Firstly,an electrical distance structural index that comprehensively considers active power output and reactive power output is proposed to divide the distributed generation voltage regulation domain and determine the access location and number of distributed power sources.Secondly,a two-stage planning is carried out based on the zoning results.In the phase 1 distribution network-zoning optimization layer,the network loss is minimized so that the node voltage in the area does not exceed the limit,and the distributed generation configuration results are initially determined;in phase 2,the partition-node optimization layer is planned with the goal of economic optimization,and the distance-based improved ant lion algorithm is used to solve the problem to obtain the optimal distributed generation and energy storage systemconfiguration.Finally,the IEEE33 node systemwas used for simulation.The results showed that the voltage quality was significantly improved after optimization,and the overall revenue increased by about 20.6%,verifying the effectiveness of the two-stage planning.

Two-stage urethroplasty is a better choice for proximal hypospadias with severe chordee after urethral plate transection： a single-center experience

It is still debatable whether single- or two-stage urethroplasty is a more suitable technique for treating hypospadias with severe chordee after urethral plate transection. This retrospective study evaluated these two techniques. A total of 66 patients of proximal hypospadias with severe chordee were divided into two groups according to the techniques they underwent： 32 and 34 patients underwent single-stage （Duckett） or two-stage urethroplasty, respectively. Median ages at presentation were 7.5 years and 11.0 years in single-stage and two-stage repair groups, respectively. Median follow-ups were 28.5 months （20-60 months） and 35 months （18-60 months） in the single-stage and two-stage groups, respectively. The meatus of the neourethra was located at the top of the glans in all patients. No recurrence of chordee was found during follow-up, and all patients or parents were satisfied with the penile length and appearance. Complications were encountered in eight patients in both groups, with no statistically significant differences between the two techniques. The late complication rate of stricture was higher after the single-stage procedure （18.75% vs 0%）. The complication rate after single-stage repairs was significantly lower in the prepubescent subgroup （10.52%） than in the postpubescent cohort （46.15%）. These results indicate that the urethral plate transection effectively corrects severe chordee associated with proximal hypospadias during the intermediate follow-up period. Considering the higher rate of stricture after single-stage urethroplasty, two-stage urethroplasty is recommended for proximal hypospadias with severe chordee after urethral plate transection.

Influence of two-stage harvesting on the properties of cold-pressed rapeseed(Brassica napus L.)oils

Rapeseed(Brassica napus L.)harvesting method is critical since it significantly determines the seed yield,oil quality,and industrial efficiency.This study investigated the influences of harvesting methods on the quality of cold-pressed rapeseed oil of two varieties.Oil color,peroxide value(POV),tocopherol content,fatty acid composition,and polarity of total polyphenols(PTP)contents of two rapeseed varieties in Huanggang and Xiangyang were compared through artificially simulated combined harvesting and two-stage harvesting.Results showed significant differences in the quality of rapeseed oil between the two harvesting methods.The red value(R-value),POV,total tocopherol contents,linoleic and linolenic acid content,and PTP content of the pressed rapeseed oil prepared by the combined harvesting method were about 27.6,5.7,15.8,2.0,0.5,and 28.6%lower than those of the oil produced from the two-stage harvesting method,respectively.Xiangyang and Huayouza62 performed better in the two regions and two varieties,respectively.To sum up,the rapeseed oil obtained 41–44 days after final flowering of combined harvesting,35 days after final flowering,and six days of post-ripening of the two-stage harvesting had the best quality.

Tourism Route Recommendation Based on A Multi-Objective Evolutionary Algorithm Using Two-Stage Decomposition and Pareto Layering

Tourism route planning is widely applied in the smart tourism field.The Pareto-optimal front obtained by the traditional multi-objective evolutionary algorithm exhibits long tails,sharp peaks and disconnected regions problems,which leads to uneven distribution and weak diversity of optimization solutions of tourism routes.Inspired by these limitations,we propose a multi-objective evolutionary algorithm for tourism route recommendation(MOTRR)with two-stage and Pareto layering based on decomposition.The method decomposes the multiobjective problem into several subproblems,and improves the distribution of solutions through a two-stage method.The crowding degree mechanism between extreme and intermediate populations is used in the two-stage method.The neighborhood is determined according to the weight of the subproblem for crossover mutation.Finally,Pareto layering is used to improve the updating efficiency and population diversity of the solution.The two-stage method is combined with the Pareto layering structure,which not only maintains the distribution and diversity of the algorithm,but also avoids the same solutions.Compared with several classical benchmark algorithms,the experimental results demonstrate competitive advantages on five test functions,hypervolume(HV)and inverted generational distance(IGD)metrics.Using the experimental results of real scenic spot datasets from two famous tourism social networking sites with vast amounts of users and large-scale online comments in Beijing,our proposed algorithm shows better distribution.It proves that the tourism routes recommended by our proposed algorithm have better distribution and diversity,so that the recommended routes can better meet the personalized needs of tourists.

Multi-source coordinated stochastic restoration for SOP in distribution networks with a two-stage algorithm

After suffering from a grid blackout, distributed energy resources(DERs), such as local renewable energy and controllable distributed generators and energy storage can be used to restore loads enhancing the system’s resilience. In this study, a multi-source coordinated load restoration strategy was investigated for a distribution network with soft open points(SOPs). Here, the flexible regulation ability of the SOPs is fully utilized to improve the load restoration level while mitigating voltage deviations. Owing to the uncertainty, a scenario-based stochastic optimization approach was employed,and the load restoration problem was formulated as a mixed-integer nonlinear programming model. A computationally efficient solution algorithm was developed for the model using convex relaxation and linearization methods. The algorithm is organized into a two-stage structure, in which the energy storage system is dispatched in the first stage by solving a relaxed convex problem. In the second stage, an integer programming problem is calculated to acquire the outputs of both SOPs and power resources. A numerical test was conducted on both IEEE 33-bus and IEEE 123-bus systems to validate the effectiveness of the proposed strategy.

Two-stage revision in periprosthetic knee joint infections

Periprosthetic joint infection(PJI)following total knee arthroplasty is one of the most catastrophic and costly complications that carries significant patient wellness as well as economic burdens.The road to efficiently diagnosing and treating PJI is challenging,as there is still no gold standard method to reach the diagnosis as early as desired.There are also international controversies with respect to the best approach to manage PJI cases.In this review,we highlight recent advances in managing PJI following knee arthroplasty surgery and discuss in depth the two-stage revision method.

A two-stage but time-saving reconstructive scheme to treat severe lower limb length discrepancy:Two case reports

Limb length discrepancy(LLD)is a common orthopedic condition that can result in significant functional impairment,pain,and cosmetic deformities.Current reconstructive techniques for severe LLD are primarily based on callus distraction,which is a time-consuming process that can lead to complications,such as significant infection,joint stiffness,and stress fractures.To reduce the therapeutic time and minimize the risk of complications,we investigated the use of vascularized bone flaps as a technical supplement to callus distraction in the reconstruction of short limbs.We present two cases of severe LLD in the upper and lower legs,in which a twostage reconstruction approach was used.In the first stage,external fixation was applied to the affected limb to correct the soft tissue length and convert the short deformity into a bone defect.In the second stage,the bone defect was reconstructed using bilateral(patient A)or unilateral(patient B)free vascularized fibula bone grafts.Both patients had complete survival of the fibular grafts without stress fractures,and bone consolidation took 8 months(patient A)and 4 months(patient B).Compared to the traditional callus distraction,the two-stage approach was found to be more time-saving and reliable.The entire reconstructive scheme required 18 and 4 months for patients A and B,respectively,whereas the traditional callus distraction required 41 and 17 months,respectively.These findings suggest that the use of vascularized bone flaps as a technical supplement for callus distraction may provide an effective and efficient alternative for the treatment of severe LLD.Further studies are needed to validate these results and assess the long-term outcomes of this approach.

A New Two-Stage Tunable Space-Time Adaptive Detector

In order to improve the rejection capability of mismatched interferer signals,a new two-stage detector is proposed under homogeneous scenarios with unknown covariance matrix,which is obtained by cascading the adaptive matched filter(AMF)detector and the enhanced RAO(EnRAO)detector.The new detector has constant false alarm performance,and the closed-form expression of probability of false alarm and probability of detection is derived.The performance of the new detector is assessed,and analyzed in comparison with other detectors.The results show that,the proposed detector can provide enhanced rejection capability in the case of mismatch,but the performance of the detector is slightly lost under the condition of matching.

Analysis of the urethral stricture score and patient-related factors as predictors of outcomes following oral mucosal graft urethroplasty

Objective:The complexity of urethral strictures can predict outcomes following urethroplasty.The previously described urethral stricture score(U score)considered only stricture-related factors to grade the complexity of urethral strictures and to predict recurrence post urethroplasty,but not considered patient-related factors for the same.We aimed to study the correlation of both of these factors to the outcomes of oral mucosal graft urethroplasty.Methods:We retrospectively reviewed data of 101 patients who underwent oral mucosal graft urethroplasty in our institute with a minimum follow-up of 6 months.Baseline patient characteristics and stricture-related parameters were noted.The U score was calculated for all patients which consisted of the length,location,number,and etiology of stricture.Univariate and multivariate Cox proportional hazard regression models were used to determine significant risk factors of recurrence.Results:The mean follow-up of patients was 15 months.Recurrence was seen in 28 patients and the mean time for detection of recurrence was 8 months of follow-up.The Charlson Comorbidity Index,history of previous intervention,length of strictures,location of strictures,number of strictures,history of smoking,and etiology were independent predictors of recurrence following urethroplasty.Based on these parameters,we formulated the modified U score(MU score).The scores ranged from 0 to 6 and a score of>2 was found to be predictive of recurrence.On comparing receiver operating characteristic curves for both scores by the DeLong test,the MU score had larger area under the curve than the U score.Conclusion:The MU scoring system is the first of its kind attempt taking into consideration both patient-and stricture-related factors to predict recurrence following oral mucosal graft urethroplasty.

Stricture Free Survival after Urethroplasty: A 6-Year Malaysian Referral Centre Experience

Background: Urethroplasty is the gold standard for treatment for urethral strictures. We describe our results of urethroplasty and analyse the risk factors associated with stricture recurrence and stricture-free survival. Methods: A retrospective review of urethroplasty surgery carried out from 2016-2022. Patient records were analysed to obtain demographics, clinical, pathological and outcome data. Success of surgery is defined as postoperative Qmax > 15 ml/s or absence of any instrumentation of urethra such as urethral dilatation, after removal of urethral indwelling catheter. Results: A total of 66 patients who fulfilled the inclusion criteria were selected. Mean age was 43.8. Mean follow up was 27.2 ± 21.8 months. Stricture recurred in 18 patients (27.3%). Estimated stricture free survival time was 59.6 months (95% CI: 50.87 - 68.37). Previous surgical history for stricture was found to be predictive of stricture recurrence. After adjusting for age, BMI, aetiology of stricture and stricture length, previous surgical history had a risk of stricture recurrence approximately three times higher compared to those without. Conclusion: Previous surgical intervention for urethral stricture was found to be the most significant factor for stricture recurrence. We strongly advocate that the first curative surgery done for urethral strictures should be done in high volume centres and by experienced reconstructive urologists.

Evaluation of the Quality of Micturition in Patients Who Underwent Anastomotic Urethroplasty at the Yaounde Central Hospital, Cameroon

Introduction: Radiological investigation which is the gold standard to perform following anastomotic urethroplasty in order to evaluate the quality of micturition is costly. In our context, due to financial limitations, reconstructive urologists prefer to use the uroflowmetry in order to assess the micturition post-surgery. Therefore, the objective of the study was to assess the quality of micturition using the uroflowmetry after anastomotic urethroplasty. Methodology: We conducted an 11-year retrospective review (1st January 2006-31st December 2017) and a cross-sectional descriptive observational study for a period of 8 months (November 2017-June 2018) at the Urology and Andrology Department of the Yaounde Central Hospital (YCH) of patients who were diagnosed with urethral stenosis and underwent an anastomotic urethroplasty at the YCH. We excluded patients who had incomplete files, patients lost to follow-up and did not do pre-operative uroflowmetry. Quality of micturition was evaluated using a uroflowmetry. Data was analyzed using EPI info 7.0. Parametric variables were reported as means and standard deviations and percentages and counts were used to report categorical variables. Results: We had a sample of 60 patients. The mean age was 42 ± 5 years with extremes ranging from 20 to 76 years. Twenty-seven (27) patients, or 45%, had no post-operative complications, and those who did had a urinary tract infection (26.70%). In our series, we had 82% excellent results (patient satisfied with his urination with bell-shaped urinary stream and urinary flow greater than or equal to 15 ml/sec);15% good results (patient with moderate dysuria with average urinary stream and urinary flow between 10 and 14.9 ml/sec) and 3% poor results (severe dysuria with urinary flow less than 10 ml/sec, urinary retention or urinary incontinence). Based on these results we can say that the success rate in our series was 97%. 96.70% of patients were satisfied against 3.3% who were not. Conclusion: Anastomotic urethroplasty is the gold standard for the treatment of short urethral strictures. The results are good in the immediate and long term post-operative period. The use of the uroflowmetry as a screening tool for evaluating the quality of micturition after urethroplasty is effective.

Urethroplasty among Elderly Men, Surgical Techniques and Outcomes

Introduction: Urethroplasty remains the gold standard for the management of urethral stricture. However, the treatment of stricture disease in the elderly tends to be less invasive due to the presumption that they might not be able to stand long hours of surgery and might have higher rates of recurrence due to poor wound healing from microangiopathy. We present our experience with the outcomes of urethroplasty among elderly men seen at the Komfo Anokye Teaching Hospital from January 2012 to December 2021. Methods: This was a retrospective review of data captured in the urology database on all patients 65 years and above who underwent urethroplasty at the hospital over the study period. Data was obtained on patients’ demographics, stricture characteristics, urethroplasty technique, and outcome. A successful outcome was defined as peak flow rate > 15 mls/s, a patent urethra on retrograde urethrogram, patient satisfaction with urine stream, or restoration of the normal stream of urine with only one attempt at urethral calibration or internal urethrotomy postoperatively. Data was analyzed using PASW Statistics for Windows, Version 18.0. Results: Overall, 43 urethroplasties were done over the study period in elderly men. The age range was 65 to 87 years. The commonest aetiology was catheterization (62.79%) followed by urethritis (32.56%). Stricture length ranged from 0.5 cm to 16 cm with a mean of 3.93 cm. Most patients (60.46%) had bulbar urethral strictures. The repair methods employed were anastomotic urethroplasty (62.80%), fasciocutaneous flap (FCF) ventral onlay (13.95%), buccal mucosa graft (BMG) ventral onlay urethroplasty (4.65%), and staged urethroplasty (4.65%). Three of the patients (6.98%) had a combination of anastomotic and tissue transfer urethroplasty. The overall success rate was 88.37%. Complications included three surgical site infections, two urethral diverticula and one glans dehiscence. Conclusion: Elderly men tolerate urethroplasty well and the procedure should not be denied solely based on age.

An interacting multiple model-based two-stage Kalman filter for vehicle positioning

To address the problem that a general augmented state Kalman filter or a two-stage Kalman filter cannot achieve satisfactory positioning performance when facing uncertain noise of the micro-electro-mechanical system（MEMS） inertial sensors, a novel interacting multiple model-based two-stage Kalman filter（IMM-TSKF） is proposed to adapt to the uncertain inertial sensor noise. Three bias filters are developed based on different noise characteristics to cover a wide range of noise levels. Then, an accurate estimation of biases is calculated by the interacting multiple model algorithm to correct the bias-free filter. Thus, the vehicle positioning system can achieve good performance when suffering from uncertain inertial sensor noise. The experimental results indicate that the average position error of the proposed IMMTSKF is 25% lower than that of the general TSKF.

Production of Light Olefins from Biosyngas by Two-stage Catalytic Conversion Process via Dimethyl Ether

NiSAPO-34 and NiSAPO-34/HZSM-5 were prepared and evaluated for the performance of dimethyl ether （DME） conversion to light olefins （DTO）. The processes of two-stage light olefin production, DME synthesis and the following DTO, were also investigated using biosyngas as feed gas over Cu/Zn/A1/HZSM-5 and the optimized 2%NiSAPO-34/HZSM- 5. The results indicated that adding 2%Ni to SAPO-34 did not change its topology structure, but resulted in the forming of the moderately strong acidity with decreasing acid amounts, which slightly enhanced DME conversion activity and C2=-C3= selectiw ity. Mechanically mixing 2%NiSAPO-34 with HZSM-5 at the weight ratio of 3.0 further prolonged DME conversion activity to be more than 3 h, which was due to the stable acid sites from HZSM-5. The highest selectivity to light olefins of 90.8% was achieved at 2 h time on stream. The application of the optimized 2%NiSAPO-34/HZSM-5 in the second-stage reactor for DTO reaction showed that the catalytic activity was steady for more than 5 h and light olefin yield was as high as 84.6 g/m3syngas when the biosyngas （H2/CO/CO2/N2/CH4=41.5/26.9/14.2/14.6/2.89, vol%） with low H/C ratio of 1.0 was used as feed gas.

基于Two-stage DEA-Tobit模型的中国省际竞技体育效率研究

基于Two-stage DEA的网络结构DEA方法,对我国31个省(直辖市、自治区)在第十二届全运会上的表现进行更深入的效率评价,并结合Tobit回归模型对影响竞技体育效率的社会环境因素进行分析.结果表明,全运会两个阶段中,仅山东省和西藏自治区为DEA有效的,AP阶段和AC阶段为DEA有效的地区分别为10个和3个,且提高各地区总效率的关键在于提高其AC阶段效率.从影响因素来看,地区经济水平与效率间存在负向影响,而体育场地资源配置及体育类支出是影响效率的主要因素,国民体质综合指数和体育投入规模对其无显著影响.

Advanced landfill leachate treatment using a two-stage UASB-SBR system at low temperature

A two-stage upflow anaerobic sludge blanket （UASB） and sequencing batch reactor （SBR） system was introduced to treat landfill leachate for advanced removal of COD and nitrogen at low temperature. In order to improve the total nitrogen （TN） removal efficiency and to reduce the COD requirement for denitrification, the raw leachate with recycled SBR nitrification supematant was pumped into the first-stage UASB （UASB1） to achieve simultaneous denitrification and methanogenesis. The results showed that UASB1 played an important role in COD removal and UASB2 and SBR further enhanced the nutrient removal efficiency. When the organic loading rates of UASB1, UASB2 and SBR were 11.95, 1.63 and 1.29 kg COD/（m^3.day）, respectively, the total COD removal efficiency of the whole system reached 96.7%. The SBR acted as the real undertaker for NH4^＋-N removal due to aerobic nitrification. The system obtained about 99.7% of NH4^＋-N removal efficiency at relatively low temperature （14.9-10.9℃）. More than 98.3% TN was removed through complete denitrification in UASB 1 and SBR. In addition, temperature had a significant effect on the rates of nitrification and denitrification rather than the removal of TN and NH4^＋-N once the complete nitrification and denitrification were achieved.

Multi-objective optimization for leaching process using improved two-stage guide PSO algorithm

A mathematical mechanism model was proposed for the description and analysis of the heat-stirring-acid leaching process.The model is proved to be effective by experiment.Afterwards,the leaching problem was formulated as a constrained multi-objective optimization problem based on the mechanism model.A two-stage guide multi-objective particle swarm optimization(TSG-MOPSO) algorithm was proposed to solve this optimization problem,which can accelerate the convergence and guarantee the diversity of pareto-optimal front set as well.Computational experiment was conducted to compare the solution by the proposed algorithm with SIGMA-MOPSO by solving the model and with the manual solution in practice.The results indicate that the proposed algorithm shows better performance than SIGMA-MOPSO,and can improve the current manual solutions significantly.The improvements of production time and economic benefit compared with manual solutions are 10.5% and 7.3%,respectively.