Primary duct closure versus T-tube drainage after laparoscopic common bile duct exploration:a meta-analysis

Background and aims:Laparoscopic common bile duct exploration(LCBDE)is considered a safe and effective method for the removal of bile duct stones.However,the choice of primary duct closure(PDC)or T-tube drainage(TTD)technique after LCBDE is still controversial.This study aimed to compare the safety and effectiveness of PDC and TTD after LCBDE.Methods:Studies published before May 1,2021 in Pub Med,Web of Science,and Cochrane Library databases were searched to screen out randomized controlled trials(RCTs)and cohort studies to compare PDC with TTD.Meta-analyses of fixed effect and random effect models were performed using Rev Man 5.3.Results:A total of 1865 patients were enrolled in six RCTs and ten cohort studies.Regarding RCTs,the PDC group was significantly better than the TTD group in terms of operation time,total postoperative complications,postoperative hospital stay,and hospitalization expenses(all P<0.05).Based on cohort studies of the subgroup,the PDC group had shorter operation time,shorter postoperative hospital stay,less intraoperative blood loss,and limited total postoperative complications.Statistically,there were no significant differences in bile leakage,retained stones,stone recurrence,bile duct stricture,postoperative pancreatitis,other complications,or postoperative exhaust time between the TTD and PDC groups.Conclusions:Based on the available evidence,compared with TTD,PDC is safe and effective,and can be used as the first choice after transductal LCBDE in patients with choledocholithiasis.

Semi-analytical solution for drained expansion analysis of a hollow cylinder of critical state soils

The expansion of a thick-walled hollow cylinder in soil is of non-self-similar nature that the stress/deformation paths are not the same for different soil material points.As a result,this problem cannot be solved by the common self-similar-based similarity techniques.This paper proposes a novel,exact solution for rigorous drained expansion analysis of a hollow cylinder of critical state soils.Considering stress-dependent elastic moduli of soils,new analytical stress and displacement solutions for the nonself-similar problem are developed taking the small strain assumption in the elastic zone.In the plastic zone,the cavity expansion response is formulated into a set of first-order partial differential equations(PDEs)with the combination use of Eulerian and Lagrangian descriptions,and a novel solution algorithm is developed to efficiently solve this complex boundary value problem.The solution is presented in a general form and thus can be useful for a wide range of soils.With the new solution,the non-self-similar nature induced by the finite outer boundary is clearly demonstrated and highlighted,which is found to be greatly different to the behaviour of cavity expansion in infinite soil mass.The present solution may serve as a benchmark for verifying the performance of advanced numerical techniques with critical state soil models and be used to capture the finite boundary effect for pressuremeter tests in small-sized calibration chambers.

Palliative long-term abdominal drains vs large volume paracenteses for the management of refractory ascites in end-stage liver disease

BACKGROUND Long-term abdominal drains(LTAD)are a cost-effective palliative measure to manage malignant ascites in the community,but their use in patients with end-stage chronic liver disease and refractory ascites is not routine practice.The safety and cost-effectiveness of LTAD are currently being studied in this setting,with preliminary positive results.We hypothesised that palliative LTAD are as effective and safe as repeat palliative large volume paracentesis(LVP)in patients with cirrhosis and refractory ascites and may offer advantages in patients’quality of life.AIM To compare the effectiveness and safety of palliative LTAD and LVP in refractory ascites secondary to end-stage chronic liver disease.METHODS A retrospective,observational cohort study comparing the effectiveness and safety outcomes of palliative LTAD and regular palliative LVP as a treatment for refractory ascites in consecutive patients with end-stage chronic liver disease followed-up at our United Kingdom tertiary centre between 2018 and 2022 was conducted.Fisher’s exact tests and the Mann-Whitney U test were used to compare qualitative and quantitative variables,respectively.Kaplan-Meier survival estimates were generated to stratify time-related outcomes according to the type of drain.RESULTS Thirty patients had a total of 35 indwelling abdominal drains and nineteen patients underwent regular LVP.The baseline characteristics were similar between the groups.Prophylactic antibiotics were more frequently prescribed in patients with LTAD(P=0.012),while the incidence of peritonitis did not differ between the two groups(P=0.46).The incidence of acute kidney injury(P=0.014)and ascites/drain-related hospital admissions(P=0.004)were significantly higher in the LVP group.The overall survival was similar in the two groups(log-rank P=0.26),but the endpoint-free survival was significantly shorter in the LVP group(P=0.003,P<0.001,P=0.018 for first ascites/drain-related admission,acute kidney injury and drain-related complications,respectively).CONCLUSION The use of LTAD in the management of refractory ascites in palliated end-stage liver disease is effective,safe,and may reduce hospital admissions and utilisation of healthcare resources compared to LVP.

Modelling smear effect of vertical drains using a diameter reduction method

Vertical drains are used to accelerate consolidation of clays in ground improvement projects.Smear zones exist around these drains,where permeability is reduced due to soil disturbance caused by the installation process.Hansbo solution is widely used in practice to consider the effects of drain discharge capacity and smear on the consolidation process.In this study,a computationally efficient diameter reduction method(DRM)obtained from the Hansbo solution is proposed to consider the smear effect without the need to model the smear zone physically.Validated by analytical and numerical results,a diameter reduction factor is analytically derived to reduce the diameter of the drain,while achieving similar solutions of pore pressure dissipation profile as the classical full model of the smear zone and drain.With the DRM,the excess pore pressure u obtained from the reduced drain in the original un-disturbed soil zone is accurate enough for practical applications in numerical models.Such performance of DRM is independent of soil material property.Results also show equally accurate performance of DRM under conditions of multi-layered soils and coupled radial-vertical groundwater flow.

Special stent for draining the abdominal abscess respectively from colon and duodenum:A case report

BACKGROUND Postoperative abdominal infections are an important and heterogeneous health challenge.Many samll abdominal abscesses are resolved with antibiotics,but larger or symptomatic abscesses may require procedural management.CASE SUMMARY A 65-year-old male patient who suffered operation for the left hepatocellular carcinoma eight months ago,came to our hospital with recurrent abdominal pain,vomit,and fever for one month.Abdominal computed tomography showed that a big low-density dumbbell-shaped mass among the liver and intestine.Colonoscopy showed a submucosal mass with a fistula at colon of liver region.Gastroscopy showed a big rupture on the submucosal mass at the descending duodenum and a fistula at the duodenal bulb.Under colonoscopy,the brown liquid and pus were drained from the mass with“special stent device”.Under gastroscopy,we closed the rupture of the mass with a loop and six clips for purse stitching at the descending duodenum,and the same method as colonoscopy was used to drain the brown liquid and pus from the mass.The symptom of abdominal pain,vomit and fever were relieved after the treatment.CONCLUSION The special stent device could be effectively for draining the abdominal abscess respectively from colon and duodenum.

Study of the Efficiency of Vertical Drains by an FEM Method in Soil Treatment for Road Projects: Case of the Development and Bitumination Works of the ROCADE Porto-Novo in Benin

This article aims to study the efficiency of coupled vertical drains for the treatment of long-lasting compressible clay soils for the road project platform of the ring road of Porto Novo, capital of Benin. The experimental data allowed us to estimate a consolidation of 29% in 9 months, justifying the drainage of the soil. In order to study the efficiency of drainage, a FEM model was proposed simulating different scenarios. These include a drainless road, pavements equipped with vertical drains with meshes of 0.5 m 0.5 m, 1 m 1 m and 1.5 m 1.5 m respectively and horizontal drains. The results expressed in terms of variations in vertical stresses, effective stresses and shear deformations revealed significant variations in pavement performance depending on the mesh size of the vertical drains. The configuration with a mesh of 0.5 m 0.5 m showed the least deformations, thus indicating a reduction in deformations and better stress distribution. However, the other mesh configurations showed variable results, underlining the importance of choosing the right mesh for the specific project conditions.

基于Drain3与Loganomaly的网络安全日志分析与事件响应

随着信息技术的发展,网络安全问题日益凸显,为了保障网络系统的稳定运行,对HDFS-v1日志进行研究。首先,利用Drain3算法对日志进行解析,有效避免了构造深度较大、不平衡的树,实验结果显示其精确率、召回率、F1度量及准确度均高达100%;其次,基于Loganomaly算法进行异常检测,训练结果训练集、验证集损失值分别为0.21、0.18,预测结果精确度为96.889%,召回率为93.604%,F1度量为95.218%;接着,再用Drain3算法对异常日志分类;最后,通过远程控制实现异常事件响应,发送报警邮件,确保在HDFS发生紧急情况时能够快速、有效地处理故障,保障大数据处理任务的稳定进行。

Coupling Aquaculture—Crop Productions and Using of Water Drained from Ponds Rearing Clarias gariepinus as Fertilizer for Okra Production (Abelmoschus esculentus var. Clemson spineless, L. Moench)

The present study concerns the revalorization of drained water from aquaculture ponds rearing Clarias gariepinus on okra crops. The rearing was carried out at the farm of Gaston Berger University in 100 m2 ponds. In each pond, the individuals of C. garipinus with an average weight of 6 ± 0.3 g were stocked at a density of 11 per m2. The water temperature and pH were measured during the experiment. The control fishing is carried out every month to monitor variations in the weight and size of reared individuals. The plant production is carried out in elementary plots measuring 3 m × 1.5 m. Each plot was fertilized with either: drained water from C. gariepinus rearing (DWC), poultry droppings (PD), cow dung (CD) and mineral fertilizer (NPK). Treatments are carried out in tripliqua with either river water (RW), RW + the recommended dose of NPK (RD-NPK), RW + RD-PD, RW + RD-CD, DWC, DWC + 25% RD-NPK, DWC + 50% RD-NPK, DWC + 75% RD-NPK, DWC + 25% RD-PD, DWC + 50% RD-PD, DWC + 75% RD-PD, DWC + 25% RD-CD, DWC + 50% RD-CD, DWC + 75% RD-CD. Growth parameters and yield of okra were determined. The average temperature in the rearing environment was 27.6 ± 1.5˚C and pH 7.9 ± 1.1. After six (06) months of rearing, C. gariepinus individuals reached an average weight of 850.12 ± 1.3 g and an average height of 52.44 ± 1.1 cm. The daily weight gain and specific growth rates over this period were 3.9 g per day and 2.8% per day, respectively. The treatment T1 (RW + DR-NPK) gave the highest mean collar diameter and mean plant height with 2.3 ± 0.9 cm and 61.6 ± 32 cm, respectively. In T4 (DWC), the mean height of plants was 38.8 ± 23.5 cm and mean collar diameter 1.4 ± 0.8 cm. The growth performance in T4 was comparable to that of RD-CD (T3), but different from RD-NPK (T1) and RD-PD (T2). The highest average number, average weight, average length and average diameter of fruits were noted in treatments T13 (RW + RD-75%CD) and T7 (DWC + 75% RD-NPK). The best yields were noted in T1 (RW + RD-NPK) = 10.8 ± 5.4 t·ha−1, T5 (DWC + 25% RD-NPK) = 9.2 ± 4.6 t·ha−1 and T4 (DWC) = 8.6 ± 4.3 t·ha−1 which are comparable and higher than those obtained in T2 = 5.7 ± 2.8 t·ha−1 and T3 = 7.5 ± 3.8 t·ha−1.

基于“T-tube”模型的中心动脉脉搏波双通道盲辨识

提出了由两路人体外周动脉脉搏波(peripheral artery pulse wave,PAP)来估计中心动脉脉搏波(central aortic pulse wave,CAP)的多通道盲辨识(multi-channel blind system identification,MBSI)方法,旨在实现心血管系统中心动脉脉搏波的实时无创连续监测.首先简单介绍了多通路盲辨识算法,并证明了心血管系统IIR模型特性可由FIR模型逼近,从而简化了MBSI算法.然后介绍了心血管"T-tube"模型,并结合两路外周动脉实测(肱动脉、股动脉)脉搏波来重建中心动脉脉搏波和辨识模型.结果表明,MBSI算法稳定性较好,估计出的CAP波形畸变率百分比小于6%、形态整体能量误差百分比小于3%.

隧道涌水量基于MODFLOW中DRAIN模块水力传导系数取值探析

目前Visual Modflow已广泛地应用于隧道涌水的模拟,Drain模块中的水力传导系数是一个综合系数,但没有可参考的取值范围。从排水沟水力传导系数对隧洞涌水量引起的变化入手,通过C值的不同取值范围,利用模型计算出的涌水量与真实涌水量进行对比,发现当水力传导系数取值在一定范围内时计算出的涌水量最接近施工时隧道的真实涌水量,以此为Drain模块中水力传导系数的取值作一个经验参考。

新型Drain Box设计与应用

本文首先介绍了目前国内海上油气田设施开排系统设计的工艺设计流程的原理及应用特点,随后通过对比分析介绍了一种新型DrainBox的设计与运用,最后对该新型DrainBox的创新点进行了分析和介绍,并对其推广与应用前景进行了展望。

Prophylactic intra-peritoneal drain placement following pancreaticoduodenectomy:A systematic review and metaanalysis

AIM:To conduct a meta-analysis comparing outcomes after pancreaticoduodenectomy(PD)with or without prophylactic drainage.METHODS:Relevant comparative randomized and nonrandomized studies were systemically searched based on specific inclusion and exclusion criteria.Postoperative outcomes were compared between patients with and those without routine drainage.Pooled odds ratios(OR)with 95%CI were calculated using either fixed effects or random effects models.RESULTS:One randomized controlled trial and four non-randomized comparative studies recruiting 1728patients were analyzed.Patients without prophylactic drainage after PD had significantly higher mortality(OR=2.32,95%CI:1.11-4.85;P=0.02),despite the fact that they were associated with fewer overall complications(OR=0.62,95%CI:0.48-0.82;P=0.00),major complications(OR=0.75,95%CI:0.60-0.93;P=0.01)and readmissions(OR=0.77,95%CI:0.60-0.98;P=0.04).There were no significant differences in the rates of pancreatic fistula,intraabdominal abscesses,postpancreatectomy hemorrhage,biliary fistula,delayed gastric emptying,reoperation or radiologic-guided drains between the two groups.CONCLUSION:Indiscriminate abandonment of intraabdominal drainage following PD is associated with greater mortality,but lower complication rates.Future randomized trials should compare routine vs selective drainage.

A new concept of backfll design—Application of wick drains in backflled stopes

Backflling represents an environmentally friendly mining waste disposal technique.It is increasingly used in underground mines all over the world.However,its primary purpose remains to improve ground stability and to reduce ore dilution.Previous investigations have shown that fll drainage plays a key role in backfll and barricade design.With a poor drainage system in the backflled stope,the required dimension of barricade,which is constructed at the base of the stope near the drift entrance,has to be increased.A poor backfll drainage system can also lead to a signifcant increase in drainage waiting time and further reduction in mining productivity.In this paper,the drainage of conventional backfll design in backflled stopes is briefly reviewed.For the frst time,the application of the wick drain is introduced in the backfll within mine stopes.The drainage improvement from the introduction of the wick drain is illustrated using numerical modeling.

FREEZE PROFILE AND HEAT BALANCE CALCULATION OF THE 160kA DRAINED CELL

A 2D full cell thermo-electric model of 160kA drained cell was set up using finiteelement code to calculate its freeze profile, then the drained cell model was modifiedaccording to the freeze profile computed and its heat balance was calculated. Comparedwith that of a 160kA conventional Hall-Heroult cell (H-H cell), though the melts vol-ume of the drained cell reduced greatly, the whole heat loss from it didn't drop downapparently, and an analysis was presented in the paper. On the other hand, the anode-cathode distance (ACD) of a drained cell was much less than that of a H-H cell, sothe voltage drop on it and heat produced decreased too, steps should be taken to keepa workable heat balance on a drained cell.

Drainage by urostomy bag after blockage of abdominal drain in patients with cirrhosis undergoing hepatectomy

Abdominal drainage was previously recommended as a post-hepatectomy procedure for patients with cirrhosis.This report introduces a simple technique that prevents leakage of ascitic fluid after cirrhotic hepatectomy complicated by blockage of the abdominal drain.In 59 patients who had had cirrhotic hepatectomy complicated by leakage of ascites in the drain site after drainage removal between January 2001 and April 2011,31 underwent suture ligation(sutured group) and 28 were given urostomy bag at the abdominal drainage site(drainage group).The mean length of postoperative hospital stay in the drainage group was shorter than in the sutured group(16.11±2.61 vs 34.23±4.86 days,P=0.000).Meanwhile,the drainage group showed decreased postoperative complications,including leakage of ascites,wound infection,and collection of ascites.Drainage by urostomy bag can prevent prolonged leakage of ascitic fluid after the blockage of abdominal drains in patients undergoing cirrhotic hepatectomy.

Diagnostic value of drain amylase for detecting intrathoracic leakage after esophagectomy

AIM:To investigate the value of elevated drain amylase concentrations for detecting anastomotic leakage(AL) after minimally invasive Ivor-Lewis esophagectomy(MIILE).METHODS:This was a retrospective analysis of prospectively collected data in two hospitals in the Netherlands. Consecutive patients undergoing MI-ILE were included. A Jackson-Pratt drain next to the dorsal side of the anastomosis and bilateral chest drains were placed at the end of the thoracoscopic procedure. Amylase levels in drain fluid were determined in all patients during at least the first four postoperative days. Contrast computed tomography scans and/or endoscopic imaging were performed in cases of a clinically suspected AL. Anastomotic leakage was defined as any sign of leakage of the esophago-gastric anastomosis on endoscopy,re-operation,radiographic investigations,post mortal examination or when gastro-intestinal contents were found in drain fluid. Receiver operator characteristic curves were used to determine the cut-off values. Sensitivity,specificity,positive predictive value,negative predictive value,risk ratio and overall test accuracy were calculated for elevated drain amylase concentrations.RESULTS:A t o t a l o f 8 9 p a t ie n t s w e re in c lu d e d between March 2013 and August 2014. No differences in group characteristics were observed between patients with and without AL,except for age. Patients with AL were older than were patients without AL(P = 0.01). One patient(1.1%) without AL died within 30 d after surgery due to pneumonia and acute respiratory distress syndrome. Anastomotic leakage that required any intervention occurred in 15 patients(16.9%). Patients with proven anastomotic leakage had higher drain amylase levels than patients without anastomotic leakage [median 384 IU/L(IQR 34-6263) vs median 37 IU/L(IQR 26-66),P = 0.003]. Optimal cut-off values on postoperative days 1,2,and 3 were 350 IU/L,200 IU/L and 160 IU/L,respectively. An elevated amylase level was found in 9 of the 15 patients with AL. Five of these 9 patients had early elevations of their amylase levels,with a median of 2 d(IQR 2-5) before signs and symptoms occurred.CONCLUSION:Measurement of drain amylase levels is an inexpensive and easy tool that may be used to screen for anastomotic leakage soon after MI-ILE. However,clinical validation of this marker is necessary.

A CAD oriented quasi-analytical large-signal drain current model for 4H-SiC MESFETs

This paper reports that a 4H-SiC MESFET （Metal Semiconductor Field Effect Transistor） large signal drain current model based on physical expressions has been developed to be used in CAD tools. The form of drain current model is based on semi-empirical MESFET model, and all parameters in this model are determined by physical parameters of 4H-SiC MESFET. The verification of the present model embedded in CAD tools is made, which shows a good agreement with measured data of large signal DC I-V characteristics, PAE （power added efficiency）, output power and gain.

Role of equal-strain assumption in unit-cell theory for consolidation with vertical drains

In the development of unit-cell theory for the analytical analysis of consolidation with vertical drains, the equal-strain assumption is often made with the intention of modelling consolidation under uniform settlement conditions. In contrast, the free-strain assumption for modelling consolidation under uniform load conditions is seldom employed, mainly because of the complexities involved in the analysis. This study derives a rigorous analytical solution to the generalised governing equations of free-strain consolidation with a vertical drain subjected to an instantaneous load. Calculated results from the newly proposed solution are compared with those from three available solutions derived based on the equal-strain assumption. Surprisingly good agreement is obtained in terms of excess pore-water pressure, degree of consolidation, and settlement. Horizontal profiles of settlement were not uniform before the end of consolidation. This indicates that the uniform settlement condition is not actually reproduced by the analytical solutions derived based on the equal-strain assumption. The equal-strain assumption is a sufficient but not necessary condition for deriving an analytical solution to unit-cell consolidation theory. The assumption plays no role in modelling consolidation under uniform settlement conditions but simplifies the analytical analysis of free-strain consolidation and results in an approximate solution of high accuracy for consolidation under uniform load conditions. Moreover, drain resistance and smear effects not only retard the consolidation rate, but also importantly shape the vertical and horizontal profiles of excess pore-water pressure, respectively.

Visualization of drained rock volume(DRV) in hydraulically fractured reservoirs with and without natural fractures using complex analysis methods(CAMs)

The drainage areas(and volumes)near hydraulically fractured wells,computed and visualized in our study at high resolution,may be critically affected by the presence of natural fractures.Using a recently developed algorithm based on complex analysis methods(CAMs),the drained rock volume(DRV)is visualized for a range of synthetic constellations of natural fractures near hydraulic fractures.First,flow interference effects near a single hydraulic fracture are systematically investigated for a variety of natural fracture sets.The permeability contrast between the matrix and the natural fractures is increased stepwise in order to better understand the effect on the DRV.Next,a larger-scale model investigates flow interference for a full hydraulically fractured well with a variety of natural fracture sets.The time of flight contours(TOFCs)outlining the DRV are for all cases with natural fractures compared to a base case without any natural fractures.Discrete natural fractures,with different orientations,hydraulic conductivity,and fracture density,may shift the TOFC patterns in the reservoir region drained by the hydraulically fractured well,essentially shifting the location of the well’s drainage area.The CAM-based models provide a computationally efficient method to quantify and visualize the drainage in both naturally and hydraulically fractured reservoirs.

Biliary leaks after laparoscopic cholecystectomy:time to stent or time to drain

BACKGROUND:Endoscopic retrograde cholangiopan- creatography(ERCP)with placement of a biliary stent or nasobiliary(NB)drain is the procedure of choice for treatment of post-cholecystectomy bile duct leaks.The aim of this study was to compare the effect of NB drainage versus internal biliary stenting on rates of leak closure, time elapsed until drain or stent removal,length of hospital stay and number of required endoscopic procedures. METHODS:Charts were reviewed on 20 patients who underwent laparoscopic cholecystectomy complicated by Luschka or cystic duct leak.Ten patients were treated with NB drains connected to low intermittent suction and repeat NB cholangiograms were performed until leak closure was observed.Ten patients were treated with internal biliary stents.Biliary sphincterotomies were performed for stone extraction or a presumed papillary stenosis.Large bilomas were drained percutaneously prior to stenting. RESULTS:In all 20 patients,a cholangiogram and successful placement of a NB drain or internal stent was achieved.Four patients(20%)were found to have bile duct stones,which were extracted following a sphincterotomy. Sixteen patients required percutaneous drains to evacuate large bilomas prior to biliary instrumentation.Fifteen cystic duct leaks and 5 Luschka duct leaks were reviewed. There were no complications related to ERCP.Closure of the leak was documented within 2 to 11 days(mean 4.7±0.9 days)in patients receiving a NB drain.The drains were removed non-endoscopically following leak closure. The internal stent group required stenting for 14 to 53 days(mean 29.1±4.4 days).The stent was then removed endoscopically after documentation of leak closure.Bile leaks following laparoscopic cholecystectomy closed rapidly after NB drainage and did not require repeat endoscopy for removal of the NB drain,resulting in fewer ERCPs required for treatment of biliary leaks.Internal biliary stents were in place longer owing to the nature of this intermittent endoscopic approach but an accurate comparison of time to leak closure could not be determined. Leak closure resulted once the bile flow was re-established, regardless of the technique,but removal of the NB drains was performed earlier than removal of the biliary stents. The number of ERCPs required per patient was 1.0±0 in the NB group and 2.2±0.1(range 2-3)in the internal stent group.The length of hospitalization was 8.7±3.3 days for the NB group and 7.5±2.3 days for the internal stent group.Biliary stent placement resulted in an insignificant decrease in hospitalization at the expense of generating twice as many endoscopic procedures. CONCLUSIONS:Our data suggest that NB drainage may be advantageous in patients requiring a prolonged hospital admission or in patients in whom repeat endoscopy is undesirable.Internal biliary stenting appears preferable when early discharge is anticipated or when expertise in placement and management of NB drains is lacking.