Endoscopic retrograde cholangiopancreatography,endoscopic papillary balloon dilation,and laparoscopic hepatectomy for intraand extrahepatic bile duct stones

BACKGROUND Intrahepatic and extrahepatic bile duct stones(BDSs)have a high rate of residual stones,a high risk of recurrence,and a high rate of reoperation.It is very important to take timely and effective surgical intervention for patients.AIM To analyze the efficacy,postoperative rehabilitation,and quality of life(QoL)of patients with intra-and extrahepatic BDSs treated with endoscopic retrograde cholangiopancreatography(ERCP)+endoscopic papillary balloon dilation(EPBD)+laparoscopic hepatectomy(LH).METHODS This study selected 114 cases of intra-and extrahepatic BDSs from April 2021 to April 2024,consisting of 55 cases in the control group receiving laparoscopic common bile duct exploration and LH and 59 cases in the observation group treated with ERCP+EPBD+LH.Efficacy,surgical indicators[operation time(OT)and intraoperative blood loss(IBL)],postoperative rehabilitation(time for body temperature to return to normal,time for pain relief,and time for drainage to reduce jaundice),hospital stay,medical expenses,and QoL[Gastrointestinal Quality of Life Index(GIQLI)]were comparatively analyzed.Further,Logistic regression analysis was conducted to analyze factors influencing the QoL of patients with intra-and extrahepatic BDSs.RESULTS The data demonstrated a higher overall effective rate in the observation group compared to the control group(P=0.011),together with notably reduced OT,less IBL,shorter body temperature recovery time,pain relief time,time for drainage to reduce jaundice,and hospital stay(all P<0.05).The postoperative GIQLI of the observation group was more significantly increased compared to the control group(P<0.05).The two groups demonstrated no marked difference in medical expenses(P>0.05).CONCLUSION The above indicates that ERCP+EPBD+LH is effective in treating patients with intra-and extrahepatic BDSs,which is conducive to postoperative rehabilitation and QoL improvement,with promising prospects for clinical promotion.

A Sort of Gray-scale Morphological Dilations and Erosions

We introduce first a sort of gray-scale morphological dilations and erosions, which might have some further applications in image analysis. Then we show that the dilation and the erosion defined here form adjunctive pairs. The duality between the dilation and the erosion and some other properties, such as homothety, of these operators are discussed the Commuting property with translation and as well.

Erosion control of Chinese loess using polymer SH and ryegrass

The China Loess Plateau is subjected to severe soil erosion triggered by intense rainfall,resulting in significant harm and losses to both human society and the natural surroundings.In this study,a novel technique for managing loess erosion is introduced,which involves the utilization of a combined polymer SH and ryegrass.A comprehensive series of tests were undertaken,including rainfall erosion tests,disintegration experiments,and scanning electron microscopy examinations,to assess the accumulative sediment yield(ASY),disintegration ratio,and microstructural features of both untreated and treated loess samples.The results showed a significant reduction in ASY with increased dry density of untreated loess.Furthermore,the combined technique effectively controlled erosion,limiting ASY to 266.2 g/cm^(2)in 60 minutes.This was approximately one-sixth,one-ninth,and one-fifteenth of the ASY in SH-treated loess(L-SH),ryegrass-treated loess(L-R),and untreated loess,respectively.It resisted disintegration better than ryegrass alone but slightly less than SH.This improvement was due to the combined effect of SH and ryegrass,which reduced raindrop impact,improved loess microstructure,and boosted ryegrass growth.The innovative technique holds the potential to be applied as a field-scale technique in the Loess Plateau region of China.

Research on the solid particle erosion wear of pipe steel for hydraulic fracturing based on experiments and numerical simulations

Erosion wear is a common failure mode in the oil and gas industry.In the hydraulic fracturing,the fracturing pipes are not only in high-pressure working environment,but also suffer from the impact of the high-speed solid particles in the fracturing fluid.Beneath such complex conditions,the vulnerable components of the pipe system are prone to perforation or even burst accidents,which has become one of the most serious risks at the fracturing site.Unfortunately,it is not yet fully understood the erosion mechanism of pipe steel for hydraulic fracturing.Therefore,this article provides a detailed analysis of the erosion behavior of fracturing pipes under complex working conditions based on experiments and numerical simulations.Firstly,we conducted erosion experiments on AISI 4135 steel for fracturing pipes to investigate the erosion characteristics of the material.The effects of impact angle,flow velocity and applied stress on erosion wear were comprehensively considered.Then a particle impact dynamic model of erosion wear was developed based on the experimental parameters,and the evolution process of particle erosion under different impact angles,impact velocities and applied stress was analyzed.By combining the erosion characteristics,the micro-structure of the eroded area,and the micro-mechanics of erosion damage,the erosion mechanism of pipe steel under fracturing conditions was studied in detail for the first time.Under high-pressure operating conditions,it was demonstrated through experiments and numerical simulations that the size of the micro-defects in the eroded area increased as the applied stress increased,resulting in more severe erosion wear of fracturing pipes.

Failure transition of shear-to-dilation band of rock salt under triaxial stresses

Great potential of underground gas/energy storage in salt caverns seems to be a promising solution to support renewable energy.In the underground storage method,the operating cycle unfortunately may reach up to daily or even hourly,which generates complicated pressures on the salt cavern.Furthermore,the mechanical behavior of rock salt may change and present distinct failure characteristics under different stress states,which affects the performance of salt cavern during the time period of full service.To reproduce a similar loading condition on the cavern surrounding rock mass,the cyclic triaxial loading/unloading tests are performed on the rock salt to explore the mechanical transition behavior and failure characteristics under different confinement.Experimental results show that the rock salt samples pre-sent a diffused shear failure band with significant bulges at certain locations in low confining pressure conditions(e.g.5 MPa,10 MPa and 15 MPa),which is closely related to crystal misorientation and grain boundary sliding.Under the elevated confinement(e.g.20 MPa,30 MPa and 40 MPa),the dilation band dominates the failure mechanism,where the large-size halite crystals are crushed to be smaller size and new pores are developing.The failure transition mechanism revealed in the paper provides additional insight into the mechanical performance of salt caverns influenced by complicated stress states.

Experimental and numerical simulation study on the erosion behavior of the elbow of gathering pipeline in shale gas field

During the production period of shale gas, proppant particles and rock debris are produced together,which will seriously erode the elbows of gathering pipelines. In response to this problem, this paper takes the elbow of the gathering pipeline in the Changning Shale Gas Field as an example to test the erosion rate and material removal mechanism of the test piece at different angles of the elbow through experiments and compares the four erosion models with the experimental results. Through analysis, it is found that the best prediction model for quartz sand-carbon steel erosion is the Oka model. Based on the Oka model, FLUENT software was used to simulate and analyze the law of erosion of the elbow of the gas gathering pipeline under different gas flow velocities, gas gathering pressure, particle size, length of L1,and bending directions of the elbow. And a spiral pipeline structure is proposed to reduce the erosion rate of the elbow under the same working conditions. The results show that this structure can reduce erosion by 34%.

Assessment of soil erosion in the Irga watershed on the eastern edge of the Chota Nagpur Plateau,India

Human activities to improve the quality of life have accelerated the natural rate of soil erosion.In turn,these natural disasters have taken a great impact on humans.Human activities,particularly the conversion of vegetated land into agricultural land and built-up area,stand out as primary contributors to soil erosion.The present study investigated the risk of soil erosion in the Irga watershed located on the eastern fringe of the Chota Nagpur Plateau in Jharkhand,India,which is dominated by sandy loam and sandy clay loam soil with low soil organic carbon(SOC)content.The study used the Revised Universal Soil Loss Equation(RUSLE)and Geographical Information System(GIS)technique to determine the rate of soil erosion.The five parameters(rainfall-runoff erosivity(R)factor,soil erodibility(K)factor,slope length and steepness(LS)factor,cover-management(C)factor,and support practice(P)factor)of the RUSLE were applied to present a more accurate distribution characteristic of soil erosion in the Irga watershed.The result shows that the R factor is positively correlated with rainfall and follows the same distribution pattern as the rainfall.The K factor values in the northern part of the study area are relatively low,while they are relatively high in the southern part.The mean value of the LS factor is 2.74,which is low due to the flat terrain of the Irga watershed.There is a negative linear correlation between Normalized Difference Vegetation Index(NDVI)and the C factor,and the high values of the C factor are observed in places with low NDVI.The mean value of the P factor is 0.210,with a range from 0.000 to 1.000.After calculating all parameters,we obtained the average soil erosion rate of 1.43 t/(hm^(2)•a),with the highest rate reaching as high as 32.71 t/(hm^(2)•a).Therefore,the study area faces a low risk of soil erosion.However,preventative measures are essential to avoid future damage to productive and constructive activities caused by soil erosion.This study also identifies the spatial distribution of soil erosion rate,which will help policy-makers to implement targeted soil erosion control measures.

Numerical simulation on sand sedimentation and erosion characteristics around HDPE sheet sand barrier under different wind angles

For the safety of railroad operations,sand barriers are utilized to mitigate wind-sand disaster effects.These disasters,characterized by multi-directional wind patterns,result in diverse angles among the barriers.In this study,using numerical simulations,we examined the behavior of High Density Polyethylene(HDPE)sheet sand barriers under different wind angles,focusing on flow field distribution,windproof efficiency,and sedimentation erosion dynamics.This study discovered that at a steady wind speed,airflow velocity varies as the angle between the airflow and the HDPE barrier changes.Specifically,a 90°angle results in the widest low-speed airflow area on the barrier’s downwind side.If the airflow is not perpendicular to the barrier,it prompts a lateral airflow movement which decreases as the angle expands.The windproof efficiency correlates directly with this angle but inversely with the wind’s speed.Notably,with a wind angle of 90°,wind speed drops by 81%.The minimum wind speed is found at 5.1H(the sand barrier height)on the barrier’s downwind side.As the angle grows,the barrier’s windproof efficiency improves,extending its protective reach.Sedimentation is most prominent on the barrier’s downwind side,as the wind angle shifts from 30°to 90°,the sand sedimentation area on the barrier’s downwind side enlarges by 14.8H.As the angle grows,sedimentation intensifies,eventually overtakes the forward erosion and enlarges the sedimentation area.

Internal erosion characteristics and microstructure effects of undisturbed loess

Loess internal erosion caused by preferential flow often leads to serious loess ground collapse,shallow loess landslides,and other geological disasters.However,there is a lack of quantitative evaluation of the internal erodibility of undisturbed loess under the action of preferential flow,and little is known about the correlation between the internal erodibility of loess and its microstructure.In this study,we carried out a series of hole erosion tests(HET)on undisturbed loess samples from 4 typical locations on China's Loess Plateau.The internal erodibility of loess was quantitatively evaluated through an improved HET method,and its association with initial water content,clay content,and initial water head difference was investigated.On the microscopic scale,the microstructure of loess with different clay content was measured by scanning electron microscopy(SEM).The correlation between pore and particle microstructure parameters and loess internal erosion parameters was established based on grey correlation theory.When the initial water content increased from 10%to 36%,the erodibility index increased from 1 to 2.5.When the clay content increased from 8%to 27.95%,the erodibility index increased 3.5 times.The increase of initial water head difference has a positive linear effect on the internal erodibility of loess.The microstructure analysis shows that with the increase of clay content,the microstructure of undisturbed loess changes from a mosaic structure to a cementation structure,which creates favourable conditions for controlling the internal erosion of loess.Through grey correlation analysis,it has been determined that the microstructure of undisturbed loess has a significant correlation with the critical shear stress,and the loess microstructure morphology strongly correlates with the erosion rate.Under normal circumstances,the higher the clay content,the better the erosion resistance,the better the mechanical stability,and the easier to form a stable cave in loess.This study can provide a reference for revealing the cave formation mechanism in the loess area in the future.

Research on Leading Edge Erosion and Aerodynamic Characteristics of Wind Turbine Blade Airfoil

The effects of the erosion present on the leading edge of a wind turbine airfoil(DU 96-W-180)on its aerodynamic performances have been investigated numerically in the framework of a SST k–ωturbulence model based on the Reynolds Averaged Navier-Stokes equations(RANS).The results indicate that when sand-induced holes and small pits are involved as leading edge wear features,they have a minimal influence on the lift and drag coefficients of the airfoil.However,if delamination occurs in the same airfoil region,it significantly impacts the lift and resistance characteristics of the airfoil.Specifically,as the angle of attack grows,there is a significant decrease in the lift coefficient accompanied by a sharp increase in the drag coefficient.As wear intensifies,these effects gradually increase.Moreover,the leading edge wear can exacerbate flow separation near the trailing edge suction surface of the airfoil and cause forward displacement of the separation point.

Erratum to:Influence law of modified glutinous rice-based materials on gravel soil reinforcement and water erosion process

The original online version of this article was revised.The first author is“ZHANG Weng-xiang”in the original article.The first author’s name has been corrected to“ZHANG Wen-xiang”.

Trans-PRK for recurrent epithelial corneal erosion induced by cooking oil accidentally after EVO ICL

Dear Editor,We report a case with trans-photorefractive keratectomy(PRK)for recurrent epithelial corneal erosion caused by cooking oil after EVO-implantable contact lens(ICL)(EVO Visian ICL;STAAR Surgical AG,Switzerland),which should be distinguished from postoperative complications of EVO-ICL.Most corneal burns are classified as chemical and thermal burns,referring to direct contact injury to the cornea.

Long-term outcomes of urethral balloon dilation for anterior urethral stricture: A prospective cohort study

Objective:To prospectively follow up a cohort of anterior urethral stricture disease patients managed with balloon dilation(BD)for 3 years to evaluate the long-term outcomes and to study factors that contribute to recurrence.Methods:This study included men who had urethral BD for significant anterior urethral stricture disease between January 2017 and March 2019.Data about the patient age,stricture characteristics,and recurrence date were recorded,along with information on postoperative indwelling catheter use and operative complications.Furthermore,information about the self-calibration procedure was collected and where available,free flow(FF)measurements during the follow-up period were recorded and analyzed.Success was defined as a lack of symptoms and acceptable FF rates(maximum flow rate>12 mL/s).Results:The final analysis was conducted on 187 patients.The mean follow-up period was 37 months.The long-term overall success rate at the end of our study was 66.8%.Our recurrence rate was 7.4%at 12 months,24.7%at 24 months,and reached 33.2%at the end of our study.The time to recurrence ranged from 91 days to 1635 days,with a mean of 670 days.The stricture-free survival was significantly shorter with lengthy peno-bulbar(p=0.031)and multiple strictures(p=0.015),and in the group of patients who were not committed to self-calibration protocol(p<0.011).However,post-procedural self-calibration was the most important factor that may have decreased the incidence of recurrence(odds ratioZ5.85).Adjuvant self-calibration after BD not only reduced the recurrence rate from 85.4%in the non-self-calibration group to 15.1%in the self-calibration one(p<0.001),but also improved the overall stricture-free survival and FF parameters.

Solid Particle Erosion of AISI 304 SS Caused by Alumina Particles

This research work was carried out with the aim of continuing to expand knowledge on the behaviour of AISI 304 stainless steel against solid particle erosion. In this particular case, the steel was subjected to the impact of alumina particles, which are hard abrasives with irregular and angular shapes. Different characterization techniques were applied to gain a better understanding of alumina. For instance, particle size distribution was obtained using the Analysette 28 Image Sizer and the particle size was between 300 - 400 µm. SEM and EDS analysis were used to know the morphology and chemical composition of both the abrasive particles and AISI 304 stainless steel. Additionally, mechanical properties values such as the hardness and Young’s modulus of AISI 304 steel were attained using a Berkovich indenter (model TTX-NHT, CSM Instruments). On the other hand, two tests were carried out for each impact angle used, 30˚, 45˚, 60˚ and 90˚, with a particle velocity of 24 ± 2 m/s and an abrasive flow rate of 63 ± 0.5 g/min, employing a test rig based on ASTM G76-95 standard. SEM images using two detectors, Backscattered Electron Detector (BED) and Low Electron Detector (LED), were employed to identify the wear mechanisms on the AISI 304 eroded surfaces at 30˚ and 90˚. Finally, the erosion rates of AISI 304 compared to those results reached by AISI 1018 steel and AISI 420 stainless steel tested under identical conditions in previous works.

Effect of Some Physical Factors on Interrill Erosion of Soils in Gidan-Kwanu Area, Nigeria

Savanna regions in Nigeria face environmental degradation and barren land, negatively impacting food and agricultural productivity. Inter-rill erosion occurs due to raindrop impact and transport, particularly on hill slopes. A study was conducted using a sprinkler rainfall simulator and plot experiment to study soil erosion processes. Soil samples were collected from four farms in Gidan Kwanu, with varying moisture content. Sand content ranged from 46.0% to 76.20%, silt from 11.30% to 23.50%, and clay from 11.0% to 30.0%. Uncultivated and bare land had a higher average porosity (15.47% and 14.99%), while cultivated land had lower porosity (14.4%). The study found that most people in Gidan-Kwanu primarily practice farming, which is season-dependent and rain-fed. Soil type and texture significantly contribute to inter-rill erosion, with cultivated and uncultivated soil being more resistant to erosion than bare land soil. The study concluded that farming practices in Gidan-Kwanu are primarily season-dependent and rain-fed. Soil type and texture significantly contribute to inter-rill erosion, with cultivated and uncultivated soil being more resistant to erosion than bare land soil.

Soil erosion susceptibility mapping of Hangu Region,Kohat Plateau of Pakistan using GIS and RS-based models

Soil erosion is a crucial geo-environmental hazard worldwide that affects water quality and agriculture,decreases reservoir storage capacity due to sedimentation,and increases the danger of flooding and landslides.Thus,this study uses geospatial modeling to produce soil erosion susceptibility maps(SESM)for the Hangu region,Khyber Pakhtunkhwa(KPK),Pakistan.The Hangu region,located in the Kohat Plateau of KPK,Pakistan,is particularly susceptible to soil erosion due to its unique geomorphological and climatic characteristics.Moreover,the Hangu region is characterized by a combination of steep slopes,variable rainfall patterns,diverse land use,and distinct soil types,all of which contribute to the complexity and severity of soil erosion processes.These factors necessitate a detailed and region-specific study to develop effective soil conservation strategies.In this research,we detected and mapped 1013 soil erosion points and prepared 12 predisposing factors(elevation,aspect,slope,Normalized Differentiate Vegetation Index(NDVI),drainage network,curvature,Land Use Land Cover(LULC),rainfall,lithology,contour,soil texture,and road network)of soil erosion using GIS platform.Additionally,GIS-based statistical models like the weight of evidence(WOE)and frequency ratio(FR)were applied to produce the SESM for the study area.The SESM was reclassified into four classes,i.e.,low,medium,high,and very high zone.The results of WOE for SESM show that 16.39%,33.02%,29.27%,and 21.30%of areas are covered by low,medium,high,and very high zones,respectively.In contrast,the FR results revealed that 16.50%,24.33%,35.55%,and 23.59%of the areas are occupied by low,medium,high,and very high classes.Furthermore,the reliability of applied models was evaluated using the Area Under Curve(AUC)technique.The validation results utilizing the area under curve showed that the success rate curve(SRC)and predicted rate curve(PRC)for WOE are 82%and 86%,respectively,while SRC and PRC for FR are 85%and 96%,respectively.The validation results revealed that the FR model performance is better and more reliable than the WOE.

Dilation,discrimination and Uhlmann's theorem of link products of quantum channels

We establish the Stinespring dilation theorem of the link product of quantum channels in two different ways,discuss the discrimination of quantum channels,and show that the distinguishability can be improved by self-linking each quantum channel n times as n grows.We also find that the maximum value of Uhlmann's theorem can be achieved for diagonal channels.

Distribution assessment of soil erosion with revised RUSLE model in Tianshan Mountains

aSoil degradation caused by soil erosion is one of the world's most critical environmental issues.Soil erosion in the Tianshan Mountains has caused various environmental problems in the surrounding areas.This study used remote sensing data to analyze the distribution of the factors influencing soil erosion,and the revised universal soil loss equation(RUSLE)to calculate the total amount and distribution characteristics of soil erosion in the Tianshan Mountains in 2019.Due to the large error of RUSLE in soil erosion estimation in mountainous areas,this study modified RUSLE equation based on the characteristics of snow cover in the Tianshan Mountains.The results show that the average soil erosion was 1690.3 t/(km^(2)·year),of which insignificant erosion,slight erosion and moderate erosion accounted for 42,8%,22.4%and 9.9%,respectively.Severe erosion and above accounted for 13.3%.The accuracy of the soil erosion modulus calculated by the RUSLE was only 61.9%,with an average error of 1631.9 t/(km^(2)·year).The average error of the double-coefficient correction method was 1259.1 t/(km^(2)·year),and the average error of the modified formula method was reduced by 40.3%compared with the RUSLE,reaching 973.7 t/(km^(2)·year),and its accuracy reached 76.2%.Very severe erosion and catastrophic erosion are distributed on mountain ridges with higher elevation and on the northern area with higher precipitation.Snow cover has a certain inhibitory effect on soil erosion,and snow cover in alpine mountains is a factor that cannot be ignored in soil erosion research.

Effect of coir geotextile and geocell on ephemeral gully erosion in the Mollisol region of Northeast China

The unique geomorphological features and farming methods in the Mollisol region of Northeast China increase water catchment flow and aggravate the erosion of ephemeral gully(EG).Vegetation suffers from rain erosion and damage during the growth stage,which brings serious problems to the restoration of grass in the early stage.Therefore,effects of coir geotextile and geocell on EG erosion under four confluence intensities were researched in this study.Results of the simulated water discharge erosion test showed that when the confluence strength was less than 30 L/min,geocell and coir geotextile had a good effect on controlling EG erosion,and sediment yield of geocell and coir geotextile was reduced by 25.95%–37.82%and 73.73%–88.96%,respectively.However,when confluence intensity increased to 40 L/min,protective effect of coir geotextile decreased,and sediment yield rate increased sharply by 189.03%.When confluence intensity increased to 50 L/min,the protective effect of coir geotextile was lost.On the other hand,geocell showed that the greater the flow rate,the better the protective effect.In addition,with the increase in confluence intensity,erosion pattern of coir geotextile developed from sheet erosion to intermittent fall and then to completion of main rill,and the protective effect was gradually weakened.In contrast,the protective effect of EG under geocell was gradually enhanced from the continuous rill to the intermittent rill and finally to the intermittent fall.This study shows that coir geotextile and geocell can prevent EG erosion,and the effect of geocell is better than that of coir geotextile on the surface of EG.

Bio-cementation for tidal erosion resistance improvement of foreshore slopes based on microbially induced magnesium and calcium precipitation

In most coastal and estuarine areas,tides easily cause surface erosion and even slope failure,resulting in severe land losses,deterioration of coastal infrastructure,and increased floods.The bio-cementation technique has been previously demonstrated to effectively improve the erosion resistance of slopes.Seawater contains magnesium ions(Mg^(2+))with a higher concentration than calcium ions(Ca^(2+));therefore,Mg^(2+)and Ca^(2+)were used together for bio-cementation in this study at various Mg^(2+)/Ca^(2+)ratios as the microbially induced magnesium and calcium precipitation(MIMCP)treatment.Slope angles,surface strengths,precipitation contents,major phases,and microscopic characteristics of precipitation were used to evaluate the treatment effects.Results showed that the MIMCP treatment markedly enhanced the erosion resistance of slopes.Decreased Mg^(2+)/Ca^(2+)ratios resulted in a smaller change in angles and fewer soil losses,especially the Mg^(2+)concentration below 0.2 M.The decreased Mg^(2+)/Ca^(2+)ratio achieved increased precipitation contents,which contributed to better erosion resistance and higher surface strengths.Additionally,the production of aragonite would benefit from elevated Mg^(2+)concentrations and a higher Ca^(2+)concentration led to more nesquehonite in magnesium precipitation crystals.The slopes with an initial angle of 53°had worse erosion resistance than the slopes with an initial angle of 35°,but the Mg^(2+)/Ca^(2+)ratios of 0.2:0.8,0.1:0.9,and 0:1.0 were effective for both slope stabilization and erosion mitigation to a great extent.The results are of great significance for the application of MIMCP to improve erosion resistance of foreshore slopes and the MIMCP technique has promising application potential in marine engineering.