Oil spill-induced vapor cloud explosions in a confined space can cause catastrophic consequences.In this work,investigation was conducted on the catastrophic pipeline leak,oil spill,and the resulting vapor cloud explo...Oil spill-induced vapor cloud explosions in a confined space can cause catastrophic consequences.In this work,investigation was conducted on the catastrophic pipeline leak,oil spill,and the resulting vapor cloud explosion accident occurring in China in 2013 by modeling analysis,field surveys,and numerical simulations.The total amount of the spilled oil was up to2044.4 m3 due to improper disposal.The long residence time of the oil remaining in a confined space permitted the formation of explosive mixtures and caused the vapor cloud explosion.A numerical model was developed to estimate the consequence of the explosion based on volatilization testing results.The results show that the death-leading zone and the glass-breaking zone could be 18 m and 92 m,respectively,which are consistent with the field investigation.The severity of the explosion is related to the amount of the oil spill,properties of oil,and volatilization time.It is recommended that a comprehensive risk assessment be conducted to analyze the possible consequences upon oil spilling into a confined space.Prompt collection and ventilation measures should be taken immediately after the spill occurs to reduce the time for oil volatilization and prevent the mixture from reaching its explosive limit.展开更多
Based on the non-linear air leakage seepage equation for an anisotropic porous medium, on the seepage diffusion equation of multicomponent gas and on the seepage synthetic heat transfer equation of a porous medium, th...Based on the non-linear air leakage seepage equation for an anisotropic porous medium, on the seepage diffusion equation of multicomponent gas and on the seepage synthetic heat transfer equation of a porous medium, the numerical model for field flow problems of irregular patterns of a goaf with multiple points of leaking air is established and simultaneously solved by the upwind mode finite element method (G3 computer program). According to the complexity of irregular patterns of a goaf with multiple points of leaking air, the flow pattern in a large area of such a goaf and the variation in gases of methane, oxygen and CO and in temperature are theoretically described. In the calculation, the goaf is regarded as a caving anisotropic medium and the coupling effect of methane effusion on spontaneous combustion is considered. The simulation results agree well with practical experience. In addition, the spontaneous combustion process is also simulated, indicating that 1) the spontaneous combustion often takes place near the area where fresh air leaks in and 2) the fire sources can be classified into static and dynamic zones. Therefore, in practical fire preventing and extinguishing, we should clearly distinguish the upstream air leaking points from the downstream ones in order to take proper measures for leakage stopping.展开更多
Molten salt is often used for heat transfer and thermal energy storage in concentrated solar power.Molten salt leakage and migration is a significant issue in its application.Molten salt migration and solidification i...Molten salt is often used for heat transfer and thermal energy storage in concentrated solar power.Molten salt leakage and migration is a significant issue in its application.Molten salt migration and solidification in thermal porous foundation materials through cracks are experimentally investigated.The impact of factors,including crack length and width,operation temperature,and leakage mass of molten salt,are studied through an experimental device modeling the leakage of the actual molten salt storage tank.Experimental results show that the crack width and length slightly affect the migration depth,but directly affect the shape of the agglomeration of solidified salt and porous foundation material.The most important factor affecting the migration depth of molten salt leaking through cracks is the tank operating temperature.The molten salt migration depth when the operating temperature is 500℃ is 95.8% higher than that with an operating temperature of 300℃.As the leakage molten salt mass reached 400 g,the average migration width increased by 23.6%,but the migration depth only increased by 5.2%.It is found that the foundation material temperatures after leakage accidents increase with an increase in the mass of leaked molten salt.展开更多
Dear Editor,In a recent interventional case report,Allon et al ）hydrated corneal stroma with cefuroxime to seal a small traumatic leaky corneal perforation that was unresponsive to prior soft bandage contact lens app...Dear Editor,In a recent interventional case report,Allon et al ）hydrated corneal stroma with cefuroxime to seal a small traumatic leaky corneal perforation that was unresponsive to prior soft bandage contact lens application for 6d.展开更多
In order to develop the technology of the controlled recircuIation of airflow in the world, some formulas about the airflow recirculation system in the working face with leaking airflow are deduced,which reduces the e...In order to develop the technology of the controlled recircuIation of airflow in the world, some formulas about the airflow recirculation system in the working face with leaking airflow are deduced,which reduces the error between calculating and real values. on the base of the application of the formulas mentioned above, the problem about lack of airflow in the working face 2712 was solved successfully in Xiandewang Coal Mine.展开更多
AIM:To introduce and evaluate the clinical efficacy of a new technique,the use of viscoelastic substances(VS)to close leaking sclerotomy in 23G microincision vitrectomy,and to observe its effect on the visual acuity a...AIM:To introduce and evaluate the clinical efficacy of a new technique,the use of viscoelastic substances(VS)to close leaking sclerotomy in 23G microincision vitrectomy,and to observe its effect on the visual acuity and intraocular pressure(IOP)of patients.METHODS:Patients who underwent 23G vitrectomy in Ningbo Eye Hospital before the use of VS technique(June 2019 to September 2020)and after the use of VS technique(October 2020 to December 2021)were selected as the subjects of this study.The above cases underwent operation by the same surgeon and were retrospectively analyzed.VS technique was used as the alternative to suturing,in which a small amount of VS was injected at the leaking sclerotomy and then gently massaged to confirm leaking sclerotomy closure.RESULTS:A total of 174 eyes were covered in the study,including 84 eyes in the control group(before the use of VS technique)and 90 eyes in the VS technique group.The number of eyes that needed to be sutured decreased considerably from 42.9%in the control group to 3.3%in the VS technique group,and the proportion of subconjunctival hemorrhage at 1-2d after surgery decreased remarkably from 35.7%in the control group to 2.2%in the VS technique group.No substantial differences in the incidence of mean IOP and low IOP were found between 1-2 and 3-20d after surgery in the VS technique group.No major complications associated with VS technique were identified during the study.CONCLUSION:In 23G microincision vitrectomy,VS technique is a safe,simple,and effective method to close leaking sclerotomy.展开更多
This paper deals with the temperature and displacement fields of the top mid block of south transition at Long Spruce Generating Station, in the North of Manitoba, Canada. According to the experimental results of Man...This paper deals with the temperature and displacement fields of the top mid block of south transition at Long Spruce Generating Station, in the North of Manitoba, Canada. According to the experimental results of Manitoba Hydro in the past two years, the top mid block is assumed to be a rectangular one that has two supposed temperature distributions at its boundary sides. Then, the temperature fields for the top mid block are obtained from the analytical solutions by separation of variables. By using the analytical solution of temperature field, the displacement behavior of the top block in various temperature fields is discussed in details. The numerical results are given to show the causes of the leakage between the top mid block and the dam. Finally, the repair methods for leakage are discussed for practical leaking repair and its engineering applications.展开更多
Gardening style in south of the Yangtze River was reviewed, and aesthetic features of local gardens were summarized as full of humanistic connotations, modeling after the nature, graceful and free from vulgarity, refi...Gardening style in south of the Yangtze River was reviewed, and aesthetic features of local gardens were summarized as full of humanistic connotations, modeling after the nature, graceful and free from vulgarity, refined and refreshing, implying profound significance in detailed designs, integrated virtual and real scenery. On this basis, form and meaning of leaking windows in the gardens were analyzed, and artistic means of designing leaking windows were summarized from the perspectives of leaking through scenery and borrowed scenery, virtual and real scenery, in-motion and in-position scenery.展开更多
BACKGROUND The root of mesentery dissection is one of the critical maneuvers,especially in borderline resectable pancreatic head cancer.Intra-abdominal chyle leak(CL)including chylous ascites may ensue in up to 10%of ...BACKGROUND The root of mesentery dissection is one of the critical maneuvers,especially in borderline resectable pancreatic head cancer.Intra-abdominal chyle leak(CL)including chylous ascites may ensue in up to 10%of patients after pancreatic resections.Globally recognized superior mesenteric artery(SMA)first approaches are invariably performed.The mesenteric dissection through the inferior infracolic approach has been discussed in this study emphasizing its post-operative impact on CL which is the cornerstone of this study.AIM To assess incidence,risk factors,clinical impact of CL following root of mesentery dissection,and the different treatment modalities.METHODS This is a retrospective study incorporating the patients who underwent dissection of the root of mesentery with inferior infracolic SMA first approach pancreat-oduodenectomy for the ventral body and uncinate mass of pancreas in the Department of Gastrointestinal and General Surgery of Kathmandu Medical College and Teaching Hospital from January 1,2021 to February 28,2024.Intraop-erative findings and postoperative outcomes were analyzed.RESULTS In three years,ten patients underwent root of mesentery dissection with inferior infracolic SMA first approach pancreatoduodenectomy.The mean age was 67.6 years with a male-to-female ratio of 4:5.CL was seen in four patients.With virtue of CL,Clavien-Dindo grade Ⅱ or higher morbidity was observed in four patients.Two patients had a hospital stay of more than 20 days with the former having a delayed gastric emptying and the latter with long-term total parenteral nutrition requirement.The mean operative time was 330 minutes.Curative resection was achieved in 100%of the patients.The mean duration of the intensive care unit and hospital stay were 2.55±1.45 days and 15.7±5.32 days,respectively.CONCLUSION Root of mesentery dissection with lymphadenectomy and vascular resection correlated with occurrence of CL.After complete curative resection,these were managed with total parenteral nutrition without adversely impacting outcome.展开更多
Dear Editor,The incidence of complications associated with ventriculoperitoneal(VP)shunts ranges from 24%to 47%,with abdominal complications comprising 25%of these cases[1].The shunt may migrate to various body parts,...Dear Editor,The incidence of complications associated with ventriculoperitoneal(VP)shunts ranges from 24%to 47%,with abdominal complications comprising 25%of these cases[1].The shunt may migrate to various body parts,including the abdominal wall,gastrointestinal tract,vagina,bladder,scrotum,mediastinum,and the oral cavity.Cerebrospinal fluid(CSF)leakage through the vagina is an uncommon complication of VP shunts;however,its exact incidence remains unknown.Such complications can result in failure of the shunt procedure,often requiring revision or reinsertion in affected patients[2].展开更多
BACKGROUND Laparoscopic one anastomosis gastric bypass(OAGB)has grown in popularity in recent years for the treatment of morbid obesity.Despite routine practice,the utility of early postoperative upper gastrointestina...BACKGROUND Laparoscopic one anastomosis gastric bypass(OAGB)has grown in popularity in recent years for the treatment of morbid obesity.Despite routine practice,the utility of early postoperative upper gastrointestinal(UGI)swallow studies to detect complications following OAGB has been questioned.AIM To evaluate the effectiveness and cost-efficiency of performing routine UGI studies on the first postoperative day(POD)after OAGB.METHODS A retrospective cohort analysis of a prospectively collected database was conducted to identify all consecutive patients who underwent OAGB between January 2019 and July 2022.Patient demographics,operative data,and postoperative complication rates were analyzed.Reports from all imaging studies were retrospectively reviewed,and complications were recorded.The institutional review board waived the requirement for informed consent.RESULTS A total of 385 patients were included.All patients had an iodine-based contrast swallow study on the first POD.Abnormal findings were observed in 4 patients(1%),none of which were correlated with postoperative complications.Two patients(0.5%)required reoperation due to complications although both had normal UGI study results.Sensitivity and positive predictive value of UGI studies for detecting complications were 0%,while specificity and negative predictive value were 99%and 98%,respectively.Based on hospital charges the overall cost of all the UGI swallow studies performed in our study was 95865 USD.CONCLUSION The study findings showed that performing routine UGI swallow studies on the first POD after laparoscopic OAGB is ineffective in detecting complications and is not cost effective.Normal UGI studies might mislead clinicians in the postoperative period and thus should be omitted in favor of close clinical monitoring.展开更多
Gastrointestinal(GI)tract defects can be classified into three distinct entities:Leak,perforation,and fistula.Each arises from different mechanisms and is managed accordingly.Leaks occur most often after surgery,while...Gastrointestinal(GI)tract defects can be classified into three distinct entities:Leak,perforation,and fistula.Each arises from different mechanisms and is managed accordingly.Leaks occur most often after surgery,while perforations arise due to flexible endoscopic maneuvers.Fistulae arise from a variety of mechanisms,including specific disease states.Endoscopic management is vital in treating such defects if the region of interest can be accessed with the appropriate endoscopic accessories.The primary goal of endoscopic therapy is to interrupt the flow of luminal contents across a GI defect.Considering the proper endoscopic approach to luminal closure,several basic principles must be considered.Outcomes are dependent on the size and exact location of the leak/fistula,as well as the viability of the surrounding tissue.Almost all complex leaks and fistulae must be approached in a multidisciplinary manner,collaborating with colleagues in nutrition,radiology,and surgery.With advances in technology,a myriad of devices and accessories are available that allow a tailored approach.In this review,we discuss these modalities,provide technical tips,and review published outcomes data regarding each approach,as well as practical considerations for the successful closure of these defects.展开更多
Anastomotic leakage(AL)is a significant complication following rectal cancer surgery,adversely affecting both quality of life and oncological outcomes.Recent advancements in artificial intelligence(AI),particularly ma...Anastomotic leakage(AL)is a significant complication following rectal cancer surgery,adversely affecting both quality of life and oncological outcomes.Recent advancements in artificial intelligence(AI),particularly machine learning and deep learning,offer promising avenues for predicting and preventing AL.These technologies can analyze extensive clinical datasets to identify preoperative and perioperative risk factors such as malnutrition,body composition,and radiological features.AI-based models have demonstrated superior predictive power compared to traditional statistical methods,potentially guiding clinical decisionmaking and improving patient outcomes.Additionally,AI can provide surgeons with intraoperative feedback on blood supply and anatomical dissection planes,minimizing the risk of intraoperative complications and reducing the likelihood of AL development.展开更多
BACKGROUND Bile spillage occurs more frequently in patients with incidental gallbladder carcinoma(iGBC)and may be associated with poor survival due to presumed high risk of peritoneal seeding.AIM To investigate the im...BACKGROUND Bile spillage occurs more frequently in patients with incidental gallbladder carcinoma(iGBC)and may be associated with poor survival due to presumed high risk of peritoneal seeding.AIM To investigate the impact of bile spillage during primary surgery on the survival of patients with iGBC.METHODS Medical records of patients with iGBC diagnosed between 2000 and 2019 in 27 Dutch secondary centers and 5 tertiary centers were retrospectively reviewed.Patient medical records were assessed.Predictors for overall survival(OS)were determined using multivariable Cox regression.RESULTS Of the 346 included patients with iGBC,138(39.9%)had bile spillage,which was associated with higher American Society of Anesthesiologists classification(P=0.020),cholecystitis(P<0.001),higher tumor stage(P=0.005),and non-radical resection(P<0.001).Bile spillage was associated with poor OS[hazard ratio=1.97,95%confidence interval(CI):1.48-2.63,P<0.001]with a median OS of 12 months(95%CI:7-18 months)vs 34 months(95%CI:14-55 months,P<0.001).In multivariable analysis,spillage was not an independent prognostic factor for survival(hazard ratio=1.21,95%CI:0.84-1.74,P=0.313).CONCLUSION Although bile spillage correlates with prognostic factors,it lacks independent prognostic significance for survival.Patients with an indication for additional treatment should be promptly referred to a specialized hepatopancreatobiliary center,irrespective of whether bile spillage has occurred.展开更多
Sound speed is essential for leakage detection in liquid pipelines when using acoustic methods,which can be significantly influenced by gas bubbles generated from leakage.The propagation characteristics and mechanism ...Sound speed is essential for leakage detection in liquid pipelines when using acoustic methods,which can be significantly influenced by gas bubbles generated from leakage.The propagation characteristics and mechanism of acoustic waves in horizontal liquid pipelines containing gas bubbles are studied in detail in the present paper.The effect of sound wave frequency,bubble size and bubble distribution pattern on sound speed is studied through numerical simulations.The results show that the acoustic wave generated by leakage of liquid pipelines containing gas bubbles is a multi-frequency signal,and the energy of the signal is mainly concentrated within 200 Hz.In the low-frequency range,the propagation of sound waves has almost no dispersion in bubbly liquid.Sound speed at a certain void fraction is not constant,which is related to the bubble size and distribution pattern.The bubble size affects the gasliquid heat transfer equilibrium,during which sound speed is affected.For this reason,a thermodynamic correction factor is proposed,which enables the accuracy of the sound speed calculation to reach98.2%.What's more,sound speed increases non-linearly with the reduction of the bubble distribution space in the pipeline axial direction.This paper establishes a theoretical calculation model of sound speed based on the bubble distribution pattern in the pipeline axial direction,which is in good agreement with the numerical calculation results.The results of this paper provide the basis for applying acoustic leak detection technology in liquid pipelines containing gas bubbles.展开更多
We read with great interest the case report by Zhang et al describing unusual complications after endoscopic ultrasound-guided hepaticogastrostomy(EUSHGS)in a patient with pancreatic cancer.The patient developed dark ...We read with great interest the case report by Zhang et al describing unusual complications after endoscopic ultrasound-guided hepaticogastrostomy(EUSHGS)in a patient with pancreatic cancer.The patient developed dark green urine,bile-colored pleural effusion,and ascites,suggesting bile leak and possible biliaryvascular fistula.We believe the complication profile is more consistent with transdiaphragmatic bile leakage during segment 2 puncture,as microperforation near the diaphragm can explain bilothorax.Device selection for fistula dilation and stent type may also have contributed.High pleural fluid-to-serum bilirubin ratios further support the diagnosis of bile leak,with urinary discoloration likely reflecting systemic absorption.This rare case highlights the need for refined techniques,careful puncture site selection,and dedicated devices to enhance safety in EUS-HGS.展开更多
The clinicians remain uncertain about the ideal timing for loop ileostomy reversal following rectal resection surgery.The common practice of waiting 8-12 weeks to protect from anastomotic complication,especially in pa...The clinicians remain uncertain about the ideal timing for loop ileostomy reversal following rectal resection surgery.The common practice of waiting 8-12 weeks to protect from anastomotic complication,especially in patients who receive neoadjuvant chemoradiotherapy,would expose patients to dehydration,electrolyte disturbances,stoma related complications,and reduced quality of life.Randomized controlled trials have studied early reversal of ileostomy,with results ranging from improved outcomes in selected patients to increased morbidity when applied indiscriminately.Meta-analyses have also yielded heterogeneous findings,reflecting the need for careful patient selection.The study byÖzcan and Düzgün used retrospective methods to show that patients who underwent early closure experienced similar complication rates to those who had late closure,but early closure were associated with better quality of life.Taken together,current evidence suggests that reversal within 2-4 weeks may be safe and beneficial in meticulously selected patients with an intact anastomosis and an uneventful postoperative course.Their study provides practical data supporting early closure.It is limited,however,by being retrospective with a short follow-up period,which may leave important concerns unaddressed.Multicenter randomized trials are required to help establish safe standardized criteria for early closure and longterm safety.展开更多
Studies have indicated that approximately half of individuals with Crohn’s disease(CD)may undergo surgery at some point during their lifetime.Ileocolic resection(ICR)is the most frequently performed procedure for tre...Studies have indicated that approximately half of individuals with Crohn’s disease(CD)may undergo surgery at some point during their lifetime.Ileocolic resection(ICR)is the most frequently performed procedure for treating CD.Addressing anastomotic leak(AL)remains a critical focus in the perioperative and postoperative care of CD patients.A research study published in the World Journal of Gastrointestinal Surgery by Cwaliński et al included 77 individuals who had open ICR and primary stapled anastomosis to assess the risk factors linked to anastomotic insufficiency.At present,research on anastomotic insufficiency has focused on AL.Therefore,this editorial mainly analyzes the current risk factors linked to AL after ICR and discusses potential prevention strategies.We comprehensively consider risk factors such as body weight,medication use,surgical history,smoking,penetrating behaviour,and albumin levels to stratify patient risk.Based on recent research insights,we propose that individualized surgical timing,approaches,and techniques should be selected according to the patient's risk level.展开更多
Post-esophagectomy anastomotic leak(AL)is a severe complication following esophagectomy,contributing to increased morbidity,prolonged hospitalization,and a significant risk of mortality.Endoscopic vacuum-assisted clos...Post-esophagectomy anastomotic leak(AL)is a severe complication following esophagectomy,contributing to increased morbidity,prolonged hospitalization,and a significant risk of mortality.Endoscopic vacuum-assisted closure(EndoVac)has emerged as a promising first-line treatment,offering a highly effective approach for managing post-esophagectomy AL.EndoVac therapy utilizes continuous negative pressure within the esophageal lumen or mediastinal cavity,promoting granulation tissue formation,accelerating wound healing,and enhancing AL closure rates.Compared to stenting,EndoVac provides distinct advantages,including superior adaptability to varying leak sizes and locations,enhanced secretion drainage,and lower rates of reintervention.Clinical studies have demonstrated higher success rates,decreased post-intervention complications,and shorter hospital stays.Despite its advantages,challenges persist in patient selection,procedural expertise,and accessibility.EndoVac application requires experienced endoscopic teams and multidisciplinary expertise,which is best achieved in high-volume centers with specialized care.Variability in EndoVac protocols necessitate further refinement and standardization to optimize treatment outcomes.The integration of EndoVac into standardized treatment guidelines holds promise for improving patient outcomes and redefining the management approach for this challenging postoperative complication.展开更多
BACKGROUND Endoscopic ultrasound-guided biliary drainage,including endoscopic ultrasoundguided choledochoduodenostomy and endoscopic ultrasound-guided hepatogastrostomy(EUS-HGS),is an efficacious alternative to endosc...BACKGROUND Endoscopic ultrasound-guided biliary drainage,including endoscopic ultrasoundguided choledochoduodenostomy and endoscopic ultrasound-guided hepatogastrostomy(EUS-HGS),is an efficacious alternative to endoscopic retrograde cholangiopancreatography and its common complications are bile leak,infection,stent migration and bleeding.Here,we report an atypical case of a patient who developed unexplained dark green urine after receiving EUS-HGS,which we suspected to be caused by an abnormal biliary-vascular fistula.CASE SUMMARY A 76-year-old woman diagnosed with pancreatic adenocarcinoma received EUSHGS for relieving jaundice.The patient reported abdominal pain and chest tightness after the operation,with difficulty in urinating.X-ray suggested rightsided pleural effusion and dark green pleural effusion was drained out.However,the patient also developed dark green urine,which appeared everyday afternoon and disappeared automatically after intravenous treatment.The previous pleural effusion disappeared after one week,but later the patient showed an increase of ascites,and the lesions were compartmentalized and encapsulated internally.CONCLUSION Postoperative surveillance after EUS-HGS must be emphasized to check for in order to prevent severe and hidden complications.展开更多
基金supported by China Scholarship Council(201809110035)the State Key Research and Development Plan Project of China(2016YFC0801500).
文摘Oil spill-induced vapor cloud explosions in a confined space can cause catastrophic consequences.In this work,investigation was conducted on the catastrophic pipeline leak,oil spill,and the resulting vapor cloud explosion accident occurring in China in 2013 by modeling analysis,field surveys,and numerical simulations.The total amount of the spilled oil was up to2044.4 m3 due to improper disposal.The long residence time of the oil remaining in a confined space permitted the formation of explosive mixtures and caused the vapor cloud explosion.A numerical model was developed to estimate the consequence of the explosion based on volatilization testing results.The results show that the death-leading zone and the glass-breaking zone could be 18 m and 92 m,respectively,which are consistent with the field investigation.The severity of the explosion is related to the amount of the oil spill,properties of oil,and volatilization time.It is recommended that a comprehensive risk assessment be conducted to analyze the possible consequences upon oil spilling into a confined space.Prompt collection and ventilation measures should be taken immediately after the spill occurs to reduce the time for oil volatilization and prevent the mixture from reaching its explosive limit.
基金supported by the National Natural Science Foundation of China (No.50574038)the Scientific Research Foundation of Liaoning Technical University (No.2004-241).
文摘Based on the non-linear air leakage seepage equation for an anisotropic porous medium, on the seepage diffusion equation of multicomponent gas and on the seepage synthetic heat transfer equation of a porous medium, the numerical model for field flow problems of irregular patterns of a goaf with multiple points of leaking air is established and simultaneously solved by the upwind mode finite element method (G3 computer program). According to the complexity of irregular patterns of a goaf with multiple points of leaking air, the flow pattern in a large area of such a goaf and the variation in gases of methane, oxygen and CO and in temperature are theoretically described. In the calculation, the goaf is regarded as a caving anisotropic medium and the coupling effect of methane effusion on spontaneous combustion is considered. The simulation results agree well with practical experience. In addition, the spontaneous combustion process is also simulated, indicating that 1) the spontaneous combustion often takes place near the area where fresh air leaks in and 2) the fire sources can be classified into static and dynamic zones. Therefore, in practical fire preventing and extinguishing, we should clearly distinguish the upstream air leaking points from the downstream ones in order to take proper measures for leakage stopping.
基金Project supported by the National Natural Science Foundation of China(No.52036008)。
文摘Molten salt is often used for heat transfer and thermal energy storage in concentrated solar power.Molten salt leakage and migration is a significant issue in its application.Molten salt migration and solidification in thermal porous foundation materials through cracks are experimentally investigated.The impact of factors,including crack length and width,operation temperature,and leakage mass of molten salt,are studied through an experimental device modeling the leakage of the actual molten salt storage tank.Experimental results show that the crack width and length slightly affect the migration depth,but directly affect the shape of the agglomeration of solidified salt and porous foundation material.The most important factor affecting the migration depth of molten salt leaking through cracks is the tank operating temperature.The molten salt migration depth when the operating temperature is 500℃ is 95.8% higher than that with an operating temperature of 300℃.As the leakage molten salt mass reached 400 g,the average migration width increased by 23.6%,but the migration depth only increased by 5.2%.It is found that the foundation material temperatures after leakage accidents increase with an increase in the mass of leaked molten salt.
文摘Dear Editor,In a recent interventional case report,Allon et al ）hydrated corneal stroma with cefuroxime to seal a small traumatic leaky corneal perforation that was unresponsive to prior soft bandage contact lens application for 6d.
文摘In order to develop the technology of the controlled recircuIation of airflow in the world, some formulas about the airflow recirculation system in the working face with leaking airflow are deduced,which reduces the error between calculating and real values. on the base of the application of the formulas mentioned above, the problem about lack of airflow in the working face 2712 was solved successfully in Xiandewang Coal Mine.
基金Supported by General Class A of the Zhejiang Medical and Health Science and Technique Plan Project in 2020(No.2020ky288)Zhejiang Provincial Science and Technique Program of Traditional Chinese Medicine(No.2021ZB268)+2 种基金Health Science and Technique Program of Zhejiang Province(No.2021PY073)Yinzhou District Agriculture and Social Development Field Science and Technique Project(No.2021AS0058No.2020AS0080)。
文摘AIM:To introduce and evaluate the clinical efficacy of a new technique,the use of viscoelastic substances(VS)to close leaking sclerotomy in 23G microincision vitrectomy,and to observe its effect on the visual acuity and intraocular pressure(IOP)of patients.METHODS:Patients who underwent 23G vitrectomy in Ningbo Eye Hospital before the use of VS technique(June 2019 to September 2020)and after the use of VS technique(October 2020 to December 2021)were selected as the subjects of this study.The above cases underwent operation by the same surgeon and were retrospectively analyzed.VS technique was used as the alternative to suturing,in which a small amount of VS was injected at the leaking sclerotomy and then gently massaged to confirm leaking sclerotomy closure.RESULTS:A total of 174 eyes were covered in the study,including 84 eyes in the control group(before the use of VS technique)and 90 eyes in the VS technique group.The number of eyes that needed to be sutured decreased considerably from 42.9%in the control group to 3.3%in the VS technique group,and the proportion of subconjunctival hemorrhage at 1-2d after surgery decreased remarkably from 35.7%in the control group to 2.2%in the VS technique group.No substantial differences in the incidence of mean IOP and low IOP were found between 1-2 and 3-20d after surgery in the VS technique group.No major complications associated with VS technique were identified during the study.CONCLUSION:In 23G microincision vitrectomy,VS technique is a safe,simple,and effective method to close leaking sclerotomy.
文摘This paper deals with the temperature and displacement fields of the top mid block of south transition at Long Spruce Generating Station, in the North of Manitoba, Canada. According to the experimental results of Manitoba Hydro in the past two years, the top mid block is assumed to be a rectangular one that has two supposed temperature distributions at its boundary sides. Then, the temperature fields for the top mid block are obtained from the analytical solutions by separation of variables. By using the analytical solution of temperature field, the displacement behavior of the top block in various temperature fields is discussed in details. The numerical results are given to show the causes of the leakage between the top mid block and the dam. Finally, the repair methods for leakage are discussed for practical leaking repair and its engineering applications.
文摘Gardening style in south of the Yangtze River was reviewed, and aesthetic features of local gardens were summarized as full of humanistic connotations, modeling after the nature, graceful and free from vulgarity, refined and refreshing, implying profound significance in detailed designs, integrated virtual and real scenery. On this basis, form and meaning of leaking windows in the gardens were analyzed, and artistic means of designing leaking windows were summarized from the perspectives of leaking through scenery and borrowed scenery, virtual and real scenery, in-motion and in-position scenery.
文摘BACKGROUND The root of mesentery dissection is one of the critical maneuvers,especially in borderline resectable pancreatic head cancer.Intra-abdominal chyle leak(CL)including chylous ascites may ensue in up to 10%of patients after pancreatic resections.Globally recognized superior mesenteric artery(SMA)first approaches are invariably performed.The mesenteric dissection through the inferior infracolic approach has been discussed in this study emphasizing its post-operative impact on CL which is the cornerstone of this study.AIM To assess incidence,risk factors,clinical impact of CL following root of mesentery dissection,and the different treatment modalities.METHODS This is a retrospective study incorporating the patients who underwent dissection of the root of mesentery with inferior infracolic SMA first approach pancreat-oduodenectomy for the ventral body and uncinate mass of pancreas in the Department of Gastrointestinal and General Surgery of Kathmandu Medical College and Teaching Hospital from January 1,2021 to February 28,2024.Intraop-erative findings and postoperative outcomes were analyzed.RESULTS In three years,ten patients underwent root of mesentery dissection with inferior infracolic SMA first approach pancreatoduodenectomy.The mean age was 67.6 years with a male-to-female ratio of 4:5.CL was seen in four patients.With virtue of CL,Clavien-Dindo grade Ⅱ or higher morbidity was observed in four patients.Two patients had a hospital stay of more than 20 days with the former having a delayed gastric emptying and the latter with long-term total parenteral nutrition requirement.The mean operative time was 330 minutes.Curative resection was achieved in 100%of the patients.The mean duration of the intensive care unit and hospital stay were 2.55±1.45 days and 15.7±5.32 days,respectively.CONCLUSION Root of mesentery dissection with lymphadenectomy and vascular resection correlated with occurrence of CL.After complete curative resection,these were managed with total parenteral nutrition without adversely impacting outcome.
文摘Dear Editor,The incidence of complications associated with ventriculoperitoneal(VP)shunts ranges from 24%to 47%,with abdominal complications comprising 25%of these cases[1].The shunt may migrate to various body parts,including the abdominal wall,gastrointestinal tract,vagina,bladder,scrotum,mediastinum,and the oral cavity.Cerebrospinal fluid(CSF)leakage through the vagina is an uncommon complication of VP shunts;however,its exact incidence remains unknown.Such complications can result in failure of the shunt procedure,often requiring revision or reinsertion in affected patients[2].
文摘BACKGROUND Laparoscopic one anastomosis gastric bypass(OAGB)has grown in popularity in recent years for the treatment of morbid obesity.Despite routine practice,the utility of early postoperative upper gastrointestinal(UGI)swallow studies to detect complications following OAGB has been questioned.AIM To evaluate the effectiveness and cost-efficiency of performing routine UGI studies on the first postoperative day(POD)after OAGB.METHODS A retrospective cohort analysis of a prospectively collected database was conducted to identify all consecutive patients who underwent OAGB between January 2019 and July 2022.Patient demographics,operative data,and postoperative complication rates were analyzed.Reports from all imaging studies were retrospectively reviewed,and complications were recorded.The institutional review board waived the requirement for informed consent.RESULTS A total of 385 patients were included.All patients had an iodine-based contrast swallow study on the first POD.Abnormal findings were observed in 4 patients(1%),none of which were correlated with postoperative complications.Two patients(0.5%)required reoperation due to complications although both had normal UGI study results.Sensitivity and positive predictive value of UGI studies for detecting complications were 0%,while specificity and negative predictive value were 99%and 98%,respectively.Based on hospital charges the overall cost of all the UGI swallow studies performed in our study was 95865 USD.CONCLUSION The study findings showed that performing routine UGI swallow studies on the first POD after laparoscopic OAGB is ineffective in detecting complications and is not cost effective.Normal UGI studies might mislead clinicians in the postoperative period and thus should be omitted in favor of close clinical monitoring.
文摘Gastrointestinal(GI)tract defects can be classified into three distinct entities:Leak,perforation,and fistula.Each arises from different mechanisms and is managed accordingly.Leaks occur most often after surgery,while perforations arise due to flexible endoscopic maneuvers.Fistulae arise from a variety of mechanisms,including specific disease states.Endoscopic management is vital in treating such defects if the region of interest can be accessed with the appropriate endoscopic accessories.The primary goal of endoscopic therapy is to interrupt the flow of luminal contents across a GI defect.Considering the proper endoscopic approach to luminal closure,several basic principles must be considered.Outcomes are dependent on the size and exact location of the leak/fistula,as well as the viability of the surrounding tissue.Almost all complex leaks and fistulae must be approached in a multidisciplinary manner,collaborating with colleagues in nutrition,radiology,and surgery.With advances in technology,a myriad of devices and accessories are available that allow a tailored approach.In this review,we discuss these modalities,provide technical tips,and review published outcomes data regarding each approach,as well as practical considerations for the successful closure of these defects.
文摘Anastomotic leakage(AL)is a significant complication following rectal cancer surgery,adversely affecting both quality of life and oncological outcomes.Recent advancements in artificial intelligence(AI),particularly machine learning and deep learning,offer promising avenues for predicting and preventing AL.These technologies can analyze extensive clinical datasets to identify preoperative and perioperative risk factors such as malnutrition,body composition,and radiological features.AI-based models have demonstrated superior predictive power compared to traditional statistical methods,potentially guiding clinical decisionmaking and improving patient outcomes.Additionally,AI can provide surgeons with intraoperative feedback on blood supply and anatomical dissection planes,minimizing the risk of intraoperative complications and reducing the likelihood of AL development.
文摘BACKGROUND Bile spillage occurs more frequently in patients with incidental gallbladder carcinoma(iGBC)and may be associated with poor survival due to presumed high risk of peritoneal seeding.AIM To investigate the impact of bile spillage during primary surgery on the survival of patients with iGBC.METHODS Medical records of patients with iGBC diagnosed between 2000 and 2019 in 27 Dutch secondary centers and 5 tertiary centers were retrospectively reviewed.Patient medical records were assessed.Predictors for overall survival(OS)were determined using multivariable Cox regression.RESULTS Of the 346 included patients with iGBC,138(39.9%)had bile spillage,which was associated with higher American Society of Anesthesiologists classification(P=0.020),cholecystitis(P<0.001),higher tumor stage(P=0.005),and non-radical resection(P<0.001).Bile spillage was associated with poor OS[hazard ratio=1.97,95%confidence interval(CI):1.48-2.63,P<0.001]with a median OS of 12 months(95%CI:7-18 months)vs 34 months(95%CI:14-55 months,P<0.001).In multivariable analysis,spillage was not an independent prognostic factor for survival(hazard ratio=1.21,95%CI:0.84-1.74,P=0.313).CONCLUSION Although bile spillage correlates with prognostic factors,it lacks independent prognostic significance for survival.Patients with an indication for additional treatment should be promptly referred to a specialized hepatopancreatobiliary center,irrespective of whether bile spillage has occurred.
基金supported by the National Natural Science Foundation of China[grant number 52274066]。
文摘Sound speed is essential for leakage detection in liquid pipelines when using acoustic methods,which can be significantly influenced by gas bubbles generated from leakage.The propagation characteristics and mechanism of acoustic waves in horizontal liquid pipelines containing gas bubbles are studied in detail in the present paper.The effect of sound wave frequency,bubble size and bubble distribution pattern on sound speed is studied through numerical simulations.The results show that the acoustic wave generated by leakage of liquid pipelines containing gas bubbles is a multi-frequency signal,and the energy of the signal is mainly concentrated within 200 Hz.In the low-frequency range,the propagation of sound waves has almost no dispersion in bubbly liquid.Sound speed at a certain void fraction is not constant,which is related to the bubble size and distribution pattern.The bubble size affects the gasliquid heat transfer equilibrium,during which sound speed is affected.For this reason,a thermodynamic correction factor is proposed,which enables the accuracy of the sound speed calculation to reach98.2%.What's more,sound speed increases non-linearly with the reduction of the bubble distribution space in the pipeline axial direction.This paper establishes a theoretical calculation model of sound speed based on the bubble distribution pattern in the pipeline axial direction,which is in good agreement with the numerical calculation results.The results of this paper provide the basis for applying acoustic leak detection technology in liquid pipelines containing gas bubbles.
文摘We read with great interest the case report by Zhang et al describing unusual complications after endoscopic ultrasound-guided hepaticogastrostomy(EUSHGS)in a patient with pancreatic cancer.The patient developed dark green urine,bile-colored pleural effusion,and ascites,suggesting bile leak and possible biliaryvascular fistula.We believe the complication profile is more consistent with transdiaphragmatic bile leakage during segment 2 puncture,as microperforation near the diaphragm can explain bilothorax.Device selection for fistula dilation and stent type may also have contributed.High pleural fluid-to-serum bilirubin ratios further support the diagnosis of bile leak,with urinary discoloration likely reflecting systemic absorption.This rare case highlights the need for refined techniques,careful puncture site selection,and dedicated devices to enhance safety in EUS-HGS.
文摘The clinicians remain uncertain about the ideal timing for loop ileostomy reversal following rectal resection surgery.The common practice of waiting 8-12 weeks to protect from anastomotic complication,especially in patients who receive neoadjuvant chemoradiotherapy,would expose patients to dehydration,electrolyte disturbances,stoma related complications,and reduced quality of life.Randomized controlled trials have studied early reversal of ileostomy,with results ranging from improved outcomes in selected patients to increased morbidity when applied indiscriminately.Meta-analyses have also yielded heterogeneous findings,reflecting the need for careful patient selection.The study byÖzcan and Düzgün used retrospective methods to show that patients who underwent early closure experienced similar complication rates to those who had late closure,but early closure were associated with better quality of life.Taken together,current evidence suggests that reversal within 2-4 weeks may be safe and beneficial in meticulously selected patients with an intact anastomosis and an uneventful postoperative course.Their study provides practical data supporting early closure.It is limited,however,by being retrospective with a short follow-up period,which may leave important concerns unaddressed.Multicenter randomized trials are required to help establish safe standardized criteria for early closure and longterm safety.
基金Supported by National Natural Science Foundation of China,No.NSFC 82070540the Taishan Scholars Program of Shandong Province,No.tsqn202211309ECCM Program of Clinical Research Center of Shandong University,No.2021SDUCRCB003.
文摘Studies have indicated that approximately half of individuals with Crohn’s disease(CD)may undergo surgery at some point during their lifetime.Ileocolic resection(ICR)is the most frequently performed procedure for treating CD.Addressing anastomotic leak(AL)remains a critical focus in the perioperative and postoperative care of CD patients.A research study published in the World Journal of Gastrointestinal Surgery by Cwaliński et al included 77 individuals who had open ICR and primary stapled anastomosis to assess the risk factors linked to anastomotic insufficiency.At present,research on anastomotic insufficiency has focused on AL.Therefore,this editorial mainly analyzes the current risk factors linked to AL after ICR and discusses potential prevention strategies.We comprehensively consider risk factors such as body weight,medication use,surgical history,smoking,penetrating behaviour,and albumin levels to stratify patient risk.Based on recent research insights,we propose that individualized surgical timing,approaches,and techniques should be selected according to the patient's risk level.
文摘Post-esophagectomy anastomotic leak(AL)is a severe complication following esophagectomy,contributing to increased morbidity,prolonged hospitalization,and a significant risk of mortality.Endoscopic vacuum-assisted closure(EndoVac)has emerged as a promising first-line treatment,offering a highly effective approach for managing post-esophagectomy AL.EndoVac therapy utilizes continuous negative pressure within the esophageal lumen or mediastinal cavity,promoting granulation tissue formation,accelerating wound healing,and enhancing AL closure rates.Compared to stenting,EndoVac provides distinct advantages,including superior adaptability to varying leak sizes and locations,enhanced secretion drainage,and lower rates of reintervention.Clinical studies have demonstrated higher success rates,decreased post-intervention complications,and shorter hospital stays.Despite its advantages,challenges persist in patient selection,procedural expertise,and accessibility.EndoVac application requires experienced endoscopic teams and multidisciplinary expertise,which is best achieved in high-volume centers with specialized care.Variability in EndoVac protocols necessitate further refinement and standardization to optimize treatment outcomes.The integration of EndoVac into standardized treatment guidelines holds promise for improving patient outcomes and redefining the management approach for this challenging postoperative complication.
基金Supported by the National Key Research and Development Program,No.2023YFC2307001the National Natural Science Foundation of China,No.82170570,No.82270698,and No.82470679.
文摘BACKGROUND Endoscopic ultrasound-guided biliary drainage,including endoscopic ultrasoundguided choledochoduodenostomy and endoscopic ultrasound-guided hepatogastrostomy(EUS-HGS),is an efficacious alternative to endoscopic retrograde cholangiopancreatography and its common complications are bile leak,infection,stent migration and bleeding.Here,we report an atypical case of a patient who developed unexplained dark green urine after receiving EUS-HGS,which we suspected to be caused by an abnormal biliary-vascular fistula.CASE SUMMARY A 76-year-old woman diagnosed with pancreatic adenocarcinoma received EUSHGS for relieving jaundice.The patient reported abdominal pain and chest tightness after the operation,with difficulty in urinating.X-ray suggested rightsided pleural effusion and dark green pleural effusion was drained out.However,the patient also developed dark green urine,which appeared everyday afternoon and disappeared automatically after intravenous treatment.The previous pleural effusion disappeared after one week,but later the patient showed an increase of ascites,and the lesions were compartmentalized and encapsulated internally.CONCLUSION Postoperative surveillance after EUS-HGS must be emphasized to check for in order to prevent severe and hidden complications.
