There are lots of researches on fixture layout optimization for large thin-walled parts.Current researches focus on the positioning problem,i.e.,optimizing the positions of a constant number of fixtures.However,how to...There are lots of researches on fixture layout optimization for large thin-walled parts.Current researches focus on the positioning problem,i.e.,optimizing the positions of a constant number of fixtures.However,how to determine the number of fixtures is ignored.In most cases,the number of fixtures located on large thin-walled parts is determined based on engineering experience,which leads to huge fixture number and extra waste.Therefore,this paper constructs an optimization model to minimize the number of fixtures.The constraints are set in the optimization model to ensure that the part deformation is within the surface profile tolerance.In addition,the assembly gap between two parts is also controlled.To conduct the optimization,this paper develops an improved particle swarm optimization(IPSO)algorithm by integrating the shrinkage factor and adaptive inertia weight.In the algorithm,particles are encoded according to the fixture position.Each dimension of the particle is assigned to a sub-region by constraining the optional position range of each fixture to improve the optimization efficiency.Finally,a case study on ship curved panel assembly is provided to prove that our method can optimize the number of fixtures while meeting the assembly quality requirements.This research proposes a method to optimize the number of fixtures,which can reduce the number of fixtures and achieve deformation control at the same time.展开更多
An increasing number of researchers have researched fixture layout optimization for thin-walled part assembly during the past decades.However,few papers systematically review these researches.By analyzing existing lit...An increasing number of researchers have researched fixture layout optimization for thin-walled part assembly during the past decades.However,few papers systematically review these researches.By analyzing existing literature,this paper summarizes the process of fixture layout optimization and the methods applied.The process of optimization is made up of optimization objective setting,assembly variation/deformation modeling,and fixture layout optimization.This paper makes a review of the fixture layout for thin-walled parts according to these three steps.First,two different kinds of optimization objectives are introduced.Researchers usually consider in-plane variations or out-of-plane deformations when designing objectives.Then,modeling methods for assembly variation and deformation are divided into two categories:Mechanism-based and data-based methods.Several common methods are discussed respectively.After that,optimization algorithms are reviewed systematically.There are two kinds of optimization algorithms:Traditional nonlinear programming and heuristic algorithms.Finally,discussions on the current situation are provided.The research direction of fixture layout optimization in the future is discussed from three aspects:Objective setting,improving modeling accuracy and optimization algorithms.Also,a new research point for fixture layout optimization is discussed.This paper systematically reviews the research on fixture layout optimization for thin-walled parts,and provides a reference for future research in this field.展开更多
Lightweight thin-walled structures with lattice infill are widely desired in satellite for their high stiffness-to-weight ratio and superior buckling strength resulting fromthe sandwich effect.Such structures can be f...Lightweight thin-walled structures with lattice infill are widely desired in satellite for their high stiffness-to-weight ratio and superior buckling strength resulting fromthe sandwich effect.Such structures can be fabricated bymetallic additive manufacturing technique,such as selective laser melting(SLM).However,the maximum dimensions of actual structures are usually in a sub-meter scale,which results in restrictions on their appliance in aerospace and other fields.In this work,a meter-scale thin-walled structure with lattice infill is designed for the fuel tank supporting component of the satellite by integrating a self-supporting lattice into the thickness optimization of the thin-wall.The designed structure is fabricated by SLM of AlSi10Mg and cold metal transfer welding technique.Quasi-static mechanical tests and vibration tests are both conducted to verify the mechanical strength of the designed large-scale lattice thin-walled structure.The experimental results indicate that themeter-scale thin-walled structure with lattice infill could meet the dimension and lightweight requirements of most spacecrafts.展开更多
As critical components of aircraft skins and rocket fuel storage tank shells,large thin-walled workpieces are susceptible to vibration and deformation during machining due to their weak local stiffness.To address thes...As critical components of aircraft skins and rocket fuel storage tank shells,large thin-walled workpieces are susceptible to vibration and deformation during machining due to their weak local stiffness.To address these challenges,we propose a novel tunable electromagnetic semi-active dynamic vibration absorber(ESADVA),which integrates with a magnetic suction follower to form a followed ESADVA(follow-ESADVA)for mirror milling.This system combines a tunable magnet oscillator with a follower,enabling real-time vibration absorption and condition feedback throughout the milling process.Additionally,the device supports self-sensing and frequency adjustment by providing feedback to a linear actuator,which alters the distance between magnets.This resolves the traditional issue of being unable to directly monitor vibration at the machining point due to space constraints and tool interference.The frequency shift characteristics and vibration absorption performance are comprehensively investigated.Theoretical and experimental results demonstrate that the prototyped follow-ESADVA achieves frequency synchronization with the milling tool,resulting in a vibration suppression rate of approximately 47.57%.Moreover,the roughness of the machined surface decreases by18.95%,significantly enhancing the surface quality.The results of this work pave the way for higher-quality machined surfaces and a more stable mirror milling process.展开更多
Pitting corrosion is harmful during bridge construction,which will lead to uneven roughness of steel surfaces and reduce the thickness of steel.Hence,the effect of pitting corrosion on the mechanical properties of col...Pitting corrosion is harmful during bridge construction,which will lead to uneven roughness of steel surfaces and reduce the thickness of steel.Hence,the effect of pitting corrosion on the mechanical properties of cold-formed thin-walled steel stub columns is studied,and the empirical formulas are established through regression fitting to predict the ultimate load of web and flange under pitting corrosion.In detail,the failure modes and load-displacement curves of specimens with different locations,area ratios,and depths are obtained through a large number of non-linear finite element analysis.As for the specimens with pitting corrosion on the web,all the specimens are subject to local buckling failure,and the failure mode will not change with pitting corrosion,but the failure location will change with pitting corrosion location;the size,location,and area ratio of pitting corrosion have little influence on the ultimate load of cold-formed thin-walled steel short columns,but the loss rate of pitting corrosion section area has a greater impact on the ultimate bearing capacity.As for the specimen with flange pitting corrosion,the location and area ratio of pitting corrosion have less influence on the ultimate load of cold-formed thin-walled steel short columns,and the section area loss rate has greater influence on the ultimate bearing capacity;the impact of web pitting corrosion on the ultimate load is greater than that of flange pitting corrosion under the same condition of pitting corrosion section area.The prediction formulas of limit load which are suitable for pitting corrosion of web and flange are established,which can provide a reference for performance evaluation of corroded cold-formed thin-walled steel.展开更多
This paper develops a new numerical framework for modeⅢcrack problems of thin-walled structures by integrating multiple advanced techniques in the boundary element literature.The details of special crack-tip elements...This paper develops a new numerical framework for modeⅢcrack problems of thin-walled structures by integrating multiple advanced techniques in the boundary element literature.The details of special crack-tip elements for displacement and stress are derived.An exponential transformation technique is introduced to accurately calculate the nearly singular integral,which is the key task of the boundary element simulation of thin-walled structures.Three numerical experiments with different types of cracks are provided to verify the performance of the present numerical framework.Numerical results demonstrate that the present scheme is valid for modeⅢcrack problems of thin-walled structures with the thickness-to-length ratio in the microscale,even nanoscale,regime.展开更多
Percutaneous coronary interventions have progressed through the era of plain balloon dilation, bare-metal stent insertion to drug-eluting stent treatment, which has significantly reduced the acute occlusion and resten...Percutaneous coronary interventions have progressed through the era of plain balloon dilation, bare-metal stent insertion to drug-eluting stent treatment, which has significantly reduced the acute occlusion and restenosis rates of target vessels and improved patient prognosis, making drug-eluting stents the mainstream interventional treatment for coronary artery disease. In recent years, drug-coated balloons(DCBs) have become a new treatment strategy for coronary artery disease, and the drugs used in the coating and the coating technology have progressed in the past years. Without permanent implant, a DCB delivers antiproliferative drugs rapidly and uniformly into the vessel wall via the excipient during a single balloon dilation. Many evidence suggests that DCB angioplasty is an effective measure for dealing with in-stent restenosis and de novo lesions in small coronary vessels.As more clinical studies are published, new evidence is emerging for the use of DCB angioplasty in a wide range of coronary diseases, and the indications are expanding internationally. Based on the latest research from China and elsewhere, the Expert Writing Committee of the Chinese Expert Consensus on Clinical Applications of Drug-Coated Balloon has updated the previous DCB consensus after evidence-based discussions and meetings in terms of adequate preparation of in-stent restenosis lesions, expansion of the indications for coronary de novo lesions, and precise guidance of DCB treatment by intravascular imaging and functional evaluation.展开更多
The application of continuous natural fibers as reinforcement in composite thin-walled structures offers a feasible approach to achieve light weight and high strength while remaining environmentally friendly.In additi...The application of continuous natural fibers as reinforcement in composite thin-walled structures offers a feasible approach to achieve light weight and high strength while remaining environmentally friendly.In addition,additive manufacturing technology provides a favorable process foundation for its realization.In this study,the printability and energy absorption properties of 3D printed continuous fiber reinforced thin-walled structures with different configurations were investigated.The results suggested that a low printing speed and a proper layer thickness would mitigate the printing defects within the structures.The printing geometry accuracy of the structures could be further improved by rounding the sharp corners with appropriate radii.This study successfully fabricated structures with vari-ous configurations characterized by high geometric accuracy through printing parameters optimization and path smoothing.Moreover,the compressive property and energy absorption characteristics of the structures under quasi-static axial compression were evaluated and compared.It was found that all studied thin-walled structures exhibited progressive folding deformation patterns during compression.In particular,energy absorption process was achieved through the combined damage modes of plastic deformation,fiber pullout and delamination.Furthermore,the com-parison results showed that the hexagonal structure exhibited the best energy absorption performance.The study revealed the structure-mechanical property relationship of 3D printed continuous fiber reinforced composite thin-walled structures through the analysis of multiscale failure characteristics and load response,which is valuable for broadening their applications.展开更多
Aortic stenosis(AS)stands out as the most prevalent individual valvular defect globally.The onset and progression of AS mirror an active process akin to atherosclerosis,and the traditional triad of symptoms includes c...Aortic stenosis(AS)stands out as the most prevalent individual valvular defect globally.The onset and progression of AS mirror an active process akin to atherosclerosis,and the traditional triad of symptoms includes chest pain,breathlessness,and loss of consciousness.Prognosis takes a significant downturn when symptoms manifest,with mortality reaching approximately 50%-85% within the subsequent 5 years after symptom onset.展开更多
The incidence of acute myocardial infarction (AMI) is increasing year by year, which seriously endangers human health around the world. The preferred treatment strategy for AMI patients is the use of drug-eluting sten...The incidence of acute myocardial infarction (AMI) is increasing year by year, which seriously endangers human health around the world. The preferred treatment strategy for AMI patients is the use of drug-eluting stents (DES), as there is ample evidence to suggest that stent implantation can reduce major adverse cardiovascular events (MACEs). With the application of drug-coated balloons (DCBs) and the enhancement of the concept of interventional without implantation, the question is whether DCBs can be safely and effectively used in patients with AMI? The purpose of this study was to investigate the safety and effectiveness of DCBs in the treatment of AMI. A retrospective review of clinical data was conducted on 55 AMI patients who underwent primary percutaneous coronary intervention (PCI) from January 2020 to December 2021. Of these patients, 25 were treated with DCBs and 30 were treated with DESs. Optical coherence tomography (OCT) was used to measure the minimum lumen diameter, lumen stenosis, and coronary artery dissection before and after surgery, and angina pectoris attacks and various MACEs were recorded at 1, 6, and 12 months after surgery. The results showed that there were no significant differences in clinical baseline data between the two groups. However, the minimum lumen diameter of the DCB group immediately after the operation was smaller than that of the DES group, and the stenosis degree of the lumen in the DCB group was higher than that in the DES group. The incidence of coronary artery dissection in the DCB group was significantly higher than that in the DES group, but the majority of them were type B. At 1, 6, and 12 months after treatment, there was no significant difference in the occurrence of MACEs between the two groups. In conclusion, DCBs is a safe and effective treatment for AMI. However, the incidence of coronary artery dissection in DCB patients is higher than that in DES patients, but the majority of them are type B. .展开更多
In machining processes,chatter vibrations are always regarded as one of the major limitations for production quality and efficiency.Accurate and timely monitoring of chatter is helpful to maintain stable machining ope...In machining processes,chatter vibrations are always regarded as one of the major limitations for production quality and efficiency.Accurate and timely monitoring of chatter is helpful to maintain stable machining operations.At present,most chatter monitoring methods are based on the energy level at specified chatter frequencies or frequency bands.However,the spectral features of chatter could change during machining operations due to complexity and time-varying dynamics of the physical machining process.The purpose of this paper is to investigate the time-varying chatter features in turning of thin-walled tubular workpieces from the perspective of entropy.The airborne acoustics was selected as the source of information for machining condition monitoring.First,corresponding to the distinguishing surface topographies relevant to machining conditions,the features of the sound signal emitted during turning of the thin-walled cylindrical workpieces were extracted using the spectral analysis and wavelet packet transform,respectively.It was shown that the dominant vibration frequency as well as the energy distribution could shift with the transition of the machining status.After that,two relative entropy indicators based on the spectrum and the wavelet packet energy were constructed to identify chattering events in turning of the thin-walled tubes.The experimental results demonstrate that the proposed indicators could accurately reflect the transition of machining conditions with high sensitivity and robustness in comparison with the traditional FFT-based methods.The achievement of this study lays the foundations of the online chatter monitoring and control technique for turning of the thin-walled tubular workpieces.展开更多
The X-ray sources of the universe are extraterrestrial in nature which emit X-ray photons.The closest strong X-ray source is the Sun,which is followed by various compact sources such as neutron stars,black holes,the C...The X-ray sources of the universe are extraterrestrial in nature which emit X-ray photons.The closest strong X-ray source is the Sun,which is followed by various compact sources such as neutron stars,black holes,the Crab pulsar,etc.In this paper,we analyze the data received from several low-cost lightweight meteorological balloon-borne missions launched by the Indian Centre for Space Physics.Our main interest is to study the variation of the vertical intensity of secondary cosmic rays,the detection of strong X-ray sources,and their spectra in the energy band of^(1)0–80 keV during the complete flights.Due to the lack of an onboard pointing system,low exposure time,achieving a maximum altitude of only~42 km,and freely rotating the payload about its axis,we modeled the background radiation flux for the X-ray detector using physical assumptions.We also present the source detection method,observation of the pulsation of the Crab(^(3)3 Hz),and spectra of some sources such as the quiet Sun and the Crab pulsar.展开更多
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 rec...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.展开更多
BACKGROUND:Resuscitative endovascular balloon occlusion of the aorta(REBOA)can temporarily control traumatic bleeding.However,its prolonged use potentially leads to ischemia-reperfusion injury(IRI).Partial REBOA(pREBO...BACKGROUND:Resuscitative endovascular balloon occlusion of the aorta(REBOA)can temporarily control traumatic bleeding.However,its prolonged use potentially leads to ischemia-reperfusion injury(IRI).Partial REBOA(pREBOA)can alleviate ischemic burden;however,its security and eff ectiveness prior to operative hemorrhage control remains unknown.Hence,we aimed to estimate the effi cacy of pREBOA in a swine model of liver injury using an experimental sliding-chamber ballistic gun.METHODS:Twenty Landrace pigs were randomized into control(no aortic occlusion)(n=5),intervention with complete REBOA(cREBOA)(n=5),continuous pREBOA(C-pREBOA)(n=5),and sequential pREBOA(S-pREBOA)(n=5)groups.In the cREBOA and C-pREBOA groups,the balloon was inflated for 60 min.The hemodynamic and laboratory values were compared at various observation time points.Tissue samples immediately after animal euthanasia from the myocardium,liver,kidneys,and duodenum were collected for histological assessment using hematoxylin and eosin staining.RESULTS:Compared with the control group,the survival rate of the REBOA groups was prominently improved(all P<0.05).The total volume of blood loss was markedly lower in the cREBOA group(493.14±127.31 mL)compared with other groups(P<0.01).The pH was significantly lower at 180 min in the cREBOA and S-pREBOA groups(P<0.05).At 120 min,the S-pREBOA group showed higher alanine aminotransferase(P<0.05)but lower blood urea nitrogen compared with the cREBOA group(P<0.05).CONCLUSION:In this trauma model with liver injury,a 60-minute pREBOA resulted in improved survival rate and was effective in maintaining reliable aortic pressure,despite persistent hemorrhage.Extended tolerance time for aortic occlusion in Zone I for non-compressible torso hemorrhage was feasible with both continuous partial and sequential partial measures,and the significant improvement in the severity of acidosis and distal organ injury was observed in the sequential pREBOA.展开更多
BACKGROUND Over one-third of Americans carry the diagnosis of obesity,many also with obesity-related comorbidities.This can place patients at increased risk of operative and postoperative complications.The intragastri...BACKGROUND Over one-third of Americans carry the diagnosis of obesity,many also with obesity-related comorbidities.This can place patients at increased risk of operative and postoperative complications.The intragastric balloon has been shown to aid in minor weight loss,however its weight recidivism in patients requiring short interval weight loss has not been well studied.AIM To evaluate weight loss,ability to undergo successful elective surgery after intragastric balloon placement,and weight management after balloon removal.METHODS This study is a retrospective review of patients in a single academic institution undergoing intragastric balloon placement from 2019-2023 to aid in weight loss prior to undergoing elective surgery.Clinical outcomes including weight loss,duration of balloon placement,successful elective surgery,weight regain postballoon and post-procedure complications were assessed.Exclusion criteria included those with balloon in place at time of study.RESULTS Thirty-three patients completed intragastric balloon therapy from 2019-2023 as a bridge to elective surgery.All patients were required to participate in a 12-month weight management program to be eligible for balloon therapy.Elective surgeries included incisional hernia repair,umbilical hernia repair,inguinal hernia repair,and knee and hip replacements.The average age at placement was 53 years±11 years,majority(91%)were male.The average duration of intragastric balloon therapy was 186 days±41 days.The average weight loss was 14.0 kg±7.4 kg and with an average percent excess body weight loss of 30.0%(7.9%-73.6%).Over half of the patients(52.0%)achieved the goal of 30-50 lbs(14-22 kg)weight loss.Twenty-one patients(64%)underwent their intended elective surgery,2 patients(6%)deferred surgery due to symptom relief with weight loss alone.Twenty-one of the patients(64%)have documented weights in 3 months after balloon removal,in these patients the majority(76%)gained weight after balloon removed.In patients with weight regain at 3 months,they averaged 5.8 kg after balloon removal in the first 3 months,this averaged 58.4%weight regain of the initial weight lost.CONCLUSION Intragastric balloon placement is an option for short-term weight management,as a bridge to elective surgery in patients with body mass index(BMI)>35.Patients lost an average of 14 kg with the balloon,allowing two-thirds of patients to undergo elective surgery at a healthy BMI.However,most patients regained an average of 58%of the original weight lost after balloon removal.The intragastric balloon successfully serves as a tool for rapid weight loss,though patients must be educated on the risks including weight regain.展开更多
BACKGROUND Intracranial arterial narrowing is a significant factor leading to brief episodes of reduced blood flow to the brain,known as transient ischemic attacks,or fullblown strokes.While atherosclerosis is commonl...BACKGROUND Intracranial arterial narrowing is a significant factor leading to brief episodes of reduced blood flow to the brain,known as transient ischemic attacks,or fullblown strokes.While atherosclerosis is commonly associated with intracranial arterial narrowing,it is frequently of a non-atherosclerotic nature in younger patients.CASE SUMMARY Here,we present the case of a young stroke patient with narrowing of the middle cerebral artery(MCA),characterized as non-atherosclerotic lesions,who experienced an ischemic stroke despite receiving standard drug therapy.The patient underwent digital subtraction angiography(DSA)to assess the entire network of blood vessels in the brain,revealing significant narrowing(approximately 80%)in the M1 segment of the right MCA.Subsequently,the patient underwent Drug-Coated Balloon Angioplasty to treat the stenosis in the right MCA's M1 segment.Follow-up DSA confirmed the resolution of stenosis in this segment.Although the remaining branches showed satisfactory blood flow,the vessel wall exhibited irregularities.A review of DSA conducted six months later showed no evident stenosis in the right MCA,with a smooth vessel wall.CONCLUSION The use of drug-coated balloon angioplasty demonstrated favorable outcomes in repairing and reshaping the blood vessel wall in young patients.Therefore,it may be considered a promising treatment option for similar cases.展开更多
BACKGROUND Endoscopic retrograde cholangiopancreatography(ERCP),with its clinical ad-vantages of less trauma and faster recovery,has become the primary treatment for choledocholithiasis.AIM To investigate the effects ...BACKGROUND Endoscopic retrograde cholangiopancreatography(ERCP),with its clinical ad-vantages of less trauma and faster recovery,has become the primary treatment for choledocholithiasis.AIM To investigate the effects of different ERCP procedures on the sphincter of Oddi.METHODS The clinical data of 91 patients who underwent ERCP at Yixing Hospital of Traditional Chinese Medicine between February 2018 and February 2021 were analyzed retrospectively.The patients were divided into endoscopic sphinc-terotomy(EST,n=24)and endoscopic papillary balloon dilation(EPBD,n=67)groups.The duration of operation,pancreatic development,pancreatic sphinc-terotomy,intubation difficulties,stone recurrence,and incidence of reflux cho-langitis and cholecystitis were statistically analyzed in patients with a history of choledocholithiasis,pancreatitis,and Oddi sphincter dysfunction in the EST and EPBD groups.RESULTS Differences in hypertension,diabetes,increased bilirubin,small diameter of the common bile duct,or ampullary diverticulum between the two groups were not significant.Statistically significant differences were observed between the two groups concerning sex and age(<60 years).Patients with a history of choledocholithiasis,pancreatitis,and Oddi sphincter dysfunction were higher in the EST group than in the EPBD group.The number of cases of pancreatic development,pancreatic duct sphincterotomy,and difficult intubation were higher in the EST group than in the EPBD group.The number of Oddi’s sphincter manometries,ERCP surgical outcomes,and guidewires entering the pancreatic duct several times in EST group were lower than those in the EPBD group.The numbers of stone recurrences,reflux cholangitis,and cholecystitis were higher in the EST group than in the EPBD group.CONCLUSION In summary,common bile duct stones,pancreatitis history,and multiple guided wire introductions into the pancreatic duct are independent risk factors for EST and EPBD.Based on this evidence,this study can provide actionable insights for clinicians and researchers.展开更多
BACKGROUND Incomplete congenital duodenal obstruction(ICDO)is caused by a congenitally perforated duodenal web(CPDW).Currently,only six cases of balloon dilatation of the PDW in newborns have been described.AIM To pre...BACKGROUND Incomplete congenital duodenal obstruction(ICDO)is caused by a congenitally perforated duodenal web(CPDW).Currently,only six cases of balloon dilatation of the PDW in newborns have been described.AIM To present our experience of balloon dilatation of a perforated duodenal memb-rane in newborns with ICDO.METHODS Five newborns who underwent balloon dilatation of the CPDW along a prein-stalled guidewire between 2021 and 2023 were included.Nineteen newborns diagnosed with ICDO who underwent laparotomy were included in the control group.RESULTS In all cases,good anatomical and clinical results were obtained.In three cases,a follow-up study was conducted after 1 year.The average time to start enteral feeding per os was significantly earlier in the study group(4.4 d)than in the laparotomic group(21.2 days;P<0.0001).The time spent by patients in the intensive care unit and hospital after balloon dilatation was also significantly shorter.We determined the selection criteria for possible and effective CPDW balloon dilatation in newborns as follows:(1)Presence of dynamic radiographic signs of the passage of a radiopaque substance beyond the zone of narrowing or radiographic signs of pneumatisation of the duodenum and small bowel distal to the web;(2)presence of endoscopic signs of CPDW;(3)successful cannulation with a guidewire performed parallel to the endoscope,with holes in the congenital duodenal web;and(4)successful positioning of the balloon performed along a freestanding guidewire on the web.CONCLUSION Strictly following selection criteria for newborns with ICDO caused by CPDW ensures that endoscopic balloon dilatation using a pre-installed guidewire is safe and effective and shows good 1-year follow-up results.展开更多
BACKGROUND The incidence of cholelithiasis has been on the rise in recent years,but the choice of procedure is controversial.AIM To investigate the efficacy of laparoscopic cholecystectomy(LC)combined with endoscopic ...BACKGROUND The incidence of cholelithiasis has been on the rise in recent years,but the choice of procedure is controversial.AIM To investigate the efficacy of laparoscopic cholecystectomy(LC)combined with endoscopic papillary balloon dilation(EPBD)in patients with gallbladder stones(GS)with common bile duct stones(CBDS).METHODS The clinical data of 102 patients with GS combined with CBDS were selected for retrospective analysis and divided into either an LC+EPBD group(n=50)or an LC+endoscopic sphincterotomy(EST)group(n=52)according to surgical methods.Surgery-related indexes,postoperative recovery,postoperative complications,and expression levels of inflammatory response indexes were compared between the two groups.RESULTS Total surgical time,stone free rate,rate of conversion to laparotomy,and successful stone extraction rate did not differ significantly between the LC+EPBD group and LC+EST group.Intraoperative hemorrhage,time to ambulation,and length of hospitalization in the LC+EPBD group were lower than those of the LC+EST group(P<0.05).The rate of total complications of the two groups was 9.80%and 17.65%,respectively,and the difference was not statistically significant.No serious complications occurred in either group.At 48 h postoperatively,the expression levels of interleukin-6,tumor necrosis factor-α,high-sensitivity Creactive protein,and procalcitonin were lower in the LC+EPBD group than in the LC+EST group(P<0.05).At 3 d postoperatively,the expression levels of aspartate transaminase,alanine transaminase,and total bilirubin were lower in the LC+EPBD group than in the LC+EST group(P<0.05).CONCLUSION LC combined with EPBD and LC combined with EST are both effective procedures for the treatment of GS with CBDS,in which LC combined with EPBD is beneficial to shorten the patient’s hospitalization time,reduce the magnitude of elevated inflammatory response indexes,and promote postoperative recovery.展开更多
BACKGROUND The combination of acute ST-segment elevation myocardial infarction(STEMI)and gastric ulcers poses a challenge to primary percutaneous coronary intervention(PPCI),particularly for young patients.The role of...BACKGROUND The combination of acute ST-segment elevation myocardial infarction(STEMI)and gastric ulcers poses a challenge to primary percutaneous coronary intervention(PPCI),particularly for young patients.The role of drug-coated balloons(DCBs)in the treatment of de novo coronary artery lesions in large vessels remains unclear,especially for patients with STEMI.Our strategy is to implement drug balloon angioplasty following the intracoronary administration of low-dose prourokinase and adequate pre-expansion.CASE SUMMARY A 54-year-old male patient presented to the emergency department due to chest pain on June 24,2019.Within the first 3 minutes of the initial assessment in the emergency room,the electrocardiogram(ECG)showed significant changes.There was atrial fibrillation with ST-segment elevation.Subsequently,atrial fibrillation terminated spontaneously and reverted to sinus rhythm.Soon after,the patient experienced syncope.The ECG revealed torsades de pointes ventricular tachycardia.A few seconds later,it returned to sinus rhythm.High-sensitivity tropon in I was normal.The diagnosis was acute STEMI.Emergency coronary angiography revealed subtotal occlusion with thrombus formation in the proximal segment of the left anterior descending artery.Considering the patient's age and history of peptic ulcer disease,after the intracoronary injection of prourokinase,percutaneous transluminal coronary angioplasty and cutting balloon angioplasty were conducted for thorough preconditioning,and paclitaxel drug-eluting balloon angioplasty was performed without any stents,achieving favorable outcomes.CONCLUSION A PPCI without stents may be a viable treatment strategy for select patients with STEMI,and further research is warranted.展开更多
基金Supported by National Natural Science Foundation of China(Grant No.52005371)Shanghai Pujiang Program of China(Grant No.2020PJD071)+1 种基金Shanghai Municipal Natural Science Foundation of China(Grant No.22ZR1463900)Fundamental Research Funds for the Central Universities of China.
文摘There are lots of researches on fixture layout optimization for large thin-walled parts.Current researches focus on the positioning problem,i.e.,optimizing the positions of a constant number of fixtures.However,how to determine the number of fixtures is ignored.In most cases,the number of fixtures located on large thin-walled parts is determined based on engineering experience,which leads to huge fixture number and extra waste.Therefore,this paper constructs an optimization model to minimize the number of fixtures.The constraints are set in the optimization model to ensure that the part deformation is within the surface profile tolerance.In addition,the assembly gap between two parts is also controlled.To conduct the optimization,this paper develops an improved particle swarm optimization(IPSO)algorithm by integrating the shrinkage factor and adaptive inertia weight.In the algorithm,particles are encoded according to the fixture position.Each dimension of the particle is assigned to a sub-region by constraining the optional position range of each fixture to improve the optimization efficiency.Finally,a case study on ship curved panel assembly is provided to prove that our method can optimize the number of fixtures while meeting the assembly quality requirements.This research proposes a method to optimize the number of fixtures,which can reduce the number of fixtures and achieve deformation control at the same time.
基金Supported by National Natural Science Foundation of China(Grant No.52005371)Shanghai Municipal Natural Science Foundation of China(Grant No.22ZR1463900)+1 种基金Fundamental Research Funds for the Central Universities of China(Grant No.22120220649)State Key Laboratory of Mechanical System and Vibration of China(Grant No.MSV202318).
文摘An increasing number of researchers have researched fixture layout optimization for thin-walled part assembly during the past decades.However,few papers systematically review these researches.By analyzing existing literature,this paper summarizes the process of fixture layout optimization and the methods applied.The process of optimization is made up of optimization objective setting,assembly variation/deformation modeling,and fixture layout optimization.This paper makes a review of the fixture layout for thin-walled parts according to these three steps.First,two different kinds of optimization objectives are introduced.Researchers usually consider in-plane variations or out-of-plane deformations when designing objectives.Then,modeling methods for assembly variation and deformation are divided into two categories:Mechanism-based and data-based methods.Several common methods are discussed respectively.After that,optimization algorithms are reviewed systematically.There are two kinds of optimization algorithms:Traditional nonlinear programming and heuristic algorithms.Finally,discussions on the current situation are provided.The research direction of fixture layout optimization in the future is discussed from three aspects:Objective setting,improving modeling accuracy and optimization algorithms.Also,a new research point for fixture layout optimization is discussed.This paper systematically reviews the research on fixture layout optimization for thin-walled parts,and provides a reference for future research in this field.
基金The authors are grateful for the support by National Key Research and Development Program of China(2021YFF0500300,2020YFB1708300)the National Natural Science Foundation of China(52205280,12172041).
文摘Lightweight thin-walled structures with lattice infill are widely desired in satellite for their high stiffness-to-weight ratio and superior buckling strength resulting fromthe sandwich effect.Such structures can be fabricated bymetallic additive manufacturing technique,such as selective laser melting(SLM).However,the maximum dimensions of actual structures are usually in a sub-meter scale,which results in restrictions on their appliance in aerospace and other fields.In this work,a meter-scale thin-walled structure with lattice infill is designed for the fuel tank supporting component of the satellite by integrating a self-supporting lattice into the thickness optimization of the thin-wall.The designed structure is fabricated by SLM of AlSi10Mg and cold metal transfer welding technique.Quasi-static mechanical tests and vibration tests are both conducted to verify the mechanical strength of the designed large-scale lattice thin-walled structure.The experimental results indicate that themeter-scale thin-walled structure with lattice infill could meet the dimension and lightweight requirements of most spacecrafts.
基金Project supported by the National Natural Science Foundation of China(Nos.12172248,12021002,12302022,and 12132010)the Tianjin Research Program of Application Foundation and Advanced Technology of China(No.22JCQNJC00780)IoT Standards and Application Key Laboratory of the Ministry of Industry and Information Technology of China(No.202306)。
文摘As critical components of aircraft skins and rocket fuel storage tank shells,large thin-walled workpieces are susceptible to vibration and deformation during machining due to their weak local stiffness.To address these challenges,we propose a novel tunable electromagnetic semi-active dynamic vibration absorber(ESADVA),which integrates with a magnetic suction follower to form a followed ESADVA(follow-ESADVA)for mirror milling.This system combines a tunable magnet oscillator with a follower,enabling real-time vibration absorption and condition feedback throughout the milling process.Additionally,the device supports self-sensing and frequency adjustment by providing feedback to a linear actuator,which alters the distance between magnets.This resolves the traditional issue of being unable to directly monitor vibration at the machining point due to space constraints and tool interference.The frequency shift characteristics and vibration absorption performance are comprehensively investigated.Theoretical and experimental results demonstrate that the prototyped follow-ESADVA achieves frequency synchronization with the milling tool,resulting in a vibration suppression rate of approximately 47.57%.Moreover,the roughness of the machined surface decreases by18.95%,significantly enhancing the surface quality.The results of this work pave the way for higher-quality machined surfaces and a more stable mirror milling process.
基金funded by the‘Research Project of the Sucheng to Sihong Section of the Yanluo Expressway-Measurement Technology and Application of Bridge Quality Project Based on UAV Binocular Imaging(No.00-00-JSFW-20230203-029)’,received by H.Z.Wang.
文摘Pitting corrosion is harmful during bridge construction,which will lead to uneven roughness of steel surfaces and reduce the thickness of steel.Hence,the effect of pitting corrosion on the mechanical properties of cold-formed thin-walled steel stub columns is studied,and the empirical formulas are established through regression fitting to predict the ultimate load of web and flange under pitting corrosion.In detail,the failure modes and load-displacement curves of specimens with different locations,area ratios,and depths are obtained through a large number of non-linear finite element analysis.As for the specimens with pitting corrosion on the web,all the specimens are subject to local buckling failure,and the failure mode will not change with pitting corrosion,but the failure location will change with pitting corrosion location;the size,location,and area ratio of pitting corrosion have little influence on the ultimate load of cold-formed thin-walled steel short columns,but the loss rate of pitting corrosion section area has a greater impact on the ultimate bearing capacity.As for the specimen with flange pitting corrosion,the location and area ratio of pitting corrosion have less influence on the ultimate load of cold-formed thin-walled steel short columns,and the section area loss rate has greater influence on the ultimate bearing capacity;the impact of web pitting corrosion on the ultimate load is greater than that of flange pitting corrosion under the same condition of pitting corrosion section area.The prediction formulas of limit load which are suitable for pitting corrosion of web and flange are established,which can provide a reference for performance evaluation of corroded cold-formed thin-walled steel.
基金supported by the National Natural Science Foundation of China(No.11802165)the China Postdoctoral Science Foundation(Grant No.2019M650158).
文摘This paper develops a new numerical framework for modeⅢcrack problems of thin-walled structures by integrating multiple advanced techniques in the boundary element literature.The details of special crack-tip elements for displacement and stress are derived.An exponential transformation technique is introduced to accurately calculate the nearly singular integral,which is the key task of the boundary element simulation of thin-walled structures.Three numerical experiments with different types of cracks are provided to verify the performance of the present numerical framework.Numerical results demonstrate that the present scheme is valid for modeⅢcrack problems of thin-walled structures with the thickness-to-length ratio in the microscale,even nanoscale,regime.
文摘Percutaneous coronary interventions have progressed through the era of plain balloon dilation, bare-metal stent insertion to drug-eluting stent treatment, which has significantly reduced the acute occlusion and restenosis rates of target vessels and improved patient prognosis, making drug-eluting stents the mainstream interventional treatment for coronary artery disease. In recent years, drug-coated balloons(DCBs) have become a new treatment strategy for coronary artery disease, and the drugs used in the coating and the coating technology have progressed in the past years. Without permanent implant, a DCB delivers antiproliferative drugs rapidly and uniformly into the vessel wall via the excipient during a single balloon dilation. Many evidence suggests that DCB angioplasty is an effective measure for dealing with in-stent restenosis and de novo lesions in small coronary vessels.As more clinical studies are published, new evidence is emerging for the use of DCB angioplasty in a wide range of coronary diseases, and the indications are expanding internationally. Based on the latest research from China and elsewhere, the Expert Writing Committee of the Chinese Expert Consensus on Clinical Applications of Drug-Coated Balloon has updated the previous DCB consensus after evidence-based discussions and meetings in terms of adequate preparation of in-stent restenosis lesions, expansion of the indications for coronary de novo lesions, and precise guidance of DCB treatment by intravascular imaging and functional evaluation.
基金Supported by National Natural Science Foundation of China(Grant Nos.51905555,52105523)Hu-Xiang Youth Talent Program of China(Grant No.2020RC3009)Innovation-Driven Project of Central South University of China(Grant No.2019CX017).
文摘The application of continuous natural fibers as reinforcement in composite thin-walled structures offers a feasible approach to achieve light weight and high strength while remaining environmentally friendly.In addition,additive manufacturing technology provides a favorable process foundation for its realization.In this study,the printability and energy absorption properties of 3D printed continuous fiber reinforced thin-walled structures with different configurations were investigated.The results suggested that a low printing speed and a proper layer thickness would mitigate the printing defects within the structures.The printing geometry accuracy of the structures could be further improved by rounding the sharp corners with appropriate radii.This study successfully fabricated structures with vari-ous configurations characterized by high geometric accuracy through printing parameters optimization and path smoothing.Moreover,the compressive property and energy absorption characteristics of the structures under quasi-static axial compression were evaluated and compared.It was found that all studied thin-walled structures exhibited progressive folding deformation patterns during compression.In particular,energy absorption process was achieved through the combined damage modes of plastic deformation,fiber pullout and delamination.Furthermore,the com-parison results showed that the hexagonal structure exhibited the best energy absorption performance.The study revealed the structure-mechanical property relationship of 3D printed continuous fiber reinforced composite thin-walled structures through the analysis of multiscale failure characteristics and load response,which is valuable for broadening their applications.
文摘Aortic stenosis(AS)stands out as the most prevalent individual valvular defect globally.The onset and progression of AS mirror an active process akin to atherosclerosis,and the traditional triad of symptoms includes chest pain,breathlessness,and loss of consciousness.Prognosis takes a significant downturn when symptoms manifest,with mortality reaching approximately 50%-85% within the subsequent 5 years after symptom onset.
文摘The incidence of acute myocardial infarction (AMI) is increasing year by year, which seriously endangers human health around the world. The preferred treatment strategy for AMI patients is the use of drug-eluting stents (DES), as there is ample evidence to suggest that stent implantation can reduce major adverse cardiovascular events (MACEs). With the application of drug-coated balloons (DCBs) and the enhancement of the concept of interventional without implantation, the question is whether DCBs can be safely and effectively used in patients with AMI? The purpose of this study was to investigate the safety and effectiveness of DCBs in the treatment of AMI. A retrospective review of clinical data was conducted on 55 AMI patients who underwent primary percutaneous coronary intervention (PCI) from January 2020 to December 2021. Of these patients, 25 were treated with DCBs and 30 were treated with DESs. Optical coherence tomography (OCT) was used to measure the minimum lumen diameter, lumen stenosis, and coronary artery dissection before and after surgery, and angina pectoris attacks and various MACEs were recorded at 1, 6, and 12 months after surgery. The results showed that there were no significant differences in clinical baseline data between the two groups. However, the minimum lumen diameter of the DCB group immediately after the operation was smaller than that of the DES group, and the stenosis degree of the lumen in the DCB group was higher than that in the DES group. The incidence of coronary artery dissection in the DCB group was significantly higher than that in the DES group, but the majority of them were type B. At 1, 6, and 12 months after treatment, there was no significant difference in the occurrence of MACEs between the two groups. In conclusion, DCBs is a safe and effective treatment for AMI. However, the incidence of coronary artery dissection in DCB patients is higher than that in DES patients, but the majority of them are type B. .
基金The financial support of National Natural Science Foundation of China(Grant Nos.52175108,51805352)is gratefully acknowledgedWe also would like to acknowledge the Key Research and Development Project of Shanxi Province(Grant No.202102010101009).
文摘In machining processes,chatter vibrations are always regarded as one of the major limitations for production quality and efficiency.Accurate and timely monitoring of chatter is helpful to maintain stable machining operations.At present,most chatter monitoring methods are based on the energy level at specified chatter frequencies or frequency bands.However,the spectral features of chatter could change during machining operations due to complexity and time-varying dynamics of the physical machining process.The purpose of this paper is to investigate the time-varying chatter features in turning of thin-walled tubular workpieces from the perspective of entropy.The airborne acoustics was selected as the source of information for machining condition monitoring.First,corresponding to the distinguishing surface topographies relevant to machining conditions,the features of the sound signal emitted during turning of the thin-walled cylindrical workpieces were extracted using the spectral analysis and wavelet packet transform,respectively.It was shown that the dominant vibration frequency as well as the energy distribution could shift with the transition of the machining status.After that,two relative entropy indicators based on the spectrum and the wavelet packet energy were constructed to identify chattering events in turning of the thin-walled tubes.The experimental results demonstrate that the proposed indicators could accurately reflect the transition of machining conditions with high sensitivity and robustness in comparison with the traditional FFT-based methods.The achievement of this study lays the foundations of the online chatter monitoring and control technique for turning of the thin-walled tubular workpieces.
文摘The X-ray sources of the universe are extraterrestrial in nature which emit X-ray photons.The closest strong X-ray source is the Sun,which is followed by various compact sources such as neutron stars,black holes,the Crab pulsar,etc.In this paper,we analyze the data received from several low-cost lightweight meteorological balloon-borne missions launched by the Indian Centre for Space Physics.Our main interest is to study the variation of the vertical intensity of secondary cosmic rays,the detection of strong X-ray sources,and their spectra in the energy band of^(1)0–80 keV during the complete flights.Due to the lack of an onboard pointing system,low exposure time,achieving a maximum altitude of only~42 km,and freely rotating the payload about its axis,we modeled the background radiation flux for the X-ray detector using physical assumptions.We also present the source detection method,observation of the pulsation of the Crab(^(3)3 Hz),and spectra of some sources such as the quiet Sun and the Crab pulsar.
文摘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.
基金supported by military logistics scientific research project(AHJ16J004)。
文摘BACKGROUND:Resuscitative endovascular balloon occlusion of the aorta(REBOA)can temporarily control traumatic bleeding.However,its prolonged use potentially leads to ischemia-reperfusion injury(IRI).Partial REBOA(pREBOA)can alleviate ischemic burden;however,its security and eff ectiveness prior to operative hemorrhage control remains unknown.Hence,we aimed to estimate the effi cacy of pREBOA in a swine model of liver injury using an experimental sliding-chamber ballistic gun.METHODS:Twenty Landrace pigs were randomized into control(no aortic occlusion)(n=5),intervention with complete REBOA(cREBOA)(n=5),continuous pREBOA(C-pREBOA)(n=5),and sequential pREBOA(S-pREBOA)(n=5)groups.In the cREBOA and C-pREBOA groups,the balloon was inflated for 60 min.The hemodynamic and laboratory values were compared at various observation time points.Tissue samples immediately after animal euthanasia from the myocardium,liver,kidneys,and duodenum were collected for histological assessment using hematoxylin and eosin staining.RESULTS:Compared with the control group,the survival rate of the REBOA groups was prominently improved(all P<0.05).The total volume of blood loss was markedly lower in the cREBOA group(493.14±127.31 mL)compared with other groups(P<0.01).The pH was significantly lower at 180 min in the cREBOA and S-pREBOA groups(P<0.05).At 120 min,the S-pREBOA group showed higher alanine aminotransferase(P<0.05)but lower blood urea nitrogen compared with the cREBOA group(P<0.05).CONCLUSION:In this trauma model with liver injury,a 60-minute pREBOA resulted in improved survival rate and was effective in maintaining reliable aortic pressure,despite persistent hemorrhage.Extended tolerance time for aortic occlusion in Zone I for non-compressible torso hemorrhage was feasible with both continuous partial and sequential partial measures,and the significant improvement in the severity of acidosis and distal organ injury was observed in the sequential pREBOA.
文摘BACKGROUND Over one-third of Americans carry the diagnosis of obesity,many also with obesity-related comorbidities.This can place patients at increased risk of operative and postoperative complications.The intragastric balloon has been shown to aid in minor weight loss,however its weight recidivism in patients requiring short interval weight loss has not been well studied.AIM To evaluate weight loss,ability to undergo successful elective surgery after intragastric balloon placement,and weight management after balloon removal.METHODS This study is a retrospective review of patients in a single academic institution undergoing intragastric balloon placement from 2019-2023 to aid in weight loss prior to undergoing elective surgery.Clinical outcomes including weight loss,duration of balloon placement,successful elective surgery,weight regain postballoon and post-procedure complications were assessed.Exclusion criteria included those with balloon in place at time of study.RESULTS Thirty-three patients completed intragastric balloon therapy from 2019-2023 as a bridge to elective surgery.All patients were required to participate in a 12-month weight management program to be eligible for balloon therapy.Elective surgeries included incisional hernia repair,umbilical hernia repair,inguinal hernia repair,and knee and hip replacements.The average age at placement was 53 years±11 years,majority(91%)were male.The average duration of intragastric balloon therapy was 186 days±41 days.The average weight loss was 14.0 kg±7.4 kg and with an average percent excess body weight loss of 30.0%(7.9%-73.6%).Over half of the patients(52.0%)achieved the goal of 30-50 lbs(14-22 kg)weight loss.Twenty-one patients(64%)underwent their intended elective surgery,2 patients(6%)deferred surgery due to symptom relief with weight loss alone.Twenty-one of the patients(64%)have documented weights in 3 months after balloon removal,in these patients the majority(76%)gained weight after balloon removed.In patients with weight regain at 3 months,they averaged 5.8 kg after balloon removal in the first 3 months,this averaged 58.4%weight regain of the initial weight lost.CONCLUSION Intragastric balloon placement is an option for short-term weight management,as a bridge to elective surgery in patients with body mass index(BMI)>35.Patients lost an average of 14 kg with the balloon,allowing two-thirds of patients to undergo elective surgery at a healthy BMI.However,most patients regained an average of 58%of the original weight lost after balloon removal.The intragastric balloon successfully serves as a tool for rapid weight loss,though patients must be educated on the risks including weight regain.
文摘BACKGROUND Intracranial arterial narrowing is a significant factor leading to brief episodes of reduced blood flow to the brain,known as transient ischemic attacks,or fullblown strokes.While atherosclerosis is commonly associated with intracranial arterial narrowing,it is frequently of a non-atherosclerotic nature in younger patients.CASE SUMMARY Here,we present the case of a young stroke patient with narrowing of the middle cerebral artery(MCA),characterized as non-atherosclerotic lesions,who experienced an ischemic stroke despite receiving standard drug therapy.The patient underwent digital subtraction angiography(DSA)to assess the entire network of blood vessels in the brain,revealing significant narrowing(approximately 80%)in the M1 segment of the right MCA.Subsequently,the patient underwent Drug-Coated Balloon Angioplasty to treat the stenosis in the right MCA's M1 segment.Follow-up DSA confirmed the resolution of stenosis in this segment.Although the remaining branches showed satisfactory blood flow,the vessel wall exhibited irregularities.A review of DSA conducted six months later showed no evident stenosis in the right MCA,with a smooth vessel wall.CONCLUSION The use of drug-coated balloon angioplasty demonstrated favorable outcomes in repairing and reshaping the blood vessel wall in young patients.Therefore,it may be considered a promising treatment option for similar cases.
文摘BACKGROUND Endoscopic retrograde cholangiopancreatography(ERCP),with its clinical ad-vantages of less trauma and faster recovery,has become the primary treatment for choledocholithiasis.AIM To investigate the effects of different ERCP procedures on the sphincter of Oddi.METHODS The clinical data of 91 patients who underwent ERCP at Yixing Hospital of Traditional Chinese Medicine between February 2018 and February 2021 were analyzed retrospectively.The patients were divided into endoscopic sphinc-terotomy(EST,n=24)and endoscopic papillary balloon dilation(EPBD,n=67)groups.The duration of operation,pancreatic development,pancreatic sphinc-terotomy,intubation difficulties,stone recurrence,and incidence of reflux cho-langitis and cholecystitis were statistically analyzed in patients with a history of choledocholithiasis,pancreatitis,and Oddi sphincter dysfunction in the EST and EPBD groups.RESULTS Differences in hypertension,diabetes,increased bilirubin,small diameter of the common bile duct,or ampullary diverticulum between the two groups were not significant.Statistically significant differences were observed between the two groups concerning sex and age(<60 years).Patients with a history of choledocholithiasis,pancreatitis,and Oddi sphincter dysfunction were higher in the EST group than in the EPBD group.The number of cases of pancreatic development,pancreatic duct sphincterotomy,and difficult intubation were higher in the EST group than in the EPBD group.The number of Oddi’s sphincter manometries,ERCP surgical outcomes,and guidewires entering the pancreatic duct several times in EST group were lower than those in the EPBD group.The numbers of stone recurrences,reflux cholangitis,and cholecystitis were higher in the EST group than in the EPBD group.CONCLUSION In summary,common bile duct stones,pancreatitis history,and multiple guided wire introductions into the pancreatic duct are independent risk factors for EST and EPBD.Based on this evidence,this study can provide actionable insights for clinicians and researchers.
基金The study was reviewed and approved by the Research Ethics Committee of Republican Scientific and Practical Center of Pediatric Surgery Minsk,Republic of Belarus(Protocol 9 of August 24,2023).
文摘BACKGROUND Incomplete congenital duodenal obstruction(ICDO)is caused by a congenitally perforated duodenal web(CPDW).Currently,only six cases of balloon dilatation of the PDW in newborns have been described.AIM To present our experience of balloon dilatation of a perforated duodenal memb-rane in newborns with ICDO.METHODS Five newborns who underwent balloon dilatation of the CPDW along a prein-stalled guidewire between 2021 and 2023 were included.Nineteen newborns diagnosed with ICDO who underwent laparotomy were included in the control group.RESULTS In all cases,good anatomical and clinical results were obtained.In three cases,a follow-up study was conducted after 1 year.The average time to start enteral feeding per os was significantly earlier in the study group(4.4 d)than in the laparotomic group(21.2 days;P<0.0001).The time spent by patients in the intensive care unit and hospital after balloon dilatation was also significantly shorter.We determined the selection criteria for possible and effective CPDW balloon dilatation in newborns as follows:(1)Presence of dynamic radiographic signs of the passage of a radiopaque substance beyond the zone of narrowing or radiographic signs of pneumatisation of the duodenum and small bowel distal to the web;(2)presence of endoscopic signs of CPDW;(3)successful cannulation with a guidewire performed parallel to the endoscope,with holes in the congenital duodenal web;and(4)successful positioning of the balloon performed along a freestanding guidewire on the web.CONCLUSION Strictly following selection criteria for newborns with ICDO caused by CPDW ensures that endoscopic balloon dilatation using a pre-installed guidewire is safe and effective and shows good 1-year follow-up results.
基金Supported by Qiqihar Science and Technology Plan Joint Guidance Project,No.LHYD-2021058.
文摘BACKGROUND The incidence of cholelithiasis has been on the rise in recent years,but the choice of procedure is controversial.AIM To investigate the efficacy of laparoscopic cholecystectomy(LC)combined with endoscopic papillary balloon dilation(EPBD)in patients with gallbladder stones(GS)with common bile duct stones(CBDS).METHODS The clinical data of 102 patients with GS combined with CBDS were selected for retrospective analysis and divided into either an LC+EPBD group(n=50)or an LC+endoscopic sphincterotomy(EST)group(n=52)according to surgical methods.Surgery-related indexes,postoperative recovery,postoperative complications,and expression levels of inflammatory response indexes were compared between the two groups.RESULTS Total surgical time,stone free rate,rate of conversion to laparotomy,and successful stone extraction rate did not differ significantly between the LC+EPBD group and LC+EST group.Intraoperative hemorrhage,time to ambulation,and length of hospitalization in the LC+EPBD group were lower than those of the LC+EST group(P<0.05).The rate of total complications of the two groups was 9.80%and 17.65%,respectively,and the difference was not statistically significant.No serious complications occurred in either group.At 48 h postoperatively,the expression levels of interleukin-6,tumor necrosis factor-α,high-sensitivity Creactive protein,and procalcitonin were lower in the LC+EPBD group than in the LC+EST group(P<0.05).At 3 d postoperatively,the expression levels of aspartate transaminase,alanine transaminase,and total bilirubin were lower in the LC+EPBD group than in the LC+EST group(P<0.05).CONCLUSION LC combined with EPBD and LC combined with EST are both effective procedures for the treatment of GS with CBDS,in which LC combined with EPBD is beneficial to shorten the patient’s hospitalization time,reduce the magnitude of elevated inflammatory response indexes,and promote postoperative recovery.
基金Supported by Mianyang Health Commission 2019 Scientific Research Encouragement Project,No.201948.
文摘BACKGROUND The combination of acute ST-segment elevation myocardial infarction(STEMI)and gastric ulcers poses a challenge to primary percutaneous coronary intervention(PPCI),particularly for young patients.The role of drug-coated balloons(DCBs)in the treatment of de novo coronary artery lesions in large vessels remains unclear,especially for patients with STEMI.Our strategy is to implement drug balloon angioplasty following the intracoronary administration of low-dose prourokinase and adequate pre-expansion.CASE SUMMARY A 54-year-old male patient presented to the emergency department due to chest pain on June 24,2019.Within the first 3 minutes of the initial assessment in the emergency room,the electrocardiogram(ECG)showed significant changes.There was atrial fibrillation with ST-segment elevation.Subsequently,atrial fibrillation terminated spontaneously and reverted to sinus rhythm.Soon after,the patient experienced syncope.The ECG revealed torsades de pointes ventricular tachycardia.A few seconds later,it returned to sinus rhythm.High-sensitivity tropon in I was normal.The diagnosis was acute STEMI.Emergency coronary angiography revealed subtotal occlusion with thrombus formation in the proximal segment of the left anterior descending artery.Considering the patient's age and history of peptic ulcer disease,after the intracoronary injection of prourokinase,percutaneous transluminal coronary angioplasty and cutting balloon angioplasty were conducted for thorough preconditioning,and paclitaxel drug-eluting balloon angioplasty was performed without any stents,achieving favorable outcomes.CONCLUSION A PPCI without stents may be a viable treatment strategy for select patients with STEMI,and further research is warranted.