A Comparative Study on the Post-Buckling Behavior of Reinforced Thermoplastic Pipes(RTPs)Under External Pressure Considering Progressive Failure

The collapse pressure is a key parameter when RTPs are applied in harsh deep-water environments.To investigate the collapse of RTPs,numerical simulations and hydrostatic pressure tests are conducted.For the numerical simulations,the eigenvalue analysis and Riks analysis are combined,in which the Hashin failure criterion and fracture energy stiffness degradation model are used to simulate the progressive failure of composites,and the“infinite”boundary conditions are applied to eliminate the boundary effects.As for the hydrostatic pressure tests,RTP specimens were placed in a hydrostatic chamber after filled with water.It has been observed that the cross-section of the middle part collapses when it reaches the maximum pressure.The collapse pressure obtained from the numerical simulations agrees well with that in the experiment.Meanwhile,the applicability of NASA SP-8007 formula on the collapse pressure prediction was also discussed.It has a relatively greater difference because of the ignorance of the progressive failure of composites.For the parametric study,it is found that RTPs have much higher first-ply-failure pressure when the winding angles are between 50°and 70°.Besides,the effect of debonding and initial ovality,and the contribution of the liner and coating are also discussed.

White Matter Lesions in Young-Middle Aged Migraineurs with Patent Foreman Ovale: A Case-Control Study

Background:White matter lesion(WML)is common in aging brain and is associated with cognitive impairment and dementia.However,recent studies reported an association between patent foramen ovale(PFO)and WML in migraineurs,especially in young,middle-aged migraineurs.Our retrospective,case-control study aims to describe the clinical characteristics of WML in this population and to explore potential risk factors.Methods:226 patients with migraine and PFO were consecutively initially screened.Relevant factors were selected by the least absolute shrinkage and selection operator(LASSO)regression and multivariable logistic regression model.A Nomogram was employed to visualize the prediction model conveniently.The discrimination and calibration abilities were evaluated using the Receiver Operating Characteristic(ROC)curve,the Hosmer-Lemeshow test,and calibration curves.Results:One hundred and nineteen participants were ultimately enrolled in our study,with a median age of 36.9±12.7 years and 80.7%of females.Brain magnetic resonance imaging MRI showed 67(56.3%)patients had WML,whereas 52(43.7%)patients were categorized into the non-WML group.LASSO regression screened out potential variables and subsequent multivariate analysisfinally identified age,mean platelet volume,andfibri-nogen(FIB)as independent predictive factors of WML.The area under the ROC curve(AUC)was 0.807.Hos-mer-Lemeshow test and calibration curve verified a consistency between the predicted and actual probability.Conclusion:The predictive nomogram established and validated in our study may assist clinicians in screening WML among young middle-aged migraineurs with PFO and developing individualized preventive and treatment strategies.

Multiple paradoxical embolisms caused by central venous catheter thrombus passing through a patent foramen ovale: A case report

BACKGROUND To date,this is the first case of a paradoxical embolism(PDE)that concurrently manifested in the coronary and lower limb arteries and was secondary to a central venous catheter(CVC)thrombus via a patent foramen ovale(PFO).CASE SUMMARY Here,we report a case of simultaneous coronary and lower limb artery embolism in a PFO patient carrier of a CVC.The patient presented to the hospital with acute chest pain and lower limb fatigue.Doppler ultrasound showed a large thrombus in the right internal jugular vein,precisely at the tip of the CVC.Transthoracic and transesophageal echocardiography confirmed the existence of a PFO,with inducible right-to-left shunting by the Valsalva maneuver.The patient was administered an extended course of anticoagulation therapy,and then the CVC was successfully removed.Percutaneous PFO closure was not undertaken.There was no recurrence during follow-up.CONCLUSION Thus,CVC-associated thrombosis is a potential source for multiple PDE in PFO patients.

Total colectomy in a colon cancer patient with patent foramen ovale:a case of surgical and anesthetic challenges

A patent foramen ovale(PFO)is a clinical condition linked to ischemic stroke,aura migraine,and other pathologies.Current medical consensus posits that PFO closure may mitigate the risk of recurrent strokes.This case report details the management of a 61-year-old female diagnosed with colon cancer for one month.Preoperative transthoracic echocardiography indicated a potential left-to-right shunt through the foramen ovale and mild regurgitation of both the mitral and aortic valves.The patient’s history revealed previous left-sided migraines,and a review of her medical records disclosed multifocal cerebral infarctions identified by a head CT.A pulmonary artery computed tomography angiography suggested embolization in the anterior branch of the right upper pulmonary artery and several branches of the right lower lung’s posterior and lateral basilar artery,along with thickening of the trunk canals of the pulmonary arteries.After a thorough assessment and extensive consultation with the surgical team,the procedure was transitioned from a laparoscopic radical resection to an open total colectomy.Anesthesia induction required careful avoidance of hypoxia,breath-holding,and coughing.Vigilant management of respiratory and circulatory functions was crucial during periods prone to intraoperative embolism formation.Postoperatively,attention was given to the stabilization of respiratory and circulatory functions during extubation,ensuring adequate sputum suction to prevent choking and close monitoring of breathing to avert airway obstruction post-extubation.Additionally,the patient was closely monitored for postoperative nausea and vomiting,a high-risk condition for this patient cohort.Strategies were implemented to minimize the risk of right-to-left shunting,ensuring the patient’s vital signs remained stable throughout the perioperative period.The patient was discharged safely after a 10-day recovery.For patients with cancer and PFO,comprehensive risk assessment and meticulous safety management are paramount.This case confirms the patient’s history of patent foramen ovale through the association between some atypical symptoms such as migraine,pulmonary embolism and cerebral infarction,which provides guidance for the management of anesthesia in the perioperative period,offering significant clinical implications.

Safety and Efficacy of Biodegradable Patent Foramen Ovale Occluder in Patients with Migraine:A Clinical Trial

Background:Transcatheter closure of patent foramen ovale(PFO)has been widely accepted as a highly effective way to treat high-risk PFO-related diseases.However,traditional non-degradable occluders made of metal alloys will permanently exist in the body,resulting in thrombosis,valve damage,hemolysis,arrhythmia,or other complications.The biodegradable PFO occluder developed by Shanghai Mallow Medical Instrument Co.,Ltd.,China can be fully absorbed and degrade into nontoxic ingredients,reducing postoperative complications.Objectives:To study the safety and efficacy of biodegradable PFO occluders in treating PFO.Methods:This single-center clinical trial collected 30 patients treated with a biodegradable PFO occluder.The follow-up period lasted 12 months to analyze the echocardiographic characteristics and headache relief through HIT-6 scores.Results:The immediate success rate was 100%,with no intraoperative severe occlusion-related complications.The contrast transcranial Doppler(cTCD)at 12 months showed that all patients’right-to-left shunts(RLS)were grade I or 0 with no serious postoperative complications,indicating the overall success rate was 100%.The biodegradable PFO occluder mostly degraded six months after the occlusion.Conclusion:PFO closure with a Mallow biodegradable occluder is safe and effective and has no severe complications.

Platypnea-Orthodeoxia Syndrome in an Elderly Patient Treated with Percutaneous Patent Foramen Ovale Closure: Report of a Case and Review of the Literature

Introduction: Platypnea-Orthodeoxia syndrome is characterized by dyspnea and hypoxia in the upright position, usually improving in the supine position. Two components are required: an interatrial or intrapulmonary shunt, and a functional component. Diagnosis is made by contrast ultrasonography. We report a case of Platypnea-Orthodeoxia syndrome revealed by positional dyspnea in an 87-year-old patient. The aim of this study is to describe the clinical, therapeutic and evolutionary profile of this syndrome. Case Presentation: This is an 87-year-old patient with a history of pulmonary embolism (PE) and stroke. He was seen for dyspnea and desaturation in orthostatism, revealing a patent foramen ovale (PFO). Progression was favorable after closure of the PFO. Conclusion: Platypnea-Orthodeoxia syndrome may be presented as simple exertional dyspnea. The clinician should check for improvement in symptoms and/or oxygenation during decubitus. Definitive treatment consists of percutaneous closure of the shunt.

基于OVAL的新型漏洞评估系统

漏洞评估技术基于防患于未然思想,采用主动探测方法发现系统存在的安全漏洞并提供相应解决方案.针对目前漏洞评估系统存在误报率高、扫描时间长且需要开发攻击代码的缺点,本文提出一种基于OVAL的新型漏洞评估系统.该系统由控制台、数据中心和检测代理3大模块组成,这三个模块协同实现漏洞评估.与现有漏洞评估系统相比,具有精度高、对目标系统性能影响小、评估时间短和可扩展性强的优点,而且免除传统漏洞评估系统所需的攻击代码开发工作.

从OVAL漏洞信息转换到Nessus扫描插件的研究与实现

网络安全漏洞扫描应充分考虑执行的效率和信息的共享。本文通过对OVAL和Nessus的介绍,分析O- VAL Definition与Nessus plugin之间的异同,提出并实现了一种将OVAL公布的漏洞信息转换成Nessus扫描插件的方法,共享了漏洞信息,并提升了漏洞检测的品质。最后经过实验说明该方法的可行性。

汽车试验场高速环道几何线形设计研究及程序开发

在既有高速环道理论基础上对高速环道几何线形设计进行深入研究,在对比了麦克康奈尔(McConnell)和布劳斯(Bloss)缓和曲线设计法的特点后,引入积分算法对麦克康奈尔曲线的计算进行优化,并结合实际应用开发了汽车试验场高速环道几何线形设计程序(OTD)。

OVALS海洋资料同化系统并行计算研究

海洋数值预报技术的发展与高性能计算密切相关。为提高OVALS海洋资料同化系统的时效性,本文实现了OVALS系统的并行化。在温盐资料同化模块并行化过程中,本文提出了层优先处理器划分算法,并研究了基于该算法的并行I/O、全局通讯等实现方法;在高度计资料同化模块并行化过程中,设计实现了基于预处理的非规则区域分解算法,较好地实现了OVALS并行计算负载平衡。数值实验表明,OVALS并行系统在36并行规模下取得了17.45的并行加速比。

The calculation of the Reproducibility Error in the technological system with the clamp on the gas power

The paper deduced a calculation formula by the classic control theory on the Reproducibility Error of parts processing in the technology system,the flexible clamp system, with the clamping device on the gas power,and analyzed its influencing factor with examples,the Reproducibility Error law:\ The larger the diameter of the cylinder,the smaller the error; the slower the tool speed,(k values smaller),the smaller the error.

基于OVAL新型漏洞检测器漏洞库的设计与实现

针对目前主流的漏洞扫描技术中漏洞库的不完整,本文提出了一种新型的基于OVAL的漏洞检测器,其漏洞库可根据需要扫描系统软件、硬件和配置信息等,并以此确定系统中存在的安全漏洞。此检查器所能扫描的操作系统很多,该篇文章以RedHat为载体讲述工作原理和实现。

分布式漏洞检测系统的设计与实现

针对目前主流的漏洞检测工具检测时间长、误报率高以及使用攻击代码影响系统运行等缺点,提出了一种基于OVAL的分布式漏洞检测系统,采用基于主机的漏洞检测方法发现系统存在的安全漏洞.该系统由检测代理和中心管理子系统组成,其中检测代理执行检测插件对目标主机系统进行漏洞检测,而中心管理子系统提供安全知识定义和检测算法.经实验测试,与其他漏洞检测工具相比,具有检测速度快、精度高、对网络运行状况影响小和可扩展性强的优点.适用于检测大规模局域网中各主机系统的漏洞状况.

川芎内生菌Pseudeurotium ovale代谢产物研究

通过大孔树脂柱层析、凝胶柱层析和高效液相色谱等方法对川芎中分离得到的内生菌Pseudeurotium ovale的代谢物进行分离纯化,从中分离得到5个化合物,并通过核磁共振和质谱等波谱学技术手段确认所有化合物的结构,其中包含一个新的化合物4-methoxy-3-methyl-6-(1 E,3 E)-1,3-pentadien-1-yl-2 H-pyran-2-one(1)和四个首次从中分离得到的已知化合物:(2 E,4 E)-1-(2,6-dihydroxy-3,5-dimethylphenyl)-2,4-hexadien-1-one(2)、2-deoxy-sohirnone C(3)、trichodimerol(4)、3,7-dihydroxy-1,9-dimethyl-dibenzofuran(5)。体外抗炎活性测试表明化合物1可抑制经脂多糖(LPS)处理的RAW 264.7细胞中NO、IL-6和TNF-α等炎症因子的分泌。

NUMERICAL SIMULATION OF ROUND TO OVAL ROLLING PROCESS

Three dimensional thermal-mechanical coupled elasto-plastic FEM has been used for simulation of round to oval single pass rolling. The analysis was conducted using MARC/AUTOFORCE1. 2 code. The material is assumed to be elasto-plastic and it obey the Von Mises yield criterion and Prandtl- Reuss rule. Deformation of the workpiece is simulated in a step-by-step manner,updating the coordinates of material points and the property after each step, so that both nonsteady-state and stendy-state deformation can be simulated. The heat transfter between the workpiece, the rolls, and enviroment and the heat generation due to plastic work and friction force, are considered in the analys- is.Predicted the deformation shape of the workpiece, distributions of strains, stresses, strain rates and temperatures, roll-separating force and roll torque are presented.

Hepatic non-parenchymal cells and extracellular matrix participate in oval cell-mediated liver regeneration

AIM： To elucidate the interaction between non- parenchymal cells, extracellular matrix and oval cells during the restituting process of liver injury induced by partial hepatectomy （PH）. METHODS： We examined the localization of oval cells, non-parenchymal cells, and the extracellular matrix components using immunohistochemical and double immunofluorescent analysis during the proliferation and differentiation of oval cells in N-2- acetylaminofluorene （2-AAF）/PH rat model. RESULTS： By day 2 after PH, small oval cells began to proliferate around the portal area. Most of stellate cells and laminin were present along the hepatic sinusoids in the periportal area. Kupffer cells and fibronectin markedly increased in the whole hepatic Iobule. From day 4 to 9, oval cells spread further into hepatic parenchyma, closely associated with stellate cells, fibronectin and laminin. Kupffer cells admixed with oval cells by day 6 and then decreased in the periportal zone. From day 12 to 15, most of hepatic stellate cells （HSCs）, laminin and fibronectin located around the small hepatocyte nodus, and minority of them appeared in the nodus. Kupffer cells were mainly limited in the pericentral sinusoids. After day 18, the normal liver Iobule structures began to recover.CONCLUSION： Local hepatic microenvironment may participate in the oval cell-mediated liver regeneration through the cell-cell and cell-matrix interactions.

Activation of canonical Wnt signaling pathway promotes proliferation and self-renewal of rat hepatic oval cell line WB-F344 in vitro

AIM： To investigate the effect of activation of canonical Wnt signaling pathway on the proliferation and differentiation of hepatic oval cells in vitro. METHODS： WB-F344 cells were treated with recombinant Wnt3a （20, 40, 80, 160, 200 ng/mL） in serum-free medium for 24 h. Cell proliferation was measured by Brdu incorporation analysis; untreated WB-F344 cells were taken as controls. After treatment with Wnt3a （160 ng/mL） for 24 h, subcellular localization and protein expression of p-catenin in WB-F344 cells treated and untreated with Wnt3a were examined by immunofluorescence staining and Western blot analysis. CyclinD1 mRNA expression was determined by semi-quantitative reverse-transcript polymerase chain reaction （RT-PCR）. The mRNA levels of some phenotypic markers （AFP, CK-19, ALB） and two hepatic nuclear factors （HNF-4, HIVF-6） were measured by RT-PCR. Expressions of CK-19 and AFP protein were detected by Western blot analysis. RESULTS： Wnt3a promoted proliferation of WB-F344 cells. Stimulation of WB-F344 cells with recombinant Wnt3a resulte^l in accumulation of the transcriptional activator β-catenin, together with its translocation into the nuclei, and up-regulated typical Wnt target gene CyclinD1. After 3 d of Wnt3a treatment in the absence of serum, WB-F344 cells retained their bipotential to express several specific phenotypic markers of hepatocytes and cholangiocytes, such as AFP and CK-19, following activation of the canonical Wnt signaling pathway. CONCLUSION： The canonical Wnt signaling pathway promotes proliferation and self-renewal of rat hepatic oval cells.

Patent foramen ovale closure reduces recurrent stroke risk in cryptogenic stroke:A systematic review and metaanalysis of randomized controlled trials

AIM To investigate if patent foramen ovale(PFO) closure device reduces the risk of recurrent stroke in patients with cryptogenic stroke.METHODS We searched five databases-Pub Med,EMBASE,Cochrane,CINAHL and Web-of-Science and clinicaltrials.gov from January 2000 to September 2017 for randomized trials comparing PFO closure to medical therapy in cryptogenic stroke.Heterogeneity was determined using Cochrane's Q statistics.Random effects model was used.RESULTS Five randomized controlled trials with 3440 patients were included in the analysis.Mean follow-up was 50 ± 20 mo.PFO closure was associated with a 41% reduction in incidence of recurrent strokes when compared to medical therapy alone in patients with cryptogenic stroke [risk ratio(RR): 0.59,95%CI: 0.40-0.87,P = 0.008].Atrial fibrillation was higher with device closure when compared to medical therapy alone(RR: 4.97,95%CI: 2.22-11.11,P < 0.001).There was no difference between the two groups with respect to all-cause mortality,major bleeding or adverse events.CONCLUSION PFO device closure in appropriately selected patients with moderate to severe right-to-left shunt and/or atrial septal aneurysm shows benefit with respect to recurrent strokes,particularly in younger patients.Further studies are essential to evaluate the impact of higher incidence of atrial fibrillation seen with the PFO closure device on long-term mortality and stroke rates.

Intrahepatic transplantation of hepatic oval cells for fulminant hepatic failure in rats

AIM： To evaluate the effect of intrahepatic transplantation of hepatic oval cells （HOC） on fulminant hepatic failure （FHF） in rats.METHODS： HOC obtained from rats were labeled with green fluocescent protein （GFP） or 5, 6- carboxyfluorescein diacetate succinmidyl ester （CFDASE）. Cell fluorescence was observed under fluorescent microscope at 6, 24, 48 and 72 h after labeling. CFDA- SE labeled HOC （5 × 10^6 cells each rat） were injected into livers of rats with FHF induced by D-galactosamine. Serum albumin （ALB）, alanine aminotransferase （ALT）, aspartate aminotransferase （AST） and total bilirubin （TBil） levels were measured at different time points. Liver function of rats was examined on days 3, 7, 14 and 21 after HOC transplantation.RESULTS： The positive rate of GFP and CFDA-SE labeled HOC was 10% and 90%, respectively, with no significant change in cell viabilities. The survival rate was higher in HOC transplantation group than in control group, especially 48 （9/15 vs 6/15） and 72 h （9/15 vs 4/15） after HOC transplantation. The serum ALT, AST and TBil levels were decreased while the serum AIb level was increased after HOC transplantation. Fluorescence became faded and diffused in liver tissues, suggesting that proliferation and differentiation occur in transplanted HOC.CONCLUSION： CFDA-SE is superior to GFP in labeling HOC, although fluorescence intensity is decreased progressively with cell division. HOC transplantation can improve the liver function and increase the survival rate of recipients.

Clinical relevance of atrial septal aneurysm and patent foramen ovale with migraine

AIM To test the potential association between atrial septal aneurysm(ASA) and migraine in patent foramen ovale(PFO) closure patients through an observational, singlecenter, case-controlled study.METHODS We studied a total of 450 migraineurs who had rightto-left shunts and underwent PFO closure in a retrospective single-center non-randomized registry from February 2012 to October 2016 on the condition that they were aged 18-45 years old. Migraine was diagnosed according to the International Classification of Headache Disorders, 3^(rd) edition and evaluated using the Headache Impact Test-6(HIT-6). All patients underwent preoperative transesophageal echocardiography, contrast transthoracic echocardiography, and computed tomography or magnetic resonance imaging examinations, with subsequent fluoroscopy-guided PFO closure. Based on whether they have ASA or not, the patients were divided into two groups: A(PFO with ASA, n = 80) and B(PFO without ASA, n = 370). Baseline characteristics and procedural and follow-up data were reviewed. RESULTS Compared to group B, group A had an increased frequency of ischemic lesions(11.3% vs 6.2%, P = 0.038) and migraine with aura(32.5% vs 21.1%, P = 0.040). The PFO size was significantly larger in group A(P = 0.007). There was no significant difference in HIT-6 scores between the two groups before and at the oneyear follow-up after the PFO closure [61(9) vs 63(9), P = 0.227; 36(13) vs 36(10), P = 0.706].CONCLUSION Despite its small sample size, our study suggests that the prevalence of ASA in PFO with migraine patients is associated with ischemic stroke, larger PFO size, and migraine with aura.