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Investigation of Cavitation in NaCl Solutions in a Sonochemical Reactor Using the Foil Test Method
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作者 Michael Kuchinskiy Tatyana Lyubimova +2 位作者 Konstantin Rybkin Anastasiia Sadovnikova Vasiliy Galishevskiy 《Fluid Dynamics & Materials Processing》 EI 2024年第5期1093-1102,共10页
Ultrasonic baths and sonochemical reactors are widely used in industrial applications dealing with surface cleaningand chemical synthesis. The processes of erosion, cleaning and structuring of the surface can be typic... Ultrasonic baths and sonochemical reactors are widely used in industrial applications dealing with surface cleaningand chemical synthesis. The processes of erosion, cleaning and structuring of the surface can be typically controlledby changing relevant influential parameters. In particular, in this work, we experimentally investigate theeffect of NaCl concentration (0–5.5 mol/L) on the erosion of an aluminum foil under ultrasonic exposure at afrequency of 28 kHz. Special attention is paid to the determination of cavitation zones and their visualizationusing heat maps. It is found that at low NaCl concentration (0.3 mol/L), the foil destruction rate is higher thanin distilled water. At higher concentrations of salt, cavitation takes place mainly in the upper part of the container. 展开更多
关键词 ultrasound NaCl solution foil test cavitation activity
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A Numerical Investigation of the Effect of Boundary Conditions on Acoustic Pressure Distribution in a Sonochemical Reactor Chamber
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作者 Ivan Sboev Tatyana Lyubimova +1 位作者 Konstantin Rybkin Michael Kuchinskiy 《Fluid Dynamics & Materials Processing》 EI 2024年第6期1425-1439,共15页
The intensification of physicochemical processes in the sonochemical reactor chamber is widely used in problems of synthesis,extraction and separation.One of the most important mechanisms at play in such processes is ... The intensification of physicochemical processes in the sonochemical reactor chamber is widely used in problems of synthesis,extraction and separation.One of the most important mechanisms at play in such processes is the acoustic cavitation due to the non-uniform distribution of acoustic pressure in the chamber.Cavitation has a strong impact on the surface degradation mechanisms.In this work,a numerical calculation of the acoustic pressure distribution inside the reactor chamber was performed using COMSOL Multiphysics.The numerical results have revealed the dependence of the structure of the acoustic pressure field on the boundary conditions for various thicknesses of the piezoelectric transducer.In particular,the amplitude of the acoustic pressure is minimal in the case of absorbing boundaries,and the attenuation becomes more significant as the thickness of the piezoelectric transducer increases.In addition,reflective boundaries play a significant role in the formation and distribution of zones of maximum cavitation activity. 展开更多
关键词 ultrasound numerical simulation acoustic pressure field cavitation erosion foil test
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Multiparametric ultrasound as a new concept of assessment of liver tissue damage
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作者 Angela Peltec Ioan Sporea 《World Journal of Gastroenterology》 SCIE CAS 2024年第12期1663-1669,共7页
Liver disease accounts for approximately 2 million deaths per year worldwide.All chronic liver diseases(CLDs),whether of toxic,genetic,autoimmune,or infectious origin,undergo typical histological changes in the struct... Liver disease accounts for approximately 2 million deaths per year worldwide.All chronic liver diseases(CLDs),whether of toxic,genetic,autoimmune,or infectious origin,undergo typical histological changes in the structure of the tissue.These changes may include the accumulation of extracellular matrix material,fats,triglycerides,or tissue scarring.Noninvasive methods for diagnosing CLD,such as conventional B-mode ultrasound(US),play a significant role in diagnosis.Doppler US,when coupled with B-mode US,can be helpful in evaluating the hemodynamics of hepatic vessels and detecting US findings associated with hepatic decompensation.US elastography can assess liver stiffness,serving as a surrogate marker for liver fibrosis.It is important to note that interpreting these values should not rely solely on a histological classification.Contrast-enhanced US(CEUS)provides valuable information on tissue perfusion and enables excellent differentiation between benign and malignant focal liver lesions.Clinical evaluation,the etiology of liver disease,and the patient current comorbidities all influence the interpretation of liver stiffness measurements.These measurements are most clinically relevant when interpreted as a probability of compensated advanced CLD.B-mode US offers a subjective estimation of fatty infiltration and has limited sensitivity for mild steatosis.The controlled attenuation parameter requires a dedicated device,and cutoff values are not clearly defined.Quan-titative US parameters for liver fat estimation include the attenuation coefficient,backscatter coefficient,and speed of sound.These parameters offer the advantage of providing fat quantification alongside B-mode evaluation and other US parameters.Multiparametric US(MPUS)of the liver introduces a new concept for complete noninvasive diagnosis.It encourages examiners to utilize the latest features of an US machine,including conventional B-mode,liver stiffness evaluation,fat quantification,dispersion imaging,Doppler US,and CEUS for focal liver lesion characterization.This comprehensive approach allows for diagnosis in a single examination,providing clinicians worldwide with a broader perspective and becoming a cornerstone in their diagnostic arsenal.MPUS,in the hands of skilled clinicians,becomes an invaluable predictive tool for diagnosing,staging,and monitoring CLD. 展开更多
关键词 Multiparametric ultrasound ultrasound-based elastography Liver stiffness Noninvasive diagnostic test for chronic liver disease Liver steatosis assessment Portal hypertension evaluation
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2mol/L尿素溶血试验在UT-B基因敲除小鼠核型鉴定中的应用 被引量:1
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作者 赵华山 李志满 +6 位作者 吕斌 郭丽荣 梁爽 陈燕 孟艳 杨宝学 赵雪俭 《中国实验诊断学》 2007年第11期1425-1428,共4页
目的探讨2 mol/L尿素溶血试验在UT-B基因敲除小鼠核型鉴定中的作用。方法(1)按SP级动物饲养标准进行饲养和繁殖;以UT-B基因敲除纯合子(UT-B-/-)成年雄鼠与C57/bl雌鼠合笼,繁殖出UT-B基因敲除杂合型小鼠(UT-B+/-,F1代),F1代UT-B+/-雄、... 目的探讨2 mol/L尿素溶血试验在UT-B基因敲除小鼠核型鉴定中的作用。方法(1)按SP级动物饲养标准进行饲养和繁殖;以UT-B基因敲除纯合子(UT-B-/-)成年雄鼠与C57/bl雌鼠合笼,繁殖出UT-B基因敲除杂合型小鼠(UT-B+/-,F1代),F1代UT-B+/-雄、雌鼠交配获F2代小鼠。(2)取F2代小鼠剪尾提取基因组DNA进行核型鉴定筛选纯合子小鼠(UT-B-/-)和野生型小鼠(UT-B+/+);(3)应用2 mol/L尿素溶血试验和肾脏RT-PCR进行UT-B-/-(JKnull)表型鉴定。结果(1)在SP级饲养和繁殖的条件下,已获得足够的UT-B-/-和UT-B+/+小鼠;(2)2 mol/L尿素溶血试验证明,UT-B+/+小鼠和UT-B+/-小鼠的红细胞加入到2 mol/L尿素中立刻溶血,UT-B-/-小鼠的红细胞10 min内不溶显示溶血抵抗。结论2 mol/L尿素溶血试验可准确地鉴定出UT-B-/-小鼠,与基因组DNA的PCR鉴定方法联合应用,可以使引进的UT-B-/-小鼠稳定繁殖、传代。 展开更多
关键词 ut-B 基因敲除 小鼠 尿素 溶血试验
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Endoscopic ultrasound for the diagnosis of chronic pancreatitis 被引量:6
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作者 Tyler Stevens Mansour A Parsi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第23期2841-2850,共10页
Endoscopic ultrasound(EUS) has become a well accepted test for the diagnosis of chronic pancreatitis.Advantages include its ability to detect subtle and severe changes of the pancreatic duct and parenchyma,and its rel... Endoscopic ultrasound(EUS) has become a well accepted test for the diagnosis of chronic pancreatitis.Advantages include its ability to detect subtle and severe changes of the pancreatic duct and parenchyma,and its relative safety compared with endoscopic retrograde cholangiopancreatography.Limitations include inter-and intraobserver variability,operator dependence,and an incomplete understanding of its true accuracy.The Rosemont classif ication has recently been proposed as a weighted,standardized method that may improve EUS chronic pancreatitis scoring.This paper reviews the published evidence regarding the accuracy of EUS in chronic pancreatitis diagnosis,and enumerates the emerging technologies that have been recently studied which may ultimately improve endosonographic imaging of the pancreas. 展开更多
关键词 Chronic pancreatitis Contrast-enhanced endoscopic ultrasound DIAGNOSIS Digital image analysis ELASTOGRAPHY Endoscopic ultrasound Pancreatic function testing Rosemont classification
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Genetic testing vs microforceps biopsy in pancreatic cysts:Systematic review and meta-analysis 被引量:1
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作者 Sandra Faias Luisa Pereira +2 位作者 Angelo Luis Paula Chaves Marilia Cravo 《World Journal of Gastroenterology》 SCIE CAS 2019年第26期3450-3467,共18页
BACKGROUND Carcinoembryonic antigen(CEA)and cytology in pancreatic cystic fluid are suboptimal for evaluation of pancreatic cystic neoplasms.Genetic testing and microforceps biopsy are promising tools for pre-operativ... BACKGROUND Carcinoembryonic antigen(CEA)and cytology in pancreatic cystic fluid are suboptimal for evaluation of pancreatic cystic neoplasms.Genetic testing and microforceps biopsy are promising tools for pre-operative diagnostic improvement but comparative performance of both methods is unknown.AIM To compare the accuracy of genetic testing and microforceps biopsy in pancreatic cysts referred for surgery.METHODS We performed a literature search in Medline,Scopus,and Web of Science for studies evaluating genetic testing of cystic fluid and microforceps biopsy of pancreatic cysts,with endoscopic ultrasound with fine-needle aspiration(EUSFNA)prior to surgery and surgical pathology as reference standard for diagnosis.We evaluated the diagnostic accuracy for:1-benign cysts;2-mucinous low-risk cysts;3-high-risk cysts,and the diagnostic yield and rate of correctly identified cysts with microforceps biopsy and molecular analysis.We also assessed publication bias,heterogeneity,and study quality.RESULTS Eight studies,including 1206 patients,of which 203(17%)referred for surgery who met the inclusion criteria were analyzed in the systematic review,and seven studies were included in the meta-analysis.Genetic testing and microforceps biopsies were identical for diagnosis of benign cysts.Molecular analysis was superior for diagnosis of both low and high-risk mucinous cysts,with sensitivities of 0.89(95%CI:0.79-0.95)and 0.57(95%CI:0.42-0.71),specificities of 0.88(95%CI:0.75-0.95)and 0.88(95%CI:0.80-0.93)and AUC of 0.9555 and 0.92,respectively.The diagnostic yield was higher in microforceps biopsies than in genetic analysis(0.73 vs 0.54,respectively)but the rates of correctly identified cysts were identical(0.73 with 95%CI:0.62-0.82 vs 0.71 with 95%CI:0.49-0.86,respectively).CONCLUSION Genetic testing and microforceps biopsies are useful second tests,with identical results in benign pancreatic cysts.Genetic analysis performs better for low-and high-risk cysts but has lower diagnostic yield. 展开更多
关键词 Pancreatic CYSTS ENDOSCOPIC ultrasound ENDOSCOPIC ultrasound with fineneedle ASPIRATION Genetic testing Microforceps BIOPSY Molecular analysis KRAS Carcinoembryonic antigen CYTOLOGY
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Endoscopic ultrasound guided fine needle aspiration and useful ancillary methods 被引量:6
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作者 Mario Tadic Tajana Stoos-Veic Rajko Kusec 《World Journal of Gastroenterology》 SCIE CAS 2014年第39期14292-14300,共9页
The role of endoscopic ultrasound(EUS) in evaluating pancreatic pathology has been well documented from the beginning of its clinical use. High spatial resolution and the close proximity to the evaluated organs within... The role of endoscopic ultrasound(EUS) in evaluating pancreatic pathology has been well documented from the beginning of its clinical use. High spatial resolution and the close proximity to the evaluated organs within the mediastinum and abdominal cavity allow detection of small focal lesions and precise tissue acquisition from suspected lesions within the reach of this method. Fine needle aspiration(FNA) is considered of additional value to EUS and is performed to obtain tissue diagnosis. Tissue acquisition from suspected lesions for cytological or histological analysis allows, not only the differentiation between malignant and non-malignant lesions, but, in most cases, also the accurate distinction between the various types of malignant lesions. It is well documented that the best results are achieved only if an adequate sample is obtained for further analysis, if the material is processed in an appropriate way, and if adequate ancillary methods are performed. This is a multi-step process and could be quite a challenge in some cases. In this article, we discuss the technical aspects of tissue acquisition by EUS-guided-FNA(EUS-FNA), as well as the role of an on-site cytopathologist, various means of specimen processing, and the selection of the appropriate ancillary method for providing an accurate tissue diagnosis and maximizing the yield of this method. The main goal of this review is to alert endosonographers, not only to the different possibilities of tissue acquisition, namely EUS-FNA, but also to bring to their attention the importance of proper sample processing in the evaluation of various lesions in the gastrointestinal tract and other accessible organs. All aspects of tissue acquisition(needles, suction, use of stylet, complications, etc.) have been well discussed lately. Adequate tissue samples enable comprehensive diagnoses, which answer the main clinical questions, thus enabling targeted therapy. 展开更多
关键词 Endoscopic ultrasound Endoscopic ultrasound-guided fine needle aspiration Endoscopic ultrasound-guided tissue acquisition Fine needle aspiration cytology Ancillary studies Molecular testing Flow cytometry immunophenotyping
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UT演示型多媒体课件的制作
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作者 陈江辉 李晓红 《三峡大学学报(自然科学版)》 CAS 2001年第6期553-555,共3页
阐述了以创作软件Flash 5 0及Director 8 0与著作软件Authorware 5 1为开发工具 ,研制超声波演示型多媒体课件的方法和策略 ;同时给出实例介绍了动画制作的技巧 它涵盖了《超声波探伤》基本内容 ,并且动画逼真、生动、形象地反映了... 阐述了以创作软件Flash 5 0及Director 8 0与著作软件Authorware 5 1为开发工具 ,研制超声波演示型多媒体课件的方法和策略 ;同时给出实例介绍了动画制作的技巧 它涵盖了《超声波探伤》基本内容 ,并且动画逼真、生动、形象地反映了波形转换和波阵面传播过程等 完善的交互设计、界面设计和导航系统 。 展开更多
关键词 超声波探伤 多媒体课件 计算机辅助教学 超声波演示型
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AP1000 CB20薄板UT检测方法
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作者 孙豪明 李海涛 +3 位作者 付深庆 张学武 乔春城 王本正 《施工技术》 CAS 北大核心 2016年第S2期478-480,共3页
AP1000 CB20底部锥板与环板之间的T形钢为6.5mm厚钢板,焊接接头形式为CJP,按照设计要求需要进行UT检测。对于板厚在8mm以下的焊缝,目前国内外并没有具体的、系统的检测标准参照。采用焊接模拟件和解剖试验等方法,参照标准要求,研究出一... AP1000 CB20底部锥板与环板之间的T形钢为6.5mm厚钢板,焊接接头形式为CJP,按照设计要求需要进行UT检测。对于板厚在8mm以下的焊缝,目前国内外并没有具体的、系统的检测标准参照。采用焊接模拟件和解剖试验等方法,参照标准要求,研究出一种薄板的UT检测方法,有效地检测了焊缝质量。 展开更多
关键词 核电站 模块 薄板 T形钢 ut检测
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Design and Experiments of Ultrasound Image-Guided Multi-DOF Robot System for Brachytherapy 被引量:3
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作者 Shan Jiang Yunpeng Yang +2 位作者 Zhiyong Yang Zhen Zhang Sheng Liu 《Transactions of Tianjin University》 EI CAS 2017年第5期479-487,共9页
To implant radioactive seeds through a needle precisely and safely, a novel multi-DOF surgical robotic system is presented in this paper for percutaneous prostate intervention through the patient’s perineum under rea... To implant radioactive seeds through a needle precisely and safely, a novel multi-DOF surgical robotic system is presented in this paper for percutaneous prostate intervention through the patient’s perineum under real-time ultrasound image guidance. The proposed robot, which is designed with 9-DOF, consists of a 3-DOF automatic location platform for position adjustment, 2-DOF for automatic ultrasonic probe adjustment mounted with electromagnetic trackers, and 4-DOF for manually adjusting the guided template. Meanwhile, a new registration method based on the quaternion algorithm and least square method is developed, and the needle insertion is performed under the real-time guidance of a navigation system. Furthermore, the robot system has undergone some preliminary experiments with a laser tracker to evaluate the repeatability and accuracy of the robot system. The location error of the puncture needle tip can be controlled under 0.7 mm in air for the whole robotic system. The acquired results endorse the precision of the robot system for prostate seed implantation brachytherapy. © 2017, Tianjin University and Springer-Verlag GmbH Germany. 展开更多
关键词 Implants (surgical) Least squares approximations Machine design Nanocomposites Navigation systems NEEDLES ONCOLOGY Patient treatment Radiotherapy Robotics Ultrasonics UROLOGY
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Model selection for SVM using mutative scale chaos optimization algorithm
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作者 刘清坤 阙沛文 +1 位作者 费春国 宋寿朋 《Journal of Shanghai University(English Edition)》 CAS 2006年第6期531-534,共4页
This paper proposes a new search strategy using mutative scale chaos optimization algorithm (MSCO) for model selection of support vector machine (SVM). It searches the parameter space of SVM with a very high effic... This paper proposes a new search strategy using mutative scale chaos optimization algorithm (MSCO) for model selection of support vector machine (SVM). It searches the parameter space of SVM with a very high efficiency and finds the optimum parameter setting for a practical classification problem with very low time cost. To demonstrate the performance of the proposed method it is applied to model selection of SVM in ultrasonic flaw classification and compared with grid search for model selection. Experimental results show that MSCO is a very powerful tool for model selection of SVM, and outperforms grid search in search speed and precision in ultrasonic flaw classification. 展开更多
关键词 model selection support vector machine (SVM) mutative scale chaos optimization (MSCO) ultrasonic testing ut non-destructive testing (NDT).
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Assessment of Visceral Leishmaniasis Consequences Using Ultrasound
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作者 Mustafa Z. Mahmoud 《Open Journal of Radiology》 2014年第2期201-206,共6页
Background and Aim: Visceral leishmaniasis (VL), also known as kala azar, is a parasitic disease that caused by infection with Leishmania parasites, which are spread by the bite of phlebotomine sand flies. An ultrasou... Background and Aim: Visceral leishmaniasis (VL), also known as kala azar, is a parasitic disease that caused by infection with Leishmania parasites, which are spread by the bite of phlebotomine sand flies. An ultrasound examination is strongly advocated for the promote diagnosis and treatment of VL for long term follow up and evaluation of unresponsive cases. The aim of this study was to assess the consequences of VL in the liver, spleen and pancreas of affected participants by using ultrasound. Materials and Methods: A prospective cohort study was conducted in the period of January 2012 to March 2014 in the ultrasound department of Tropical Disease Hospital (TDH) in Khartoum-Sudan, among a group of 100 participants (84% males, 16% females and their ages ranges from 15 to 45 years) positive to VL and had been diagnosed by laboratory tests;either serological or Napier’s Aldehyde test. The Aloka portable ultrasound machine equipped with 3.5 MHz convex probe was used for abdominal ultrasound scanning. Standard Statistical Package for the Social Sciences (SPSS) was used to analyze the results. Results: The commonest ultrasound findings in VL participants were hepatomegaly (100%), splenomegaly (100%) and ascites (50%). Other complications such as lymphadenopathy (35%), focal splenic lesions (34%), dilated portal vein (7%) and shrinkage liver (4%) were detected. Conclusion: Ultrasound scanning presents an effective role in VL, because of its ability to detect the consequences of this disease in various abdominal organs such as liver, spleen and pancreas earlier, which in turn allowing the possibility to treat these complications and prevents the deterioration of a patient’s health status. 展开更多
关键词 Napier’s ALDEHYDE Test ultrasound SEROLOGICAL TESTS VISCERAL LEISHMANIASIS
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高温声学检测技术的发展、应用与挑战 被引量:2
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作者 卢超 郭伟 +9 位作者 石文泽 陈振华 胡博 陈巍巍 李秋锋 陈尧 刘远 郭双林 朱颖 张萍 《振动.测试与诊断》 EI CSCD 北大核心 2024年第1期1-10,193,共11页
以我国航空航天、钢铁冶金、特种设备等领域的高温声学无损检测技术研究与应用为主线,分析了高温声学检测技术在促进先进高温材料制备与研发、钢铁冶金行业绿色低碳生产和产业升级、高温压力管道安全运行与维护等方面的巨大需求。介绍... 以我国航空航天、钢铁冶金、特种设备等领域的高温声学无损检测技术研究与应用为主线,分析了高温声学检测技术在促进先进高温材料制备与研发、钢铁冶金行业绿色低碳生产和产业升级、高温压力管道安全运行与维护等方面的巨大需求。介绍了国内外在高温声学检测的技术方法和仪器研制等方面取得的进展,分析了压电超声、电磁超声、激光超声、激光电磁超声等技术在高温无损检测应用方面存在的优缺点和应用场景,总结了高温声学检测技术面临的机遇与挑战。 展开更多
关键词 声学检测 高温无损检测 压电超声 电磁超声 激光超声
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Endoscopic ultrasound-guided fine-needle aspiration pancreatic adenocarcinoma samples yield adequate DNA for next-generation sequencing:A cohort analysis
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作者 Stefania Bunduc Bianca Varzaru +10 位作者 Razvan Andrei Iacob Andrei Sorop Ioana Manea Andreea Spiridon Raluca Chelaru Adina Emilia Croitoru Gabriel Becheanu Mona Dumbrava Simona Dima Irinel Popescu Cristian Gheorghe 《World Journal of Gastroenterology》 SCIE CAS 2023年第18期2864-2874,共11页
BACKGROUND Genetic tests are increasingly performed for the management of unresectable pancreatic cancer.For genotyping aimed samples current guidelines recommend using core specimens,although based on moderate qualit... BACKGROUND Genetic tests are increasingly performed for the management of unresectable pancreatic cancer.For genotyping aimed samples current guidelines recommend using core specimens,although based on moderate quality evidence.However,in clinical practice among the endoscopic ultrasound(EUS) guided tissue acquisition methods,fine needle aspiration(FNA) is the most widely performed.AIM To assess the adequacy for next generation sequencing(NGS) of the DNA yielded from EUS-FNA pancreatic adenocarcinoma(PDAC) samples.METHODS Between November 2018 and December 2021,105 patients with PDAC confirmed by EUS-FNA were included in the study at our tertiary gastroenterology center.Either 22 gauge(G) or 19G FNA needles were used.One pass was dedicated to DNA extraction.DNA concentration and purity(A260/280,A260/230) were assessed by spectrophotometry.We assessed the differences in DNA parameters according to needle size and tumor characteristics(size,location) and the adequacy of the extracted DNA for NGS(defined as A260/280 ≥ 1.7,and DNA yield:≥ 10 ng for amplicon based NGS,≥ 50 ng for whole exome sequencing [WES],≥ 100 ng for whole genome sequencing [WGS]) by analysis of variance and ttest respectively.Moreover,we compared DNA purity parameters across the different DNA yield categories.RESULTS Our cohort included 49% male patients,aged 67.02 ± 8.38 years.The 22G needle was used in 71%of the cases.The DNA parameters across our samples varied as follows:DNA yield:1289 ng(inter quartile range:534.75-3101),A260/280 = 1.85(1.79-1.86),A260/230 = 2.2(1.72-2.36).DNA yield was > 10 ng in all samples and > 100 ng in 93% of them(one sample < 50 ng).There were no significant differences in the concentration and A260/280 between samples by needle size.Needle size was the only independent predictor of A260/230 which was higher in the 22G samples(P =0.038).NGS adequacy rate was 90% for 19G samples regardless of NGS type,and for 22G samples it reached 89% for WGS adequacy and 91% for WES and amplicon based NGS.Samples with DNA yield > 100 ng had significantly higher A260/280(1.89 ± 0.32 vs 1.34 ± 0.42,P = 0.013).Tumor characteristics were not corelated with the DNA parameters.CONCLUSION EUS-FNA PDAC samples yield DNA adequate for subsequent NGS.DNA amount was similar between 22G and 19G FNA needles.DNA purity parameters may vary indirectly with needle size. 展开更多
关键词 Pancreatic adenocarcinoma Endoscopic ultrasound guided fine needle aspiration Next generation sequencing DNA yield Needle size Genetic testing
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Development of Safety Factors for the UT Data Analysis Method in Plant Piping
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作者 Hun Yun Kyeong-Mo Hwang Chan-Kyoo Lee 《World Journal of Nuclear Science and Technology》 2013年第4期143-149,共7页
There are several thousand piping components in a nuclear power plant. These components are affected by degradation mechanisms such as FAC (Flow-Accelerated Corrosion), cavitation, flashing, and LDI (Liquid Droplet Im... There are several thousand piping components in a nuclear power plant. These components are affected by degradation mechanisms such as FAC (Flow-Accelerated Corrosion), cavitation, flashing, and LDI (Liquid Droplet Impingement). Therefore, nuclear power plants implement inspection programs to detect and control damages caused by such mechanisms. UT (Ultrasonic Test), one of the non-destructive tests, is the most commonly used method for inspecting the integrity of piping components. According to the management plan, several hundred components, being composed of as many as 100 to 300 inspection data points, are inspected during every RFO (Re-Fueling Outage). To acquire UT data of components, a large amount of expense is incurred. It is, however, difficult to find a proper method capable of verifying the reliability of UT data prior to the wear rate evaluation. This study describes the review of UT evaluation process and the influence of UT measurement error. It is explored that SAM (Square Average Method), which was suggested as a method for reliability analysis in the previous study, is found to be suitable for the determination whether the measured thickness is acceptable or not. And, safety factors are proposed herein through the statistical analysis taking into account the components’ type. 展开更多
关键词 WALL THINNING ut (Ultrasonic Test) Reliability Analysis FAC (Flow-Accelerated Corrosion) Safety Factor Measurement Data
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Simulation study on ultrasonic tomography for grouted reinforced concrete by finite element
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作者 朱自强 喻波 +2 位作者 李亚楠 肖嘉莹 周勇 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第7期2791-2799,共9页
A finite element reconstruction algorithm for ultrasound tomography based on the Helmholtz equation in frequency domain is presented to monitor the grouting defects in reinforced concrete structures.In this algorithm,... A finite element reconstruction algorithm for ultrasound tomography based on the Helmholtz equation in frequency domain is presented to monitor the grouting defects in reinforced concrete structures.In this algorithm,a hybrid regularizations-based iterative Newton method is implemented to provide stable inverse solutions.Furthermore,a dual mesh scheme and an adjoint method are adopted to reduce the computation cost and improve the efficiency of reconstruction.Simultaneous reconstruction of both acoustic velocity and attenuation coefficient for a reinforced concrete model is achieved with multiple frequency data.The algorithm is evaluated with numerical simulation under various practical scenarios including varied transmission/receiving modes,different noise levels,different source/detector numbers,and different contrast levels between the heterogeneity and background region.Results obtained suggest that the algorithm is insensitive to noise,and the reconstructions are quantitatively accurate in terms of the location,size and acoustic properties of the target over a range of contrast levels. 展开更多
关键词 ultrasound computed tomography nondestructive testing concrete exact field finite element method
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Analysis of the characteristics of diabetic peripheral nerve damage by high frequency ultrasound combined with QTT
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作者 Pei Hu Bin Xiao +5 位作者 Rui Xue De-Jiao Sun Zheng-Sen Dong Tian-Xin Hu Jia-Jing Wang Guang-Mei Zheng 《Journal of Hainan Medical University》 2019年第7期15-20,共6页
Objective: High frequency ultrasound combined with policy thermal perception testing (QTT) was used to analyze the characteristics of nerve damage in diabetic peripheral neuropathy (DPN), and then provided the basis f... Objective: High frequency ultrasound combined with policy thermal perception testing (QTT) was used to analyze the characteristics of nerve damage in diabetic peripheral neuropathy (DPN), and then provided the basis for the clinical prevention, diagnosis and treatment of DPN. Methods: A total of 110 DPN patients admitted to the hospital from December 2015 to May 2018 were selected, and the characteristics of nerve damage in diabetic peripheral neuropathy were analyzed by ultrasound and QTT. Results: In the results of QTT, the abnormal proportion of the CDT, WDT, CPT and HPT of the lower limbs in DPN's were all higher than the upper limbs;The difference of WDT and HPT in the age and course groups of patients in the upper limbs was statistically significant, the abnormal proportion of WDT and HPT in patients aged 60 years or above or with a course of 10 years or more were all above 45%, higher than those in other groups. The patients with larger mean amplitude of glycemic excursions (MAGE) were significantly higher than those with smaller MAGE, regardless of the abnormal proportion of WDT and HPT observed in upper limbs, lower limbs or upper and lower limbs;The results of ultrasonic measurement of nerve cross sectional area showed: the proportion of patients with ulnar nerve and median nerve abnormally thickened in the high age group (≥45 years) and the long course group (>10 years) was significantly higher than that in the low age group (<45 years) and the short course group (<10 years), the proportion of patients with larger MAGE with abnormal enlargement of median nerve was significantly higher than those with smaller MAGE. The thickening of ulnar nerve, median nerve and peroneal nerve was obvious in the patients of MAGE > 4 mmol/L. Conclusion: (1) The main nerve damage in DPN patients was thermal sensation damage, and the lower limb nerve was more vulnerable than the upper limb nerve. (2) The incidence of ulnar and median nerve damage was higher in patients aged 45 years and older or over 10 years of course. (3) Patients with large MAGE (> 4 mmo/L) had higher incidence of median nerve damage. The above characteristics of nerve damage can provide basis for clinical prevention, diagnosis and treatment of DPN. 展开更多
关键词 Quantitative thermal PERCEPTION testing ultrasound DIABETIC PERIPHERAL NEUROPATHY Cross sectional area Mean AMPLITUDE of glycemic EXCURSIONS
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An Automated Ultrasonic NDT System for In-Situ Inspection of Wind Turbine Blades
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作者 Tat-Hean Gan Guoliang Ye +3 位作者 Ben Neal Alex Boot Vassilios Kappatos Cem Selcuk 《Journal of Mechanics Engineering and Automation》 2014年第10期781-788,共8页
It is crucial to maintain wind turbine blades regularly, due to the high stress leading to defects or damage. Conventional methods require shipping the blades to a workshop for off-site inspection, which is extremely ... It is crucial to maintain wind turbine blades regularly, due to the high stress leading to defects or damage. Conventional methods require shipping the blades to a workshop for off-site inspection, which is extremely time-consuming and very costly. This work investigates the use of pulse-echo ultrasound to detect internal damages in wind turbine blades without the necessity to ship the blades off-site. A prototype 2D ultrasonic NDT (non-destructive testing) system has been developed and optimised for in-situ wind turbine blade inspection. The system is designed to be light weight so it can be easily carried by an inspector onto the wind turbine blade for in-situ inspection. It can be operated in 1D A-scan, 2D C-scan or 3D volume scan. A software system has been developed to control the automated scanning and show the damage areas in a 2D/3D map with different colours so that the inspector can easily identify the defective areas. Experiments on GFRP (glass fibre reinforced plastics) and wind turbine blades (made of GFRP) samples showed that internal defects can be detected. The main advantages of this system are fully automated 2D spatial scanning and the ability to alert the user to the damage of the inspected sample. It is intended to be used for in-situ inspection to save maintenance time and hence considered to be economically beneficial for the wind energy industry. 展开更多
关键词 ultrasound non-destructive testing wind turbine blade glass fibre reinforced plastics defect detection.
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正交试验法优化紫苏叶中总黄酮提取工艺及体外抗氧化活性研究 被引量:2
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作者 尹丽 孟学林 《饲料研究》 CAS 北大核心 2024年第4期99-103,共5页
试验以紫苏叶为研究对象,在单因素试验基础上,通过正交试验优化紫苏叶总黄酮的提取工艺,探讨总黄酮的抗氧化活性。以紫苏叶总黄酮得率为考察指标,对乙醇浓度、液料比、提取温度和提取时间进行优化。结果表明,4个因素对紫苏叶总黄酮得率... 试验以紫苏叶为研究对象,在单因素试验基础上,通过正交试验优化紫苏叶总黄酮的提取工艺,探讨总黄酮的抗氧化活性。以紫苏叶总黄酮得率为考察指标,对乙醇浓度、液料比、提取温度和提取时间进行优化。结果表明,4个因素对紫苏叶总黄酮得率影响的主次顺序为:提取温度>乙醇浓度>液料比>提取时间。紫苏叶总黄酮最优提取工艺参数为乙醇浓度50%、液料比20 mL/g、提取温度70℃和提取时间45 min。在此条件下,紫苏叶总黄酮得率为4.05%。紫苏叶总黄酮对DPPH自由基与羟自由基具有较强的清除作用,其IC50值分别为160 mg/L和196 mg/L。研究表明,紫苏叶总黄酮具有较强的抗氧化性能,是一种优质的天然抗氧化物质。 展开更多
关键词 紫苏叶 总黄酮 正交试验 抗氧化活性 超声辅助提取
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DNA无创产前检测及彩色多普勒超声检查在高危孕妇胎儿 染色体异常筛查中的应用价值 被引量:1
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作者 成艳 马雯 +2 位作者 权秋宁 于青 杜小云 《检验医学与临床》 CAS 2024年第2期217-220,共4页
目的探讨DNA无创产前检测(NIPT)及彩色多普勒超声(简称彩超)检查在高危孕妇胎儿染色体异常筛查中的应用价值。方法选取2020年1月至2022年12月于该院接受产前检查的5862例高危孕妇作为研究对象,均接受NIPT、彩超检查,以羊水穿刺结果或分... 目的探讨DNA无创产前检测(NIPT)及彩色多普勒超声(简称彩超)检查在高危孕妇胎儿染色体异常筛查中的应用价值。方法选取2020年1月至2022年12月于该院接受产前检查的5862例高危孕妇作为研究对象,均接受NIPT、彩超检查,以羊水穿刺结果或分娩结局作为诊断胎儿染色体异常的金标准,比较NIPT、彩超检查及二者联合检查对高危孕妇胎儿染色体异常的诊断效能。结果5862例高危孕妇中共检出167例胎儿染色体异常,检出率为2.85%。167例胎儿染色体异常中胎儿染色体数目异常161例,构成比为96.41%;胎儿染色体结构异常6例,构成比为3.59%。彩超检查共诊断出119例孕妇胎儿染色体异常,经一致性分析,彩超检查诊断胎儿染色体异常的灵敏度为0.713,特异度为0.884,准确率为87.96%,Kappa=0.215,P<0.05。NIPT共诊断出133例孕妇胎儿染色体异常,经一致性分析,NIPT诊断胎儿染色体异常的灵敏度为0.796,特异度为0.945,准确率为94.05%,Kappa=0.408,P<0.05。彩超检查联合NIPT共诊断出158例孕妇胎儿染色体异常,经一致性分析,二者联合检查诊断胎儿染色体异常的灵敏度为0.946,特异度为0.986,准确率为98.50%,Kappa=0.775,P<0.05。结论NIPT与彩超检查用于筛查高危孕妇胎儿染色体异常均具有一定价值,二者联合检查可获得更高的灵敏度、特异度和准确率,能有效降低漏诊及误诊风险。 展开更多
关键词 DNA无创产前检测 彩色多普勒超声检查 高危孕妇 胎儿染色体异常 应用价值
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