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Sample records for two-and three-dimensional echocardiography

  1. Three-dimensional echocardiography

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    Buck, Thomas [University Hospital Essen (Germany). West German Heart Center; Franke, Andreas [Klinikum Region Hannover - Klinikum Siloah, Hannover (Germany). Dept. of Cardiology, Angiology and Intensive Care Medicine; Monaghan, Mark J. (eds.) [King' s College Hospital, London (United Kingdom)

    2011-07-01

    Presents tips and tricks for beginners and experts Provides educational material for 3D training courses Features comprehensively illustrated cases Includes an accompanying DVD with video clips of all sample cases Three-dimensional echocardiography is the most recent fundamental advancement in echocardiography. Since real-time 3D echocardiography became commercially available in 2002, it has rapidly been accepted in echo labs worldwide. This book covers all clinically relevant aspects of this fascinating new technology, including a comprehensive explanation of its basic principles, practical aspects of clinical application, and detailed descriptions of specific uses in the broad spectrum of clinically important heart disease. The book was written by a group of well-recognized international experts in the field, who have not only been involved in the scientific and clinical evolution of 3D echocardiography since its inception but are also intensively involved in expert training courses. As a result, the clear focus of this book is on the practical application of 3D echocardiography in daily clinical routine with tips and tricks for both beginners and experts, accompanied by more than 150 case examples comprehensively illustrated in more than 800 images and more than 500 videos provided on a DVD. In addition to an in-depth review of the most recent literature on real-time 3D echocardiography, this book represents an invaluable reference work for beginners and expert users of 3D echocardiography. - Tips and tricks for beginners and experts - Educational material for 3D training courses - Comprehensively illustrated cases - DVD with video clips of all sample cases.

  2. Advanced Three-Dimensional Echocardiography

    NARCIS (Netherlands)

    B. Ren (Ben)

    2014-01-01

    markdownabstract__Abstract__ During the development of echocardiography, 3D echocardiography imaging represents a major innovation in cardiovascular ultrasound (Figure 1). Advancements in computer and transducer technologies permit real-time 3D acquisition and presentation of cardiac

  3. Three-dimensional echocardiography in valve disease.

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    Colombo, Chiara; Tamborini, Gloria; Pepi, Mauro; Alimento, Marina; Fiorentini, Cesare

    2007-01-01

    This review covers the role of three-dimensional (3D) echocardiography in the diagnosis of heart valve disease. Several factors have contributed to the evolution of this technique, which is currently a simple and routine method: rapid evolution in probe and computer technologies, demonstration that 3D data sets allowed more complete and accurate evaluation of cardiac structures, emerging clinical experience indicating the strong potential particularly in valve diseases, volume and function of the two ventricle measurements and several other fields. This report will review current and future applications of 3D echocardiography in mitral, aortic and tricuspid valve diseases underlying both qualitative (morphologic) and quantitative advantages of this technique.

  4. Artifacts in three-dimensional transesophageal echocardiography.

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    Faletra, Francesco Fulvio; Ramamurthi, Alamelu; Dequarti, Maria Cristina; Leo, Laura Anna; Moccetti, Tiziano; Pandian, Natesa

    2014-05-01

    Three-dimensional (3D) transesophageal echocardiography (TEE) is subject to the same types of artifacts encountered on two-dimensional TEE. However, when displayed in a 3D format, some of the artifacts appear more "realistic," whereas others are unique to image acquisition and postprocessing. Three-dimensional TEE is increasingly used in the setting of percutaneous catheter-based interventions and ablation procedures, and 3D artifacts caused by the metallic components of catheters and devices are particularly frequent. Knowledge of these artifacts is of paramount relevance to avoid misinterpretation of 3D images. Although artifacts and pitfalls on two-dimensional echocardiography are well described and classified, a systematic description of artifacts in 3D transesophageal echocardiographic images and how they affect 3D imaging is still absent. The aim of this review is to describe the most relevant artifacts on 3D TEE, with particular emphasis on those occurring during percutaneous interventions for structural heart disease and ablation procedures.

  5. Fine-tuning management of the Heart Assist 5 left ventricular assist device with two- and three-dimensional echocardiography

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    Demirozu, Zumrut Tuba; Kucukaksu, Deniz Suha; Arat, Nurcan

    2016-01-01

    Summary Introduction: Left ventricular assist device (LVAD) implantation is a viable therapy for patients with severe end-stage heart failure, providing effective haemodynamic support and improved quality of life. The Heart Assist 5 (Micromed Cardiovascular Inc, Houston, TX) continuous-flow LVAD has been on the market in Europe since May 2009. Methods: We evaluated nine Heart Assist 5 LVAD patients with two- and three-dimensional transthoracic echocardiographic (TTE) and transoesophageal echocardiographic (TEE) parameters between December 2011 and December 2013. The pre-operative TTE LVAD evaluations included left ventricular (LV) function and structure, quantification of right ventricular (RV) function and tricuspid regurgitation (TR), assessment of aortic and mitral regurgitation, and presence of patent foramen ovale and intra-cardiac clots. Peri-operative TEE determined the inflow cannula and septum position, and assessed the de-airing process while weaning from cardiopulmonary bypass. Post-operative serial follow-up TTE showed the surgical results of LVAD implantation, determined the overall structure and function of the LV, RV and TR, and observed the inflow and outflow cannula position. Results: Nine patients who had undergone Heart Assist 5 LVAD implantation and had been followed up for more than 30 days were included in this study. Eight patients had ischaemic cardiomyopathy and one had adriamycin-induced cardiomyopathy. Pre-implantation data: the mean age of the patients was 52 ± 13 (34–64) years, mean body surface area (BSA) was 1.8 ± 0.2 (1.6–2.0) m2, mean cardiac index (CI) was 2.04 ± 0.4 (1.5–2.6) l/min/m2, mean cardiac output (CO) was 3.7 ± 0.7 (2.6–4.2) l/min, mean ejection fraction (EF) was 23 ± 5 (18–28)%, and right ventricular fractional area contraction (RVFAC) was 43 ± 9 (35–55)%. One patient had aortic valve replacement (AVR) during the LVAD implantation, and excess current alarms and increased power were suspected to be

  6. Three-dimensional Echocardiography in Valvular Heart Disease.

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    Kurklinsky, Andrew; Mankad, Sunil

    2012-01-01

    Recent technologic advances in 3-dimensional (3D) echocardiography, using parallel processing to scan a pyramidal volume, have allowed for a superior ability to describe valvular anatomy using both transthoracic and transesophageal echocardiography. Although still in evolution and at an early phase of adaptation with respect to its clinical application, 3D echocardiography has emerged as an important clinical tool in the assessment of valvular heart disease. Three-dimensional echocardiography provides unique perspectives of valvular structures by presenting "en face" views of valvular structures, allowing for a better understanding of the topographical aspects of pathology, and a refined definition of the spatial relationships of intracardiac structures. Three-dimensional echocardiography makes available indices not described by 2D echocardiography and has been demonstrated to be superior to 2D echocardiography in a variety of valvular disease scenarios. The information gained from 3D echocardiography has especially made an impact in guiding clinical decisions in the evaluation of mitral valve (MV) disease. The decision of early surgery in degenerative MV disease is based on the suitability of repair, and the suitability of repair is generally based on echocardiography. The superior understanding of MV anatomy afforded by 3D echocardiography has been shown to be quite valuable in this setting. This review will describe the contemporary use of 3D echocardiography in the assessment of valvular heart disease, including MV, aortic, tricuspid, and prosthetic valve abnormalities. This article illustrates how 3D echocardiography can complement current echocardiography techniques in the management of valvular heart disease.

  7. Automated analysis of three-dimensional stress echocardiography

    NARCIS (Netherlands)

    K.Y.E. Leung (Esther); M. van Stralen (Marijn); M.G. Danilouchkine (Mikhail); G. van Burken (Gerard); M.L. Geleijnse (Marcel); J.H.C. Reiber (Johan); N. de Jong (Nico); A.F.W. van der Steen (Ton); J.G. Bosch (Johan)

    2011-01-01

    textabstractReal-time three-dimensional (3D) ultrasound imaging has been proposed as an alternative for two-dimensional stress echocardiography for assessing myocardial dysfunction and underlying coronary artery disease. Analysis of 3D stress echocardiography is no simple task and requires considera

  8. Usefulness of three-dimensional echocardiography in the assessment of valvular involvement in Loeffler endocarditis.

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    Hernandez, Carlos M; Arisha, Mohammed J; Ahmad, Amier; Oates, Ethan; Nanda, Navin C; Nanda, Anil; Wasan, Anita; Caleti, Beda E; Bernal, Cinthia L P; Gallardo, Sergio M

    2017-07-01

    Loeffler endocarditis is a complication of hypereosinophilic syndrome resulting from eosinophilic infiltration of heart tissue. We report a case of Loeffler endocarditis in which three-dimensional transthoracic and transesophageal echocardiography provided additional information to what was found by two-dimensional transthoracic echocardiography alone. Our case illustrates the usefulness of combined two- and three-dimensional echocardiography in the assessment of Loeffler endocarditis. In addition, a summary of the features of hypereosinophilic syndrome and Loeffler endocarditis is provided in tabular form. © 2017, Wiley Periodicals, Inc.

  9. Live three-dimensional transesophageal echocardiography in mitral valve surgery

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    MA Ning; LI Zhi-an; MENG Xu; YANG Ya

    2008-01-01

    Background Live three-dimensional transesophageal echocardiography (live-3D-TEE) is a new technique, but its clinical value is unclear at present. This study aimed to investigate the feasibility, imaging quality and accuracy of live-3D-TEE for assessing mitral valve morphology to determine if live-3D-TEE has important value in mitral valve surgery.Methods Twenty-four patients with mitral valve disease (mean age (47.1 rdiography (2D-TEE) before and after mitral valve surgery. Sensitivity, specificity, and total consistency rates of live-3D-TEE for diagnosing ruptured chordae were calculated and compared to surgeon's findings. We also compared the diagnostic accuracy of mitral valve disease between live-3D-TEE and 2D-TEE.Results Live-3D-TEE allowed visualization of the anatomic structure of the heart online and clearly identified the valvular apparatus and their defects. Sensitivity and specificity for the detection of ruptured chordae by live-3D-TEE were 87.5% and 100% respectively, and the total consistency rate was 95.8%. Additional defects not diagnosted by 2D-TEE were found in three cases (12.5%) preoperatively by live-3D-TEE. Live-3D-TEE could evaluate the function of prosthetic or native valves immediately after operation. One case was re-repaired (4.2%) using guidance by live-3D-TEE. Conclusion Live-3D-TEE enabled evaluation of mitral valve function and provided adequate valuable information before and after mitral valve surgery. We conclude that live-3D-TEE can play an important role in mitral valve surgery.

  10. Making three-dimensional echocardiography more tangible: a workflow for three-dimensional printing with echocardiographic data

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    Azad Mashari MD

    2016-12-01

    Full Text Available Three-dimensional (3D printing is a rapidly evolving technology with several potential applications in the diagnosis and management of cardiac disease. Recently, 3D printing (i.e. rapid prototyping derived from 3D transesophageal echocardiography (TEE has become possible. Due to the multiple steps involved and the specific equipment required for each step, it might be difficult to start implementing echocardiography-derived 3D printing in a clinical setting. In this review, we provide an overview of this process, including its logistics and organization of tools and materials, 3D TEE image acquisition strategies, data export, format conversion, segmentation, and printing. Generation of patient-specific models of cardiac anatomy from echocardiographic data is a feasible, practical application of 3D printing technology.

  11. Three-dimensional transesophageal echocardiography: Principles and clinical applications

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    Annette Vegas

    2016-01-01

    Full Text Available A basic understanding of evolving 3D technology enables the echocardiographer to master the new skills necessary to acquire, manipulate, and interpret 3D datasets. Single button activation of specific 3D imaging modes for both TEE and transthoracic echocardiography (TTE matrix array probes include (a live, (b zoom, (c full volume (FV, and (d color Doppler FV. Evaluation of regional LV wall motion by RT 3D TEE is based on a change in LV chamber subvolume over time from altered segmental myocardial contractility. Unlike standard 2D TEE, there is no direct measurement of myocardial thickening or displacement of individual segments.

  12. The mechanism of functional tricuspid regurgitation:insight from two and three-dimensional echocardiography%功能性三尖瓣反流机制的二维及三维超声心动图探索

    Institute of Scientific and Technical Information of China (English)

    孟红; 潘世伟; 胡小鹏; 逄坤静; 李建蓉; 吕秀章; 王浩; 王燕; 李澎

    2012-01-01

    Objective To explore determinants of functional tricuspid regurgitation with twodimensional (2D) and three-dimensional (3D) echocardiography,and to provide theoretical basis for surgery treatments.Methods Fifty-six subjects with left-sided valular diseases and tricuspid regurgitation underwent 2D and 3D echocardiography examinations.The tricuspid annulus diameter,the valvular tethering height and right ventricular volume and ejection fraction were measured.Results Based on the degree of tricuspid regurgitation,the patients were grouped into mild regurgitation (group 1) and moderate or more regurgitation (group 2).Comparing the two groups by t test,the tricuspid annulus diameter,the largest distance of tricuspid valvular tethering and the end-diastolic right ventricle volume had significantly enlarged in group 2 ( P <0.01 ).And the degrees of tricuspid regurgitation had good correlations with the annulus diameter,the valvular tethering,the right ventricular volume and pulmonary artery systolic pressure.Also,the 3D echocardiography revealed there were some valvular pathologies aggravating regurgitation.Conclusions The degree of functional tricuspid regurgitation is mainly determined by the annulus dilation and pulmonary hypertension.Further more,the 3D echocardiography can give us more details of the valves.%目的 应用超声心动图探索功能性三尖瓣反流的发生机制,并为手术治疗提供理论基础.方法 对56例左心瓣膜疾病合并三尖瓣反流的患者进行超声检查,测量三尖瓣瓣环直径、瓣叶闭合高度、闭合长度、心室三维容积和射血分数.结果 根据术前反流程度将56例患者分为轻度组(组1)和中度及以上组(组2),组2的瓣环直径、闭合高度、右室容积均明显大于组1( P<0.01).与反流程度重要相关的因素分别是瓣环直径、闭合高度、右室舒张末容积、肺动脉高压.术前三维超声发现合并瓣叶器质性改变会加重反流.结论 合并左心

  13. Three-Dimensional Echocardiography of the Aortic Valve: Feasibility, Clinical Potential, and Limitations.

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    Kasprzak, Jaroslaw D.; Salustri, Alessandro; Roelandt, Jos R.T.C.; Ten Cate, Folkert J.

    1998-02-01

    OBJECTIVES: The purpose of our study was to assess the feasibility and potential clinical utility of three-dimensional echocardiography for evaluation of the aortic valve. BACKGROUND: The value of three-dimensional echocardiographic assessment of the aortic valve has not been established yet. METHODS: The study group comprised 32 patients (11 women, 21 men), mean age 56.1 (range 20-82). Seven morphologically normal valves, 5 homografts, 6 mechanical prostheses, and 14 valves of abnormal morphology were evaluated. Images were acquired during a routine multiplane transesophageal echocardiographic examination (rotational scan with 2 degrees interval, respiration, and electrocardiogram [ECG] gating) and postprocessed off-line. A selection of reconstructed cutplanes (anyplane mode) and volume-rendered three-dimensional views of aortic valve anatomy were analyzed by two observers and compared with two-dimensional echocardiography findings. RESULTS: The quality of reconstructions was scored excellent when permitting unrestricted assessment of aortic valve anatomy with optimized planimetric measurements (19 patients, 59%), adequate when aortic valve was partially visualized (7 patients, 22%), or inadequate when no assessment was possible (6 patients, 19%, including 5 with prosthetic valves). Three-dimensional echocardiography provided additional information in ten (31%) patients as compared with the two-dimensional echocardiographic findings. CONCLUSIONS: It can be concluded that three-dimensional echocardiographic reconstruction of the aortic valve is feasible, with excellent or adequate quality in 81% of patients, more frequently in native than in prosthetic valves, P < 0.05. Morphologic information additional to that provided by two-dimensional echocardiography is obtained in a significant proportion of patients.

  14. Three-dimensional Echocardiography of Right Ventricular Function Correlates with Severity of Pediatric Pulmonary Hypertension.

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    Jone, Pei-Ni; Patel, Sonali S; Cassidy, Courtney; Ivy, David Dunbar

    2016-12-01

    Right ventricular function and biomarkers of B-type natriuretic peptide (BNP) and N-Terminal pro-BNP (NT pro-BNP) are used to determine the severity of right ventricular failure and outcomes from pulmonary hypertension. Real-time three-dimensional echocardiography (3DE) is a novel quantitative measure of the right ventricle and decreases the geometric assumptions from conventional two-dimensional echocardiography (2DE). We correlated right ventricular functional measures using 2DE and single-beat 3DE with biomarkers and hemodynamics to determine the severity of pediatric pulmonary hypertension. We retrospectively evaluated 35 patients (mean age 12.67 ± 5.78 years) with established pulmonary hypertension who had echocardiograms and biomarkers on the same day. Ten out of 35 patients had hemodynamic evaluation within 3 days. 2DE evaluation included tricuspid annular plane systolic excursion (TAPSE), right ventricular myocardial performance index from tissue Doppler imaging (RV TDI MPI), and right ventricular fractional area change (FAC). Three-dimensional echocardiography evaluation included right ventricular ejection fraction (EF), end-systolic volume, and end-diastolic volume. The quality of the 3DE was graded as good, fair, or poor. Pearson correlation coefficients were utilized to evaluate between biomarkers and echocardiographic parameters and between hemodynamics and echocardiography. Three-dimensional echocardiography and FAC correlated significantly with BNP and NT pro-BNP. TAPSE and RV TDI MPI did not correlate significantly with biomarkers. 3D right ventricular EF correlated significantly with hemodynamics. Two-dimensional echocardiography did not correlate with hemodynamics. Single-beat 3DE is a noninvasive, feasible tool in the quantification of right ventricular function and maybe more accurate than conventional 2DE in evaluating severity of pulmonary hypertension. © 2016 Wiley Periodicals, Inc.

  15. Dynamic three-dimensional reconstruction of the heart by transesophageal echocardiography

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    Veiga Maria de Fátima

    1999-01-01

    Full Text Available OBJECTIVE: To evaluate echocardiography accuracy in performing and obtaining images for dynamical three-dimensional (3D reconstruction. METHODS: Three-dimensional (3D image reconstruction was obtained in 20 consecutive patients who underwent transesophageal echocardiography. A multiplanar 5 MHz transducer was used for 3D reconstruction. RESULTS: Twenty patients were studied consecutively. The following cardiac diseases were present: valvar prostheses-6 (2 mitral, 2 aortic and 2 mitral and aortic; mitral valve prolapse- 3; mitral and aortic disease - 2; aortic valve disease- 5; congenital heart disease- 3 (2 atrial septal defect- ASD - and 1 transposition of the great arteries -TGA; arteriovenous fistula- 1. In 7 patients, color Doppler was also obtained and used for 3D flow reconstruction. Twenty five cardiac structures were acquired and 60 reconstructions generated (28 of mitral valves, 14 of aortic valves, 4 of mitral prostheses, 7 of aortic prostheses and 7 of the ASD. Fifty five of 60 (91.6% reconstructions were considered of good quality by 2 independent observers. The 11 reconstructed mitral valves/prostheses and the 2 reconstructed ASDs provided more anatomical information than two dimensional echocardiography (2DE alone. CONCLUSION: 3D echocardiography using a transesophageal transducer is a feasible technique, which improves detection of anatomical details of cardiac structures, particularly of the mitral valve and atrial septum.

  16. Real-time three-dimensional speckle tracking echocardiography: technical aspects and clinical applications

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    Sorrentino R

    2016-11-01

    Full Text Available Regina Sorrentino, Roberta Esposito, Enrica Pezzullo, Maurizio Galderisi Department of Advanced Biomedical Sciences, Interdepartmental Laboratory of Cardiac Imaging, Federico II University Hospital, Naples, Italy Abstract: Three-dimensional speckle tracking echocardiography (3D STE is a novel technique for the quantification of cardiac deformation based on tracking of ultrasonic speckles in gray scale full-volume 3D images. Developments in ultrasound technologies have made 3D speckle tracking widely available. Two-dimensional echocardiography has intrinsic limitations regarding estimation of left ventricular (LV volumes, ejection fraction, and LV mechanics, due to its inherent foreshortening errors and dependency on geometric models. The development of 3D echocardiography has improved reproducibility and accuracy. Data regarding the feasibility, accuracy, and clinical applications of 3D STE are rapidly assembling. From the tracking results, 3D STE derives several parameters, including longitudinal, circumferential and radial strain, as well as a combined assessment of longitudinal and circumferential strain, termed area strain. 3D STE can also quantify LV rotational movements such as rotation, twist, and torsion. 3D STE provides a better insight on global and regional myocardial deformation. Main applications include detection of subclinical myocardial involvement in heart failure, arterial hypertension, dyssynchrony, and ischemic heart disease. Emerging areas of application include a large spectrum of heart-involving systemic conditions, such as prediction of rejection in heart transplant patients, early detection of cardiotoxicity in patients receiving chemotherapy for cancer, and deeper physiological understanding of LV contraction mechanics in different types of athletes. Aim of this review is to discuss background, technical acquisition and processing aspects as well as recognized and developing clinical applications of this emerging

  17. Three-dimensional Transesophageal Echocardiography-guided Transcathetar Closure of Ruptured Noncoronary Sinus of Valsalva Aneurysm

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    Kumar, G Anil; Parimala, P S; Jayaranganath, M; Jagadeesh, A M

    2017-01-01

    Sinus of Valsalva aneurysm accounts for only 1% of congenital cardiac anomalies. Sinus of Valsalva aneurysm can cause aortic insufficiency, coronary artery flow compromise, cardiac arrhythmia, or aneurysm rupture. Three-dimensional transesophageal echocardiography (3DTEE) represents an adjunctive tool to demonstrate the ruptured sinus of Valsalva with better delineation. We present an adult patient with rupture of noncoronary sinus of Valsalva aneurysm into the right atrium (RA). 3DTEE accurately delineated the site of rupture into the RA and showed the exact size and shape of the defect, which helped in the successful transcatheter closure of the defect with a duct occluder device. PMID:28074828

  18. Ventricular septal rupture imaged with real-time three-dimensional transesophageal echocardiography: diagnosis at a glance.

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    Squeri, Angelo; Conti, Rita; Bosi, Stefano

    2014-01-01

    Ventricular septal rupture is a rare complication of acute myocardial infarction and its diagnosis can be really challenging especially in the case of complex lesions. Echocardiography is the technique of choice for the detection of mechanical complications following myocardial infarction. The introduction of three-dimensional echocardiography offers new imaging possibilities with precise localization and easiest definition of the defect anatomy. This information is of paramount importance in the setting of a percutaneous closure procedure. We describe a case where real-time three-dimensional transesophageal echocardiography correctly defined the complex anatomy of a postmyocardial infarction septal defect with an associated pseudoaneurysm.

  19. [Congenital heart disease: Recent technical advances in three-dimensional echocardiography].

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    Karsenty, Clement; Hadeed, Khaled; Acar, Philippe

    2017-05-01

    The recent technical advances allow the use in practice of three-dimensional echocardiography in children especially through the new high frequency matrix probe. It is difficult or even impossible to hold breathing during children' acquisition so to avoid motion full volume artifact, one beat and live 3D modes are suitable. 3D echocardiography is more accurate than 2D to assess the size, location, and relationship with surrounding structures of atrial and ventricular septal defects and thus helps in the therapeutic decision. 3D echocardiography enables to guide precisely percutaneous procedure. The morphology of the valve leaflets, chordal support apparatus, papillary muscle and the annulus are particularly well described in 3D and allows assessment of the regurgitation before repair and after as well for the common valve of the atrioventricular septal defect or in the Ebstein anomaly. Complex heart diseases such as double outlet right ventricle are suitable to a tridimensional assessment to plan surgical strategy. 3D printing, fusion imaging in cathlab and automated volume quantification embody recent innovations of new techniques in congenital heart disease. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  20. Automated Assessment of Right Ventricular Volumes and Function Using Three-Dimensional Transesophageal Echocardiography.

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    Nillesen, Maartje M; van Dijk, Arie P J; Duijnhouwer, Anthonie L; Thijssen, Johan M; de Korte, Chris L

    2016-02-01

    Assessment of right ventricular (RV) function is known to be of diagnostic value in patients with RV dysfunction. Because of its complex anatomic shape, automated determination of the RV volume is difficult and strong reliance on geometric assumptions is not desired. A method for automated RV assessment was developed using three-dimensional (3-D) echocardiography without relying on a priori knowledge of the cardiac anatomy. A 3-D adaptive filtering technique that optimizes the discrimination between blood and myocardium was applied to facilitate endocardial border detection. Filtered image data were incorporated in a segmentation model to automatically detect the endocardial RV border. End-systolic and end-diastolic RV volumes, as well as ejection fraction, were computed from the automatically segmented endocardial surfaces and compared against reference volumes manually delineated by two expert cardiologists. The results reported good performance in terms of correlation and agreement with the results from the reference volumes.

  1. Incremental Value of Three-Dimensional Transesophageal Echocardiography over the Two-Dimensional Technique in the Assessment of a Thrombus in Transit through a Patent Foramen Ovale.

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    Thind, Munveer; Ahmed, Mustafa I; Gok, Gulay; Joson, Marisa; Elsayed, Mahmoud; Tuck, Benjamin C; Townsley, Matthew M; Klas, Berthold; McGiffin, David C; Nanda, Navin C

    2015-05-01

    We report a case of a right atrial thrombus traversing a patent foramen ovale into the left atrium, where three-dimensional transesophageal echocardiography provided considerable incremental value over two-dimensional transesophageal echocardiography in its assessment. As well as allowing us to better spatially characterize the thrombus, three-dimensional transesophageal echocardiography provided a more quantitative assessment through estimation of total thrombus burden.

  2. Magnetic structure of two- and three-dimensional supramolecular compounds

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    Decurtins, S.; Schmalle, H.W.; Pellaux, R. [Zurich Univ. (Switzerland); Fischer, P.; Fauth, F. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Ouladdiaf, B. [Institut Max von Laue - Paul Langevin, 75 - Paris (France)

    1997-09-01

    Supramolecular chiral networks of oxalato-bridged transition metals show either two- or three-dimensional structural features. The magnetic structures of such compounds have been investigated by means of elastic neutron powder diffraction. (author) 2 figs., 2 refs.

  3. Magnetic structure of two- and three-dimensional supramolecular compounds

    Energy Technology Data Exchange (ETDEWEB)

    Decurtins, S.; Schmalle, H.W.; Pellaux, R. [Zurich Univ. (Switzerland); Fischer, P.; Fauth, F. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Ouladdiaf, B. [Institut Max von Laue - Paul Langevin, 75 - Paris (France)

    1997-09-01

    Supramolecular chiral networks of oxalato-bridged transition metals show either two- or three-dimensional structural features. The magnetic structures of such compounds have been investigated by means of elastic neutron powder diffraction. (author) 2 figs., 2 refs.

  4. The additional value of three-dimensional transesophageal echocardiography in complex aortic prosthetic heart valve endocarditis.

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    Tanis, Wilco; Teske, Arco J; van Herwerden, Lex A; Chamuleau, Steven; Meijboom, Folkert; Budde, Ricardo P J; Cramer, Maarten-Jan

    2015-01-01

    Two-dimensional transthoracic and transesophageal echocardiography (2DTTE and 2DTEE) may fail to detect signs of prosthetic heart valve (PHV) endocarditis due to acoustic shadowing. Three-dimensional (3D) TEE may have additional value; however, data are scarce. This study was performed to investigate the additional value of 3DTEE for the detection of aortic PHV endocarditis and the extent of the disease process. Retrospective analysis of complex aortic PHV endocarditis cases that underwent 2DTTE, 2DTEE, and 3DTEE before surgery. Echocardiograms were individually assessed by 2 cardiologists blinded for the outcome. Surgical and pathological inspection served as the reference standard for vegetations and peri-annular extensions (abscesses/mycotic aneurysms). To determine if the proximal coronary arteries were involved in the inflammatory process as well, computed tomography angiography findings were added to reference standard. Fifteen aortic PHV endocarditis cases were identified. According to the reference standard, all 15 cases had peri-annular extensions, 13 of which had a close relationship with the proximal right and/or left coronary artery. In 6 of 15 patients, a vegetation was present. Combined 2DTTE/TEE missed 1/6 vegetations and 1/15 peri-annular extensions. After addition of 3DTEE, all vegetations (6/6) and peri-annular extensions (15/15) were detected, without adding false positives. Compared to 2DTEE, in 3/15 cases, 3DTEE resulted in better delineation of the anatomical relationship of the proximal coronary arteries to the peri-annular extensions. As a result, 3DTEE had an additional value in 5/15 cases. In complex aortic, PHV endocarditis 3DTEE may have additional value compared to 2D echocardiography. © 2014, Wiley Periodicals, Inc.

  5. Semiautomated biventricular segmentation in three-dimensional echocardiography by coupled deformable surfaces.

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    Bersvendsen, Jørn; Orderud, Fredrik; Lie, Øyvind; Massey, Richard John; Fosså, Kristian; Estépar, Raúl San José; Urheim, Stig; Samset, Eigil

    2017-04-01

    With the advancement of three-dimensional (3-D) real-time echocardiography in recent years, automatic creation of patient specific geometric models is becoming feasible and important in clinical decision making. However, the vast majority of echocardiographic segmentation methods presented in the literature focus on the left ventricle (LV) endocardial border, leaving segmentation of the right ventricle (RV) a largely unexplored problem, despite the increasing recognition of the RV's role in cardiovascular disease. We present a method for coupled segmentation of the endo- and epicardial borders of both the LV and RV in 3-D ultrasound images. To solve the segmentation problem, we propose an extension of a successful state-estimation segmentation framework with a geometrical representation of coupled surfaces, as well as the introduction of myocardial incompressibility to regularize the segmentation. The method was validated against manual measurements and segmentations in images of 16 patients. Mean absolute distances of [Formula: see text], [Formula: see text], and [Formula: see text] between the proposed and reference segmentations were observed for the LV endocardium, RV endocardium, and LV epicardium surfaces, respectively. The method was computationally efficient, with a computation time of [Formula: see text].

  6. Measurement of the aortic annulus size by real-time three-dimensional transesophageal echocardiography.

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    Jánosi, Rolf Alexander; Kahlert, Philipp; Plicht, Björn; Wendt, Daniel; Eggebrecht, Holger; Erbel, Raimund; Buck, Thomas

    2011-04-01

    We sought to determine the level of agreement and the reproducibility of two-dimensional (2D) transthoracic (2D-TTE), 2D transesophageal (2D-TEE) and real-time three-dimensional (3D) transesophageal echocardiography (RT3D-TEE) for measurement of aortic annulus size in patients referred for transcatheter aortic valve implantation (TAVI). Accurate preoperative assessment of the dimensions of the aortic annulus is critical for patient selection and successful implantation in those undergoing TAVI for severe aortic stenosis (AS). Annulus size was measured using 2D-TTE, 2D-TEE and RT3D-TEE in 105 patients with severe AS referred for TAVI. Agreement between echocardiographic methods and interobserver variability was assessed using the Bland-Altman method and regression analysis, respectively. The mean aortic annuli were 21,7 ± 3 mm measured with 2D-TTE, 22,6 ± 2,8 mm with 2D-TEE and 22,3 ± 2,9 mm with RT3D-TEE. The results showed a small but significant mean difference and a strong correlation between the three measurement techniques (2D-TTE vs. 2D-TEE mean difference 0,84 ± 1,85 mm, r = 0,8, p annulus measured by 2D-TTE, 2D-TEE and RT3D-TEE. Thus, in patients referred for TAVI, the echocardiographic method used may have an impact on TAVI strategy.

  7. Three-dimensional echocardiography in congenital heart disease : an expert consensus document from the European Association of Cardiovascular Imaging and the American Society of Echocardiography

    NARCIS (Netherlands)

    Simpson, John; Lopez, Leo; Acar, Philippe; Friedberg, Mark; Khoo, Nee; Ko, Helen; Marek, Jan; Marx, Gerald; McGhie, Jackie; Meijboom, Folkert|info:eu-repo/dai/nl/136537367; Roberson, David; Van den Bosch, Annemien; Miller, Owen; Shirali, Girish

    2016-01-01

    Three-dimensional echocardiography (3DE) has become important in the management of patients with congenital heart disease (CHD), particularly with pre-surgical planning, guidance of catheter intervention, and functional assessment of the heart. 3DE is increasingly used in children because of good

  8. Three-dimensional Echocardiography in Congenital Heart Disease : An Expert Consensus Document from the European Association of Cardiovascular Imaging and the American Society of Echocardiography

    NARCIS (Netherlands)

    Simpson, John; Lopez, Leo; Acar, Philippe; Friedberg, Mark K; Khoo, Nee S; Ko, Helen; Marek, Jan; Marx, Gerald; McGhie, Jackie S; Meijboom, Folkert|info:eu-repo/dai/nl/136537367; Roberson, David; van den Bosch, Annemien E; Miller, Owen; Shirali, Girish

    2017-01-01

    Three-dimensional echocardiography (3DE) has become important in the management of patients with congenital heart disease (CHD), particularly with pre-surgical planning, guidance of catheter intervention, and functional assessment of the heart. 3DE is increasingly used in children because of good

  9. Three-dimensional Echocardiography in Congenital Heart Disease : An Expert Consensus Document from the European Association of Cardiovascular Imaging and the American Society of Echocardiography

    NARCIS (Netherlands)

    Simpson, John; Lopez, Leo; Acar, Philippe; Friedberg, Mark K; Khoo, Nee S; Ko, Helen; Marek, Jan; Marx, Gerald; McGhie, Jackie S; Meijboom, Folkert; Roberson, David; van den Bosch, Annemien E; Miller, Owen; Shirali, Girish

    2017-01-01

    Three-dimensional echocardiography (3DE) has become important in the management of patients with congenital heart disease (CHD), particularly with pre-surgical planning, guidance of catheter intervention, and functional assessment of the heart. 3DE is increasingly used in children because of good ac

  10. Three-dimensional echocardiography in congenital heart disease : an expert consensus document from the European Association of Cardiovascular Imaging and the American Society of Echocardiography

    NARCIS (Netherlands)

    Simpson, John; Lopez, Leo; Acar, Philippe; Friedberg, Mark; Khoo, Nee; Ko, Helen; Marek, Jan; Marx, Gerald; McGhie, Jackie; Meijboom, Folkert|info:eu-repo/dai/nl/136537367; Roberson, David; Van den Bosch, Annemien; Miller, Owen; Shirali, Girish

    2016-01-01

    Three-dimensional echocardiography (3DE) has become important in the management of patients with congenital heart disease (CHD), particularly with pre-surgical planning, guidance of catheter intervention, and functional assessment of the heart. 3DE is increasingly used in children because of good ac

  11. Three-dimensional echocardiography in congenital heart disease : an expert consensus document from the European Association of Cardiovascular Imaging and the American Society of Echocardiography

    NARCIS (Netherlands)

    Simpson, John; Lopez, Leo; Acar, Philippe; Friedberg, Mark; Khoo, Nee; Ko, Helen; Marek, Jan; Marx, Gerald; McGhie, Jackie; Meijboom, Folkert; Roberson, David; Van den Bosch, Annemien; Miller, Owen; Shirali, Girish

    2016-01-01

    Three-dimensional echocardiography (3DE) has become important in the management of patients with congenital heart disease (CHD), particularly with pre-surgical planning, guidance of catheter intervention, and functional assessment of the heart. 3DE is increasingly used in children because of good ac

  12. The Early Variation of Left Ventricular Strain after Aortic Valve Replacement by Three-Dimensional Echocardiography.

    Directory of Open Access Journals (Sweden)

    Yongle Chen

    Full Text Available Aortic stenosis (AS and aortic incompetence (AI are common aortic valve diseases. Both may deteriorate into irreversible myocardial dysfunction and will increase the risk of sudden death. In this study, we aimed to investigate the early variation trend of left ventricular function by three-dimensional speckle tracking echocardiography (3D-STE in the patients who underwent cardiac surgeries for aortic valve disease. Twenty patients with severe aortic AS and 16 patients with severe AI were enrolled. All of them underwent the aortic valve replacement (AVR procedures. The patients' global longitudinal strain (GLS and global circumferential strain (GCS were evaluated by 3D-STE before surgery and at 1 week after surgery. In addition, GLS and GCS were followed at 1 month as well as 3 months after AVR. In AS patients, the GCS after AVR altered little both at 1 week (p = 0.562 and at 1 month (p = 0.953 compared with the data before the surgery. And it increased significantly at 3 months of follow-up observation compared to that before AVR (p<0.05. Meanwhile, GLS increased progressively after AVR and improved significantly at 3 months after surgery (p<0.05. For the AI patients, GLS as well as GCS decreased at 1 week after AVR compared to those data at baseline (p<0.05. However, these two parameters recovered at 1 month after AVR. Furthermore, GLS and GCS improved significantly at 3 months after the surgery (p<0.05. Therefore, both GLS and GCS were influenced by AVR and would be improved at 3 months after surgery both in AS patients or AI patients. GLS and GCS can be finely evaluated by 3D-STE, and they are helpful to determine the variation tendency of left ventricular function in patients with AVR.

  13. Evaluation of Right Ventricular Volume and Systolic Function by Real-time Three-dimensional Echocardiography

    Institute of Scientific and Technical Information of China (English)

    WANG Jing; WANG Xinfang; XIE Mingxing; YANG Ya; LV Qing; YANG Ying; WANG Liangyu

    2005-01-01

    The optimal plane for measurement of the right ventricular (RV) volumes by real-time three-dimensional echocardiography (RT3DE) was determined and the feasibility and accuracy of RT3DE in studying RV systolic function was assessed. RV "Full volume" images were acquired by RT3DE in 22 healthy subjects. RV end-diastolic volumes (RVEDV) and end-systolic volumes (RVESV) were outlined using apical biplane, 4-plane, 8-plane, 16-plane offline separately. RVSV and RVEF were calculated. Meanwhile tricuspid annual systolic excursion (TASE) was measured by M-mode echo. LVSV was outlined by 2-D echo according to the biplane Simpsons rule. The results showed: (1) There was a good correlation between RVSV measured from series planes and LVSV from 2-D echo (r=0.73; r=0.69; r=0.63; r=0.66, P<0.25-0. 0025); (2) There were significant differences between RVEDV in biplane and those in 4-, 8-, 16-plane (P<0. 001). There was also difference between RV volume in 4-plane and that in 8-plane (P<0.05), but there was no significant difference between RV volume in 8-plane and that in 16-plane (P>0.05); (3) Inter-observers and intro-observers variability analysis showed that there were close agreements and relations for RV volumes (r=0. 986, P<0. 001; r=0.93, P<0. 001); (4) There was a significantly positive correlation of TASE to RVSV and RVEF from RT3DE (r=0.83; r=0.90). So RV volume measures with RT3DE are rapid, accurate and reproducible. In view of RVs complex shape,apical 8-plane method is better in clinical use. It may allow early detection of RV systolic function.

  14. Two- and Three-Dimensional Simulations of Asteroid Ocean Impacts

    Science.gov (United States)

    Gisler, G.; Weaver, R. P.; Mader, C. L.; Gittings, M. L.

    2003-01-01

    We have performed a series of two-dimensional and three-dimensional simulations of asteroid impacts into an ocean using the SAGE code from Los Alamos National Laboratory and Science Applications International Corporation. The SAGE code is a compressible Eulerian hydrodynamics code using continuous adaptive mesh refinement for following discontinuities with a fine grid while treating the bulk of the simulation more coarsely. We have used tabular equations of state for the atmosphere, water, the oceanic crust, and the mantle. In two dimensions, we simulated asteroid impactors moving at 20 km/s vertically through an exponential atmosphere into a 5 km deep ocean. The impactors were composed of mantle material (3.32 g/cc) or iron (7.8 g/cc) with diameters from 250m to 10 km. In our three-dimensional runs we simulated asteroids of 1 km diameter composed of iron moving at 20 km/s at angles of 45 and 60 degrees from the vertical. All impacts, including the oblique ones, produce large underwater cavities with nearly vertical walls followed by a collapse starting from the bottom and subsequent vertical jetting. Substantial amounts of water are vaporized and lofted high into the atmosphere. In the larger impacts, significant amounts of crustal and even mantle material are lofted as well. Tsunamis up to a kilometer in initial height are generated by the collapse of the vertical jet. These waves are initially complex in form, and interact strongly with shocks propagating through the water and the crust. The tsunami waves are followed out to 100 km from the point of impact. Their periods and wavelengths show them to be intermediate type waves, and not (in general) shallow-water waves. At great distances, the waves decay faster than the inverse of the distance from the impact point, ignoring sea-floor topography. For all impactors smaller than about 2 km diameter, the impacting body is highly fragmented and its remains lofted into the stratosphere with the water vapor and crustal

  15. TWO- AND THREE-DIMENSIONAL SIMULATIONS OF ASTEROID OCEAN IMPACTS

    Directory of Open Access Journals (Sweden)

    Michael Gittings

    2003-01-01

    Full Text Available We have performed a series of two-dimensional and three-dimensional simulations of asteroid impacts into an ocean using the SAGE code from Los Alamos National Laboratory and Science Applications International Corporation. The SAGE code is a compressible Eulerian hydrodynamics code using continuous adaptive mesh refinement for following discontinuities with a fine grid while treating the bulk of the simulation more coarsely. We have used realistic equations of state for the atmosphere, sea water, the oceanic crust, and the mantle. In two dimensions, we simulated asteroid impactors moving at 20 km/s vertically through an exponential atmosphere into a 5 km deep ocean. The impactors were composed of mantle material (3.32 g/cc or iron (7.8 g/cc with diameters from 250m to 10 km. In our three-dimensional runs we simulated asteroids of 1 km diameter composed of iron moving at 20 km/s at angles of 45 and 60 degrees from the vertical. All impacts, including the oblique ones, produce a large underwater cavities with nearly vertical walls followed by a collapse starting from the bottom and subsequent vertical jetting. Substantial amounts of water are vaporized and lofted high into the atmosphere. In the larger impacts, significant amounts of crustal and even mantle material are lofted as well. Tsunamis up to a kilometer in initial height are generated by the collapse of the vertical jet. These waves are initially complex in form, and interact strongly with shocks propagating through the water and the crust. The tsunami waves are followed out to 100 km from the point of impact. Their periods and wavelengths show them to be intermediate type waves, and not (in general shallow-water waves. At great distances, the waves decay as the inverse of the distance from the impact point, ignoring sea-floor topography. For all impactors smaller than about 2 km diameter, the impacting body is highly fragmented and its remains lofted into the stratosphere with the water

  16. Right heart function assessment with real-time three-dimensional echocardiography before and after atrial septal defect surgery

    Institute of Scientific and Technical Information of China (English)

    Hua Zhao; Yi-Min Fu; Yong-Mei Jia

    2016-01-01

    Objective:To study the clinical value of right heart function assessment with real-time three-dimensional echocardiography before and after atrial septal defect surgery. Methods:Patients with atrial septal defect who received transcatheter closure in our hospital were selected for study and divided into non-pulmonary hypertension group and pulmonary hypertension group according to pulmonary artery systolic pressure (PASP), real-time three-dimensional echocardiography was conducted before and after operation, and right ventricular end-diastolic volume (RVEDV), right ventricular end-systolic volume (RVESV), right ventricular stroke volume (RVSV), right ventricular ejection fraction (RVEF) and right ventricular cardiac output (RVCO) were calculated;serum was collected, and brain natriuretic peptide (BNP), atrial natriuretic peptide (ANP), angiotensin I (AngI), angiotensin II (AngII) and endothelin (ET) contents were detected. Results:After operation, RVEDV, RVESV, RVSV, RVEF and RVCO as well as serum BNP, ANP, AngI, AngII and ET contents of both groups were lower than those before treatment;RVEDV, RVESV, RVSV, RVEF and RVCO were positively correlated with contents of BNP, ANP, AngI, AngII and ET. Conclusions:Using real-time three-dimensional echocardiography before and after atrial septal defect surgery can accurately assess right heart function, and it has good correlation with right heart volume load and pulmonary circulation blood flow.

  17. Left ventricular myocardial function in hemodialysis and nondialysis uremia patients: a three-dimensional speckle-tracking echocardiography study.

    Directory of Open Access Journals (Sweden)

    Ran Chen

    Full Text Available BACKGROUND: Several studies have demonstrated that uremic patients who have preserved left ventricular ejection fraction (LVEF could still have the potential for systolic dysfunction. The aim of this study was to assess the differences between the left ventricular (LV myocardial function in hemodialysis and nondialysis uremic patients based on three-dimensional speckle-tracking echocardiography. METHODS: The study population consisted of 35 maintenance hemodialysis patients (the hemodialysis group, 30 uremic patients who were hospitalized for the creation of a primary arteriovenous fistula (the nondialysis group, and 32 healthy volunteers. All of the patients had normal left ventricular ejection fractions (i.e., 55% or greater. Three-dimensional speckle tracking echocardiography was performed to assess the left ventricle's global three-dimensional strain, regional longitudinal strain, circumferential strain, and radial strain. RESULTS: The left ventricular regional longitudinal strain, radial strain, circumferential strain, and global three-dimensional strain were significantly decreased in the nondialysis patients compared with the other two groups (all, P<0.001. However, the three-dimensional strain and the regional longitudinal strain were lower in the hemodialysis patients than in the controls (P<0.01. In the hemodialysis patients and the control group, the longitudinal strain, circumferential strain, and radial strain were higher at the apical level than they were at the basal level and midlevels. A multivariate linear regression analysis showed that the blood urea nitrogen and creatinine levels were independently associated with the values of the global three-dimensional strain (β = -0.217, P = 0.000; β = -0.243, P = 0.011, respectively and the longitudinal strain (β = -0.154, P = 0.032; β = -0.188, P = 0.029, respectively. CONCLUSIONS: Three-dimensional speckle-tracking echocardiography may detect

  18. Real-time three-dimensional myocardial contrast echocardiography in assessment of myocardial perfusion defects

    Institute of Scientific and Technical Information of China (English)

    CHEN Li-xin 陈立新; YANG Ying 杨颖; FEI Hong-wen 费洪文; WANG Liang-yu 王良玉; WANG Xin-fang 王新房; Navin C Nanda; Andrew P Miller; XIE Ming-xing 谢明星; ZHUANG Lei 庄磊; YANG Ya 杨娅; WANG Jing 王静; HUANG Run-qing 黄润青

    2004-01-01

    Background Both real-time three-dimensional echocardiography (RT3DE) and myocardial contrast echocardiography (MCE) are novel imaging techniques. The purpose of this study was to confirm the feasibility and accuracy of RT3DE combined with MCE for quantitative evaluation of myocardial perfusion defects.Methods Thirteen dogs underwent ligation of the left anterior descending artery (LAD, n=6) or distal branch of the left circumflex artery (LCX, n=7) under general anaesthesia. Three to four ml of a perfluoropropane (C3F8) microbubble contrast agent was injected intravenously to assess the resulting myocardial perfusion defects with a commercially available Philips SONOS-7500 ultrasound system. After removal of the dog hearts, Evans blue dye was injected via the left and right coronary arteries to stain the myocardium at risk. In vitro anatomic measurements of myocardial mass after removal of the animals' hearts were used as controls.Results Left ventricular (LV) mass determined by RT3DE ranged 36.7-68.9 g [mean, (54.6±9.6) g] before coronary artery ligation, and correlated highly (r=0.99) with in vitro measurement of LV mass [range, 38.9-71.1 g; mean, (55.6±9.3) g]. There was no significant difference between RT3DE and in vitro measurements of LV mass [range, 36.7-68.9 g; mean, (51.3±12.5) g. Or range, 38.9-71.1 g; mean, (53.7±12.3) g, respectively] and under-perfused mass [range, 0-21.4 g; mean, (12.0±6.9) g. Or range, 0-19.8 g; mean, (10.8±6.3) g, respectively] after the LAD ligation (P>0.05). Likewise, no significant difference was present between RT3DE and in vitro measurements of LV mass [range, 50.1-65.4 g; mean, (57.5±5.9) g. Or range, 51.5-65.8 g; mean, (57.3±6.4) g, respectively] and under-perfused mass [range, 0-25.6 g; mean, (13.3±9.6) g. Or range, 0-22.7 g; mean, (12.8±8.1) g, respectively] after the LCX ligation (P>0.05). For all the animals with coronary ligation, LV mass measured by RT3DE ranged 35.9-68.6 g [mean, (54.8±10.0) g] and there was

  19. QUANTITATIVE ASSESSMENT OF MYOCARDIAL PERFUSION DEFECTS WITH REAL-TIME THREE-DIMENSIONAL MYOCARDIAL CONTRAST ECHOCARDIOGRAPHY

    Institute of Scientific and Technical Information of China (English)

    Lei Zhuang; Ming-xing Xie; Wei-juan Wang; Xiang-xin Yang; Tao Liu

    2006-01-01

    Objective To evaluate the feasibility and accuracy of measurement of myocardial perfusion defects with intravenous contrast-enhanced real-time three-dimensional echocardiography (CE-RT3 DE).Methods RT3DE was performed in 21 open-chest mongrel dogs undergoing acute ligation of the left anterior descending artery (LAD,n=14) or distal branch of the left circumflex artery (LCX,n=7).A perfluorocarbon microbubble contrast agent was injected intravenously to assess the resulting myocardial perfusion defects with Philips Sonos7500 ultrasound system. Evans blue dye was injected into the occluded coronary artery for subsequent anatomic identification of underperfused myocardium. In vitro anatomic measurement of myocardial mass after removal of the animal's heart was regarded as the control. Blinded off-line calculation of left ventricular mass and perfusion defect mass from RT3DE images were performed using an interactive aided-manual tracing technique.Results Total left ventricular (LV) myocardial mass ranged from 38. 9 to78.5 (mean±SD: 60.0±10.1)g. The mass of perfusion defect ranged from 0 to 21.4 (mean±SD: 12.0±5.0) g or 0 to 27% of total LV mass (mean±SD: 19%±6%). The RT3DE estimation of total LV mass (mean±SD: 59.8±9.9 g) strongly correlated with the anatomic measurement (r=0.98; y=2.01+0.96x). The CE-RT3DE calculation of the mass of underperfused myocardium (mean±SD: 12.3±5.3 g) also strongly correlated with the anatomic measurement (r=0.96; y=0.10+1.04x) and when expressed as percentage of total LV mass (r=0.95; y=-0.20+1.04x).Conclusions RT3DE with myocardial contrast opacification could accurately estimate underperfused myocardial mass in dogs of acute coronary occlusion and would play an important role in quantitative assessment of myocardial perfusion defects in patients with coronary artery disease.

  20. Dynamic three-dimensional echocardiography combined with semi-automated border detection offers advantages for assessment of resynchronization therapy

    Directory of Open Access Journals (Sweden)

    Voormolen Marco M

    2003-10-01

    Full Text Available Abstract Simultaneous electrical stimulation of both ventricles in patients with interventricular conduction disturbance and advanced heart failure improves hemodynamics and results in increased exercise tolerance, quality of life. We have developed a novel technique for the assessment and optimization of resynchronization therapy. Our approach is based on transthoracic dynamic three-dimensional (3D echocardiography and allows determination of the most delayed contraction site of the left ventricle (LV together with global LV function data. Our initial results suggest that fast reconstruction of the LV is feasible for the selection of the optimal pacing site and allows identifying LV segments with dyssynchrony.

  1. Echocardiography derived three-dimensional printing of normal and abnormal mitral annuli

    Directory of Open Access Journals (Sweden)

    Feroze Mahmood

    2014-01-01

    Full Text Available Aims and Objectives: The objective of this study was to assess the clinical feasibility of using echocardiographic data to generate three-dimensional models of normal and pathologic mitral valve annuli before and after repair procedures. Materials and Methods: High-resolution transesophageal echocardiographic data from five patients was analyzed to delineate and track the mitral annulus (MA using Tom Tec Image-Arena software. Coordinates representing the annulus were imported into Solidworks software for constructing solid models. These solid models were converted to stereolithographic (STL file format and three-dimensionally printed by a commercially available Maker Bot Replicator 2 three-dimensional printer. Total time from image acquisition to printing was approximately 30 min. Results: Models created were highly reflective of known geometry, shape and size of normal and pathologic mitral annuli. Post-repair models also closely resembled shapes of the rings they were implanted with. Compared to echocardiographic images of annuli seen on a computer screen, physical models were able to convey clinical information more comprehensively, making them helpful in appreciating pathology, as well as post-repair changes. Conclusions: Three-dimensional printing of the MA is possible and clinically feasible using routinely obtained echocardiographic images. Given the short turn-around time and the lack of need for additional imaging, a technique we describe here has the potential for rapid integration into clinical practice to assist with surgical education, planning and decision-making.

  2. Echocardiography derived three-dimensional printing of normal and abnormal mitral annuli.

    Science.gov (United States)

    Mahmood, Feroze; Owais, Khurram; Montealegre-Gallegos, Mario; Matyal, Robina; Panzica, Peter; Maslow, Andrew; Khabbaz, Kamal R

    2014-01-01

    The objective of this study was to assess the clinical feasibility of using echocardiographic data to generate three-dimensional models of normal and pathologic mitral valve annuli before and after repair procedures. High-resolution transesophageal echocardiographic data from five patients was analyzed to delineate and track the mitral annulus (MA) using Tom Tec Image-Arena software. Coordinates representing the annulus were imported into Solidworks software for constructing solid models. These solid models were converted to stereolithographic (STL) file format and three-dimensionally printed by a commercially available Maker Bot Replicator 2 three-dimensional printer. Total time from image acquisition to printing was approximately 30 min. Models created were highly reflective of known geometry, shape and size of normal and pathologic mitral annuli. Post-repair models also closely resembled shapes of the rings they were implanted with. Compared to echocardiographic images of annuli seen on a computer screen, physical models were able to convey clinical information more comprehensively, making them helpful in appreciating pathology, as well as post-repair changes. Three-dimensional printing of the MA is possible and clinically feasible using routinely obtained echocardiographic images. Given the short turn-around time and the lack of need for additional imaging, a technique we describe here has the potential for rapid integration into clinical practice to assist with surgical education, planning and decision-making.

  3. Three-dimensional Echocardiography in Congenital Heart Disease: An Expert Consensus Document from the European Association of Cardiovascular Imaging and the American Society of Echocardiography.

    Science.gov (United States)

    Simpson, John; Lopez, Leo; Acar, Philippe; Friedberg, Mark K; Khoo, Nee S; Ko, H Helen; Marek, Jan; Marx, Gerald; McGhie, Jackie S; Meijboom, Folkert; Roberson, David; Van den Bosch, Annemien; Miller, Owen; Shirali, Girish

    2017-01-01

    Three-dimensional echocardiography (3DE) has become important in the management of patients with congenital heart disease (CHD), particularly with pre-surgical planning, guidance of catheter intervention, and functional assessment of the heart. 3DE is increasingly used in children because of good acoustic windows and the non-invasive nature of the technique. The aim of this paper is to provide a review of the optimal application of 3DE in CHD including technical considerations, image orientation, application to different lesions, procedural guidance, and functional assessment. Copyright © 2016 European Society of Cardiology. Published by Elsevier Inc. All rights reserved.

  4. Real time three-dimensional transthoracic echocardiography of ruptured left sinus of Valsalva aneurysm to left ventricle.

    Science.gov (United States)

    Kharwar, Rajiv Bharat; Narain, Varun Shankar; Sethi, Rishi

    2013-11-01

    Aneurysms arising from the sinus of Valsalva are a rare cardiac defect that can present with various signs and symptoms, and if not diagnosed and treated rapidly can lead to fatal outcomes. Unruptured aneurysms are usually asymptomatic and found incidentally during diagnostic studies. More commonly, aneurysm of sinus of Valsalva is detected after the occurrence of rupture. Echocardiography has become the investigative tool of choice for this condition, not only for diagnosis but also for quantification of severity. We hereby report a rare case of a 15-year-old patient presenting with complaints of effort dyspnea and palpitations. Two-dimensional transthoracic echocardiography (TTE) showed aneurysmal dilatation of left sinus of Valsalva which had ruptured into the left ventricle. Also, there was an intimal flap within the sinus of Valsalva aneurysm. The anatomical relationship between the aorta, aneurysm, and the left ventricle as well as the intimal flap within the aneurysm was clearly delineated with the help of three-dimensional TTE. After confirmation of the diagnosis with multidetector computed tomography, patient underwent successful surgical repair of the defect.

  5. Three-dimensional Speckle Tracking Echocardiography in Light Chain Cardiac Amyloidosis: Examination of Left and Right Ventricular Myocardial Mechanics Parameters.

    Science.gov (United States)

    Urbano-Moral, Jose Angel; Gangadharamurthy, Dakshin; Comenzo, Raymond L; Pandian, Natesa G; Patel, Ayan R

    2015-08-01

    The study of myocardial mechanics has a potential role in the detection of cardiac involvement in patients with amyloidosis. This study aimed to characterize 3-dimensional-speckle tracking echocardiography-derived left and right ventricular myocardial mechanics in light chain amyloidosis and examine their relationship with brain natriuretic peptide. In patients with light chain amyloidosis, left ventricular longitudinal and circumferential strain (n=40), and right ventricular longitudinal strain and radial displacement (n=26) were obtained by 3-dimensional-speckle tracking echocardiography. Brain natriuretic peptide levels were determined. All myocardial mechanics measurements showed differences when compared by brain natriuretic peptide level tertiles. Left and right ventricular longitudinal strain were highly correlated (r=0.95, P<.001). Left ventricular longitudinal and circumferential strain were reduced in patients with cardiac involvement (-9±4 vs -16±2; P<.001, and -24±6 vs -29±4; P=.01, respectively), with the most prominent impairment at the basal segments. Right ventricular longitudinal strain and radial displacement were diminished in patients with cardiac involvement (-9±3 vs -17±3; P<.001, and 2.7±0.8 vs 3.8±0.3; P=.002). On multivariate analysis, left ventricular longitudinal strain was associated with the presence of cardiac involvement (odds ratio = 1.6; 95% confidence interval, 1.04 to 2.37; P=.03) independent of the presence of brain natriuretic peptide and troponin I criteria for cardiac amyloidosis. Three-dimensional-speckle tracking echocardiography-derived left and right ventricular myocardial mechanics are increasingly altered as brain natriuretic peptide increases in light chain amyloidosis. There appears to be a strong association between left ventricular longitudinal strain and cardiac involvement, beyond biomarkers such as brain natriuretic peptide and troponin I. Copyright © 2015 Sociedad Española de Cardiología. Published by

  6. Three-dimensional echocardiography in congenital heart disease: an expert consensus document from the European Association of Cardiovascular Imaging and the American Society of Echocardiography.

    Science.gov (United States)

    Simpson, John; Lopez, Leo; Acar, Philippe; Friedberg, Mark; Khoo, Nee; Ko, Helen; Marek, Jan; Marx, Gerald; McGhie, Jackie; Meijboom, Folkert; Roberson, David; Van den Bosch, Annemien; Miller, Owen; Shirali, Girish

    2016-10-01

    Three-dimensional echocardiography (3DE) has become important in the management of patients with congenital heart disease (CHD), particularly with pre-surgical planning, guidance of catheter intervention, and functional assessment of the heart. 3DE is increasingly used in children because of good acoustic windows and the non-invasive nature of the technique. The aim of this paper is to provide a review of the optimal application of 3DE in CHD including technical considerations, image orientation, application to different lesions, procedural guidance, and functional assessment. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

  7. Molecular dynamics study of two- and three-dimensional classical fluids using double Yukawa potential

    Indian Academy of Sciences (India)

    Y Pathania; P K Ahluwalla

    2005-09-01

    We have carried out a molecular dynamics simulation of two- and three- dimensional double Yukawa fluids near the triple point. We have compared some of the static and dynamic correlation functions with those of Lennard{Jones, when parameters occurring in double Yukawa potential are chosen to fit Lennard-Jones potential. The results are in good agreement. However, when repulsive and attractive parameters occurring in double Yukawa potential are varied, we found distinct differences in static and dynamic correlation functions. We have also compared the two-dimensional correlation functions with those of three-dimensional to study the effect of dimensionality, near the triple point region.

  8. Regularized lattice Bhatnagar-Gross-Krook model for two- and three-dimensional cavity flow simulations.

    Science.gov (United States)

    Montessori, A; Falcucci, G; Prestininzi, P; La Rocca, M; Succi, S

    2014-05-01

    We investigate the accuracy and performance of the regularized version of the single-relaxation-time lattice Boltzmann equation for the case of two- and three-dimensional lid-driven cavities. The regularized version is shown to provide a significant gain in stability over the standard single-relaxation time, at a moderate computational overhead.

  9. Thermal field diffusion in one, two and three-dimensional half space

    Directory of Open Access Journals (Sweden)

    Cividjian Grigore A.

    2011-01-01

    Full Text Available The diffusion of suddenly occurring local high temperature in homogeneous half-infinite space is studied in the cases of one, two and three-dimensional half space. Comparison of the three cases is made. Applications of theoretically analyzed models are suggested. Errors induced by assumptions are evaluated.

  10. Segregation of Granular Material in Two and Three-Dimensional Units

    Indian Academy of Sciences (India)

    Sandhya Mishra; Ankit Namdev; Munindra Bisen; Jeeshan Ahmad; Vishal Mishra

    2016-10-01

    Segregation of particulate materials in mixtures is controlledby differences in density, shape, and size. Experiments on segregationwere performed in two and three-dimensional demonstrationunits. The results conclusively indicated that the segregationof solids is affected by the shape, size and density ofgranular particles.

  11. Two- and Three-dimensional Transthoracic Echocardiographic Assessment of Tricuspid Valve Prolapse with Mid-to-Late Systolic Tricuspid Regurgitation.

    Science.gov (United States)

    Elsayed, Mahmoud; Thind, Munveer; Nanda, Navin C

    2015-06-01

    We present the two-dimensional echocardiographic findings of tricuspid valve prolapse with mid-to-late systolic tricuspid regurgitation and describe the incremental value provided by live/real time three-dimensional transthoracic echocardiography. We also discuss a potential pitfall when assessing the severity of regurgitation in this setting.

  12. A Proposed Maneuver to Guide Transseptal Puncture Using Real-Time Three-Dimensional Transesophageal Echocardiography: Pilot Study

    Directory of Open Access Journals (Sweden)

    Hani M. Mahmoud

    2015-01-01

    Full Text Available Aim of Study. To assess the feasibility of a new proposed maneuver “RATLe-90” using real-time three-dimensional transesophageal echocardiography (RT-3DTEE for anatomically oriented visualization of the interatrial septum (IAS in guiding the transseptal puncture TSP. Methods. The study included 20 patients (mean age, 60.2±6.7 years; 60% males who underwent TSP for different indications. RT-3DTEE was used to guide TSP. The proposed maneuver RATLe-90 (Rotate-Anticlockwise-Tilt-Left-90 was applied in all cases to have the anatomically oriented en face view of the IAS from the right atrial (RA aspect. Having this anatomically oriented view, we guided the TSP catheter towards the proper puncture site according to the planned procedure. Results. Using the RATLe-90 maneuver, the anatomically oriented en face view of the IAS from the RA was obtained in all patients. We were able to guide the puncture catheter to the proper puncture site on the IAS. The 3D images obtained were clearly understood by both echocardiographers and interventionists. The RATLe-90 maneuver acquisition time was 19.9±1.6 seconds. The time-to-tent was 64.8±16.3 seconds. Less TEE probe manipulations were needed while guiding the TSP. Conclusions. Application of RT3D-TEE during TSP using RATLe-90 maneuver is feasible with shorter fluoroscopy time and minimizing TEE probe manipulations.

  13. Evaluation of myocardial infarction size with three-dimensional speckle tracking echocardiography: a comparison with single photon emission computed tomography.

    Science.gov (United States)

    Wang, Qiushuang; Zhang, Chunhong; Huang, Dangsheng; Zhang, Liwei; Yang, Feifei; An, Xiuzhi; Ouyang, Qiaohong; Zhang, Meiqing; Wang, Shuhua; Guo, Jiarui; Ji, Dongdong

    2015-12-01

    To assess whether global and regional myocardial strains from three-dimensional speckle tracking echocardiography (3D-STE) correlate with myocardial infarction size (MIS) detected by single photon emission computed tomography (SPECT). Fifty-seven patients with a history of ST-segment elevation myocardial infarction (MI) within 3-6 months were enrolled, alongside 24 healthy volunteers. Left ventricular (LV) global area strain, global longitudinal strain (GLS), global radial strain, global circumferential strain, left ventricular ejection fraction (LVEF) and wall motion score index (WMSI) were measured and compared with the corresponding SPECT-detected MISs. Patients were sub-grouped into massive MIS group (MIS ≥ 12%) and small MIS group (MIS Myocardial strains of all the LV segments were compared with the corresponding MIS. Global myocardial strain parameters, LVEF and WMSI of the patients were significantly different from the control group (all P myocardial strain parameters were found between the massive and small MIS groups (all P myocardial strain parameters were observed between segments with and without transmural MIs (P myocardial strain parameters evaluated LV global MIS, 3D GLS had the highest diagnostic value. It also preliminarily gauged the degree of ischemia and necrosis of regional myocardial segments.

  14. The core helium flash revisited: II. Two and three-dimensional hydrodynamic simulations

    CERN Document Server

    Mocak, M; Weiss, A; Kifonidis, K

    2008-01-01

    We study turbulent convection during the core helium flash close to its peak by comparing the results of two and three-dimensional hydrodynamic simulations. We use a multidimensional Eulerian hydrodynamics code based on state-of-the-art numerical techniques to simulate the evolution of the helium core of a $1.25 M_{\\odot}$ Pop I star. Our three-dimensional hydrodynamic simulations of the evolution of a star during the peak of the core helium flash do not show any explosive behavior. The convective flow patterns developing in the three-dimensional models are structurally different from those of the corresponding two-dimensional models, and the typical convective velocities are smaller than those found in their two-dimensional counterparts. Three-dimensional models also tend to agree better with the predictions of mixing length theory. Our hydrodynamic simulations show the presence of turbulent entrainment that results in a growth of the convection zone on a dynamic time scale. Contrary to mixing length theory,...

  15. The core helium flash revisited. II. Two and three-dimensional hydrodynamic simulations

    Science.gov (United States)

    Mocák, M.; Müller, E.; Weiss, A.; Kifonidis, K.

    2009-07-01

    Context: We study turbulent convection during the core helium flash close to its peak by comparing the results of two and three-dimensional hydrodynamic simulations. Aims: In a previous study we found that the temporal evolution and the properties of the convection inferred from two-dimensional hydrodynamic studies are similar to those predicted by quasi-hydrostatic stellar evolutionary calculations. However, as vorticity is conserved in axisymmetric flows, two-dimensional simulations of convection are characterized by incorrect dominant spatial scales and exaggerated velocities. Here, we present three-dimensional simulations that eliminate the restrictions and flaws of two-dimensional models and that provide a geometrically unbiased insight into the hydrodynamics of the core helium flash. In particular, we study whether the assumptions and predictions of stellar evolutionary calculations based on the mixing-length theory can be confirmed by hydrodynamic simulations. Methods: We used a multidimensional Eulerian hydrodynamics code based on state-of-the-art numerical techniques to simulate the evolution of the helium core of a 1.25 M⊙ Pop I star. Results: Our three-dimensional hydrodynamic simulations of the evolution of a star during the peak of the core helium flash do not show any explosive behavior. The convective flow patterns developing in the three-dimensional models are structurally different from those of the corresponding two-dimensional models, and the typical convective velocities are lower than those found in their two-dimensional counterparts. Three-dimensional models also tend to agree more closely with the predictions of mixing length theory. Our hydrodynamic simulations show the turbulent entrainment that leads to a growth of the convection zone on a dynamic time scale. In contrast to mixing length theory, the outer part of the convection zone is characterized by a subadiabatic temperature gradient.

  16. A new boundary element formulation for two- and three-dimensional thermoelasticity using particular integrals

    Science.gov (United States)

    Henry, Donald P., Jr.; Banerjee, Prasanta K.

    1988-01-01

    New two- and three-dimensional BEM formulations are developed for steady-state and transient uncoupled thermoelasticity. These new procedures differ from previous work in that additional surface of volume integration is not required to incorporate thermal loads in the analysis. Instead, thermal body forces are introduced in the BEM system via particular integrals. The present formulation is implemented in a general-purpose multiregion system, and examples are presented to demonstrate the accuracy and versatility of the method.

  17. [Assessment right atrial function in patients with systemic lupus erythematosus by speckle tracking and three-dimensional echocardiography].

    Science.gov (United States)

    Ge, X Y; Shao, L; Zheng, Z L

    2016-12-20

    Objective: To evaluate right atrial function in systemic lupus erythematosus (SLE) with normal pulmonary pressure by using two dimensional-speckle tracking imaging (2D-STI) and real-time three-dimensional echocardiography(RT-3DE). Methods: A totoal of 40 patients with SLE and 40 control subjects were collected between December 2011 and May 2014 from Ningbo Medical Treatment Center Lihuili Hospital. Right atrial global longitudinal strain (RAGLS) and all kinds of right atrium volume index (RAVI) were detected. Relationship between tricuspid annular plane systolic excursion(TAPSE), tricuspid annulus systolic peak velocity (S'), right ventricular myocardial performance index (RVMPI), ETV/e'TV and the right atrium parameters were analyzed. Results: SLE group's right atrium maximal volume index(RAVImax)(33.5±11.1) ml/m(2,) right atrium minimal volume index (RAVImin)(13.2±4.5) ml/m(2,) right atrium presystolic volume index (RAVIpre) (2.57±10.2) ml/m(2,) right atrium total emptying volume index(RAVIt)(20.2±8.1)ml/m(2,) right atrium active emptying volume index (RAVIa)(12.5±7.5) ml/m(2)) were increased .But right atrium passive emptying volume index(RAVIp)( 7.8±2.7) ml/m(2) and right atrial global longitudinal strain (RAGLS) (38.2%±7.7% ) were decreased (both Pright atrial function by 2D-STI and RT-3DE could diagnose right atrial dysfunction in early stage of SLE patients with normal pulmonary pressure. The method is simple, has significant clinical value.

  18. Turbulent heat transport in two- and three-dimensional temperature fields

    Energy Technology Data Exchange (ETDEWEB)

    Samaraweera, Don Sarath Abesiri [Univ. of California, Berkeley, CA (United States)

    1978-03-01

    A fundamental numerical study of turbulent heat and mass transport processes in two- and three-dimensional convective flows is presented. The model of turbulence employed is the type referred to as a second-order closure. In this scheme transport equations for all nonzero components of the Reynolds stress tensor, for the isotropic dissipation rate of turbulent kinetic energy, for all nonzero scalar flux tensor components and for the mean square scalar fluctuations are solved by a finite difference method along with the mean momentum and mean enthalpy (or concentration) equations. The model used for the stresses was developed earlier. Parallel ideas were utilised in obtaining a model for turbulent heat and mass transfer processes. The study has focused especially on the problem of nonaxisymmetric convective heat and mass transport in pipes, which arises when the boundary conditions are not axisymmetric. The few available experimental data on such situations have indicated anisotropy in effective diffusivities. To expand the available data base an experiment was conducted to obtain heat transfer measurements in strong three-dimensional heating conditions. Numerical procedures especially suitable for incorporation of second-order turbulent closure models have been developed. The effect of circumferential conduction in the tube material, which is influential in the asymmetric heating data currently available, was accounted for directly by extending the finite difference calculations into the pipe wall. The principal goal of predicting three-dimensional scalar transfer has been achieved.

  19. Coexisting bicuspid aortic and pulmonary valves with normally related great vessels diagnosed by live/real time three-dimensional transesophageal echocardiography.

    Science.gov (United States)

    Kemaloğlu Öz, Tuğba; Karadeniz, Fatma Özpamuk; Gundlapalli, Hareesh; Erer, Betul; Sharma, Rohit K; Ahmed, Mustafa; Nanda, Navin C; Yıldırım, Aydın; Orhan, Gökçen; Öz, Ayhan; Eren, Mehmet

    2014-02-01

    Coexistence of bicuspid aortic and pulmonary valves in the same patient is a very rare entity identified mainly during surgery and postmortem. To the best of our knowledge, only one case has been diagnosed by two-dimensional echocardiography in a newborn with malposition of the great arteries but no images were presented. Here, we are reporting the first case of bicuspid pulmonary and aortic valves diagnosed by live/real time three-dimensional transesophageal echocardiography in an adult with normally related great arteries. © 2014, Wiley Periodicals, Inc.

  20. Kubo conductivity tensor for two- and three-dimensional magnetic nulls

    Science.gov (United States)

    St-Onge, D. A.; Sydora, R. D.

    2014-09-01

    The complete Kubo conductivity tensor is computed in two- and three-dimensional linear magnetic null systems using collisionless single-particle simulations. Regions of chaotic charged-particle dynamics are constructed for each case. It is found that stochastic frequency mixing of particle bounce motion, as well as gyromotion, contribute significantly to the conductivity. The conductivity curves are well approximated by power laws over a certain frequency range and the ac conductivity is found to be an order of magnitude smaller than the dc value, leading to enhanced resistivity, particularly near the cyclotron frequency. The ac conductivities must be accounted for in computation of the total dissipation.

  1. Energy thresholds for discrete breathers in one-, two- and three-dimensional lattices

    CERN Document Server

    Flach, S; MacKay, R S

    1997-01-01

    Discrete breathers are time-periodic, spatially localized solutions of equations of motion for classical degrees of freedom interacting on a lattice. They come in one-parameter families. We report on studies of energy properties of breather families in one-, two- and three-dimensional lattices. We show that breather energies have a positive lower bound if the lattice dimension of a given nonlinear lattice is greater than or equal to a certain critical value. These findings could be important for the experimental detection of discrete breathers.

  2. Correspondence Analysis in R, with Two- and Three-dimensional Graphics: The ca Package

    Directory of Open Access Journals (Sweden)

    Oleg Nenadic

    2007-02-01

    Full Text Available We describe an implementation of simple, multiple and joint correspondence analysis in R. The resulting package comprises two parts, one for simple correspondence analysis and one for multiple and joint correspondence analysis. Within each part, functions for computation, summaries and visualization in two and three dimensions are provided, including options to display supplementary points and perform subset analyses. Special emphasis has been put on the visualization functions that offer features such as different scaling options for biplots and three-dimensional maps using the rgl package. Graphical options include shading and sizing plot symbols for the points according to their contributions to the map and masses respectively.

  3. Two- and three-dimensional models for analysis of optical absorption in tungsten disulphide single crystals

    Indian Academy of Sciences (India)

    Dhairya A Dholakia; G K Solanki; S G Patel; M K Agarwal

    2001-06-01

    The optical energy gaps of WS2 single crystal were determined from the analysis of the absorption spectrum near the fundamental absorption edge at room temperature using light parallel to -axis incident normally on the basal plane. On the basis of two- and three-dimensional models it was found that both direct and indirect band transitions took place in WS2 and the indirect transition was of the allowed type. The optical energy gaps corresponding to both transitions were determined and the phonon energies associated with the indirect transitions estimated. The implications of the results have been discussed.

  4. Validation of admittance computed left ventricular volumes against real-time three-dimensional echocardiography in the porcine heart.

    Science.gov (United States)

    Kutty, Shelby; Kottam, Anil T; Padiyath, Asif; Bidasee, Keshore R; Li, Ling; Gao, Shunji; Wu, Juefei; Lof, John; Danford, David A; Kuehne, Titus

    2013-06-01

    The admittance and Wei's equation is a new technique for ventricular volumetry to determine pressure-volume relations that addresses traditional conductance-related issues of parallel conductance and field correction factor. These issues with conductance have prevented researchers from obtaining real-time absolute ventricular volumes. Moreover, the time-consuming steps involved in processing conductance catheter data warrant the need for a better catheter-based technique for ventricular volumetry. We aimed to compare the accuracy of left ventricular (LV) volumetry between the new admittance catheterization technique and transoesophageal real-time three-dimensional echocardiography (RT3DE) in a large-animal model. Eight anaesthetized pigs were used. A 7 French admittance catheter was positioned in the LV via the right carotid artery. The catheter was connected to an admittance control unit (ADVantage; Transonic Scisense Inc.), and data were recorded on a four-channel acquisition system (FA404; iWorx Systems). Admittance catheterization data and transoesophageal RT3DE (X7-2; Philips) data were simultaneously obtained with the animal ventilated, under neuromuscular blockade and monitored in baseline conditions and during dobutamine infusion. Left ventricular volumes measured from admittance catheterization (Labscribe; iWorx Systems) and RT3DE (Qlab; Philips) were compared. In a subset of four animals, admittance volumes were compared with those obtained from traditional conductance catheterization (MPVS Ultra; Millar Instruments). Of 37 sets of measurements compared, admittance- and RT3DE-derived LV volumes and ejection fractions at baseline and in the presence of dobutamine exhibited general agreement, with mean percentage intermethod differences of 10% for end-diastolic volumes, 14% for end-systolic volumes and 9% for ejection fraction; the respective intermethod differences between admittance and conductance in eight data sets compared were 11, 11 and 12

  5. New three-dimensional speckle-tracking echocardiography identifies global impairment of left ventricular mechanics with a high sensitivity in childhood cancer survivors.

    Science.gov (United States)

    Yu, Hong-kui; Yu, Wei; Cheuk, Daniel K L; Wong, Sophia J; Chan, Godfrey C F; Cheung, Yiu-fai

    2013-08-01

    The aim of this case-control study was to assess the usefulness of three-dimensional (3D) speckle-tracking echocardiography in the evaluation of global left ventricular (LV) myocardial performance in adolescent and adult survivors of childhood cancers. Fifty-three anthracycline-treated survivors of childhood cancers (mean age, 18.6 ± 5.1 years) and 38 controls were studied. Three-dimensional speckle-tracking echocardiography was performed to assess LV 3D global and segmental strain, time to peak segmental 3D strain, LV torsion, and ejection fraction. LV systolic dyssynchrony index (SDI) was calculated as the percentage of the standard deviation of times to peak strain of the 16 segments divided by the RR interval. A global performance index (GPI) was calculated as (global 3D strain × torsion)/SDI. The area under the receiver operating characteristic curve was calculated to determine the capability of various echocardiographic indices to discriminate between patients and controls. Compared with controls, patients had significantly reduced LV global 3D strain (P speckle-tracking echocardiography enables the derivation of an index of LV global performance that incorporates LV 3D strain, dyssynchrony, and torsion for the sensitive detection of altered LV mechanics in childhood cancer survivors. Copyright © 2013 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.

  6. The Proteus Navier-Stokes code. [two and three dimensional computational fluid dynamics

    Science.gov (United States)

    Towne, Charles E.; Schwab, John R.

    1992-01-01

    An effort is currently underway at NASA Lewis to develop two and three dimensional Navier-Stokes codes, called Proteus, for aerospace propulsion applications. Proteus solves the Reynolds-averaged, unsteady, compressible Navier-Stokes equations in strong conservation law form. Turbulence is modeled using a Baldwin-Lomax based algebraic eddy viscosity model. In addition, options are available to solve thin layer or Euler equations, and to eliminate the energy equation by assuming constant stagnation enthalpy. An extensive series of validation cases have been run, primarily using the two dimensional planar/axisymmetric version of the code. Several flows were computed that have exact solution such as: fully developed channel and pipe flow; Couette flow with and without pressure gradients; unsteady Couette flow formation; flow near a suddenly accelerated flat plate; flow between concentric rotating cylinders; and flow near a rotating disk. The two dimensional version of the Proteus code has been released, and the three dimensional code is scheduled for release in late 1991.

  7. Simplified single plane echocardiography is comparable to conventional biplane two-dimensional echocardiography in the evaluation of left atrial volume: a study validated by three-dimensional echocardiography in 143 individuals.

    Science.gov (United States)

    Vieira-Filho, Normando G; Mancuso, Frederico J N; Oliveira, Wercules A A; Gil, Manuel A; Fischer, Cláudio H; Moises, Valdir A; Campos, Orlando

    2014-03-01

    The left atrial volume index (LAVI) is a biomarker of diastolic dysfunction and a predictor of cardiovascular events. Three-dimensional echocardiography (3DE) is highly accurate for LAVI measurements but is not widely available. Furthermore, biplane two-dimensional echocardiography (B2DE) may occasionally not be feasible due to a suboptimal two-chamber apical view. Simplified single plane two-dimensional echocardiography (S2DE) could overcome these limitations. We aimed to compare the reliability of S2DE with other validated echocardiographic methods in the measurement of the LAVI. We examined 143 individuals (54 ± 13 years old; 112 with heart disease and 31 healthy volunteers; all with sinus rhythm, with a wide range of LAVI). The results for all the individuals were compared with B2DE-derived LAVIs and validated using 3DE. The LAVIs, as determined using S2DE (32.7 ± 13.1 mL/m(2)), B2DE (31.9 ± 12.7 mL/m(2)), and 3DE (33.1 ± 13.4 mL/m(2)), were not significantly different from each other (P = 0.85). The S2DE-derived LAVIs correlated significantly with those obtained using both B2DE (r = 0.98; P < 0.001) and 3DE (r = 0.93; P < 0.001). The mean difference between the S2DE and B2DE measurements was <1.0 mL/m(2). Using the American Society of Echocardiography criteria for grading LAVI enlargement (normal, mild, moderate, severe), we observed an excellent agreement between the S2DE- and B2DE-derived classifications (κ = 0.89; P < 0.001). S2DE is a simple, rapid, and reliable method for LAVI measurement that may expand the use of this important biomarker in routine echocardiographic practice.

  8. Two- and three-dimensional marginal separation of laminar, incompressible viscous jets

    Energy Technology Data Exchange (ETDEWEB)

    Braun, S.; Kluwick, A. [TU Vienna (Austria). Inst. of Fluid Dynamics and Heat Transfer

    2000-07-01

    If a laminar two-dimensional viscous jet flows past a wall which is curved up an adverse pressure gradient forms inside the jet owing to the streamline curvature. As a consequence, solutions based on the boundary layer approximation may terminate in the form of a Goldstein-singularity or may develop a marginal separation singularity. The latter one is characterized by the fact that the wall shear stress vanishes in a single point but immediately recovers and can be used to develop a local interaction strategy which is able to describe small separation regions. In the present study the results obtained by Zametaev for locally plane walls are extended to include the effects of two- and three-dimensional obstacles. Special emphasis is placed on the nonuniqueness of the solution for the wall shear stress distribution which is governed by a nonlinear integro-differential equation. (orig.)

  9. A review of the responses of two- and three-dimensional engineered tissues to electric fields.

    Science.gov (United States)

    Hronik-Tupaj, Marie; Kaplan, David L

    2012-06-01

    The application of external biophysical signals is one approach to tissue engineering that is explored less often than more traditional additions of exogenous biochemical and chemical factors to direct cell and tissue outcomes. The study of bioelectromagnetism and the field of electrotherapeutics have evolved over the years, and we review biocompatible electric stimulation devices and their successful application to tissue growth. Specifically, information on capacitively coupled alternating current, inductively coupled alternating current, and direct current devices is described. Cell and tissue responses from the application of these devices, including two- and three-dimensional in vitro studies and in vivo studies, are reviewed with regard to cell proliferation, adhesion, differentiation, morphology, and migration and tissue function. The current understanding of cellular mechanisms related to electric stimulation is detailed. The advantages of electric stimulation are compared with those pf other techniques, and areas in which electric fields are used as an adjuvant therapy for healing and regeneration are discussed.

  10. Microstructure in two- and three-dimensional hybrid simulations of perpendicular collisionless shocks

    CERN Document Server

    Burgess, David; Gingell, Peter W; Trávníček, Pavel M

    2016-01-01

    Supercritical collisionless perpendicular shocks have an average macrostructure determined primarily by the dynamics of ions specularly reflected at the magnetic ramp. Within the overall macrostructure, instabilities, both linear and nonlinear, generate fluctuations and microstructure. To identify the sources of such microstructure, high-resolution two- and three-dimensional simulations have been carried out using the hybrid method, wherein the ions are treated as particles and the electron response is modelled as a massless fluid. We confirm the results of earlier 2-D simulations showing both field-parallel aligned propagating fluctuations and fluctuations carried by the reflected-gyrating ions. In addition, it is shown that, for 2-D simulations of the shock coplanarity plane, the presence of short-wavelength fluctuations in all magnetic components is associated with the ion Weibel instability driven at the upstream edge of the foot by the reflected-gyrating ions. In 3-D simulations we show for the first tim...

  11. A Review of the Responses of Two- and Three-Dimensional Engineered Tissues to Electric Fields

    Science.gov (United States)

    Hronik-Tupaj, Marie

    2012-01-01

    The application of external biophysical signals is one approach to tissue engineering that is explored less often than more traditional additions of exogenous biochemical and chemical factors to direct cell and tissue outcomes. The study of bioelectromagnetism and the field of electrotherapeutics have evolved over the years, and we review biocompatible electric stimulation devices and their successful application to tissue growth. Specifically, information on capacitively coupled alternating current, inductively coupled alternating current, and direct current devices is described. Cell and tissue responses from the application of these devices, including two- and three-dimensional in vitro studies and in vivo studies, are reviewed with regard to cell proliferation, adhesion, differentiation, morphology, and migration and tissue function. The current understanding of cellular mechanisms related to electric stimulation is detailed. The advantages of electric stimulation are compared with those pf other techniques, and areas in which electric fields are used as an adjuvant therapy for healing and regeneration are discussed. PMID:22046979

  12. Three-dimensional echocardiography with tissue harmonic imaging shows excellent reproducibility in assessment of left ventricular volumes

    DEFF Research Database (Denmark)

    Kim, Won Yong; Søgaard, Peter; Egeblad, Henrik;

    2001-01-01

    We studied the reproducibility of repeated measurements of left ventricular (LV) volumes by 2-dimensional (biplane method of disks) and 3-dimensional echocardiography (coaxial scanning) with tissue harmonic imaging. Ten healthy subjects underwent estimation of LV volumes by transthoracic echocard......We studied the reproducibility of repeated measurements of left ventricular (LV) volumes by 2-dimensional (biplane method of disks) and 3-dimensional echocardiography (coaxial scanning) with tissue harmonic imaging. Ten healthy subjects underwent estimation of LV volumes by transthoracic...

  13. Three-dimensional propagation imaging of left ventricular activation by speckle-tracking echocardiography to predict responses to cardiac resynchronization therapy.

    Science.gov (United States)

    Seo, Yoshihiro; Ishizu, Tomoko; Kawamura, Ryo; Yamamoto, Masayoshi; Kuroki, Kenji; Igarashi, Miyako; Sekiguchi, Yukio; Nogami, Akihiko; Aonuma, Kazutaka

    2015-05-01

    On the basis of the electromechanical coupling theory, an activation imaging system has been developed with three-dimensional speckle-tracking echocardiography. The aim of this study was to determine the association between left ventricular (LV) propagation patterns by activation imaging and response to cardiac resynchronization therapy (CRT). This was a retrospective, single-center study. Eighty-one patients undergoing CRT, of whom 50 (61.7%) had left bundle branch block (LBBB), were enrolled. Activation imaging studies were performed with a three-dimensional speckle-tracking echocardiographic system, which allowed visualization of LV activation propagation and measurement of the time from the QRS complex to activation onset. A CRT volume responder was defined as a patient with ≥15% reduction of LV end-systolic volume at 6 months after CRT. Clinical outcomes were assessed with the composite end point of death due to cardiac causes or unplanned hospitalization for cardiac diseases. In patients with LBBB, the main activation pattern (74%) was a U-shaped propagation pattern, which was characterized as propagation from the midseptum to the lateral or posterior wall through the apex. In patients without LBBB, various non-U-shaped propagation patterns were observed in the majority of patients (97%). Among the 41 CRT responders, almost all (87.8%) had the U-shaped propagation pattern. During follow-up (median, 20 months), 29 patients (35.8%) reached the clinical end points. In a multivariate Cox proportional hazards model, a U-shaped propagation pattern was associated with the end points independently of LBBB or LV end-diastolic volume. The U-shaped propagation pattern on three-dimensional speckle-tracking echocardiography was significantly associated with a favorable CRT response. Activation pattern analysis may provide additional information to predict response to CRT. Copyright © 2015 American Society of Echocardiography. Published by Elsevier Inc. All rights

  14. Evaluation value of real-time three-dimensional adenosine stress echocardiography and coronary angiography for patients with stable angina pectoris

    Institute of Scientific and Technical Information of China (English)

    Ya-Li Wu; Nan-Jue Jiang; Yan Cai

    2016-01-01

    Objective:To study the evaluation value of real-time three-dimensional adenosine stress echocardiography and coronary angiography for patients with stable angina pectoris. Methods:A total of 45 patients diagnosed with stable angina pectoris in our hospital between May 2014 and December 2015 were selected as the stable angina pectoris group (SAP group) of the study and 50 healthy subjects receiving physical examination in our hospital during the same period were selected as control group. Real-time three-dimensional adenosine stress echocardiography was performed to measure coronary flow reserve (CFR), serum was collected to determine lipid metabolism indexes and inflammation indexes, and peripheral blood mononuclear cells were collected to determine the expression levels of inflammatory regulatory molecules.Results:CFR of SAP group was significantly lower than that of control group and the more the number of coronary lesions, the lower the CFR of SAP group; serum Lp(a), LDL-C, ApoB, MIF-1α, ICAM-1, VCAM-1, CD40 and CD40L content as well as the fluorescence intensity of peripheral blood mononuclear cell surface TLR4 and NF-κB of SAP group were significantly higher than those of control group and negatively correlated with CFR level while serum HDL-C and ApoA1 content as well as the fluorescence intensity of peripheral blood mononuclear cell surface TIPE2 and BACH2 were significantly lower than those of control group and positively correlated with CFR level.Conclusion:CFR measured by real-time three-dimensional adenosine stress echocardiography significantly reduces in patients with stable angina pectoris and is correlated with lipid metabolism state and the degree of inflammation.

  15. Assessment value of real-time three-dimensional echocardiography on right ventricular systolic function in patients with tetralogy of Fallot

    Institute of Scientific and Technical Information of China (English)

    Jin-Hua Su; Hai-Yan Kou; Li Liang

    2016-01-01

    Objective:To analyze the assessment value of real-time three-dimensional echocardiography on right ventricular systolic function in patients with tetralogy of Fallot (TOF).Methods:63 cases of children with tetralogy of Fallot undergoing surgical treatment in our hospital from September 2011 to September 2014 were chosen as observation group, 72 cases of normal children receiving health examination in our hospital during the same period were chosen as normal control group, all of them received two-dimensional and three-dimensional ultrasound examination, and right ventricular systolic function of TOF children was compared and observed.Results:1) TOF patients’ preoperative left pulmonary artery inner diameter was 5.38–9.65 mm, right pulmonary artery inner diameter was 5.34–9.15 mm, average pulmonary artery index (Nakata index) was (160.92±21.58) mm2/m2; 2) TOF patients’ preoperative RVEDV and RVESV values were greater than those of normal control group and RVEF value was less than that of normal control group (P<0.05); RVEDV and RVESV 6 months after surgery increased, RVEF decreased, and compared with before surgery, there was significant difference (P<0.05); 3) TOF patients’ preoperative three-dimensional ultrasound RVESV and RVEDV values were higher than results of two-dimensional ultrasound examination (P<0.05); 4) TOF patients’ preoperative RVEF had significant positive correlation with Nakata index, r=0.653 (P<0.05).Conclusions: Real-time three-dimensional echocardiography can accurately and objectively assess right ventricular systolic function in patients with Tetralogy of Fallot, and contributes to the assessment of treatment effect and long-term prognosis.

  16. Incremental value of live/real time three-dimensional transesophageal echocardiography over the two-dimensional technique in the assessment of aortic atherosclerotic thrombi and ulcers.

    Science.gov (United States)

    Elsayed, Mahmoud; Bulur, Serkan; Kalla, Aditi; Ahmed, Mustafa I; Hsiung, Ming C; Uygur, Begum; Alagic, Nermina; Sungur, Aylin; Singh, Satinder; Nanda, Navin C

    2016-08-01

    We present two cases in whom live/real time three-dimensional transesophageal echocardiography (3DTEE) provided incremental value in the assessment of atherosclerotic disease in the aorta. In one patient, it identified additional atherosclerotic ulcers as well as thrombi within them which were missed by two-dimensional (2D) TEE. In both cases, the size of the large mobile atherosclerotic plaque was underestimated by 2DTEE as compared with 3DTEE. Furthermore, 3DTEE provided volume quantification of the thrombi and ulcers which is not possible by 2DTEE. The echocardiographic findings of atherosclerotic plaques were confirmed by computed tomography in one patient and by surgery in the other.

  17. Comparison of contrast enhanced three dimensional echocardiography with MIBI gated SPECT for the evaluation of left ventricular function

    Directory of Open Access Journals (Sweden)

    Cosyns Bernard

    2009-06-01

    Full Text Available Abstract Background In clinical practice and in clinical trials, echocardiography and scintigraphy are used the most for the evaluation of global left ejection fraction (LVEF and left ventricular (LV volumes. Actually, poor quality imaging and geometrical assumptions are the main limitations of LVEF measured by echocardiography. Contrast agents and 3D echocardiography are new methods that may alleviate these potential limitations. Methods Therefore we sought to examine the accuracy of contrast 3D echocardiography for the evaluation of LV volumes and LVEF relative to MIBI gated SPECT as an independent reference. In 43 patients addressed for chest pain, contrast 3D echocardiography (RT3DE and MIBI gated SPECT were prospectively performed on the same day. The accuracy and the variability of LV volumes and LVEF measurements were evaluated. Results Due to good endocardial delineation, LV volumes and LVEF measurements by contrast RT3DE were feasible in 99% of the patients. The mean LV end-diastolic volume (LVEDV of the group by scintigraphy was 143 ± 65 mL and was underestimated by triplane contrast RT3DE (128 ± 60 mL; p Conclusion Contrast RT3DE allows an accurate assessment of LVEF compared to the LVEF measured by SPECT, and shows low variability between observers. Although RT3DE triplane provides accurate evaluation of left ventricular function, RT3DE full-volume is superior to triplane modality in patients with suspected coronary artery disease.

  18. Comparison of two- and three-dimensional simulations of miscible Rayleigh-Taylor instability

    Energy Technology Data Exchange (ETDEWEB)

    Cabot, W

    2006-02-23

    A comparison of two-dimensional and three-dimensional high-resolution numerical large-eddy simulations of planar, miscible Rayleigh-Taylor instability flows are presented. The resolution of the three-dimensional simulation is sufficient to attain a fully turbulent state. A number of different statistics from the mixing region (e.g., growth rates, PDFs, mixedness measures, and spectra) are used to demonstrate that two-dimensional flow simulations differ substantially from the three-dimensional one. It is found that the two-dimensional flow grows more quickly than its three-dimensional counterpart at late times, develops larger structures, and is much less well mixed. These findings are consistent with the concept of inverse cascade in two-dimensional flow, as well as the influence of a reduced effective Atwood number on miscible flow.

  19. Deformation imaging and three-dimensional echocardiography : implications on clinical management of patients with ischemic heart disease

    NARCIS (Netherlands)

    Hoogslag, Georgette Elise

    2016-01-01

    Evaluation of patients with ischemic heart disease using echocardiography is indispensable. Both in the acute setting of STEMI, at follow-up and in the chronic phase during the possible development of heart failure, routine echocardiographic assessment is an essential part of daily clinical

  20. Dissipation via Landau Damping in Two- and Three-Dimensional Plasma Turbulence

    CERN Document Server

    Li, Tak Chu; Klein, Kristopher G; TenBarge, Jason M

    2015-01-01

    Plasma turbulence is ubiquitous in space and astrophysical plasmas, playing an important role in plasma energization, but the physical mechanisms that lead to dissipation of the turbulent energy remain to be definitively identified. This work addresses the fundamental physics of turbulent dissipation by examining the velocity-space structure that develops as a result of the collisionless interaction between the turbulent electromagnetic fluctuations and the particles in a low beta plasma. Both two- and three-dimensional (2D and 3D) nonlinear gyrokinetic simulations show an electron velocity-space signature qualitatively similar to that of the linear Landau damping of Alfv\\'en waves in a 3D linear simulation. This evidence strongly suggests that the turbulent energy is transferred by Landau damping to electrons in low beta plasmas in both 2D and 3D, making possible the ultimate irreversible heating of the plasma. Although, in the 2D case with no variation along the equilibrium magnetic field, it may be expecte...

  1. Dynamic Analysis of Pig through Two and Three Dimensional Gas Pipeline

    Directory of Open Access Journals (Sweden)

    Malihe Mirshamsi

    2015-01-01

    Full Text Available This paper deals with the dynamic analysis and simulation of Pipeline Inspection Gage (PIG through the two and three dimensional gas pipelines. Continuity, momentum and the state equations are employed to achieve the gas flow parameters like density, velocity and pressure along the pipeline since the dynamic behavior of the pig depends on the flow field characteristics. Also, a differential equation which governs the dynamic behavior of the pig is derived. The pig is assumed to be a small rigid body with a bypass hole in its body. The variation of the diameter of the bypass port, which is controlled by a valve, is considered in this research. The path of the pig or geometry of the pipeline is assumed to be 2D and 3D curve. 2D and 3D simulations of the pig motion are performed individually using Rung- Kutta method and a case has been solved and discussed for each of them. The simulation results show that the derived equations are valid and effective for online estimating of the position, velocity and forces acting on the pig in gas pipelines at any time of the motion.

  2. Microstructure in two- and three-dimensional hybrid simulations of perpendicular collisionless shocks

    Science.gov (United States)

    Burgess, David; Hellinger, Petr; Gingell, Imogen; Trávníček, Pavel M.

    2016-08-01

    Supercritical collisionless perpendicular shocks have an average macrostructure determined primarily by the dynamics of ions specularly reflected at the magnetic ramp. Within the overall macrostructure, instabilities, both linear and nonlinear, generate fluctuations and microstructure. To identify the sources of such microstructure, high-resolution two- and three-dimensional simulations have been carried out using the hybrid method, wherein the ions are treated as particles and the electron response is modelled as a massless fluid. We confirm the results of earlier two-dimensional (2-D) simulations showing both field-parallel aligned propagating fluctuations and fluctuations carried by the reflected-gyrating ions. In addition, it is shown that, for 2-D simulations of the shock coplanarity plane, the presence of short-wavelength fluctuations in all magnetic components is associated with the ion Weibel instability driven at the upstream edge of the foot by the reflected-gyrating ions. In 3-D simulations we show for the first time that the dominant microstructure is due to a coupling between field-parallel propagating fluctuations in the ramp and the motion of the reflected ions. This results in a pattern of fluctuations counter-propagating across the surface of the shock at an angle inclined to the magnetic field direction, due to a combination of field-parallel motion at the Alfvén speed of the ramp and motion in the sense of gyration of the reflected ions.

  3. A statistical conservation law in two and three dimensional turbulent flows

    CERN Document Server

    Frishman, Anna; De Lillo, Filippo; Liberzon, Alex

    2015-01-01

    Particles in turbulence live complicated lives. It is nonetheless sometimes possible to find order in this complexity. It was proposed in [Falkovich et al., Phys. Rev. Lett. 110, 214502 (2013)] that pairs of Lagrangian tracers at small scales, in an incompressible isotropic turbulent flow, have a statistical conservation law. More specifically, in a d-dimensional flow the distance $R(t)$ between two neutrally buoyant particles, raised to the power $-d$ and averaged over velocity realizations, remains at all times equal to the initial, fixed, separation raised to the same power. In this work we present evidence from direct numerical simulations of two and three dimensional turbulence for this conservation. In both cases the conservation is lost when particles exit the linear flow regime. In 2D we show that, as an extension of the conservation law, a Evans-Cohen-Morriss/Gallavotti-Cohen type fluctuation relation exists. We also analyse data from a 3D laboratory experiment [Liberzon et al., Physica D 241, 208 (2...

  4. Additional value of three-dimensional transesophageal echocardiography for patients with mitral valve stenosis undergoing balloon valvuloplasty.

    Science.gov (United States)

    Langerveld, Jorina; Valocik, Gabriel; Plokker, H W Thijs; Ernst, Sjef M P G; Mannaerts, Herman F J; Kelder, Johannes C; Kamp, Otto; Jaarsma, Wybren

    2003-08-01

    The objective of this study was to validate the additional value of 3-dimensional (3D) transesophageal echocardiography (TEE) for patients with mitral valve stenosis undergoing percutaneous mitral balloon valvotomy (PTMV). Therefore, in a series of 21 patients with severe mitral valve stenosis selected for PTMV, 3D TEE was performed before and after PTMV. The mitral valve area was assessed by planimetry pre- and post-PTMV; the mitral valve volume was assessed and attention was paid to the amount of fusion of the commissures. These results were compared with findings by 2-dimensional transthoracic echocardiography using pressure half-time method for assessment of mitral valve area, and were analyzed for the prediction of successful outcome. Pre-PTMV the mitral valve area assessed by 3D TEE was 1.0 +/- 0.3 cm(2) vs 1.2 +/- 0.4 cm(2) assessed by 2-dimensional transthoracic echocardiography (P =.03) and post-PTMV it was 1.8 +/- 0.5 cm(2) vs 1.9 +/- 0.6 cm(2) (not significant), respectively. The mitral valve volume could be assessed by 3D TEE (mean 2.4 +/- 2.5 cm(3)) and was inversely correlated to a successful PTMV procedure (P <.001). The 3D TEE method enabled a better description of the mitral valvular anatomy, especially post-PTMV. We conclude that 3D TEE will have additional value over 2-dimensional echocardiography in this group of patients, for selection of patients pre-PTMV, and for analyzing pathology of the mitral valve afterward.

  5. Real-Time Three-Dimensional Echocardiography: Characterization of Cardiac Anatomy and Function—Current Clinical Applications and Literature Review Update

    Science.gov (United States)

    Velasco, Omar; Beckett, Morgan Q.; James, Aaron W.; Loehr, Megan N.; Lewis, Taylor G.; Hassan, Tahmin; Janardhanan, Rajesh

    2017-01-01

    Abstract Our review of real-time three-dimensional echocardiography (RT3DE) discusses the diagnostic utility of RT3DE and provides a comparison with two-dimensional echocardiography (2DE) in clinical cardiology. A Pubmed literature search on RT3DE was performed using the following key words: transthoracic, two-dimensional, three-dimensional, real-time, and left ventricular (LV) function. Articles included perspective clinical studies and meta-analyses in the English language, and focused on the role of RT3DE in human subjects. Application of RT3DE includes analysis of the pericardium, right ventricular (RV) and LV cavities, wall motion, valvular disease, great vessels, congenital anomalies, and traumatic injury, such as myocardial contusion. RT3DE, through a transthoracic echocardiography (TTE), allows for increasingly accurate volume and valve motion assessment, estimated LV ejection fraction, and volume measurements. Chamber motion and LV mass approximation have been more accurately evaluated by RT3DE by improved inclusion of the third dimension and quantification of volumetric movement. Moreover, RT3DE was shown to have no statistical significance when comparing the ejection fractions of RT3DE to cardiac magnetic resonance (CMR). Analysis of RT3DE data sets of the LV endocardial exterior allows for the volume to be directly quantified for specific phases of the cardiac cycle, ranging from end systole to end diastole, eliminating error from wall motion abnormalities and asymmetrical left ventricles. RT3DE through TTE measures cardiac function with superior diagnostic accuracy in predicting LV mass, systolic function, along with LV and RV volume when compared with 2DE with comparable results to CMR.

  6. Energy Dissipation and Landau Damping in Two- and Three-dimensional Plasma Turbulence

    Science.gov (United States)

    Li, Tak Chu; Howes, Gregory G.; Klein, Kristopher G.; TenBarge, Jason M.

    2016-12-01

    Plasma turbulence is ubiquitous in space and astrophysical plasmas, playing an important role in plasma energization, but the physical mechanisms leading to dissipation of the turbulent energy remain to be definitively identified. Kinetic simulations in two dimensions (2D) have been extensively used to study the dissipation process. How the limitation to 2D affects energy dissipation remains unclear. This work provides a model of comparison between two- and three-dimensional (3D) plasma turbulence using gyrokinetic simulations; it also explores the dynamics of distribution functions during the dissipation process. It is found that both 2D and 3D nonlinear gyrokinetic simulations of a low-beta plasma generate electron velocity-space structures with the same characteristics as that of the linear Landau damping of Alfvén waves in a 3D linear simulation. The continual occurrence of the velocity-space structures throughout the turbulence simulations suggests that the action of Landau damping may be responsible for the turbulent energy transfer to electrons in both 2D and 3D, and makes possible the subsequent irreversible heating of the plasma through collisional smoothing of the velocity-space fluctuations. Although, in the 2D case where variation along the equilibrium magnetic field is absent, it may be expected that Landau damping is not possible, a common trigonometric factor appears in the 2D resonant denominator, leaving the resonance condition unchanged from the 3D case. The evolution of the 2D and 3D cases is qualitatively similar. However, quantitatively, the nonlinear energy cascade and subsequent dissipation is significantly slower in the 2D case.

  7. Statistical conservation law in two- and three-dimensional turbulent flows

    Science.gov (United States)

    Frishman, Anna; Boffetta, Guido; De Lillo, Filippo; Liberzon, Alex

    2015-03-01

    Particles in turbulence live complicated lives. It is nonetheless sometimes possible to find order in this complexity. It was proposed in Falkovich et al. [Phys. Rev. Lett. 110, 214502 (2013), 10.1103/PhysRevLett.110.214502] that pairs of Lagrangian tracers at small scales, in an incompressible isotropic turbulent flow, have a statistical conservation law. More specifically, in a d -dimensional flow the distance R (t ) between two neutrally buoyant particles, raised to the power -d and averaged over velocity realizations, remains at all times equal to the initial, fixed, separation raised to the same power. In this work we present evidence from direct numerical simulations of two- and three-dimensional turbulence for this conservation. In both cases the conservation is lost when particles exit the linear flow regime. In two dimensions we show that, as an extension of the conservation law, an Evans-Cohen-Morriss or Gallavotti-Cohen type fluctuation relation exists. We also analyze data from a 3D laboratory experiment [Liberzon et al., Physica D 241, 208 (2012), 10.1016/j.physd.2011.07.008], finding that although it probes small scales they are not in the smooth regime. Thus instead of , we look for a similar, power-law-in-separation conservation law. We show that the existence of an initially slowly varying function of this form can be predicted but that it does not turn into a conservation law. We suggest that the conservation of , demonstrated here, can be used as a check of isotropy, incompressibility, and flow dimensionality in numerical and laboratory experiments that focus on small scales.

  8. Comparison of inverse dynamics calculated by two- and three-dimensional models during walking

    DEFF Research Database (Denmark)

    Alkjaer, T; Simonsen, E B; Dyhre-Poulsen, P

    2001-01-01

    The purpose of the study was to compare joint moments calculated by a two- (2D) and a three-dimensional (3D) inverse dynamics model to examine how the different approaches influenced the joint moment profiles. Fifteen healthy male subjects participated in the study. A five-camera video system rec...

  9. Evaluation of left ventricular rotation by two-dimensional speckle tracking method and real-time three-dimensional echocardiography: comparison with MRI tagging method.

    Science.gov (United States)

    Hayashi, Hidetaka; Izumi, Chisato; Takahashi, Shuichi; Uchikoshi, Masato; Yamazaki, Ryou; Asanuma, Toshihiko; Ishikura, Fuminobu; Beppu, Shintaro; Nakatani, Satoshi

    2011-09-01

    Recently, it has become possible to evaluate left ventricular (LV) torsion by two-dimensional (2D) speckle tracking images. However, LV torsion is a three-dimensional (3D) performance, which per se cannot be assessed by the 2D speckle tracking method. The present study investigated the accuracy of the 2D speckle tracking method and real-time 3D echocardiography in measuring LV rotation, comparing with the MRI tagging method. We assessed LV apical rotation using the 2D speckle tracking method, real-time 3D echocardiography, and MRI tagging method in 26 normal subjects, and compared the results of these three methods. LV apical rotation was measured just before the level in which the posterior papillary muscle was absorbed into the free wall. The degree of LV apical rotation evaluated by the 2D speckle tracking method (Δθ 2D) was significantly smaller than that evaluated by 3D echocardiography (Δθ 3D) and the MRI tagging method (Δθ MRI) (Δθ 2D 7.3 ± 2.8°; Δθ 3D 8.8 ± 3.4°; Δθ MRI 9.0 ± 3.4°; Δθ 2D vs. Δθ 3D, p = 0.0001; Δθ 2D vs. Δθ MRI, p speckle tracking method compared with the MRI tagging method, whereas it could be precisely measured by 3D echocardiography.

  10. Comparison of Two- and Three-dimensional Ultrasonography in the Evaluation of Lesion Level in Fetuses with Spina Bifida.

    Science.gov (United States)

    Requeijo, Márcio José Rosa; Bunduki, Victor; Francisco, Rossana Pulcineli Vieira; Lopes, Marco Antonio Borges; Ruano, Rodrigo; Zugaib, Marcelo

    2016-03-01

    To evaluate the precision of both two- and three-dimensional ultrasonography in determining vertebral lesion level (the first open vertebra) in patients with spina bifida. This was a prospective longitudinal study comprising of fetuses with open spina bifida who were treated in the fetal medicine division of the department of obstetrics of Hospital das Clínicas of the Universidade de São Paulo between 2004 and 2013. Vertebral lesion level was established by using both two- and three-dimensional ultrasonography in 50 fetuses (two examiners in each method). The lesion level in the neonatal period was established by radiological assessment of the spine. All pregnancies were followed in our hospital prenatally, and delivery was scheduled to allow immediate postnatal surgical correction. Two-dimensional sonography precisely estimated the spina bifida level in 53% of the cases. The estimate error was within one vertebra in 80% of the cases, in up to two vertebrae in 89%, and in up to three vertebrae in 100%, showing a good interobserver agreement. Three-dimensional ultrasonography precisely estimated the lesion level in 50% of the cases. The estimate error was within one vertebra in 82% of the cases, in up to two vertebrae in 90%, and in up to three vertebrae in 100%, also showing good interobserver agreement. Whenever an estimate error was observed, both two- and three-dimensional ultrasonography scans tended to underestimate the true lesion level (55.3% and 62% of the cases, respectively). No relevant difference in diagnostic performance was observed between the two- and three-dimensional ultrasonography. The use of three-dimensional ultrasonography showed no additional benefit in diagnosing the lesion level in the fetuses with spina bifida. Errors in both methods showed a tendency to underestimate lesion level. Thieme Publicações Ltda Rio de Janeiro, Brazil.

  11. Prenatal diagnosis of Beckwith-Wiedemann syndrome by two- and three-dimensional ultrasonography

    Directory of Open Access Journals (Sweden)

    Edward Araujo Junior

    2013-12-01

    Full Text Available Beckwith-Wiedemann syndrome is a genetic syndrome characterized by macroglossia, omphalocele, fetal gigantism and neonatal hypoglycemia. The authors report a case of Beckwith-Wiedemann syndrome diagnosed in a 32-year-old primigravida in whom two-dimensional ultrasonography revealed the presence of abdominal wall cyst, macroglossia and polycystic kidneys. Three-dimensional ultrasonography in rendering mode was of great importance to confirm the previous two-dimensional ultrasonography findings.

  12. Critical exponents, hyperscaling and universal amplitude ratios for two- and three-dimensional self-avoiding walks

    CERN Document Server

    Li, B; Sokal, A D; Li, Bin; Madras, Neal; Sokal, Alan D

    1994-01-01

    We make a high-precision Monte Carlo study of two- and three-dimensional self-avoiding walks (SAWs) of length up to 80000 steps, using the pivot algorithm and the Karp-Luby algorithm. We study the critical exponents \

  13. New cases of integrable systems with dissipation on tangent bundles of two- and three-dimensional spheres

    Science.gov (United States)

    Shamolin, M. V.

    2016-12-01

    Integrability in elementary functions is demonstrated for some classes of dynamic systems on tangent bundles of two- and three-dimensional spheres. The force fields possess the so-called variable dissipation with a zero mean and generalize those considered earlier.

  14. Comprehensive assessment of biventricular function and aortic stiffness in athletes with different forms of training by three-dimensional echocardiography and strain imaging.

    Science.gov (United States)

    Vitarelli, Antonio; Capotosto, Lidia; Placanica, Giuseppe; Caranci, Fiorella; Pergolini, Mario; Zardo, Francesco; Martino, Francesco; De Chiara, Stefania; Vitarelli, Massimo

    2013-10-01

    Previous studies have shown distinct models of cardiac adaptations to the training in master athletes and different effects of endurance and strength-training on cardiovascular function. We attempted to assess left-ventricular (LV) function, aortic (Ao) function, and right-ventricular (RV) function in athletes with different forms of training by using three-dimensional (3D) echocardiography, tissue Doppler imaging (TDI) and speckle-tracking imaging (STI). We examined 35 male marathon runners (endurance-trained athletes, ETA), 35 powerlifting athletes (strength-trained athletes, STA), 35 martial arts athletes (mixed-trained athletes, MTA), and 35 sedentary untrained healthy men (controls, CTR). Two-dimensional and three-dimensional echocardiography were performed for the assessment of LV and RV systolic/diastolic function. LV and RV longitudinal strain (LS) and LV torsion (LVtor) were determined using STI (EchoPAC BT11, GE-Ultrasound). Maximum velocity of systolic wall expansion peaks (AoSvel) was determined using TDI. ETA experienced LV eccentric hypertrophy with increased 3D LV end-diastolic volume and mass and significant increase in peak systolic apical rotation and LVtor. In all groups of athletes, RV-LS was reduced at rest and improved after exercise. AoSvel was significantly increased in ETA and MTA and significantly decreased in STA compared with CTR. There were good correlations between LV remodelling and aortic stiffness values. Multivariate analysis showed aortic wall velocities to be independently related to LV mass index. In strength-trained, endurance-trained, and mixed-trained athletes, ventricular and vascular response assessed by 3DE, TDI, and STI underlies different adaptations of LV, RV, and aortic indexes.

  15. Roles of real-time three-dimensional transesophageal echocardiography in peri-operation of transcatheter left atrial appendage closure

    Science.gov (United States)

    Zhou, Qing; Song, Hongning; Zhang, Lan; Deng, Qing; Chen, Jinling; Hu, Bo; Wang, Yijia; Guo, Ruiqiang

    2017-01-01

    Abstract Left atrial appendage (LAA) closure is a new treatment option for the prevention of stroke in patients with nonvalvular atrial fibrillation (AF). Conventional 2-dimensional transesophageal echocardiography (2D TEE) has some limitations in the imaging assessment of LAA closure. Real-time 3-dimensional transesophageal echocardiography (RT-3D TEE) allows for detailed morphologic assessment of the LAA. In this study, we aim to determine the clinical values of RT-3D TEE in the periprocedure of LAA closure. Thirty-eight persistent or paroxysmal AF patients with indications for LAA closure were enrolled in this study. RT-3D TEE full volume data of the LAA were recorded before operation to evaluate the anatomic feature, the landing zone dimension, and the depth of the LAA. On this basis, selection of LAA closure device was carried out. During the procedure, RT-3D TEE was applied to guide the interatrial septal puncture, device operation, and evaluate the occlusion effects. The patients were follow-up 1 month and 3 months postclosure. Twenty-eight (73.7%) patients with AF received placement of LAA occlusion device under RT-3D TEE. Eleven cases with single-lobe LAAs were identified using RT-3D TEE, among which 4 showed limited depth. Seventeen cases showed bilobed or multilobed LAA. Seven cases received LAA closure using Lefort and 21 using LAmbre based on the 3D TEE and radiography. The landing zone dimension of the LAA measured by RT-3D TEE Flexi Slice mode was better correlated with the device size used for occlusion (r = 0.90) than 2D TEE (r = 0.88). The interatial septal puncture, the exchange of the sheath, as well as the release of the device were executed under the guidance of RT-3D TEE during the procedure. The average number of closure devices utilized for optimal plugging was (1.11 ± 0.31). There were no clinically unacceptable residual shunts, pericardial effusion, or tamponade right after occlusion. All the patients had the device well

  16. The impact of high-normal blood pressure on left ventricular mechanics: a three-dimensional and speckle tracking echocardiography study.

    Science.gov (United States)

    Tadic, Marijana; Majstorovic, Anka; Pencic, Biljana; Ivanovic, Branislava; Neskovic, Aleksandar; Badano, Luigi; Stanisavljevic, Dejana; Scepanovic, Radisav; Stevanovic, Predrag; Celic, Vera

    2014-04-01

    To assess the presence of subclinical left ventricular myocardial dysfunction in subjects with high-normal blood pressure (BP) and untreated arterial hypertension, using three-dimensional (3D) echocardiography strain analysis. This cross-sectional study included 49 subjects with optimal BP, 50 subjects with high-normal BP, and 50 newly diagnosed untreated hypertensive patients matched by gender and age. All the subjects underwent 24 h blood pressure monitoring and complete two-dimensional and 3D echocardiography examination. The enrolled subjects were grouped according to 24 h systolic BP values, dividing the subjects with optimal BP from those with high-normal BP and the hypertensive patients (cut-off values were 120 and 130 mmHg, respectively). 3D global longitudinal strain was significantly lower in the high-normal BP group and the hypertensive patients, in comparison with the optimal BP group (-20.5 ± 3.3 vs. -18.7 ± 2.8 vs. -17.6 ± 2.7%, p high-normal and the optimal BP groups (10.1° ± 2.4° vs. 10.8° ± 2.6° vs. 13.8° ± 3.1°, p high-normal BP group, to the hypertensive patients (-135 ± 35 vs. -118 ± 31 vs. -102 ± 27°/s, p high-normal BP suffered subclinical impairment of LV mechanics similar as the hypertensive patients.

  17. Quantification of mitral valve morphology with three-dimensional echocardiography--can measurement lead to better management?

    Science.gov (United States)

    Lee, Alex Pui-Wai; Fang, Fang; Jin, Chun-Na; Kam, Kevin Ka-Ho; Tsui, Gary K W; Wong, Kenneth K Y; Looi, Jen-Li; Wong, Randolph H L; Wan, Song; Sun, Jing Ping; Underwood, Malcolm J; Yu, Cheuk-Man

    2014-01-01

    The mitral valve (MV) has complex 3-dimensional (3D) morphology and motion. Advance in real-time 3D echocardiography (RT3DE) has revolutionized clinical imaging of the MV by providing clinicians with realistic visualization of the valve. Thus far, RT3DE of the MV structure and dynamics has adopted an approach that depends largely on subjective and qualitative interpretation of the 3D images of the valve, rather than objective and reproducible measurement. RT3DE combined with image-processing computer techniques provides precise segmentation and reliable quantification of the complex 3D morphology and rapid motion of the MV. This new approach to imaging may provide additional quantitative descriptions that are useful in diagnostic and therapeutic decision-making. Quantitative analysis of the MV using RT3DE has increased our understanding of the pathologic mechanism of degenerative, ischemic, functional, and rheumatic MV disease. Most recently, 3D morphologic quantification has entered into clinical use to provide more accurate diagnosis of MV disease and for planning surgery and transcatheter interventions. Current limitations of this quantitative approach to MV imaging include labor-intensiveness during image segmentation and lack of a clear definition of the clinical significance of many of the morphologic parameters. This review summarizes the current development and applications of quantitative analysis of the MV morphology using RT3DE.

  18. Real-time three-dimensional echocardiographic assessment of mitral valve: Is it really superior to 2D transesophageal echocardiography?

    Science.gov (United States)

    Mukherjee, Chirojit; Tschernich, Heinz; Kaisers, Udo X; Eibel, Sarah; Seeburger, Joerg; Ender, Joerg

    2011-01-01

    Aim of our study was to investigate the feasibility of use and possible additional value of real-time 3D transesophageal echocardiography (RT-3D-TEE) compared to conventional 2D-TEE in patients undergoing elective mitral valve repair. After ethical committee approval, patients were included in this prospective study. After induction of anesthesia, a comprehensive 2D-TEE examination was performed, followed with RT-3D-TEE. The intraoperative surgical finding was used as the gold standard for segmental analysis. Only such segments which were surgically corrected either by resection or insertion of artificial chords were judged pathologic. A total of 50 patients were included in this study; usable data were available from 42 of these patients . Based on the Carpentier classification, the pathology found was type I in 2 (5%) patients, type II in 39 (93%) patients and type IIIb in 1 (2%) patient. We found that 3D imaging of complex mitral disease involving multiple segments, when compared to 2D-TEE did not show any statistically significant difference.RT-3D-TEE did not show any major advantage when compared to conventional 2D-TEE for assessing mitral valve pathology, although further study in a larger population is required to establish the validity of this study.

  19. Late Detection of Left Ventricular Dysfunction Using Two-Dimensional and Three-Dimensional Speckle-Tracking Echocardiography in Patients with History of Nonsevere Acute Myocarditis.

    Science.gov (United States)

    Caspar, Thibault; Fichot, Marie; Ohana, Mickaël; El Ghannudi, Soraya; Morel, Olivier; Ohlmann, Patrick

    2017-08-01

    Acute myocarditis (AM) often involves the left ventricular (LV) subepicardium that might be displayed by cardiac magnetic resonance even late after the acute phase. In the absence of global or regional LV dysfunction, conventional transthoracic echocardiography (TTE) does not accurately identify tissue sequelae of AM. We sought to evaluate the diagnostic value of two-dimensional (2D) and three-dimensional (3D) speckle-tracking echocardiography to identify patients with a history of AM with preserved LV ejection fraction (LVEF). Fifty patients (group 1: age, 31.4 ± 10.5 years; 76% males) with a history of cardiac magnetic resonance-confirmed diagnosis of AM (according to the Lake Louise criteria) were retrospectively identified and then (21.7 ± 23.4 months later) evaluated by complete echocardiography including 2D and 3D speckle-tracking analysis, as well as 50 age- and gender-matched healthy controls (group 2: age, 31.2 ± 9.5 years: 76% males). Patients with a history of severe clinical presentation of AM (sudden death, ventricular arrhythmia, heart failure, alteration of LVEF) were excluded. At diagnosis, peak troponin and C-reactive protein were 11.97 (interquartile range, 4.52-25.92) μg/L and 32.3 (interquartile range, 14.85-70.45) mg/L, respectively. Mean delay between acute phase and follow-up study TTE was 21.7 ± 23.4 months. LVEF was not statistically different between groups (62.1% vs 63.5%, P = .099). Two-dimensional global longitudinal strain (GLS) was lower in magnitude in group 1 (-17.8% vs -22.1%, P speckle-tracking echocardiography, even though LVEF is conserved, adding incremental information over conventional TTE. Copyright © 2017 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

  20. Real-time, interactive animation of deformable two- and three-dimensional objects

    Energy Technology Data Exchange (ETDEWEB)

    Desbrun, Mathieu; Schroeder, Peter; Meyer, Mark; Barr, Alan H.

    2003-06-03

    A method of updating in real-time the locations and velocities of mass points of a two- or three-dimensional object represented by a mass-spring system. A modified implicit Euler integration scheme is employed to determine the updated locations and velocities. In an optional post-integration step, the updated locations are corrected to preserve angular momentum. A processor readable medium and a network server each tangibly embodying the method are also provided. A system comprising a processor in combination with the medium, and a system comprising the server in combination with a client for accessing the server over a computer network, are also provided.

  1. Real-time, interactive animation of deformable two- and three-dimensional objects

    Science.gov (United States)

    Desbrun, Mathieu; Schroeder, Peter; Meyer, Mark; Barr, Alan H.

    2003-06-03

    A method of updating in real-time the locations and velocities of mass points of a two- or three-dimensional object represented by a mass-spring system. A modified implicit Euler integration scheme is employed to determine the updated locations and velocities. In an optional post-integration step, the updated locations are corrected to preserve angular momentum. A processor readable medium and a network server each tangibly embodying the method are also provided. A system comprising a processor in combination with the medium, and a system comprising the server in combination with a client for accessing the server over a computer network, are also provided.

  2. The advantages of live/real time three-dimensional transesophageal echocardiography in the assessment of tricuspid valve infective endocarditis.

    Science.gov (United States)

    Sungur, Aylin; Hsiung, Ming C; Meggo Quiroz, Luis D; Oz, Tuğba Kemaloğlu; Haj Asaad, Ayman; Joshi, Deepak; Dönmez, Cevdet; Güvenç, Tolga S; Nanda, Navin C

    2014-11-01

    Currently, tricuspid valve infective endocarditis (TVIE) is encountered in daily clinical practice more frequently due to the increasing prevalence of illicit intravenous drug use and the implantation of intracardiac devices. In this study, we compared findings from intra-operative live/real time three-dimensional transesophageal echocardiograms (3DTEE) and two-dimensional transesophageal echocardiograms (2DTEE) of 10 patients who underwent surgery for native tricuspid valve (TV) endocarditis. Unlike 2DTEE, 3DTEE allowed en face visualization of the 3 TV leaflets from both, atrial and ventricular aspects, in 9 of the 10 cases. In the remaining patient, in whom 3DTEE could not identify all 3 leaflets en face, the TV was found essentially destroyed at surgery. Using 3DTEE, the number of vegetations was accurately reported when compared with the surgical record. Furthermore, the orientation of each vegetation was the same as noted in the surgical findings. 2DTEE missed the identification of vegetations in 5 patients. The attachment site of vegetations to the TV were also not characterized by 2DTEE in 5 patients. In all 10 cases, 3DTEE characterized the vegetations more accurately with larger dimensions, including those in the azimuthal axis, and volumes. In addition, a perivalvular abscess that lead to surgical intervention was identified by 3DTEE, however, missed by 2DTEE. In conclusion, 3DTEE allows en face visualization of the TV apparatus permitting accurate description of the number and dimensions of vegetations identified by our surgical standard, which ultimately informs patients' prognosis and dictates the timing and planning for surgical intervention. Its use should be in conjunction with 2DTEE when evaluating TVIE.

  3. Plane-wave superpositions defined by orthonormal scalar functions on two- and three-dimensional manifolds

    Science.gov (United States)

    Borzdov

    2000-04-01

    Vector plane-wave superpositions defined by a given set of orthonormal scalar functions on a two- or three-dimensional manifold-beam manifold-are treated. We present a technique for composing orthonormal beams and some other specific types of fields such as three-dimensional standing waves, moving and evolving whirls. It can be used for any linear fields, in particular, electromagnetic fields in complex media and elastic fields in crystals. For electromagnetic waves in an isotropic medium or free space, unique families of exact solutions of Maxwell's equations are obtained. The solutions are illustrated by calculating fields, energy densities, and energy fluxes of beams defined by the spherical harmonics. It is shown that the obtained results can be used for a transition from the plane-wave approximation to more accurate models of real incident beams in free-space techniques for characterizing complex media. A mathematical formalism convenient for the treatment of various beams defined by the spherical harmonics is presented.

  4. A general theory of two- and three-dimensional rotational flow in subsonic and transonic turbomachines

    Science.gov (United States)

    Wu, Chung-Hua

    1993-01-01

    This report represents a general theory applicable to axial, radial, and mixed flow turbomachines operating at subsonic and supersonic speeds with a finite number of blades of finite thickness. References reflect the evolution of computational methods used, from the inception of the theory in the 50's to the high-speed computer era of the 90's. Two kinds of relative stream surfaces, S(sub 1) and S(sub 2), are introduced for the purpose of obtaining a three-dimensional flow solution through the combination of two-dimensional flow solutions. Nonorthogonal curvilinear coordinates are used for the governing equations. Methods of computing transonic flow along S(sub 1) and S(sub 2) stream surfaces are given for special cases as well as for fully three-dimensional transonic flows. Procedures pertaining to the direct solutions and inverse solutions are presented. Information on shock wave locations and shapes needed for computations are discussed. Experimental data from a Deutsche Forschungs- und Versuchsanstalt fur Luft- und Raumfahrt e.V. (DFVLR) rotor and from a Chinese Academy of Sciences (CAS) transonic compressor rotor are compared with the computed flow properties.

  5. Two- and Three-Dimensional Probes of Parity in Primordial Gravity Waves

    Science.gov (United States)

    Masui, Kiyoshi Wesley; Pen, Ue-Li; Turok, Neil

    2017-06-01

    We show that three-dimensional information is critical to discerning the effects of parity violation in the primordial gravity-wave background. If present, helical gravity waves induce parity-violating correlations in the cosmic microwave background (CMB) between parity-odd polarization B modes and parity-even temperature anisotropies (T ) or polarization E modes. Unfortunately, E B correlations are much weaker than would be naively expected, which we show is due to an approximate symmetry resulting from the two-dimensional nature of the CMB. The detectability of parity-violating correlations is exacerbated by the fact that the handedness of individual modes cannot be discerned in the two-dimensional CMB, leading to a noise contribution from scalar matter perturbations. In contrast, the tidal imprints of primordial gravity waves fossilized into the large-scale structure of the Universe are a three-dimensional probe of parity violation. Using such fossils the handedness of gravity waves may be determined on a mode-by-mode basis, permitting future surveys to probe helicity at the percent level if the amplitude of primordial gravity waves is near current observational upper limits.

  6. Two- and Three-Dimensional All-Carbon Nanomaterial Assemblies for Tissue Engineering and Regenerative Medicine.

    Science.gov (United States)

    Lalwani, Gaurav; Patel, Sunny C; Sitharaman, Balaji

    2016-06-01

    Carbon nanomaterials such as carbon nanotubes and graphene have gained significant interest in the fields of materials science, electronics and biomedicine due to their interesting physiochemical properties. Typically these carbon nanomaterials have been dispersed in polymeric matrices at low concentrations to improve the functional properties of nanocomposites employed as two-dimensional (2D) substrates or three-dimensional (3D) porous scaffolds for tissue engineering applications. There has been a growing interest in the assembly of these nanomaterials into 2D and 3D architectures without the use of polymeric matrices, surfactants or binders. In this article, we review recent advances in the development of 2D or 3D all-carbon assemblies using carbon nanotubes or graphene as nanoscale building-block biomaterials for tissue engineering and regenerative medicine applications.

  7. Periapical repair following endodontic surgery: two- and three-dimensional imaging evaluation methods.

    Science.gov (United States)

    Jorge, Érica Gouveia; Tanomaru-Filho, Mario; Guerreiro-Tanomaru, Juliane Maria; Reis, José Maurício dos Santos Nunes; Spin-Neto, Rubens; Gonçalves, Marcelo

    2015-01-01

    This study quantitatively assessed the periapical bone repair following endodontic surgery, using planimetric evaluation based on two- (conventional and digital intraoral radiographic images - IRs) and three-dimensional (cone beam computed tomography - CBCT) evaluation. Eleven maxillary anterior teeth (of 11 patients) with periapical bone lesions and indication for surgical endodontic treatment were selected. IRs and CBCT images were acquired before the endodontic surgery, and 48 h, 4, and 8-months after the surgery. In each period of evaluation, the area (mm2) of the bone lesion was measured in the images, and the values for the three methods were compared. The area in the CBCT images was measured in the mesio-distal sections comprising the largest diameter of the lesion. Data were submitted to repeated measures 2-way ANOVA and t-tests with Bonferroni correction. There was significant difference between the periods of evaluation (p=0.002) regarding the assessed periapical bone lesion area. There was no statistically significant difference between the methods of evaluation (p=0.023). In the CBCT images the lesion areas were 10% larger than those observed in the conventional IRs (22.84 mm2) and 15% larger than those observed in the digital IRs (21.48 mm2). From the baseline (40.12 mm2) to 4 (20.06 mm2) and 8-months (9.40 mm2), reductions of 50 and 77% in the lesion area, respectively, were observed (p<0.0001). From 4 to 8-months, this value was 53%. Progressive bone repair could be seen from 48 h to 8-months following endodontic surgery based on two- (conventional and digital IRs) and three-dimensional (CBCT) evaluation. CBCT images provided results similar to those assessed by means of IRs.

  8. Evaluation of left atrial volume and function in systemic sclerosis patients using speckle tracking and real-time three-dimensional echocardiography.

    Science.gov (United States)

    Ataş, Halil; Kepez, Alper; Tigen, Kürşat; Samadov, Fuad; Özen, Gülsen; Cincin, Altuğ; Sünbül, Murat; Bozbay, Mehmet; Direşkeneli, Haner; Başaran, Yelda

    2016-05-01

    The aim of the present study was to evaluate left atrial (LA) volume and functions using real-time three-dimensional echocardiography (RT3DE) and speckle tracking in systemic sclerosis (SSc) patients. The study was designed as a cross-sectional observational study. We studied 41 consecutive SSc patients (38 females, mean age: 49.5±11.6 years) and 38 healthy controls (35 females, mean age: 48.5±10.8 years). Patients with evidence or history of cardiovascular disease and patients with risk factors as hypertension, diabetes and chronic renal failure were excluded from the study. All study subjects underwent standard echocardiography; LA speckle tracking and RT3DE was performed to assess LA volume and phasic functions. Differences between numeric variables were tested using the independent sample Student's t-test or Mann-Whitney U test, where appropriate. There were no significant differences between SSC patients and controls regarding left ventricular (LV) systolic functions and two-dimensional (2-D) atrial diameters. Presence of LV diastolic dysfunction (LVDD) was evaluated and graded according to recommendations of the American Society of Echocardiography. Accordingly, LVDD was observed to be significantly more frequent in SSc patients; 16 SSc patients (39%) and 5 controls (12.8%) were observed to have LVDD (p=0.007). With regard to results obtained from RT3DE, LA maximum, minimum, and before atrial contraction volumes were significantly higher (40.5±14.6 vs. 32.6±8.9, 15.5±8.4 vs. 9.9±3.5 and 28.7±11.7 vs. 21.4±7.0 mL respectively, pspeckle tracking echocardiography, atrial peak-systolic longitudinal strain (ε), early negative strain rate (SR), late negative SR, and peak positive SR values were observed to be significantly lower in SSc patients. LA volumes were significantly increased, and LA reservoir, conduit, and contractile functions were significantly impaired in SSc patients compared with controls. LA volume and functional analyses with RT3DE and

  9. Two-component Dirac-like Hamiltonian for generating quantum walk on one-, two- and three-dimensional lattices.

    Science.gov (United States)

    Chandrashekar, C M

    2013-10-03

    From the unitary operator used for implementing two-state discrete-time quantum walk on one-, two- and three- dimensional lattice we obtain a two-component Dirac-like Hamiltonian. In particular, using different pairs of Pauli basis as position translation states we obtain three different form of Hamiltonians for evolution on one-dimensional lattice. We extend this to two- and three-dimensional lattices using different Pauli basis states as position translation states for each dimension and show that the external coin operation, which is necessary for one-dimensional walk is not a necessary requirement for a walk on higher dimensions but can serve as an additional resource to control the dynamics. The two-component Hamiltonian we present here for quantum walk on different lattices can serve as a general framework to simulate, control, and study the dynamics of quantum systems governed by Dirac-like Hamiltonian.

  10. Nonlocal continuous models for forced vibration analysis of two- and three-dimensional ensembles of single-walled carbon nanotubes

    Science.gov (United States)

    Kiani, Keivan

    2014-06-01

    Novel nonlocal discrete and continuous models are proposed for dynamic analysis of two- and three-dimensional ensembles of single-walled carbon nanotubes (SWCNTs). The generated extra van der Waals forces between adjacent SWCNTs due to their lateral motions are evaluated via Lennard-Jones potential function. Using a nonlocal Rayleigh beam model, the discrete and continuous models are developed for both two- and three-dimensional ensembles of SWCNTs acted upon by transverse dynamic loads. The capabilities of the proposed continuous models in capturing the vibration behavior of SWCNTs ensembles are then examined through various numerical simulations. A reasonably good agreement between the results of the continuous models and those of the discrete ones is also reported. The effects of the applied load frequency, intertube spaces, and small-scale parameter on the transverse dynamic responses of both two- and three-dimensional ensembles of SWCNTs are explained. The proposed continuous models would be very useful for dynamic analyses of large populated ensembles of SWCNTs whose discrete models suffer from both computational efforts and labor costs.

  11. Left ventricular mechanics in repaired tetralogy of Fallot with and without pulmonary valve replacement: analysis by three-dimensional speckle tracking echocardiography.

    Directory of Open Access Journals (Sweden)

    Shu-Na Li

    Full Text Available BACKGROUND: Altered septal curvature and left ventricular (LV geometry secondary to right ventricular (RV dilation render two-dimensional assessment of LV mechanics difficult in repaired tetralogy of Fallot (TOF patients. The novel three-dimensional (3D speckle tracking echocardiography enables comprehensive evaluation of true 3D LV mechanics. METHODS AND RESULTS: Seventy-six patients aged 23.6 ± 8.3 years, 55 with isolated repair (group I and 21 with subsequent pulmonary valve replacement (group II, and 34 healthy controls were studied. Three-dimensional volume datasets were acquired for assessment of LV global and regional 3D strain, systolic dyssynchrony index (SDI, twist, twist gradient (twist/LV length, and ejection fraction. A global performance index was calculated as (global 3D strain•twist gradient/SDI. The septal curvature and LV eccentricity were determined from the mid-ventricular short-axis. Compared with controls, group I and II patients had significantly reduced LV global 3D strain, LV twist, twist gradient, septal curvature, and global performance index, and greater LV systolic and diastolic eccentricity and SDI (all p<0.05. All but the four apical LV segments in patients had reduced regional 3D strain compared with controls (all p<0.05. Septal curvature correlated with LV global 3D strain (r=0.41, p<0.001, average septal strain (r=0.38, p<0.001, twist (r=0.32, p<0.001, twist gradient (r=0.33, p<0.001, and global performance index (r=0.43, p<0.001. CONCLUSIONS: Adverse 3D LV mechanics as characterized by impaired global and regional 3D systolic strain, mechanical dyssynchrony, and reduced twist is related to reduced septal curvature in repaired TOF patients with and without pulmonary valve replacement.

  12. Left ventricular myocardial strain by three-dimensional speckle-tracking echocardiography in healthy subjects: reference values and analysis of their physiologic and technical determinants.

    Science.gov (United States)

    Muraru, Denisa; Cucchini, Umberto; Mihăilă, Sorina; Miglioranza, Marcelo Haertel; Aruta, Patrizia; Cavalli, Giacomo; Cecchetto, Antonella; Padayattil-Josè, Seena; Peluso, Diletta; Iliceto, Sabino; Badano, Luigi P

    2014-08-01

    Despite growing interest in applying three-dimensional (3D) speckle-tracking echocardiography (STE) to measure left ventricular (LV) myocardial deformation in various diseases, normative values for 3D speckle-tracking echocardiographic parameters and the effects of demographic, hemodynamic, and technical factors on these values are unknown. In 265 healthy volunteers (age range, 18-76; 57% women), longitudinal strain (3DLε), circumferential strain (3DCε), radial strain (3DRε), and area strain (3DAε) were measured by using vendor-specific (Vsp) 3D speckle-tracking echocardiographic equipment. LV strain was also measured by using Vsp two-dimensional (2D) and vendor-independent 3D speckle-tracking echocardiographic software packages, for comparison. Reference values (lower limit of normality) for Vsp 3D STE were -17% to -21% (-15%) for 3DLε, -17% to -20% (-14%) for 3DCε, -31% to -36% (-26%) for 3DAε, and 47% to 59% (38%) for 3DRε. Three-dimensional longitudinal strain decreased, whereas 3DCε increased, with aging (P < .003), with different trends in men and women. Men had lower 3DLε, 3DRε, 3DAε, and 2D longitudinal strain than women (P < .02). LV 3D strain parameters were also influenced by LV volumes and mass, image quality, and temporal resolution (P < .02). Reference values obtained by Vsp 2D STE were -20% to -23% (-18%) for 2D longitudinal strain, -20% to -24% (-17%) for 2D circumferential strain, and 39% to 54% (28%) for 2D radial strain (P < .001 vs Vsp 3D STE). Significantly different 3DCε and 3DRε values were obtained with vendor-independent versus Vsp 3D STE (P < .001). In healthy subjects, reference values of LV 3D strain parameters were significantly influenced by demographic, cardiac, and technical factors. Limits of normality of LV strain by Vsp 3D STE should not be used interchangeably with Vsp 2D STE or with Vin 3D STE software. Copyright © 2014 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.

  13. Two-and Three-Dimensional Simulations of Beetle Hind Wing Flapping during Free Forward Flight

    Institute of Scientific and Technical Information of China (English)

    Tuyen Quang Le; Tien Van Truong; Hieu Trung Tran; Soo Hyung Park; Jin Hwan Ko; Hoon Cheol Park; Kwang Joon Yoon

    2013-01-01

    Aerodynamic characteristic of the beetle,Trypoxylus dichotomus,which has a pair of elytra (forewings) and hind wings,is numerically investigated.Based on the experimental results of wing kinematics,two-dimensional (2D) and three-dimensional (3D) computational fluid dynamic simulations were carried out to reveal aerodynamic performance of the hind wing.The roles of the spiral Leading Edge Vortex (LEV) and the spanwise flow were clarified by comparing 2D and 3D simulations.Mainly due to pitching down of chord line during downstroke in highly inclined stroke plane,relatively high averaged thrust was produced in the free forward flight of the beetle.The effects of the local corrugation and the camber variation were also investigated for the beetle's hind wings.Our results show that the camber variation plays a significant role in improving both lift and thrust in the flapping.On the other hand,the local corrugation pattern has no significant effect on the aerodynamic force due to large angle of attack during flapping.

  14. Prenatal diagnosis of a fetus with ring chromosomal 15 by two- and three-dimensional ultrasonography.

    Science.gov (United States)

    Britto, Ingrid Schwach Werneck; Regina Silva Herbest, Sandra; Tedesco, Giselle Darahem; Drummond, Carolina Leite; Bussamra, Luiz Claudio Silva; Araujo Júnior, Edward; Ruano, Rodrigo; Ruano, Simone Hernandez; Aldrighi, José Mendes

    2014-01-01

    We report on a prenatal diagnosis of ring chromosome 15 in a fetus with left congenital diaphragmatic hernia (CDH) and severe intrauterine growth restriction (IUGR). A 31-year-old woman, gravida 2 para 1, was referred because of increased nuchal translucency at gestational age of 13 weeks. Comprehensive fetal ultrasound examination was performed at 19 weeks revealing an early onset IUGR, left CDH with liver herniation, and hypoplastic nasal bone. Three-dimensional ultrasound (rendering mode) showed low set ears and depressed nasal bridge. Amniocentesis was performed with a result of a 46,XX,r(15) fetus after a cytogenetic study. A 1,430 g infant (less than third percentile) was born at 36 weeks. The infant presented with respiratory failure and died at 2 h of life. Postnatal karyotype from the umbilical cord confirmed the diagnosis of 15-ring chromosome. We described the main prenatal 2D- and 3D-ultrasound findings associated with ring chromosome 15. The interest in reporting the present case is that CDH can be associated with the diagnosis of 15-ring chromosome because the critical location of the normal diaphragm development is at chromosome 15q26.1-q26.2.

  15. Value of left ventricular regional ejection fraction determined by real-time three-dimensional echocardiography in diagnosis of aneurysm: compared with left ventriculography

    Institute of Scientific and Technical Information of China (English)

    LI Xiu-chang; YAN Cheng-jun; YAO Gui-hua; ZHANG Mei; LI Ji-fu; ZHANG Yun

    2009-01-01

    Background Regional ejection fraction (EF_R) measured by real-time three-dimensional echocardiography (RT-3DE)provides a novel method for quantifying left-ventricular (LV) regional systolic function. We aimed to explore the diagnostic value of regional ejection fraction (EFR) derived from RT-3DE in detecting LV aneurysms in patients with myocardial infarction. Methods Thirty-eight patients with myocardial infarction were prospectively enrolled and underwent electrocardiography (ECG), two-dimensional echocardiography (2-DE), RT-3DE and left ventriculography (LVG).Subjects with a negative EFR in at least one segment on RT-3DE were considered as having a ventricular aneurysm. We compared the sensitivity, specificity, Youden's index, and positive and negative predictive values of ECG, 2-DE and RT-3DE in determining LV aneurysm with detection by LVG.Results On LVG an LV aneurysm was diagnosed in 16 (42.1%) patients. The sensitivity and specificity were 62.5% and 86.4% for ECG, 81.2% and 95.4% for 2-DE, and 100.0% and 90.9% for RT-3DE in diagnosing LV aneurysm. Youden's indexes for ECG, 2-DE and RT-3DE were 0.49, 0.77 and 0.91, respectively. Positive and negative predictive values were 76.9% and 76.0% for ECG, 92.9% and 87.5% for 2-DE, and 88.9% and 100.0% for RT-3DE. Conclusions RT-3DE-derived EFR provides a novel, reliable index in the diagnosis of LV aneurysm and has excellent sensitivity and specificity.

  16. Percutaneous transcatheter closure of atrial septal defects: initial single-centre experience and follow-up results. Initial experience with three-dimensional echocardiography.

    Science.gov (United States)

    De Ridder, Serge; Suttorp, Maarten-Jan; Ernst, Sjef M P G; Six, Jacob A; Mannaerts, Herman F J; Kamp, Otto; Plokker, Thijs H W M; Jaarsma, Wybren

    2005-04-01

    Registry to report our single-centre experience in closing defects of the atrial septum. Between 1996 and 2001, transcatheter device closure of significant atrial septal defects was performed in 32 adults (mean age 45.1 years, range from 15 to 76 years), using different device types. Six patients had a patent foramen ovale (PFO) and 26 patients had a secundum atrial septal defect (ASD II). Defects were selected by means of two-dimensional transoesophageal echocardiography (2D TOE). For 12 defects additional three-dimensional transoesophageal echocardiography (3D TOE) was performed. Mean balloon-stretched diameter was 19.3 mm (range from 11 to 24 mm). A device was successfully placed in all PFO patients (100%) without complications at follow-up. Successful immediate device placement occurred in 24 out of 26 ASD patients. Two immediate placement failures, 1 device embolisation and 1 device non-fixation, occurred and required urgent surgery. There was 1 patient with pericardial effusion after the intervention, requiring pericardiocentesis. Three late placement failures occurred: 2 device embolisations and 1 device dislocation. Clinical success after 3 to 6 months follow-up, defined as the absence of shunt or small shunt, was achieved in all 6 PFO patients and in 21 out of 23 ASD patients (1 device embolisation, requiring surgery, occurred before follow-up was completed). Two patients with significant shunt, 1 late device dislocation and 1 late device embolisation, underwent elective surgery. For patient selection, 3D TOE proved useful in the evaluation of large and/or complex defects. Transcatheter device closure of carefully selected atrial septal defects is an alternative to surgery. Although the results are promising, surgical back-up is often needed.

  17. Methodological study on real-time three-dimensional echocardiography and its application in the diagnosis of complex congenital heart disease

    Institute of Scientific and Technical Information of China (English)

    CHEN Guo-zhen; HUANG Guo-ying; LIANG Xue-cun; MA Xiao-jing; CHEN Wei-da; TAO Zi-yu; LIN Qi-shan

    2006-01-01

    Background Real-time three-dimensional echocardiography (RT-3DE) has made revolutionized improvements of cardiac imaging during the past few years. However, there is no standard examination method for RT-3DE so far. This study aimed to establish the diagnostic method of RT-3DE and evaluate its application in the diagnosis of complex congenital heart diseases (CHD).Methods Fifty patients with complex CHD were examined by RT-3DE with modes of Live 3DE and Full Volume. A series of novel volumetric views combined with Van Praagh sequential segmental approach were introduced to reveal the pathological morphology of the hearts, which were compared with the findings of two-dimensional echocardiography (2DE), angiography and cardiac surgery.Results In 50 patients, 190 image acquisitions of Full Volume were performed at several acoustic windows including subcostal, apical and parasternal regions. Among them, 94.2% (179/190) of image acquisitions were successful. Most sectional volumetric views could be clearly displayed in 92.6% of the successful image acquisitions. However, sectional volumetric views could not be clearly displayed in 7.4%, which was mainly due to poor perspective conditions of examination location, improper instrument multi-parameter setting and insufficient information of whole heart captured in Full Volume acquisitions. As compared with surgical findings and angiography, RT-3DE made correction to the diagnoses in 2 cases including 1 with corrected transposition of the great arteries and the other with single atrium and mitral cleft. The diagnoses initially made by 2DE for these 2 patients were double outlet right ventricle with transposition of the great arteries and complete atrio-ventricular septal defect.Conclusions RT-3DE can clearly display the pathological morphology of complex CHD by a series of novel volumetric views combined with sequential segmental approach through providing more spatial informative cardiovascular structures, which provides a

  18. Comparison of two- and three-dimensional measurement of the Cobb angle in scoliosis.

    Science.gov (United States)

    Lechner, Ricarda; Putzer, David; Dammerer, Dietmar; Liebensteiner, Michael; Bach, Christian; Thaler, Martin

    2017-05-01

    The Cobb angle as an objective measure is used to determine the progression of deformity, and is the basis in the planning of conservative and surgical treatment. However, studies have shown that the Cobb angle has two limitations: an inter- and intraobserver variability of the measurement is approximately 3-5 degrees, and high variability regarding the definition of the end vertebra. Scoliosis is a three-dimensional (3D) pathology, and 3D pathologies cannot be completely assessed by two-dimensional (2D) methods, like 2D radiography. The objective of this study was to determine the intraobserver and interobserver reliability of end vertebra definition and Cobb angle measurement using X-rays and 3D computer tomography (CT) reconstructions in scoliotic spines. To assess interoberver variation the Cobb angle and the end vertebra were assessed by five observers in 55 patients using X-rays and 3D CT reconstructions. Definition of end vertebra and measurement of the Cobb angle was repeated two times with a three-week interval. Intraclass correlation coefficients (ICC) were used to determine the interobserver and intraobserver reliabilities. 95% prediction limits were provided for measurement errors. Intraclass correlation coefficient (ICC) showed excellent reliability for both methods. The measured Cobb angle was on average 9.2 degrees larger in the 3D CT group (72.8°, range 30-144) than on 2D radiography (63.6°, range 24-152). In scoliosis treatment it is very essential to determine the curve magnitude, which is larger in a 3D measurement compared to 2D radiography.

  19. Comparison of two-and three-dimensional modeling of invert trap for sewer solid management

    Institute of Scientific and Technical Information of China (English)

    Tsewang Thinglas; Deo Raj Kaushal

    2008-01-01

    In the present study, five different invert trap configurations (rectangular with and without lids on both sides; trapezoidal, trapezoidal with rectangular base and rectangular with trapezoidal base with lids on both sides) were simulated for both two-dimensional (2D) and three-dimensional (3D) flow conditions for three sediment types (sand, styrocell and plastic beads) at six flow rates (0.35, 0.70, 1.05, 1.35, 4.55 and 9.95L/s) for each trap. Computational fluid dynamics (CFD)-based modeling using FLUENT software with Renormalization Group (RNG) k-ε model along with discrete phase model (DPM) were used in the simulations. A hexagonal/tetrahedral and map-type non-uniform grid was chosen to discretize the entire computational domain and a control volume finite difference method was used to solve the governing equations. The flow rates selected in the present study cover the entire range of flow rate expected for dry weather and monsoon. The simulation is capable of differentiating between 2D and 3D modeling of particle trajectories, the effects of flow rate and trap geometry on flow patterns developed in the trap. The sediment retention ratio for 2D is higher than that for 3D modeling for all flow conditions, particle types and model geometry due to inclusion of lateral effects in 3D modeling. The invert trap having rectangular shape with trapezoidal base is found to be the most efficient configuration in both 2D and 3D modeling.

  20. New Parameter Derived from Three-Dimensional Speckle-Tracking Echocardiography for the Estimation of Left Ventricular Filling Pressure in Nondilated Hearts.

    Science.gov (United States)

    Sakurai, Daisuke; Asanuma, Toshihiko; Masuda, Kasumi; Koriyama, Hikaru; Nakatani, Satoshi

    2017-05-01

    E/e' is clinically useful for the noninvasive assessment of left ventricular (LV) filling pressure. However, its use in some conditions is controversial, and angle dependence of the Doppler measurement and preload dependence of mitral e' in nondilated hearts represent major problems. The ratio of early filling rate derived from the time derivative of LV volume to early diastolic strain rate (FRe/SRe), similar to E/e', by three-dimensional (3D) speckle-tracking echocardiography has the potential to address such limitations. This study investigated whether FRe/SRe could estimate acute changes in LV filling pressure using the models of volume overload and myocardial ischemia in the nondilated heart. In 25 dogs, hemodynamic conditions were varied by acute volume overload and coronary occlusion. FRe and SRe were obtained from the same beat and automatically analyzed by the 3D speckle-tracking method, and global SRe was measured from longitudinal (L-SRe), circumferential (C-SRe), and area strain rate (A-SRe). E/e' was measured by two-dimensional echocardiography. LV pressure was derived from a micromanometer catheter and recorded simultaneously with the acquisition of the 3D images. Mitral e' and L-SRe varied by changes in preload, whereas C-SRe and A-SRe did not. C-SRe and A-SRe were more strongly correlated with the time constant of LV relaxation than mitral e' and L-SRe. FRe/C-SRe and FRe/A-SRe had relatively high correlations with LV preatrial contraction (pre-A) pressure and end-diastolic pressure, but E/e' and FRe/L-SRe did not. Receiver operating characteristics curve analysis showed that FRe/C-SRe and FRe/A-SRe had larger areas under the curve for the estimation of increased LV filling pressure. The novel parameter FRe/SRe has potential as a surrogate marker of LV filling pressure. Especially in nondilated hearts, FRe/C-SRe and FRe/A-SRe may be useful to more accurately predict LV filling pressure than E/e', although their applicability in dilated hearts

  1. New digital measurement methods for left ventricular volume using real-time three-dimensional echocardiography: comparison with electromagnetic flow method and magnetic resonance imaging

    Science.gov (United States)

    Qin, J. J.; Jones, M.; Shiota, T.; Greenberg, N. L.; Firstenberg, M. S.; Tsujino, H.; Zetts, A. D.; Sun, J. P.; Cardon, L. A.; Odabashian, J. A.; Flamm, S. D.; White, R. D.; Panza, J. A.; Thomas, J. D.

    2000-01-01

    AIM: The aim of this study was to investigate the feasibility and accuracy of using symmetrically rotated apical long axis planes for the determination of left ventricular (LV) volumes with real-time three-dimensional echocardiography (3DE). METHODS AND RESULTS: Real-time 3DE was performed in six sheep during 24 haemodynamic conditions with electromagnetic flow measurements (EM), and in 29 patients with magnetic resonance imaging measurements (MRI). LV volumes were calculated by Simpson's rule with five 3DE methods (i.e. apical biplane, four-plane, six-plane, nine-plane (in which the angle between each long axis plane was 90 degrees, 45 degrees, 30 degrees or 20 degrees, respectively) and standard short axis views (SAX)). Real-time 3DE correlated well with EM for LV stroke volumes in animals (r=0.68-0.95) and with MRI for absolute volumes in patients (r-values=0.93-0.98). However, agreement between MRI and apical nine-plane, six-plane, and SAX methods in patients was better than those with apical four-plane and bi-plane methods (mean difference = -15, -18, -13, vs. -31 and -48 ml for end-diastolic volume, respectively, Pmeasurement methods of real-time 3DE correlated well with reference standards for calculating LV volumes. Balancing accuracy and required time for these LV volume measurements, the apical six-plane method is recommended for clinical use.

  2. Novel Two- and Three-Dimensional Organometallic-Organic Hybrid Materials Based on Polyphosphorus Complexes.

    Science.gov (United States)

    Attenberger, Bianca; Peresypkina, Eugenia V; Scheer, Manfred

    2015-07-20

    The reaction of the silver salt Ag[Al{OC(CF3)3}4] (1) with the P2 ligand complex [Cp2Mo2(CO)4(η(2)-P2)] (2) and the organic ditopic linker trans-1,2-di(pyridine-4-yl)ethene (dpe) results in the formation of four novel organometallic-organic hybrid compounds. Depending on the reaction conditions, the two-dimensional networks [{Cp2Mo2(CO)4(μ4,η(1:1:2:2)-P2)}(μ,η(1:1)-C12H10N2)Ag]n[Al{OC(CF3)3}4]n·0.075nCH2Cl2·1.425nC6H6 (3) and [{Cp2Mo2(CO)4(μ3,η(2:2:2)-P2)}2(μ,η(1:1)-C12H10N2)3Ag2]n[Al{OC(CF3)3}4]2n·2nC7H8 (4) are accessible. The latter shows a two-dimensional (2D) → 2D interpenetration structure. Furthermore, the formation of a unique three-dimensional polymer [{Cp2Mo2(CO)4(μ4,η(1:1:2:2)-P2)}(μ,η(1:1)-C12H10N2)Ag]n[Al{OC(CF3)3}4]n·0.3nCH2Cl2 (5b) together with another 2D polymer [{Cp2Mo2(CO)4(μ4,η(1:1:2:2)-P2)}(μ,η(1:1)-C12H10N2)3Ag2]n[Al{OC(CF3)3}4]2n·0.75CH2Cl2·0.5C7H8 (5a) was observed. In three of these polymers, unprecedented organometallic nodes were realized including one, two, or even four silver cations. All products were characterized by X-ray structural analysis and classified by the structural characteristics in three different network topologies.

  3. Interferograms, schlieren, and shadowgraphs constructed from real- and ideal-gas, two- and three-dimensional computed flowfields

    Science.gov (United States)

    Yates, Leslie A.

    1993-01-01

    The construction of interferograms, schlieren, and shadowgraphs from computed flowfield solutions permits one-to-one comparisons of computed and experimental results. A method of constructing these images from both ideal- and real-gas, two and three-dimensional computed flowfields is described. The computational grids can be structured or unstructured, and multiple grids are an option. Constructed images are shown for several types of computed flows including nozzle, wake, and reacting flows; comparisons to experimental images are also shown. In addition, th sensitivity of these images to errors in the flowfield solution is demonstrated, and the constructed images can be used to identify problem areas in the computations.

  4. Coexistence of Two- and Three-dimensional Shubnikov-de Haas Oscillations in Ar^+ -irradiated KTaO_3

    Energy Technology Data Exchange (ETDEWEB)

    Harashima, S.; Bell, C.; Kim, M.; Yajima, T.; Hikita, Y.; Hwang, H.Y.

    2012-05-16

    We report the electron doping in the surface vicinity of KTaO{sub 3} by inducing oxygen-vacancies via Ar{sup +}-irradiation. The doped electrons have high mobility (> 10{sup 4} cm{sup 2}/Vs) at low temperatures, and exhibit Shubnikov-de Haas oscillations with both two- and three-dimensional components. A disparity of the extracted in-plane effective mass, compared to the bulk values, suggests mixing of the orbital characters. Our observations demonstrate that Ar{sup +}-irradiation serves as a flexible tool to study low dimensional quantum transport in 5d semiconducting oxides.

  5. Scaling of current distributions in variable-range hopping transport on two- and three-dimensional lattices

    Science.gov (United States)

    Pasveer, W. F.; Bobbert, P. A.; Huinink, H. P.; Michels, M. A. J.

    2005-11-01

    From extensive computer simulations of variable-range hopping (VRH) transport of charges on regular two- and three-dimensional lattices with random site energies we calculate the average contribution to the total current of hops over a certain distance and with a certain hop energy. We find that the resulting current distribution is a universal function of scaled distance and energy variables. We discuss this scaling in the light of the original arguments of Mott and percolation arguments to explain the temperature dependence of the VRH conductivity.

  6. Fast randomized point location without preprocessing in two- and three-dimensional Delaunay triangulations

    Energy Technology Data Exchange (ETDEWEB)

    Muecke, E.P.; Saias, I.; Zhu, B.

    1996-05-01

    This paper studies the point location problem in Delaunay triangulations without preprocessing and additional storage. The proposed procedure finds the query point simply by walking through the triangulation, after selecting a good starting point by random sampling. The analysis generalizes and extends a recent result of d = 2 dimensions by proving this procedure to take expected time close to O(n{sup 1/(d+1)}) for point location in Delaunay triangulations of n random points in d = 3 dimensions. Empirical results in both two and three dimensions show that this procedure is efficient in practice.

  7. ADFNE: Open source software for discrete fracture network engineering, two and three dimensional applications

    Science.gov (United States)

    Fadakar Alghalandis, Younes

    2017-05-01

    Rapidly growing topic, the discrete fracture network engineering (DFNE), has already attracted many talents from diverse disciplines in academia and industry around the world to challenge difficult problems related to mining, geothermal, civil, oil and gas, water and many other projects. Although, there are few commercial software capable of providing some useful functionalities fundamental for DFNE, their costs, closed code (black box) distributions and hence limited programmability and tractability encouraged us to respond to this rising demand with a new solution. This paper introduces an open source comprehensive software package for stochastic modeling of fracture networks in two- and three-dimension in discrete formulation. Functionalities included are geometric modeling (e.g., complex polygonal fracture faces, and utilizing directional statistics), simulations, characterizations (e.g., intersection, clustering and connectivity analyses) and applications (e.g., fluid flow). The package is completely written in Matlab scripting language. Significant efforts have been made to bring maximum flexibility to the functions in order to solve problems in both two- and three-dimensions in an easy and united way that is suitable for beginners, advanced and experienced users.

  8. Comparison between two and three-dimensional POD in a turbulent boundary layer using multi-plane stereoscopic PIV

    Science.gov (United States)

    Liberzon, Alex; Gurka, Roi; Hetsroni, Gad

    2011-12-01

    A comparison between two- and three-dimensional analyses using proper orthogonal decomposition (POD) is performed. The investigated flow field is a turbulent boundary layer in a flume. The decomposition is applied to the vorticity fields measured using a multi-plane stereoscopic particle image velocimetry (PIV) measurement system. The decomposition was applied using two methods: A) two-dimensional slices of the data that were used separately in a so-called slice-POD, and B) as a volumetric dataset that provides 3D-POD modes. Linear combination of the first three modes, energy distribution and reconstruction of snapshots are compared. Both decompositions capture most of the turbulent flow patterns; yet, the lower order modes show significant discrepancies between the slice-POD and 3D-POD. Therefore, in order to characterize coherent structures in turbulent flows, it is essential to perform both two- and three-dimensional decompositions. These two methods complement each other and can provide an improved interpretation of various flow features.

  9. Comparison between two and three-dimensional POD in a turbulent boundary layer using multi-plane stereoscopic PIV

    Energy Technology Data Exchange (ETDEWEB)

    Liberzon, Alex [School of Mechanical Engineering, Tel Aviv University, Ramat Aviv 69978 (Israel); Gurka, Roi [Department of Chemical Engineering, Ben Gurion University of the Negev, Beer Sheva (Israel); Hetsroni, Gad, E-mail: alexlib@eng.tau.ac.il [Faculty of Mechanical Engineering, Technion, Haifa 32000 (Israel)

    2011-12-22

    A comparison between two- and three-dimensional analyses using proper orthogonal decomposition (POD) is performed. The investigated flow field is a turbulent boundary layer in a flume. The decomposition is applied to the vorticity fields measured using a multi-plane stereoscopic particle image velocimetry (PIV) measurement system. The decomposition was applied using two methods: A) two-dimensional slices of the data that were used separately in a so-called slice-POD, and B) as a volumetric dataset that provides 3D-POD modes. Linear combination of the first three modes, energy distribution and reconstruction of snapshots are compared. Both decompositions capture most of the turbulent flow patterns; yet, the lower order modes show significant discrepancies between the slice-POD and 3D-POD. Therefore, in order to characterize coherent structures in turbulent flows, it is essential to perform both two- and three-dimensional decompositions. These two methods complement each other and can provide an improved interpretation of various flow features.

  10. Simulation of chemical potentials and phase equilibria in two- and three-dimensional square-well fluids: finite size effects.

    Science.gov (United States)

    Vörtler, Horst L; Schäfer, Katja; Smith, William R

    2008-04-17

    We study the simulation cell size dependence of chemical potential isotherms in subcritical square-well fluids by means of series of canonical ensemble Monte Carlo simulations with increasing numbers of particles, for both three-dimensional bulk systems and two-dimensional planar layers, using Widom-like particle insertion methods. By estimating the corresponding vapor/liquid coexistence densities using a Maxwell-like equal area rule for the subcritical chemical potential isotherms, we are able to study the influence of system size not only on chemical potentials but also on the coexistence properties. The chemical potential versus density isotherms show van der Waals-like loops in the subcritical vapor/liquid coexistence range that exhibit distinct finite size effects for both two- and three-dimensional fluids. Generally, in agreement with recent findings for related studies of Lennard-Jones fluids, the loops shrink with increasing number of particles. In contrast to the subcritical isotherms themselves, the equilibrium vapor/liquid densities show only a weak system size dependence and agree quantitatively with the best-known literature values for three-dimensional fluids. This allows our approach to be used to accurately predict the phase coexistence properties. Our resulting phase equilibrium results for two-dimensional square-well fluids are new. Knowledge concerning finite size effects of square-well systems is important not only for the simulation of thermodynamic properties of simple fluids, but also for the simulation of models of more complex fluids (such as aqueous or polymer fluids) involving square-well interactions.

  11. Vapour–liquid equilibria of the two- and three-dimensional monoatomic classical fluids interacting via double Yukawa potential

    Indian Academy of Sciences (India)

    Y Pathania; P K Ahluwalia

    2006-12-01

    We have carried out Monte Carlo simulations in Gibbs ensemble for two-and three-dimensional double Yukawa fluid. We have compared liquid–vapour equilibrium curve with that of Lennard-Jones, when parameters occurring in double Yukawa potential are chosen to fit Lennard-Jones potential. The results are in good agreement. The role of repulsive and attractive contributions for the potential on the liquid–vapour coexistence region as well as on critical temperature and critical density has been studied. The critical temperature is found to be more sensitive than the critical density to the variation in repulsive and attractive parts of the potential. Also, the range of the attractive interaction directly influences range of the liquid–vapour coexistence region. It has been found that smaller the values of the attractive parameter, larger is the coexistence region.

  12. Left atrial strain assessed by three-dimensional speckle tracking echocardiography predicts atrial fibrillation recurrence after catheter ablation in patients with paroxysmal atrial fibrillation.

    Science.gov (United States)

    Mochizuki, Atsushi; Yuda, Satoshi; Fujito, Takefumi; Kawamukai, Mina; Muranaka, Atsuko; Nagahara, Daigo; Shimoshige, Shinya; Hashimoto, Akiyoshi; Miura, Tetsuji

    2017-06-01

    Several studies have shown the utility of left atrial (LA) function determined by two-dimensional or three-dimensional speckle tracking echocardiography (2D- or 3D-STE) for identifying patients with paroxysmal atrial fibrillation (AF). However, whether 3D-STE is applicable for prediction of the recurrence of AF after catheter ablation (CA) remains unknown. We examined whether any 3D-STE parameters are better than 2D-STE parameters for the prediction of AF recurrence. Forty-two patients with paroxysmal AF (58 ± 10 years old, 69% male) underwent 2D- and 3D-STE within 3 days before first-time CA. The global peak LA longitudinal, circumferential, and area strains during systole (3D-GLSs, -GCSs, and -GASs, respectively) and those just before atrial contraction (3D-GLSa, -GCSa, and -GASa, respectively) were determined by 3D-STE and standard deviations of times to peaks of regional LA strains were calculated as indices of LA dyssynchrony. In 2D-STE, global LA longitudinal strains during systole and just before atrial contraction (2D-GLSs and -GLSa) were determined. During follow-up of 441 ± 221 days, 12 patients (29%) had AF recurrence. In the univariate Cox proportional hazard analysis, age [hazard ratio (HR): 1.08, p = 0.04], 3D-GCSs (HR: 0.91, p = 0.03), and 3D-GASs (HR: 0.95, p = 0.01) were predictors of AF recurrence, though associations of recurrence with 2D-STE parameters, indices of LA synchrony, and LA volume were not significant. Multivariable analysis showed that 3D-GASs was an independent predictor of AF recurrence (HR: 0.96, p = 0.048). LA strain determined by 3D-STE is a novel and better predictor of AF recurrence after CA than that determined by 2D-STE or other known predictors.

  13. Left ventricular systolic dysfunction in asymptomatic Marfan syndrome patients is related to the severity of gene mutation: insights from the novel three dimensional speckle tracking echocardiography.

    Directory of Open Access Journals (Sweden)

    Mohamed Abd El Rahman

    Full Text Available In asymptomatic Marfan syndrome (MFS patients we evaluated the relationship between the types of fibrillin-1 (FBN1 gene mutation and possible altered left ventricular (LV function as assessed by three-dimensional speckle tracking echocardiography (3D-STE.Forty-five MFS patients (mean age 24 ± 15 years and 40 age-matched healthy controls were studied. Genetic evaluation for the FBN1 gene was carried on 32 MFS patients. Gene mutation (n = 15, 47% was classified as mild when the mutation resulted in nearly normally functioning protein, while mutations resulting in abnormally function protein were considered to be severe (n = 17, 53%. All patients and controls underwent 3D-STE for evaluation of LV function by an echocardiographer blinded to the results of the genetic testing. Compared to controls, MFS patients had significantly lower 3D-STE derived LV ejection fraction (EF, 57.43 ± 7.51 vs. 62.69 ± 4.76%, p = 0.0001, global LV longitudinal strain (LS, 14.85 ± 2.89 vs. 17.90 ± 2.01%, p = 0.0001, global LV circumferential strain (CS, 13.93 ± 2.81 vs. 16.82 ± 2.17%, p = 0.0001 and global LV area strain (AS, 25.76 ± 4.43 vs. 30.51 ± 2.61%, p = 0.0001. Apart from the global LV LS all these parameters were significantly lower in patients with severe gene mutation than in those with mild mutation (p < 0.05. In the multivariate linear regression analysis only the type of mutation had a significant influence on the 3D-STE derived LVEF (p = 0.017, global CS (p = 0.005 and global AS (p = 0.03.In asymptomatic MFS patients latent LV dysfunction can be detected using 3D STE. The LV dysfunction is mainly related to the severity of gene mutation, suggesting possible primary cardiomyopathy in MFS patients.

  14. Three-dimensional transesophageal echocardiography with agitated saline injection to differentiate between atrial septal defects and echo drop-out artifacts.

    Science.gov (United States)

    Alherbish, Aws; Shanks, Miriam; Choy, Jonathan

    2014-12-01

    The diagnosis of multiple atrial septal defects is less challenging with 3-D transesophageal echocardiography. However, the common occurrence of echo drop-out (acoustic shadow) artifacts with 3-D echocardiography can make the differentiation between a second defect and an artifact challenging. Agitated saline injection with direct visualization using 3-D echocardiography can help resolve this by allowing visualization of the bubbles crossing from true defects.

  15. Comparison between the results of the two and three-dimensional numerical simulations in an aortic bifurcation model

    Science.gov (United States)

    Deplano, V.; Pelissier, R.; Rieu, R.; Bontoux, P.

    1994-01-01

    Bifurcations are vascular singularities of interest because they are the privileged sites of atherosclerosis deposits, particularly the sites corresponding to wall shear stress extrema. The purpose of this paper is to compare the two- and three-dimensional characteristics of the velocity fields, the shear stress distributions and the secondary flows in a symmetrical aortic bifurcation. The branching angle is equal to 60^{circ} and the branch-to-trunk area ratio to 0.8. The numerical simulations are performed using the FIDAP programme. Although restrictive by the hypotheses of steady flow and rigid channel, with rectangular cross-sections, this study shows the importance of the three-dimensional effects in particular as far as concerned the wall shear stress behaviours. Les bifurcations sont des singularités vasculaires présentant un intérêt particulier car elles sont le site privilégié de dépôts athéromateux ; la localisation de ces dépôts dépendant des valeurs maximum du cisaillement en paroi. L'objectif de cette étude est de comparer les caractéristiques bidimensionnels et tridimensionnels des champs de vitesse, de la distribution du cisaillement pariétal et des écoulements secondaires dans un modèle de bifurcation aortique. L'angle de bifurcation est de 60^{circ} et le rapport des sections branche fille branche mère est de 0,8. Les simulations numériques sont effectuées sur la base du logiciel FIDAP. Bien que restrictifs de part certaines hypothèses, écoulement permanent dans un modèle de bifurcation rigide avec des sections rectangulaires, ces travaux montrent l'importance des effets tridimensionnels notamment au niveau du cisaillement pariétal.

  16. Dynamic characteristic mechanism of atrial septal defect using real-time three-dimensional echocardiography and evaluation of right ventricular functions.

    Science.gov (United States)

    Sharen, Gao-Wa; Zhang, Jun; Qin, Chuan; Lv, Qing

    2017-02-01

    The dynamic characteristics of the area of the atrial septal defect (ASD) were evaluated using the technique of real-time three-dimensional echocardiography (RT 3DE), the potential factors responsible for the dynamic characteristics of the area of ASD were observed, and the overall and local volume and functions of the patients with ASD were measured. RT 3DE was performed on the 27 normal controls and 28 patients with ASD. Based on the three-dimensional data workstations, the area of ASD was measured at P wave vertex, R wave vertex, T wave starting point, and T wave terminal point and in the T-P section. The right atrial volume in the same time phase of the cardiac cycle and the motion displacement distance of the tricuspid annulus in the corresponding period were measured. The measured value of the area of ASD was analyzed. The changes in the right atrial volume and the motion displacement distance of the tricuspid annulus in the normal control group and the ASD group were compared. The right ventricular ejection fractions in the normal control group and the ASD group were compared using the RT 3DE long-axis eight-plane (LA 8-plane) method. Real-time three-dimensional volume imaging was performed in the normal control group and ASD group (n=30). The right ventricular inflow tract, outflow tract, cardiac apex muscular trabecula dilatation, end-systolic volume, overall dilatation, end-systolic volume, and appropriate local and overall ejection fractions in both two groups were measured with the four-dimensional right ventricular quantitative analysis method (4D RVQ) and compared. The overall right ventricular volume and the ejection fraction measured by the LA 8-plane method and 4D RVQ were subjected to a related analysis. Dynamic changes occurred to the area of ASD in the cardiac cycle. The rules for dynamic changes in the area of ASD and the rules for changes in the right atrial volume in the cardiac cycle were consistent. The maximum value of the changes in the

  17. Comparative two- and three-dimensional analysis of nanoparticle localization in different cell types by Raman spectroscopic imaging

    Science.gov (United States)

    Bräutigam, Katharina; Bocklitz, Thomas; Silge, Anja; Dierker, Christian; Ossig, Rainer; Schnekenburger, Jürgen; Cialla, Dana; Rösch, Petra; Popp, Jürgen

    2014-09-01

    The increasing production and application of engineered nanomaterials requires a detailed understanding of the potential toxicity of nanoparticles and their uptake in living cells and tissue. For that purpose, a highly sensitive and selective method for detecting single nonlabeled nanoparticles and nanoparticle agglomerations in cells and animal tissue is required. Here, we show that Raman microspectroscopy allows for the specific detection of TiO2 nanoparticles inside cultured NIH/3T3 fibroblasts and RAW 264.7 macrophages. The spatial position of TiO2 nanoparticles and in parallel the relative intracellular concentration and distribution of cellular constituents such as proteins or DNA residues were identified and displayed by construction of two- and three-dimensional Raman maps. The resulting Raman images reflected the significant differences in nanoparticle uptake and intracellular storage of fibroblasts and macrophages. Furthermore, TiO2 nanomaterials could be characterized and the presence of rutile- and anatase-phase TiO2 were determined inside cells. Together, the data shown here prove that Raman spectroscopic imaging is a promising technique for studying the interaction of nanomaterials with living cells and for differentiating intracellular nanoparticles from those localized on the cell membrane. The technology provides a label-free, non-destructive, material-specific analysis of whole cells with high spatial resolution, along with additional information on the current status of the material properties.

  18. Non-Boussinesq Dissolution-Driven Convection in Two- and Three-Dimensional Porous Media at Partially-Saturated Condition

    Science.gov (United States)

    Amooie, Mohammad Amin; Soltanian, Mohammad Reza; Moortgat, Joachim

    2016-11-01

    Sequestrated carbon dioxide (CO2) into saline aquifers, increases brine density through dissolution, and leads to gravitational instability and convective mixing. Traditionally, only the underlying brine-saturated subdomain is studied to avoid two-phase systems while replacing the gas cap atop with a constant, fully-saturated boundary condition. This violates the interface movement, neglects the capillary transition zone across original phases, and imposes constant density at top boundary insensitive to convective downwelling flow. Moreover, dissolution causes volume swelling, reflected as pressure build-up in absence of interface (movement), which further increases the fluid density -not captured under Boussinesq approximation. Here we accurately model the nonlinear phase behavior of brine-CO2 mixture, altered by dissolution and compressibility. We inject CO2 at a sufficiently low injection rate to maintain the single, partially-saturated phase, with no constraint on pressure and composition, so that density at top is free to change against the rate at which dissolved CO2 migrates downwards. We discover new flow regimes and present quantitative scaling relations for their temporal evolution in both two- and three-dimensional porous media.

  19. Two- and three-dimensional reformatted computed tomography imaging analysis of the lumbosacropelvic structure in degenerative anterolisthesis

    Energy Technology Data Exchange (ETDEWEB)

    Ergun, T., E-mail: tarkanergun@yahoo.co [Department of Radiology, Baskent University, Alanya Teaching and Medical Research Center, Alanya (Turkey); Sahin, M.S. [Department of Orthopaedics and Traumatology, Baskent University, Alanya Teaching and Medical Research Center, Alanya (Turkey); Lakadamyali, H. [Department of Radiology, Baskent University, Alanya Teaching and Medical Research Center, Alanya (Turkey)

    2010-11-15

    Aim: To evaluate the differences in the lumbosacropelvic structure between normal individuals and those with pseudospondylolisthesis. Materials and methods: The renal stone protocol abdominal CT images of 452 patients were retrospectively analysed. Twenty individuals who had degenerative anterolisthesis at the L5-S1 level were included in the study. Moreover, a control group of individuals was formed, similar in age and gender to the study group. A number of linear and angular lumbosacral morphological parameters were evaluated using two- and three-dimensionally reformatted CT images. The data of the two groups were compared using the t-test and Mann-Whitney U-test. Results: There was an association between spondylolisthesis and decreased thickness of the transverse process (p = 0.01), the height of the iliac crest (p = 0.028), lumbar angle (p = 0.041), sacral table angle (p = 0.033), sacral table index (p = 0.0001), sacral kyphosis (p = 0.025), sacral slope (p = 0.007), and width of the transverse process (p = 0.038), and increased transverse articular dimension of the facet joint (p = 0.003), axial angle of the facet joint (p = 0.002), sagittal angle of the facet joint (p = 0.012), S1 vertebra interfacet index (p = 0.003), the distance between the L5 vertebral transverse process and the iliac crest (p = 0.003), pelvic incidence (p = 0.016), L5 vertebra posterior angle (p = 0.001), and intersacroiliac joint angle (p = 0.024). Conclusion: The lumbosacropelvic morphology in patients with degenerative spondylolisthesis is quite different from that of normal individuals. These abnormalities should be revealed using imaging methods as they can be defining for pseudospondylolisthesis development and have important effects on therapy planning.

  20. Two and three dimensional characterization of Zucchini Yellow Mosaic Virus induced structural alterations in Cucurbita pepo L. plants.

    Science.gov (United States)

    Zellnig, Günther; Pöckl, Michael Herbert; Möstl, Stefan; Zechmann, Bernd

    2014-05-01

    Infection of plants by Zucchini Yellow Mosaic Virus (ZYMV) induces severe ultrastructural changes. The aim of this study was to investigate ultrastructural changes during ZYMV-infection in Cucurbita pepo L. plants on the two and three dimensional (2D and 3D) level and to correlate these changes with the spread of ZYMV throughout the plant by transmission electron microscopy (TEM) and image analysis. This study revealed that after inoculation of the cotyledons ZYMV moved into roots [3 days post inoculation (dpi)], then moved upwards into the stem and apical meristem (5 dpi), then into the first true leaf (7 dpi) and could finally be found in all plant parts (9 dpi). ZYMV-infected cells contained viral inclusion bodies in the form of cylindrical inclusions (CIs). These CIs occurred in four different forms throughout the cytosol of roots and leaves: scrolls and pinwheels when cut transversely and long tubular structures and bundles of filaments when cut longitudinally. 3D reconstruction of ZYMV-infected cells containing scrolls revealed that they form long tubes throughout the cytosol. The majority has a preferred orientation and an average length and width of 3 μm and 120 nm, respectively. Image analysis revealed an increased size of cells and vacuoles (107% and 447%, respectively) in younger ZYMV-infected leaves leading to a similar ratio of cytoplasm to vacuole (about 1:1) in older and younger ZYMV-infected leaves which indicates advanced cell growth in younger tissues. The collected data advances the current knowledge about ZYMV-induced ultrastructural changes in Cucurbita pepo. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  1. Coherent structures and flow topology of transitional separated-reattached flow over two and three dimensional geometrical shapes

    Science.gov (United States)

    Diabil, Hayder Azeez; Li, Xin Kai; Abdalla, Ibrahim Elrayah

    2017-09-01

    Large-scale organized motions (commonly referred to coherent structures) and flow topology of a transitional separated-reattached flow have been visualised and investigated using flow visualisation techniques. Two geometrical shapes including two-dimensional flat plate with rectangular leading edge and three-dimensional square cylinder are chosen to shed a light on the flow topology and present coherent structures of the flow over these shapes. For both geometries and in the early stage of the transition, two-dimensional Kelvin-Helmholtz rolls are formed downstream of the leading edge. They are observed to be twisting around the square cylinder while they stay flat in the case of the two-dimensional flat plate. For both geometrical shapes, the two-dimensional Kelvin-Helmholtz rolls move downstream of the leading edge and they are subjected to distortion to form three-dimensional hairpin structures. The flow topology in the flat plate is different from that in the square cylinder. For the flat plate, there is a merging process by a pairing of the Kelvin-Helmholtz rolls to form a large structure that breaks down directly into many hairpin structures. For the squire cylinder case, the Kelvin-Helmholtz roll evolves topologically to form a hairpin structure. In the squire cylinder case, the reattachment length is much shorter and a forming of the three-dimensional structures is closer to the leading edge than that in the flat plate case.

  2. Quality of Oocytes Derived from Vitrified Ovarian Follicles Cultured in Two- and Three-Dimensional Culture System in the Presence and Absence of Kit Ligand.

    Science.gov (United States)

    Abdi, Shabnam; Salehnia, Mojdeh; Hosseinkhani, Saman

    2016-08-01

    The aim of this study was to evaluate the effects of Kit Ligand (KL) on the growth of vitrified follicle, oocyte quality, and embryo development in two- and three-dimensional culture systems. Vitrified and nonvitrified mouse whole ovaries were cultured for 1 week, then their isolated preantral follicles were cultured for 12 days in two- or three-dimensional culture systems in the presence and absence of KL. The growth and diameter of follicles, maturation of oocytes, and hormonal level were assessed. Finally, embryo developmental rate and oocytes reactive oxygen species (ROS) levels, adenosine triphosphate (ATP) content, and distribution of mitochondria were examined. The results showed the maturation and survival rates and steroidogenesis of follicles were significantly higher not only in the three-dimensional culture system but also in the presence of KL (p culture in two- and three-dimensional culture systems appeared to significantly increase follicular function and development. The ovarian vitrification had no harmful effect on the steroidogenesis, growth, and maturation of follicles.

  3. Two- and three-dimensional ultrasound imaging to facilitate detection and targeting of taut bands in myofascial pain syndrome.

    Science.gov (United States)

    Shankar, Hariharan; Reddy, Sapna

    2012-07-01

    Ultrasound imaging has gained acceptance in pain management interventions. Features of myofascial pain syndrome have been explored using ultrasound imaging and elastography. There is a paucity of reports showing the benefit clinically. This report provides three-dimensional features of taut bands and highlights the advantages of using two-dimensional ultrasound imaging to improve targeting of taut bands in deeper locations. Fifty-eight-year-old man with pain and decreased range of motion of the right shoulder was referred for further management of pain above the scapula after having failed conservative management for myofascial pain syndrome. Three-dimensional ultrasound images provided evidence of aberrancy in the architecture of the muscle fascicles around the taut bands compared to the adjacent normal muscle tissue during serial sectioning of the accrued image. On two-dimensional ultrasound imaging over the palpated taut band, areas of hyperechogenicity were visualized in the trapezius and supraspinatus muscles. Subsequently, the patient received ultrasound-guided real-time lidocaine injections to the trigger points with successful resolution of symptoms. This is a successful demonstration of utility of ultrasound imaging of taut bands in the management of myofascial pain syndrome. Utility of this imaging modality in myofascial pain syndrome requires further clinical validation. Wiley Periodicals, Inc.

  4. Automated two- and three-dimensional, fine-resolution radar imaging of rigid targets with arbitrary unknown motion

    Science.gov (United States)

    Stuff, Mark A.; Sullivan, Richard C., Jr.; Thelen, Brian J.; Werness, Susan A.

    1994-06-01

    An automated system for the SAR/ISAR imaging of rigid bodies which are undergoing arbitrarily complicated unknown motions is being developed. This system determines, from only the radar data, all observable parameters of motion, on a pulse by pulse basis. The approach makes it possible to: (1) exploit any type of relative motion: translational, rotational, two dimensional, three dimensional, deterministic, or stochastic; no prior parametric assumptions on the functional form of the motion are required; (2) require only the radar data; no ancillary motion measurement system on either the radar platform or on the target is required; (3) automatically provide all the motion information needed to form correctly scaled images, without cross range scale ambiguities; (4) make full use of all the radar data; no signals returning from a target are discarded; and (5) require a known computation time, which is not signal dependent, as all iterative processes used have known, guaranteed convergence rates.

  5. Pair correlation functions of two- and three-dimensional hard-core fluids confined into narrow pores: exact results from transfer-matrix method.

    Science.gov (United States)

    Gurin, Péter; Varga, Szabolcs

    2013-12-28

    The effect of confinement is studied on the local structure of two- and three-dimensional hard-core fluids. The hard disks are confined between two parallel lines, while the hard spheres are in a cylindrical hard pore. In both cases only nearest neighbour interactions are allowed between the particles. The vertical and longitudinal pair correlation functions are determined by means of the exact transfer-matrix method. The vertical pair correlation function indicates that the wall induced packing constraint gives rise to a zigzag (up-down sequence) shaped close packing structure in both two- and three-dimensional systems. The longitudinal pair correlation function shows that both systems transform continuously from a one-dimensional gas-like behaviour to a zigzag solid-like structure with increasing density.

  6. Comparison of vacuum glazing thermal performance predicted using two- and three-dimensional models and their experimental validation

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Yueping; Hyde, Trevor; Hewitt, Neil [Centre for Sustainable Technologies, School of the Built Environment, University of Ulster, Newtownabbey, BT37 0QB Northern Ireland (United Kingdom); Eames, Philip C. [Centre for Research in Renewable Energy Science and Technology, University of Loughborough (United Kingdom); Norton, Brian [Dublin Energy Lab, Dublin Institute of Technology, Aungier Street, Dublin 2 (Ireland)

    2009-09-15

    Thermal performance of vacuum glazing predicted by using two-dimensional (2-D) finite element and three-dimensional (3-D) finite volume models are presented. In the 2-D model, the vacuum space, including the pillar arrays, was represented by a material whose effective thermal conductivity was determined from the specified vacuum space width, the heat conduction through the pillar array and the calculated radiation heat transfer between the two interior glass surfaces within the vacuum gap. In the 3-D model, the support pillar array was incorporated and modelled within the glazing unit directly. The predicted difference in overall heat transfer coefficients between the two models for the vacuum window simulated was less than 3%. A guarded hot box calorimeter was used to determine the experimental thermal performance of vacuum glazing. The experimentally determined overall heat transfer coefficient and temperature profiles along the central line of the vacuum glazing are in very good agreement with the predictions made using the 2-D and 3-D models. (author)

  7. A Comparison of Two- and Three-dimensional Neutrino-hydrodynamics simulations of Core-collapse Supernovae

    CERN Document Server

    Takiwaki, Tomoya; Suwa, Yudai

    2013-01-01

    We present numerical results on two- (2D) and three-dimensional (3D) hydrodynamic core-collapse simulations of an 11.2$M_\\odot$ star. By changing numerical resolutions and seed perturbations systematically, we study how the postbounce dynamics is different in 2D and 3D. The calculations were performed with an energy-dependent treatment of the neutrino transport based on the isotropic diffusion source approximation scheme, which we have updated to achieve a very high computational efficiency. All the computed models in this work including nine 3D models and fifteen 2D models exhibit the revival of the stalled bounce shock, leading to the possibility of explosion. All of them are driven by the neutrino-heating mechanism, which is fostered by neutrino-driven convection and the standing-accretion-shock instability (SASI). Reflecting the stochastic nature of multi-dimensional (multi-D) neutrino-driven explosions, the blast morphology changes from models to models. However, we find that the final fate of the multi-...

  8. Two and three-dimensional morphometric analysis of trabecular bone using X-ray microtomography (μCT)

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Alessandro Marcio Hakme da; Silva, Orivaldo Lopes da; Silva Junior, Nelson Ferreira da, E-mail: alhakme@sc.usp.br [Universidade de Sao Paulo (EESC/FMRP/IQSC/USP), Sao Carlos, SP (Brazil); Alves, Jose Marcos [Universidade de Sao Paulo (USP), Sao Carlos, SP (Brazil). Escola de Engenharia. Departamento de Engenharia Eletrica e Computacao

    2014-07-01

    Introduction: trabecular bones have a porous microstructure and can be modeled as linear elastic solids, heterogeneous and anisotropic. In the literature, few investigations have compared the two- dimensional (2D) and three-dimensional (3D) morphometric analyses of cancellous bone. Methods: In this investigation eighteen cylindrical samples of cancellous bone (10 mm of diameter and 20 mm of height) were obtained from six bovine head femurs, with similar values for the weight and age, of the same race and gender. The samples were harvested and freeze at - 20 °C before carrying out the micro CT analysis. The CT-Analyzer software was used to measure in three directions (superior-inferior, lateral-medial and anterior-posterior) parameters such as trabecular thickness, trabecular separation, trabecular number and the eigenvalues of the fabric tensor (M). Results: the Comparison of 2D and 3D analyses for the parameters: 2D (plate model) trabecular thickness, trabecular separation and trabecular number were statistically different (p = 0) showing that measurements are not similar to the 3D ones. However, 2D (rod model) trabecular thickness and 3D trabecular thickness measurements presented no significant difference (p = 0.26). The eigenvalues show that the bovine trabecular microstructure has a tendency to transversally isotropic symmetry. Discussion: The method proved to be quite interesting for the characterization of the bone structure through 3D measurements of trabecular bone morphometric parameters in the three possible directions of loading. The results show that x-ray microtomography (μCT) is a technique of great potential for characterization and generating bone quality parameters for the diagnosis of bone metabolism diseases. (author)

  9. Repeat prostate biopsy accuracy: simulator-based comparison of two- and three-dimensional transrectal US modalities.

    Science.gov (United States)

    Cool, Derek W; Connolly, Michael J; Sherebrin, Shi; Eagleson, Roy; Izawa, Jonathan I; Amann, Justin; Romagnoli, Cesare; Romano, Walter M; Fenster, Aaron

    2010-02-01

    To compare the accuracy of biopsy with two-dimensional (2D) transrectal ultrasonography (US) with that of biopsy with conventional three-dimensional (3D) transrectal US and biopsy with guided 3D transrectal US in the guidance of repeat prostate biopsy procedures in a prostate biopsy simulator. The institutional review board approved this retrospective study. Five residents and five experts performed repeat biopsies with a biopsy simulator that contained the transrectal US prostate images of 10 patients who had undergone biopsy. Simulated repeat biopsies were performed with 2D transrectal US, conventional 3D transrectal US, and guided 3D transrectal US (an extension of 3D transrectal US that enables active display of biopsy targets). The modalities were compared on the basis of time per biopsy and how accurately simulated repeat biopsies could be guided to specific targets. The probability for successful biopsy of a repeat target was calculated for each modality. Guided 3D transrectal US was significantly (P < .01) more accurate for simulated biopsy of repeat targets than was 2D or 3D transrectal US, with a biopsy accuracy of 0.86 mm +/- 0.47 (standard deviation), 3.68 mm +/- 2.60, and 3.60 mm +/- 2.57, respectively. Experts had a 70% probability of sampling a prior biopsy target volume of 0.5 cm(3) with 2D transrectal US; however, the probability approached 100% with guided 3D transrectal US. Biopsy accuracy was not significantly different between experts and residents for any modality; however, experts were significantly (P < .05) faster than residents with each modality. Repeat biopsy of the prostate with 2D transrectal US has limited accuracy. Compared with 2D transrectal US, the biopsy accuracy of both experts and residents improved with guided 3D transrectal US but did not improve with conventional 3D transrectal US.

  10. MicroRNA expression in the vildagliptin-treated two- and three-dimensional HepG2 cells.

    Science.gov (United States)

    Yamashita, Yasunari; Asakura, Mitsutoshi; Mitsugi, Ryo; Fujii, Hideaki; Nagai, Kenichiro; Atsuda, Koichiro; Itoh, Tomoo; Fujiwara, Ryoichi

    2016-06-01

    Vildagliptin is an inhibitor of dipeptidyl peptidase-4 that is used for the treatment of type 2 diabetes mellitus. While vildagliptin can induce hepatic dysfunction in humans, the molecular mechanism has not been determined yet. Recent studies indicated that certain types of microRNA (miRNA) were linking to the development of drug-induced hepatotoxicity. In the present study, therefore, we identified hepatic miRNAs that were highly induced or reduced by the vildagliptin treatment in mice. MiR-222 and miR-877, toxicity-associated miRNAs, were induced 31- and 53-fold, respectively, by vildagliptin in the liver. While a number of miRNAs were significantly regulated by the orally treated vildagliptin in vivo, such regulation was not observed in the vildagliptin-treated HepG2 cells. In addition to the regular two-dimensional (2D) culture, we carried out the three-dimensional (3D) culturing of HepG2 cells. In the 3D-HepG2 cells, a significant reduction of miR-222 was observed compared to the expression level in 2D-HepG2 cells. A slight induction of miR-222 by vildagliptin was observed in the 3D-HepG2 cells, although miR-877 was not induced by vildagliptin even in the 3D-HepG2 cells. Further investigations are needed to overcome the discrepancy in the responsiveness of the miRNA expressions to vildagliptin between in vivo and in vitro. Copyright © 2016 The Japanese Society for the Study of Xenobiotics. Published by Elsevier Ltd. All rights reserved.

  11. Three-dimensional mapping of mechanical activation patterns, contractile dyssynchrony and dyscoordination by two-dimensional strain echocardiography: Rationale and design of a novel software toolbox

    Directory of Open Access Journals (Sweden)

    Cramer Maarten J

    2008-05-01

    Full Text Available Abstract Background Dyssynchrony of myocardial deformation is usually described in terms of variability only (e.g. standard deviations SD's. A description in terms of the spatio-temporal distribution pattern (vector-analysis of dyssynchrony or by indices estimating its impact by expressing dyscoordination of shortening in relation to the global ventricular shortening may be preferential. Strain echocardiography by speckle tracking is a new non-invasive, albeit 2-D imaging modality to study myocardial deformation. Methods A post-processing toolbox was designed to incorporate local, speckle tracking-derived deformation data into a 36 segment 3-D model of the left ventricle. Global left ventricular shortening, standard deviations and vectors of timing of shortening were calculated. The impact of dyssynchrony was estimated by comparing the end-systolic values with either early peak values only (early shortening reserve ESR or with all peak values (virtual shortening reserve VSR, and by the internal strain fraction (ISF expressing dyscoordination as the fraction of deformation lost internally due to simultaneous shortening and stretching. These dyssynchrony parameters were compared in 8 volunteers (NL, 8 patients with Wolff-Parkinson-White syndrome (WPW, and 7 patients before (LBBB and after cardiac resynchronization therapy (CRT. Results Dyssynchrony indices merely based on variability failed to detect differences between WPW and NL and failed to demonstrate the effect of CRT. Only the 3-D vector of onset of shortening could distinguish WPW from NL, while at peak shortening and by VSR, ESR and ISF no differences were found. All tested dyssynchrony parameters yielded higher values in LBBB compared to both NL and WPW. CRT reduced the spatial divergence of shortening (both vector magnitude and direction, and improved global ventricular shortening along with reductions in ESR and dyscoordination of shortening expressed by ISF. Conclusion Incorporation

  12. Two- and three-dimensional magnetic reconnection observed in the Eulerian-Lagrangian analysis of magnetohydrodynamics equations.

    Science.gov (United States)

    Ohkitani, K; Constantin, P

    2008-12-01

    We study reconnection phenomena in magnetohydrodynamics on the basis of a magnetohydrodynamic version of the Eulerian-Lagrangian analysis. We find that the methods are useful in capturing time scales associated with magnetic reconnection both in two and three dimensions. Visualizations show that the determinants of the Jacobian determinants of the diffusive labels are small where active reconnection takes place. The resetting of the diffusive labels extracts a short time scale during reconnection.

  13. Left ventricular layer function in hypertension assessed by myocardial strain rate using novel one-beat real-time three-dimensional speckle tracking echocardiography with high volume rates.

    Science.gov (United States)

    Saeki, Maki; Sato, Noriaki; Kawasaki, Masanori; Tanaka, Ryuhei; Nagaya, Maki; Watanabe, Takatomo; Ono, Koji; Noda, Toshiyuki; Zile, Michael R; Minatoguchi, Shinya

    2015-08-01

    We recently developed novel software to measure phasic strain rate (SR) using automated one-beat real-time three-dimensional speckle tracking echocardiography (3D-STE) with high volume rates. We tested the hypothesis that left ventricular (LV) systolic function and relaxation analyzed by SR with the novel 3D-STE in hypertension (HTN) with hypertrophy may be impaired in the endocardium before there is LV systolic dysfunction. We measured LV longitudinal, radial and circumferential SR in patients with HTN (n=80, 69±7 years) and age-matched normotensive controls (n= 60, 69±10 years) using 3D-STE. HTN patients were divided into four groups according to LV geometry: normal, concentric remodeling, concentric hypertrophy and eccentric hypertrophy. We measured SR during systole as an index of systolic function, SR during isovolumic relaxation (IVR) as an index of relaxation and E/e' as an index of filling pressure. Endocardial SR during systole in HTN with concentric and eccentric hypertrophy decreased compared with that in controls despite no reduction in ejection fraction or epicardial SR. Endocardial radial SR during IVR decreased even in normal geometry, and it was further reduced in concentric remodeling and hypertrophy despite no reduction in epicardial SR. LV phasic SR assessed by 3D-STE with high volume rates is a useful index to detect early decreases in LV systolic function and to predict subclinical LV layer dysfunction in patients with HTN.

  14. Competing magnetic orders and spin liquids in two- and three-dimensional kagome systems: Pseudofermion functional renormalization group perspective

    Science.gov (United States)

    Buessen, Finn Lasse; Trebst, Simon

    2016-12-01

    Quantum magnets on kagome lattice geometries in two and three spatial dimensions are archetypal examples of spin systems in which geometric frustration inhibits conventional magnetic ordering and instead benefits the emergence of long-range entangled spin liquids at low temperature. Here we employ a recently developed pseudofermion functional renormalization group (pf-FRG) approach to study the low-temperature quantum magnetism of kagome and hyperkagome spin systems with exchange interactions beyond the nearest-neighbor coupling. We find that next-nearest-neighbor couplings stabilize a variety of magnetic orders as well as induce additional spin liquid regimes, giving rise to rather rich phase diagrams, which we characterize in detail. On a technical level, we find that the pf-FRG approach is in excellent quantitative agreement with high-temperature series expansions over their range of validity and it exhibits a systematic finite-size convergence in the temperature regime below. We discuss notable advantages and some current limitations of the pf-FRG approach in the ongoing search for unconventional forms of quantum magnetism.

  15. Classical many-body problems amenable to exact treatments (solvable and/or integrable and/or linearizable...) in one-, two- and three-dimensional space

    CERN Document Server

    Calogero, Francesco

    2001-01-01

    This book focuses on exactly treatable classical (i.e. non-quantal non-relativistic) many-body problems, as described by Newton's equation of motion for mutually interacting point particles. Most of the material is based on the author's research and is published here for the first time in book form. One of the main novelties is the treatment of problems in two- and three-dimensional space. Many related techniques are presented, e.g. the theory of generalized Lagrangian-type interpolation in higher-dimensional spaces. This book is written for students as well as for researchers; it works out detailed examples before going on to treat more general cases. Many results are presented via exercises, with clear hints pointing to their solutions.

  16. Two- and Three-Dimensional Multi-Physics Simulations of Core Collapse Supernovae: A Brief Status Report and Summary of Results from the "Oak Ridge" Group

    CERN Document Server

    Mezzacappa, Anthony; Lentz, Eric J; Hix, W Raphael; Messer, O E Bronson; Harris, J Austin; Lingerfelt, Eric J; Endeve, Eirik; Yakunin, Konstantin N; Blondin, John M; Marronetti, Pedro

    2014-01-01

    We summarize the results of core collapse supernova theory from one-, two-, and three-dimensional models and provide a snapshot of the field at this time. We also present results from the "Oak Ridge" group in this context. Studies in both one and two spatial dimensions define the necessary} physics that must be included in core collapse supernova models: a general relativistic treatment of gravity (at least an approximate one), spectral neutrino transport, including relativistic effects such as gravitational redshift, and a complete set of neutrino weak interactions that includes state-of-the-art electron capture on nuclei and energy-exchanging scattering on electrons and nucleons. Whether or not the necessarily approximate treatment of this physics in current models that include it is sufficient remains to be determined in the context of future models that remove the approximations. We summarize the results of the Oak Ridge group's two-dimensional supernova models. In particular, we demonstrate that robust n...

  17. A numerical study of two- and three-dimensional detonation dynamics of pulse detonation engine by the CE/SE method

    Institute of Scientific and Technical Information of China (English)

    Chunsheng Weng; Jay P. Gore

    2005-01-01

    In this paper, the CE/SE method is developed to simulate the two- and three-dimensional flow-field of Pulse Detonation Engine (PDE). The conservation equations with stiff source terms for chemical reaction are solved in two steps. The detailed analysis of computational results of a PDE with a single detonation tube and a PDE with five detonation tubes are given in this paper. Complex wave systems are observed inside and outside a PDE. For a PDE with 5 detonation tubes, there is a big bow shock produced from a number of little shocks near the open ends of tubes. A lot of vortexes interact with shocks and a large expansion wave propagates forward and backward with respect to the PDE in a semi-oval shape.

  18. Eddy-current analysis of isolated permanent-magnet drives using two- and three-dimensional finite-element methods (abstract)

    Science.gov (United States)

    Ferreira, C. A.

    1990-05-01

    Present drive systems which rely on mechanical devices for torque transmission have some negative features: the driven component cannot be isolated from the drive motor, rotating seals have inherent leakage and friction problems, and mechanical failures often occur due to torque overloads. Magnetic couplings are especially well suited for use in isolated-drive systems. This is often the case in military and aerospace applications where pumps and compressors are vital parts of the thermal and fuel operating systems. The application of permanent-magnet couplings in isolated drives requires accurate calculation of the eddy-current losses induced on the hermetic vessel. This is because the losses along with the required output torque dictate the size and efficiency of the permanent-magnet coupling. The vessel isolates the drive member from the driven member of the turbocompressor. The paper will show the formulation of the computational method based on the Poynting-vector theorem and the concept of motional electric field intensity. The eddy-current losses are calculated using two- and three-dimensional magnetostatic finite-element (FE) analysis. A comparison of the results obtained by two- and three-dimensional FE analysis is made. The results of the analysis will be compared to test data for verification. The test-facility setup and procedure will also be described. This state-of-the-art technique for computation of eddy-current losses has several advantages over conventional analysis methods: the nonlinearities of the magnetic circuit are taken into account, magnetic field fringing and end-leakage effects are not neglected, and the method does not rely on the use of empirical factors. The significant benefits of this approach are that trial-and-error experimental design approaches are eliminated and test data provide validation of analytical results.

  19. Evaluating clinic significance of mitral valvular prolapse by dynamic three-dimensional reconstruction of echocardiography%动态三维超声重建评价二尖瓣脱垂的临床意义

    Institute of Scientific and Technical Information of China (English)

    郭薇; 陈斌; 卢荔红; 俞玲; 陈德伟

    2001-01-01

    Objective The significance of dynamic three-dimensional reconstruction of echocardiography(3DRE) for mitral valvular prolapse(MVP) was evaluated.Methods Twenty patients with MVP including 13 men and 7 women (aged 13~56 years) were studied by dynamic 3DRE.The prolapsed mitral valves and their tendinous chordae were viewed. The ranges of valvular prolapse were measured.Results The surfaces of the prolapsed mitral valves showed rough and accompanied with abnormal tendinous chordae , and their bodies projected into left atrium during systole. The degree of valvular regurgitation was not related with the range of prolapse and was related with the severity of tendinous chorda injury.Conclusions The statns of prolapse could be showed objectively by dynamic 3DRE of MVP, which has obvious clinic significance.%目的评价动态三维超声重建对二尖瓣脱垂的意义。方法应用动态三维超声重建对20例二尖瓣脱垂患者进行研究,其中男性13例,女性7例,年龄15~56岁。观察脱垂的二尖瓣瓣膜与腱索,测量瓣膜脱垂的范围。结果收缩期脱垂的二尖瓣表面粗糙并向左房膨出,可伴有腱索异常。瓣膜反流的程度与脱垂范围的大小无正相关,与腱索损害的严重性有关。结论应用动态三维超声重建二尖瓣脱垂能较客观地反映脱垂的情况,有明显的临床意义。

  20. Aorto-left ventricular tunnel complicated with infective endocarditis: diagnosed by transthoracic two-dimensional and three-dimensional echocardiography%经胸二维和三维超声心动图诊断主动脉-左心室通道合并感染性心内膜炎一例

    Institute of Scientific and Technical Information of China (English)

    程蕾蕾; 赵维鹏; 潘翠珍; 丁文军; 王春生; 舒先红

    2011-01-01

    IntroductionAorto-left ventricular tunnel(ALVT)is an extrenle rare(0.001%)congenital para-valvular conmmnication between aorta and the left ventricle.It was first reported by Edwards and his colleagues in 1961[ 1].Only about 100 cases have been reported until now.We re port Out"first ease of ALVT with infective endocarditis demonstrated by two-dimensional and three-dimensional echocardiography and confirmed by surgery.%@@ IntroductionAorto-left ventricular tunnel ( ALVT) is an extreme rare (0.001% ) congenital para-valvular communication between aorta and the left ventricle.It was first reported by Edwards and his colleagues in 1961[1].Only about 100 cases have been reported until now.We report our first case of ALVT with infective endocarditis demonstrated by two-dimensional and three-dimensional echocardiography and confirmed by surgery.

  1. Three-dimensional mixed-wet random pore-scale network modeling of two- and three-phase flow in porous media. I. Model description.

    Science.gov (United States)

    Piri, Mohammad; Blunt, Martin J

    2005-02-01

    We present a three-dimensional network model to simulate two- and three-phase capillary dominated processes at the pore level. The displacement mechanisms incorporated in the model are based on the physics of multiphase flow observed in micromodel experiments. All the important features of immiscible fluid flow at the pore scale, such as wetting layers, spreading layers of the intermediate-wet phase, hysteresis, and wettability alteration are implemented in the model. Wettability alteration allows any values for the advancing and receding oil-water, gas-water, and gas-oil contact angles to be assigned. Multiple phases can be present in each pore or throat (element), in wetting and spreading layers, as well as occupying the center of the pore space. In all, some 30 different generic fluid configurations for two- and three-phase flow are analyzed. Double displacement and layer formation are implemented as well as direct two-phase displacement and layer collapse events. Every element has a circular, square, or triangular cross section. A random network that represents the pore space in Berea sandstone is used in this study. The model computes relative permeabilities, saturation paths, and capillary pressures for any displacement sequence. A methodology to track a given three-phase saturation path is presented that enables us to compare predicted and measured relative permeabilities on a point-by-point basis. A robust displacement-based clustering algorithm is also presented.

  2. Three dimensional strained semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Voss, Lars; Conway, Adam; Nikolic, Rebecca J.; Leao, Cedric Rocha; Shao, Qinghui

    2016-11-08

    In one embodiment, an apparatus includes a three dimensional structure comprising a semiconductor material, and at least one thin film in contact with at least one exterior surface of the three dimensional structure for inducing a strain in the structure, the thin film being characterized as providing at least one of: an induced strain of at least 0.05%, and an induced strain in at least 5% of a volume of the three dimensional structure. In another embodiment, a method includes forming a three dimensional structure comprising a semiconductor material, and depositing at least one thin film on at least one surface of the three dimensional structure for inducing a strain in the structure, the thin film being characterized as providing at least one of: an induced strain of at least 0.05%, and an induced strain in at least 5% of a volume of the structure.

  3. Melanocyte migration is influenced by E-cadherin-dependent adhesion of keratinocytes in both two- and three-dimensional in vitro wound models.

    Science.gov (United States)

    Keswell, Dheshnie; Kidson, Susan H; Davids, Lester M

    2015-02-01

    During wound healing, melanocytes are required to migrate into the wounded area that is still in the process of re-construction. The role and behaviour of melanocytes during this process is poorly understood, that is, whether melanocyte migration into the wound is keratinocyte-dependent or not. This paper attempts, through the use of both two- and three-dimensional in vitro models, to understand the role and behaviour of melanocytes during the process of wound healing. In addition, it sheds light on whether keratinocytes influence/contribute toward melanocyte migration and ultimately wound healing. Scratch assays were performed to analyse migration and Western blot analyses measured cellular E-cadherin expression. Immunohistochemistry was used to analyse the in vivo 3D wound healing effect. Scratch assays performed on co-cultures of melanocytes and keratinocytes demonstrated that melanocytes actively migrated, with the use of their dendrites, into the scratch ahead of the proliferating keratinocyte sheet. Migration of the melanocyte into the wound bed was accompanied by loss of attachment to keratinocytes at the wound front with concomitant downregulation of E-cadherin expression as observed through immunocytochemistry. This result suggests that, in vitro, melanocyte migration occurs independently of keratinocytes but that the migration is influenced by keratinocyte E-cadherin expression. We now demonstrate that melanocyte migration during re-pigmentation is an active process, and suggest that targeting of mechanisms involved in active melanocyte migration (e.g. the melanocyte dendrite) may enhance the re-pigmentation process. © 2014 International Federation for Cell Biology.

  4. Two and three-dimensional computed tomography for the classification and management of distal humeral fractures - Evaluation of reliability and diagnostic accuracy

    NARCIS (Netherlands)

    J. Doornberg; A. Lindenhovius; P. Kloen; C.N. van Dijk; D. Zurakowski; D. Ring

    2006-01-01

    Background: Complex fractures of the distal part of the humerus can be difficult to characterize on plain radiographs and two-dimensional computed tomography scans. We tested the hypothesis that three-dimensional reconstructions of computed tomography scans improve the reliability and accuracy of fr

  5. Real - time three - dimensional Echocardiography Evaluation of Left Ventricular Wall Systolic Function and Exercise Echocardiography Correlation%实时三维超声心动图评价左心室下壁节段收缩功能与运动心电图的相关性研究

    Institute of Scientific and Technical Information of China (English)

    时均贵; 艾阳平; 杨海燕

    2011-01-01

    To by evaluate the left ventricular wall segments of coronary heart disease with exercise electrocardiography (ECG) test function and the correlation. Real - time three - dimensional echocardiography were measured in 30 healthy persons and 30 patients with coronary heart disease of left ventricular wall segments segments and stroke volume (regional stroke volume, r5V), end diastolic volume (rEDV), radio segment rate (rEF), all subjects were exercised treadmill test examination.60 cases obtained real - time three - dimensional images with clear endocardial order and 17 segmental volume - time curve; two groups of 17 segments rSV, rEDV, rPEF measured values were statistically significant P < 0.05), coronary heart disease in patients with segmental function and exercise stress test positive ST segment changes were highly correlated (P<0.05). The coronary heart disease patients with normal left ventricular systolic function are different, the quantitative real - time three - dimensional echocardiography evaluation of left ventricular systolic dysfunction and exercise treadmill test is positive for the detection of coronary artery disease highly correlated.%应用实时三维超声心动图技术评价冠心病患者左心室壁节段功能及其与运动心电图试验的相关性.应用实时三维超声心动图分别测量30例健康者和30冠心痛患者的左室壁节段节段每搏量(regional stroke volume,rSV)、舒张末容积(rEDV)、节段射率(rPEF),对所有受测者进行运动平板试验检查.60例受测者均获得了具有清晰内膜边界的实时三维图像和17节段容积-时间曲线;两组间17节段rSV、rEDV、rEF测值间差异有统计学意义(P<0.05),冠心病患者的节段功能与运动平板试验阳性的ST段改变高度相关(P<0.05).冠心病患者与正常人左室壁节段收缩功能存在差异,实时三维超声心动图定量评价左室壁节段收缩功能异常与运动平板试验阳性对冠心病的检测高度相关.

  6. GRID2D/3D: A computer program for generating grid systems in complex-shaped two- and three-dimensional spatial domains. Part 1: Theory and method

    Science.gov (United States)

    Shih, T. I.-P.; Bailey, R. T.; Nguyen, H. L.; Roelke, R. J.

    1990-01-01

    An efficient computer program, called GRID2D/3D was developed to generate single and composite grid systems within geometrically complex two- and three-dimensional (2- and 3-D) spatial domains that can deform with time. GRID2D/3D generates single grid systems by using algebraic grid generation methods based on transfinite interpolation in which the distribution of grid points within the spatial domain is controlled by stretching functions. All single grid systems generated by GRID2D/3D can have grid lines that are continuous and differentiable everywhere up to the second-order. Also, grid lines can intersect boundaries of the spatial domain orthogonally. GRID2D/3D generates composite grid systems by patching together two or more single grid systems. The patching can be discontinuous or continuous. For continuous composite grid systems, the grid lines are continuous and differentiable everywhere up to the second-order except at interfaces where different single grid systems meet. At interfaces where different single grid systems meet, the grid lines are only differentiable up to the first-order. For 2-D spatial domains, the boundary curves are described by using either cubic or tension spline interpolation. For 3-D spatial domains, the boundary surfaces are described by using either linear Coon's interpolation, bi-hyperbolic spline interpolation, or a new technique referred to as 3-D bi-directional Hermite interpolation. Since grid systems generated by algebraic methods can have grid lines that overlap one another, GRID2D/3D contains a graphics package for evaluating the grid systems generated. With the graphics package, the user can generate grid systems in an interactive manner with the grid generation part of GRID2D/3D. GRID2D/3D is written in FORTRAN 77 and can be run on any IBM PC, XT, or AT compatible computer. In order to use GRID2D/3D on workstations or mainframe computers, some minor modifications must be made in the graphics part of the program; no

  7. Three-dimensional echocardiographic assessment of atrial septal defects

    Directory of Open Access Journals (Sweden)

    Charles German

    2015-01-01

    Full Text Available Echocardiography provides a useful tool in the diagnosis of many congenital heart diseases, including atrial septal defects, and aids in further delineating treatment options. Although two-dimensional echocardiography has been the standard of care in this regard, technological advancements have made three-dimensional echocardiography possible, and the images obtained in this new imaging modality are able to accurately portray the morphology, location, dimensions, and dynamic changes of defects and many other heart structures during the cardiac cycle.

  8. 术中三维超声检测二尖瓣成形前后瓣环空间构型的变化%The annulus configuration changes after mitral repair measured by three dimensional echocardiography

    Institute of Scientific and Technical Information of China (English)

    张海波; 孟旭; 郭勇; 何怡华; 韩杰; 李岩

    2014-01-01

    目的 观察术中三维超声技术检测二尖瓣成形术前后二尖瓣环空间构型的变化.方法 选择单纯二尖瓣退行性变导致重度瓣膜反流患者36例,无其他合并心脏疾病.入院后体表二维超声检测,在手术室术前经食管三维超声检测复查二尖瓣反流部位和程度,以及二尖瓣瓣环空间构型,包括二尖瓣环环径、横径、纵径、瓣环高度、前叶合后叶非平面夹角等,并初步确立手术成形方法.术后同样进行三维食管超声检测相同内容.结果 36例患者术前体表二维超声检查与术中发现完全吻合者26例(72.2%),部分吻合6例(16.7%),差距较大4例(1 1.1%).在整个心动周期中二尖瓣环持续呈“马鞍形”,于前外侧交界、后内侧交界处较低,于前瓣环、后瓣环较高.手术前后瓣环周长、瓣环横径和瓣环纵径分别为(12.4±1.4)、(7.5±0.5)cm;(34.8±2.7)、(21.8 ±1.8)mm;(34.9±3.1)、(20.4±2.1)mm.手术前后瓣环周长、瓣环横径和瓣环纵径差异均有统计学意义(均P <0.05).在收缩期,前瓣环与后瓣环之间夹角较大,在舒张期,前叶侧瓣环与后叶侧瓣环之间夹角较小.二尖瓣成形术后二尖瓣瓣环周长、横径、纵径较术前有减少.术前二尖瓣横径和纵径测量值几乎相同,在术后则纵径/横径达到93%.瓣环高度由术前(8.4±0.6) mm降低到术后的(3.0±0.1)mm,瓣环高度/横径比值由术前24%降低到14%.前后瓣环非平面夹角在成形术后由(135±14)°增加为(145±13)°,与术前比较,差异均有统计学意义(均P<0.05).结论 二尖瓣成形术后瓣环空间构型会由于人工瓣环的使用而发生变化.%Objective To investigate the configuration changes after mitral repair by three dimensional echocardiography in the operation room.Methods Serious mitral prolapse without other cardiac disorders were chosen.The routine two dimensional echocardiography was performed after admission.3 dimensional

  9. 三维斑点追踪成像评价心肌存活性的临床研究%Assessment of myocardial viability by three-dimensional speckle tracking echocardiography

    Institute of Scientific and Technical Information of China (English)

    冉红; 张平洋; 张幼祥; 张建鑫; 吴文芳; 董静; 马小五

    2014-01-01

    够作为临床提供有效区分存活与非存活心肌的新途径.%Objective To investigate the role of three-dimensional speckle tracking echocardiography (3D-STE) in providing a novel approach to assessing myocardial viability in patients with myocardial infarction (MI).Methods The subjects from the Department of Cardiology and the Department of Cardiac Surgery admitted from April 2010 through December 2012 were diagnosed as MI by electrocardiogram,myocardial enzymes and angiography.The clear imaging of angiography was selected out and collected.All patients had different degrees of segmental wall motion abnormalities,and some already had percutaneous transluminal coronary angioplasty and coronary stenting or coronary artery bypass grafting.Patients with diabetes,heart disease and severe valvular disease of heart were excluded.A total of 45 MI patients were checked with routine echocardiography,two-dimensional speckle tracking echocardiography (2D-STE) and 3D-STE.Then,radionuclide myocardial perfusion/metabolic imaging was served as a "golden standard" to distinguish the viable from nonviable myocardium in each patient within a day.In order to determine the most sensitivity and specificity threshold values of circumferential peak-systolic strain (Cs),longitudinal peak-systolic strain (Ls),radial peak-systolic strain (Rs),3D strain and area strain for viability detection from 3D-STE,the receiver operating characteristic curve was used to investigate the sensitivity and specificity of the detection of viable myocardium with strain parameters in the study.Comparisons between viable and non-viable groups were carried out with t test.Data were expressed as the mean value ± standard deviation (-x ± s).Results The ventricular wall motion abnormality by visual assessment was observed in 368 segments from 720 segments in 45 patients.Furthermore,204 segments were confirmed to be viable by radionuclide myocardial perfusion/metabolic imaging whereas the rest 164

  10. Three-dimensional photovoltaics

    Science.gov (United States)

    Myers, Bryan; Bernardi, Marco; Grossman, Jeffrey C.

    2010-03-01

    The concept of three-dimensional (3D) photovoltaics is explored computationally using a genetic algorithm to optimize the energy production in a day for arbitrarily shaped 3D solar cells confined to a given area footprint and total volume. Our simulations demonstrate that the performance of 3D photovoltaic structures scales linearly with height, leading to volumetric energy conversion, and provides power fairly evenly throughout the day. Furthermore, we show that optimal 3D shapes are not simple box-like shapes, and that design attributes such as reflectivity can be optimized in new ways using three-dimensionality.

  11. Two- and three-dimensional gravity modeling along western continental margin and intraplate Narmada-Tapti rifts: Its relevance to Deccan flood basalt volcanism

    Indian Academy of Sciences (India)

    Somdev Bhattacharji; Rajesh Sharma; Nilanjan Chatterjee

    2004-12-01

    The western continental margin and the intraplate Narmada-Tapti rifts are primarily covered by Deccan flood basalts. Three-dimensional gravity modeling of +70 mgal Bouguer gravity highs extending in the north-south direction along the western continental margin rift indicates the presence of a subsurface high density, mafic-ultramafic type, elongated, roughly ellipsoidal body. It is approximately 12.0 ± 1.2 km thick with its upper surface at an approximate depth of 6.0 ± 0.6km, and its average density is 2935 kg/m3. Calculated dimension of the high density body in the upper crust is 300 ± 30km in length and 25 ± 2.5 to 40 ± 4 km in width. Three-dimensional gravity modeling of +10 mgal to −30 mgal Bouguer gravity highs along the intraplate Narmada-Tapti rift indicates the presence of eight small isolated high density mafic bodies with an average density of 2961 kg/m3. These mafic bodies are convex upward and their top surface is estimated at an average depth of 6.5 ± 0.6 (between 6 and 8 km). These isolated mafic bodies have an average length of 23.8 ± 2.4 km and width of 15.9 ± 1.5 km. Estimated average thickness of these mafic bodies is 12.4 ± 1.2 km. The difference in shape, length and width of these high density mafic bodies along the western continental margin and the intraplate Narmada-Tapti rifts suggests that the migration and concentration of high density magma in the upper lithosphere was much more dominant along the western continental margin rift. Based on the three-dimensional gravity modeling, it is conjectured that the emplacement of large, ellipsoidal high density mafic bodies along the western continental margin and small, isolated mafic bodies along the Narmada-Tapti rift are related to lineamentreactivation and subsequent rifting due to interaction of hot mantle plume with the lithospheric weaknesses (lineaments) along the path of Indian plate motion over the R´eunion hotspot. Mafic bodies formed in the upper lithosphere as

  12. Three-dimensional metamaterials

    Science.gov (United States)

    Burckel, David Bruce [Albuquerque, NM

    2012-06-12

    A fabrication method is capable of creating canonical metamaterial structures arrayed in a three-dimensional geometry. The method uses a membrane suspended over a cavity with predefined pattern as a directional evaporation mask. Metallic and/or dielectric material can be evaporated at high vacuum through the patterned membrane to deposit resonator structures on the interior walls of the cavity, thereby providing a unit cell of micron-scale dimension. The method can produce volumetric metamaterial structures comprising layers of such unit cells of resonator structures.

  13. Three dimensional system integration

    CERN Document Server

    Papanikolaou, Antonis; Radojcic, Riko

    2010-01-01

    Three-dimensional (3D) integrated circuit (IC) stacking is the next big step in electronic system integration. It enables packing more functionality, as well as integration of heterogeneous materials, devices, and signals, in the same space (volume). This results in consumer electronics (e.g., mobile, handheld devices) which can run more powerful applications, such as full-length movies and 3D games, with longer battery life. This technology is so promising that it is expected to be a mainstream technology a few years from now, less than 10-15 years from its original conception. To achieve thi

  14. Three-Dimensional Complex Variables

    Science.gov (United States)

    Martin, E. Dale

    1988-01-01

    Report presents new theory of analytic functions of three-dimensional complex variables. While three-dimensional system subject to more limitations and more difficult to use than the two-dimensional system, useful in analysis of three-dimensional fluid flows, electrostatic potentials, and other phenomena involving harmonic functions.

  15. Comparison of two- and three-dimensional quantitative coronary angiography to intravascular ultrasound in the assessment of intermediate left main stenosis.

    Science.gov (United States)

    Porto, Italo; Dato, Ilaria; Todaro, Daniel; Calabrese, Michele; Rigattieri, Stefano; Leone, Antonio Maria; Niccoli, Giampaolo; Burzotta, Francesco; Trani, Carlo; Crea, Filippo

    2012-06-01

    Angiographic evaluation of intermediate left main coronary artery stenosis (LMS) is often limited. Three-dimensional (3D) quantitative coronary angiography has recently developed to overcome 2-dimensional (2D) quantitative coronary angiographic (QCA) limitations. In patients with angiographically intermediate LMS, we investigated whether 3D quantitative coronary angiography was superior to 2D quantitative coronary angiography in predicting the presence of a significant LMS, defined as a minimum luminal area <6 mm(2) at intravascular ultrasound (IVUS). 2D and 3D quantitative coronary angiography were compared in their measurements of minimum luminal area, percent area stenosis, minimum luminal diameter, and percent diameter stenosis and in their prediction of an IVUS minimum luminal area <6 mm(2). In total 58 target lesions were interrogated, 25 (43%) of which had an IVUS minimum luminal area <6 mm(2). Correlation between 3D-QCA minimum luminal area and IVUS minimum luminal area was stronger than the correlation between 2D-QCA minimum luminal area (or minimum luminal diameter) and IVUS minimum luminal area (R = 0.67, p = 0.0001, and R = 0.40, p = 0.001, respectively, p = 0.04 for comparison). To predict IVUS minimum luminal area <6 mm(2), the most accurate 2D-QCA measurement was minimum luminal diameter (area under curve 0.81, cutoff 2.2 mm, p = 0.0001), and the most accurate 3D-QCA measurement was minimum luminal area (area under curve 0.86, cutoff 5.6 mm(2), p = 0.0001). 2D-QCA percent diameter stenosis did not significantly predict IVUS minimum luminal area <6 mm(2) (area under curve 0.56, cutoff 38%, p = 0.45). In conclusion, the accuracy of quantitative coronary angiography in predicting LM IVUS minimum luminal area <6 mm(2) is limited. When IVUS is not available or contraindicated, 3D quantitative coronary angiography may assist in the evaluation of intermediate LMS. Among 2D-QCA parameters, minimum luminal diameter is more accurate than percent diameter

  16. Si/SiGe heterointerfaces in one-, two-, and three-dimensional nanostructures: their impact on SiGe light emission

    Science.gov (United States)

    Lockwood, David; Wu, Xiaohua; Baribeau, Jean-Marc; Mala, Selina; Wang, Xialou; Tsybeskov, Leonid

    2016-03-01

    Fast optical interconnects together with an associated light emitter that are both compatible with conventional Si-based complementary metal-oxide- semiconductor (CMOS) integrated circuit technology is an unavoidable requirement for the next-generation microprocessors and computers. Self-assembled Si/Si1-xGex nanostructures, which can emit light at wavelengths within the important optical communication wavelength range of 1.3 - 1.55 μm, are already compatible with standard CMOS practices. However, the expected long carrier radiative lifetimes observed to date in Si and Si/Si1-xGex nanostructures have prevented the attainment of efficient light-emitting devices including the desired lasers. Thus, the engineering of Si/Si1-xGex heterostructures having a controlled composition and sharp interfaces is crucial for producing the requisite fast and efficient photoluminescence (PL) at energies in the range 0.8-0.9 eV. In this paper we assess how the nature of the interfaces between SiGe nanostructures and Si in heterostructures strongly affects carrier mobility and recombination for physical confinement in three dimensions (corresponding to the case of quantum dots), two dimensions (corresponding to quantum wires), and one dimension (corresponding to quantum wells). The interface sharpness is influenced by many factors such as growth conditions, strain, and thermal processing, which in practice can make it difficult to attain the ideal structures required. This is certainly the case for nanostructure confinement in one dimension. However, we demonstrate that axial Si/Ge nanowire (NW) heterojunctions (HJs) with a Si/Ge NW diameter in the range 50 - 120 nm produce a clear PL signal associated with band-to-band electron-hole recombination at the NW HJ that is attributed to a specific interfacial SiGe alloy composition. For three-dimensional confinement, the experiments outlined here show that two quite different Si1-xGex nanostructures incorporated into a Si0.6Ge0.4 wavy

  17. Si/SiGe heterointerfaces in one-, two-, and three-dimensional nanostructures: their impact on SiGe light emission

    Directory of Open Access Journals (Sweden)

    David J. Lockwood

    2016-03-01

    Full Text Available Fast optical interconnects together with an associated light emitter that are both compatible with conventional Si-based complementary metal-oxide- semiconductor (CMOS integrated circuit technology is an unavoidable requirement for the next-generation microprocessors and computers. Self-assembled Si/Si1-xGex nanostructures, which can emit light at wavelengths within the important optical communication wavelength range of 1.3 – 1.55 μm, are already compatible with standard CMOS practices. However, the expected long carrier radiative lifetimes observed to date in Si and Si/Si1-xGex nanostructures have prevented the attainment of efficient light-emitting devices including the desired lasers. Thus, the engineering of Si/Si1-xGex heterostructures having a controlled composition and sharp interfaces is crucial for producing the requisite fast and efficient photoluminescence (PL at energies in the range 0.8-0.9 eV. In this paper we assess how the nature of the interfaces between SiGe nanostructures and Si in heterostructures strongly affects carrier mobility and recombination for physical confinement in three dimensions (corresponding to the case of quantum dots, two dimensions (corresponding to quantum wires, and one dimension (corresponding to quantum wells. The interface sharpness is influenced by many factors such as growth conditions, strain, and thermal processing, which in practice can make it difficult to attain the ideal structures required. This is certainly the case for nanostructure confinement in one dimension. However, we demonstrate that axial Si/Ge nanowire (NW heterojunctions (HJs with a Si/Ge NW diameter in the range 50 – 120 nm produce a clear PL signal associated with band-to-band electron-hole recombination at the NW HJ that is attributed to a specific interfacial SiGe alloy composition. For three-dimensional confinement, the experiments outlined here show that two quite different Si1-xGex nanostructures incorporated into a Si

  18. Real-Time Three-Dimensional Echocardiography as a Novel Approach to Quantify Left Ventricular Dyssynchrony: A Comparison Study with Phase Analysis of Gated Myocardial Perfusion Single Photon Emission Computed Tomography

    Science.gov (United States)

    Marsan, Nina Ajmone; Henneman, Maureen M.; Chen, Ji; Ypenburg, Claudia; Dibbets, Petra; Ghio, Stefano; Bleeker, Gabe B.; Stokkel, Marcel P.; van der Wall, Ernst E.; Tavazzi, Luigi; Garcia, Ernest V.; Bax, Jeroen J.

    2010-01-01

    Background Different imaging modalities have been explored for assessment of left ventricular (LV) dyssynchrony. Gated myocardial perfusion single photon emission computed tomography (GMPS) with phase analysis is a reliable technique to quantify LV dyssynchrony and predict response to cardiac resynchronization therapy. Objective Real-time 3-dimensional echocardiography (RT3DE) is a novel imaging technique that provides a LV systolic dyssynchrony index, based on regional volumetric changes as a function of time and calculated as the SD of time to minimum systolic volume of 16 standard myocardial segments expressed in percentage of cardiac cycle. The aim of this study was to compare LV dyssynchrony evaluated with GMPS with LV dyssynchrony assessed with RT3DE. Methods The study population consisted of 40 patients with heart failure who underwent both GMPS and RT3DE. Results Good correlations between LV dyssynchrony assessed with RT3DE and GMPS were demonstrated (r = 0.76 for histogram bandwidth, r = 0.80 for phase SD, P < .0001). Patients with substantial LV dyssynchrony on GMPS (defined as ≥135 degrees for histogram bandwidth and ≥43 degrees for phase SD) had significantly higher LV systolic dyssynchrony index than patients without substantial LV dyssynchrony. Conclusions The good correlations between LV dyssynchrony assessed with GMPS and with RT3DE provide further support for the use of RT3DE for reliable assessment of LV dyssynchrony. PMID:18222645

  19. Three dimensional Dirac semimetals

    Science.gov (United States)

    Zaheer, Saad

    We extend the physics of graphene to three dimensional systems by showing that Dirac points can exist on the Fermi surface of realistic materials in three dimensions. Many of the exotic electronic properties of graphene can be ascribed to the pseudorelativistic behavior of its charge carriers due to two dimensional Dirac points on the Fermi surface. We show that certain nonsymmorphic spacegroups exhibit Dirac points among the irreducible representations of the appropriate little group at high symmetry points on the surface of the Brillouin zone. We provide a list of all Brillouin zone momenta in the 230 spacegroups that can host Dirac points. We describe microscopic considerations necessary to design materials in one of the candidate spacegroups such that the Dirac point appears at the Fermi energy without any additional non-Dirac-like Fermi pockets. We use density functional theory based methods to propose six new Dirac semimetals: BiO 2 and SbO2 in the beta-cristobalite lattice (spacegroup 227), and BiCaSiO4, BiMgSiO4, BiAlInO 4, and BiZnSiO4 in the distorted spinels lattice (spacegroup 74). Additionally we derive effective Dirac Hamiltonians given group representative operators as well as tight binding models incorporating spin-orbit coupling. Finally we study the Fermi surface of zincblende (spacegroup 216) HgTe which is effectively point-like at Gamma in the Brillouin zone and exhibits accidental degeneracies along a threefold rotation axis. Whereas compressive strain gaps the band structure into a topological insulator, tensile strain shifts the accidental degeneracies away from Gamma and enlarges the Fermi surface. States on the Fermi surface exhibit nontrivial spin texture marked by winding of spins around the threefold rotation axis and by spin vortices indicating a change in the winding number. This is confirmed by microscopic calculations performed in tensile strained HgTe and Hg0.5Zn 0.5 Te as well as k.p theory. We conclude with a summary of recent

  20. Three-dimensional mixed-wet random pore-scale network modeling of two- and three-phase flow in porous media. II. Results.

    Science.gov (United States)

    Piri, Mohammad; Blunt, Martin J

    2005-02-01

    We use the model described in Piri and Blunt [Phys. Rev. E 71, 026301 (2005)] to predict two- and three-phase relative permeabilities of Berea sandstone using a random network to represent the pore space. We predict measured relative permeabilities for two-phase flow in a water-wet system. We then successfully predict the steady-state oil, water, and gas three-phase relative permeabilities measured by Oak (Proceedings of the SPE/DOE Seventh Symposium on Enhanced Oil Recovery, Tulsa, OK, 1990). We also study secondary and tertiary gas injection into media of different wettability and initial oil saturation and interpret the results in terms of pore-scale displacement processes.

  1. 4DCAPTURE: a general purpose software package for capturing and analyzing two- and three-dimensional motion data acquired from video sequences

    Science.gov (United States)

    Walton, James S.; Hodgson, Peter; Hallamasek, Karen; Palmer, Jake

    2003-07-01

    4DVideo is creating a general purpose capability for capturing and analyzing kinematic data from video sequences in near real-time. The core element of this capability is a software package designed for the PC platform. The software ("4DCapture") is designed to capture and manipulate customized AVI files that can contain a variety of synchronized data streams -- including audio, video, centroid locations -- and signals acquired from more traditional sources (such as accelerometers and strain gauges.) The code includes simultaneous capture or playback of multiple video streams, and linear editing of the images (together with the ancilliary data embedded in the files). Corresponding landmarks seen from two or more views are matched automatically, and photogrammetric algorithms permit multiple landmarks to be tracked in two- and three-dimensions -- with or without lens calibrations. Trajectory data can be processed within the main application or they can be exported to a spreadsheet where they can be processed or passed along to a more sophisticated, stand-alone, data analysis application. Previous attempts to develop such applications for high-speed imaging have been limited in their scope, or by the complexity of the application itself. 4DVideo has devised a friendly ("FlowStack") user interface that assists the end-user to capture and treat image sequences in a natural progression. 4DCapture employs the AVI 2.0 standard and DirectX technology which effectively eliminates the file size limitations found in older applications. In early tests, 4DVideo has streamed three RS-170 video sources to disk for more than an hour without loss of data. At this time, the software can acquire video sequences in three ways: (1) directly, from up to three hard-wired cameras supplying RS-170 (monochrome) signals; (2) directly, from a single camera or video recorder supplying an NTSC (color) signal; and (3) by importing existing video streams in the AVI 1.0 or AVI 2.0 formats. The

  2. Three-dimensional ultrasound scanning.

    Science.gov (United States)

    Fenster, Aaron; Parraga, Grace; Bax, Jeff

    2011-08-06

    The past two decades have witnessed developments of new imaging techniques that provide three-dimensional images about the interior of the human body in a manner never before available. Ultrasound (US) imaging is an important cost-effective technique used routinely in the management of a number of diseases. However, two-dimensional viewing of three-dimensional anatomy, using conventional two-dimensional US, limits our ability to quantify and visualize the anatomy and guide therapy, because multiple two-dimensional images must be integrated mentally. This practice is inefficient, and may lead to variability and incorrect diagnoses. Investigators and companies have addressed these limitations by developing three-dimensional US techniques. Thus, in this paper, we review the various techniques that are in current use in three-dimensional US imaging systems, with a particular emphasis placed on the geometric accuracy of the generation of three-dimensional images. The principles involved in three-dimensional US imaging are then illustrated with a diagnostic and an interventional application: (i) three-dimensional carotid US imaging for quantification and monitoring of carotid atherosclerosis and (ii) three-dimensional US-guided prostate biopsy.

  3. Evaluation of left ventricular systolic function in patients with dilated cardiomyopathy by real-time three-dimensional speckle tracking echocardiography%实时三维超声心动图斑点追踪技术评价扩张型心肌病患者左室收缩功能

    Institute of Scientific and Technical Information of China (English)

    李阳; 邓又斌; 黄润青; 孙杰; 刘琨; 汤乔颖

    2013-01-01

    目的 应用实时三维超声心动图斑点追踪技术评价扩张型心肌病(DCM)患者左室收缩功能.方法 应用实时三维超声斑点追踪技术分别测量24例DCM患者(DCM组)和19例健康成人志愿者(对照组)左室收缩期纵向、圆周向、径向以及面积应变峰值,比较两组左室心肌基底部、中间部及心尖部局部应变和总体应变的差异,并分析总体应变与左室射血分数的相关性.结果 DCM组左室心肌纵向、圆周向、径向及面积的基底部、中间部、心尖部局部应变和心肌总体应变均明显小于对照组对应节段,差异均有统计学意义(均P<0.01).左室心肌纵向、圆周向、径向以及面积总体应变均与左室射血分数有良好的相关性(r=0.873、0.862、0.885及0.894,均P<0.01).结论 实时三维超声心动图斑点追踪技术可以为DCM的诊断、疗效评估以及预后判断提供较好的检测手段,具有较大的临床价值.%Objective To evaluate the systolic function of the left ventricle in patients with dilated cardiomyopathy by real-time three-dimensional speckle tracking echocardiography.Methods The peak systolic longitudinal train,circumferential stain,radial strain and area strain of left ventricle were measued by real time three-dimensional speckle tracking echocardiography technology in 24 patients with dilated cardiomyopathy (DCM group) and 19 healthy volunteers (control group).The difference of regional myocardial strain of basal,middle,apical level and global myocardial strain were compared between the two groups.The correlation between global myocardial strain in all directions and left ventricular ejection fraction was analyzed.Results The global and each level longitudinal strain,circumferential strain,radial strain and area strain in DCM group were significantly lower than those in control group(P<0.01).The global myocardial longitudinal train,circumferential stain,radial strain and area strain were

  4. Evaluation of the structure of tricuspid valve with three dimensional echocardiography in hypoplastic right ventricle%三维超声心动图评估发育不良型三尖辦结构的价值

    Institute of Scientific and Technical Information of China (English)

    陈笋; 孙锟; 陈树宝; 张玉奇; 张志芳; 吴兰萍

    2009-01-01

    目的 应用三维超声心动图探讨右心室发育不良时三尖辦装置的结构特点.方法 28例诊断为右心室发育不良的患儿,按照三尖辦反流程度分为反流组(三尖辦反流中度及以上)与非反流组(三尖辦反流轻度及以下).18例年龄匹配的正常儿童作为对照组.应用实时三维超声心动图测定右心室容积、三尖辦辦环面积、三尖辦各辦叶的面积以及辦尖至最近乳头肌顶点的距离.测值应用体表面积(USA)进行标化.结果 右心室发育不良患儿组的右心室容积显著低于正常组,三尖辦辦环面积与右心室容积显著相关(r=0.90,P<0.0001).在三尖辦反流组,三尖辦前辦面积与辦环面积的比值较非反流组以及正常组显著增加,而后辦所占比值显著缩小.右心发育不良组各辦尖至相邻乳头肌顶点的距离显著小于正常组.反流组隔辦辦尖至相邻乳头肌距离显著小于非反流组(P=0.0023).结论 三维超声心动图可以用来评估先天性心脏病三尖辦病变.右心室发育不良患儿后辦发育不良以及隔辦腱索偏短可能是三尖辦反流的原因.%Objective To reveal the character of tricuspid valve in hypoplastic right ventricular heart syndrome (HPRVHS) using 3-dimensional echocardiography(3DE). Methods Twenty eight patients with HPRVHS were included in the study, and they were divided into two groups according the degree of tricuspid regurgitation. Eighteen normal children were included as the control. Volume of right ventricle(VRV), area of tricuspid annulus(TVA),proportion of the leaflets and the distance from tips of leaflets to the nearest papillary muscle were measured with 3DE. These data was standardized by body surface area. Results The volume of right ventricle in HPRVHS was significantly less than that in normal group. The area of tricuspid annulus was significantly correlated with volume of right ventricle(r = 0. 90, P < 0. 0001). In the tricuspid regurgitation

  5. Comprehensive knowledge base of two- and three-dimensional activity cliffs for medicinal and computational chemistry [v1; ref status: indexed, http://f1000r.es/5ir

    Directory of Open Access Journals (Sweden)

    Ye Hu

    2015-06-01

    Full Text Available Activity cliffs are formed by pairs or groups of structurally similar or analogous active compounds with large differences in potency. They can be defined in two or three dimensions by comparing graph-based molecular representations or compound binding modes, respectively. Through systematic analysis of publicly available compound activity data and ligand-target X-ray structures we have in a series of studies determined all currently available two- and three-dimensional activity cliffs (2D- and 3D-cliffs, respectively. Furthermore, we have systematically searched for 2D extensions of 3D-cliffs. Herein, we specify different categories of activity cliffs we have explored and introduce an open access data deposition in ZENODO (doi: 10.5281/zenodo.18490 that makes the entire knowledge base of current activity cliffs freely available in an organized form.

  6. Dynamic 3D echocardiography in virtual reality.

    NARCIS (Netherlands)

    A.E. van den Bosch (Annemien); A.H.J. Koning (Anton); F.J. Meijboom (Folkert); J.S. McGhie (Jackie); M.L. Simoons (Maarten); P.J. van der Spek (Peter); A.J.J.C. Bogers (Ad)

    2005-01-01

    textabstractBACKGROUND: This pilot study was performed to evaluate whether virtual reality is applicable for three-dimensional echocardiography and if three-dimensional echocardiographic 'holograms' have the potential to become a clinically useful tool. METHODS: Three-dimensional echocardiographic d

  7. 实时三维超声心动图容积-时间曲线评价心力衰竭患者左室舒张功能的研究%Evaluation of left ventricular diastolic function in patients with heart failure using volume-time curve by real-time three-dimensional echocardiography

    Institute of Scientific and Technical Information of China (English)

    阮坚; 潘永寿; 庾红玉; 秦蕾; 冯红兵; 皮永前

    2013-01-01

    Objective To evaluate left ventricular diastolic function in patients with heart failure (HF) using volume-time curve (VTC) by real-time three-dimensional echocardiography (RT-3DE).Methods The left ventricular peak filling rate (PFR) in 104 patients With HF and 74 Healthy volunteers using VTC by RT-3DE were measured and compared.Results PFR in patients with HF was significantly lower than the normal control subjects (P <0.01).Conclusion VTC of RT3DE can measure left ventricular PFR accurately,and evaluate left ventricular diastolic function in patients with HF.%目的 应用实时三维超声心动图(TR-3DE)容积-时间曲线(VTC)评价心力衰竭患者左室舒张功能.方法 应用TR-3DE的左室VTC测量104例心力衰竭患者和74例正常人的左室峰值充盈率(PFR),并进行比较.结果 心力衰竭患者的PFR明显小于正常对照组(P<0.001).结论 TR-3DE VTC可以准确测量左室PFR,能评价心力衰竭患者左室舒张功能状况.

  8. 实时三维超声心动图斑点追踪技术评价移植心脏左心室收缩功能%Left ventricular systolic function evaluated by real-time three-dimensional speckle tracking echocardiography in heart transplant recipients

    Institute of Scientific and Technical Information of China (English)

    刘红云; 邓又斌; 刘琨; 李阳; 汤乔颖; 魏翔; 昌盛; 卢峡

    2013-01-01

    Objective To evaluate the left ventricular systolic function in the cardiac allograft by real time three-dimensional speckle tracking echocardiography.Methods Twenty-three heart transplant recipients underwent total 57 echocardiographic studies at one,two,three months after heart transplantation.Twenty-three healthy subjects were served as controls.The three-dimensional full-volume images of left ventricle were recorded and then were analyzed using EchoPAC software.The strain curves were obtained and peak strain values of left ventricle for each segment and overall left ventricular wall were measured.Left ventricular global peak longitudinal strain (GPSL),circumferential strain (GPSC),area strain (GPSA) and radial strain (GPSR) were recorded and then statistical analyzed.Results The left ventricular ejection fraction (EF) and cardiac output (CO) in heart transplant recipients had no significant difference when compared with controls.The GPSL reduced significantly one month after surgery in heart transplant recipients than controls,but had no significant difference two months and three months after surgery with controls.The GPSC,GPSA,GPSR decreased significantly in heart transplant recipients (one,two,three months after surgery) than those in controls.Conclusions The left ventricular ejection fraction of cardiac allograft seemed "normal",but the global peak strain of left ventricle were still significantly reduced than controls.Real time three dimensional speckle tracking echocardiography can be used for an accurate assessment of left ventricular systolic function in heart transplant recipients.%目的 应用实时三维超声心动图斑点追踪技术检测移植心脏左室壁峰值收缩应变,探讨实时三维超声心动图斑点追踪技术评价移植心脏左室收缩功能的价值.方法 23例接受心脏移植患者于移植术后1月、2月、3月进行超声心动图检查,共57次.23例正常人作为对照.采集左室的三维全容积图像,应

  9. Three-dimensional echocardiography of a tricuspid valve papillary fibroelastoma

    Directory of Open Access Journals (Sweden)

    Atooshe Rohani

    2017-01-01

    Full Text Available Papillary fibroelastomas (PFE on tricuspid valve (TV are rare, accounting for fewer than 11% of all PFE. Most often they are asymptomatic, and detect on mitral valve. We report a case of a typical chest pain found to be due to papillary fibroelastoma of the tricuspid valve.

  10. 实时三维超声测量右心室容积及收缩功能的可行性研究%Feasibility of real time-three dimensional echocardiography for measuring volume and systolic function of right venticle

    Institute of Scientific and Technical Information of China (English)

    赵景宏; 乔彦; 唐红; 赵超美

    2012-01-01

    Objectives To evaluate the feasibility of real time-three dimensional echocardiography (RT-3DE) for measuring right ventricular volume and right ventricular ejection fraction (RVEF). Correlations of right ventricular volume, RVEF, right ventricular area and right ventricular fractional area change (RVFAC) measured by RT-3DE and two dimensional echocardiography were analyzed. Methods Eighty five patients with rheumatic heart disease who had undergone valvular replacement operation were enrolled in this study. Right ventricular volume and related values of right ventricle measured by RT-3DE, two dimensional echocardiography were imported to Tomtec 4D Cardio View software and manually adjusted. After endocardial boundary tracing, right ventricular end-diastolic volume (RVEDV), right ventricular end-systolic volume (RVESV), RVEF were automatically calculated by software, and right ventricular stroke volume (RVSV) was manually calculated. Correlation analysis, in retative values of right ventricle measured with RT-3DE and two dimensional echocardiography were applied. Results RVEDV,RVESV, RVSV measured with RT-3DE were significantly higher than those measrued with two dimensional echocardiography (P0.05). RVEDV,RVESV,RVSV and RVEF measured with RT-3DE and two dimensional echocardiography were positively correlated (r=0.79, 0.82, 0.68, 0.64; P<0.05). RVEDV, RVESV, RVEF measured with RT-3DE were positively correlated (r=0.76, 0.79, 0.56; P<0.05) with right ventricular end diastolic area, right ventricular end-systolic area and RVFAC measured with two dimensional echocardiography. Conclusions Right ventricular volume and RVEF measured with RT-3DE are feasible, which are positively correlated with those measured with two dimensional echocardiography. RT-3DE is better for evaluating the systolic function of right ventricle.%目的 分析实时三维超声心动图(RT-3DE)定量测量右心室容积和右心室射血分数(right ventricular ejection fraction,RVEF)的可行

  11. Creating Three-Dimensional Scenes

    Science.gov (United States)

    Krumpe, Norm

    2005-01-01

    Persistence of Vision Raytracer (POV-Ray), a free computer program for creating photo-realistic, three-dimensional scenes and a link for Mathematica users interested in generating POV-Ray files from within Mathematica, is discussed. POV-Ray has great potential in secondary mathematics classrooms and helps in strengthening students' visualization…

  12. Three-dimensional echocardiographic assessment of the repaired mitral valve.

    Science.gov (United States)

    Maslow, Andrew; Mahmood, Feroze; Poppas, Athena; Singh, Arun

    2014-02-01

    This study examined the geometric changes of the mitral valve (MV) after repair using conventional and three-dimensional echocardiography. Prospective evaluation of consecutive patients undergoing mitral valve repair. Tertiary care university hospital. Fifty consecutive patients scheduled for elective repair of the mitral valve for regurgitant disease. Intraoperative transesophageal echocardiography. Assessments of valve area (MVA) were performed using two-dimensional planimetry (2D-Plan), pressure half-time (PHT), and three-dimensional planimetry (3D-Plan). In addition, the direction of ventricular inflow was assessed from the three-dimensional imaging. Good correlations (r = 0.83) and agreement (-0.08 +/- 0.43 cm(2)) were seen between the MVA measured with 3D-Plan and PHT, and were better than either compared to 2D-Plan. MVAs were smaller after repair of functional disease repaired with an annuloplasty ring. After repair, ventricular inflow was directed toward the lateral ventricular wall. Subgroup analysis showed that the change in inflow angle was not different after repair of functional disease (168 to 171 degrees) as compared to those presenting with degenerative disease (168 to 148 degrees; p<0.0001). Three-dimensional imaging provides caregivers with a unique ability to assess changes in valve function after mitral valve repair. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Evaluation of left ventricular strain by real-time three-dimensional speckle tracking echocardiography in patients with hypertension and myocardial hypertrophy%实时三维超声心动图斑点追踪技术测量高血压心肌肥厚患者收缩期左室心肌应变

    Institute of Scientific and Technical Information of China (English)

    汤乔颖; 邓又斌; 黄润青; 刘琨; 孙杰; 邓琪

    2013-01-01

    Objective To investigate left ventricular (LV) strain in patients with hypertension (HT)and myocardial hypertrophy using three-dimensional speckle tracking echocardiography.Methods Myocardial movement was analyzed in 37 primary HT patients with myocardial hypertrophy and 27 healthy volunteers.LV longitudinal,circumferential,radial and area strains were measured.The correlation between each global strain parameter and LV ejection fraction (LVEF) was analyzed.Results LV global longitudinal strain(GSL),global radial strain (GSR) and global area strain (GSA) of HT patients with myocardial hypertrophy were significantly lower than the contrast group,whereas global circumferential strain(GSC) showed no significant difference between the two groups.Longitudinal,radial and area strains were decreased in LV basal and middle levels,while decreased circumferential strain was detected only in basal level.There were significant correlations between LVEF and GSL,GSC,GSR,GSA.Conclusions Impairment of LV regional myocardial contractility can be detected by three-dimensional speckle tracking echocardiography.%目的 采用实时三维超声心动图斑点追踪技术研究原发性高血压心肌肥厚患者的收缩期左室心肌应变特点.方法 采用三维超声心动图斑点追踪技术对37例原发性高血压心肌肥厚患者及27例健康志愿者进行了室壁运动分析,测量左室纵向、圆周向、径向、面积应变,比较两组间各应变参数的差异,并分析各项整体应变参数与左室射血分数(LVEF)的相关性.结果 高血压心肌肥厚患者的左室整体纵向、径向和面积应变较正常对照组明显减低,左室整体圆周向应变与对照组间无明显差异.纵向、径向、圆周向应变在左室基底段、中段明显减低,圆周向应变减低仅见于基底段.左室整体纵向、圆周向、径向、面积应变与LVEF具有相关性.结论 实时三维超声心动图斑点追踪技术可检测到高血压心

  14. Clinical study on the left ventricular diastolic function of hypertrophy by real-time three-dimensional echocardiography and quantitative tissue velocity imaging%实时三维超声心动图和定量组织速度成像对高血压患者左心室舒张功能的研究

    Institute of Scientific and Technical Information of China (English)

    赵可辉; 刘翠红; 艾阳平

    2011-01-01

    Objective: To asscss the feasibility and accuraey of real-time three-dimensional echocardiography (RT-3DE) and quantitative tissue velocity imaging( QTVI) in quantifying left ventricular diastolic function.Methods : Twenty healthy volunteers without cardiovascular diseases and twenty patients with left ventricular hypertrophy were investigated, and the quantitative analyses were blinded to each other.To measure the left vcntricular mass (LVM) , peak filling rate (PFR) of thcm by realtime three-dimensional echocardiography (RT-3DE).To measure tissue move ahead duration midpt (TMAD Midpt) , pcak myocardial sustaincd early diastolic velocity (Ve) , peak myocardial sustained late diastolic velocity (Va) of them by quantitative tissue velocity imaging (QTVI).Results: Clear cndocardial border, real-time three-dimensional and two-dimensional images were obtained in all 40 cases.There were significant differences of left ventricular mass ( LVM) , left ventricular mass index (LVMI) , filling rate (PFR) between the two groups ( P <0.01).Mitral annulus maximum displacement (TMAD Midpt) also showed significant differences between the measured values ( P <0.01).Scpta2, lateral basal segment of left ventricular carly diastolic and late diastolic peak velocity (Ve, Va) and the ratio (Ve / Va) showed significant difference between measured values ( P <0.01).Left ventricular filling rate (PFR) , left ventricular septal and latcral basal diastolic peak early and late diastolic velocity ratio (Ve / Va) , the largest midpoint of mitral annular displacemcnt (TMAD Midpt) had a high correlation with the carly diastolic and late diastolic velocity ratio ( E/A) on traditional two-dimensional echocardiography test, the correlation coefficients were 0.962, 0.961, 0.434.Conclusion: Diastolic function left ventricular in healthy adult and patients with left ventricular hypertrophy has heterogeneity.RT-3DE and QTVI provides a new method in assessing the left ventricular function.%目

  15. 经食管实时三维超声在主动脉瓣狭窄患者瓣环径定量中的应用%Application of the real-time three-dimensional transesophageal echocardiography in the quantification of aortic anuulus diameter in patients with aortic stenosis

    Institute of Scientific and Technical Information of China (English)

    孔令秋; 唐红; 魏薪; 康彧; 任奔; 宋海波

    2013-01-01

    目的 探讨经食管实时三维超声心动图(RT-3D TEE)在主动脉瓣狭窄患者主动脉瓣环径定量分析中的应用价值.方法 65例因重度主动脉瓣狭窄行外科手术者,术中采集主动脉根部RT-3D TEE图像,运用瓣环定量软件重建主动脉瓣环,生成瓣环参数并计算基于此的瓣环径(3D-A-AAD、3D-C-AAD),并将其与外科测瓣器测值(IO-AAD)进行一致性分析.结果 基于三维瓣环参数的主动脉瓣环径3D-A-AAD和3D-C-AAD分别为(22.4±2.1)mm、(23.4±1.9)mm.二者测值与术IO-AAD[(23.4±2.2)mm]相比,差异均无统计学意义(P<0.05),与3D-A-AAD相比,3D-C-AAD与IO-AAD的一致性较好.结论 RT-3D TEE及瓣环定量分析软件不仅能重建主动脉瓣环三维形态,还可用作瓣环径定量分析工具.%Objective To investigate the application of real-time three-dimensional transesophageal echocardiography (RT-3D TEE) in quantification of the aortic anuulus diameter in patients with severe aortic stenosis.Methods RT-3D TEE image of aortic root was get perioperatively in 65 patients with sever aortic valve stenosis during the surgery procedure.The aortic annulus was reconstructed in the quantitative analysis software to generate the parameters of 3-dimensional area based aortic anuulus diameter(3D-AAAD) and 3-dimensional circumference based aortic anuulus diameter(3D-C-AAD).The parameters was compared with intraoperative aortic anuulus diameter(IO-AAD),which was get by the standard cylindrical valve sizer.Results The three dimensional form of the aortic annulus was related to the number of the valves.The value of 3D-C AAD and 3D-A-AAD were (22.4 ± 2.1) mm,(23.4 ± 1.9) mm,no significant difference could be detected between them and the IO-AAD (P < 0.05).The 3D-C-AAD had a better agreements with IO-AAD than 3D-A-AAD.Conclusions RT-3D TEE can reconstruct the three dimensional sharp of aortic anuulus,and can be used as quantitative tools to calculate its diameter.

  16. Facial three-dimensional morphometry.

    Science.gov (United States)

    Ferrario, V F; Sforza, C; Poggio, C E; Serrao, G

    1996-01-01

    Three-dimensional facial morphometry was investigated in a sample of 40 men and 40 women, with a new noninvasive computerized method. Subjects ranged in age between 19 and 32 years, had sound dentitions, and no craniocervical disorders. For each subject, 16 cutaneous facial landmarks were automatically collected by a system consisting of two infrared camera coupled device (CCD) cameras, real time hardware for the recognition of markers, and software for the three-dimensional reconstruction of landmarks' x, y, z coordinates. From these landmarks, 15 linear and 10 angular measurements, and four linear distance ratios were computed and averaged for sex. For all angular values, both samples showed a narrow variability and no significant gender differences were demonstrated. Conversely, all the linear measurements were significantly higher in men than in women. The highest intersample variability was observed for the measurements of facial height (prevalent vertical dimension), and the lowest for the measurements of facial depth (prevalent horizontal dimension). The proportions of upper and lower face height relative to the anterior face height showed a significant sex difference. Mean values were in good agreement with literature data collected with traditional methods. The described method allowed the direct and noninvasive calculation of three-dimensional linear and angular measurements that would be usefully applied in clinics as a supplement to the classic x-ray cephalometric analyses.

  17. Quasicrystalline three-dimensional foams

    Science.gov (United States)

    Cox, S. J.; Graner, F.; Mosseri, R.; Sadoc, J.-F.

    2017-03-01

    We present a numerical study of quasiperiodic foams, in which the bubbles are generated as duals of quasiperiodic Frank–Kasper phases. These foams are investigated as potential candidates to the celebrated Kelvin problem for the partition of three-dimensional space with equal volume bubbles and minimal surface area. Interestingly, one of the computed structures falls close to (but still slightly above) the best known Weaire–Phelan periodic candidate. In addition we find a correlation between the normalized bubble surface area and the root mean squared deviation of the number of faces, giving an additional clue to understanding the main geometrical ingredients driving the Kelvin problem.

  18. Quantitative assessment of left ventricular function in patients with percutaneous coronary intervention by real-time three-dimensional echocardiography%实时三维超声心动图定量评价冠状动脉介入治疗术后左心功能的研究

    Institute of Scientific and Technical Information of China (English)

    齐清华; 张连仲; 高传玉

    2011-01-01

    目的:探讨实时三维超声心动图(RT-3DE)在评价经皮冠状动脉介入治疗(PCI)术前后患者左心室功能的价值.方法:选择成功接受PCI治疗的患者30例作为冠心病组,无冠状动脉狭窄者20例作为正常对照组,应用RT-3DE对冠心病组于术前3-5天、术后3天及术后1个月测量左室舒张末容积(EDV)、左室收缩末容积(ESV)、左心室射血分数(EF)、峰值射血率(PER)、峰值充盈率(PFR)、达到最小收缩容积时间的标准差(Tmsv16-SD)及最大差值(Tmsv16-Dif),对照组与冠心病组的测值进行比较,PCI术前后测值进行比较.结果:病例组术前EDV、ESV、Tmsv16-SD、Tmsv16-Dif显著增加(P<0.01),EF、PER、PFR显著减小(P<0.01);与术前比较,患者术后EDV、ESV、Tmsv16-SD、Tmsv16-Dif显著减小,整体EF、PER、PFR显著增加(P<0.01).结论:冠心病患者的左心室功能可发生重构,PCI能逆转其重构,RT-3DE可准确评价PCI术后患者左心室功能的逆转.%Objective: To assess the value of real-time three-dimensional echocardiography (RT-3DE) in the evaluation of left ventricular function in patients with coronary artery disease(CAD) after percutaneous coronary intervention(PCI).Methods:RT-3DE was performed in 30 patients who accepted PCI treatment successfully and 20 normal subjects who had no coronary artery stenosis.RT-3DE was performed and three-dimensional image data were analyzed.Seties of left ventricular parameters were measured in 3~5 days pre-, 3 days post- and 1 month post-operation.Left ventricular end-diastolic volume(EDV), endsystolic volume(ESV), ejection fraction(EF), the peak ejection rate(PER), peak filling rate(PFR), the time to the point with minimal systolic volume (Tmsv) in 16 segments standard deviation and the maximal difference of time (Tmsvl6-SD, Tmsvl6-Dif).These parameters were respectively compared.Results: Compared with normal subjects, EDV, ESV, Tmsvl6-SD, Tmsvl6-Dif were significantly increased(P<0.0l).EF, PER and

  19. 实时三维经食管超声心动图在二尖瓣脱垂手术中的应用价值%Clinical values of intraoperative real-time three-dimensional transesophageal echocardiography for surgery in patients with mitral valve prolapse

    Institute of Scientific and Technical Information of China (English)

    许立龙; 赵博文; 李世岩; 钱希明; 何启才; 毛彦恺; 余婵; 潘美

    2012-01-01

    Objective To investigate the value of the intraoperative real-time three-dimensional transesophageal echocardiography (RT 3D-TEE) in therapeutic application of surgery for the mitral valve prolapse.Methods Thirty-five patients underwent surgical treatment were diagnosed as mitral valve prolapse by 2-dimensional transthoracic echocardiography (2D-TTE),with or without ruptured chordae tendineae.RT 3D-TEE was performed for assessing the segment of prolapse and its complications before cardiopulmonary bypass and after heart resuscitation respectively.The echocardiographic results were compared with the surgical findings.Results The accuracy of RT 3D-TEE to identify segments with prolapse was significantly higher than that of 2D-TTE (91.4% vs 82.9%,P =0.003).RT 3D-TEE was more accurate than 2D-TTE for identifying ruptured chordae tendineae,vegetation and thrombus since higher sensitivity,specificity and Youden index.Among all 35 patients,valvuloplasty was performed in 28 cases,whereas,only 7 cases underwent replacement of prosthetic valves.Three patients were benefited by accurate evaluation of therapeutic effect using RT 3D-TEE in time.Conclusions Intraoperative RT 3D-TEE can be used to provide “ surgical view”,acquired adequate valuable information of mitral valve,and more reliable functional and anatomical assessment of the mitral valve components and its geometry.Suitable surgical intervention can be designed for improving outcomes of patients.%目的 探讨术中实时三维经食管超声心动图(RT 3D-TEE)在二尖瓣脱垂患者外科手术治疗中的应用价值.方法 选择经胸超声心动图(2D-TTE)诊断为二尖瓣脱垂(伴或不伴腱索断裂),并进行外科手术治疗的35例患者,于麻醉后体外循环之前行RT 3D-TEE检查,将2D-TTE及RT 3D-TEE结果与术中所见进行比较.并在手术完成心脏复跳后即刻再次进行检查,评价手术疗效.结果 与手术医师术中发现相比较,术中RT 3D-TEE判断

  20. Real-time three-dimensional echocardiography evaluation of left ventricular wall systolic function and correlation with exercise electrocardiography%实时三维超声心动图评价冠心病患者左心室壁节段收缩功能与运动心电图的相关性研究

    Institute of Scientific and Technical Information of China (English)

    艾阳平; 杨海燕

    2013-01-01

    Objective To evaluate the function of segments of left ventricular wall in patients with coronary heart disease and its correlation with exercise electrocardiography by real—time three—dimensional ecbocardiography (RT — 3DE). Methods Thirty healthy persons and 30 patients with coronary heart disease were enrolled in this study. The stroke volume (regional stroke volume, rSV) .end diastolic volume (rEDV), regional radio segment rate ( rEF) of 17 segments of left ventricular wall were measured by real-time three —dimensional echocardiography. And all subjects underwent treadmill exercise test. Results The real-time three-dimensional images with clear endocardia! border and 3.7 scgmental volume—time curves were obtained in both groups. Significant differences were found in rSV,rEDV,rPEF values of 17 segments between the two groups (P<0.05). The segmental function in patients with coronary heart disease and ST segment changes from positive exercise stress test were highly correlated(P<0. 05). Conclusion There is significant difference in left ventricular systolic function between patients with coronary heart disease and health control. The quantitative real —time three —dimensional echocardiography for the evaluation of left ventricular systolic dysfunction and treadmill exercise test in the detection of coronary artery disease are highly correlated,%目的 应用实时三维超声心动图(RT-3DE)评价冠心病患者左心室壁节段功能及其与运动心电图的相关性.方法 冠心病组患者30 例,30 例健康者为对照组,RT-3DE 分别测量其左室壁17 节段的节段每搏量(rSV)、舒张末容积(rEDV)及节段射血率(rPEF),所有受检者进行平板运动试验.结果 两组均获得具有清晰内膜边界的实时三维图像和17 节段容积-时间曲线;两组间17 节段rSV、rEDV、rPEF 测值间差异有统计学意义(P﹤0.05);冠心病患者的节段功能与平板运动试验阳性的ST 段改变高度相关(P﹤0

  1. 常规及实时三维超声心动图在成人Ebstein畸形诊断中的应用价值%Diagnosis of Ebstein anomaly with conventional and transthoracic real-time three-dimensional echocardiography

    Institute of Scientific and Technical Information of China (English)

    江勇; 王浩; 陆敏杰; 万琳媛; 王吴刚; 张茗卉; 吴伟春; 孙欣

    2015-01-01

    ObjectiveTo explore the value of conventional echocardiography and transthoracic real-time three-dimensional echocardiography (RT3DE) in diagnosis of Ebstein anomaly.MethodsWe investigated the morphology and function of right ventricle (RV) as well as the structure, morphology and regurgitation of tricuspid valve in 61 adult patients with Ebstein anomaly before surgery by using conventional echocardiography and transthoracic RT3DE. Twenty normal adults were enrolled as control group. ResultsThe surface of the tricuspid leaflets, the morphology of the tricuspid annulus as well as the three-dimensional structure of the tricuspid valve were displayed stereoscopically by RT3DE. Complete RV volume data could be acquired in 32 patients of Ebstein anomaly. The apex or part of RV could not be contained in the remaining 29 patients. Thirty-four (55.7%) patients with Ebstein anomaly had severe tricuspid regurgitation, 16 (26.2%) patients had moderate to severe regurgitation, and 11 (18.1%) patients had moderate regurgitation. Compared with the normal adults, patients of Ebstein anomaly showed higher RV end-diastolic volume (EDV), end-systolic volume (ESV), end-diastolic volume index (EDVI), end-systolic volume index (ESVI), stroke volume (SV), RV anterior-posterior diameter (RV), tricuspid valve annular transverse diameter (TV-R), and lower RV ejection fraction(EF) [(273.5±77.7) mlvs (74.3±15.9) ml, (187.1±96.8) mlvs (31.1±9.2) ml, (177.4±53.6) ml/m2vs (43.4±8.2) ml/m2, (121.7±65.5) ml/m2vs (18.4±5.1) ml/m2, (95.9±20.2) ml vs (43.6±8.8) ml, (48.1±13.3) ml/m2vs (19.0±1.9) ml/m2, (56.4±8.9) ml/m2vs (28.5±4.3) ml/m2, (38.3±12.8) %vs (59.3±5.1) %, allP<0.05). The tricuspid regurgitant orifice flow cross-sectional area (EROA) were correlated positively with RV anterior-posterior diameter (r=0.691), ratio of RV and LV anterior-posterior diameter (RV/LV) (r=0.6471).ConclusionTransthoracic RT3DE is a feasible method in addition to conventional two

  2. GRID2D/3D: A computer program for generating grid systems in complex-shaped two- and three-dimensional spatial domains. Part 2: User's manual and program listing

    Science.gov (United States)

    Bailey, R. T.; Shih, T. I.-P.; Nguyen, H. L.; Roelke, R. J.

    1990-01-01

    An efficient computer program, called GRID2D/3D, was developed to generate single and composite grid systems within geometrically complex two- and three-dimensional (2- and 3-D) spatial domains that can deform with time. GRID2D/3D generates single grid systems by using algebraic grid generation methods based on transfinite interpolation in which the distribution of grid points within the spatial domain is controlled by stretching functions. All single grid systems generated by GRID2D/3D can have grid lines that are continuous and differentiable everywhere up to the second-order. Also, grid lines can intersect boundaries of the spatial domain orthogonally. GRID2D/3D generates composite grid systems by patching together two or more single grid systems. The patching can be discontinuous or continuous. For continuous composite grid systems, the grid lines are continuous and differentiable everywhere up to the second-order except at interfaces where different single grid systems meet. At interfaces where different single grid systems meet, the grid lines are only differentiable up to the first-order. For 2-D spatial domains, the boundary curves are described by using either cubic or tension spline interpolation. For 3-D spatial domains, the boundary surfaces are described by using either linear Coon's interpolation, bi-hyperbolic spline interpolation, or a new technique referred to as 3-D bi-directional Hermite interpolation. Since grid systems generated by algebraic methods can have grid lines that overlap one another, GRID2D/3D contains a graphics package for evaluating the grid systems generated. With the graphics package, the user can generate grid systems in an interactive manner with the grid generation part of GRID2D/3D. GRID2D/3D is written in FORTRAN 77 and can be run on any IBM PC, XT, or AT compatible computer. In order to use GRID2D/3D on workstations or mainframe computers, some minor modifications must be made in the graphics part of the program; no

  3. Three-dimensional display technologies.

    Science.gov (United States)

    Geng, Jason

    2013-01-01

    The physical world around us is three-dimensional (3D), yet traditional display devices can show only two-dimensional (2D) flat images that lack depth (i.e., the third dimension) information. This fundamental restriction greatly limits our ability to perceive and to understand the complexity of real-world objects. Nearly 50% of the capability of the human brain is devoted to processing visual information [Human Anatomy & Physiology (Pearson, 2012)]. Flat images and 2D displays do not harness the brain's power effectively. With rapid advances in the electronics, optics, laser, and photonics fields, true 3D display technologies are making their way into the marketplace. 3D movies, 3D TV, 3D mobile devices, and 3D games have increasingly demanded true 3D display with no eyeglasses (autostereoscopic). Therefore, it would be very beneficial to readers of this journal to have a systematic review of state-of-the-art 3D display technologies.

  4. Standalone visualization tool for three-dimensional DRAGON geometrical models

    Energy Technology Data Exchange (ETDEWEB)

    Lukomski, A.; McIntee, B.; Moule, D.; Nichita, E. [Faculty of Energy Systems and Nuclear Science, Univ. of Ontario Inst. of Tech., Oshawa, Ontario (Canada)

    2008-07-01

    DRAGON is a neutron transport and depletion code able to solve one-, two- and three-dimensional problems. To date DRAGON provides two visualization modules, able to represent respectively two- and three-dimensional geometries. The two-dimensional visualization module generates a postscript file, while the three dimensional visualization module generates a MATLAB M-file with instructions for drawing the tracks in the DRAGON TRACKING data structure, which implicitly provide a representation of the geometry. The current work introduces a new, standalone, tool based on the open-source Visualization Toolkit (VTK) software package which allows the visualization of three-dimensional geometrical models by reading the DRAGON GEOMETRY data structure and generating an axonometric image which can be manipulated interactively by the user. (author)

  5. Function and mechanics of the left ventricle: from tissue Doppler imaging to three dimensional speckle tracking

    OpenAIRE

    Arias-Godínez,José Antonio; Guadalajara-Boo,José Fernando; Patel, Ayan R; Pandian, Natesa G.

    2011-01-01

    One of the most common indications in echocardiography is the evaluation of left ventricular function. The traditional measurement of ejection fraction is based upon tracing the left ventricular borders and calculating left ventricular volumes using geometric assumptions. Now, with the introduction of three-dimensional echocardiography, the evaluation of left ventricular function is easier to carry out and with superior accuracy and reproducibility. However, regional myocardial function is mo...

  6. Function and mechanics of the left ventricle: from tissue Doppler imaging to three dimensional speckle tracking

    OpenAIRE

    Arias-Godínez,José Antonio; Guadalajara-Boo,José Fernando; Patel,Ayan R.; Pandian, Natesa G

    2011-01-01

    One of the most common indications in echocardiography is the evaluation of left ventricular function. The traditional measurement of ejection fraction is based upon tracing the left ventricular borders and calculating left ventricular volumes using geometric assumptions. Now, with the introduction of three-dimensional echocardiography, the evaluation of left ventricular function is easier to carry out and with superior accuracy and reproducibility. However, regional myocardial function is mo...

  7. Comparision between thecolor-changed on bull′s-eye plot and global strain of three-dimensional speckle tracking echocardiography for diagnosis coronary artery stenosis%三维斑点追踪牛眼图颜色改变与整体应变诊断冠脉多支病变临床应用价值的研究

    Institute of Scientific and Technical Information of China (English)

    龚晓萍; 李艳红; 穆玉明; 吴治胜

    2016-01-01

    目的:探讨三维斑点追踪(3-dimensional speckle tracking echocardiography,3D-STE )牛眼图颜色改变和整体应变诊断冠脉多支病变的超声心动图特点及其临床应用价值。方法根据冠脉造影的结果,将117例受检者分为冠脉多支组(45例)、单支组(32例)、对照组(40例)。所有受检者行常规经胸二维和三维超声心动图检查,应用3D-STE技术自动生成17节段牛眼图:长轴(LS)、周向(CS)、面积(AS)及径向(RS)应变牛眼图。计算牛眼图中颜色改变节段数,记录左室整体长轴(GLS)、周向(GCS)、面积(GAS)和径向应变(GRS),分析其诊断冠脉多支病变临床应用价值。结果与对照组相比,多支组及单支组牛眼图颜色改变节段数4个参数增多,差异有统计学意义(P <0.05),且多支组增多更明显;多支组整体应变4个参数低于对照组,差异有统计学意义(P <0.05)。与单支组比较,多支组牛眼图颜色改变节段数4个参数增多,但仅周向和面积应变差异有统计学意义(P <0.05)。多支组整体应变4个参数均减低,但差异无统计学意义。ROC分析显示三维斑点追踪牛眼图面积应变诊断冠脉多支病变的灵敏度(86.7%)和特异度(87.5%)最高;整体长轴应变的灵敏度最高(68.9%),整体面积应变的特异度最高(77.5%)。结论三维斑点追踪牛眼图颜色改变节段数与整体应变均能较好地评价冠脉多支病变,而牛眼图颜色改变节段数灵敏度和特异度更高。%Objective To analyze the color-changed on bull′s-eye plot and global strain of three-dimensional speckle tracking echocardiography and to assess the value in the detection n of coronary stenosis.Methods A total of 1 1 7 consecutive patients were enrolled and divided into the following three groups according to the coronary angiography (CAG

  8. Application of real-time three-dimensional transesphaogeal echocardiography in quantitation of tricuspid valve annulus diameter%经食管实时三维超声心动图对三尖瓣环径测量位点的研究

    Institute of Scientific and Technical Information of China (English)

    孔令秋; 康彧; 唐红; 张尔永; 肖锡俊; 郭应强; 宋海波

    2013-01-01

    Objective To verify the feasibility and accuracy in the measurement of tricuspid valve annulus diameter(TVD) in the right ventricular outflow tract view.Methods Seventy five patients under the valve replacement surgery for the left heart valve lesions were divided into mild,moderate and severe group according to the severity of the regurgitation.The TVD was get on the apical four-chamber heart viewpreoperatively by transthoracic echocardiography(TTE),noted as TTE-TVD,meanwhile it was also get by the transesophageal echocardiography on the four-chamber view (TEE-TVD),right ventricular inflow (RVIT-TVD) and outflow tract view(RVOT-TVD).The changes of tricuspid regurgitation severtity was observed preoperatively.And the morphology of tricuspid annulus were observed using both real-time three dimensional transesophageal echocardiography (RT-3D TEE) and the quantitative software.Results Comparison in the groups:no statistically significant difference (P >0.05) was found between TTE-TVD,TEE-TVD and RVIT-TVD;while the RVOT-TVD was significant greater than that in the same group from other views (P < 0.05).Comparison between the groups:no significant difference was found between mild and moderate regurgitation group on the same view.There was a significant difference of the TVD between the severe regurgitation group and the former two groups on each view(P <0.05).The severity of tricuspid regurgitation in intraoperative anesthesia was reduced.The "saddle" tricuspid ring evolved into the narrow planar structure on the RT-3D TEE.For the expansion of the annulus,it departure from the tricuspid septal leaflet.Conclusions TVD measured on the right ventricular outflow tract view reflect the maximum expansion of the tricuspid valve annulus diameter,and can effectively guide the decision-making choices of the surgeon.%目的 探讨在右室流出道切面测量三尖瓣环径(TVD)的可行性与准确性.方法 75例因左心瓣膜损害而行瓣膜置换术患者,根据

  9. Recent advances in echocardiography for valvular heart disease.

    Science.gov (United States)

    Hahn, Rebecca

    2015-01-01

    Echocardiography is the imaging modality of choice for the assessment of patients with valvular heart disease. Echocardiographic advancements may have particular impact on the assessment and management of patients with valvular heart disease. This review will summarize the current literature on advancements, such as three-dimensional echocardiography, strain imaging, intracardiac echocardiography, and fusion imaging, in this patient population.

  10. True three-dimensional camera

    Science.gov (United States)

    Kornreich, Philipp; Farell, Bart

    2013-01-01

    An imager that can measure the distance from each pixel to the point on the object that is in focus at the pixel is described. This is accomplished by short photo-conducting lightguides at each pixel. In the eye the rods and cones are the fiber-like lightguides. The device uses ambient light that is only coherent in spherical shell-shaped light packets of thickness of one coherence length. Modern semiconductor technology permits the construction of lightguides shorter than a coherence length of ambient light. Each of the frequency components of the broad band light arriving at a pixel has a phase proportional to the distance from an object point to its image pixel. Light frequency components in the packet arriving at a pixel through a convex lens add constructively only if the light comes from the object point in focus at this pixel. The light in packets from all other object points cancels. Thus the pixel receives light from one object point only. The lightguide has contacts along its length. The lightguide charge carriers are generated by the light patterns. These light patterns, and thus the photocurrent, shift in response to the phase of the input signal. Thus, the photocurrent is a function of the distance from the pixel to its object point. Applications include autonomous vehicle navigation and robotic vision. Another application is a crude teleportation system consisting of a camera and a three-dimensional printer at a remote location.

  11. Three-dimensional IC trends

    Energy Technology Data Exchange (ETDEWEB)

    Akasaka, Y.

    1986-12-01

    VLSI will be reaching to the limit of minimization in the 1990s, and after that, further increase of packing density or functions might depend on the vertical integration technology. Three-dimensional (3-D) integration is expected to provide several advantages, such as 1) parallel processing, 2) high-speed operation, 3) high packing density, and 4) multifunctional operation. Basic technologies of 3-D IC are to fabricate SOI layers and to stack them monolithically. Crystallinity of the recrystallized layer in SOI has increasingly become better, and very recently crystal-axis controlled, defect-free single-crystal areas has been obtained in chip size level by laser recystallization technology. Some basic functional models showing the concept or image of a future 3-D IC were fabricated in two or three stacked active layers. Some other proposals of subsystems in the application of 3-D structure, and the technical issues for realizing practical 3-D IC, i.e., the technology for fabricating high-quality SOI crystal on complicated surface topology, crosstalk of the signals between the stacked layers, total power consumption and cooling of the chip, are also discussed in this paper.

  12. Three-dimensional colloidal lithography.

    Science.gov (United States)

    Nagai, Hironori; Poteet, Austen; Zhang, Xu A; Chang, Chih-Hao

    2017-03-24

    Light interactions with colloidal particles can generate a variety of complex three-dimensional (3D) intensity patterns, which can be utilized for nanolithography. The study of particle-light interactions can add more types of intensity patterns by manipulating key factors. Here we investigate a novel 3D nanolithography technique using colloidal particles under two-beam coherent illuminations. The fabricated 3D nanostructures are hollow, nested within periodic structures, and possess multiple chamber geometry. The effects of incident angles and particle size on the fabricated nanostructures were examined. The relative phase shift between particle position and interference pattern is identified as another significant parameter influencing the resultant nanostructures. A numerical model has been developed to show the evolution of nanostructure geometry with phase shifts, and experimental studies confirm the simulation results. Through the introduction of single colloidal particles, the fabrication capability of Lloyd's mirror interference can now be extended to fabrication of 3D nanostructure with complex shell geometry. The fabricated hollow nanostructures with grating background could find potential applications in the area of photonics, drug delivery, and nanofluidics.

  13. Three dimensional magnetic abacus memory

    Science.gov (United States)

    Zhang, Shilei; Zhang, Jingyan; Baker, Alexander; Wang, Shouguo; Yu, Guanghua; Hesjedal, Thorsten

    2015-03-01

    Stacking nonvolatile memory cells into a three-dimensional matrix represents a powerful solution for the future of magnetic memory. However, it is technologically challenging to access the individual data in the storage medium if large numbers of bits are stacked on top of each other. Here we introduce a new type of multilevel, nonvolatile magnetic memory concept, the magnetic abacus. Instead of storing information in individual magnetic layers, thereby having to read out each magnetic layer separately, the magnetic abacus adopts a new encoding scheme which envisages a classical abacus with the beads operated by electron spins. It is inspired by the idea of second quantization, dealing with the memory state of the entire stack simultaneously. Direct read operations are implemented by measuring the artificially engineered `quantized' Hall voltage, representing a count of the spin-up and spin-down layers in the stack. This concept of `second quantization of memory' realizes the 3D memory architecture with superior reading and operation efficiency, thus is a promising approach for future nonvolatile magnetic random access memory.

  14. Three-dimensional colloidal lithography

    Science.gov (United States)

    Nagai, Hironori; Poteet, Austen; Zhang, Xu A.; Chang, Chih-Hao

    2017-03-01

    Light interactions with colloidal particles can generate a variety of complex three-dimensional (3D) intensity patterns, which can be utilized for nanolithography. The study of particle–light interactions can add more types of intensity patterns by manipulating key factors. Here we investigate a novel 3D nanolithography technique using colloidal particles under two-beam coherent illuminations. The fabricated 3D nanostructures are hollow, nested within periodic structures, and possess multiple chamber geometry. The effects of incident angles and particle size on the fabricated nanostructures were examined. The relative phase shift between particle position and interference pattern is identified as another significant parameter influencing the resultant nanostructures. A numerical model has been developed to show the evolution of nanostructure geometry with phase shifts, and experimental studies confirm the simulation results. Through the introduction of single colloidal particles, the fabrication capability of Lloyd’s mirror interference can now be extended to fabrication of 3D nanostructure with complex shell geometry. The fabricated hollow nanostructures with grating background could find potential applications in the area of photonics, drug delivery, and nanofluidics.

  15. Change of left ventricular function in peripartum cardiomyopathy after medicine treatment using real-time three-dimensional echocardiography%实时三维超声评价围产期心肌病治疗前后左心室收缩功能的变化

    Institute of Scientific and Technical Information of China (English)

    侯琳琳; 高潮; 史学功; 王邦宁

    2012-01-01

    目的 应用实时三维超声心动图(RT-3DE)对围产期心肌病(peripartum cardiomyopathy,PPCM)患者内科治疗的效果进行评价分析.方法 所有患者均在首次入院后1周内、治疗后3个月,治疗后12个月分别行RT-3DE检查,测量左心室舒张末期容积(LVEDV)、左心室收缩末期容积(LVESV),左心室射血分数(LVEF).结果 治疗后3个月随访LVEDV、LVESV较入院后1周内明显减少,LVEF较入院后1周内明显增加,(123.05±21.77)ml,(79.45±30.97)ml,(45.93±4.28)%vs(141.05±33.20)ml,(97.53±38.57)ml,(37.85±6.28)%.治疗后12个月上述指标较入院后1周内效果亦有明显改善.但较治疗后3个月变化差异无统计学意义.结论 RT-3DE可以准确评估左心室功能.目前药物治疗对于改善PPCM患者心脏形态功能作用有限.%Objective Real-time three-dimensional echocardiography(RT-3DE) was used to evaluate the effect of medicine treatment on peripartum cardiomyopathy(PPCM ). Methods All patients individually underwent RT-3DE soon after one week in first admission in hospital, treatment for three months later and twelve months later. Left ventricular end-diastolic volume (LVEDV),left ventricular end-systolic volume (LVESV) and left ventricular ejection fraction (LVEF) were measured. Results In three months' follow-up, LVEDV and LVESV decreased significantly compared with those measured soon after one week in first admission in hospital, meanwhile LVEF increased significantly,(123. 05 + 21.77) ml, (79. 45 + 30. 97) ml, (45. 93 + 4. 28)% vs (141.05 + 33.20) ml, (97. 53 + 38. 57) ml, (37. 85 + 6. 28) %. In twelve months' follow-up, all the indexes improved significantly compared with those measured soon after one week in first admission in hospital, however all the indexes did not improve significantly compared with those measured three months later. Conclusion RT-3DE was used to evaluate the left ventricular volume and systolic function accurately. The effect of medicine treatment on

  16. Reverse remodeling of left ventricular evaluated by real-time three-dimensional echocardiography in patients with coronary artery bypass graft%实时三维超声心动图评价冠状动脉旁路移植术后患者左心室重构的逆转

    Institute of Scientific and Technical Information of China (English)

    边晓琳; 王雁; 张连仲; 刘琳

    2014-01-01

    Objective To evaluate the clinical application value of reverse remodeling of left ventricular function and synchronism on coronary artery disease( CAD)patients after coronary artery by-pass graft(CABG)using real-time three-dimensional echocardiography(RT-3DE). Methods Left ven-tricular end-diastolic volume( LVEDV),16-segments synchronized indices,peak ejection rate( PER), peak early filling rate(PFR)were measured by RT-3DE in 31 patients with three-vessels of CAD pre-op-eration and post-operation 1 month after CABG. Thirty normal people as control group without coronary stenosis,which were verified by coronary angiography. Results There was significant difference between patients group and control group,LVEDV,Tmsv16-SD and Tmsv16-Dif were significantly increased( P﹤0. 01)in patients group,left ventricular ejection fraction( LVEF),PER and PFR were significantly de-creased(P﹤0. 01)in patients group. There was significant difference between pre-operation and post-op-eration 1 month,LVEDV,Tmsv16-SD and Tmsv16-Dif were significantly decreased in post-operation group,LVEF,PER and PFR were significantly increased( P﹤0. 01 )in post-operation group. Conclu-sions Left ventricular remodeling is induced by three-vessels lesion in patients with CAD. CABG can reverse left ventricular remodeling. The left ventricular reverse remodeling can be evaluated by RT3DE in CAD after CABG.%目的:探讨实时三维超声心动图技术评价冠心病患者冠状动脉旁路移植术后左室收缩功能和同步性逆转的应用价值。方法经选择性冠状动脉造影证实为三支冠状动脉病变的31例冠心病患者,应用实时三维超声心动图于术前及术后1个月测量左心室舒张末期容积(LVEDV)、峰值射血率(PER)、峰值充盈率(PFR)、16节段达峰时间的标准差(Tmsv16-SD)和最大时间差(Tmsv16-Dif),与30例冠状动脉正常的受检者对比分析。结果与对照组相比,病例组LVEDV、Tmsv16-SD

  17. Quantitative evaluation of left ventricular global systolic function in patients with myocardial infarction by three-dimensional speckle tracking echocardiography%超声三维斑点追踪成像评价心肌梗死患者左心室整体收缩功能的研究

    Institute of Scientific and Technical Information of China (English)

    王丁; 邓又斌; 黄润青

    2012-01-01

    Objective To evaluate the value and characteristics of left ventricular global systolic strain and its relation to the left ventricular global systolic function in patients with myocardial infarction(MI) by three-dimensional speckle tracking echocardiography (3D-STI).Methods In 24 patient subjects and 20 control subjects,the myocardial motion was tracking by 3D-STI,left ventricular ejection fraction(LVEF),and global longitudinal peak systolic strain(LVGLS),global circular peak systolic strain(LVGCS),global radial peak systolic strain(LVGRS),global area peak systolic strain(LVGAS) were measured.The values were compared between the two groups,the correlations between LVEF and LVGLS,LVGCS,LVGRS,LVGAS were analyzed respectively.Results (1)There was significant difference of each index about LVEF and global strain between normal group and MI group (all P <0.05).(2)The correlations among LVEF and LVGLS,LVGCS,LVGRS,LVGAS were found (r =-0.626,-0.770,0.772,-0.748 respectively,P <0.01 for all).(3) Bland-Altman analysis showed there were good agreements in both patients with MI and control subjects.Conclusions 3D-STI could be applied non-invisibly and objective to assess alteration of myocardial global systolic function by accurately measuring strain.Therefore,3D-STI appears to be a reliable and useful tool to estimate the left ventricular systolic function of MI.%目的 应用超声三维斑点追踪技术评价心肌梗死患者的左室整体应变特征及与左室整体收缩功能的相关性.方法 使用三维斑点追踪技术对24例心肌梗死患者及20例正常人进行心肌运动分析,测量左室射血分数(LVEF),左室整体纵向、圆周、径向及面积收缩期峰值应变,并比较心肌梗死组与正常组之间的各应变指标变化情况及与LVEF的相关性.结果 三维斑点追踪技术测得心肌梗死患者的LVEF及各整体心肌应变参数均较正常组减低(P<0.05).心肌梗死组左室整体纵向、圆周、径向及面

  18. Quantification study of mitral valve with real-time three-dimensional transesophageal echocardiography before mitral valve replacement%实时三维超声心动图对二尖瓣置换术前瓣膜结构的定量研究

    Institute of Scientific and Technical Information of China (English)

    郎瑞; 冯天鹰; 哈斯

    2014-01-01

    目的 应用经食管实时三维超声心动图(RT-3D-TEE)对风湿性二尖瓣关闭不全行置换术的患者进行二尖瓣对合参数的对比研究.方法 风湿性二尖瓣关闭不全患者16例(风湿组;其中合并轻度狭窄者4例),其中男性6例,女性10例;年龄43~ 67岁,平均年龄53.4岁.正常对照组17例,其中男性7例,女性10例;年龄29 ~ 54岁,平均年龄43.1岁.分别行RT-3D-TEE检查并进行二尖瓣定量分析(MVQ).结果 风湿组在体二尖瓣对合面积为(160.69±50.44)mm2,术后离体瓣膜的对合面积为(163.97±59.58) mm2;对照组MVQ在体二尖瓣对合面积为(296.30±37.31) mm2.两组在体二尖瓣对合面积差异有显著统计学意义(t=8.82,P=0.000 00).MVQ所测二尖瓣对合面积与离体对合面积具有良好的相关性(r=0.892,P< 0.01).Altman-Bland绘图分析结果表明,二者具有较好的一致性,两者的差值为-1.73±8.28,95%的置信区间为(-18.04,14.46).风湿组左心室舒张早期及收缩末期瓣膜面积均较对照组增大(P<0.05),对合面积及对合指数减小(P<0.01).结论 RT-3D-TEE可以实时检测二尖瓣的立体结构,MVQ所测二尖瓣对合参数可以较好地反映二尖瓣的实际对合程度,为二尖瓣病变手术方案的制定及术后疗效的预测提供理论依据.%Objective To compare the mitral valve involution parameters in patients before and after mitral valve replacement by rheumatic mitral insufficiency using real-time three-dimensional transesophageal echocardiography(RT-3D-TEE).Methods A total of 16 patients with rheumatic mitral insufficiency(rheumatic group,and 4 cases combined mild stenosis) were enrolled,which included 6 males and 10 females,aged 43-67 years old with mean age of 53.4.The 17 healthy subjects was set as control group,included 7 males and 10 females,aged 29-54 years old with mean age of 43.1.The correlation parameters of mitral leaflets and annulars were obtained by mitral valve quantitative(MVQ) procedure

  19. 实时三维超声心动图评价冠心病患者PCI术前后左室功能及收缩同步性的研究%Study of left ventricular function and systolic synchrony assessed by real-time three-dimensional echocardiography before and after PCI in coronary heart disease patients

    Institute of Scientific and Technical Information of China (English)

    陈宏博; 刘和俊; 汪太平; 史学功; 金朝龙

    2012-01-01

    Objective To evaluate the influence left ventricular function and systolic synchrony assessed by realtime three-dimensional echocardiography( RT-3DE ) before and after percutaneous coronary intervention therapy ( PCI ) in coronary heart disease patients. Methods By using RT-3DE, the three-dimensional parameters were repeatedly measured in thirty-eight patients with PCI treatment as CHD group before operation, 1st week and 3rd month after operation. Twenty-eight nomal subjects were enrolled as control group. The left ventricular end-diastolic volume( LVEDV ), left ventricular end-systolic volume( LVESV ), left ventricular ejection fraction( LVEF ), left ventricular stroke volume ( LVSV ), left ventricular peak ejection rate( PER ), left ventricular peak filling rate ( PFR), the time of minimal systolic volume of 16-segmental standard deviation( Tmsvl6-SD% ) and maximum difference ( Tmsvl6-Dif% ) were analyzed with software. Results Compared with the control group, LVEDV, LVESV,Tmsvl6-SD% ,Tmsvl6-Dif% were significantly higher ( P <0. 01 ), while LVEF, PER/EDV, PFR/EDV were lower ( P < 0. 01 ) in study group befroe operation. Compared with the preoperative group, LVEDV, LVESV, Tmsvl6-SD% , Tmsvl6-Dif% reduced significantly ( P < 0. 05,P < 0. 01 ), while LVEF, PER/EDV, PFR/EDV increased ( P <0. 05 ,P < 0. 01 ) in postoperative group. The bull-eye diagram showed that systolic timing delayed and systolic excursion attenuated in segments reduced significantly with CHD group after the operation. Conclusion Left ventricular remodeling could be found in patients with coronary heart dease and PCI might reverse the left ventricular remodeling somewhat. RT-3DE could be a new corrected valuable method of evaluating left ventricular function and systolic synchrony in patients with CHD before and after PCI.%目的 应用实时三维超声心动图(RT-3DE)评价冠心病患者经皮冠状动脉介入(PCI)治疗术前后左室功能及收缩同步性的影响.方法

  20. 基于三维经食管超声的3D打印模型指导左心耳封堵的可行性研究%Guidance of three-dimensional printing model of left atrial appendage derived from transesophageal echocardiography for left atrial appendage closure

    Institute of Scientific and Technical Information of China (English)

    宋宏宁; 周青; 邓倾; 陈金玲; 张兰; 何发智; 潘一腾; 刘育; 郭瑞强

    2016-01-01

    Objective To investigate the feasibility of three dimensional printing left atrial appendage(LAA) models from three dimensional transesophageal echocardiography (3D-TEE) volume-rendered data and its value for guiding the placement of LAA occlusion device.Methods Ten patients with non-valvular atrial fibrillation (AF) were underwent TEE before LAA occlusion.3D full volume data and routine two dimensional images of the LAA were acquired.The 3D-TEE data were post-processed by grey values inverted imaging and threshold segmentation to create volume rendered images of the LAA in STL format.The cardiac chamber model and the cardiac wall model of the LAA were printed out by 3D printer for the LAA morphology evaluation and measurement.Preoperative rehearsal was carried out on the printed 3D LAA models.Results In all the patients,3D-TEE full volume data of the LAA were successfully reprocessed and printed out.In terms of the LAA morphology classification based on cardiac chamber models there were 5 chicken wing,3 windsock and 2 cauliflower.And there were 4 single-lobed,3 bi-lobed and 3 multi-lobed.The maximal ostium diameter and the depth of the main anchoring lobe were (20.30 ±3.53)mm and (28.26 ± 5.51)mm respectively,which were concordant well with the measurements of 2D-TEE and CT.The LAmbre and the Lefort occlusion device could be implanted into the 3D LAA models for occlusion planning before the procedure.Occlusion success rate was 100%.Conclusions 3D-TEE full volume data is feasible and capable of creating LAA 3D models.3D models of LAA derived from 3D-TEE have promising value in guiding the LAA occlusion procedure.%目的 探讨应用三维经食管超声(3D-TEE)心腔容积成像进行左心耳3D打印的技术可行性及该技术对左心耳封堵的指导价值.方法 10例因非瓣膜性心房颤动进行经导管左心耳封堵患者,术前行经食管超声心动图检查,采集左心耳二维图像及三维容积图像.对三维DICOM数据进行后处理

  1. Evaluation of left atrial function by three-dimensional speckle-tracking echocardiography in heart failure with preserved ejection fraction patients%三维斑点追踪技术对左室射血分数保留心衰患者左房功能的评估价值

    Institute of Scientific and Technical Information of China (English)

    刘峻松; 王晶; 张波; 刘博罕; 吕文青; 徐勇; 智光

    2015-01-01

    目的 应用三维斑点追踪技术(3D-STE)和实时三维超声心动图(RT3DE)评估探讨左室射血分数保留心衰(HFpEF)患者左房功能变化及意义.方法 将43例HFpEF患者根据左房大小分为A组(左房最大容积指数LAVImax< 34 mL/m2)和B组(LAVImax≥34 ml/m2),18例健康者为对照组.应用3 DSTE分析获取左房基底(Basal)、中间(Middle)、房顶(Roof)和整体(Global)的心室收缩期长轴峰值应变(LSs%)与心房收缩前长轴峰值应变(LSa%),结合RT3 DE和多普勒超声参数进行比较分析.结果 左房中部应变参数具满意可重复性(ICC >0.8),A组左房充盈和排空期形变功能减低以中部为主[与对照组相比:MLSs(33 ±6)%与(45±9)%,MLSa(12±3)%与(17±5)%;P<0.05],B组基底和房顶部形变功能也明显降低[与A组和对照组相比:BLSs(18 ±7)%与(25±8)%与(29±8)%,RLSs (24±9)%与(28±8)%与(32±10)%;与对照组相比:BLSa(11±5)%与(14士4)%,RLSa(12±5)%与(15±5)%;P<0.05].HFpEF患者左房僵硬度明显增加,左房充盈扩张分数(LAEI%)和被动射血分数(LAPEF%)明显降低,B组左房主动射血分数(LAAEF%)也显著降低.结论 3D-STE结合RT3DE可有效评估HFpEF左房功能.左房中部应变参数是评估左房功能的理想指标.HFpEF患者左房储备、通道和泵功能均明显降低,存在明显舒张功能不全,这些变化在左房明显增大患者中更为显著.%Objective To evaluate left atrial function changes inheart failure with preserved ejection fraction (HFpEF) patients by three-dimensional speckle-tracking echocardiography (3D-STE) and Real time three-dimensional echocardiograph(RT3DE).Methods 43 HFpEF patients and a control group with 18 healthy subjectswere enrolled.According to left atrial max volume index (LAVImax),patients were grouped as A (LAVImax < 34 ml/m2) and B (LAVImax≥34 ml/m2).3D-STE deformative parameters,left atrial ventricular-systolic longitudinal peak strain (LSs

  2. 实时三维超声和斑点追踪技术对慢性心衰患者左室再同步化治疗的评价%Assessment of the efficacy of cardiac resynchronization therapy using real-time three-dimensional echocardiography and speckle tracking imaging in patients with chronic heart failure

    Institute of Scientific and Technical Information of China (English)

    骆永娟; 关欣; 朱延波

    2016-01-01

    difference (Tmsv-16Dif). STl was used to evaluate the ratios of standard deviation of the time to peak longitudinal radial and circumferential strain to R-R interval (Tls-16SD%, Trs-16SD%,Tcs-16SD%) from the beginning of Q wave of electrocardiography to the point minimal systolic volume of all 16 segments and the maximum time difference. Results The values of LVEDV and LVESV were smaller 3 and 6 months after CRT than those before CRT. The value of LVEF was significantly improved after CRT (P < 0.05). The values of Tmsv-16SD%, Tmsv-16Dif%, Tls-16SD%, Trs-16SD%, Tcs-16SD%and T-Dif%were gradually decreased after CRT (P<0.05). The values of Tmsv-16SD%, Tmsv-16Dif%,Trs-16SD%and Tcs-16SD%were negatively related with LVEF (r=-0.79,-0.82,-0.69 and-0.74(P<0.05). The better consistency was found between RT-3DE and STI methods(Kappa=0.77). Conclusion Re⁃al-time three-dimensional echocardiography and speckle tracking imaging can provide more accurate quantitative informa⁃tion of cardiac resynchronization therapy for assessment of treatment and prognosis in patients with heart failure.

  3. Left ventricular mechanics in isolated mild mitral stenosis: a three dimensional speckle tracking study.

    Science.gov (United States)

    Poyraz, Esra; Öz, Tuğba Kemaloğlu; Zeren, Gönül; Güvenç, Tolga Sinan; Dönmez, Cevdet; Can, Fatma; Güvenç, Rengin Çetin; Dayı, Şennur Ünal

    2017-09-01

    In a fraction of patients with mild mitral stenosis, left ventricular systolic function deteriorates despite the lack of hemodynamic load imposed by the dysfunctioning valve. Neither the predisposing factors nor the earlier changes in left ventricular contractility were understood adequately. In the present study we aimed to evaluate left ventricular mechanics using three-dimensional (3D) speckle tracking echocardiography. A total of 31 patients with mild rheumatic mitral stenosis and 27 healthy controls were enrolled to the study. All subjects included to the study underwent echocardiographic examination to collect data for two- and three-dimensional speckle-tracking based stain, twist angle and torsion measurements. Data was analyzed offline with a echocardiographic data analysis software. Patients with rheumatic mild MS had lower global longitudinal (p < 0.001) circumferential (p = 0.02) and radial (p < 0.01) strain compared to controls, despite ejection fraction was similar for both groups [(p = 0.45) for three dimensional and (p = 0.37) for two dimensional measurement]. While the twist angle was not significantly different between groups (p = 0.11), left ventricular torsion was significantly higher in mitral stenosis group (p = 0.03). All strain values had a weak but significant positive correlation with mitral valve area measured with planimetry. Subclinical left ventricular systolic dysfunction develops at an early stage in rheumatic mitral stenosis. Further work is needed to elucidate patients at risk for developing overt systolic dysfunction.

  4. In vitro development of bovine secondary follicles in two- and three-dimensional culture systems using vascular endothelial growth factor, insulin-like growth factor-1, and growth hormone.

    Science.gov (United States)

    Araújo, V R; Gastal, M O; Wischral, A; Figueiredo, J R; Gastal, E L

    2014-12-01

    The aim of this study was to evaluate the development and estradiol production of isolated bovine secondary follicles in two-dimensional (2D, experiment 1) and three-dimensional (3D using alginate, experiment 2) long-term culture systems in the absence (control group; only α-MEM(+)) or presence of vascular endothelial growth factor (VEGF), insulin-like growth factor-1, or GH alone, or a combination of all. A total of 363 isolated secondary follicles were cultured individually for 32 days at 38.5 °C in 5% CO2 in a humidified incubator with addition of medium (5 μL) every other day. In 2D culture system, follicular growth and antrum formation rates were higher (P 0.05). In summary, this study demonstrated that the benefits of using a certain type of medium supplement depended on the culture system (2D vs. 3D). Vascular endothelial growth factor was an effective supplement for the in vitro culture of bovine secondary follicles when the 2D culture system was used, whereas GH only affected estradiol production using the 3D culture system. This study sheds light on advancements in methodology to facilitate subsequent studies on bovine preantral follicle development.

  5. Inorganic anion-dependent assembly of zero-, one-, two- and three-dimensional Cu(II)/Ag(I) complexes under the guidance of the HSAB theory: Synthesis, structure, and magnetic property

    Science.gov (United States)

    Liu, Yaru; Xing, Zhiyan; Zhang, Xiao; Liang, Guorui

    2017-02-01

    To systematically explore the influence of inorganic anions on building coordination complexes, five novel complexes based on 1-(benzotriazole-1-methyl)-2-propylimidazole (bpmi), [Cu(bpmi)2(Ac)2]·H2O (1), [Cu(bpmi)2(H2O)2]·2NO3·2H2O (2), [Cu(bpmi)(N3)2] (3), [Ag(bpmi)(NO3)] (4) and [Cu3(bpmi)2(SCN)4(DMF)] (5) (Ac-=CH3COO-, DMF=N,N-Dimethylformamide) are synthesized through rationally introducing Cu(II) salts and Ag(I) salt with different inorganic anions. X-ray single-crystal analyses reveal that these complexes show interesting structural features from mononuclear (1), one-dimensional (2 and 3), two-dimensional (4) to three-dimensional (5) under the influence of inorganic anions with different basicities. The structural variation can be explained by the hard-soft-acid-base (HSAB) theory. Magnetic susceptibility measurement indicates that complex 3 exhibits an antiferromagnetic coupling between adjacent Cu(II) ions.

  6. Elastocapillary fabrication of three-dimensional microstructures

    NARCIS (Netherlands)

    Honschoten, van J.W.; Berenschot, J.W.; Ondarcuhu, T.; Sanders, R.G.P.; Sundaram, J.; Elwenspoek, M.; Tas, N.R.

    2010-01-01

    We describe the fabrication of three-dimensional microstructures by means of capillary forces. Using an origami-like technique, planar silicon nitride structures of various geometries are folded to produce three-dimensional objects of 50–100 m. Capillarity is a particularly effective mechanism since

  7. Three-Dimensional Gravity and String Ghosts

    OpenAIRE

    Carlip, S.; Kogan, I. I.

    1991-01-01

    It is known that much of the structure of string theory can be derived from three-dimensional topological field theory and gravity. We show here that, at least for simple topologies, the string diffeomorphism ghosts can also be explained in terms of three-dimensional physics.

  8. Preliminary study of three-dimensional speckle tracking echocardiography in evaluation of left ventricular systolic longitudinal strain in patients with uremia%三维斑点追踪技术评价不同透析时间尿毒症患者左心室心肌纵向应变的初步研究

    Institute of Scientific and Technical Information of China (English)

    沈丽君; 赵博文; 陈冉; 陈斌; 李世岩; 王蓓; 汤富刚

    2013-01-01

    Objective To evaluate the characteristics of left ventricular systolic longitudinal strain in uremic patients and its relationship with dialysis time using three-dimensional speckle tracking echocardiography (3D-STE).Methods Forty-six uremic patients were divided into three groups according dialysis time (ranged 0-5 years):group A (≤1 year),group B (1 year>time ≤3 years),group C (3 years >time≤5 years),group D was control group.The dynamic images of apical four chamber view were displayed and apical full-volume images were obtained and saved in all subjects using a full volume matrix probe.The original data was recorded and was analyzed by using off-line 3DT analysis software (TomTec 4D MV-Assessment).The longitudinal peak systolic strain and 16 segment systolic strains and strain mean value in 16 segment of left ventricular were acquired and compared.Results The peak strain of apical segment was lower than that of the basal segment and the middle segment and it had an increasing trend from the apical segment to the basal segment in three uremia groups.Instead,it had a decreasing trend from the apical segment to the basal segment in control group.But the differences were not statistically significant.The longitudinal peak systolic strain value,16 segment strain value and mean value of 16 segment strain all were lower in three uremic groups than those of control group.Every segment of 16 segment stain value in group A was higher than those of group B and C.There was no difference in every segment between B and C group in addition to basal and middle segment of anterior septum.Conclusions 3D-STE could evaluate the left ventricular systolic function in uremic patients and the cardiac function could be partly protected by regular dialysis treatment.%目的 利用三维斑点追踪技术(3D-STE)评价尿毒症患者左心室心肌整体及节段纵向应变特征,并探讨其左室应变能力与透析时间的关系.方法 将46例透析时间为0~5年的

  9. Two- and three-dimensional computed tomographic anatomy of the enamel, infundibulae and pulp of 126 equine cheek teeth. Part 1: Findings in teeth without macroscopic occlusal or computed tomographic lesions.

    Science.gov (United States)

    Windley, Z; Weller, R; Tremaine, W H; Perkins, J D

    2009-05-01

    Dental disorders are of major clinical importance in equine practice; however, the knowledge of normal dental anatomy, especially that of the pulp remains incomplete. Computed tomography (CT) is being used increasingly in the diagnosis of dental disease, although the normal 2- (2D) and 3-dimensional (3D) CT anatomy has not yet been fully described. To describe the 2D and 3D CT appearance of the enamel, infundibulae and pulp of normal equine cheek teeth. One-hundred-and-twenty-six cadaveric cheek teeth with eruption ages of 0.5-19 years were evaluated; CT scans of each tooth were performed after occlusal surface examination with a dental probe. Three-dimensional reconstructions of the enamel, infundibulae and pulp were created from the CT scans using greyscale thresholding and subsequent polynomial meshing. Each tooth was sectioned coronally or axially into serial slices using a band saw and the sections compared to the corresponding CT images. The CT reconstructions enabled the systematic description of the pulpar anatomy of the mandibular and maxillary cheek teeth in 3D, which has not been described in detail previously. The number of interpulpar communications between pulp horns and the pulpar volume of each tooth was shown to decrease with increasing age. The interpulpar communications of the maxillary cheek teeth were found to be of greater complexity and variety in comparison to their mandibular counterparts. Mandibular and maxillary cheek teeth showed different, but consistent patterns in their pulpar and enamel morphology. The detailed description of the normal 2D and 3D CT appearance of equine cheek teeth provides a reference basis for the diagnosis of dental disease with CT. Additionally, in depth knowledge of the pulpar anatomy of the equine cheek teeth is an essential prerequisite if endodontic therapy is to develop further in the future.

  10. Uterine cervical carcinoma: a comparison of two- and three-dimensional T2-weighted turbo spin-echo MR imaging at 3.0 T for image quality and local-regional staging

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Y.R. [The Catholic University of Korea, Department of Radiology, Seoul St. Mary' s Hospital, College of Medicine, 222, Banpo-daero, Seocho-gu, Seoul (Korea, Republic of); The Catholic University of Korea, Department of Radiology, Incheon St. Mary' s Hospital, College of Medicine, Bupyeong 6-dong, Bupyeong-gu, Incheon (Korea, Republic of); Rha, S.E.; Choi, B.G.; Oh, S.N.; Park, M.Y.; Byun, J.Y. [The Catholic University of Korea, Department of Radiology, Seoul St. Mary' s Hospital, College of Medicine, 222, Banpo-daero, Seocho-gu, Seoul (Korea, Republic of)

    2013-04-15

    To compare three-dimensional (3D) T2-weighted turbo spin-echo (TSE) with multiplanar two-dimensional (2D) T2-weighted TSE for the evaluation of invasive cervical carcinoma. Seventy-five patients with cervical carcinoma underwent MRI of the pelvis at 3.0 T, using both 5-mm-thick multiplanar 2D (total acquisition time = 12 min 25 s) and 1-mm-thick coronal 3D T2-weighted TSE sequences (7 min 20 s). Quantitative analysis of signal-to-noise ratio (SNR) and qualitative analysis of image quality were performed. Local-regional staging was performed in 45 patients who underwent radical hysterectomy. The estimated SNR of cervical carcinoma and the relative tumour contrast were significantly higher on 3D imaging (P < 0.0001). Tumour conspicuity was better with the 3D sequence, but the sharpness of tumour margin was better with the 2D sequence. No significant difference in overall image quality was noted between the two sequences (P = 0.38). There were no significant differences in terms of the diagnostic accuracy, sensitivity, and specificity of parametrial invasion, vaginal invasion, and lymph node metastases. Multiplanar reconstruction 3D T2-weighted imaging is largely equivalent to 2D T2-weighted imaging for overall image quality and staging accuracy of cervical carcinoma with a shorter MR data acquisition, but has limitations with regard to the sharpness of the tumour margin. circle 3D T2-weighted MR sequence is equivalent to 2D for cervical carcinoma staging. (orig.)

  11. Three Dimensional Illustrating--Three-Dimensional Vision and Deception of Sensibility

    Science.gov (United States)

    Szállassy, Noémi; Gánóczy, Anita; Kriska, György

    2009-01-01

    The wide-spread digital photography and computer use gave the opportunity for everyone to make three-dimensional pictures and to make them public. The new opportunities with three-dimensional techniques give chance for the birth of new artistic photographs. We present in detail the biological roots of three-dimensional visualization, the phenomena…

  12. AIRBORNE LIGHT DETECTION AND RANGING (LIDAR DERIVED DEFORMATION FROM THE MW 6.0 24 AUGUST, 2014 SOUTH NAPA EARTHQUAKE ESTIMATED BY TWO AND THREE DIMENSIONAL POINT CLOUD CHANGE DETECTION TECHNIQUES

    Directory of Open Access Journals (Sweden)

    A. W. Lyda

    2016-06-01

    Full Text Available Remote sensing via LiDAR (Light Detection And Ranging has proven extremely useful in both Earth science and hazard related studies. Surveys taken before and after an earthquake for example, can provide decimeter-level, 3D near-field estimates of land deformation that offer better spatial coverage of the near field rupture zone than other geodetic methods (e.g., InSAR, GNSS, or alignment array. In this study, we compare and contrast estimates of deformation obtained from different pre and post-event airborne laser scanning (ALS data sets of the 2014 South Napa Earthquake using two change detection algorithms, Iterative Control Point (ICP and Particle Image Velocimetry (PIV. The ICP algorithm is a closest point based registration algorithm that can iteratively acquire three dimensional deformations from airborne LiDAR data sets. By employing a newly proposed partition scheme, “moving window,” to handle the large spatial scale point cloud over the earthquake rupture area, the ICP process applies a rigid registration of data sets within an overlapped window to enhance the change detection results of the local, spatially varying surface deformation near-fault. The other algorithm, PIV, is a well-established, two dimensional image co-registration and correlation technique developed in fluid mechanics research and later applied to geotechnical studies. Adapted here for an earthquake with little vertical movement, the 3D point cloud is interpolated into a 2D DTM image and horizontal deformation is determined by assessing the cross-correlation of interrogation areas within the images to find the most likely deformation between two areas. Both the PIV process and the ICP algorithm are further benefited by a presented, novel use of urban geodetic markers. Analogous to the persistent scatterer technique employed with differential radar observations, this new LiDAR application exploits a classified point cloud dataset to assist the change detection

  13. Airborne Light Detection and Ranging (lidar) Derived Deformation from the MW 6.0 24 August, 2014 South Napa Earthquake Estimated by Two and Three Dimensional Point Cloud Change Detection Techniques

    Science.gov (United States)

    Lyda, A. W.; Zhang, X.; Glennie, C. L.; Hudnut, K.; Brooks, B. A.

    2016-06-01

    Remote sensing via LiDAR (Light Detection And Ranging) has proven extremely useful in both Earth science and hazard related studies. Surveys taken before and after an earthquake for example, can provide decimeter-level, 3D near-field estimates of land deformation that offer better spatial coverage of the near field rupture zone than other geodetic methods (e.g., InSAR, GNSS, or alignment array). In this study, we compare and contrast estimates of deformation obtained from different pre and post-event airborne laser scanning (ALS) data sets of the 2014 South Napa Earthquake using two change detection algorithms, Iterative Control Point (ICP) and Particle Image Velocimetry (PIV). The ICP algorithm is a closest point based registration algorithm that can iteratively acquire three dimensional deformations from airborne LiDAR data sets. By employing a newly proposed partition scheme, "moving window," to handle the large spatial scale point cloud over the earthquake rupture area, the ICP process applies a rigid registration of data sets within an overlapped window to enhance the change detection results of the local, spatially varying surface deformation near-fault. The other algorithm, PIV, is a well-established, two dimensional image co-registration and correlation technique developed in fluid mechanics research and later applied to geotechnical studies. Adapted here for an earthquake with little vertical movement, the 3D point cloud is interpolated into a 2D DTM image and horizontal deformation is determined by assessing the cross-correlation of interrogation areas within the images to find the most likely deformation between two areas. Both the PIV process and the ICP algorithm are further benefited by a presented, novel use of urban geodetic markers. Analogous to the persistent scatterer technique employed with differential radar observations, this new LiDAR application exploits a classified point cloud dataset to assist the change detection algorithms. Ground

  14. Highly monodisperse bismuth nanoparticles and their three-dimensional superlattices.

    Science.gov (United States)

    Yarema, Maksym; Kovalenko, Maksym V; Hesser, Günter; Talapin, Dmitri V; Heiss, Wolfgang

    2010-11-01

    A simple and reproducible synthesis of highly monodisperse and ligand-protected bismuth nanoparticles (Bi NPs) is reported. The size of the single-crystalline and spherically shaped NPs is controlled between 11 and 22 nm mainly by the reaction temperature. The high uniformity of the NPs allows their self-assembly into long-range-ordered two- and three-dimensional superstructures.

  15. Three-Dimensional Imaging of a Central Venous Dialysis Catheter Related Infected Thrombus

    Directory of Open Access Journals (Sweden)

    Diana Yuan Yng Chiu

    2015-01-01

    Full Text Available Three-dimensional (3D echocardiography is becoming widely available and with novel applications. We report an interesting case of a 68-year-old lady with a central venous thrombosis coincident with both a dialysis catheter infection and a recent pacemaker insertion. Two-dimensional transesophageal echocardiography was unable to delineate whether the thrombosis was involved with the pacemaker wire or due to the tunneled catheter infection. The use of 3D echocardiography was able to produce distinct images aiding diagnosis. This circumvented the need for invasive investigations and inappropriate, high-risk removal of the pacing wire. This case highlights the emerging application of 3D echocardiography in routine nephrology practice.

  16. Three-Dimensional Imaging of a Central Venous Dialysis Catheter Related Infected Thrombus

    Science.gov (United States)

    Chiu, Diana Yuan Yng; Green, Darren; Kalra, Philip A.; Abidin, Nik

    2015-01-01

    Three-dimensional (3D) echocardiography is becoming widely available and with novel applications. We report an interesting case of a 68-year-old lady with a central venous thrombosis coincident with both a dialysis catheter infection and a recent pacemaker insertion. Two-dimensional transesophageal echocardiography was unable to delineate whether the thrombosis was involved with the pacemaker wire or due to the tunneled catheter infection. The use of 3D echocardiography was able to produce distinct images aiding diagnosis. This circumvented the need for invasive investigations and inappropriate, high-risk removal of the pacing wire. This case highlights the emerging application of 3D echocardiography in routine nephrology practice. PMID:26688761

  17. Device fabrication: Three-dimensional printed electronics

    Science.gov (United States)

    Lewis, Jennifer A.; Ahn, Bok Y.

    2015-02-01

    Can three-dimensional printing enable the mass customization of electronic devices? A study that exploits this method to create light-emitting diodes based on 'quantum dots' provides a step towards this goal.

  18. Three-Dimensional Icosahedral Phase Field Quasicrystal

    Science.gov (United States)

    Subramanian, P.; Archer, A. J.; Knobloch, E.; Rucklidge, A. M.

    2016-08-01

    We investigate the formation and stability of icosahedral quasicrystalline structures using a dynamic phase field crystal model. Nonlinear interactions between density waves at two length scales stabilize three-dimensional quasicrystals. We determine the phase diagram and parameter values required for the quasicrystal to be the global minimum free energy state. We demonstrate that traits that promote the formation of two-dimensional quasicrystals are extant in three dimensions, and highlight the characteristics required for three-dimensional soft matter quasicrystal formation.

  19. Three-dimensional imaging modalities in endodontics

    OpenAIRE

    Mao, Teresa; NEELAKANTAN, Prasanna

    2014-01-01

    Recent research in endodontics has highlighted the need for three-dimensional imaging in the clinical arena as well as in research. Three-dimensional imaging using computed tomography (CT) has been used in endodontics over the past decade. Three types of CT scans have been studied in endodontics, namely cone-beam CT, spiral CT, and peripheral quantitative CT. Contemporary endodontics places an emphasis on the use of cone-beam CT for an accurate diagnosis of parameters that cannot be visualize...

  20. Three-dimensional imaging modalities in endodontics

    OpenAIRE

    Mao, Teresa; Neelakantan, Prasanna

    2014-01-01

    Recent research in endodontics has highlighted the need for three-dimensional imaging in the clinical arena as well as in research. Three-dimensional imaging using computed tomography (CT) has been used in endodontics over the past decade. Three types of CT scans have been studied in endodontics, namely cone-beam CT, spiral CT, and peripheral quantitative CT. Contemporary endodontics places an emphasis on the use of cone-beam CT for an accurate diagnosis of parameters that cannot be visualize...

  1. [Stress echocardiography: development and significance].

    Science.gov (United States)

    Attenhofer, C; Ritter, M; Jenni, R

    1994-08-27

    Exercise electrocardiography is still the primary method used in the non-invasive assessment of coronary artery disease. Stress echocardiography is now being increasingly used as a more sensitive adjunct technique to assess ischemia. Ischemia provoked by stress can induce reversible wall motion abnormalities which are disclosed by cross-sectional 2-dimensional echocardiography and standard projections. The types of stress used are physical exercise (bicycle, treadmill), atrial pacing or pharmacologic stimulation. In the latter, the catecholamine dobutamine has emerged as preferable to the vasodilators dipyridamole and adenosine. The diagnostic accuracy of dobutamine stress echocardiography is comparable to that of bicycle or treadmill exercise echocardiography, but dobutamine stress echocardiography is technically simpler and can be performed in patients unable to exercise. Its sensitivity in diagnosing ischemic or viable myocardium is comparable to that of nuclear methods, MRI or PET. In contrast to nuclear methods, stress echocardiography is however free of radiation. In the assessment of patients with coronary artery disease, stress echocardiography has been shown to be valuable for diagnosis, preoperative risk stratification and determination of prognosis. Furthermore, low dose dobutamine echocardiography can be used to detect viable myocardium. Despite these very promising aspects of the method, there are recognized disadvantages and limitations: stress echocardiography is very time-consuming and operator-dependent; its sensitivity correlates strongly with the number of studies performed; analysis of wall motion is performed qualitatively on a purely subjective level, and hence lacks the objectivity of a quantitative approach. These factors emphasize the need for intensive research to render stress echocardiographic analysis more objective. Automatic boundary detection of left ventricular endocardium, color-Doppler-based tissue imaging and three-dimensional

  2. "Hugging sisters": thoracoomphalopagus with anencephaly confirmed by three-dimensional ultrasonography at 9 weeks of gestation.

    Science.gov (United States)

    Shim, Jae-Yoon; Joo, Da-Hye; Won, Hye-Sung; Lee, Pil Ryang; Kim, Ahm

    2011-06-01

    We describe a rare conjoined twinning at 9 weeks of gestation. We compared the results of two- and three-dimensional sonography with autopsy findings after the termination of pregnancy. These results showed a thoracoomphalopagus with a shared heart and visceral organs. Three-dimensional sonography showed anencephaly in one of the embryos. Early and accurate prenatal diagnosis of this type of conjoined twins using three-dimensional sonography is critical for both parental counseling and minimizing maternal morbidity.

  3. Yttrium oxide based three dimensional metamaterials for visible light cloaking

    Science.gov (United States)

    Rai, Pratyush; Kumar, Prashanth S.; Varadan, Vijay K.; Ruffin, Paul; Brantley, Christina; Edwards, Eugene

    2014-04-01

    Metamaterial with negative refractive index is the key phenomenon behind the concept of a cloaking device to hide an object from light in visible spectrum. Metamaterials made of two and three dimensional lattices of periodically placed electromagnetic resonant cells can achieve absorption and propagation of incident electromagnetic radiation as confined electromagnetic fields confined to a waveguide as surface plasmon polaritons, which can be used for shielding an object from in-tune electromagnetic radiation. The periodicity and dimensions of resonant cavity determine the frequency, which are very small as compared to the wavelength of incident light. Till now the phenomena have been demonstrated only for lights in near infrared spectrum. Recent advancements in fabrication techniques have made it possible to fabricate array of three dimensional nanostructures with cross-sections as small as 25 nm that are required for negative refractive index for wavelengths in visible light spectrum of 400-700 nm and for wider view angle. Two types of metamaterial designs, three dimensional concentric split ring and fishnet, are considered. Three dimensional structures consisted of metal-dielectric-metal stacks. The metal is silver and dielectric is yttrium oxide, other than conventional materials such as FR4 and Duroid. High κ dielectric and high refractive index as well as large crystal symmetry of Yttrium oxide has been investigated as encapsulating medium. Dependence of refractive index on wavelength and bandwidth of negative refractive index region are analyzed for application towards cloaking from light in visible spectrum.

  4. Transferring color between three-dimensional objects

    Science.gov (United States)

    Shen, Hui-Liang; Xin, John H.

    2005-04-01

    A framework for transferring image-based color between three-dimensional objects by the use of a dichromatic reflection model is proposed. The framework addresses the following issues: (1) accurate recovery of an implicit geometric coefficient, (2) calculation of body color, (3) color transfer between different illuminants, and (4) segmentation of multicolored regions. The experimental results show that high color accuracy and photorealistic effects of the synthesized images can be achieved. The proposed technique has wide applications in image-based design and visualization of three-dimensional objects.

  5. Two dimensional fermions in three dimensional YM

    CERN Document Server

    Narayanan, R

    2010-01-01

    Dirac fermions in the fundamental representation of $SU(N)$ live on the surface of a cylinder embedded in $R^3$ and interact with a three dimensional $SU(N)$ Yang Mills vector potential preserving a global chiral symmetry at finite $N$. As the circumference of the cylinder is varied from small to large, the chiral symmetry gets spontaneously broken in the infinite $N$ limit at a typical bulk scale. Replacing three dimensional YM by four dimensional YM introduces non-trivial renormalization effects.

  6. Three-Dimensional Robotic Vision System

    Science.gov (United States)

    Nguyen, Thinh V.

    1989-01-01

    Stereoscopy and motion provide clues to outlines of objects. Digital image-processing system acts as "intelligent" automatic machine-vision system by processing views from stereoscopic television cameras into three-dimensional coordinates of moving object in view. Epipolar-line technique used to find corresponding points in stereoscopic views. Robotic vision system analyzes views from two television cameras to detect rigid three-dimensional objects and reconstruct numerically in terms of coordinates of corner points. Stereoscopy and effects of motion on two images complement each other in providing image-analyzing subsystem with clues to natures and locations of principal features.

  7. Three dimensional dynamics of ferromagnetic swimmer

    Energy Technology Data Exchange (ETDEWEB)

    Erglis, K.; Livanovics, R. [Department of Physics, University of Latvia, Zellu 8, Ri-bar ga LV-1002 (Latvia); Cebers, A., E-mail: aceb@tesla.sal.l [Department of Physics, University of Latvia, Zellu 8, Ri-bar ga LV-1002 (Latvia)

    2011-05-15

    It is shown that a flexible ferromagnetic filament self-propels perpendicularly to the AC magnetic field during a limited period of time due to the instability of the planar motion with respect to three dimensional perturbations. The transition from the oscillating U-like shapes to the oscillating S-like shapes is characterized by the calculated Wr number. - Research Highlights: A ferromagnetic filament self-propels perpendicularly to the AC field. During the self-propulsion cycle the filament moves both forward and backward. The self-propulsion stops due to the three dimensional instability. The mechanism of the self-propulsion is similar to that used by some microorganisms.

  8. Three dimensional electrochemical system for neurobiological studies

    DEFF Research Database (Denmark)

    Vazquez, Patricia; Dimaki, Maria; Svendsen, Winnie Edith

    2009-01-01

    In this work we report a novel three dimensional electrode array for electrochemical measurements in neuronal studies. The main advantage of working with these out-of-plane structures is the enhanced sensitivity of the system in terms of measuring electrochemical changes in the environment...

  9. Electron crystallography of three dimensional protein crystals

    NARCIS (Netherlands)

    Georgieva, Dilyana

    2008-01-01

    This thesis describes an investigation of the potential of electron diffraction for studying three dimensional sub-micro-crystals of proteins and pharmaceuticals. A prerequisite for using electron diffraction for structural studies is the predictable availability of tiny crystals. A method for grow

  10. Three dimensional measurement of rhinoplasty results.

    NARCIS (Netherlands)

    Heerbeek, N. van; Ingels, K.J.A.O.; Loon, B. van; Plooij, J.M.; Berge, S.J.

    2009-01-01

    BACKGROUND: Pre- and postoperative imaging is important and essential for evaluation of the results of rhinoplasty surgery. Two-dimensional photographs are used routinely for this purpose, but have several disadvantages as opposed to three-dimensional imaging techniques, such as

  11. Three-dimensional patterning methods and related devices

    Energy Technology Data Exchange (ETDEWEB)

    Putnam, Morgan C.; Kelzenberg, Michael D.; Atwater, Harry A.; Boettcher, Shannon W.; Lewis, Nathan S.; Spurgeon, Joshua M.; Turner-Evans, Daniel B.; Warren, Emily L.

    2016-12-27

    Three-dimensional patterning methods of a three-dimensional microstructure, such as a semiconductor wire array, are described, in conjunction with etching and/or deposition steps to pattern the three-dimensional microstructure.

  12. Comparison between two-dimensional and midsagittal three-dimensional cephalometric measurements of dry human skulls

    NARCIS (Netherlands)

    Damstra, Janalt; Fourie, Zacharias; Ren, Yijin

    2011-01-01

    The aim of this study was to compare two- and three-dimensional cephalometric values by using a three-dimensional analysis based on the midsagittal plane. Spherical metal markers were fixed on to the anatomical landmarks of 10 human skulls, which were examined radiographically with conventional late

  13. Asymmetric Mutualism in Two- and Three-Dimensional Range Expansions

    Science.gov (United States)

    Lavrentovich, Maxim O.; Nelson, David R.

    2014-04-01

    Genetic drift at the frontiers of two-dimensional range expansions of microorganisms can frustrate local cooperation between different genetic variants, demixing the population into distinct sectors. In a biological context, mutualistic or antagonistic interactions will typically be asymmetric between variants. By taking into account both the asymmetry and the interaction strength, we show that the much weaker demixing in three dimensions allows for a mutualistic phase over a much wider range of asymmetric cooperative benefits, with mutualism prevailing for any positive, symmetric benefit. We also demonstrate that expansions with undulating fronts roughen dramatically at the boundaries of the mutualistic phase, with severe consequences for the population genetics along the transition lines.

  14. BioProgrammable One, Two, and Three Dimensional Materials

    Science.gov (United States)

    2017-01-18

    atom/ion and f’ is the dispersive correction term. Rb+ (Z = 36) is ideally suited for ASAXS because its K absorption edge Ek = 15,200 eV is readily...Nikoobakht, B.; El-Sayed, M. A. "Preparation and growth mechanism of gold nanorods (NRs) using seed -mediated growth method," Chem. Mater., 2003, 15 (10...Universal Noble Metal Nanoparticle Seeds Realized Through Iterative Reductive Growth and Oxidative Dissolution Reactions,” JACS, 2014, 136, 7603-7606. 22

  15. Deformations of three-dimensional metrics

    Science.gov (United States)

    Pugliese, Daniela; Stornaiolo, Cosimo

    2015-03-01

    We examine three-dimensional metric deformations based on a tetrad transformation through the action the matrices of scalar field. We describe by this approach to deformation the results obtained by Coll et al. (Gen. Relativ. Gravit. 34:269, 2002), where it is stated that any three-dimensional metric was locally obtained as a deformation of a constant curvature metric parameterized by a 2-form. To this aim, we construct the corresponding deforming matrices and provide their classification according to the properties of the scalar and of the vector used in Coll et al. (Gen Relativ Gravit 34:269, 2002) to deform the initial metric. The resulting causal structure of the deformed geometries is examined, too. Finally we apply our results to a spherically symmetric three geometry and to a space sector of Kerr metric.

  16. THREE DIMENSIONAL GRAPHICAL REPRESENTATION OF QUALITY

    Directory of Open Access Journals (Sweden)

    Vineet V. Kumar

    2014-03-01

    Full Text Available Quality is an important aspect for every firm in modern era of competition. Every product has tough competition in terms of market reach. The factor, which actually makes any product long run in market, is quality and hence quality is the stepping-stone for success of any firm. For everyone meaning of quality is different. We have seen several economists who have defined quality by considering different factors, but what all of them have common in them is Customer satisfaction. Customer satisfaction is the ultimate result of quality. In three-dimensional graphical representation of quality, optimum quality is obtained by using three-dimensional graph by considering some important factors governing quality of any product, limiting factor, and customer satisfaction.

  17. Three-dimensional broadband tunable terahertz metamaterials

    DEFF Research Database (Denmark)

    Fan, Kebin; Strikwerda, Andrew; Zhang, Xin

    2013-01-01

    We present optically tunable magnetic three-dimensional (3D) metamaterials at terahertz (THz) frequencies which exhibit a tuning range of ~30% of the resonance frequency. This is accomplished by fabricating 3D array structures consisting of double-split-ring resonators (DSRRs) on silicon on sapph......We present optically tunable magnetic three-dimensional (3D) metamaterials at terahertz (THz) frequencies which exhibit a tuning range of ~30% of the resonance frequency. This is accomplished by fabricating 3D array structures consisting of double-split-ring resonators (DSRRs) on silicon...... as verified through electromagnetic simulations and parameter retrieval. Our approach extends dynamic metamaterial tuning to magnetic control, and may find applications in switching and modulation, polarization control, or tunable perfect absorbers....

  18. Three-dimensional imaging modalities in endodontics

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Teresa; Neelakantan, Prasanna [Dept. of Conservative Dentistry and Endodontics, Saveetha Dental College and Hospitals, Saveetha University, Chennai (India)

    2014-09-15

    Recent research in endodontics has highlighted the need for three-dimensional imaging in the clinical arena as well as in research. Three-dimensional imaging using computed tomography (CT) has been used in endodontics over the past decade. Three types of CT scans have been studied in endodontics, namely cone-beam CT, spiral CT, and peripheral quantitative CT. Contemporary endodontics places an emphasis on the use of cone-beam CT for an accurate diagnosis of parameters that cannot be visualized on a two-dimensional image. This review discusses the role of CT in endodontics, pertaining to its importance in the diagnosis of root canal anatomy, detection of peri-radicular lesions, diagnosis of trauma and resorption, presurgical assessment, and evaluation of the treatment outcome.

  19. Three-dimensional imaging modalities in endodontics.

    Science.gov (United States)

    Mao, Teresa; Neelakantan, Prasanna

    2014-09-01

    Recent research in endodontics has highlighted the need for three-dimensional imaging in the clinical arena as well as in research. Three-dimensional imaging using computed tomography (CT) has been used in endodontics over the past decade. Three types of CT scans have been studied in endodontics, namely cone-beam CT, spiral CT, and peripheral quantitative CT. Contemporary endodontics places an emphasis on the use of cone-beam CT for an accurate diagnosis of parameters that cannot be visualized on a two-dimensional image. This review discusses the role of CT in endodontics, pertaining to its importance in the diagnosis of root canal anatomy, detection of peri-radicular lesions, diagnosis of trauma and resorption, presurgical assessment, and evaluation of the treatment outcome.

  20. Three-dimensional Imaging, Visualization, and Display

    CERN Document Server

    Javidi, Bahram; Son, Jung-Young

    2009-01-01

    Three-Dimensional Imaging, Visualization, and Display describes recent developments, as well as the prospects and challenges facing 3D imaging, visualization, and display systems and devices. With the rapid advances in electronics, hardware, and software, 3D imaging techniques can now be implemented with commercially available components and can be used for many applications. This volume discusses the state-of-the-art in 3D display and visualization technologies, including binocular, multi-view, holographic, and image reproduction and capture techniques. It also covers 3D optical systems, 3D display instruments, 3D imaging applications, and details several attractive methods for producing 3D moving pictures. This book integrates the background material with new advances and applications in the field, and the available online supplement will include full color videos of 3D display systems. Three-Dimensional Imaging, Visualization, and Display is suitable for electrical engineers, computer scientists, optical e...

  1. Three-Dimensional Printing in Orthopedic Surgery.

    Science.gov (United States)

    Eltorai, Adam E M; Nguyen, Eric; Daniels, Alan H

    2015-11-01

    Three-dimensional (3D) printing is emerging as a clinically promising technology for rapid prototyping of surgically implantable products. With this commercially available technology, computed tomography or magnetic resonance images can be used to create graspable objects from 3D reconstructed images. Models can enhance patients' understanding of their pathology and surgeon preoperative planning. Customized implants and casts can be made to match an individual's anatomy. This review outlines 3D printing, its current applications in orthopedics, and promising future directions.

  2. Lossless compression for three-dimensional images

    Science.gov (United States)

    Tang, Xiaoli; Pearlman, William A.

    2004-01-01

    We investigate and compare the performance of several three-dimensional (3D) embedded wavelet algorithms on lossless 3D image compression. The algorithms are Asymmetric Tree Three-Dimensional Set Partitioning In Hierarchical Trees (AT-3DSPIHT), Three-Dimensional Set Partitioned Embedded bloCK (3D-SPECK), Three-Dimensional Context-Based Embedded Zerotrees of Wavelet coefficients (3D-CB-EZW), and JPEG2000 Part II for multi-component images. Two kinds of images are investigated in our study -- 8-bit CT and MR medical images and 16-bit AVIRIS hyperspectral images. First, the performances by using different size of coding units are compared. It shows that increasing the size of coding unit improves the performance somewhat. Second, the performances by using different integer wavelet transforms are compared for AT-3DSPIHT, 3D-SPECK and 3D-CB-EZW. None of the considered filters always performs the best for all data sets and algorithms. At last, we compare the different lossless compression algorithms by applying integer wavelet transform on the entire image volumes. For 8-bit medical image volumes, AT-3DSPIHT performs the best almost all the time, achieving average of 12% decreases in file size compared with JPEG2000 multi-component, the second performer. For 16-bit hyperspectral images, AT-3DSPIHT always performs the best, yielding average 5.8% and 8.9% decreases in file size compared with 3D-SPECK and JPEG2000 multi-component, respectively. Two 2D compression algorithms, JPEG2000 and UNIX zip, are also included for reference, and all 3D algorithms perform much better than 2D algorithms.

  3. Three-dimensional display of document set

    Energy Technology Data Exchange (ETDEWEB)

    Lantrip, David B [Oxnard, CA; Pennock, Kelly A [Richland, WA; Pottier, Marc C [Richland, WA; Schur, Anne [Richland, WA; Thomas, James J [Richland, WA; Wise, James A [Richland, WA; York, Jeremy [Bothell, WA

    2009-06-30

    A method for spatializing text content for enhanced visual browsing and analysis. The invention is applied to large text document corpora such as digital libraries, regulations and procedures, archived reports, and the like. The text content from these sources may be transformed to a spatial representation that preserves informational characteristics from the documents. The three-dimensional representation may then be visually browsed and analyzed in ways that avoid language processing and that reduce the analysts' effort.

  4. Three-dimensional display of document set

    Energy Technology Data Exchange (ETDEWEB)

    Lantrip, David B. (Oxnard, CA); Pennock, Kelly A. (Richland, WA); Pottier, Marc C. (Richland, WA); Schur, Anne (Richland, WA); Thomas, James J. (Richland, WA); Wise, James A. (Richland, WA)

    2006-09-26

    A method for spatializing text content for enhanced visual browsing and analysis. The invention is applied to large text document corpora such as digital libraries, regulations and procedures, archived reports, and the like. The text content from these sources may e transformed to a spatial representation that preserves informational characteristics from the documents. The three-dimensional representation may then be visually browsed and analyzed in ways that avoid language processing and that reduce the analysts' effort.

  5. Three-Dimensional Dispaly Of Document Set

    Energy Technology Data Exchange (ETDEWEB)

    Lantrip, David B. (Oxnard, CA); Pennock, Kelly A. (Richland, WA); Pottier, Marc C. (Richland, WA); Schur, Anne (Richland, WA); Thomas, James J. (Richland, WA); Wise, James A. (Richland, WA)

    2003-06-24

    A method for spatializing text content for enhanced visual browsing and analysis. The invention is applied to large text document corpora such as digital libraries, regulations and procedures, archived reports, and the like. The text content from these sources may be transformed to a spatial representation that preserves informational characteristics from the documents. The three-dimensional representation may then be visually browsed and analyzed in ways that avoid language processing and that reduce the analysts' effort.

  6. Three-dimensional display of document set

    Energy Technology Data Exchange (ETDEWEB)

    Lantrip, David B [Oxnard, CA; Pennock, Kelly A [Richland, WA; Pottier, Marc C [Richland, WA; Schur, Anne [Richland, WA; Thomas, James J [Richland, WA; Wise, James A [Richland, WA

    2001-10-02

    A method for spatializing text content for enhanced visual browsing and analysis. The invention is applied to large text document corpora such as digital libraries, regulations and procedures, archived reports, and the like. The text content from these sources may be transformed to a spatial representation that preserves informational characteristics from the documents. The three-dimensional representation may then be visually browsed and analyzed in ways that avoid language processing and that reduce the analysts' effort.

  7. Three-Dimensional Ocean Noise Modeling

    Science.gov (United States)

    2015-03-01

    particular attention paid to the case of Gaussian canyon . The solution to the three-dimensional wave equation in Cartesian co-ordinates can be written...in terms of a modal decomposition, carried out in the vertical and across- canyon horizontal directions. Work Completed 1. Nx2D and 3D Noise PE...azimuth in the Hudson Canyon [Figure 2). Additionally, the PE-reciprocity noise model was used to estimate the size, speed and distance from the

  8. Three dimensional boundary layers in internal flows

    Science.gov (United States)

    Bodonyi, R. J.

    1987-01-01

    A numerical study of the effects of viscous-inviscid interactions in three-dimensional duct flows is presented. In particular interacting flows for which the oncoming flow is not fully-developed were considered. In this case there is a thin boundary layer still present upstream of the surface distortion, as opposed to the fully-developed pipe flow situation wherein the flow is viscous across the cross section.

  9. Multiparallel Three-Dimensional Optical Microscopy

    Science.gov (United States)

    Nguyen, Lam K.; Price, Jeffrey H.; Kellner, Albert L.; Bravo-Zanoquera, Miguel

    2010-01-01

    Multiparallel three-dimensional optical microscopy is a method of forming an approximate three-dimensional image of a microscope sample as a collection of images from different depths through the sample. The imaging apparatus includes a single microscope plus an assembly of beam splitters and mirrors that divide the output of the microscope into multiple channels. An imaging array of photodetectors in each channel is located at a different distance along the optical path from the microscope, corresponding to a focal plane at a different depth within the sample. The optical path leading to each photodetector array also includes lenses to compensate for the variation of magnification with distance so that the images ultimately formed on all the photodetector arrays are of the same magnification. The use of optical components common to multiple channels in a simple geometry makes it possible to obtain high light-transmission efficiency with an optically and mechanically simple assembly. In addition, because images can be read out simultaneously from all the photodetector arrays, the apparatus can support three-dimensional imaging at a high scanning rate.

  10. Imaging unsteady three-dimensional transport phenomena

    Indian Academy of Sciences (India)

    K Muralidhar

    2014-01-01

    Careful and continuous measurements of flow, heat and mass transfer are required in quite a few contexts. Using appropriate light sources, it is possible to map velocity, temperature, and species concentration over a cross-section and as a function of time. Image formation in optical measurements may rely on scattering of radiation from particles. Alternatively, if the region of interest is transparent, refractive index would be a field variable and beam bending effects can be used to extract information about temperature and concentration of solutes dissolved in liquids. Time-lapsed images of light intensity can be used to determine fluid velocity. Though used originally for flow visualization, optical imaging has now emerged as a powerful tool for quantitative measurements. Optical methods that utilize the dependence of refractive index on concentration and temperature can be configured in many different ways. Three available routes considered are interferometry, schlieren imaging, and shadowgraph. Images recorded in these configurations can be analysed to yield time sequences of three-dimensional distributions of the transported variables. Optical methods are non-intrusive, inertia-free and can image cross-sections of the experimental apparatus. The image data can be jointly analysed with the physical laws governing transport and principles of image formation. Hence, with the experiment suitably carried out, three-dimensional physical domains with unsteady processes can be accommodated. Optical methods promise to breach the holy grail of measurements by extracting unsteady three-dimensional data in applications related to transport phenomena.

  11. Volumetric Three-Dimensional Display Systems

    Science.gov (United States)

    Blundell, Barry G.; Schwarz, Adam J.

    2000-03-01

    A comprehensive study of approaches to three-dimensional visualization by volumetric display systems This groundbreaking volume provides an unbiased and in-depth discussion on a broad range of volumetric three-dimensional display systems. It examines the history, development, design, and future of these displays, and considers their potential for application to key areas in which visualization plays a major role. Drawing substantially on material that was previously unpublished or available only in patent form, the authors establish the first comprehensive technical and mathematical formalization of the field, and examine a number of different volumetric architectures. System level design strategies are presented, from which proposals for the next generation of high-definition predictable volumetric systems are developed. To ensure that researchers will benefit from work already completed, they provide: * Descriptions of several recent volumetric display systems prepared from material supplied by the teams that created them * An abstract volumetric display system design paradigm * An historical summary of 90 years of development in volumetric display system technology * An assessment of the strengths and weaknesses of many of the systems proposed to date * A unified presentation of the underlying principles of volumetric display systems * A comprehensive bibliography Beautifully supplemented with 17 color plates that illustrate volumetric images and prototype displays, Volumetric Three-Dimensional Display Systems is an indispensable resource for professionals in imaging systems development, scientific visualization, medical imaging, computer graphics, aerospace, military planning, and CAD/CAE.

  12. Three dimensional illustrating - three-dimensional vision and deception of sensibility

    Directory of Open Access Journals (Sweden)

    Anita Gánóczy

    2009-03-01

    Full Text Available The wide-spread digital photography and computer use gave the opportunity for everyone to make three-dimensional pictures and to make them public. The new opportunities with three-dimensional techniques give chance for the birth of new artistic photographs. We present in detail the biological roots of three-dimensional visualization, the phenomena of movement parallax, which can be used efficiently in making three-dimensional graphics, the Zöllner- and Corridor-illusion. There are present in this paper the visual elements, which contribute to define a plane two-dimensional image in three-dimension: coherent lines, the covering, the measurement changes, the relative altitude state, the abatement of detail profusion, the shadings and the perspective effects of colors.

  13. Three-dimensional analysis of craniofacial bones using three-dimensional computer tomography

    Energy Technology Data Exchange (ETDEWEB)

    Ono, Ichiro; Ohura, Takehiko; Kimura, Chu (Hokkaido Univ., Sapporo (Japan). School of Medicine) (and others)

    1989-08-01

    Three-dimensional computer tomography (3DCT) was performed in patients with various diseases to visualize stereoscopically the deformity of the craniofacial bones. The data obtained were analyzed by the 3DCT analyzing system. A new coordinate system was established using the median sagittal plane of the face (a plane passing through sella, nasion and basion) on the three-dimensional image. Three-dimensional profilograms were prepared for detailed analysis of the deformation of craniofacial bones for cleft lip and palate, mandibular prognathia and hemifacial microsomia. For patients, asymmetry in the frontal view and twist-formed complicated deformities were observed, as well as deformity of profiles in the anteroposterior and up-and-down directions. A newly developed technique allows three-dimensional visualization of changes in craniofacial deformity. It would aid in determining surgical strategy, including crani-facial surgery and maxillo-facial surgery, and in evaluating surgical outcome. (N.K.).

  14. Stress echocardiography

    NARCIS (Netherlands)

    A. Salustri (Alessandro)

    1993-01-01

    textabstractIn the studies reported in this thesis, stress echocardiography (either with exercise or with pharmacological agents) and myocardial perfusion scintigraphy have been performed in different groups of patients and in different clinical conditions. Some practical aspects on the protocols of

  15. Stress echocardiography

    NARCIS (Netherlands)

    A. Salustri (Alessandro)

    1993-01-01

    textabstractIn the studies reported in this thesis, stress echocardiography (either with exercise or with pharmacological agents) and myocardial perfusion scintigraphy have been performed in different groups of patients and in different clinical conditions. Some practical aspects on the protocols

  16. Stability of three-dimensional boundary layers

    Science.gov (United States)

    Nayfeh, A. H.

    1979-01-01

    A theory is presented for the three-dimensional stability of boundary layers. Equations are derived for the evolution of a disturbance having a given frequency and originating at a given curve. These equations are used to determine the rays along which the disturbance energy propagates. It is shown that the results can be obtained by using the saddle-point method, or kinematic wave theory, or the method of multiple scales. Extension of the theory to the case of a wave packet is also presented.

  17. Nonparallel stability of three-dimensional flows

    Science.gov (United States)

    Padhye, A. R.; Nayfeh, A. H.

    1981-01-01

    The linear stability of three-dimensional incompressible, isothermal, nonparallel boundary-layer flows has been investigated. The method of multiple scales is used to derive the partial-differential equations that describe the spatial modulations of the amplitude, phase and wavenumber of a disturbance. Group velocities are used to determine the disturbance growth direction. The envelope method is used to calculate the logarithmic amplitude growth rate N. The theory is applied to the flows over a swept-back tapered wing with boundary-layer suction. Results of such analysis for the X-21 wing are discussed. It is found that the nonparallel effects for this wing is substantial.

  18. Stabilization of Three-Dimensional Collective Motion

    CERN Document Server

    Scardovi, Luca; Sepulchre, Rodolphe

    2008-01-01

    This paper proposes a methodology to stabilize relative equilibria in a model of identical, steered particles moving in three-dimensional Euclidean space. Exploiting the Lie group structure of the resulting dynamical system, the stabilization problem is reduced to a consensus problem on the Lie algebra. The resulting equilibria correspond to parallel, circular and helical formations. We first derive the stabilizing control laws in the presence of all-to-all communication. Providing each agent with a consensus estimator, we then extend the results to a general setting that allows for unidirectional and time-varying communication topologies.

  19. Three-dimensional cooling of muons

    CERN Document Server

    Vsevolozhskaya, T A

    2000-01-01

    The simultaneous ionization cooling of muon beams in all three - the longitudinal and two transverse - directions is considered in a scheme, based on bent lithium lenses with dipole constituent of magnetic field in them, created by a special configuration of current-carrying rod. An analysis of three-dimensional cooling is performed with the use of kinetic equation method. Results of numerical calculation for a specific beam line configuration are presented together with results of computer simulation using the Moliere distribution to describe the Coulomb scattering and the Vavilov distribution used to describe the ionization loss of energy.

  20. Three dimensional dilatonic gravity's rainbow: exact solutions

    CERN Document Server

    Hendi, Seyed Hossein; Panahiyan, Shahram

    2016-01-01

    Deep relations of dark energy scenario and string theory results with dilaton gravity, on one hand, and the connection between quantum gravity with gravity's rainbow, on the other hand, motivate us to consider three dimensional dilatonic black hole solutions in gravity's rainbow. We obtain two classes of the solutions which are polynomial and logarithmic forms. We also calculate conserved and thermodynamic quantities, and examine the first law of thermodynamics for both classes. In addition, we study thermal stability and show that one of the classes is thermally stable while the other one is unstable.

  1. Recent advances in echocardiography for nuclear medicine physician

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Geu Ru; Shin, Dong Gu [Yeungnam University College of Medicine, Daegu (Korea, Republic of)

    2005-10-15

    Echocardiography is one of the most frequently used techniques for diagnosing cardiovascular diseases. Over the last twenty years, technological advances have enabled the application of high-quality imaging. Important recent developments have occurred in echocardiography that are already being used clinically. Equipment and hardware is now available to produce real time three-dimensional and contrast enhanced imaging. Tissue Doppler and stress echocardiography have provided potential benefit to analyze hemodynamic information of heart. This review discusses each of these new developments and their potential impact on the practice of echocardiography and cardiology in general.

  2. Assessment of left ventricular global systolic and diastolic function using volume-time curves by real-time three-dimensional echocardiography%实时三维超声心动图容积时间曲线评价左心室整体收缩和舒张功能

    Institute of Scientific and Technical Information of China (English)

    魏常华; 袁建军; 苑淑姣

    2008-01-01

    Objective To quantitatively assess left ventricular global systolic and diastolic function using volume-time curves (VTC) by real-time three-dimensional echoeardiography(RT-3DE).Methods Ninty-eight subjects were divided into four groups.Group A consisted of twenty-eight normal subject,group B included twenty-four patients with hypertensive(HTN), group C consisted of twenty-four patients with coronary artery disease(CAD) and group D of twenty-two patients having dilated cordiomyopathy (DCM).Participants were selected undergoing full volume RT-3DE.The global and 17-segmental VTCs were obtained by the off-line Qlab software.The end-diastolic volume(EDV), end-systolic volume(ESV) and ejection fraction(EF) were derived from VTCs.The peak ejection rate(PER),peak early filling rate (PFR),PER/EDV and PFR/EDV were calculted.Results EDV and ESV of group B,C and D was significantly larger than that of group A(all P < 0.05), EF and PER/EDV of group C and D significantly lower than those of group A.There were close correlation between PER/EDV and EF ( r=0.694, P<0.05).Comparison of VTC pattern of HTN,CAD and DCM with that of healthy participants revealed the loss of symmetry of systolic and diastolic pattern.Conclusions Generation of VTCs by RT3DE is a promising approach to evaluate left ventricular global systolic and diastolic function.PER/EDV and PFR/EDV may be potential parameters for assessing left ventricular global systolic and diastolic function.%目的 应用实时三维超声心动图(RT-3DE)容积-时间曲线(VTC)定量评价左心室整体收缩和舒张功能.方法 98例研究对象分为4组:A组,正常人28例;B组,高血压病患者24例;C组,冠心病患者24例;D组,扩张性心肌病22例.对所有研究对象进行RT-3DE检查,采集全容积三维图像,应用Qlab分析软件对三维数据库进行分析,得到左室整体和17节段容积时间曲线,测量舒张末容积(EDV)、收缩末容积(ESV)和左室射血分数(EF),并计算峰值射血

  3. The Application of Real-time Three-dimensional Tansesophageal Echocardiography in Aorta Petal Replacement Technique%经食管实时三维超声心动图在主动脉瓣置换术中的应用

    Institute of Scientific and Technical Information of China (English)

    张瑜; 丁云川; 尹帆; 陈剑; 罗庆祎; 王庆慧

    2013-01-01

    Objective To discuss the clinical practice value of the transesophageal real-time three dimensional echocardiogram (RT-3DTEE) in the aorta petal artificial valve replacement technique. Methods 25 cases of aorta petal replacement technique and 31 cases of bicuspid valve and the aorta petal replacement technique were given RT-3DTEE and the examination results were compared with the results of surgical operation. Results Surgery was successfully performed in 56 cases, and fine RT-3 DTEE images were obtained. Among the 56 cases, 1 case had granulation around artificial valve, artificial aortic valve stenosis and regurgitation, and was given the elimination of periprosthetic granulation and successful re-aortic valve replacement after determining the location of granulation by RT-3 DTEE; 1 case were found with the entire artificial mechanical petal and the perivalvular leak and timely treated by RT-3DTEE after cardiac resuscitation. 1 case were found with asynchronous opening of two artificial aorta petal leaves due to the dysfunction of the left ventrium muscle contraction and treated timely after cardiac resuscitation. Conclusion The RT-3DTEE is a direct-viewing, fast and accurate assessment method in the aorta petal replacement technique.%目的 探讨经食管实时三维超声心动图在主动脉瓣人工瓣膜置换术中的临床应用价值.方法 运用经食管实时三维超声心动图对25例主动脉瓣置换术,31例二尖瓣及主动脉瓣置换术患者的主动脉瓣环经(AAD)进行观测,结果与二维AAD测值外科手术中所选机械瓣型号对比.结果 56例患者手术顺利,获得满意RT-3DTEE图像,其中1例患者为瓣周肉芽、人工主动脉瓣狭窄并关闭不全,在RT-3DTEE确定肉芽生长位置,手术彻底清除瓣周肉芽,并成功完成再次主动脉瓣置换术.1例术中心脏复跳后RT-3DTEE发现清晰显示人工机械瓣及瓣周瘘的全貌,进行补救;1例患者心脏复跳后,发现因左室心肌收缩乏

  4. Two component-three dimensional catalysis

    Science.gov (United States)

    Schwartz, Michael; White, James H.; Sammells, Anthony F.

    2002-01-01

    This invention relates to catalytic reactor membranes having a gas-impermeable membrane for transport of oxygen anions. The membrane has an oxidation surface and a reduction surface. The membrane is coated on its oxidation surface with an adherent catalyst layer and is optionally coated on its reduction surface with a catalyst that promotes reduction of an oxygen-containing species (e.g., O.sub.2, NO.sub.2, SO.sub.2, etc.) to generate oxygen anions on the membrane. The reactor has an oxidation zone and a reduction zone separated by the membrane. A component of an oxygen containing gas in the reduction zone is reduced at the membrane and a reduced species in a reactant gas in the oxidation zone of the reactor is oxidized. The reactor optionally contains a three-dimensional catalyst in the oxidation zone. The adherent catalyst layer and the three-dimensional catalyst are selected to promote a desired oxidation reaction, particularly a partial oxidation of a hydrocarbon.

  5. Three-dimensional flow in Kupffer's Vesicle

    CERN Document Server

    Montenegro-Johnson, Thomas D; Smith, David J; Lopes, Susana S

    2016-01-01

    Whilst many vertebrates appear externally left-right symmetric, the arrangement of internal organs is asymmetric. In zebrafish, the breaking of left-right symmetry is organised by Kupffer's Vesicle (KV): an approximately spherical, fluid-filled structure that begins to form in the embryo 10 hours post fertilisation. A crucial component of zebrafish symmetry breaking is the establishment of a cilia-driven fluid flow within KV. However, it is still unclear (a) how dorsal, ventral and equatorial cilia contribute to the global vortical flow, and (b) if this flow breaks left-right symmetry through mechanical transduction or morphogen transport. Fully answering these questions requires knowledge of the three-dimensional flow patterns within KV, which have not been quantified in previous work. In this study, we calculate and analyse the three-dimensional flow in KV. We consider flow from both individual and groups of cilia, and (a) find anticlockwise flow can arise purely from excess of cilia on the dorsal roof over...

  6. Three dimensional force balance of asymmetric droplets

    Science.gov (United States)

    Kim, Yeseul; Lim, Su Jin; Cho, Kun; Weon, Byung Mook

    2016-11-01

    An equilibrium contact angle of a droplet is determined by a horizontal force balance among vapor, liquid, and solid, which is known as Young's law. Conventional wetting law is valid only for axis-symmetric droplets, whereas real droplets are often asymmetric. Here we show that three-dimensional geometry must be considered for a force balance for asymmetric droplets. By visualizing asymmetric droplets placed on a free-standing membrane in air with X-ray microscopy, we are able to identify that force balances in one side and in other side control pinning behaviors during evaporation of droplets. We find that X-ray microscopy is powerful for realizing the three-dimensional force balance, which would be essential in interpretation and manipulation of wetting, spreading, and drying dynamics for asymmetric droplets. This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2016R1D1A1B01007133).

  7. Three dimensional quantum geometry and deformed symmetry

    Science.gov (United States)

    Joung, E.; Mourad, J.; Noui, K.

    2009-05-01

    We study a three dimensional noncommutative space emerging in the context of three dimensional Euclidean quantum gravity. Our starting point is the assumption that the isometry group is deformed to the Drinfeld double D(SU(2)). We generalize to the deformed case the construction of E3 as the quotient of its isometry group ISU(2) by SU(2). We show that the algebra of functions on E3 becomes the noncommutative algebra of SU(2) distributions, C(SU(2))∗, endowed with the convolution product. This construction gives the action of ISU(2) on the algebra and allows the determination of plane waves and coordinate functions. In particular, we show the following: (i) plane waves have bounded momenta; (ii) to a given momentum are associated several SU(2) elements leading to an effective description of ϕ ɛC(SU(2))∗ in terms of several physical scalar fields on E3; (iii) their product leads to a deformed addition rule of momenta consistent with the bound on the spectrum. We generalize to the noncommutative setting the "local" action for a scalar field. Finally, we obtain, using harmonic analysis, another useful description of the algebra as the direct sum of the algebra of matrices. The algebra of matrices inherits the action of ISU(2): rotations leave the order of the matrices invariant, whereas translations change the order in a way we explicitly determine.

  8. Three-dimensional image signals: processing methods

    Science.gov (United States)

    Schiopu, Paul; Manea, Adrian; Craciun, Anca-Ileana; Craciun, Alexandru

    2010-11-01

    Over the years extensive studies have been carried out to apply coherent optics methods in real-time processing, communications and transmission image. This is especially true when a large amount of information needs to be processed, e.g., in high-resolution imaging. The recent progress in data-processing networks and communication systems has considerably increased the capacity of information exchange. We describe the results of literature investigation research of processing methods for the signals of the three-dimensional images. All commercially available 3D technologies today are based on stereoscopic viewing. 3D technology was once the exclusive domain of skilled computer-graphics developers with high-end machines and software. The images capture from the advanced 3D digital camera can be displayed onto screen of the 3D digital viewer with/ without special glasses. For this is needed considerable processing power and memory to create and render the complex mix of colors, textures, and virtual lighting and perspective necessary to make figures appear three-dimensional. Also, using a standard digital camera and a technique called phase-shift interferometry we can capture "digital holograms." These are holograms that can be stored on computer and transmitted over conventional networks. We present some research methods to process "digital holograms" for the Internet transmission and results.

  9. Methods for preparation of three-dimensional bodies

    Energy Technology Data Exchange (ETDEWEB)

    Mulligan, Anthony C [Tucson, AZ; Rigali, Mark J [Carlsbad, NM; Sutaria, Manish P [Malden, MA; Artz, Gregory J [Tucson, AZ; Gafner, Felix H [Tucson, AZ; Vaidyanathan, K Ranji [Tucson, AZ

    2008-06-17

    Processes for mechanically fabricating two and three-dimensional fibrous monolith composites include preparing a fibrous monolith filament from a core composition of a first powder material and a boundary material of a second powder material. The filament includes a first portion of the core composition surrounded by a second portion of the boundary composition. One or more filaments are extruded through a mechanically-controlled deposition nozzle onto a working surface to create a fibrous monolith composite object. The objects may be formed directly from computer models and have complex geometries.

  10. Three-dimensional printing physiology laboratory technology.

    Science.gov (United States)

    Sulkin, Matthew S; Widder, Emily; Shao, Connie; Holzem, Katherine M; Gloschat, Christopher; Gutbrod, Sarah R; Efimov, Igor R

    2013-12-01

    Since its inception in 19th-century Germany, the physiology laboratory has been a complex and expensive research enterprise involving experts in various fields of science and engineering. Physiology research has been critically dependent on cutting-edge technological support of mechanical, electrical, optical, and more recently computer engineers. Evolution of modern experimental equipment is constrained by lack of direct communication between the physiological community and industry producing this equipment. Fortunately, recent advances in open source technologies, including three-dimensional printing, open source hardware and software, present an exciting opportunity to bring the design and development of research instrumentation to the end user, i.e., life scientists. Here we provide an overview on how to develop customized, cost-effective experimental equipment for physiology laboratories.

  11. Three-dimensional context regulation of metastasis.

    Science.gov (United States)

    Erler, Janine T; Weaver, Valerie M

    2009-01-01

    Tumor progression ensues within a three-dimensional microenvironment that consists of cellular and non-cellular components. The extracellular matrix (ECM) and hypoxia are two non-cellular components that potently influence metastasis. ECM remodeling and collagen cross-linking stiffen the tissue stroma to promote transformation, tumor growth, motility and invasion, enhance cancer cell survival, enable metastatic dissemination, and facilitate the establishment of tumor cells at distant sites. Matrix degradation can additionally promote malignant progression and metastasis. Tumor hypoxia is functionally linked to altered stromal-epithelial interactions. Hypoxia additionally induces the expression of pro-migratory, survival and invasion genes, and up-regulates expression of ECM components and modifying enzymes, to enhance tumor progression and metastasis. Synergistic interactions between matrix remodeling and tumor hypoxia influence common mechanisms that maximize tumor progression and cooperate to drive metastasis. Thus, clarifying the molecular pathways by which ECM remodeling and tumor hypoxia intersect to promote tumor progression should identify novel therapeutic targets.

  12. Three-dimensional hologram display system

    Science.gov (United States)

    Mintz, Frederick (Inventor); Chao, Tien-Hsin (Inventor); Bryant, Nevin (Inventor); Tsou, Peter (Inventor)

    2009-01-01

    The present invention relates to a three-dimensional (3D) hologram display system. The 3D hologram display system includes a projector device for projecting an image upon a display medium to form a 3D hologram. The 3D hologram is formed such that a viewer can view the holographic image from multiple angles up to 360 degrees. Multiple display media are described, namely a spinning diffusive screen, a circular diffuser screen, and an aerogel. The spinning diffusive screen utilizes spatial light modulators to control the image such that the 3D image is displayed on the rotating screen in a time-multiplexing manner. The circular diffuser screen includes multiple, simultaneously-operated projectors to project the image onto the circular diffuser screen from a plurality of locations, thereby forming the 3D image. The aerogel can use the projection device described as applicable to either the spinning diffusive screen or the circular diffuser screen.

  13. Entanglement entropy in three dimensional gravity

    CERN Document Server

    Maxfield, Henry

    2014-01-01

    The Ryu-Takayanagi and covariant Hubeny-Rangamani-Takayanagi proposals relate entanglement entropy in CFTs with holographic duals to the areas of minimal or extremal surfaces in the bulk geometry. We show how, in three dimensional pure gravity, the relevant regulated geodesic lengths can be obtained by writing a spacetime as a quotients of AdS3, with the problem reduced to a simple purely algebraic calculation. We explain how this works in both Lorentzian and Euclidean formalisms, before illustrating its use to obtain novel results in a number of examples, including rotating BTZ, the RP2 geon, and several wormhole geometries. This includes spatial and temporal dependence of single-interval entanglement entropy, despite these symmetries being broken only behind an event horizon. We also discuss considerations allowing HRT to be derived from analytic continuation of Euclidean computations in certain contexts, and a related class of complexified extremal surfaces.

  14. Three-Dimensional Pneumatic Molding of Veneers

    Directory of Open Access Journals (Sweden)

    Milan Gaff

    2014-07-01

    Full Text Available The goal of this paper is to introduce a new testing method suitable for the evaluation of the three-dimensional (3-D moldability of veneers and to use this method to test the impact of specific factors on the 3-D pneumatic molding process. The tested factors included veneer moisture content, wood species, shape of test piece, and fixing method on the maximum wood deflection. Veneers were molded using compressed air on equipment designed by our group for the sole purpose of this experiment. The results indicated that the monitored factors had an effect on deflection during the 3-D molding process. The results of this investigation extend the state-of-the-art knowledge regarding this technology and indicate the possibility of utilizing this innovative testing method for 3-D molded veneers.

  15. Three dimensional fabric evolution of sheared sand

    Energy Technology Data Exchange (ETDEWEB)

    Hasan, Alsidqi; Alshibli, Khalid (UWA)

    2012-10-24

    Granular particles undergo translation and rolling when they are sheared. This paper presents a three-dimensional (3D) experimental assessment of fabric evolution of sheared sand at the particle level. F-75 Ottawa sand specimen was tested under an axisymmetric triaxial loading condition. It measured 9.5 mm in diameter and 20 mm in height. The quantitative evaluation was conducted by analyzing 3D high-resolution x-ray synchrotron micro-tomography images of the specimen at eight axial strain levels. The analyses included visualization of particle translation and rotation, and quantification of fabric orientation as shearing continued. Representative individual particles were successfully tracked and visualized to assess the mode of interaction between them. This paper discusses fabric evolution and compares the evolution of particles within and outside the shear band as shearing continues. Changes in particle orientation distributions are presented using fabric histograms and fabric tensor.

  16. Dual solutions for three-dimensional

    Directory of Open Access Journals (Sweden)

    C.S.K. Raju

    2016-03-01

    Full Text Available In this study we investigated the effect of space and temperature dependent heat generation/absorption on three-dimensional magnetohydrodynamic nanofluid flow over a nonlinearly permeable stretching sheet. After using appropriate self-similarity transformation the governing equations are solved numerically using bvp4c Matlab package. The effects of the non-dimensional governing parameters on velocity, temperature and concentration profiles are discussed with the help of graphs. Also, coefficient of skin friction and Nusselt number is analyzed and presented through tables. It is found that present results have an excellent agreement with the existed studies under some special cases. Results indicate that an increase in space and temperature dependent heat source or sink increases the temperature and concentration profiles of the flow. Dual solutions exist only for certain range of power-law index.

  17. Three-Dimensional Reflectance Traction Microscopy.

    Directory of Open Access Journals (Sweden)

    Jihan Kim

    Full Text Available Cells in three-dimensional (3D environments exhibit very different biochemical and biophysical phenotypes compared to the behavior of cells in two-dimensional (2D environments. As an important biomechanical measurement, 2D traction force microscopy can not be directly extended into 3D cases. In order to quantitatively characterize the contraction field, we have developed 3D reflectance traction microscopy which combines confocal reflection imaging and partial volume correlation postprocessing. We have measured the deformation field of collagen gel under controlled mechanical stress. We have also characterized the deformation field generated by invasive breast cancer cells of different morphologies in 3D collagen matrix. In contrast to employ dispersed tracing particles or fluorescently-tagged matrix proteins, our methods provide a label-free, computationally effective strategy to study the cell mechanics in native 3D extracellular matrix.

  18. Steady inviscid three-dimensional flows

    Science.gov (United States)

    Adamczyk, J. J.; Chang, S.-C.

    1985-01-01

    The present analysis combines some of the theoretical concepts suggested by Hawthorne (1955) with a numerical integration procedure suggested by Martin (1978). The resulting algorithm is for inviscid subsonic flows. Thus, it is restricted to high Reynolds number flows. Chang and Adamczyk (1983) have provided a detailed derivation of the present algorithm along with a discussion of its stability bounds. The present paper represents a summary of this work. The integration of the continuity equation is considered along with an evaluation of the entropy, total temperature, and vorticity field. Attention is given to the shear-flow algorithm construction, and an application to a shear flow in a turning channel. A description of numerical results is also provided. The discussed algorithm represents a new procedure for solving inviscid subsonic three-dimensional rotational flows.

  19. Scaffolding for Three-Dimensional Embryonic Vasculogenesis

    Science.gov (United States)

    Kraehenbuehl, Thomas P.; Aday, Sezin; Ferreira, Lino S.

    Biomaterial scaffolds have great potential to support efficient vascular differentiation of embryonic stem cells. Vascular cell fate-specific biochemical and biophysical cues have been identified and incorporated into three-dimensional (3D) biomaterials to efficiently direct embryonic vasculogenesis. The resulting vascular-like tissue can be used for regenerative medicine applications, further elucidation of biophysical and biochemical cues governing vasculogenesis, and drug discovery. In this chapter, we give an overview on the following: (1) developmental cues for directed differentiation of human embryonic stem cells (hESCs) into vascular cells, (2) 3D vascular differentiation in embryoid bodies (EBs), (3) preparation of 3D scaffolds for the vascular differentiation of hESCs, and (4) the most significant studies combining scaffolding and hESCs for development of vascular-like tissue.

  20. Three-dimensional tori and Arnold tongues

    Energy Technology Data Exchange (ETDEWEB)

    Sekikawa, Munehisa, E-mail: sekikawa@cc.utsunomiya-u.ac.jp [Department of Mechanical and Intelligent Engineering, Utsunomiya University, Utsunomiya-shi 321-8585 (Japan); Inaba, Naohiko [Organization for the Strategic Coordination of Research and Intellectual Property, Meiji University, Kawasaki-shi 214-8571 (Japan); Kamiyama, Kyohei [Department of Electronics and Bioinformatics, Meiji University, Kawasaki-shi 214-8571 (Japan); Aihara, Kazuyuki [Institute of Industrial Science, the University of Tokyo, Meguro-ku 153-8505 (Japan)

    2014-03-15

    This study analyzes an Arnold resonance web, which includes complicated quasi-periodic bifurcations, by conducting a Lyapunov analysis for a coupled delayed logistic map. The map can exhibit a two-dimensional invariant torus (IT), which corresponds to a three-dimensional torus in vector fields. Numerous one-dimensional invariant closed curves (ICCs), which correspond to two-dimensional tori in vector fields, exist in a very complicated but reasonable manner inside an IT-generating region. Periodic solutions emerge at the intersections of two different thin ICC-generating regions, which we call ICC-Arnold tongues, because all three independent-frequency components of the IT become rational at the intersections. Additionally, we observe a significant bifurcation structure where conventional Arnold tongues transit to ICC-Arnold tongues through a Neimark-Sacker bifurcation in the neighborhood of a quasi-periodic Hopf bifurcation (or a quasi-periodic Neimark-Sacker bifurcation) boundary.

  1. Entanglement entropy in three dimensional gravity

    Energy Technology Data Exchange (ETDEWEB)

    Maxfield, Henry [Centre for Particle Theory & Department of Mathematical Sciences, Durham University,South Road, Durham DH1 3LE (United Kingdom)

    2015-04-07

    The Ryu-Takayanagi (RT) and covariant Hubeny-Rangamani-Takayanagi (HRT) proposals relate entanglement entropy in CFTs with holographic duals to the areas of minimal or extremal surfaces in the bulk geometry. We show how, in three dimensional pure gravity, the relevant regulated geodesic lengths can be obtained by writing a spacetime as a quotient of AdS{sub 3}, with the problem reduced to a simple purely algebraic calculation. We explain how this works in both Lorentzian and Euclidean formalisms, before illustrating its use to obtain novel results in a number of examples, including rotating BTZ, the ℝℙ{sup 2} geon, and several wormhole geometries. This includes spatial and temporal dependence of single-interval entanglement entropy, despite these symmetries being broken only behind an event horizon. We also discuss considerations allowing HRT to be derived from analytic continuation of Euclidean computations in certain contexts, and a related class of complexified extremal surfaces.

  2. AAOGlimpse: Three-dimensional Data Viewer

    Science.gov (United States)

    Shortridge, Keith

    2011-10-01

    AAOGlimpse is an experimental display program that uses OpenGL to display FITS data (and even JPEG images) as 3D surfaces that can be rotated and viewed from different angles, all in real-time. It is WCS-compliant and designed to handle three-dimensional data. Each plane in a data cube is surfaced in the same way, and the program allows the user to travel through a cube by 'peeling off' successive planes, or to look into a cube by suppressing the display of data below a given cutoff value. It can blink images and can superimpose images and contour maps from different sources using their world coordinate data. A limited socket interface allows communication with other programs.

  3. Three dimensional polymer waveguide using hybrid lithography.

    Science.gov (United States)

    Wang, Huanran; Liu, Yu; Jiang, Minghui; Chen, Changming; Wang, Xibin; Wang, Fei; Zhang, Daming; Yi, Yunji

    2015-10-01

    A three dimensional polymer waveguide with taper structure was demonstrated and fabricated by a reliable and effective hybrid lithography. The hybrid lithography consists of lithography to fabricate a polymer waveguide and gray scale lithography to fabricate a polymer taper structure. Laser ablation and shadow aluminum evaporation were designed for gray scale lithography. The length of the gray scale region ranging from 20 to 400 μm could be controlled by the laser power, the ablation speed, and the aluminum thickness. The slope angle was determined by the length of the gray scale region and the thickness of the photoresist. The waveguide taper structure could be transferred to the lower layer by the etching method. The taper structure can be used for integration of the waveguide with different dimensions.

  4. Three-dimensional printing of biological matters

    Directory of Open Access Journals (Sweden)

    Ahmed Munaz

    2016-03-01

    Full Text Available Three-dimensional (3D printing of human tissues and organ has been an exciting research topic in the past three decades. However, existing technological and biological challenges still require a significant amount of research. The present review highlights these challenges and discusses their potential solutions such as mapping and converting a human organ onto a 3D virtual design, synchronizing the virtual design with the printing hardware. Moreover, the paper discusses in details recent advances in formulating bio-inks and challenges in tissue construction with or without scaffold. Next, the paper reviews fusion processes effecting vascular cells and tissues. Finally, the paper deliberates the feasibility of organ printing with state-of-the-art technologies.

  5. Localized shear generates three-dimensional transport

    Science.gov (United States)

    Smith, Lachlan D.; Rudman, Murray; Lester, Daniel R.; Metcalfe, Guy

    2017-04-01

    Understanding the mechanisms that control three-dimensional (3D) fluid transport is central to many processes, including mixing, chemical reaction, and biological activity. Here a novel mechanism for 3D transport is uncovered where fluid particles are kicked between streamlines near a localized shear, which occurs in many flows and materials. This results in 3D transport similar to Resonance Induced Dispersion (RID); however, this new mechanism is more rapid and mutually incompatible with RID. We explore its governing impact with both an abstract 2-action flow and a model fluid flow. We show that transitions from one-dimensional (1D) to two-dimensional (2D) and 2D to 3D transport occur based on the relative magnitudes of streamline jumps in two transverse directions.

  6. GaN three dimensional nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Dmitriev, V.; Irvin, K. [Cree Research, Inc., Durham, NC (United States); Zubrilov, A.; Tsvetkov, D.; Nikolaev, V. [Cree Research EED, St. Petersburg (Russian Federation); Jakobson, M.; Nelson, D.; Sitnikova, A. [A.F. Ioffe Inst., St. Petersburg (Russian Federation)

    1996-11-01

    The authors report on the growth and characterization of three dimensional nanoscale structures of GaN. GaN dots were grown by metal organic chemical vapor deposition (MOCVD) on 6H-SiC substrates. The actual size of the dots measured by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) ranged from {approximately}20 nm to more than 2 {micro}m. The average dot density ranged from 10{sup 7} to 10{sup 9} cm{sup {minus}2}. The single crystal structure of the dots was verified by reflectance high energy electron diffraction (HEED) and TEM. Cathodoluminescence (CL) and photoluminescence (PL) of the dots were studied at various temperatures and excitation levels. The PL and CL edge peak for the GaN dots exhibited a blue shift as compared with edge peak position for continuous GaN layers grown on SiC.

  7. Exact solutions in three-dimensional gravity

    CERN Document Server

    Garcia-Diaz, Alberto A

    2017-01-01

    A self-contained text, systematically presenting the determination and classification of exact solutions in three-dimensional Einstein gravity. This book explores the theoretical framework and general physical and geometrical characteristics of each class of solutions, and includes information on the researchers responsible for their discovery. Beginning with the physical character of the solutions, these are identified and ordered on the basis of their geometrical invariant properties, symmetries, and algebraic classifications, or from the standpoint of their physical nature, for example electrodynamic fields, fluid, scalar field, or dilaton. Consequently, this text serves as a thorough catalogue on 2+1 exact solutions to the Einstein equations coupled to matter and fields, and on vacuum solutions of topologically massive gravity with a cosmological constant. The solutions are also examined from different perspectives, enabling a conceptual bridge between exact solutions of three- and four-dimensional gravit...

  8. Lattice Three-Dimensional Skyrmions Revisited

    CERN Document Server

    Charalampidis, E G; Kevrekidis, P G

    2014-01-01

    In the continuum a skyrmion is a topological nontrivial map between Riemannian manifolds, and a stationary point of a particular energy functional. This paper describes lattice analogues of the aforementioned skyrmions, namely a natural way of using the topological properties of the three-dimensional continuum Skyrme model to achieve topological stability on the lattice. In particular, using fixed point iterations, numerically exact lattice skyrmions are constructed; and their stability under small perturbations is verified by means of linear stability analysis. While stable branches of such solutions are identified, it is also shown that they possess a particularly delicate bifurcation structure, especially so in the vicinity of the continuum limit. The corresponding bifurcation diagram is elucidated and a prescription for selecting the branch asymptoting to the well-known continuum limit is given. Finally, the robustness of the solutions by virtue of direct numerical simulations is corroborated.

  9. Simulation for transthoracic echocardiography of aortic valve

    Science.gov (United States)

    Nanda, Navin C.; Kapur, K. K.; Kapoor, Poonam Malhotra

    2016-01-01

    Simulation allows interactive transthoracic echocardiography (TTE) learning using a virtual three-dimensional model of the heart and may aid in the acquisition of the cognitive and technical skills needed to perform TTE. The ability to link probe manipulation, cardiac anatomy, and echocardiographic images using a simulator has been shown to be an effective model for training anesthesiology residents in transesophageal echocardiography. A proposed alternative to real-time reality patient-based learning is simulation-based training that allows anesthesiologists to learn complex concepts and procedures, especially for specific structures such as aortic valve. PMID:27397455

  10. Three-dimensional (3D) analysis of the temporomandibular joint

    DEFF Research Database (Denmark)

    Kitai, N.; Kreiborg, S.; Murakami, S.

    Symposium Orthodontics 2001: Where are We Now? Where are We Going?, three-dimensional analysis, temporomandibular joint......Symposium Orthodontics 2001: Where are We Now? Where are We Going?, three-dimensional analysis, temporomandibular joint...

  11. Springback prediction of three-dimensional variable curvature tube bending

    National Research Council Canada - National Science Library

    Zhang, Shen; Wu, Jianjun

    2016-01-01

    .... The springback prediction of three-dimensional variable curvature bent tube is projected on each discrete osculating and rectifying plane, and then the three-dimensional problem can be transformed into two dimensions...

  12. Three-dimensional echocardiographic imaging of biventricular false tendons mimicking hypertrophic cardiomyopathy.

    Science.gov (United States)

    Kucuk, Ugur; Demirkol, Sait; Celik, Turgay; Balta, Sevket; Yokusoglu, Mehmet

    2012-08-01

    Hypertrophic cardiomyopathy (HCM) is characterized by hypertrophy of the left ventricle, with variable clinical manifestations and morphologic and hemodynamic abnormalities. False tendons (FTs) are discrete, fibromuscular structures of varying length and thickness that tranverse either left and right ventricular cavities. Left and right ventricular FTs were giving a false impression of HCM. Misdiagnosis of HCM can lead to undue anxiety, unnecessary medication, and further evaluation. Three-dimensional (3D) transthoracic echocardiography is additive to conventional two-dimensional imaging in these patients in terms of 3D perspective and anatomically correct examination. We present a 32-year-old male who was misdiagnosed as asymetrical septal hypertrophy.

  13. Live/Real Time Three-Dimensional Trans Esophageal Echocardiographic Findings in Amplatzer ASD Closure Devices in Adults

    Directory of Open Access Journals (Sweden)

    Fatemeh Nabavizadeh

    2012-09-01

    Full Text Available Six female patients aged from 19 to 73 years, with ostium secundum atrial septal defect underwent closure procedure with Amplatzer septal occluder device. Three-dimensional Echocardiography (3D-TEE was done during the procedure or one day after the procedure. 3D-TEE provides incremental value over Two- dimensional trans-esophageal echocardiography in measuring Amplatzer septal occluder disc sizes and correlates well with manufacture device size. 3D-TEE will surely prove to increase the technical efficiency and it will become an important tool for the interventionists for periprocedural evaluation of device closures.

  14. Application of two-and three-dimensional ultrasound in diagnosis of fetal cleft lip with or without cleft palate%二维及三维超声在胎儿唇腭裂产前诊断中的应用

    Institute of Scientific and Technical Information of China (English)

    席梅; 刘卫星; 曾莉; 温岳君; 张雪梅; 毕营营; 郭慧越

    2013-01-01

    other organ malformations( 1 cases of wide distance between the eyes and strephexopodia;1 cases of cardiac malformation;1 cases of hand deformities ).Conclusion Three-dimensional ultrasound reconstruction based on two-dimensional ultrasound,it enriches the two-dimensional ultrasound imaging information ,application of two and three-dimensional ultrasound in the diagnosis of fetal cleft lip with or without cleft palate can improve the diagnostic accuracy and reduce missed diagnosis or misdiagnosis .%  目的总结胎儿唇裂及唇腭裂二维超声及三维超声声像图特征。方法应用二维超声及三维超声多种成像模式重建法对10268例胎儿行产前唇腭部超声筛查,并与引产或产后检查结果进行对照分析,总结胎儿唇腭裂超声声像图特征。结果10268例胎儿经引产(9例)或胎儿自然分娩后(1例单胎,1例双胎)检查证实产前二维超声正确诊断唇腭裂畸形9例,三维超声正确诊断唇腭裂畸形10例。其中二维超声漏诊1例唇腭裂,三维超声诊断为Ⅲ度唇腭裂;二维及三维超声均漏诊1例Ⅰ度唇裂:二维超声无异常表现,三维超声表面成像模式显示胎儿唇红处可疑回声缺失,误诊为胎儿人中,胎儿自然分娩后证实新生儿为Ⅰ度唇裂。11例唇腭裂胎儿产前超声声像图表现:(1)单纯唇裂3例,超声声像图示一侧或双侧上唇部连续性中断,回声缺失;(2)唇腭裂合并牙槽突裂7例,腭部连续性中断,回声缺失。(3)三维超声表面成像及断层成像(TUI)模式可直观、立体显示胎儿唇裂类型,诊断唇裂3例,唇腭裂7例;骨骼成像及TUI模式显示牙槽突至鼻切迹处的上颌体不连续回声图像,旋转X轴连贯显示硬腭的连续性中断。(4)唇腭裂合并其他畸形3例,其中唇腭裂合并足外翻和眼距宽1例、心脏畸形1例,手畸形1例。结论建立在二维超声基础上的三维超

  15. Primary and Secondary Three Dimensional Microbatteries

    Science.gov (United States)

    Cirigliano, Nicolas

    Today's MEMS devices are limited more so by the batteries that supply their power than the fabrication methods used to build them. Thick battery electrodes are capable of providing adequate energy, but long and tortuous diffusion pathways lead to low power capabilities. On the other hand, thin film batteries can operate at significant current densities but require large surface areas to supply practical energy. This dilemma can be solved by either developing new high capacity materials or by engineering new battery designs that decouple power and energy. Three dimensional batteries redesign traditional configurations to create nonplanar interfaces between battery components. This can be done by introducing hierarchical structures into the electrode shape. Designs such as these provide a maximum surface area over which chemical reactions can occur. Furthermore, by maintaining small feature sizes, ion diffusion and electronic transport distances can remain minimal. Manipulating these properties ensures fast kinetics that are required for high power situations. Energy density is maximized by layering material in the vertical direction, thus ensuring a minimal footprint area. Three dimensional carbon electrodes are fabricated using basic MEMS techniques. A silicon mold is anisotropically etched to produce channels of a predetermined diameter. The channels are then filled using an infiltration technique with electrode slurry. Once dried, the mold is attached to a current collector and etched using a XeF2 process. Electrodes of varying feature sizes have been fabricated using this method with aspect ratios ranging from 3.5:1 to 7:1. 3D carbon electrodes are shown to obtain capacities over 8 mAh/cm2 at 0.1 mA/cm2, or nearly 700% higher than planar carbon electrodes. When assembled with a planar cathode, the battery cell produced an average discharge capacity of 40 J/cm 2 at a current density of 0.2 mA/cm2. This places the energy density values slightly less than thick

  16. Understanding three-dimensional damage envelopes

    Science.gov (United States)

    Browning, John; Harland, Sophie; Meredith, Philip; Healy, David; Mitchell, Tom

    2017-04-01

    Microcrack damage leading to failure in rocks evolves in response to differential loading. This loading is often visualized in a two-dimensional stress space through the use of Mohr-Coulomb diagrams. The vast majority of experimental studies investigate damage evolution and rock failure using conventional triaxial stress states (σ1 > σ2 = σ3) in which the results can be easily represented in a Mohr-Coulomb plot. However, in nature the stress state is in general truly triaxial (σ1 > σ2 > σ3) and as such comprises a 3D stress state potentially leading to more complexity. By monitoring acoustic wave velocities and acoustic emissions we have shown that damage is generated in multiple orientations depending on the loading directions and hence principal stress directions. Furthermore, crack growth is shown to be a function of differential stress regardless of the mean stress. As such, new cracks can form due to a decrease in the minimum principal stress, which reduces mean stress but increases the differential stress. Although the size of individual cracks is not affected by the intermediate principal stress it has been shown that the σ2 plays a key role in suppressing the total amount of crack growth and concentrates this damage in a single plane. Hence, the differential stress at which rocks fail (i.e. the rock strength) will be significantly increased under true triaxial stress conditions than under the much more commonly applied condition of conventional triaxial stress. Through a series of cyclic loading tests we investigated the Kaiser effect, we show that while individual stress states are important, the stress path by which this stress state is reached is equally important. Whether or not a stress state has been 'visited' before is also vitally important in determining and understanding damage envelopes. Finally, we show that damage evolution can be anisotropic and must be considered as a three-dimensional problem. It is unclear how damage envelopes

  17. [Relationships between right atrial and left ventricular size and function in health subjects. Results from the three-dimensional speckle-tracking echocardiographic MAGYAR-Healthy Study].

    Science.gov (United States)

    Piros, Györgyike Ágnes; Domsik, Péter; Kalapos, Anita; Lengyel, Csaba; Orosz, Andrea; Forster, Tamás; Nemes, Attila

    2015-06-14

    The heart cycle includes systole and diastole when the heart chambers are characterized by a complex motion. The present study was designed to test whether relationships exist between three-dimensional speckle-tracking echocardiography-derived right atrial and routine two-dimensional echocardiography-derived left ventricular volumetric and functional parameters is healthy subjects. The present study comprised 20 healthy volunteers. Complete two-dimensional echocardiography and three-dimensional speckle-tracking echocardiography were perfomed in all cases. Left ventricular ejection fraction showed correlations with systolic and diastolic right atrial volumes and area strain characterzing atrial contraction in diastole. Right atrial volumes respective of cardiac cycle correlated only with left ventricular end-systolic diameter and volume, while similar relationships could not be confirmed with end-diastolic parameters. Relationships could be demonstrated between three-dimensional speckle-tracking echocardiography-derived right atrial and two-dimensional echocardiography-derived left ventricular volumetric and functional parameters in healthy subjects.

  18. Three Dimensional CAPP Technology of Projectile Based on MBD

    Directory of Open Access Journals (Sweden)

    Hongzhi Zhao

    2013-07-01

    Full Text Available This study aims at the research goal of three-dimensional digital process design of projectile, which adopts three-dimensional computer-aided process design technology based on MBD and uses MBD to conduct parametric modeling of projectile that can reduce the input of projectile’s process information and data conversion and produce reasonable, feasible and three-dimensional projectile manufacturing process to realize paperless three-dimensional process design of projectile. The application of three-dimensional computer-assisted process design technology of projectile based on model definition can shorten the design cycle of projectile, thus improving rapid manufacturing capacity of product and reducing cost.

  19. THEORETICAL STUDY OF THREE-DIMENSIONAL NUMERICAL MANIFOLD METHOD

    Institute of Scientific and Technical Information of China (English)

    LUO Shao-ming; ZHANG Xiang-wei; L(U) Wen-ge; JIANG Dong-ru

    2005-01-01

    The three-dimensional numerical manifold method(NMM) is studied on the basis of two-dimensional numerical manifold method. The three-dimensional cover displacement function is studied. The mechanical analysis and Hammer integral method of three-dimensional numerical manifold method are put forward. The stiffness matrix of three-dimensional manifold element is derived and the dissection rules are given. The theoretical system and the numerical realizing method of three-dimensional numerical manifold method are systematically studied. As an example, the cantilever with load on the end is calculated, and the results show that the precision and efficiency are agreeable.

  20. Dynamic 3D echocardiography in virtual reality

    Directory of Open Access Journals (Sweden)

    Simoons Maarten L

    2005-12-01

    Full Text Available Abstract Background This pilot study was performed to evaluate whether virtual reality is applicable for three-dimensional echocardiography and if three-dimensional echocardiographic 'holograms' have the potential to become a clinically useful tool. Methods Three-dimensional echocardiographic data sets from 2 normal subjects and from 4 patients with a mitral valve pathological condition were included in the study. The three-dimensional data sets were acquired with the Philips Sonos 7500 echo-system and transferred to the BARCO (Barco N.V., Kortrijk, Belgium I-space. Ten independent observers assessed the 6 three-dimensional data sets with and without mitral valve pathology. After 10 minutes' instruction in the I-Space, all of the observers could use the virtual pointer that is necessary to create cut planes in the hologram. Results The 10 independent observers correctly assessed the normal and pathological mitral valve in the holograms (analysis time approximately 10 minutes. Conclusion this report shows that dynamic holographic imaging of three-dimensional echocardiographic data is feasible. However, the applicability and use-fullness of this technology in clinical practice is still limited.

  1. Three dimensional characterization and archiving system

    Energy Technology Data Exchange (ETDEWEB)

    Sebastian, R.L.; Clark, R.; Gallman, P. [Coleman Research Corp., Springfield, VA (United States)] [and others

    1995-10-01

    The Three Dimensional Characterization and Archiving System (3D-ICAS) is being developed as a remote system to perform rapid in situ analysis of hazardous organics and radionuclide contamination on structural materials. Coleman Research and its subcontractors, Thermedics Detection, Inc. (TD) and the University of Idaho (UI) are in the second phase of a three phase program to develop 3D-ICAS to support Decontamination and Decommissioning (D&D) operations. Accurate physical characterization of surfaces and the radioactive and organic is a critical D&D task. Surface characterization includes identification of potentially dangerous inorganic materials, such as asbestos and transite. The 3D-ICAS system robotically conveys a multisensor probe near the surface to be inspected. The sensor position and orientation are monitored and controlled by Coherent laser radar (CLR) tracking. The ICAS fills the need for high speed automated organic analysis by means of gas chromatography-mass spectrometry sensors, and also by radionuclide sensors which combines alpha, beta, and gamma counting.

  2. Clinical significance of three-dimensional sonohysterography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Hye; Lee, Mi Hwa; Lee, Chan; Kim, Jong Wook; Shin, Myung Choel [Pochon Cha University College of Medicine, Pochon (Korea, Republic of)

    1999-12-15

    To evaluate the usefulness of three dimensional sonohysterography (3D SHG) in the evaluation of uterine endometrial and submucosal lesions in comparison with conventional two-dimensional sonohysterography (2D SHG). Our series consisted of 26 patients (mean aged 41 years) who complained of uterine bleeding, menorrhagia, or dysmenorrhea. 2D SHG was performed, and then 3D SHG was done after the volume mode was switched on. Simultaneous display of three perpendicular two-dimensional planes and surface rendering of findings on particular section were obtained. We analyzed whether the endometrium was thickened or not, and the location, size, shape, echogenicity, posterior shadowing, and echogenic rim of the focal lesion. The results were compared with the pathologic findings or MRI. There were submucosal myomas (n=12), intramural myomas (n=2), endometrial polyps (n=7), placental polyp (n=1), and normal endometrial cavities (n=4) on SHG. Nineteen cases were confirmed by pathologic findings or MRI. The results were correlated in 89% (17/19) of the cases. We misdiagnosed 2 cases: focal endometrial hyperplasia and choriocarcinoma were misdiagnosed as endometrial polyp and placental polyp, respectively. Imaging diagnoses were same in the techniques. Comparing with 2D SHG, 3D SHG provided a subjective display of pathologic findings and an additional information about spatial relationship between focal lesion and surroundings.

  3. Globographic visualisation of three dimensional joint angles.

    Science.gov (United States)

    Baker, Richard

    2011-07-07

    Three different methods for describing three dimensional joint angles are commonly used in biomechanics. The joint coordinate system and Cardan/Euler angles are conceptually quite different but are known to represent the same underlying mathematics. More recently the globographic method has been suggested as an alternative and this has proved particularly attractive for the shoulder joint. All three methods can be implemented in a number of ways leading to a choice of angle definitions. Very recently Rab has demonstrated that the globographic method is equivalent to one implementation of the joint coordinate system. This paper presents a rigorous analysis of the three different methods and proves their mathematical equivalence. The well known sequence dependence of Cardan/Euler is presented as equivalent to configuration dependence of the joint coordinate system and orientation dependence of globographic angles. The precise definition of different angle sets can be easily visualised using the globographic method using analogues of longitude, latitude and surface bearings with which most users will already be familiar. The method implicitly requires one axis of the moving segment to be identified as its principal axis and this can be extremely useful in helping define the most appropriate angle set to describe the orientation of any particular joint. Using this technique different angle sets are considered to be most appropriate for different joints and examples of this for the hip, knee, ankle, pelvis and axial skeleton are outlined.

  4. Three dimensional characterization and archiving system

    Energy Technology Data Exchange (ETDEWEB)

    Sebastian, R.L.; Clark, R.; Gallman, P. [and others

    1995-12-01

    The Three Dimensional Characterization and Archiving System (3D-ICAS) is being developed as a remote system to perform rapid in situ analysis of hazardous organics and radionuclide contamination on structural materials. Coleman Research and its subcontractors, Thermedics Detection, Inc. (TD) and the University of Idaho (UI) are in the second phase of a three phase program to develop 3D-ICAS to support Decontamination and Decommissioning (D&D) operations. Accurate physical characterization of surfaces and the radioactive and organic is a critical D&D task. Surface characterization includes identification of potentially dangerous inorganic materials, such as asbestos and transite. Real-time remotely operable characterization instrumentation will significantly advance the analysis capabilities beyond those currently employed. Chemical analysis is a primary area where the characterization process will be improved. Chemical analysis plays a vital role throughout the process of decontamination. Before clean-up operations can begin the site must be characterized with respect to the type and concentration of contaminants, and detailed site mapping must clarify areas of both high and low risk. During remediation activities chemical analysis provides a means to measure progress and to adjust clean-up strategy. Once the clean-up process has been completed the results of chemical analysis will verify that the site is in compliance with federal and local regulations.

  5. Three Dimensional Hydrodynamic Model With Multiquadtree Meshes

    Directory of Open Access Journals (Sweden)

    G. P. Vanegas

    2008-01-01

    Full Text Available This study presents a three dimensional model for the transport of conservative contaminants, which can be used for bodies of water which are affected by winds and/or tides. The model solves the equation of mass transport, based on results obtained using a hydrodynamic model for shallow waters that works in a finite volume scheme and a type of hierarchical grid, called multi-quadtree, which is adaptable to the bathymetry. To solve the vertical coordinates, the coordinate z is transformed into a sigma (σ coordinate, thus allowing the same number of layers in the vertical, regardless of depth. This hydrodynamic model is validated using two cases: a long wave propagated in a channel of variable width and bottom and wind action in a rectangular basin. Finally, the results obtained are presented for a hypothetical single port outfall in the bay of Campeche, México. The model developed here is both quick and easy to use and is efficient when compared with models presented by other authors since it uses adaptable grids which allow detailed solutions to be obtained for areas of interest such as coastlines and the area around an outfall.

  6. Three-dimensionally Perforated Calcium Phosphate Ceramics

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Porous calcium phosphate ceramics were produced by compression molding using a special mold followed by sintering. The porous calcium phosphate ceramics have three-dimensional and penetrated open pores380-400μm in diameter spaced at intervals of 200μm. The layers of the linear penetration pores alternately lay perpendicular to pore direction. The porosity was 59%-65% . The Ca/P molar ratios of the porous calcium phosphate ceramics range from 1.5 to 1.85. A binder containing methyl cellulose was most effective for preparing the powder compact among vinyl acetate, polyvinyl alcohol, starch, stearic acid, methyl cellulose and their mixtures. Stainless steel, polystyrene, nylon and bamboo were used as the long columnar male dies for the penetrated open pores. When polystyrene, nylon and bamboo were used as the long columnar male dies, the dies were burned out during the sintering process. Using stainless steel as the male dies with the removal of the dies before heat treatment resulted in a higher level of densification of the calcium phosphate ceramic.

  7. Three-dimensional survey of paint layer

    Science.gov (United States)

    Pampaloni, Enrico; Bellucci, Roberto; Carcagni, Pierluigi; Casaccia, Antonella; Fontana, Raffaella; Gambino, Maria Chiara; Piccolo, Roberta; Pingi, Paolo; Pezzati, Luca

    2007-07-01

    The quantitative morphological analysis of a painting surface allows to evidence form defects and to study, thus, their influence on the stability of the paint and preparatory layers, as well as of the support. Therefore a three-dimensional survey can be very useful in planning the restoration intervention of a painting. In this work we present the results of the surface analysis carried out on the painting "Ultima Cena" by Giorgio Vasari. This panel painting is severely affected by paint film wrinkling produced as a consequence of the flood that occurred in Florence in 1966. Our analysis, accomplished to quantify the lengthening of the paint layer with respect to the one of the support in order to plan the restoration intervention, was performed on 25 profiles separated each by 10 cm in order to cover the whole painting surface. A data analysis, based on morphological filtering named "Rolling Ball" transformation, was used to evaluate the length difference between the paint layer and the panel support along each profile.

  8. Why Observable Space Is Solely Three Dimensional

    CERN Document Server

    Rabinowitz, Mario

    2015-01-01

    Quantum (and classical) binding energy considerations in n-dimensional space indicate that atoms (and planets) can only exist in three-dimensional space. This is why observable space is solely 3-dimensional. Both a novel Virial theorem analysis, and detailed classical and quantum energy calculations for 3-space circular and elliptical orbits indicate that they have no orbital binding energy in greater than 3-space. The same energy equation also excludes the possibility of atom-like bodies in strictly 1 and 2-dimensions. A prediction is made that in the search for deviations from r^-2 of the gravitational force at sub-millimeter distances such a deviation must occur at < ~ 10^-10 m (or < ~10^-12 m considering muoniom), since atoms would disintegrate if the curled up dimensions of string theory were larger than this. Callender asserts that the often-repeated claim in previous work that stable orbits are possible in only three dimensions is not even remotely established. The binding energy analysis herein ...

  9. Three dimensional modeling of CR propagation

    CERN Document Server

    Gaggero, Daniele; Di Bernardo, Giuseppe; Evoli, Carmelo; Grasso, Dario

    2013-01-01

    We present here a major upgrade of DRAGON, a numerical package that computes the propagation of a wide set of CR species from both astrophysical and exotic origin in the Galaxy in a wide energy range from tens of MeV to tens of TeV. DRAGON takes into account all relevant processes in particular diffusion, convection, reacceleration, fragmentation and energy losses. For the first time, we present a full 3D version of DRAGON with anisotropic position-dependent diffusion. In this version, the propagation is calculated within a 3D cartesian grid and the user is able to implement realistic and structured three dimensional source, gas and regular magnetic field distributions. Moreover, it is possible to specify an arbitrary function of position and rigidity for the diffusion coefficients in the parallel and perpendicular direction to the regular magnetic field of the Galaxy. The code opens many new possibilities in the study of CR physics. In particular, we can study for the first time the impact of the spiral arm ...

  10. Three-Dimensional Printed Graphene Foams.

    Science.gov (United States)

    Sha, Junwei; Li, Yilun; Villegas Salvatierra, Rodrigo; Wang, Tuo; Dong, Pei; Ji, Yongsung; Lee, Seoung-Ki; Zhang, Chenhao; Zhang, Jibo; Smith, Robert H; Ajayan, Pulickel M; Lou, Jun; Zhao, Naiqin; Tour, James M

    2017-07-25

    An automated metal powder three-dimensional (3D) printing method for in situ synthesis of free-standing 3D graphene foams (GFs) was successfully modeled by manually placing a mixture of Ni and sucrose onto a platform and then using a commercial CO2 laser to convert the Ni/sucrose mixture into 3D GFs. The sucrose acted as the solid carbon source for graphene, and the sintered Ni metal acted as the catalyst and template for graphene growth. This simple and efficient method combines powder metallurgy templating with 3D printing techniques and enables direct in situ 3D printing of GFs with no high-temperature furnace or lengthy growth process required. The 3D printed GFs show high-porosity (∼99.3%), low-density (∼0.015g cm(-3)), high-quality, and multilayered graphene features. The GFs have an electrical conductivity of ∼8.7 S cm(-1), a remarkable storage modulus of ∼11 kPa, and a high damping capacity of ∼0.06. These excellent physical properties of 3D printed GFs indicate potential applications in fields requiring rapid design and manufacturing of 3D carbon materials, for example, energy storage devices, damping materials, and sound absorption.

  11. Chaotic Mixing in Three Dimensional Porous Media

    CERN Document Server

    Lester, Daniel R; Borgne, Tanguy Le

    2016-01-01

    Under steady flow conditions, the topological complexity inherent to all random 3D porous media imparts complicated flow and transport dynamics. It has been established that this complexity generates persistent chaotic advection via a three-dimensional (3D) fluid mechanical analogue of the baker's map which rapidly accelerates scalar mixing in the presence of molecular di?usion. Hence pore-scale fluid mixing is governed by the interplay between chaotic advection, molecular di?usion and the broad (power-law) distribution of fluid particle travel times which arise from the non-slip condition at pore walls. To understand and quantify mixing in 3D porous media, we consider these processes in a model 3D open porous network and develop a novel stretching continuous time random walk (CTRW) which provides analytic estimates of pore-scale mixing which compare well with direct numerical simulations. We ?nd that chaotic advection inherent to 3D porous media imparts scalar mixing which scales exponentially with longitudi...

  12. Three dimensional characterization and archiving system

    Energy Technology Data Exchange (ETDEWEB)

    Sebastian, R.L.; Clark, R.; Gallman, P. [and others

    1996-04-01

    The Three Dimensional Characterization and Archiving System (3D-ICAS) is being developed as a remote system to perform rapid in situ analysis of hazardous organics and radionuclide contamination on structural materials. Coleman Research and its subcontractors, Thermedics Detection, Inc. (TD) and the University of Idaho (UI) are in the second phase of a three phase program to develop 3D-ICAS to support Decontamination and Decommissioning (D and D) operations. Accurate physical characterization of surfaces and the radioactive and organic is a critical D and D task. Surface characterization includes identification of potentially dangerous inorganic materials, such as asbestos and transite. Real-time remotely operable characterization instrumentation will significantly advance the analysis capabilities beyond those currently employed. Chemical analysis is a primary area where the characterization process will be improved. The 3D-ICAS system robotically conveys a multisensor probe near the surfaces to be inspected. The sensor position and orientation are monitored and controlled using coherent laser radar (CLR) tracking. The CLR also provides 3D facility maps which establish a 3D world view within which the robotic sensor system can operate.

  13. Three-dimensional Printing in the Intestine.

    Science.gov (United States)

    Wengerter, Brian C; Emre, Gulus; Park, Jea Young; Geibel, John

    2016-08-01

    Intestinal transplantation remains a life-saving option for patients with severe intestinal failure. With the advent of advanced tissue engineering techniques, great strides have been made toward manufacturing replacement tissues and organs, including the intestine, which aim to avoid transplant-related complications. The current paradigm is to seed a biocompatible support material (scaffold) with a desired cell population to generate viable replacement tissue. Although this technique has now been extended by the three-dimensional (3D) printing of geometrically complex scaffolds, the overall approach is hindered by relatively slow turnover and negative effects of residual scaffold material, which affects final clinical outcome. Methods recently developed for scaffold-free 3D bioprinting may overcome such obstacles and should allow for rapid manufacture and deployment of "bioprinted organs." Much work remains before 3D bioprinted tissues can enter clinical use. In this brief review we examine the present state and future perspectives of this nascent technology before full clinical implementation.

  14. 3N Scattering in a Three-Dimensional Operator Formulation

    CERN Document Server

    Glöckle, W; Elster, Ch; Golak, J; Skibinski, R; Witala, H

    2009-01-01

    A recently developed formulation for a direct treatment of the equations for two- and three-nucleon bound states as set of coupled equations of scalar functions depending only on vector momenta is extended to three-nucleon scattering. Starting from the spin-momentum dependence occurring as scalar products in two- and three-nucleon forces together with other scalar functions, we present the Faddeev multiple scattering series in which order by order the spin-degrees can be treated analytically leading to 3D integrations over scalar functions depending on momentum vectors only. Such formulation is especially important in view of awaiting extension of 3N Faddeev calculations to projectile energies above the pion production threshold and applications of chiral perturbation theory 3N forces, which are to be most efficiently treated directly in such three-dimensional formulation without having to expand these forces into a partial wave basis.

  15. Application of Simulated Three Dimensional CT Image in Orthognathic Surgery

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun Don; Park, Chang Seo [Dept. of Dental Radiology, College of Dentistry, Yensei University, Seoul (Korea, Republic of); Yoo, Sun Kook; Lee, Kyoung Sang [Dept. of Medical Engineering, College of Medicine, Yensei University, Seoul (Korea, Republic of)

    1998-08-15

    In orthodontics and orthognathic surgery, cephalogram has been routine practice in diagnosis and treatment evaluation of craniofacial deformity. But its inherent distortion of actual length and angles during projecting three dimensional object to two dimensional plane might cause errors in quantitative analysis of shape and size. Therefore, it is desirable that three dimensional object is diagnosed and evaluated three dimensionally and three dimensional CT image is best for three dimensional analysis. Development of clinic necessitates evaluation of result of treatment and comparison before and after surgery. It is desirable that patient that was diagnosed and planned by three dimensional computed tomography before surgery is evaluated by three dimensional computed tomography after surgery, too. But Because there is no standardized normal values in three dimension now and three dimensional Computed Tomography needs expensive equipment and because of its expenses and amount of exposure to radiation, limitations still remain to be solved in its application to routine practice. If postoperative three dimensional image is constructed by pre and postoperative lateral and postero-anterior cephalograms and preoperative three dimensional computed tomogram, pre and postoperative image will be compared and evaluated three dimensionally without three dimensional computed tomography after surgery and that will contribute to standardize normal values in three dimension. This study introduced new method that computer-simulated three dimensional image was constructed by preoperative three dimensional computed tomogram and pre and postoperative lateral and postero-anterior cephalograms, and for validation of new method, in four cases of dry skull that position of mandible was displaced and four patients of orthognathic surgery, computer-simulated three dimensional image and actual postoperative three dimensional image were compared. The results were as follows. 1. In four cases of

  16. 实时三维超声心动图评价冠心病患者经皮冠状动脉介入治疗后左心室收缩同步性及功能%Assessment of left ventricular systolic synchrony and systolic function by real-time three-dimensional echocardiography in patients with coronary artery disease after percutaneous coronary intervention

    Institute of Scientific and Technical Information of China (English)

    叶振盛; 欧宓; 陈斌; 郭薇

    2011-01-01

    Objective The left ventricular synchrony and systolic function were assessed in patients with coronary artery disease before and after percutaneous coronary intervention ( PCI ) by real-time three-dimensional echocardiography ( RT-3DE ). Methods A total of 20 healthy volunteers were performed RT-3DE,and twenty patients with coronary artery disease had RT-3DE before PCI. RT-3DE follow-up was performed 1 week after PCI in all patients with coronary artery disease. Full-volume imaging was recorded before and 1 week after PCI and the data was analyzed by Qlab 6. 0 Offline analysis software. A series of global and regional left ventricular volume curves were plotted. The parameters of left ventricular systolic function and regional left ventricular ejection fraction ( rLVEF )were calculated. The parameters of left ventricular synchrony: Tmsv-16-sd、 Tmsv-12-sd、Tmsv-16-dif、Tmsv-12-dif、Tmsv-16-sd%、Tmsv-12-sd%、Tmsv-16-dif%、Tmsv-12-dif% were obtained by offline analysis software. A paired student s t test was used to compare the dates of coronary artery disease before PCI versus follow-up. Independent-samples t test was used to compare the dates between control group and the group of coronary artery disease. Results All the systolic synchrony parameters Tmsv-16-sd, Tmsv-12-sd, Tmsv-16-dif, Tmsv-12-dif, Tmsv-16-sd% , Tmsv-12-sd% , Tmsv-16-dif% and Tmsv-12-dif% were significant larger in patients with coronary artery disease than those of the control group[( 149.2±15.7)ms vs ( 23. 8 ±20. 7 )ms,( 77. 5 ±63. 0 )ms vs ( 15. 6 ±21. 3 ) ms,( 308.0 ±198.8 )ms vs ( 81.9 ±73. 1 )ms, ( 227.2 ±193.8 )ms vs ( 65.6 ± 90.3)ms,( 10. 9 ±6. 3 )% vs ( 2. 6 ±2.4 )% , ( 32. 9 ±21. 9 )% vs ( 11. 2 ± 11.7)%, (24.1 ±22.1 )% vs(6.9 ±8.6)% ,t = -3.714 ~ -6. 588 ,P <0. 05]. After treated with PCI,the Tmsv-16-sd, Tmsv-12-sd, Tmsv-16-dif, Tmsv-12-dif ,Tmsv-16-sd% and Tmsv-16-dif% of coronary artery disease patients were lower than those before PCI[( 58. 8 ±50. 1 )ms vs ( 149

  17. Untethered micro-robotic coding of three-dimensional material composition

    Science.gov (United States)

    Tasoglu, S.; Diller, E.; Guven, S.; Sitti, M.; Demirci, U.

    2014-01-01

    Complex functional materials with three-dimensional micro- or nano-scale dynamic compositional features are prevalent in nature. However, the generation of three-dimensional functional materials composed of both soft and rigid microstructures, each programmed by shape and composition, is still an unsolved challenge. Here we describe a method to code complex materials in three-dimensions with tunable structural, morphological and chemical features using an untethered magnetic micro-robot remotely controlled by magnetic fields. This strategy allows the micro-robot to be introduced to arbitrary microfluidic environments for remote two- and three-dimensional manipulation. We demonstrate the coding of soft hydrogels, rigid copper bars, polystyrene beads and silicon chiplets into three-dimensional heterogeneous structures. We also use coded microstructures for bottom-up tissue engineering by generating cell-encapsulating constructs.

  18. Three-dimensional Spontaneous Magnetic Reconnection

    Science.gov (United States)

    Beresnyak, Andrey

    2017-01-01

    Magnetic reconnection is best known from observations of the Sun where it causes solar flares. Observations estimate the reconnection rate as a small, but non-negligible fraction of the Alfvén speed, so-called fast reconnection. Until recently, the prevailing pictures of reconnection were either of resistivity or plasma microscopic effects, which was contradictory to the observed rates. Alternative pictures were either of reconnection due to the stochasticity of magnetic field lines in turbulence or the tearing instability of the thin current sheet. In this paper we simulate long-term three-dimensional nonlinear evolution of a thin, planar current sheet subject to a fast oblique tearing instability using direct numerical simulations of resistive-viscous magnetohydrodynamics. The late-time evolution resembles generic turbulence with a ‑5/3 power spectrum and scale-dependent anisotropy, so we conclude that the tearing-driven reconnection becomes turbulent reconnection. The turbulence is local in scale, so microscopic diffusivity should not affect large-scale quantities. This is confirmed by convergence of the reconnection rate toward ∼ 0.015{v}{{A}} with increasing Lundquist number. In this spontaneous reconnection, with mean field and without driving, the dissipation rate per unit area also converges to ∼ 0.006ρ {v}{{A}}3, and the dimensionless constants 0.015 and 0.006 are governed only by self-driven nonlinear dynamics of the sheared magnetic field. Remarkably, this also means that a thin current sheet has a universal fluid resistance depending only on its length to width ratio and to {v}{{A}}/c.

  19. Three-dimensional, dynamic meteorology of Titan

    Science.gov (United States)

    Mitchell, J.; Adamkovics, M.; Caballero, R.; Turtle, E. P.; Arias, T.; Sayanagi, K. M.

    2011-12-01

    Titan exhibits an active weather cycle involving methane. Because of low insolation and a stabilizing antigreenhouse effect [McKay et al. 1989], moist convection on Titan cannot be maintained purely through surface evaporative fluxes, indicating that moisture convergence provided by large-scale modes of circulation is important for convective cloud formation [e.g., Mitchell et al. 2006; Barth & Rafkin 2010]. Recent Cassini Imaging Science Subsystem (ISS) images of Titan have revealed large-scale clouds with an interesting array of morphologies and characteristics. Most strikingly, an arrow-shaped cloud oriented eastward was observed at the equator on 27 September 2010 [Turtle et al. 2011a], followed by observations of surface wetting which gradually diminished over several months [Turtle et al. 2011b]. We demonstrate a process for the physical interpretation of individual observed storms and their aggregate effect on surface erosion through a combined analysis of cloud observations and simulations [Mitchell et al. in press]. We show that planetary-scale Kelvin waves naturally arising in a new, three-dimensional version of our Titan general circulation model (GCM) robustly organize convection into chevron-shaped storms at Titan's equator during the current season, as observed. The phasing of this mode with another, much slower one causes a 20-fold increase in precipitation rates over the average, each producing up to several centimeters of precipitation over 1000-km-scale regions, with important implications for observed fluvial features [Langhans et al. 2011]. Our initial results indicate an essential role for planetary-scale atmospheric waves in organizing Titan's methane weather. I will discuss prospects for extending our analysis to other Titan observations.

  20. Measurements using three-dimensional product imaging

    Directory of Open Access Journals (Sweden)

    A. Sioma

    2010-07-01

    Full Text Available This article discusses a method of creating a three-dimensional cast model using vision systems and how that model can be used in thequality assessment process carried out directly on the assembly line. The technology of active vision, consisting in illumination of theobject with a laser beam, was used to create the model. Appropriate configuration of camera position geometry and laser light allows thecollection of height profiles and construction of a 3D model of the product on their basis. The article discusses problems connected with the resolution of the vision system, resolution of the laser beam analysis, and resolution connected with the application of the successive height profiles on sample cast planes. On the basis of the model, measurements allowing assessment of dimension parameters and surface defects of a given cast are presented. On the basis of tests and analyses of such a threedimensional cast model, a range of checks which are possible to conduct using 3D vision systems is indicated.Testing casts using that technology allows rapid assessment of selected parameters. Construction of the product’s model and dimensional assessment take a few seconds, which significantly reduces the duration of checks in the technological process. Depending on the product, a few checks may be carried out simultaneously on the product’s model.The possibility of controlling all outgoing products, and creating and modifying the product parameter control program, makes the solutionhighly flexible, which is confirmed by pilot industrial implementations. The technology will be developed in terms of detection andidentification of surface defects. It is important due to the possibility of using such information for the purposes of selecting technologicalprocess parameters and observing the effect of changes in selected parameters on the cast parameter controlled in a vision system.

  1. Three-dimensional kinematics of hummingbird flight.

    Science.gov (United States)

    Tobalske, Bret W; Warrick, Douglas R; Clark, Christopher J; Powers, Donald R; Hedrick, Tyson L; Hyder, Gabriel A; Biewener, Andrew A

    2007-07-01

    Hummingbirds are specialized for hovering flight, and substantial research has explored this behavior. Forward flight is also important to hummingbirds, but the manner in which they perform forward flight is not well documented. Previous research suggests that hummingbirds increase flight velocity by simultaneously tilting their body angle and stroke-plane angle of the wings, without varying wingbeat frequency and upstroke: downstroke span ratio. We hypothesized that other wing kinematics besides stroke-plane angle would vary in hummingbirds. To test this, we used synchronized high-speed (500 Hz) video cameras and measured the three-dimensional wing and body kinematics of rufous hummingbirds (Selasphorus rufus, 3 g, N=5) as they flew at velocities of 0-12 m s(-1) in a wind tunnel. Consistent with earlier research, the angles of the body and the stroke plane changed with velocity, and the effect of velocity on wingbeat frequency was not significant. However, hummingbirds significantly altered other wing kinematics including chord angle, angle of attack, anatomical stroke-plane angle relative to their body, percent of wingbeat in downstroke, wingbeat amplitude, angular velocity of the wing, wingspan at mid-downstroke, and span ratio of the wingtips and wrists. This variation in bird-centered kinematics led to significant effects of flight velocity on the angle of attack of the wing and the area and angles of the global stroke planes during downstroke and upstroke. We provide new evidence that the paths of the wingtips and wrists change gradually but consistently with velocity, as in other bird species that possess pointed wings. Although hummingbirds flex their wings slightly at the wrist during upstroke, their average wingtip-span ratio of 93% revealed that they have kinematically ;rigid' wings compared with other avian species.

  2. [Three-dimensional reconstruction of heart valves].

    Science.gov (United States)

    Flachskampf, F A; Kühl, H; Franke, A; Frielingsdorf, J; Klues, H; Krebs, W; Hanrath, P

    1995-08-01

    The reconstruction of three-dimensional data sets from two-dimensional echocardiographic images offers several fundamental advantages: 1. more complete data than present in the few standard 2D-view; 2. off-line generation of any desired plane, cut, or perspective after the data set has been acquired; 3. access to quantitative parameters like surface areas (e.g., of valve leaflets or portions of leaflets), volumes, and others, without geometric assumptions. The mitral valve has been the focus of several studies using various techniques of reconstruction of transthoracic or transesophageal images. These studies have shown the mitral annulus to be a non-planar, "saddle-shaped" structure, with an average distance of highest to lowest points of 14 mm in normals. This recognition of mitral annular non-planarity has led to a more stringent echocardiographic definition of mitral valve prolapse. Further studies have shown systolic shrinkage of mitral annular area by about 30% and systolic apico-basal translation of the annulus by approximately 1 cm in normals. In patients with dilated cardiomyopathy, the annulus is flattened, and both cyclic change in annular area and apico-basal translation are significantly reduced. 3D-studies of the left ventricular outflow tract in hypertrophic obstructive cardiomyopathy allow measurement of outflow tract and leaflet surface areas and dynamic spatial visualization of systolic anterior motion of the anterior mitral leaflet. Automated techniques to reconstruct the full grey value data set from a high number of parallel or rotational transesophageal planes allow impressive visualization of normal and diseased mitral and aortic valves or valve prostheses, with special emphasis on generating "surgical" views and perspectives, which cannot be obtained by conventional tomographic imaging.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. Airway branching morphogenesis in three dimensional culture

    Directory of Open Access Journals (Sweden)

    Gudjonsson Thorarinn

    2010-11-01

    Full Text Available Abstract Background Lungs develop from the fetal digestive tract where epithelium invades the vascular rich stroma in a process called branching morphogenesis. In organogenesis, endothelial cells have been shown to be important for morphogenesis and the maintenance of organ structure. The aim of this study was to recapitulate human lung morphogenesis in vitro by establishing a three dimensional (3D co-culture model where lung epithelial cells were cultured in endothelial-rich stroma. Methods We used a human bronchial epithelial cell line (VA10 recently developed in our laboratory. This cell line cell line maintains a predominant basal cell phenotype, expressing p63 and other basal markers such as cytokeratin-5 and -14. Here, we cultured VA10 with human umbilical vein endothelial cells (HUVECs, to mimic the close interaction between these cell types during lung development. Morphogenesis and differentiation was monitored by phase contrast microscopy, immunostainings and confocal imaging. Results We found that in co-culture with endothelial cells, the VA10 cells generated bronchioalveolar like structures, suggesting that lung epithelial branching is facilitated by the presence of endothelial cells. The VA10 derived epithelial structures display various complex patterns of branching and show partial alveolar type-II differentiation with pro-Surfactant-C expression. The epithelial origin of the branching VA10 colonies was confirmed by immunostaining. These bronchioalveolar-like structures were polarized with respect to integrin expression at the cell-matrix interface. The endothelial-induced branching was mediated by soluble factors. Furthermore, fibroblast growth factor receptor-2 (FGFR-2 and sprouty-2 were expressed at the growing tips of the branching structures and the branching was inhibited by the FGFR-small molecule inhibitor SU5402. Discussion In this study we show that a human lung epithelial cell line can be induced by endothelial cells to

  4. Three-dimensional nonlinear acoustical holography

    Science.gov (United States)

    Niu, Yaying

    Nearfield Acoustical Holography (NAH) is an acoustic field visualization technique that can be used to reconstruct three-dimensional (3-D) acoustic fields by projecting two-dimensional (2-D) data measured on a hologram surface. However, linear NAH algorithms developed and improved by many researchers can result in significant reconstruction errors when they are applied to reconstruct 3-D acoustic fields that are radiated from a high-level noise source and include significant nonlinear components. Here, planar, nonlinear acoustical holography procedures are developed that can be used to reconstruct 3-D, nonlinear acoustic fields radiated from a high-level noise source based on 2-D acoustic pressure data measured on a hologram surface. The first nonlinear acoustic holography procedure is derived for reconstructing steady-state acoustic pressure fields by applying perturbation and renormalization methods to nonlinear, dissipative, pressure-based Westervelt Wave Equation (WWE). The nonlinear acoustic pressure fields radiated from a high-level pulsating sphere and an infinite-size, vibrating panel are used to validate this procedure. Although the WWE-based algorithm is successfully validated by those two numerical simulations, it still has several limitations: (1) Only the fundamental frequency and its second harmonic nonlinear components can be reconstructed; (2) the application of this algorithm is limited to mono-frequency source cases; (3) the effects of bent wave rays caused by transverse particle velocities are not included; (4) only acoustic pressure fields can be reconstructed. In order to address the limitations of the steady-state, WWE-based procedure, a transient, planar, nonlinear acoustic holography algorithm is developed that can be used to reconstruct 3-D nonlinear acoustic pressure and particle velocity fields. This procedure is based on Kuznetsov Wave Equation (KWE) that is directly solved by using temporal and spatial Fourier Transforms. When compared

  5. Value of three-dimensional speckle-tracking in detecting left ventricular dysfunction in patients with aortic valvular diseases.

    Science.gov (United States)

    Li, Chun-mei; Li, Chen; Bai, Wen-juan; Zhang, Xiao-ling; Tang, Hong; Qing, Zhang; Li, Rao

    2013-11-01

    The aim of this study was to investigate the value of three-dimensional speckle-tracking echocardiography for the detection of subclinical left ventricular dysfunction in patients with aortic valvular disease (AVD). Fifty-nine patients with AVD in New York Heart Association functional class I or II as well as 48 controls were recruited. Patients with AVD were divided further into those with aortic stenosis (AS; n = 34) and those with aortic regurgitation (AR; n = 25). All patients underwent conventional echocardiography and three-dimensional speckle-tracking echocardiography. Analysis of variance showed global longitudinal strain to be compromised in the AR group (-16.9% vs -19.3%, P = .015) and more dramatically decreased in the AS group (-14.3% vs -19.3%, P speckle-tracking echocardiography are useful indices of early-stage heart dysfunction caused by AVD. Longitudinal strain is more vulnerable to pressure overload caused by AS, whereas circumferential strain is more sensitive to volume overload due to AR. Published by Mosby, Inc.

  6. The Three-dimensional Digital Factory for Shipbuilding Technology Research

    Directory of Open Access Journals (Sweden)

    Xu Wei

    2016-01-01

    Full Text Available The three-dimensional digital factory technology research is the hotspot in shipbuilding recently. The three-dimensional digital factory technology not only focus on design the components of the product, but also discuss on the simulation and analyses of the production process.Based on the three-dimensional model, the basic data layer, application control layer and the presentation layer of hierarchical structure are established in the three-dimensional digital factory of shipbuilding in this paper. And the key technologies of three-dimensional digital factory of shipbuilding are analysed. Finally, a case study is applied and the results show that the three-dimensional digital factory will play an important role in the future.

  7. Three-dimensional decomposition method of global atmospheric circulation

    Institute of Scientific and Technical Information of China (English)

    LIU HaiTao; HU ShuJuan; XU Ming; CHOU JiFan

    2008-01-01

    By adopting the idea of three-dimensional Walker, Hadley and Rossby stream functions, the global atmospheric circulation can be considered as the sum of three stream functions from a global perspective. Therefore, a mathematical model of three-dimensional decomposition of global atmospheric circulation is proposed and the existence and uniqueness of the model are proved. Besides, the model includes a numerical method leading to no truncation error in the discrete three-dimensional grid points. Results also show that the three-dimensional stream functions exist and are unique for a given velocity field. The mathematical model shows the generalized form of three-dimensional stream functions equal to the velocity field in representing the features of atmospheric motion. Besides, the vertical velocity calculated through the model can represent the main characteristics of the vertical motion. In sum, the three-dimensional decomposition of atmospheric circulation is convenient for the further investigation of the features of global atmospheric motions.

  8. Three-dimensional carbon nanotube based photovoltaics

    Science.gov (United States)

    Flicker, Jack

    2011-12-01

    Photovoltaic (PV) cells with a three dimensional (3D) morphology are an exciting new research thrust with promise to create cheaper, more efficient solar cells. This work introduces a new type of 3D PV device based on carbon nanotube (CNT) arrays. These arrays are paired with the thin film heterojunction, CdTe/CdS, to form a complete 3D carbon nanotube PV device (3DCNTPV). Marriage of a complicated 3D structure with production methods traditionally used for planar CdTe solar cell is challenging. This work examines the problems associated with processing these types of cells and systematically alters production methods of the semiconductor layers and electrodes to increase the short circuit current (Isc), eliminate parasitic shunts, and increase the open circuit voltage (Voc). The main benefit of 3D solar cell is the ability to utilize multiple photon interactions with the solar cell surface. The three dimensionality allows photons to interact multiple times with the photoactive material, which increases the absorption and the overall power output over what is possible with a two dimensional (2D) morphology. To quantify the increased power output arising from these multiple photon interactions, a new absorption efficiency term, eta3D, is introduced. The theoretical basis behind this new term and how it relates to the absorption efficiency of a planar cell, eta 2D, is derived. A unique model for the average number of multiple photon impingements, Gamma, is proposed based on three categories of 3D morphology: an infinite trench, an enclosed box, and an array of towers. The derivation of eta3D and Gamma for these 3D PV devices gives a complete picture of the enhanced power output over 2D cells based on CNT array height, pitch, radius, and shape. This theory is validated by monte carlo simulations and experiment. This new type of 3D PV devices has been shown to work experimentally. The first 3DCNTPV cells created posses Isc values of 0.085 to 17.872mA/cm2 and Voc values

  9. Intracardiac echocardiography.

    Science.gov (United States)

    Bruce, C J; Friedman, P A

    2002-10-01

    This article describes currently available intracardiac ultrasound (ICE) technology contrasting it with intravascular ultrasound (IVUS) highlighting their differences. Clinical applications in the electrophysiologic and cardiac catheterization laboratory are discussed and current limitations addressed. Intracardiac echocardiography (ICE) is possible because lower frequency transducers (in contrast to higher frequency IVUS devices) have been miniaturized and mounted onto catheters capable of percutaneous insertion into the heart. These lower frequency transducers are capable of enhanced tissue penetration, permitting high-resolution 2D "whole heart" imaging. Also, with the introduction of the newest phased array transducer, Doppler hemodynamic data in addition to high resolution imaging can also be obtained. ICE facilitates electrophysiologic procedures by guiding transseptal catheterization, enabling endocardial anatomy visualization and targeting of arrhythmogenic substrate, ensuring optimal ablation electrode/tissue contact and promptly diagnosing procedural complications. Promising non-electrophysiologic applications include guidance of percutaneous closure of septal defects, percutaneous mitral balloon valvuloplasty and complex cardiac biopsy. Current limitations include monoplanar imaging, narrow field of view, and relatively large size of the catheter. Intra-cardiac imaging is now a clinical tool and has the potential to play an important role in diagnostic and therapeutic interventional procedures. Further refinement and miniaturization of these transducers, through continued technological progress, will make way for primary operator controlled, integrated ultrasound-guided interventional devices.

  10. Three-Dimensional Gear Crack Propagation Studied

    Science.gov (United States)

    Lewicki, David G.

    1999-01-01

    Gears used in current helicopters and turboprops are designed for light weight, high margins of safety, and high reliability. However, unexpected gear failures may occur even with adequate tooth design. To design an extremely safe system, the designer must ask and address the question, "What happens when a failure occurs?" With gear-tooth bending fatigue, tooth or rim fractures may occur. A crack that propagates through a rim will be catastrophic, leading to disengagement of the rotor or propeller, loss of an aircraft, and possible fatalities. This failure mode should be avoided. A crack that propagates through a tooth may or may not be catastrophic, depending on the design and operating conditions. Also, early warning of this failure mode may be possible because of advances in modern diagnostic systems. One concept proposed to address bending fatigue fracture from a safety aspect is a splittooth gear design. The prime objective of this design would be to control crack propagation in a desired direction such that at least half of the tooth would remain operational should a bending failure occur. A study at the NASA Lewis Research Center analytically validated the crack-propagation failsafe characteristics of a split-tooth gear. It used a specially developed three-dimensional crack analysis program that was based on boundary element modeling and principles of linear elastic fracture mechanics. Crack shapes as well as the crack-propagation life were predicted on the basis of the calculated stress intensity factors, mixed-mode crack-propagation trajectory theories, and fatigue crack-growth theories. The preceding figures show the effect of the location of initial cracks on crack propagation. Initial cracks in the fillet of the teeth produced stress intensity factors of greater magnitude (and thus, greater crack growth rates) than those in the root or groove areas of the teeth. Crack growth was simulated in a case study to evaluate crack-propagation paths. Tooth

  11. Three-dimensional simulations of resistance spot welding

    DEFF Research Database (Denmark)

    Nielsen, Chris Valentin; Zhang, Wenqi; Perret, William

    2014-01-01

    This paper draws from the fundamentals of electro-thermo-mechanical coupling to the main aspects of finite element implementation and three-dimensional modelling of resistance welding. A new simulation environment is proposed in order to perform three-dimensional simulations and optimization of r...

  12. Three-dimensional Reciprocal Structures: Morphology, Concepts, Generative Rules

    DEFF Research Database (Denmark)

    Parigi, Dario; Pugnale, Alberto

    2012-01-01

    This paper present seven different three dimensional structures based on the principle of structural reciprocity with superimposition joint and standardized un-notched elements. Such typology could be regarded as being intrinsically three-dimensional because elements sit one of the top of the oth...

  13. Collapse in a forced three-dimensional nonlinear Schrodinger equation

    DEFF Research Database (Denmark)

    Lushnikov, P.M.; Saffman, M.

    2000-01-01

    We derive sufficient conditions for the occurrence of collapse in a forced three-dimensional nonlinear Schrodinger equation without dissipation. Numerical studies continue the results to the case of finite dissipation.......We derive sufficient conditions for the occurrence of collapse in a forced three-dimensional nonlinear Schrodinger equation without dissipation. Numerical studies continue the results to the case of finite dissipation....

  14. Synthetic Spectrum Methods for Three-Dimensional Supernova Models

    CERN Document Server

    Thomas, R C

    2003-01-01

    Current observations stimulate the production of fully three-dimensional explosion models, which in turn motivates three-dimensional spectrum synthesis for supernova atmospheres. We briefly discuss techniques adapted to address the latter problem, and consider some fundamentals of line formation in supernovae without recourse to spherical symmetry. Direct and detailed extensions of the technique are discussed, and future work is outlined.

  15. Semifolded Localized Structures in Three-Dimensional Soliton Systems

    Institute of Scientific and Technical Information of China (English)

    FANG Jian-Ping; ZHENG Chun-Long; CHEN Li-Qun

    2004-01-01

    By means ora Painlevé-Backlund transformation and a multi-linear variable separation approach, abundant localized coherent excitations of the three-dimensional Broer-Kaup-Kupershmidt system with variable coefficients are derived. There are possible phase shifts for the interactions of the three-dimensional novel localized structures discussed in this paper.

  16. Semifolded Localized Structures in Three-Dimensional Soliton Systems

    Institute of Scientific and Technical Information of China (English)

    FANGJian-Ping; ZHENGChun-Long; CHENLi-Qun

    2004-01-01

    By means ofa Painlev6 Backlund transformation and a multi-linear variable separation approach, abundant localized coherent excitations of the three-dimensional Broer Kaup Kupershmidt system with variable coeft~cients are derived. There are possible phase shifts for the interactions of the three-dimensional novel localized structures discussed in this paper.

  17. Computer-Generated, Three-Dimensional Character Animation.

    Science.gov (United States)

    Van Baerle, Susan Lynn

    This master's thesis begins by discussing the differences between 3-D computer animation of solid three-dimensional, or monolithic, objects, and the animation of characters, i.e., collections of movable parts with soft pliable surfaces. Principles from two-dimensional character animation that can be transferred to three-dimensional character…

  18. The relation between temporal and spatial stability in three-dimensional flows

    Science.gov (United States)

    Nayfeh, A. H.; Padhye, A.

    1978-01-01

    An analysis is presented of the nonparallel spatial or temporal stability of three-dimensional incompressible, isothermal boundary-layer flows taking into account the transverse velocity component as well as the axial and crossflow variations of the mean flow. The method of multiple scales is used to derive partial differential equations that describe the axial and crossflow variations of the disturbance amplitude, phase and wavenumbers. This equation is used to derive the expressions that relate the temporal and spatial instabilities. These relations are functions of the complex group velocities. Moreover, this equation is used to derive the expression that relates the spatial amplification in any direction to a calculated amplification in any other direction. These relations are verified by numerical results obtained for two- and three-dimensional disturbances in two- and three-dimensional flows.

  19. Three dimensional periodic foundations for base seismic isolation

    Science.gov (United States)

    Yan, Y.; Cheng, Z.; Menq, F.; Mo, Y. L.; Tang, Y.; Shi, Z.

    2015-07-01

    Based on the concept of phononic crystals, periodic foundations made of periodic materials are investigated in this paper. The periodic foundations can provide low frequency band gaps, which cover the main frequency ranges of seismic waves. Therefore, the periodic foundations are able to protect the upper structures during earthquake events. In this paper, the basic theory of three dimensional periodic foundations is studied and the finite element method was used to conduct the sensitivity study. A simplified three-dimensional periodic foundation with a superstructure was tested in the field and the feasibility of three dimensional periodic foundations was proved. The test results showed that the response of the upper structure with the three dimensional periodic foundation was reduced under excitation waves with the main frequency falling in the attenuation zones. The finite element analysis results are consistent with the experimental data, indicating that three dimensional periodic foundations are a feasible way of reducing seismic vibrations.

  20. Virtual three-dimensional blackboard: three-dimensional finger tracking with a single camera.

    Science.gov (United States)

    Wu, Andrew; Hassan-Shafique, Khurram; Shah, Mubarak; da Vitoria Lobo, N

    2004-01-10

    We present a method for three-dimensional (3D) tracking of a human finger from a monocular sequence of images. To recover the third dimension from the two-dimensional images, we use the fact that the motion of the human arm is highly constrained owing to the dependencies between elbow and forearm and the physical constraints on joint angles. We use these anthropometric constraints to derive a 3D trajectory of a gesticulating arm. The system is fully automated and does not require human intervention. The system presented can be used as a visualization tool, as a user-input interface, or as part of some gesture-analysis system in which 3D information is important.

  1. American Society of Echocardiography

    Science.gov (United States)

    American Society of Echocardiography Join Ase Member Portal Log In Membership Member Portal Log In Join ASE Renew Benefits Rates FASE – Fellow of the American Society of Echocardiography Member Referral Program FAQs Initiatives Advocacy ...

  2. Robust three dimensional surface contouring method with digital holography

    Institute of Scientific and Technical Information of China (English)

    YUAN Cao-jin; ZHAI Hong-chen; WANG Xiao-lei; WU Lan

    2006-01-01

    In this paper,a digital holography system with short-coherence light source is used to record a series of holograms of a micro-object. The three dimensional reconstruction is completed by the least-square-polynomial-fitting with a series of two dimensional intensity images which are obtained through holographic reconstruction. This three dimensional reconstruction method can be used to carry out three-dimensional reconstruction of a micro-object with strong laser speckle noise,which can not be obtained from the conventional method.

  3. Cylindrical Three-Dimensional Porous Anodic Alumina Networks

    Directory of Open Access Journals (Sweden)

    Pedro M. Resende

    2016-11-01

    Full Text Available The synthesis of a conformal three-dimensional nanostructure based on porous anodic alumina with transversal nanopores on wires is herein presented. The resulting three-dimensional network exhibits the same nanostructure as that obtained on planar geometries, but with a macroscopic cylindrical geometry. The morphological analysis of the nanostructure revealed the effects of the initial defects on the aluminum surface and the mechanical strains on the integrity of the three-dimensional network. The results evidence the feasibility of obtaining 3D porous anodic alumina on non-planar aluminum substrates.

  4. Three Dimensional Topological Field Theory induced from Generalized Complex Structure

    CERN Document Server

    Ikeda, N

    2004-01-01

    We construct a three-dimensional topological sigma model which is induced from a generalized complex structure on a target generalized complex manifold. This model is constructed from maps from a three-dimensional manifold $X$ to an arbitrary generalized complex manifold $M$. The theory is invariant under the diffeomorphism on the world volume and the $b$-transformation on the generalized complex structure. Moreover the model is manifestly invariant under the mirror symmetry. We derive from this model the Zucchini's two dimensional topological sigma model with a generalized complex structure as a boundary action on $\\partial X$. As a special case, we obtain three dimensional realization of a WZ-Poisson manifold.

  5. Protein conformation in solution by three-dimensional fluorescence spectrometry

    Institute of Scientific and Technical Information of China (English)

    鄢远; 许金钩; 陈国珍

    1996-01-01

    The conformations of bovine serum albumin (USA) and egg albumin (EA) in solution and their conformation changes under different conditions were studied by using three-dimensional fluorescence spectrometry (TDFS) such as three-dimensional fluorescence (TDF) spectra and three-dimensional fluorescence polarization (TDFP) spectra with tryptophan residues in protein molecules as an intrinsic fluorescent probe. The results show that the microenvironment of tryptophan residues of protein molecules in various solutions can be directly indicated and TDFS is an effective tool for studying protein conformation in solution. Meantime, some valuable results were obtained.

  6. DEVELOPMENT OF A HYBRID MODEL FOR THREE-DIMENSIONAL GIS

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    This paper presents a hybrid model for three-dimensional Geographical Information Systems which is an integration of surface- and volume-based models. The Triangulat ed Irregular Network (TIN) and octree models are integrated in this hybrid model. The TIN model works as a surface-based model which mainly serves for surface presentation and visualization. On the other hand, the octree encoding supports volumetric analysis. The designed data structure brings a major advantage in the three-dimensional selective retrieval. This technique increases the efficiency of three-dimensional data operation.

  7. Three-dimensional imaging of hidden objects using positron emission backscatter

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dongwon [Los Alamos National Laboratory; Cowee, Misa [Los Alamos National Laboratory; Fenimore, Ed [Los Alamos National Laboratory; Galassi, Mark [Los Alamos National Laboratory; Looker, Quinn [Los Alamos National Laboratory; Mcneil, Wendy V [Los Alamos National Laboratory; Stonehill, Laura [Los Alamos National Laboratory; Wallace, Mark [Los Alamos National Laboratory

    2009-01-01

    Positron emission backscatter imaging is a technique for interrogation and three-dimensional (3-D) reconstruction of hidden objects when we only have access to the objects from one side. Using time-of-flight differences in detected direct and backscattered positron-emitted photons, we construct 3-D images of target objects. Recently at Los Alamos National Laboratory, a fully three-dimensional imaging system has been built and the experimental results are discussed in this paper. Quantitative analysis of images reconstructed in both two- and three-dimensions are also presented.

  8. The Effects of Turbulence on Three-Dimensional Magnetic Reconnection at the Magnetopause

    CERN Document Server

    Price, L; Drake, J F; Cassak, P A; Dahlin, J; Ergun, R E

    2016-01-01

    Two- and three-dimensional particle-in-cell simulations of a recent encounter of the Magnetospheric Multiscale Mission (MMS) with an electron diffusion region at the magnetopause are presented. While the two-dimensional simulations are laminar, in the three-dimensional simulation turbulence develops at both the x-line and along the magnetic separatrices. The turbulence is strong enough to make the magnetic field around the reconnection island chaotic and produces both anomalous resistivity and anomalous viscosity. Each contribute significantly to breaking the frozen-in condition in the electron diffusion region. A surprise is that the crescent-shaped features seen in velocity distributions during the recent MMS observations and in two-dimensional simulations survive even in the turbulent environment of the three-dimensional system. This suggests that MMS's measurements of crescent distributions do not exclude the possibility that turbulence plays an important role in magnetopause reconnection.

  9. Anisotropic interpolation method of silicon carbide oxidation growth rates for three-dimensional simulation

    Science.gov (United States)

    Šimonka, Vito; Nawratil, Georg; Hössinger, Andreas; Weinbub, Josef; Selberherr, Siegfried

    2017-02-01

    We investigate anisotropical and geometrical aspects of hexagonal structures of Silicon Carbide and propose a direction dependent interpolation method for oxidation growth rates. We compute three-dimensional oxidation rates and perform one-, two-, and three-dimensional simulations for 4H- and 6H-Silicon Carbide thermal oxidation. The rates of oxidation are computed according to the four known growth rate values for the Si- (0 0 0 1) , a- (1 1 2 bar 0) , m- (1 1 bar 0 0) , and C-face (0 0 0 1 bar) . The simulations are based on the proposed interpolation method together with available thermal oxidation models. We additionally analyze the temperature dependence of Silicon Carbide oxidation rates for different crystal faces using Arrhenius plots. The proposed interpolation method is an essential step towards highly accurate three-dimensional oxide growth simulations which help to better understand the anisotropic nature and oxidation mechanism of Silicon Carbide.

  10. Interactive dynamic three-dimensional scene for the ground-based three-dimensional display

    Science.gov (United States)

    Hou, Peining; Sang, Xinzhu; Guo, Nan; Chen, Duo; Yan, Binbin; Wang, Kuiru; Dou, Wenhua; Xiao, Liquan

    2016-10-01

    Three-dimensional (3D) displays provides valuable tools for many fields, such as scientific experiment, education, information transmission, medical imaging and physical simulation. Ground based 360° 3D display with dynamic and controllable scene can find some special applications, such as design and construction of buildings, aeronautics, military sand table and so on. It can be utilized to evaluate and visualize the dynamic scene of the battlefield, surgical operation and the 3D canvas of art. In order to achieve the ground based 3D display, the public focus plane should be parallel to the camera's imaging planes, and optical axes should be offset to the center of public focus plane in both vertical and horizontal directions. Virtual cameras are used to display 3D dynamic scene with Unity 3D engine. Parameters of virtual cameras for capturing scene are designed and analyzed, and locations of virtual cameras are determined by the observer's eye positions in the observing space world. An interactive dynamic 3D scene for ground based 360° 3D display is demonstrated, which provides high-immersion 3D visualization.

  11. Surgical accuracy of three-dimensional virtual planning

    DEFF Research Database (Denmark)

    Stokbro, Kasper; Aagaard, Esben; Torkov, Peter

    2016-01-01

    This retrospective study evaluated the precision and positional accuracy of different orthognathic procedures following virtual surgical planning in 30 patients. To date, no studies of three-dimensional virtual surgical planning have evaluated the influence of segmentation on positional accuracy ...

  12. Direct Linear Transformation Method for Three-Dimensional Cinematography

    Science.gov (United States)

    Shapiro, Robert

    1978-01-01

    The ability of Direct Linear Transformation Method for three-dimensional cinematography to locate points in space was shown to meet the accuracy requirements associated with research on human movement. (JD)

  13. Study on three-dimensional freehand stroke creation

    Directory of Open Access Journals (Sweden)

    Cuixian Xuan

    2015-05-01

    Full Text Available The automotive frames that can be created consciously with three-dimensional freehand strokes are quite important and useful in the early stage of automotive styling. However, all the strokes are drawn on the screen in two-dimensional. This study focuses on the creation of three-dimensional freehand strokes by applying the interpolation algorithm in two orthogonal planes, the projection algorithm and the resultant matrix algorithm. The fitting algorithms of strokes have been developed as the bridges between the traditional two-dimensional sketching and three-dimensional digital modeling. The stylists could use the digital tablet and pen to sketch the frames or outlines of a vehicle in three-dimensional space and then those could be used for establishing the automotive surfaces in any engineering software.

  14. Three-Dimensional Measurement and Reconstruction of Fabric Drape Shape

    Institute of Scientific and Technical Information of China (English)

    SHEN Yi; YIN Hong-yuan; LIU Xuan-mu

    2007-01-01

    This paper introduces a new method of measuring the three-dimensional drape shape of fabrics with structural light. First, we apply parallel annular structural light to form light and shade alternating contour stripes on the surface of fabrics. We then collect the images of contour stripes using Charge Coupled Device (CCD). Subsequently, we process the images to identify the contour stripes and edges of fabrics, and obtain the fabric contour lines of curved surfaces. Finally, we apply three-dimensional curved surface modeling method based on a network of polar coordinates, and reconstruct the three-dimensional drape shape of fabrics. Experiments show that our method is effective in testing and reconstructing three-dimensional drape shape of fabrics.

  15. Three-dimensional reconstruction of functional brain images

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Masato; Shoji, Kazuhiko; Kojima, Hisayoshi; Hirano, Shigeru; Naito, Yasushi; Honjo, Iwao [Kyoto Univ. (Japan)

    1999-08-01

    We consider PET (positron emission tomography) measurement with SPM (Statistical Parametric Mapping) analysis to be one of the most useful methods to identify activated areas of the brain involved in language processing. SPM is an effective analytical method that detects markedly activated areas over the whole brain. However, with the conventional presentations of these functional brain images, such as horizontal slices, three directional projection, or brain surface coloring, makes understanding and interpreting the positional relationships among various brain areas difficult. Therefore, we developed three-dimensionally reconstructed images from these functional brain images to improve the interpretation. The subjects were 12 normal volunteers. The following three types of images were constructed: routine images by SPM, three-dimensional static images, and three-dimensional dynamic images, after PET images were analyzed by SPM during daily dialog listening. The creation of images of both the three-dimensional static and dynamic types employed the volume rendering method by VTK (The Visualization Toolkit). Since the functional brain images did not include original brain images, we synthesized SPM and MRI brain images by self-made C++ programs. The three-dimensional dynamic images were made by sequencing static images with available software. Images of both the three-dimensional static and dynamic types were processed by a personal computer system. Our newly created images showed clearer positional relationships among activated brain areas compared to the conventional method. To date, functional brain images have been employed in fields such as neurology or neurosurgery, however, these images may be useful even in the field of otorhinolaryngology, to assess hearing and speech. Exact three-dimensional images based on functional brain images are important for exact and intuitive interpretation, and may lead to new developments in brain science. Currently, the surface

  16. Stability of compressible three-dimensional boundary-layer flows

    Science.gov (United States)

    Reed, H. L.; Nayfeh, A. H.

    1982-01-01

    For compressible three-dimensional flow, the method of multiple scales to formulate the three-dimensional stability problem and determine the partial-differential equations governing variations of the amplitude and complex wavenumbers is used. A method for following one specific wave along its trajectory to ascertain the characteristics of the most unstable disturbance is proposed. Numerical results using the flow over the X-21 wing as calculated from the Kaups-Cebeci code will be presented.

  17. Alignment-free three-dimensional optical metamaterials.

    Science.gov (United States)

    Zhao, Yang; Shi, Jinwei; Sun, Liuyang; Li, Xiaoqin; Alù, Andrea

    2014-03-05

    Three-dimensional optical metamaterials based on multilayers typically rely on critical vertical alignment to achieve the desired functionality. Here the conditions under which three-dimensional metamaterials with different functionalities may be realized without constraints on alignment are analyzed and demonstrated experimentally. This study demonstrates that the release of alignment constraints for multilayered metamaterials is allowed, while their anomalous interaction with light is preserved. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Three-dimensional visualization and animation for power systems analysis

    Energy Technology Data Exchange (ETDEWEB)

    Milano, Federico [Department of Electrical Engineering of the University of Castilla-La Mancha, 13071, Ciudad Real (Spain)

    2009-12-15

    This paper describes a novel approach for three-dimensional visualization and animation of power systems analyses. The paper demonstrates that three-dimensional visualization of power systems can be used for teaching and can help in easily understanding complex concepts. The solutions of power flow analysis, continuation power flow, optimal power flow and time domain simulations are used for illustrating the proposed technique. The paper presents a variety of examples, particularly oriented to education and practitioner training. Conclusions are duly drawn. (author)

  19. Three-dimensional network of Drosophila brain hemisphere

    OpenAIRE

    Mizutani, Ryuta; Saiga, Rino; Takeuchi, Akihisa; Uesugi, Kentaro; Suzuki, Yoshio

    2016-01-01

    The first step to understanding brain function is to determine the brain's network structure. We report a three-dimensional analysis of the brain network of the fruit fly Drosophila melanogaster by synchrotron-radiation tomographic microscopy. A skeletonized wire model of the left half of the brain network was built by tracing the three-dimensional distribution of X-ray absorption coefficients. The obtained models of neuronal processes were classified into groups on the basis of their three-d...

  20. Three-dimensional study of the multi-cavity FEL

    Energy Technology Data Exchange (ETDEWEB)

    Krishnagopal, S.; Kumar, V. [Centre for Advanced Technology, Indore (India)

    1995-12-31

    The Multi-Cavity Free-Electron Laser has been proposed earlier, as a new configuration to obtain short, intense pulses of radiation, the key idea being to pre-bunch the electron beam in a number of very short cavities. Those studies were one-dimensional. Here we use three-dimensional simulations to study the viability of this concept when three-dimensional effects are included, particularly with regard to the transverse modes of the optical beam.

  1. Uniform Deterministic Discrete Method for Three Dimensional Systems

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    For radiative direct exchange areas in three dimensional system,the Uniform Deterministic Discrete Method(UDDM) was adopted.The spherical surface dividing method for sending area element and the regular icosahedron for sending volume element can meet with the direct exchange area computation of any kind of zone pairs.The numerical examples of direct exchange area in three dimensional system with nonhomogeneous attenuation coefficients indicated that the UDDM can give very high numercal accuracy.

  2. Three-dimensional decomposition method of global atmospheric circulation

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    By adopting the idea of three-dimensional Walker, Hadley and Rossby stream functions, the global atmospheric circulation can be considered as the sum of three stream functions from a global per- spective. Therefore, a mathematical model of three-dimensional decomposition of global atmospheric circulation is proposed and the existence and uniqueness of the model are proved. Besides, the model includes a numerical method leading to no truncation error in the discrete three-dimensional grid points. Results also show that the three-dimensional stream functions exist and are unique for a given velocity field. The mathematical model shows the generalized form of three-dimensional stream func- tions equal to the velocity field in representing the features of atmospheric motion. Besides, the vertical velocity calculated through the model can represent the main characteristics of the vertical motion. In sum, the three-dimensional decomposition of atmospheric circulation is convenient for the further in- vestigation of the features of global atmospheric motions.

  3. Ordered three-dimensional interconnected nanoarchitectures in anodic porous alumina

    Science.gov (United States)

    Martín, Jaime; Martín-González, Marisol; Fernández, Jose Francisco; Caballero-Calero, Olga

    2014-01-01

    Three-dimensional nanostructures combine properties of nanoscale materials with the advantages of being macro-sized pieces when the time comes to manipulate, measure their properties, or make a device. However, the amount of compounds with the ability to self-organize in ordered three-dimensional nanostructures is limited. Therefore, template-based fabrication strategies become the key approach towards three-dimensional nanostructures. Here we report the simple fabrication of a template based on anodic aluminum oxide, having a well-defined, ordered, tunable, homogeneous 3D nanotubular network in the sub 100 nm range. The three-dimensional templates are then employed to achieve three-dimensional, ordered nanowire-networks in Bi2Te3 and polystyrene. Lastly, we demonstrate the photonic crystal behavior of both the template and the polystyrene three-dimensional nanostructure. Our approach may establish the foundations for future high-throughput, cheap, photonic materials and devices made of simple commodity plastics, metals, and semiconductors. PMID:25342247

  4. Method for aortic wall strain measurement with three-dimensional ultrasound speckle tracking and fitted finite element analysis.

    Science.gov (United States)

    Karatolios, Konstantinos; Wittek, Andreas; Nwe, Thet Htar; Bihari, Peter; Shelke, Amit; Josef, Dennis; Schmitz-Rixen, Thomas; Geks, Josef; Maisch, Bernhard; Blase, Christopher; Moosdorf, Rainer; Vogt, Sebastian

    2013-11-01

    Aortic wall strains are indicators of biomechanical changes of the aorta due to aging or progressing pathologies such as aortic aneurysm. We investigated the potential of time-resolved three-dimensional ultrasonography coupled with speckle-tracking algorithms and finite element analysis as a novel method for noninvasive in vivo assessment of aortic wall strain. Three-dimensional volume datasets of 6 subjects without cardiovascular risk factors and 2 abdominal aortic aneurysms were acquired with a commercial real time three-dimensional echocardiography system. Longitudinal and circumferential strains were computed offline with high spatial resolution using a customized commercial speckle-tracking software and finite element analysis. Indices for spatial heterogeneity and systolic dyssynchrony were determined for healthy abdominal aortas and abdominal aneurysms. All examined aortic wall segments exhibited considerable heterogenous in-plane strain distributions. Higher spatial resolution of strain imaging resulted in the detection of significantly higher local peak strains (p ≤ 0.01). In comparison with healthy abdominal aortas, aneurysms showed reduced mean strains and increased spatial heterogeneity and more pronounced temporal dyssynchrony as well as delayed systole. Three-dimensional ultrasound speckle tracking enables the analysis of spatially highly resolved strain fields of the aortic wall and offers the potential to detect local aortic wall motion deformations and abnormalities. These data allow the definition of new indices by which the different biomechanical properties of healthy aortas and aortic aneurysms can be characterized. Copyright © 2013 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  5. Preoperative diagnosis of the thoracic aortic aneurysm by three-dimensional CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Adachi, Hideo; Ino, Takashi; Ide, Hirofumi; Mizuhara, Akihiro; Yamaguchi, Atsushi; Kawahito, Koji; Kobayashi, Yasuyuki; Nagai, Jun (Jichi Medical School, Minamikawachi, Tochigi (Japan))

    1993-09-01

    Serial eight patients with thoracic aortic aneurysms were evaluated by a newly developed three-dimensional CT angiography (3D-CT) from December 1992 to January 1993. The patients include 3 aortic dissections, 3 aortic arch aneurysms, one descending aortic aneurysm and one thoraco-abdominal aortic aneurysm. The surgical treatment was performed after the evaluation of 3D-CT, and the operative findings were compared to the three-dimensional images reconstructed by 3D-CT in all patients. Three-dimensional displays were achieved using the unique method of data collection of the helical (spinal) scanner with continuous tube rotation and continuous table feed. An intravenous contrast material was used to image the thoracic aorta and major aortic branches with the single-breath-hold technique. Two and three-dimensional images reconstructed by 3D-CT were displayed within 10-20 minutes after the scanning. These three-dimensional images of the aortic lesions could be displayed in any angle we chose. Three-dimensional structures of the thoracic aorta and major aortic branches were clearly visualized and easily recognized by 3D-CT. These images were similar to the intraoperative findings and were quite useful to determine the operative procedure. The successful repair of thoracic aortic aneurysm was achieved in all cases. 3D-CT is a new and attractive modality to assess the vascular system. Although our experience is limited, 3D-CT may be a useful and powerful diagnostic method for the surgical treatment of thoracic aortic aneurysm. (author).

  6. Three-dimensional magnetospheric equilibrium with isotropic pressure

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, C.Z.

    1995-05-01

    In the absence of the toroidal flux, two coupled quasi two-dimensional elliptic equilibrium equations have been derived to describe self-consistent three-dimensional static magnetospheric equilibria with isotropic pressure in an optimal ({Psi},{alpha},{chi}) flux coordinate system, where {Psi} is the magnetic flux function, {chi} is a generalized poloidal angle, {alpha} is the toroidal angle, {alpha} = {phi} {minus} {delta}({Psi},{phi},{chi}) is the toroidal angle, {delta}({Psi},{phi},{chi}) is periodic in {phi}, and the magnetic field is represented as {rvec B} = {del}{Psi} {times} {del}{alpha}. A three-dimensional magnetospheric equilibrium code, the MAG-3D code, has been developed by employing an iterative metric method. The main difference between the three-dimensional and the two-dimensional axisymmetric solutions is that the field-aligned current and the toroidal magnetic field are finite for the three-dimensional case, but vanish for the two-dimensional axisymmetric case. With the same boundary flux surface shape, the two-dimensional axisymmetric results are similar to the three-dimensional magnetosphere at each local time cross section.

  7. Biodynamic profiling of three-dimensional tissue growth techniques

    Science.gov (United States)

    Sun, Hao; Merrill, Dan; Turek, John; Nolte, David

    2016-03-01

    Three-dimensional tissue culture presents a more biologically relevant environment in which to perform drug development than conventional two-dimensional cell culture. However, obtaining high-content information from inside three dimensional tissue has presented an obstacle to rapid adoption of 3D tissue culture for pharmaceutical applications. Biodynamic imaging is a high-content three-dimensional optical imaging technology based on low-coherence interferometry and digital holography that uses intracellular dynamics as high-content image contrast. In this paper, we use biodynamic imaging to compare pharmaceutical responses to Taxol of three-dimensional multicellular spheroids grown by three different growth techniques: rotating bioreactor, hanging-drop and plate-grown spheroids. The three growth techniques have systematic variations among tissue cohesiveness and intracellular activity and consequently display different pharmacodynamics under identical drug dose conditions. The in vitro tissue cultures are also compared to ex vivo living biopsies. These results demonstrate that three-dimensional tissue cultures are not equivalent, and that drug-response studies must take into account the growth method.

  8. Coupled particle dispersion by three-dimensional vortex structures

    Energy Technology Data Exchange (ETDEWEB)

    Troutt, T.R.; Chung, J.N.; Crowe, C.T.

    1996-12-31

    The primary objective of this research program is to obtain understanding concerning the role of three-dimensional vortex structures in the dispersion of particles and droplets in free shear flows. This research program builds on previous studies which focused on the nature of particle dispersion in large scale quasi two-dimensional vortex structures. This investigation employs time dependent experimental and numerical techniques to provide information concerning the particulate dispersion produced by three dimensional vortex structures in free shear layers. The free shear flows investigated include modified plane mixing layers, and modified plane wakes. The modifications to these flows involve slight perturbations to the initiation boundary conditions such that three-dimensional vortex structures are rapidly generated by the experimental and numerical flow fields. Recent results support the importance of these vortex structures in the particle dispersion process.

  9. Hydrofocusing Bioreactor for Three-Dimensional Cell Culture

    Science.gov (United States)

    Gonda, Steve R.; Spaulding, Glenn F.; Tsao, Yow-Min D.; Flechsig, Scott; Jones, Leslie; Soehnge, Holly

    2003-01-01

    The hydrodynamic focusing bioreactor (HFB) is a bioreactor system designed for three-dimensional cell culture and tissue-engineering investigations on orbiting spacecraft and in laboratories on Earth. The HFB offers a unique hydrofocusing capability that enables the creation of a low-shear culture environment simultaneously with the "herding" of suspended cells, tissue assemblies, and air bubbles. Under development for use in the Biotechnology Facility on the International Space Station, the HFB has successfully grown large three-dimensional, tissuelike assemblies from anchorage-dependent cells and grown suspension hybridoma cells to high densities. The HFB, based on the principle of hydrodynamic focusing, provides the capability to control the movement of air bubbles and removes them from the bioreactor without degrading the low-shear culture environment or the suspended three-dimensional tissue assemblies. The HFB also provides unparalleled control over the locations of cells and tissues within its bioreactor vessel during operation and sampling.

  10. Computational methods for three-dimensional microscopy reconstruction

    CERN Document Server

    Frank, Joachim

    2014-01-01

    Approaches to the recovery of three-dimensional information on a biological object, which are often formulated or implemented initially in an intuitive way, are concisely described here based on physical models of the object and the image-formation process. Both three-dimensional electron microscopy and X-ray tomography can be captured in the same mathematical framework, leading to closely-related computational approaches, but the methodologies differ in detail and hence pose different challenges. The editors of this volume, Gabor T. Herman and Joachim Frank, are experts in the respective methodologies and present research at the forefront of biological imaging and structural biology.   Computational Methods for Three-Dimensional Microscopy Reconstruction will serve as a useful resource for scholars interested in the development of computational methods for structural biology and cell biology, particularly in the area of 3D imaging and modeling.

  11. Radiation hardness of three-dimensional polycrystalline diamond detectors

    Energy Technology Data Exchange (ETDEWEB)

    Lagomarsino, Stefano, E-mail: lagomarsino@fi.infn.it; Sciortino, Silvio [National Institute of Nuclear Physics (INFN), Via B. Rossi, 1-3, 50019 Sesto Fiorentino (Italy); Department of Physics and Astronomy, University of Florence, Via G. Sansone 1, 50019 Sesto Fiorentino (Italy); Bellini, Marco [European Laboratory for Non-Linear Spectroscopy, Via Nello Carrara 1, 50019 Sesto Fiorentino (Italy); Istituto Nazionale di Ottica (INO-CNR), Largo Enrico Fermi 6, 50125 Firenze (Italy); Corsi, Chiara [Department of Physics and Astronomy, University of Florence, Via G. Sansone 1, 50019 Sesto Fiorentino (Italy); European Laboratory for Non-Linear Spectroscopy, Via Nello Carrara 1, 50019 Sesto Fiorentino (Italy); Cindro, Vladimir [Jozef Stefan Institute, Jamova cesta 39, 1000 Ljubljana (Slovenia); Kanxheri, Keida; Servoli, Leonello [National Institute of Nuclear Physics (INFN), Via A. Pascoli, 06123 Perugia (Italy); Department of Physics, University of Perugia, Via A. Pascoli, 06123 Perugia (Italy); Morozzi, Arianna [Department of Engineering, University of Perugia, Via G. Duranti 93, 06125 Perugia (Italy); Passeri, Daniele [National Institute of Nuclear Physics (INFN), Via A. Pascoli, 06123 Perugia (Italy); Department of Engineering, University of Perugia, Via G. Duranti 93, 06125 Perugia (Italy); Schmidt, Christian J. [GSI Helmholtzzentrum für Schwerionenforschung, Planckstraße 1, 64291 Darmstadt (Germany)

    2015-05-11

    The three-dimensional concept in particle detection is based on the fabrication of columnar electrodes perpendicular to the surface of a solid state radiation sensor. It permits to improve the radiation resistance characteristics of a material by lowering the necessary bias voltage and shortening the charge carrier path inside the material. If applied to a long-recognized exceptionally radiation-hard material like diamond, this concept promises to pave the way to the realization of detectors of unprecedented performances. We fabricated conventional and three-dimensional polycrystalline diamond detectors, and tested them before and after neutron damage up to 1.2 ×10{sup 16 }cm{sup −2}, 1 MeV-equivalent neutron fluence. We found that the signal collected by the three-dimensional detectors is up to three times higher than that of the conventional planar ones, at the highest neutron damage ever experimented.

  12. Three-dimensional network of Drosophila brain hemisphere

    CERN Document Server

    Mizutani, Ryuta; Takeuchi, Akihisa; Uesugi, Kentaro; Suzuki, Yoshio

    2016-01-01

    The first step to understanding brain function is to determine the brain's network structure. We report a three-dimensional analysis of the brain network of the fruit fly Drosophila melanogaster by synchrotron-radiation tomographic microscopy. A skeletonized wire model of the left half of the brain network was built by tracing the three-dimensional distribution of X-ray absorption coefficients. The obtained models of neuronal processes were classified into groups on the basis of their three-dimensional structures. These classified groups correspond to neuronal tracts that send long-range projections or repeated structures of the optic lobe. The skeletonized model is also composed of neuronal processes that could not be classified into the groups. The distribution of these unclassified structures correlates with the distribution of contacts between neuronal processes. This suggests that neurons that cannot be classified into typical structures should play important roles in brain functions. The quantitative de...

  13. Validating two-dimensional leadership models on three-dimensionally structured fish schools

    Science.gov (United States)

    Nagy, Máté; Holbrook, Robert I.; Biro, Dora; Burt de Perera, Theresa

    2017-01-01

    Identifying leader–follower interactions is crucial for understanding how a group decides where or when to move, and how this information is transferred between members. Although many animal groups have a three-dimensional structure, previous studies investigating leader–follower interactions have often ignored vertical information. This raises the question of whether commonly used two-dimensional leader–follower analyses can be used justifiably on groups that interact in three dimensions. To address this, we quantified the individual movements of banded tetra fish (Astyanax mexicanus) within shoals by computing the three-dimensional trajectories of all individuals using a stereo-camera technique. We used these data firstly to identify and compare leader–follower interactions in two and three dimensions, and secondly to analyse leadership with respect to an individual's spatial position in three dimensions. We show that for 95% of all pairwise interactions leadership identified through two-dimensional analysis matches that identified through three-dimensional analysis, and we reveal that fish attend to the same shoalmates for vertical information as they do for horizontal information. Our results therefore highlight that three-dimensional analyses are not always required to identify leader–follower relationships in species that move freely in three dimensions. We discuss our results in terms of the importance of taking species' sensory capacities into account when studying interaction networks within groups.

  14. Three-dimensional microtomographic imaging of human brain cortex

    CERN Document Server

    Mizutania, Ryuta; Uesugi, Kentaro; Ohyama, Masami; Takekoshi, Susumu; Osamura, R Yoshiyuki; Suzuki, Yoshio

    2016-01-01

    This paper describes an x-ray microtomographic technique for imaging the three-dimensional structure of the human cerebral cortex. Neurons in the brain constitute a neural circuit as a three-dimensional network. The brain tissue is composed of light elements that give little contrast in a hard x-ray transmission image. The contrast was enhanced by staining neural cells with metal compounds. The obtained structure revealed the microarchitecture of the gray and white matter regions of the frontal cortex, which is responsible for the higher brain functions.

  15. Three-dimensional flow and turbulence structure in electrostatic precipitator

    DEFF Research Database (Denmark)

    Ullum, Thorvald Uhrskov; Larsen, Poul Scheel; Özcan, Oktay

    2002-01-01

    Stereo PIV is employed to study the three-dimensional velocity and turbulence fields in a laboratory model of a negative corona, barbed-wire, smooth-plate, electrostatic precipitator (figure 1). The study is focused on determining the parametric effects of axial development, mean current density Jm...... and bulk velocity U0 on secondary flows and turbulence levels and structures due to the action of the three-dimensional electrostatic field on the charged gas. At constant bulk velocity (U0 = 1 m/s) and current density (Jm = 0.4 mA/m2), secondary flows in the form of rolls of axial vorticity with swirl...

  16. A class of auxetic three-dimensional lattices

    CERN Document Server

    Cabras, Luigi

    2015-01-01

    We propose a class of auxetic three-dimensional lattice structures. The elastic microstructure can be designed in order to have omni-directional Poisson's ratio arbitrarily close to the stability limit -1. The cubic behavior of the periodic system has been fully characterized; the minumum and maximum Poisson's ratio and the associated principal directions are given as a function of the microstructural parameters. The initial microstructure is then modified into a body centered-cubic system that can achieve a Poisson's ratio lower than -1 and that can also behave as an isotropic three-dimensional auxetic structure.

  17. Three dimensional super-resolution in metamaterial slab lenses

    CERN Document Server

    Mesa, F; Freire, M; Baena, J D

    2005-01-01

    This letter presents a theoretical and experimental study on the viability of obtaining three dimensional super-resolution (i.e. resolution overcoming the diffraction limit for all directions in space) by means of metamaterial slab lenses. Although the source field cannot be actually reproduced at the back side of the lens with super-resolution in all space directions, the matching capabilities of metamaterial slabs does make it possible the detection of images with three-dimensional super-resolution. This imaging takes place because of the coupling between the evanescent space harmonic components of the field generated at both the source and the detector.

  18. A system of three-dimensional complex variables

    Science.gov (United States)

    Martin, E. Dale

    1986-01-01

    Some results of a new theory of multidimensional complex variables are reported, including analytic functions of a three-dimensional (3-D) complex variable. Three-dimensional complex numbers are defined, including vector properties and rules of multiplication. The necessary conditions for a function of a 3-D variable to be analytic are given and shown to be analogous to the 2-D Cauchy-Riemann equations. A simple example also demonstrates the analogy between the newly defined 3-D complex velocity and 3-D complex potential and the corresponding ordinary complex velocity and complex potential in two dimensions.

  19. Structure of turbulence in three-dimensional boundary layers

    Science.gov (United States)

    Subramanian, Chelakara S.

    1993-01-01

    This report provides an overview of the three dimensional turbulent boundary layer concepts and of the currently available experimental information for their turbulence modeling. It is found that more reliable turbulence data, especially of the Reynolds stress transport terms, is needed to improve the existing modeling capabilities. An experiment is proposed to study the three dimensional boundary layer formed by a 'sink flow' in a fully developed two dimensional turbulent boundary layer. Also, the mean and turbulence field measurement procedure using a three component laser Doppler velocimeter is described.

  20. Urologic applications of multiplanar and three-dimensional computed tomography.

    Science.gov (United States)

    Olson, M C; Posniak, H V

    1995-01-01

    The introduction of helical computed tomography (CT) has resulted in improved quality of multiplanar reformations and three-dimensional reconstructions in the chest and abdomen and has made CT angiography a clinical reality. These imaging techniques are useful for evaluating the urinary tract, adding a new dimension to its display, resulting in improved diagnosis of renal and perirenal disease. This article reviews the indications and techniques utilized for multiplanar and three-dimensional CT for urology. The advantages and limitations are discussed, and normal and pathologic findings in the urinary tract illustrated.

  1. Gas-Kinetic BGK Scheme for Three Dimensional Magnetohydrodynamics

    Institute of Scientific and Technical Information of China (English)

    Huazhong

    2010-01-01

    The gas-kinetic theory based flux splitting method has been successfully proposed for solving one- and two-dimensional ideal magnetohydrodynamics by Xu et al.[J. Comput. Phys., 1999; 2000], respectively. This paper extends the kinetic method to solve three-dimensional ideal magnetohydrodynamics equations, where an adaptive parameter η is used to control the numerical dissipation in the flux splitting method.Several numerical examples are given to demonstrate that the proposed method can achieve high numerical accuracy and resolve strong discontinuous waves in three dimensional ideal MHD problems.

  2. Three Dimensional Imaging with Multiple Wavelength Speckle Interferometry

    Energy Technology Data Exchange (ETDEWEB)

    Bernacki, Bruce E.; Cannon, Bret D.; Schiffern, John T.; Mendoza, Albert

    2014-05-28

    We present the design, modeling, construction, and results of a three-dimensional imager based upon multiple-wavelength speckle interferometry. A surface under test is illuminated with tunable laser light in a Michelson interferometer configuration while a speckled image is acquired at each laser frequency step. The resulting hypercube is Fourier transformed in the frequency dimension and the beat frequencies that result map the relative offsets of surface features. Synthetic wavelengths resulting from the laser tuning can probe features ranging from 18 microns to hundreds of millimeters. Three dimensional images will be presented along with modeling results.

  3. Fabrication and characterization of three-dimensional biomimetic chiral composites.

    Science.gov (United States)

    Turner, Mark D; Schröder-Turk, Gerd E; Gu, Min

    2011-05-09

    Here we show the fabrication and characterization of a novel class of biomimetic photonic chiral composites inspired by a recent finding in butterfly wing-scales. These three-dimensional networks have cubic symmetry, are fully interconnected, have robust mechanical strength and possess chirality which can be controlled through the composition of multiple chiral networks, providing an excellent platform for developing novel chiral materials. Using direct laser writing we have fabricated different types of chiral composites that can be engineered to form novel photonic devices. We experimentally show strong circular dichroism and compare with numerical simulations to illustrate the high quality of these three-dimensional photonic structures.

  4. Symmetries and defects in three-dimensional topological field theory

    CERN Document Server

    Fuchs, Jurgen

    2015-01-01

    Boundary conditions and defects of any codimension are natural parts of any quantum field theory. Surface defects in three-dimensional topological field theories of Turaev-Reshetikhin type have applications to two-dimensional conformal field theories, in solid state physics and in quantum computing. We explain an obstruction to the existence of surface defects that takes values in a Witt group. We then turn to surface defects in Dijkgraaf-Witten theories and their construction in terms of relative bundles; this allows one to exhibit Brauer-Picard groups as symmetry groups of three-dimensional topological field theories.

  5. Data Visualization in Physics II: VRML and Java for three-dimensional imaging and fully three-dimensional movies

    Science.gov (United States)

    Fenton, Flavio H.; Evans, Steven J.; Hastings, Harold M.; Cherry, Elizabeth M.

    2006-03-01

    Presentation and analysis of large three-dimensional data sets is in general hard to do using only two-dimensional figures and plots. In this talk, we will demonstrate techniques for illustrating static and dynamic three-dimensional objects and data using Virtual Reality Modeling Language (VRML) as well as Java. The advantage of these two languages is that they are platform-independent, which allows for easy sharing of data and visualizations. In addition, manipulation of data is relatively easy as rotation, translation and zooming can be done in real- time for static objects as well as for data and objects that vary and deform in time. Examples of fully three-dimensional movies will be shown, including dendritic growth and propagation of electrical waves in cardiac tissue. In addition, we will show how to include VRML and Java viewers in PowerPoint for easy presentation of results in classes and seminars.

  6. Approaching the Sequential and Three-Dimensional Organization of Genomes

    NARCIS (Netherlands)

    T.A. Knoch (Tobias)

    2006-01-01

    textabstractGenomes are one of the major foundations of life due to their role in information storage, process regulation and evolution. To achieve a deeper unterstanding of the human genome the three-dimensional organization of the human cell nucleus, the structural-, scaling- and dynamic prope

  7. Vacuum polarization around a three-dimensional black hole

    CERN Document Server

    Shiraishi, Kiyoshi

    2015-01-01

    We calculate the Euclidean propagator for a conformally coupled massless scalar field in the background of the three-dimensional black hole. The expectation value $\\langle\\varphi^2\\rangle$ in the Hartle-Hawking state is obtained in the spacetime.

  8. Generation of a Desired Three-Dimensional Electromagnetic Field

    DEFF Research Database (Denmark)

    2005-01-01

    The present invention relates to a method and a system for synthesizing a prescribed three-dimensional electromagnetic field based on generalized phase contrast imaging. Such a method and apparatus may be utilized in advanced optical micro and nano-manipulation, such as by provision of a multiple...

  9. Three-dimensional reconstruction of the otosclerotic focus

    DEFF Research Database (Denmark)

    Bloch, Sune Land; Sørensen, Mads Sølvsten

    2010-01-01

    The location and three-dimensional (3D) shapes of the otosclerotic foci suggest a general centripetal distribution of otosclerotic bone remodeling around the inner ear space, whereas the normal bone remodeling is distributed centrifugally. The existence of an inverse spatial relation between normal...

  10. Computer Generated Holography as a Three-Dimensional Display Medium

    Science.gov (United States)

    1990-12-01

    series of two dimensional images are reflected on an object screen resulting in an autostereoscopic , or true three dimensional, images. The advantages of...an attractive target to optimize. Jack Ritter has suggested a fast approximation to 3D Euclidean distance calculations (10:432). His methid uses no

  11. Resistive drift wave turbulence in a three-dimensional geometry

    DEFF Research Database (Denmark)

    Korsholm, Søren Bang; Michelsen, Poul; Naulin, V.

    1999-01-01

    The Hasegawa-Wakatani model describing resistive drift waves is investigated analytically and numerically in a three-dimensional periodic geometry. After an initial growth of the energy the drift waves couple nonlinearly to convective cells, which eventually dominate the system completely...

  12. Three-Dimensional Evolution of the Galactic Fountain

    CERN Document Server

    D'Avillez, M A

    1999-01-01

    Gas that escapes from the Galactic disk, rises into the halo, cools and falls back, constitutes a "Galactic Fountain". Three-Dimensional simulations show that such a fountain model reproduces many of the features that have been observed in the Galaxy and other galaxies such as M31 and M33. Here, these results are reported.

  13. Three-Dimensional Bone Adaptation of the Proximal Femur

    DEFF Research Database (Denmark)

    Bagge, Mette

    1998-01-01

    The bone remodeling of a three-dimensional model of the proximal femur is considered. The bone adaptation is numerically described as an evolution in time formulated such that the structural change goes in an optimal direction within each time step for the optimal boundary conditions. In the bone...

  14. THE THREE DIMENSIONAL MODELS AND THEIR IDENTIFICATION MINING SUBSIDENCE

    Institute of Scientific and Technical Information of China (English)

    WUGe; SHENGuanghan; JIXiaoming; WANGQuanke

    1995-01-01

    The theory and method for selecting the three dimensional prediction models of mining subsidence are studied in this paper. Namely, based on system identification and statistics theory, an optimum mining subsidence prediction model can be selected. The method proved by a typical case has a good prospect for determining the physical model of rock mass for mining subsidence prediction.

  15. BIFURCATION OF PERIODIC ORBITS OF A THREE-DIMENSIONAL SYSTEM

    Institute of Scientific and Technical Information of China (English)

    LIU XUANLIANG; HAN MAOAN

    2005-01-01

    Consider a three-dimensional system having an invariant surface. By using bifurcation techniques and analyzing the solutions of bifurcation equations, the authors study the spacial bifurcation phenomena of a k multiple closed orbit in the invariant surface.The sufficient conditions of the existence of many closed orbits bifurcate from the k multiple closed orbit are obtained.

  16. Three dimensional geometric modeling of processing-tomatoes

    Science.gov (United States)

    Characterizing tomato geometries with different shapes and sizes would facilitate the design of tomato processing equipments and promote computer-based engineering simulations. This research sought to develop a three-dimensional geometric model that can describe the morphological attributes of proce...

  17. Thermodynamics of a Simple Three-Dimensional DNA Hairpin Model

    CERN Document Server

    Kremer, Kellan; Boggess, Erin; Mask, Walker; Saucedo, Tony; Hansen, JJ; Appelgate, Ian; Jurgensen, Taylor; Santos, Aaron

    2016-01-01

    We characterize the equation of state for a simple three-dimensional DNA hairpin model using a Metropolis Monte Carlo algorithm. This algorithm was run at constant temperature and fixed separation between the terminal ends of the strand. From the equation of state, we compute the compressibility, thermal expansion coefficient, and specific heat along with adiabatic path.

  18. Three-dimensional simulations of viscoelastic instability in polymeric filaments

    DEFF Research Database (Denmark)

    Rasmussen, Henrik Koblitz; Hassager, Ole

    1999-01-01

    The three-dimensional Langrangian integral method is used to simulate the elastic end-plate instability that occurs in the rapid extension of some polymeric filaments between parallel plates. It is demonstrated that the upper convected Maxwell model describes the essential features of the instabi...

  19. Two-Dimensional Chirality in Three-Dimensional Chemistry.

    Science.gov (United States)

    Wintner, Claude E.

    1983-01-01

    The concept of two-dimensional chirality is used to enhance students' understanding of three-dimensional stereochemistry. This chirality is used as a key to teaching/understanding such concepts as enaniotropism, diastereotopism, pseudoasymmetry, retention/inversion of configuration, and stereochemical results of addition to double bonds. (JN)

  20. A Three-Dimensional Haptic Matrix Test of Nonverbal Reasoning

    Science.gov (United States)

    Miller, Joseph C.; Skillman, Gemma D.; Benedetto, Joanne M.; Holtz, Ann M.; Nassif, Carrie L.; Weber, Anh D.

    2007-01-01

    Three-dimensional haptic matrices were pilot-tested as a nonvisual measure of cognitive ability. The results indicated that they correlated with convergent measures, with emphasis on spatial processing and that the participants who described items "visually" completed them more quickly and accurately and tended to have become visually impaired…

  1. Polycrystalline diamond detectors with three-dimensional electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Lagomarsino, S., E-mail: lagomarsino@fi.infn.it [University of Florence, Department of Physics, Via Sansone 1, 50019 Sesto Fiorentino (Italy); INFN Firenze, Via B. Rossi 1, 50019 Sesto Fiorentino (Italy); Bellini, M. [INO-CNR Firenze, Largo E. Fermi 6, 50125 Firenze (Italy); Brianzi, M. [INFN Firenze, Via B. Rossi 1, 50019 Sesto Fiorentino (Italy); Carzino, R. [Smart Materials-Nanophysics, Istituto Italiano di Tecnologia, Genova, Via Morego 30, 16163 Genova (Italy); Cindro, V. [Joseph Stefan Institute, Jamova Cesta 39, 1000 Ljubljana (Slovenia); Corsi, C. [University of Florence, Department of Physics, Via Sansone 1, 50019 Sesto Fiorentino (Italy); LENS Firenze, Via N. Carrara 1, 50019 Sesto Fiorentino (Italy); Morozzi, A.; Passeri, D. [INFN Perugia, Perugia (Italy); Università degli Studi di Perugia, Dipartimento di Ingegneria, via G. Duranti 93, 06125 Perugia (Italy); Sciortino, S. [University of Florence, Department of Physics, Via Sansone 1, 50019 Sesto Fiorentino (Italy); INFN Firenze, Via B. Rossi 1, 50019 Sesto Fiorentino (Italy); Servoli, L. [INFN Perugia, Perugia (Italy)

    2015-10-01

    The three-dimensional concept in diamond detectors has been applied, so far, to high quality single-crystal material, in order to test this technology in the best available conditions. However, its application to polycrystalline chemical vapor deposited diamond could be desirable for two reasons: first, the short inter-electrode distance of three-dimensional detectors should improve the intrinsically lower collection efficiency of polycrystalline diamond, and second, at high levels of radiation damage the performances of the poly-crystal material are not expected to be much lower than those of the single crystal one. We report on the fabrication and test of three-dimensional polycrystalline diamond detectors with several inter-electrode distances, and we demonstrate that their collection efficiency is equal or higher than that obtained with conventional planar detectors fabricated with the same material. - Highlights: • Pulsed laser fabrication of polycristalline diamond detectors with 3D electrodes. • Measurement of the charge collection efficiency (CCE) under beta irradiation. • Comparation between the CCE of 3D and conventional planar diamond sensors. • A rationale for the behavior of three-dimensional and planar sensors is given.

  2. Potential Flows From Three-Dimensional Complex Variables

    Science.gov (United States)

    Martin, E. Dale; Kelly, Patrick H.; Panton, Ronald L.

    1992-01-01

    Report presents investigation of several functions of three-dimensional complex variable, with emphasis on potential-flow fields computed from these functions. Part of continuing research on generalization of well-established two-dimensional complex analysis to three and more dimensions.

  3. Three-dimensional modes of a symmetric nonlinear plane waveguide

    Science.gov (United States)

    Akhmediev, N. N.; Nabiev, R. F.; Popov, Yu. M.

    1989-01-01

    The three-dimensional problem of a symmetric nonlinear plane waveguide, which consist of a linear medium layer surrounded by nonlinear media, is investigated. The stationary solution of this problem is a mode whose field is falling to zero at infinity in all directions perpendicular to the propagation direction. The even, odd and assymetrical solutions of the problem are obtained.

  4. Oblique water entry of a three dimensional body

    Directory of Open Access Journals (Sweden)

    Scolan Yves-Marie

    2014-12-01

    Full Text Available The problem of the oblique water entry of a three dimensional body is considered. Wagner theory is the theoretical framework. Applications are discussed for an elliptic paraboloid entering an initially flat free surface. A dedicated experimental campaign yields a data base for comparisons. In the present analysis, pressure, force and dynamics of the wetted surface expansion are assessed.

  5. Three-Dimensional Reconstruction of Macroscopic Features in Biological Materials

    Science.gov (United States)

    Krumnikl, Michal; Sojka, Eduard; Gaura, Jan; Motyka, Oldřich

    This paper covers the topic of three dimensional reconstruction of small textureless formations usually found in biological samples. Generally used reconstructing algorithms do not provide sufficient accuracy for surface analysis. In order to achieve better results, combined strategy was developed, linking stereo matching algorithms with monocular depth cues such as depth from focus and depth from illumination.

  6. Three-dimensional stiffness of the carpal arch.

    Science.gov (United States)

    Gabra, Joseph N; Li, Zong-Ming

    2016-01-01

    The carpal arch of the wrist is formed by irregularly shaped carpal bones interconnected by numerous ligaments, resulting in complex structural mechanics. The purpose of this study was to determine the three-dimensional stiffness characteristics of the carpal arch using displacement perturbations. It was hypothesized that the carpal arch would exhibit an anisotropic stiffness behavior with principal directions that are oblique to the conventional anatomical axes. Eight (n=8) cadavers were used in this study. For each specimen, the hamate was fixed to a custom stationary apparatus. An instrumented robot arm applied three-dimensional displacement perturbations to the ridge of trapezium and corresponding reaction forces were collected. The displacement-force data were used to determine a three-dimensional stiffness matrix using least squares fitting. Eigendecomposition of the stiffness matrix was used to identify the magnitudes and directions of the principal stiffness components. The carpal arch structure exhibited anisotropic stiffness behaviors with a maximum principal stiffness of 16.4±4.6N/mm that was significantly larger than the other principal components of 3.1±0.9 and 2.6±0.5N/mm (pcarpal tunnel which is accounted for by the stiff transverse ligaments that tightly bind distal carpal arch. The minimal principal stiffness is attributed to the less constraining articulation between the trapezium and scaphoid. This study provides advanced characterization of the wrist׳s three-dimensional structural stiffness for improved insight into wrist biomechanics, stability, and function.

  7. Three-Dimensional Space to Assess Cloud Interoperability

    Science.gov (United States)

    2013-03-01

    major cloud providers, OpenStack and OpeNebula, to demonstrate the usage of the three-dimensional space and its benefits . We start this chapter with a...documentation:rel4.0:external_auth. [68] X. Gao, P. Shah, A. Yoga , A. Kodgire and X. Ni. Cloud storage survey [Online]. Available: http

  8. Three-dimensional charge transport in organic semiconductor single crystals.

    Science.gov (United States)

    He, Tao; Zhang, Xiying; Jia, Jiong; Li, Yexin; Tao, Xutang

    2012-04-24

    Three-dimensional charge transport anisotropy in organic semiconductor single crystals - both plates and rods (above and below, respectively, in the figure) - is measured in well-performing organic field-effect transistors for the first time. The results provide an excellent model for molecular design and device preparation that leads to good performance.

  9. Differential equations of the shell suspension. Three-dimensional problem

    OpenAIRE

    Гнатейко, Нонна Валентинівна

    2016-01-01

    Differential equations of suspension of gyroscope are constructed as a shell of rotation. Analytical material well-being of analysis of properties of suspension as a system with part parameters is created. Three-dimensional approach gives possibility for the comprehensive study of errors of devices of inertial navigation from position impedance status.

  10. Polyimide Aerogels with Three-Dimensional Cross-Linked Structure

    Science.gov (United States)

    Meador, Mary Ann B. (Inventor)

    2016-01-01

    A method for creating a three dimensional cross-linked polyimide structure includes dissolving a diamine, a dianhydride, and a triamine in a solvent, imidizing a polyamic acid gel by heating the gel, extracting the gel in a second solvent, supercritically drying the gel, and removing the solvent to create a polyimide aerogel.

  11. Three-dimensional reconstruction of the pigeon inner ear

    NARCIS (Netherlands)

    Hofman, R.; Segenhout, J. M.; Wit, H. P.

    2009-01-01

    Three-dimensional reconstructions of the inner ear of the pigeon (Columba livia domestica), from two-dimensional images, obtained with (conventional) light microscopy or orthogonal-plane fluorescence optical sectioning (OPFOS), are presented. The results are compared with available information on th

  12. Renormalization group theory of the three dimensional dilute Bose gas

    NARCIS (Netherlands)

    Bijlsma, M.; Stoof, H.T.C.

    1996-01-01

    We study the three-dimensional atomic Bose gas using renormalization group techniques. Using our knowledge of the microscopic details of the interatomic interaction, we determine the correct initial values of our renormalization group equations and thus obtain also information on nonuniversal

  13. Algebraic Ricci Solitons of three-dimensional Lorentzian Lie groups

    CERN Document Server

    Batat, Wafaa

    2011-01-01

    We classify Algebraic Ricci Solitons of three-dimensional Lorentzian Lie groups. All algebraic Ricci solitons that we obtain are sol-solitons. In particular, we prove that, contrary to the Riemannian case, Lorentzian Ricci solitons need not to be algebraic Ricci solitons.

  14. Three-Dimensional Printing Using a Photoinitiated Polymer

    Science.gov (United States)

    Muskin, Joseph; Ragusa, Matthew; Gelsthorpe, Thomas

    2010-01-01

    Printers capable of producing three-dimensional objects are becoming more common. Most of these printers are impractical for use in the chemistry classroom because of the expense incurred in fabricating a print head that must be controlled in three dimensions. We propose a simpler solution to this problem that allows the emerging technology of…

  15. Three dimensional boundary layers on submarine conning towers and rudders

    Science.gov (United States)

    Gleyzes, C.

    1988-01-01

    Solutions for the definition of grids adapted to the calculation of three-dimensional boundary layers on submarine conning towers and on submarine rudders and fins are described. The particular geometry of such bodies (oblique shaped hull, curved fins) required special adaptations. The grids were verified on examples from a test basin.

  16. Three-Dimensional Printing Using a Photoinitiated Polymer

    Science.gov (United States)

    Muskin, Joseph; Ragusa, Matthew; Gelsthorpe, Thomas

    2010-01-01

    Printers capable of producing three-dimensional objects are becoming more common. Most of these printers are impractical for use in the chemistry classroom because of the expense incurred in fabricating a print head that must be controlled in three dimensions. We propose a simpler solution to this problem that allows the emerging technology of…

  17. Three-dimensional topology optimized electrically-small conformal antenna

    DEFF Research Database (Denmark)

    Erentok, Aycan; Sigmund, Ole

    2008-01-01

    A three-dimensional (3D) conductor-based conformal electrically small antenna is obtained using a topology optimization method. The optimization method distributes a certain amount of conductive material to a designated design domain such that the material layout defines an electrically small...

  18. Optimal eavesdropping in cryptography with three-dimensional quantum states.

    Science.gov (United States)

    Bruss, D; Macchiavello, C

    2002-03-25

    We study optimal eavesdropping in quantum cryptography with three-dimensional systems, and show that this scheme is more secure against symmetric attacks than protocols using two-dimensional states. We generalize the according eavesdropping transformation to arbitrary dimensions, and discuss the connection with optimal quantum cloning.

  19. A Novel Three-Dimensional Tool for Teaching Human Neuroanatomy

    Science.gov (United States)

    Estevez, Maureen E.; Lindgren, Kristen A.; Bergethon, Peter R.

    2010-01-01

    Three-dimensional (3D) visualization of neuroanatomy can be challenging for medical students. This knowledge is essential in order for students to correlate cross-sectional neuroanatomy and whole brain specimens within neuroscience curricula and to interpret clinical and radiological information as clinicians or researchers. This study implemented…

  20. Three-dimensional reconstruction of the otosclerotic focus

    DEFF Research Database (Denmark)

    Bloch, Sune Land; Sørensen, Mads Sølvsten

    2010-01-01

    The location and three-dimensional (3D) shapes of the otosclerotic foci suggest a general centripetal distribution of otosclerotic bone remodeling around the inner ear space, whereas the normal bone remodeling is distributed centrifugally. The existence of an inverse spatial relation between normal...

  1. Scattering and conductance quantization in three-dimensional metal nanocontacts

    DEFF Research Database (Denmark)

    Brandbyge, Mads; Jacobsen, Karsten Wedel; Nørskov, Jens Kehlet

    1997-01-01

    The transmission through three-dimensional nanocontacts is calculated in the presence of localized scattering centers and boundary scattering using a coupled-channel recursion method. Simple confining potentials are used to investigate how robust the observation of quantized conductance is with r...

  2. Three-Dimensional Extension of a Digital Library Service System

    Science.gov (United States)

    Xiao, Long

    2010-01-01

    Purpose: The paper aims to provide an overall methodology and case study for the innovation and extension of a digital library, especially the service system. Design/methodology/approach: Based on the three-dimensional structure theory of the information service industry, this paper combines a comprehensive analysis with the practical experiences…

  3. Exploring Approaches to Teaching in Three-Dimensional Virtual Worlds

    Science.gov (United States)

    Englund, Claire

    2017-01-01

    Purpose: The purpose of this paper is to explore how teachers' approaches to teaching and conceptions of teaching and learning with educational technology influence the implementation of three-dimensional virtual worlds (3DVWs) in health care education. Design/methodology/approach: Data were collected through thematic interviews with eight…

  4. Three dimensional rigorous model for optical scattering problems

    NARCIS (Netherlands)

    Wei, X.

    2006-01-01

    We present a three-dimensional model based on the finite element method for solving the time-harmonic Maxwell equation in optics. It applies to isotropic or anisotropic dielectrics and metals, and to many configurations such as an isolated scatterer in a multilayer, bi-gratings and crystals. We shal

  5. Combine use of two and three dimensional transesophageal echocardiography in rheumatic mitral valve repair%经食管二维与实时三维超声结合在风湿性二尖瓣病变成形术中的应用

    Institute of Scientific and Technical Information of China (English)

    马宁; 李治安; 杨娅

    2011-01-01

    Objective: To investigate the use of transcsophagcal cchocardiography (TEE) in rheumatic mitral valve repair. Method:TEE was performed in 26 patients with rheumatic mitral valve disease before mitral valve repair. The length, thickness of mitral leaf, dimension of mitral valve annulusand and the type of mitral valve dysfunction were evaluated by 2D-TEE. The location of disease was analyzed by 3D-TEE. Result; Ten patients (38. 5%) with isolated serious mitral valve rcgurgitation, 4 patients (15. 4%) with isolated serious mitral stenosis, 3 patients (11. 5%) with serious mitral valve rcgurgitation combined mordcratc stenosis, 9 patients (34. 6%) with serious mitral valve rcgurgitation combined mild stenosis were diagnosed by TEE. Mitral valve dysfunction type fJ 4 pets (15. 4%), fJ Affla-P 18 pets (69. 2%) , I a-AI a-P 4 pets (15. 4%). After mitral valve repair immediately, TEE evaluated 3 cases with valve repair were failed, 2 of them were performed valve replacement. Con-clusion:TEE could evaluate the function of mitral valve dysfunction, measure the length thickness of mitral leaf and the dimension of mitral valve annulus, provid adequate valuable information before and after rheumatic mitral valve repair. TEE docs play an important role in rheumatic mitral valve repair.%目的:研究经食管二维与实时三维超声结合在风湿性二尖瓣病变成形术中的作用.方法:26例临床诊断为风湿性二尖瓣病变拟行二尖瓣成形术患者,术前联合应用经食管二维超声与实时三维超声,对二尖瓣功能不全进行分类,详细定位病变部位,测量二尖瓣前后叶厚度、长度及瓣环径.术后即刻评价疗效.结果:术前超声诊断单纯风湿性二尖瓣关闭不全10例(38.5%),单纯二尖瓣狭窄4例(15.4%),二尖瓣关闭不全重度伴狭窄轻度9例(34.6%),二尖瓣关闭不全重度伴狭窄中度3例(11.5%);瓣膜功能不全Ⅱ型4例(15.4%),ⅡAⅢa-P型18例(69.2%),Ⅲa-AⅢa-P型4例(15.4%).术后即刻超声评价疗效,3例在超声指导下2次成形,其中2例最终选择瓣膜置换术.结论:经食管二维和实时三维超声心动图结合,在风湿性二尖瓣病变成形术前对瓣膜功能不全进行分类诊断,能准确评估二尖瓣叶厚度和长度,指导术式和人工瓣环的选择.术后即刻评价疗效,在风湿性二尖瓣成形术中有重要的应用价值.

  6. One-, Two-, and Three-Dimensional Heterospin Complexes Consisting of 4-(N-tert-Butyloxylamino)pyridine (4NOpy), Dicyanamide Ion (DCA), and 3d Metal Ions: Crystal Structures and Magnetic Properties of [M(II)(4NOpy)x(DCA)y(CH3CN)z]n (M = Mn, Co, Ni, Cu, Zn).

    Science.gov (United States)

    Ogawa, Hiraku; Mori, Koya; Murashima, Kensuke; Karasawa, Satoru; Koga, Noboru

    2016-01-19

    Solutions of 3d metal ion salts, M(NO3)2, 4-(N-tert-butyloxylamino)pyridine (4NOpy), and dicyanamide (DCA) in CH3CN were mixed to afford single crystals of the polymeric complexes [M(II)(4NOpy)x(DCA)y(CH3CN)z]n (M(II) = Mn (1), Co (2), Ni (3), Cu (4a and 4b), Zn (5)). X-ray crystallography revealed that the crystal structures are a three-dimensional (3-D) network for 1, 2-D networks for 2, 3, 4a, and 5, and a 1-D chain for 4b. Crystals of 2, 3, 4a, and 5 contained CH3CN molecules as crystal solvents, which were readily desorbed in the ambient atmosphere. After desorption of the CH3CN molecules, the crystal structures of 2 and 3 were confirmed to be slightly shrunk without destruction of the crystal lattice. Crystals of 2, 3, 4a, and 5 after desorption of crystal solvents were used for investigations of the magnetic properties. Complex 1 showed antiferromagnetic interactions to form a ferrimagnetic chain and exhibited the magnetic behavior of a 2-D (or 3-D) spin-canted antiferromagnet with TN = 12 K. Complex 2 containing anisotropic Co(II) ions also showed the behavior of a 1-D (or 2-D) spin-canted antiferromagnet with TN = 6 K. In 3, 4a, and 4b, the aminoxyl of 4NOpy ferromagnetically interacted with the metal ion with coupling constants of JM-NO/kB = 45, 45, and 43 K, respectively. In 5, the magnetic couplings between the aminoxyls in 4NOpy through the diamagnetic Zn(II) ion were weakly antiferromagntic (JNO-NO = -1.2 K). DCA might be a weak antiferromagnetic connector for the metal chains.

  7. A computer code for three-dimensional incompressible flows using nonorthogonal body-fitted coordinate systems

    Science.gov (United States)

    Chen, Y. S.

    1986-03-01

    In this report, a numerical method for solving the equations of motion of three-dimensional incompressible flows in nonorthogonal body-fitted coordinate (BFC) systems has been developed. The equations of motion are transformed to a generalized curvilinear coordinate system from which the transformed equations are discretized using finite difference approximations in the transformed domain. The hybrid scheme is used to approximate the convection terms in the governing equations. Solutions of the finite difference equations are obtained iteratively by using a pressure-velocity correction algorithm (SIMPLE-C). Numerical examples of two- and three-dimensional, laminar and turbulent flow problems are employed to evaluate the accuracy and efficiency of the present computer code. The user's guide and computer program listing of the present code are also included.

  8. Three-Dimensional Waves in Tilt Thermal Boundary Layers

    Institute of Scientific and Technical Information of China (English)

    TAO Jian-Jun; YUAN Xiang-Jiang

    2009-01-01

    We numerically and theoretically study the stabilities of tilt thermal boundary layers immersed in stratified air. An interesting phenomenon is revealed: the stationary longitudinal-roll mode becomes unstable to some oscillating state even when the Grashof number is smaller than its corresponding critical value. By stability analysis, this phenomenon is explained in terms of a new three-dimensional wave mode. The effect of the tilt angle on the stability of the boundary flows is investigated. Since the new three-dimensional wave is found to be the most unstable mode when the title angle is between 30° and 64°, it is expected to play an important role in the transition to turbulence.

  9. Three-dimensional P velocity structure in Beijing area

    Institute of Scientific and Technical Information of China (English)

    于湘伟; 陈运泰; 王培德

    2003-01-01

    A detail three-dimensional P wave velocity structure of Beijing, Tianjin and Tangshan area (BTT area) was determined by inverting local earthquake data. In total 16 048 P wave first arrival times from 16048 shallow and mid-depth crustal earthquakes, which occurred in and around the BTT area from 1992 to 1999 were used. The first arrival times are recorded by Northern China United Telemetry Seismic Network and Yanqing-Huailai Digital Seismic Network. Hypocentral parameters of 1 132 earthquakes with magnitude ML=1.7~6.2 and the three-dimensional P wave velocity structure were obtained simultaneously. The inversion result reveals the complicated lateral heterogeneity of P wave velocity structure around BTT area. The tomographic images obtained are also found to explain other seismological observations well.

  10. Three-dimensional radiation transfer modeling in a dicotyledon leaf

    Science.gov (United States)

    Govaerts, Yves M.; Jacquemoud, Stéphane; Verstraete, Michel M.; Ustin, Susan L.

    1996-11-01

    The propagation of light in a typical dicotyledon leaf is investigated with a new Monte Carlo ray-tracing model. The three-dimensional internal cellular structure of the various leaf tissues, including the epidermis, the palisade parenchyma, and the spongy mesophyll, is explicitly described. Cells of different tissues are assigned appropriate morphologies and contain realistic amounts of water and chlorophyll. Each cell constituent is characterized by an index of refraction and an absorption coefficient. The objective of this study is to investigate how the internal three-dimensional structure of the tissues and the optical properties of cell constituents control the reflectance and transmittance of the leaf. Model results compare favorably with laboratory observations. The influence of the roughness of the epidermis on the reflection and absorption of light is investigated, and simulation results confirm that convex cells in the epidermis focus light on the palisade parenchyma and increase the absorption of radiation.

  11. Three Dimensional Energy Transmitting Boundary in the Time Domain

    Directory of Open Access Journals (Sweden)

    Naohiro eNakamura

    2015-11-01

    Full Text Available Although the energy transmitting boundary is accurate and efficient for the FEM earthquake response analysis, it could be applied in the frequency domain only. In the previous papers, the author proposed an earthquake response analysis method using the time domain energy transmitting boundary for two dimensional problems. In this paper, this technique is expanded for three dimensional problems. The inner field is supposed to be a hexahedron shape and the approximate time domain boundary is explained, first. Next, two dimensional anti-plane time domain boundary is studied for a part of the approximate three dimensional boundary method. Then, accuracy and efficiency of the proposed method are confirmed by example problems.

  12. Three-Dimensional Structure of Solar Wind Turbulence

    CERN Document Server

    Chen, C H K; Schekochihin, A A; Horbury, T S; Wicks, R T; Bale, S D

    2011-01-01

    We have measured, for the first time, the three-dimensional structure of inertial range plasma turbulence in the fast solar wind with respect to a local, physically motivated coordinate system. We found that the incompressible Alfvenic fluctuations are three-dimensionally anisotropic, with the sense of this anisotropy changing from large to small scales. At the largest scales, the magnetic field correlations are longest in the local fluctuation direction, consistent with Alfven waves. At the smallest scales, they are longest along the local mean field direction and shortest in the direction perpendicular to the local mean field and the local field fluctuation. The compressive fluctuations are highly elongated along the local mean magnetic field direction, although axially symmetric perpendicular to it. Their large anisotropy may explain why they are not heavily damped.

  13. Three-dimensional mapping of single-atom magnetic anisotropy.

    Science.gov (United States)

    Yan, Shichao; Choi, Deung-Jang; Burgess, Jacob A J; Rolf-Pissarczyk, Steffen; Loth, Sebastian

    2015-03-11

    Magnetic anisotropy plays a key role in the magnetic stability and spin-related quantum phenomena of surface adatoms. It manifests as angular variations of the atom's magnetic properties. We measure the spin excitations of individual Fe atoms on a copper nitride surface with inelastic electron tunneling spectroscopy. Using a three-axis vector magnet we rotate the magnetic field and map out the resulting variations of the spin excitations. We quantitatively determine the three-dimensional distribution of the magnetic anisotropy of single Fe atoms by fitting the spin excitation spectra with a spin Hamiltonian. This experiment demonstrates the feasibility of fully mapping the vector magnetic properties of individual spins and characterizing complex three-dimensional magnetic systems.

  14. Atomic force microscope study of three-dimensional nanostructure sidewalls

    Energy Technology Data Exchange (ETDEWEB)

    Hussain, Muhammad Mustafa [SEMATECH, 2706 Montopolis Drive, Austin, TX 78741 (United States); Gondran, Carolyn F H [Advanced Technology Development Facility, 2706 Montopolis Drive, Austin, TX 78741 (United States); Michelson, Diane K [International SEMATECH Manufacturing Initiative, 2706 Montopolis Drive, Austin, TX 78741 (United States)

    2007-08-22

    Next generation planar and non-planar complementary metal oxide semiconductor (CMOS) structures are three-dimensional nanostructures with multi-layer stacks that can contain films thinner than ten atomic layers. The high resolution of transmission electron microscopy (TEM) is typically chosen for studying properties of these stacks such as film thickness, interface and interfacial roughness. However, TEM sample preparation is time-consuming and destructive, and TEM analysis is expensive and can provide problematic results for surface and interface roughness. Therefore, in this paper, we present the use of direct measurements of sidewall surface structures by conventional atomic force microscopy (AFM) as an alternative or complementary method for studying multi-layer film stacks and as the preferred method for studying FinFET sidewall surface roughness. In addition to these semiconductor device applications, this AFM sidewall measurement technique could be used for other three-dimensional nanostructures.

  15. Three-dimensional hybrid networks based on aspartic acid

    Indian Academy of Sciences (India)

    Anupama Ghosh; R A Sanguramath

    2008-01-01

    Three-dimensional achiral coordination polymers of the general formula M2(D, L-NHCH (COO)CH2COO)2.C4H4N2 where M = Ni and Co and pyrazine acts as the linker molecule have been prepared under hydrothermal conditions starting with [M(L-NHCH(COO)CH2COO).3H2O] possessing a helical chain structure. A three-dimensional hybrid compound of the formula Pb2.5[N{CH(COO)CH2COO}22H2O] has also been prepared hydrothermally starting with aspartic acid and Pb(NO3)2. In this lead compound, where a secondary amine formed by the dimerisation of aspartic acid acts as the ligand, there is two-dimensional inorganic connectivity and one-dimensional organic connectivity.

  16. Artificial three-dimensional niches deconstruct pancreas development in vitro.

    Science.gov (United States)

    Greggio, Chiara; De Franceschi, Filippo; Figueiredo-Larsen, Manuel; Gobaa, Samy; Ranga, Adrian; Semb, Henrik; Lutolf, Matthias; Grapin-Botton, Anne

    2013-11-01

    In the context of a cellular therapy for diabetes, methods for pancreatic progenitor expansion and subsequent differentiation into insulin-producing beta cells would be extremely valuable. Here we establish three-dimensional culture conditions in Matrigel that enable the efficient expansion of dissociated mouse embryonic pancreatic progenitors. By manipulating the medium composition we generate either hollow spheres, which are mainly composed of pancreatic progenitors, or complex organoids that spontaneously undergo pancreatic morphogenesis and differentiation. The in vitro maintenance and expansion of pancreatic progenitors require active Notch and FGF signaling, thus recapitulating in vivo niche signaling interactions. Our experiments reveal new aspects of pancreas development, such as a community effect by which small groups of cells better maintain progenitor properties and expand more efficiently than isolated cells, as well as the requirement for three-dimensionality. Finally, growth conditions in chemically defined biomaterials pave the way for testing the biophysical and biochemical properties of the niche that sustains pancreatic progenitors.

  17. Time multiplexed pinhole array based lensless three-dimensional imager

    Science.gov (United States)

    Schwarz, Ariel; Wang, Jingang; Shemer, Amir; Zalevsky, Zeev; Javidi, Bahram

    2016-06-01

    We present an overview of multi variable coded aperture (MVCA) for lensless three-dimensional integral imaging (3D II) systems. The new configuration is based on a time multiplexing method using a variable pinholes array design. The system provides higher resolution 3D images with improved light intensity and signal to noise ratio as compared to single pinhole system. The MVCA 3D II system configuration can be designed to achieve high light intensity for practical use as micro lenslets arrays. This new configuration preserves the advantages of pinhole optics while solving the resolution limitation problem and the long exposure time of such systems. The three dimensional images are obtained with improved resolution, signal to noise ratio and sensitivity efficiency. This integral imaging lensless system is characterized by large depth of focus, simplicity and low cost. In this paper we present numerical simulations as well as experimental results that validate the proposed lensless imaging configuration.

  18. Electroencephalographic (EEG) control of three-dimensional movement

    Science.gov (United States)

    McFarland, Dennis J.; Sarnacki, William A.; Wolpaw, Jonathan R.

    2010-06-01

    Brain-computer interfaces (BCIs) can use brain signals from the scalp (EEG), the cortical surface (ECoG), or within the cortex to restore movement control to people who are paralyzed. Like muscle-based skills, BCIs' use requires activity-dependent adaptations in the brain that maintain stable relationships between the person's intent and the signals that convey it. This study shows that humans can learn over a series of training sessions to use EEG for three-dimensional control. The responsible EEG features are focused topographically on the scalp and spectrally in specific frequency bands. People acquire simultaneous control of three independent signals (one for each dimension) and reach targets in a virtual three-dimensional space. Such BCI control in humans has not been reported previously. The results suggest that with further development noninvasive EEG-based BCIs might control the complex movements of robotic arms or neuroprostheses.

  19. Three-Dimensional All-Dielectric Photonic Topological Insulator

    CERN Document Server

    Slobozhanyuk, Alexey; Ni, Xiang; Smirnova, Daria; Kivshar, Yuri S; Khanikaev, Alexander B

    2016-01-01

    The discovery of two-dimensional topological photonic systems has transformed our views on electromagnetic propagation and scattering of classical waves, and a quest for similar states in three dimensions, known to exist in condensed matter systems, has been put forward. Here we demonstrate that symmetry protected three-dimensional topological states can be engineered in an all-dielectric platform with the electromagnetic duality between electric and magnetic fields ensured by the structure design. Magneto-electric coupling playing the role of a synthetic gauge field leads to a topological transition to an insulating regime with a complete three-dimensional photonic bandgap. An emergence of surface states with conical Dirac dispersion and spin-locking is unimpeded. Robust propagation of surface states along two-dimensional domain walls defined by the reversal of magneto-electric coupling is confirmed numerically by first principle studies. It is shown that the proposed system represents a table-top platform f...

  20. Moyamoya disease: diagnosis with three-dimensional CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Tsuchiya, K. (Dept. of Radiology, National Defense Medical Coll., Saitama (Japan) Dept. of Radiology, Kyorin Univ. School of Medicine, Tokyo (Japan)); Makita, K. (Dept. of Radiology, National Defense Medical Coll., Saitama (Japan) Dept. of Radiology, Social Health Insurance Medical Center, Tokyo (Japan)); Furui, S. (Dept. of Radiology, National Defense Medical Coll., Saitama (Japan) Dept. of Diagnostic Radiology, Toranomon Kyosai Hospital, Tokyo (Japan))

    1994-08-01

    Our purpose was to assess the value of three-dimensional (3D) CT angiography in the diagnosis of moyamoya disease. We studied seven patients with moyamoya disease proved by conventional angiography. Three-dimensional (3D) CT angiography was performed using rapid sequence or helical (spiral) scanning in conjunction with a bolus injection of intravenous contrast medium. All seven patients could be diagnosed as having moyamoya disease on the basis of the following 3D CT angiographic findings: poor visualisation of the main trunks and/or major branches of anterior and middle cerebral arteries (7 patients); dilated leptomeningeal anastomotic channels from the posterior cerebral arteries (4); and demonstration of ''moyamoya vessels'' in the basal ganglia (2). Although conventional angiography remains the principal imaging technique for demonstrating anatomical changes in detail, less invasive 3D CT angiography provides a solid means of diagnosing moyamoya disease when it is suspected on CT, MRI, or clinical grounds. (orig.)

  1. Three-Dimensional Modeling of Guide-Field Magnetic Reconnection

    Science.gov (United States)

    Hesse, Michael

    2005-01-01

    The dissipation mechanism of guide field magnetic reconnection remains a subject of intense scientific interest. On one hand, one set of recent studies have shown that particle inertia-based processes, which include thermal and bulk inertial effects, provide the reconnection electric field in the diffusion region. On the other hand, a second set of studies emphasizes the role of wave-particle interactions in providing anomalous resistivity in the diffusion region. In this presentation, we analyze three-dimensional PIC simulations of guide-field magnetic reconnection. Specific emphasis will be on the question whether thermal-inertia processes, mediated by the electron pressure tensor, remain a viable dissipation mechanism in fully three-dimensional systems.

  2. Slightly Two or Three Dimensional Self-Similar Solutions

    CERN Document Server

    Sari, Re'em; Yalinewich, Almog; MacFadyen, Andrew

    2011-01-01

    Self similarity allows for analytic or semi-analytic solutions to many hydrodynamics problems. Most of these solutions are one dimensional. Using linear perturbation theory, expanded around such a one-dimensional solution, we find self-similar hydrodynamic solutions that are two- or three-dimensional. Since the deviation from a one-dimensional solution is small, we call these slightly two-dimensional and slightly three-dimensional self-similar solutions, respectively. As an example, we treat strong spherical explosions of the second type. A strong explosion propagates into an ideal gas with negligible temperature and density profile of the form rho(r,theta,phi)=r^{-omega}[1+sigma*F(theta,phi)], where omega>3 and sigma << 1. Analytical solutions are obtained by expanding the arbitrary function F(theta,phi) in spherical harmonics. We compare our results with two dimensional numerical simulations, and find good agreement.

  3. Three-Dimensional Dynamical Instabilities in Galactic Ionization Fronts

    CERN Document Server

    Whalen, D J; Whalen, Daniel J.; Norman, Michael L.

    2007-01-01

    Ionization front instabilities have long been of interest for their suspected role in a variety of phenomena in the galaxy, from the formation of bright rims and 'elephant trunks' in nebulae to triggered star formation in molecular clouds. Numerical treatments of these instabilities have historically been limited in both dimensionality and input physics, leaving important questions about their true evolution unanswered. We present the first three-dimensional radiation hydrodynamical calculations of both R-type and D-type ionization front instabilities in galactic environments (i.e., solar metallicity gas). Consistent with linear stability analyses of planar D-type fronts, our models exhibit many short-wavelength perturbations growing at early times that later evolve into fewer large-wavelength structures. The simulations demonstrate that both self-consistent radiative transfer and three-dimensional flow introduce significant morphological differences to unstable modes when compared to earlier two-dimensional ...

  4. Stability analysis of cracks propagating in three dimensional solids

    Energy Technology Data Exchange (ETDEWEB)

    Larralde, H.; Al-Falou, A.A.; Ball, R.C. [Cavendish Lab., Cambridge (United Kingdom)

    1996-12-01

    The authors present a theory for the morphology of the fracture surface left behind by slowly propagating cracks in linear, isotropic and homogeneous three dimensional solids. The results are based on first order perturbation theory of the equations of elasticity for cracks whose shape is slightly perturbed from planar. For cracks propagating under pure type 1 loading they find that all perturbation modes are linearly stable, from which they can predict the roughness of the fracture surface induced by fluctuations in the material. The authors compare their results with the classical results for cracks propagating in two dimensional systems, and discuss the effects in the three dimensional analysis which result from taking into account contributions from non-singular terms of the stress field, as well as the effects arising from finite speeds of crack propagation.

  5. Magnetic field intensification by three-dimensional explosion process

    CERN Document Server

    Hotta, H; Yokoyama, T

    2012-01-01

    We investigate an intensification mechanism for the magnetic field near the base of the solar convection zone that does not rely on differential rotation. Such mechanism in addition to differential rotation has been suggested by studies of flux emergence, which typically require field strength in excess of those provided by differential rotation alone. We study here a process in which potential energy of the superadiabatically stratified convection zone is converted into magnetic energy. This mechanism, know as explosion of magnetic flux tubes, has been previously studied in the thin flux tube approximation as well as two-dimensional MHD simulations, we expand the investigation to three-dimensional MHD simulations. Our main result is that enough intensification can be achieved in a three-dimensional magnetic flux sheet as long as the spatial scale of the imposed perturbation normal to the magnetic field is sufficiently large. When this spatial scale is small, the flux sheet tends to rise toward the surface, r...

  6. Canonical and symplectic analysis for three dimensional gravity without dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Escalante, Alberto, E-mail: aescalan@ifuap.buap.mx [Instituto de Física, Benemérita Universidad Autónoma de Puebla, Apartado Postal J-48 72570, Puebla, Pue. (Mexico); Osmart Ochoa-Gutiérrez, H. [Facultad de Ciencias Físico Matemáticas, Benemérita Universidad Autónoma de Puebla, Apartado postal 1152, 72001 Puebla, Pue. (Mexico)

    2017-03-15

    In this paper a detailed Hamiltonian analysis of three-dimensional gravity without dynamics proposed by V. Hussain is performed. We report the complete structure of the constraints and the Dirac brackets are explicitly computed. In addition, the Faddeev–Jackiw symplectic approach is developed; we report the complete set of Faddeev–Jackiw constraints and the generalized brackets, then we show that the Dirac and the generalized Faddeev–Jackiw brackets coincide to each other. Finally, the similarities and advantages between Faddeev–Jackiw and Dirac’s formalism are briefly discussed. - Highlights: • We report the symplectic analysis for three dimensional gravity without dynamics. • We report the Faddeev–Jackiw constraints. • A pure Dirac’s analysis is performed. • The complete structure of Dirac’s constraints is reported. • We show that symplectic and Dirac’s brackets coincide to each other.

  7. Three-dimensional theory for light-matter interaction

    DEFF Research Database (Denmark)

    Sørensen, Martin Westring; Sørensen, Anders Søndberg

    2008-01-01

    We present a full quantum mechanical three dimensional theory describing an electromagnetic field interacting with an ensemble of identical atoms. The theory is constructed such that it describes recent experiments on light-matter quantum interfaces, where the quantum fluctuations of light...... to a dressed state picture, where the light modes are solutions to the diffraction problem, and develop a perturbative expansion in the fluctuations. The fluctuations are due to quantum fluctuations as well as the random positions of the atoms. In this perturbative expansion we show how the quantum...... fluctuations are mapped between atoms and light while the random positioning of the atoms give rise to decay due to spontaneous emission. Furthermore we identify limits, where the full three dimensional theory reduce to the one dimensional theory typically used to describe the interaction....

  8. Three Dimensional Iterative Reconstruction Techniques in Positron Tomography.

    Science.gov (United States)

    Sloka, Scott

    The acquisition of positron tomographic data in three dimensions is an improvement over the two dimensional acquisition of data because the greater the number of measurements taken of a stochastic process, the more accurately determined the desired parameter may be. This research pursues the goal of three dimensional image reconstruction in Positron Tomography using an iterative approach. This thesis has followed a systematic approach to the exploration of a system for three dimensional iterative reconstruction. System design parameters were discussed such as the advantages and disadvantages of iterative vs analytic methods, the implementation of two, three dimensional iterative algorithms, the selection of a ray passing method, and the choice of an analytic method for comparison to the iterative methods. Several qualitative and quantitative tests were used/developed and performed to analyse and compare the results. Three dimensional reconstruction in Positron Tomography using two iterative techniques (ART and ML-EM) was demonstrated. The ML-EM algorithm was adapted to satisfy the objective of equalizing the estimates with the measurements via division of the sampling density. A new multi-objective function methodology was developed for two dimensions and its extension to three dimensions discussed. A smoothly-varying Gaussian phantom was created for comparing artifacts from different ray passing methods. The analysis of voxel trends over many iterations was used. The use of the output from a two dimensional filtered backprojection algorithm as the seed for three dimensional algorithms to accelerate the reconstruction the was explored. The importance of the selection of a good ray ordering in ART and its effects on the total squared error were explored. For the phantoms studied in this thesis, the ML -EM algorithm tended to perform better under most conditions. This algorithm is slower than ART to achieve both a low total squared error and good contrast, but the

  9. Influence of stable stratification on three-dimensional isotropic turbulence

    Science.gov (United States)

    Metais, O.

    The influence of a stable stratification on three-dimensional homogeneous turbulence is investigated by performing large eddy simulations with the subgrid scales procedure developed by Chollet and Lesieur for isotropic turbulence. Computational initial conditions close to those of the experiments performed by Itsweire, Helland and Van Atta allow the comparison of the experimental and numerical evolutions of density-stratified turbulent flows. Theoretical works by Riley, Metcalfe and Weisman and by Lilly suggest that low Froude number stably-stratified turbulence may be a nearly noninteracting superposition of wave and quasi-horizontal turbulent vortex motions. For our computations the stably-stratified turbulence seems to be a decaying three-dimensional turbulence pulsed by internal gravity waves. However some tendencies towards two-dimensional turbulence are observed.

  10. Three-dimensional metamaterials fabricated using Proton Beam Writing

    Energy Technology Data Exchange (ETDEWEB)

    Bettiol, A.A., E-mail: a.bettiol@nus.edu.sg [Centre for Ion Beam Applications, Department of Physics, National University of Singapore, 2 Science Dr. 3, Singapore 117542 (Singapore); Turaga, S.P.; Yan, Y.; Vanga, S.K. [Centre for Ion Beam Applications, Department of Physics, National University of Singapore, 2 Science Dr. 3, Singapore 117542 (Singapore); Chiam, S.Y. [NUS High School for Maths and Science, 20 Clementi Avenue 1, Singapore 129957 (Singapore)

    2013-07-01

    Proton Beam Writing (PBW) is a direct write lithographic technique that has recently been applied to the fabrication of three dimensional metamaterials. In this work, we show that the unique capabilities of PBW, namely the ability to fabricate arrays of high resolution, high aspect ratio microstructures in polymer or replicated into metal, is well suited to metamaterials research. We have also developed a novel method for selectively electroless plating silver directly onto polymer structures that were fabricated using PBW. This method opens up new avenues for utilizing PBW for making metamaterials and other sub-wavelength metallic structures. Several potential applications of three dimensional metamaterials fabricated using PBW are discussed, including sensing and negative refractive index materials.

  11. Single florescent nanodiamond in a three dimensional ABEL trap

    Science.gov (United States)

    Kayci, Metin; Radenovic, Aleksandra

    2015-11-01

    Three dimensional single particle trapping and manipulation is an outstanding challenge in various fields ranging from basic physics to life sciences. By monitoring the response of a trapped particle to a designed environment one can extract its characteristics. In addition, quantum dynamics of a spatially scanned well-known particle can provide environmental information. Precise tracking and positioning of such a particle in aqueous environment is crucial task for achieving nano-scale resolution. Here we experimentally demonstrate three dimensional ABEL trap operating at high frequency by employing a hybrid approach in particle tracking. The particle location in the transverse plane is detected via a scanning laser beam while the axial position is determined by defocused imaging. The scanning of the trapped particle is accomplished through a nano positioning stage integrated to the trap platform.

  12. Three dimensional calculation of flux of low energy atmospheric neutrinos

    Science.gov (United States)

    Lee, H.; Bludman, S. A.

    1985-01-01

    Results of three-dimensional Monte Carlo calculation of low energy flux of atmospheric neutrinos are presented and compared with earlier one-dimensional calculations 1,2 valid at higher neutrino energies. These low energy neutrinos are the atmospheric background in searching for neutrinos from astrophysical sources. Primary cosmic rays produce the neutrino flux peaking at near E sub=40 MeV and neutrino intensity peaking near E sub v=100 MeV. Because such neutrinos typically deviate by 20 approximately 30 from the primary cosmic ray direction, three-dimensional effects are important for the search of atmospheric neutrinos. Nevertheless, the background of these atmospheric neutrinos is negligible for the detection of solar and supernova neutrinos.

  13. Three Dimensional Numerical Relativity with a Hyperbolic Formulation

    CERN Document Server

    Bona, C; Seidel, E; Walker, P; Bona, Carles; Masso, Joan; Seidel, Edward; Walker, Paul

    1998-01-01

    We discuss a successful three-dimensional cartesian implementation of the Bona-Massó hyperbolic formulation of the 3+1 Einstein evolution equations in numerical relativity. The numerical code, which we call ``Cactus,'' provides a general framework for 3D numerical relativity, and can include various formulations of the evolution equations, initial data sets, and analysis modules. We show important code tests, including dynamically sliced flat space, wave spacetimes, and black hole spacetimes. We discuss the numerical convergence of each spacetime, and also compare results with previously tested codes based on other formalisms, including the traditional ADM formalism. This is the first time that a hyperbolic reformulation of Einstein's equations has been shown appropriate for three-dimensional numerical relativity in a wide variety of spacetimes.

  14. Three-dimensional natural convection in a narrow spherical shell

    Science.gov (United States)

    Liu, Ming; Egbers, Christoph

    The convective motions in a shallow fluid layer between two concentric spheres in the presence of a constant axial force field have been studied numerically. The aspect ratio of the fluid layer to inner radius is beta =0.08, the Prandtl number Pra =37.5. A three-dimensional time-dependent numerical code is used to solve the governing equations in primitive variables. Convection in the sphe rical shell has then a highly three-dimensional nature. Characteristic flow patterns with a large number of banana-type cells, oriented in north-south direction and aligned in the azimuthal direction, are formed on the northern hemisphere, which grow gradually into the equatorial region accompanied by the generation of new cells as the Rayleigh number is increased. Various characteristics of these flows as well as their transient evolution are investigated for Rayleigh numbers up to 20 000.

  15. Three-Dimensional Reconstruction of Erythrocyte in the Capillary

    CERN Document Server

    Fan, Yifang; Li, Zhiyu; Lin, Wentao; Wei, Yuan; Zhong, Xing; Newman, Tony; Lv, Changsheng; Fan, Yuzhou

    2013-01-01

    The dynamic analysis of erythrocyte deformability is used as an important means for early diagnosis of blood diseases and blood rheology. Yet no effective method is available in terms of three-dimensional reconstruction of erythrocytes in a capillary. In this study, ultrathin serial sections of skeletal muscle tissue are obtained from the ultramicrotome, the tomographic images of an erythrocyte in a capillary are captured by the transmission electron microscope, and then a method to position and restore is devised to demonstrate the physiological relationship between two adjacent tomographic images of an erythrocyte. Both the modeling and the physical verification reveal that this method is effective, which means that it can be used to make three-dimensional reconstruction of an erythrocyte in a capillary. An example of reconstructed deformation of erythrocyte based on the serial ultrathin sections is shown at the end of this paper.

  16. Three-dimensional potential energy surface of Ar–CO

    Energy Technology Data Exchange (ETDEWEB)

    Sumiyoshi, Yoshihiro, E-mail: y-sumiyoshi@gunma-u.ac.jp [Division of Pure and Applied Science, Graduate School of Science and Technology, Gunma University, 4-2 Aramaki, Maebashi, Gunma 371-8510 (Japan); Endo, Yasuki [Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902 (Japan)

    2015-01-14

    A three-dimensional intermolecular potential energy surface of the Ar–CO complex has been determined by fitting most of the previously reported spectroscopic data, where observed transition frequencies by microwave, millimeter-wave, submillimeter-wave, and infrared spectroscopy were reproduced simultaneously within their experimental accuracies. A free rotor model Hamiltonian considering all the freedom of motions for an atom-diatom system was applied to calculate vibration-rotation energies. A three-dimensional potential energy surface obtained by ab initio calculations at the CCSD(T)-F12b/aug-cc-pV5Z level of theory was parameterized by a model function consisting of 46 parameters. They were used as initial values for the least-squares analysis of the experimental data. A total of 20 parameters were optimized to reproduce all the spectroscopic data.

  17. Relaxation techniques for three-dimensional transonic flow about wings.

    Science.gov (United States)

    Bailey, F. R.; Steger, J. L.

    1972-01-01

    A relaxation procedure has been developed to treat the three-dimensional, transonic small perturbation equations about finite lifting wings. A combination of two schemes is employed. For flow forward of the wing trailing edge the equations are written in terms of a velocity potential in order to minimize computer algebra and storage. For the remaining flow field the equations are written in terms of the velocity components in order to simplify the enforcement of the Kutta condition. Difference equations and relaxation procedures are described for both schemes. The computational method automatically captures the imbedded shock wave in the three-dimensional flow field. Computed results are given and compared to experiment and other inviscid methods.

  18. All-optical three-dimensional electron pulse compression

    CERN Document Server

    Wong, Liang Jie; Rohwer, Timm; Gedik, Nuh; Johnson, Steven G

    2014-01-01

    We propose an all-optical, three-dimensional electron pulse compression scheme in which Hermite-Gaussian optical modes are used to fashion a three-dimensional optical trap in the electron pulse's rest frame. We show that the correct choices of optical incidence angles are necessary for optimal compression. We obtain analytical expressions for the net impulse imparted by Hermite-Gaussian free-space modes of arbitrary order. Although we focus on electrons, our theory applies to any charged particle and any particle with non-zero polarizability in the Rayleigh regime. We verify our theory numerically using exact solutions to Maxwell's equations for first-order Hermite-Gaussian beams, demonstrating single-electron pulse compression factors of $>10^{2}$ in both longitudinal and transverse dimensions with experimentally realizable optical pulses. The proposed scheme is useful in ultrafast electron imaging for both single- and multi-electron pulse compression, and as a means of circumventing temporal distortions in ...

  19. Absence of bilinear condensate in three-dimensional QED

    CERN Document Server

    Karthik, Nikhil

    2016-01-01

    There are plausibility arguments that QED in three dimensions has a critical number of flavors of massless two-component fermions, below which scale invariance is broken by the presence of bilinear condensate. We present numerical evidences from our lattice simulations using dynamical overlap as well as Wilson-Dirac fermions for the absence of bilinear condensate for any even number of flavors of two-component fermions. Instead, we find evidences for the scale-invariant nature of three-dimensional QED.

  20. Three-dimensional magnetic reconnection through a moving magnetic null

    OpenAIRE

    Lukin, V. S.; Linton, M. G.

    2011-01-01

    A computational study of three-dimensional magnetic reconnection between two flux ropes through a moving reconnection site is presented. The configuration is considered in the context of two interacting spheromaks constrained by a perfectly conducting cylindrical boundary and oriented to form a single magnetic field null at its center. The initial magnetic field configuration is embedded into a uniform thermal plasma and is unstable to tilting. As the sphe...

  1. Three-dimensional magnetic reconnection through a moving magnetic null

    OpenAIRE

    Lukin, V. S.; Linton, M. G.

    2011-01-01

    A computational study of three-dimensional magnetic reconnection between two flux ropes through a moving reconnection site is presented. The configuration is considered in the context of two interacting spheromaks constrained by a perfectly conducting cylindrical boundary and oriented to form a single magnetic field null at its center. The initial magnetic field configuration is embedded into a uniform thermal plasma and is unstable to tilting. As the spheromaks tilt, their magnetic fi...

  2. Universally applicable three-dimensional hydrodynamic microfluidic flow focusing

    OpenAIRE

    Chiu, Yu-Jui; Cho, Sung Hwan; Mei, Zhe; Lien, Victor; Wu, Tsung-Feng; Lo, Yu-Hwa

    2013-01-01

    We have demonstrated a microfluidic device that can not only achieve three-dimensional flow focusing but also confine particles to the center stream along the channel. The device has a sample channel of smaller height and two sheath flow channels of greater height, merged into the downstream main channel where 3D focusing effects occur. We have demonstrated that both beads and cells in our device display significantly lower CVs in velocity and position distributions as well as reduced probabi...

  3. APPLICATIONS OF FRACTIONAL EXTERIOR DIFFERENTIAL IN THREE-DIMENSIONAL SPACE

    Institute of Scientific and Technical Information of China (English)

    陈勇; 闫振亚; 张鸿庆

    2003-01-01

    A brief survey of fractional calculus and fractional differential forms was firstly given. The fractional exterior transition to curvilinear coordinate at the origin were discussed and the two coordinate transformations for the fractional differentials for three-dimensional Cartesian coordinates to spherical and cylindrical coordinates are obtained, respectively. In particular, for v = m = 1 , the usual exterior transformations, between the spherical coordinate and Cartesian coordinate, as well as the cylindrical coordinate and Cartesian coordinate, are found respectively, from fractional exterior transformation.

  4. MRFD Method for Scattering From Three Dimensional Dielectric Bodies

    Directory of Open Access Journals (Sweden)

    A. F. Yagli

    2011-09-01

    Full Text Available A three-dimensional multiresolution frequency domain (MRFD method is established to compute bistatic radar cross sections of arbitrarily shaped dielectric objects. The proposed formulation is successfully verified by computing the bistatic radar cross sections of a dielectric sphere and a dielectric cube. Comparing the results to those obtained from the finite difference frequency domain (FDFD method simulations and analytic calculations, we demonstrated the computational time and memory advantages of MRFD method.

  5. Three-dimensional conceptual model for service-oriented simulation

    Institute of Scientific and Technical Information of China (English)

    Wen-guang WANG; Wei-ping WANG; Justyna ZANDER; Yi-fan ZHU

    2009-01-01

    In this letter, we propose a novel three-dimensional conceptual model for an emerging service-oriented simulation paradigm. The model can be used as a guideline or an analytic means to find the potential and possible future directions of the current simulation frameworks, In particular, the model inspects the crossover between the disciplines of modeling and simulation,service-orientation, and software/systems engineering. Finally, two specific simulation frameworks are studied as examples.

  6. Three-dimensional vortex structures under breaking waves

    OpenAIRE

    WATANABE Yasunori; Saeki, Hiroshi; Hosking, Roger J.

    2005-01-01

    The large-scale vortex structures under spilling and plunging breakers are investigated, using a fully three-dimensional large-eddy simulation (LES). When an overturning jet projecting from the crest in a breaking wave rebounds from the water surface ahead, the vorticity becomes unstable in a saddle region of strain between the rebounding jet and a primary spanwise vortex, resulting in spanwise undulations of the vorticity. The undulations are amplified on a braid in this saddle region, leadi...

  7. Probability current tornado loops in three-dimensional scattering

    CERN Document Server

    Exner, P; Exner, Pavel; Seba, Petr

    1998-01-01

    We consider scattering of a three-dimensional particle on a finite family of delta potentials. For some parameter values the scattering wavenctions exhibit nodal lines in the form of closed loops, which may touch but do not entangle. The corresponding probability current forms vortical singularities around these lines; if the scattered particle is charged, this gives rise to magnetic flux loops. The conclusions extend to scattering on hard obstacles or smooth potentials.

  8. Three-dimensional, computer simulated navigation in endoscopic neurosurgery

    Directory of Open Access Journals (Sweden)

    Roberta K. Sefcik, BHA

    2017-06-01

    Conclusion: Three-dimensional, frameless neuronavigation systems are useful in endoscopic neurosurgery to assist in the pre-operative planning of potential trajectories and to help localize the pathology of interest. Neuronavigation appears to be accurate to <1–2 mm without issues related to brain shift. Further work is necessary in the investigation of the effect of neuronavigation on operative time, cost, and patient-centered outcomes.

  9. Environmental, Transient, Three-Dimensional, Hydrothermal, Mass Transport Code - FLESCOT

    Energy Technology Data Exchange (ETDEWEB)

    Onishi, Yasuo [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bao, Jie [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Glass, Kevin A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Eyler, L. L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Okumura, Masahiko [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-03-28

    The purpose of the project was to modify and apply the transient, three-dimensional FLESCOT code to be able to effectively simulate cesium behavior in Fukushima lakes/dam reservoirs, river mouths, and coastal areas. The ultimate objective of the FLESCOT simulation is to predict future changes of cesium accumulation in Fukushima area reservoirs and costal water. These evaluation results will assist ongoing and future environmental remediation activities and policies in a systematic and comprehensive manner.

  10. Complete wetting in the three-dimensional transverse Ising model

    OpenAIRE

    Harris, A B; Micheletti, C.; Yeomans, J. M.

    1996-01-01

    We consider a three-dimensional Ising model in a transverse magnetic field, $h$ and a bulk field $H$. An interface is introduced by an appropriate choice of boundary conditions. At the point $(H=0,h=0)$ spin configurations corresponding to different positions of the interface are degenerate. By studying the phase diagram near this multiphase point using quantum-mechanical perturbation theory we show that that quantum fluctuations, controlled by $h$, split the multiphase degeneracy giving rise...

  11. A new three-dimensional general-relativistic hydrodynamics code

    Science.gov (United States)

    Baiotti, L.; Hawke, I.; Montero, P. J.; Rezzolla, L.

    We present a new three-dimensional general relativistic hydrodynamics code, the Whisky code. This code incorporates the expertise developed over the past years in the numerical solution of Einstein equations and of the hydrodynamics equations in a curved spacetime, and is the result of a collaboration of several European Institutes. We here discuss the ability of the code to carry out long-term accurate evolutions of the linear and nonlinear dynamics of isolated relativistic stars.

  12. A new three-dimensional general-relativistic hydrodynamics code

    CERN Document Server

    Baiotti, Luca; Montero, Pedro J; Rezzolla, Luciano

    2010-01-01

    We present a new three-dimensional general relativistic hydrodynamics code, the Whisky code. This code incorporates the expertise developed over the past years in the numerical solution of Einstein equations and of the hydrodynamics equations in a curved spacetime, and is the result of a collaboration of several European Institutes. We here discuss the ability of the code to carry out long-term accurate evolutions of the linear and nonlinear dynamics of isolated relativistic stars.

  13. Reentrance and ultrametricity in three-dimensional Ising spin glasses

    Science.gov (United States)

    Katzgraber, Helmut G.; Thomas, Creighton K.; Hartmann, Alexander K.

    2012-02-01

    We study the three-dimensional Edwards-Anderson Ising spin glass with bimodal disorder with a fraction of 22.8% antiferromagnetic bonds. Parallel tempering Monte Carlo simulations down to very low temperatures show that for this fraction of antiferromagnetic bonds the phase diagram of the system is reentrant, in agreement with previous results. Furthemore, using a clustering analysis, we analyze the ultrametric properties of phase space for this model.

  14. Strategy for automatic and complete three-dimensional optical digitization

    OpenAIRE

    2012-01-01

    This Letter proposes a new strategy of a three-dimensional (3D) scanning pipeline to achieve complete 3D digitization of complex objects in a real scene. This strategy consists of a one-dimensional array of optical 3D sensors combined with an automatically controlled turntable. An efficient calibration method for the sensor array is presented to guarantee the accuracy of the 3D measurement. Furthermore, an automatic registration technique is also proposed for aligning multiple range images ta...

  15. Entropy of three-dimensional BTZ black holes

    Institute of Scientific and Technical Information of China (English)

    GAO; Changjun; SHEN; Yougen

    2004-01-01

    The entropies of scalar field and neutrino field are calculated in the back ground of three-dimensional BTZ black hole.Considering statistical physics,we propose not to consider the superraradiant modes for bosons(Fermion fields do not displaysup perradiance).In fact,the nonsuperradiant modes do contribute exactly the area entropy for both bosons and fermions.The result shows that the neutrino field entropy is 3/2 times the scalar one.

  16. Three-Dimensional Simulations of Deep-Water Breaking Waves

    CERN Document Server

    Brucker, Kyle A; Dommermuth, Douglas G; Adams, Paul

    2014-01-01

    The formulation of a canonical deep-water breaking wave problem is introduced, and the results of a set of three-dimensional numerical simulations for deep-water breaking waves are presented. In this paper fully nonlinear progressive waves are generated by applying a normal stress to the free surface. Precise control of the forcing allows for a systematic study of four types of deep-water breaking waves, characterized herein as weak plunging, plunging, strong plunging, and very strong plunging.

  17. Development of three-dimensional memory (3D-M)

    Science.gov (United States)

    Yu, Hong-Yu; Shen, Chen; Jiang, Lingli; Dong, Bin; Zhang, Guobiao

    2016-10-01

    Since the invention of 3-D ROM in 1996, three-dimensional memory (3D-M) has been under development for nearly two decades. In this presentation, we'll review the 3D-M history and compare different 3D-Ms (including 3D-OTP from Matrix Semiconductor, 3D-NAND from Samsung and 3D-XPoint from Intel/Micron).

  18. Three dimensional momentum distributions of recoil-ions and photoelectrons

    Energy Technology Data Exchange (ETDEWEB)

    Ullrich, J.; Schmitt, W. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Doerner, R.; Jagutzki, O.; Mergel, V.; Moshammer, R.; Schmidt-Boecking, H.; Spielberger, L.; Unverzagt, M.; Vogt, T. [Frankfurt Univ. (Germany). Inst. fuer Kernphysik

    1996-10-01

    A novel high-resolution technique, the Multi-Electron-Recoil-Ion Momentum Spectroscopy, allows to determine in coincidence the three dimensional momentum vectors of the ion and up to three electrons created in any photo ionization event. At a solid angle of 4 {pi} the energy-resolutions for ions and electrons are {+-}2{mu} eV and {+-}10 meV, respectively. (orig.)

  19. Three-dimensional surface reconstruction from multistatic SAR images.

    Science.gov (United States)

    Rigling, Brian D; Moses, Randolph L

    2005-08-01

    This paper discusses reconstruction of three-dimensional surfaces from multiple bistatic synthetic aperture radar (SAR) images. Techniques for surface reconstruction from multiple monostatic SAR images already exist, including interferometric processing and stereo SAR. We generalize these methods to obtain algorithms for bistatic interferometric SAR and bistatic stereo SAR. We also propose a framework for predicting the performance of our multistatic stereo SAR algorithm, and, from this framework, we suggest a metric for use in planning strategic deployment of multistatic assets.

  20. Sectional and Ricci Curvature for Three-Dimensional Lie Groups

    Directory of Open Access Journals (Sweden)

    Gerard Thompson

    2016-01-01

    Full Text Available Formulas for the Riemann and Ricci curvature tensors of an invariant metric on a Lie group are determined. The results are applied to a systematic study of the curvature properties of invariant metrics on three-dimensional Lie groups. In each case the metric is reduced by using the automorphism group of the associated Lie algebra. In particular, the maximum and minimum values of the sectional curvature function are determined.