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Author Maurizio Mencuccini; Jordi Martinez-Vilalta; Josep Piñol; Lasse Loepfe; Mireia Burnat ; Xavier Alvarez; Juan Camacho; Debora Gil
Title A quantitative and statistically robust method for the determination of xylem conduit spatial distribution Type Journal Article
Year 2010 Publication American Journal of Botany Abbreviated Journal AJB
Volume 97 Issue 8 Pages 1247-1259
Keywords Geyer; hydraulic conductivity; point pattern analysis; Ripley; Spatstat; vessel clusters; xylem anatomy; xylem network
Abstract Premise of the study: Because of their limited length, xylem conduits need to connect to each other to maintain water transport from roots to leaves. Conduit spatial distribution in a cross section plays an important role in aiding this connectivity. While indices of conduit spatial distribution already exist, they are not well defined statistically. * Methods: We used point pattern analysis to derive new spatial indices. One hundred and five cross-sectional images from different species were transformed into binary images. The resulting point patterns, based on the locations of the conduit centers-of-area, were analyzed to determine whether they departed from randomness. Conduit distribution was then modeled using a spatially explicit stochastic model. * Key results: The presence of conduit randomness, uniformity, or aggregation depended on the spatial scale of the analysis. The large majority of the images showed patterns significantly different from randomness at least at one spatial scale. A strong phylogenetic signal was detected in the spatial variables. * Conclusions: Conduit spatial arrangement has been largely conserved during evolution, especially at small spatial scales. Species in which conduits were aggregated in clusters had a lower conduit density compared to those with uniform distribution. Statistically sound spatial indices must be employed as an aid in the characterization of distributional patterns across species and in models of xylem water transport. Point pattern analysis is a very useful tool in identifying spatial patterns.
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Publisher Place of Publication (down) Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
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ISSN ISBN Medium
Area Expedition Conference
Notes IAM; Approved no
Call Number IAM @ iam @ MMG2010 Serial 1623
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Author J.A.Perez; Enric Marti; Juan J.Villanueva
Title Interfase de Usuario de Entrada de Datos 3D en un CAD de Cartografía Urbana a partir de Pares Estereoscópicos Type Conference Article
Year 1992 Publication II Congreso Español de Informática Gráfica Abbreviated Journal
Volume Issue Pages 47-60
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Abstract
Address
Corporate Author Thesis
Publisher Place of Publication (down) Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference CEIG
Notes IAM;ISE Approved no
Call Number IAM @ iam @ PVM1992 Serial 1624
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Author Sandra Pujades;Francesc Carreras;Manuel Ballester; Jaume Garcia; Debora Gil
Title A Normalized Parametric Domain for the Analysis of the Left Ventricular Function Type Conference Article
Year 2008 Publication Proceedings of the Third International Conference on Computer Vision Theory and Applications (VISAPP’08) Abbreviated Journal
Volume 1 Issue Pages 267-274
Keywords Helical Ventricular Myocardial Band; Myocardial Fiber; Tagged Magnetic Resonance; HARP; Optical Flow Variational Framework; Gabor Filters; B-Splines.
Abstract Impairment of left ventricular (LV) contractility due to cardiovascular diseases is reflected in LV motion patterns. The mechanics of any muscle strongly depends on the spatial orientation of its muscular fibers since the motion that the muscle undergoes mainly takes place along the fiber. The helical ventricular myocardial band (HVMB) concept describes the myocardial muscle as a unique muscular band that twists in space in a non homogeneous fashion. The 3D anisotropy of the ventricular band fibers suggests a regional analysis of the heart motion. Computation of normality models of such motion can help in the detection and localization of any cardiac disorder. In this paper we introduce, for the first time, a normalized parametric domain that allows comparison of the left ventricle motion across patients. We address, both, extraction of the LV motion from Tagged Magnetic Resonance images, as well as, defining a mapping of the LV to a common normalized domain. Extraction of normality motion patterns from 17 healthy volunteers shows the clinical potential of our LV parametrization.
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Publisher Place of Publication (down) Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes IAM; Approved no
Call Number IAM @ iam @ GGP2008 Serial 1627
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Author Petia Radeva; A.Amini; J.Huang; Enric Marti
Title Deformable B-Solids and Implicit Snakes for Localization and Tracking of SPAMM MRI-Data Type Conference Article
Year 1996 Publication Workshop on Mathematical Methods in Biomedical Image Analysis Abbreviated Journal
Volume Issue Pages 192-201
Keywords
Abstract To date, MRI-SPAMM data from different image slices have been analyzed independently. In this paper, we propose an approach for 3D tag localization and tracking of SPAMM data by a novel deformable B-solid. The solid is defined in terms of a 3D tensor product B-spline. The isoparametric curves of the B-spline solid have special importance. These are termed implicit snakes as they deform under image forces from tag lines in different image slices. The localization and tracking of tag lines is performed under constraints of continuity and smoothness of the B-solid. The framework unifies the problems of localization, and displacement fitting and interpolation into the same procedure utilizing B-spline bases for interpolation. To track motion from boundaries and restrict image forces to the myocardium, a volumetric model is employed as a pair of coupled endocardial and epicardial B-spline surfaces. To recover deformations in the LV an energy-minimization problem is posed where both tag and ...
Address San Francisco CA
Corporate Author Thesis
Publisher IEEE Computer Society Place of Publication (down) Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN 0-8186-7368-0 Medium
Area Expedition Conference MMBIA ’96
Notes MILAB;IAM; Approved no
Call Number IAM @ iam @ RAH1996 Serial 1630
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Author Petia Radeva; Amir Amini; Jintao Huang; Enric Marti
Title Deformable B-Solids: application for localization and tracking of MRI-SPAMM data Type Report
Year 1996 Publication CVC Technical Report Abbreviated Journal
Volume Issue 8 Pages
Keywords
Abstract To date, MRI-SPAMM data from different image slices have been analyzed independently. In this paper, we propose an approach for 3D tag localization and tracking of SPAMM data by a novel deformable B-solid. The solid is defined in terms of a 3D tensor product B-spline. The isoparametric curves of the B-spline solid have special importance. These are termed implicit snakes as they deform under image forces from tag lines in different image slices. The localization and tracking of tag lines is performed under constraints of continuity and smoothness of the B-solid. The framework unifies the problems of localization, and displacement fitting and interpolation into the same procedure utilizing B-spline bases for interpolation. To track motion from boundaries and restrict image forces to the myocardium, a volumetric model is employed as a pair of coupled endocardial and epicardial B-spline surfaces. To recover deformations in the LV an energy-minimization problem is posed where both tag and ...
Address
Corporate Author Thesis
Publisher CVC (UAB) Place of Publication (down) Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes MILAB;IAM Approved no
Call Number IAM @ iam @ RHM1996 Serial 1631
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Author Petia Radeva; Enric Marti
Title An improved model of snakes for model-based segmentation Type Conference Article
Year 1995 Publication Proceedings of Computer Analysis of Images and Patterns Abbreviated Journal
Volume Issue Pages 515-520
Keywords
Abstract The main advantage of segmentation by snakes consists in its ability to incorporate smoothness constraints on the detected shapes that can occur. Likewise, we propose to model snakes with other properties that reflect the information provided about the object of interest in a different extent. We consider different kinds of snakes, those searching for contours with a certain direction, those preserving an object’s model, those seeking for symmetry, those expanding open, etc. The availability of such a collection of snakes allows not only the more complete use of the knowledge about the segmented object, but also to solve some problems of the existing snakes. Our experiments on segmentation of facial features justify the usefulness of snakes with different properties.
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Publisher Place of Publication (down) Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference CAIP
Notes MILAB;IAM Approved no
Call Number IAM @ iam @ RaM1995b Serial 1632
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Author Petia Radeva; Joan Serrat; Enric Marti
Title A snake for model-based segmentation Type Conference Article
Year 1995 Publication Proc. Conf. Fifth Int Computer Vision Abbreviated Journal
Volume Issue Pages 816-821
Keywords snakes; elastic matching; model-based segmenta tion
Abstract Despite the promising results of numerous applications, the hitherto proposed snake techniques share some common problems: snake attraction by spurious edge points, snake degeneration (shrinking and attening), convergence and stability of the deformation process, snake initialization and local determination of the parameters of elasticity. We argue here that these problems can be solved only when all the snake aspects are considered. The snakes proposed here implement a new potential eld and external force in order to provide a deformation convergence, attraction by both near and far edges as well as snake behaviour selective according to the edge orientation. Furthermore, we conclude that in the case of model-based seg mentation, the internal force should include structural information about the expected snake shape. Experiments using this kind of snakes for segmenting bones in complex hand radiographs show a signi cant improvement.
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Publisher Place of Publication (down) Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes MILAB;ADAS;IAM Approved no
Call Number IAM @ iam @ RSM1995 Serial 1634
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Author Oriol Rodriguez-Leon.A.Carol;H.Tizon; Eduard Fernandez-Nofrerias; Josefina Mauri; Vicente del Valle; Debora Gil; Aura Hernandez-Sabate; Petia Radeva
Title Model estadístic-determinístic per la segmentació de l adventicia en imatges d ecografía intracoronaria Type Journal Article
Year 2005 Publication Rev Societat Catalana Cardiologia Abbreviated Journal
Volume 5 Issue Pages 41
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Publisher Place of Publication (down) Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes IAM;MILAB Approved no
Call Number IAM @ iam @ RCT2005 Serial 1637
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Author Oriol Rodriguez-Leon; Josefina Mauri; Eduard Fernandez-Nofrerias; M.Gomez; Antonio Tovar; L.Cano; C.Diego; Carme Julia; Vicente del Valle; Debora Gil; Petia Radeva
Title Ecografia Intracoronària: Segmentació Automàtica de area de la llum Type Conference Article
Year 2002 Publication XXXVIII Congreso Nacional de la Sociedad Española de Cardiología. Abbreviated Journal
Volume Issue Pages
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Abstract
Address
Corporate Author Thesis
Publisher Place of Publication (down) Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes IAM;ADAS;MILAB Approved no
Call Number IAM @ iam @ RMF2002 Serial 1638
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Author Oriol Rodriguez-Leon; Debora Gil; Eduard Fernandez-Nofrerias
Title Analisis en los cambios en el nivel de gris en las secuencias angiograficas mediante descriptores estadisticos para determinar la perfusion miocardica Type Journal Article
Year 2006 Publication Revista Española de Cardiología Abbreviated Journal REC
Volume 59 Supl 2-166 Issue 2 Pages 128
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Abstract
Address
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Publisher Place of Publication (down) Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes IAM; Approved no
Call Number IAM @ iam @ RGF2006 Serial 1640
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Author Oriol Rodriguez-Leon; Josefina Mauri;Eduard Fernandez-Nofrerias; C.Garcia; R.Villuendas; Vicente del Valle; Debora Gil;Petia Radeva
Title Reconstruction of a spatio-temporal model of the intima layer from intravascular ultrasound sequences Type Journal Article
Year 2003 Publication European Heart Journal Abbreviated Journal
Volume Issue Pages
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Address
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Publisher Place of Publication (down) Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference ESC Congress
Notes IAM;MILAB Approved no
Call Number IAM @ iam @ RMF2003c Serial 1641
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Author Oriol Rodriguez-Leon; Josefina Mauri;Eduard Fernandez-Nofrerias; Antonio Tovar; Vicente del Valle; Aura Hernandez-Sabate; Debora Gil; Petia Radeva
Title Utilización de la Estructura de los Campos Vectoriales para la Detección de la Adventicia en Imágenes de Ecografía Intracoronaria Type Journal Article
Year 2004 Publication Revista Internacional de Enfermedades Cardiovasculares Revista Española de Cardiología Abbreviated Journal
Volume 57 Issue 2 Pages 100
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Corporate Author Thesis
Publisher Place of Publication (down) Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
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ISSN ISBN Medium
Area Expedition Conference SEC
Notes IAM;MILAB Approved no
Call Number IAM @ iam @ RMF2004 Serial 1642
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Author Misael Rosales; Petia Radeva; Oriol Rodriguez; Debora Gil
Title Suppression of IVUS Image Rotation. A Kinematic Approach Type Book Chapter
Year 2005 Publication Functional Imaging and Modeling of the Heart Abbreviated Journal LNCS
Volume 3504 Issue Pages 889-892
Keywords
Abstract IntraVascular Ultrasound (IVUS) is an exploratory technique used in interventional procedures that shows cross section images of arteries and provides qualitative information about the causes and severity of the arterial lumen narrowing. Cross section analysis as well as visualization of plaque extension in a vessel segment during the catheter imaging pullback are the technique main advantages. However, IVUS sequence exhibits a periodic rotation artifact that makes difficult the longitudinal lesion inspection and hinders any segmentation algorithm. In this paper we propose a new kinematic method to estimate and remove the image rotation of IVUS images sequences. Results on several IVUS sequences show good results and prompt some of the clinical applications to vessel dynamics study, and relation to vessel pathology.
Address
Corporate Author Thesis
Publisher Springer Berlin / Heidelberg Place of Publication (down) Editor Frangi, Alejandro and Radeva, Petia and Santos, Andres and Hernandez, Monica
Language Summary Language Original Title
Series Editor Series Title Lecture Notes in Computer Science Abbreviated Series Title LNCS
Series Volume 3504 Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes IAM;MILAB Approved no
Call Number IAM @ iam @ RRR2005 Serial 1645
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Author Misael Rosales; Petia Radeva;Oriol Rodriguez-Leon; Debora Gil
Title Modelling of image-catheter motion for 3-D IVUS Type Journal Article
Year 2009 Publication Medical image analysis Abbreviated Journal MIA
Volume 13 Issue 1 Pages 91-104
Keywords Intravascular ultrasound (IVUS); Motion estimation; Motion decomposition; Fourier
Abstract Three-dimensional intravascular ultrasound (IVUS) allows to visualize and obtain volumetric measurements of coronary lesions through an exploration of the cross sections and longitudinal views of arteries. However, the visualization and subsequent morpho-geometric measurements in IVUS longitudinal cuts are subject to distortion caused by periodic image/vessel motion around the IVUS catheter. Usually, to overcome the image motion artifact ECG-gating and image-gated approaches are proposed, leading to slowing the pullback acquisition or disregarding part of IVUS data. In this paper, we argue that the image motion is due to 3-D vessel geometry as well as cardiac dynamics, and propose a dynamic model based on the tracking of an elliptical vessel approximation to recover the rigid transformation and align IVUS images without loosing any IVUS data. We report an extensive validation with synthetic simulated data and in vivo IVUS sequences of 30 patients achieving an average reduction of the image artifact of 97% in synthetic data and 79% in real-data. Our study shows that IVUS alignment improves longitudinal analysis of the IVUS data and is a necessary step towards accurate reconstruction and volumetric measurements of 3-D IVUS.
Address
Corporate Author Thesis
Publisher Place of Publication (down) Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes IAM;MILAB Approved no
Call Number IAM @ iam @ RRR2009 Serial 1646
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Author David Rotger; Misael Rosales; Jaume Garcia; Oriol Pujol ; Josefina Mauri; Petia Radeva
Title Active Vessel: A New Multimedia Workstation for Intravascular Ultrasound and Angiography Fusion Type Journal Article
Year 2003 Publication Computers in Cardiology Abbreviated Journal
Volume 30 Issue Pages 65-68
Keywords
Abstract AcriveVessel is a new multimedia workstation which enables the visualization, acquisition and handling of both image modalities, on- and ofline. It enables DICOM v3.0 decompression and browsing, video acquisition,repmduction and storage for IntraVascular UltraSound (IVUS) and angiograms with their corresponding ECG,automatic catheter segmentation in angiography images (using fast marching algorithm). BSpline models definition for vessel layers on IVUS images sequence and an extensively validated tool to fuse information. This approach defines the correspondence of every IVUS image with its correspondent point in the angiogram and viceversa. The 3 0 reconstruction of the NUS catheterhessel enables real distance measurements as well as threedimensional visualization showing vessel tortuosity in the space.
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Publisher Place of Publication (down) Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
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ISSN ISBN Medium
Area Expedition Conference
Notes IAM;MILAB;HuPBA Approved no
Call Number IAM @ iam @ RRG2003 Serial 1647
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