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Magyarul

Selected Publications of the Department of Image Processing and Computer Graphics of the year 2002

Articles in journal or book chapters

1. Erich Sorantin, Emese Balogh, Anna Vilanova i Bartroli, Kalman Palagyi, Laszlo G. Nyul, Sven Loncaric, Marko Subasic, and Domagoj Kovacevic. Virtual Dissection of the Colon. In D. Caramella, editor, 3D Image Processing -- Techniques and Clinical Applications, pages 197-209. Springer Verlag, Heidelberg, February 2002.
   
   @INCOLLECTION{Sorantin:2002:VDC,
   AUTHOR = {Erich Sorantin and Emese Balogh and Vilanova i Bartroli, Anna and Kalman Palagyi and Laszlo G. Nyul and Sven Loncaric and Marko Subasic and Domagoj Kovacevic},
   BOOKTITLE = {3D Image Processing -- Techniques and Clinical Applications},
   PUBLISHER = {Springer Verlag},
   TITLE = {Virtual Dissection of the Colon},
   YEAR = {2002},
   ADDRESS = {Heidelberg},
   EDITOR = {D. Caramella},
   MONTH = {February},
   PAGES = {197--209},
   }


2. Marianna Dudasne-Nagy, Eors Mate, and Bela Kari. Mathematical generation of normal data for evaluating myocardial perfusion studies. IEEE Transactions on Medical Imaging, 21:1358- 1365, 2002. [PDF] [doi:10.1109/TMI.2002.806429]
   Abstract: In this paper, we present a new mathematical method that synthesizes normal data sets for quantification of regional myocardium perfusion. In clinical practice, regional myocardial perfusion is often measured with a gamma camera and quantified via circumferential profile analysis. Normal reference profile data is used to increase the accuracy of the clinical interpretations. Our goal is to create reference data from an existing set of archived studies. An iterative mathematical method, based on two statistical hypotheses, was used to generate the study set instead of collecting normal examinations from a healthy population. Clinical validation is based on interpretations by six independent observers. Results of evaluation with synthesized normal data and its validation are presented.
   
   @ARTICLE{Dudasne-Nagy2002,
   AUTHOR = {Marianna Dudasne-Nagy and Eors Mate and Bela Kari},
   JOURNAL = {IEEE Transactions on Medical Imaging},
   TITLE = {Mathematical generation of normal data for evaluating myocardial perfusion studies},
   YEAR = {2002},
   PAGES = {1358- 1365},
   VOLUME = {21},
   DOI = {10.1109/TMI.2002.806429},
   }


3. Gabor Fichtinger, Theodore L. DeWeese, Alexandru Patriciu, Attila Tanacs, Dumitru Mazilu, James H. Anderson, Ken Masamune, Russel H. Taylor, and Dan Stoianovici. System for Robotically Assisted Prostate Biopsy and Therapy with Intraoperative CT Guidance. Academic Radiology, 9(1):60-74, 2002. [PDF] [doi:10.1016/S1076-6332(03)80297-0]
   Abstract: {\bf Rationale and Objectives}. The purpose of this study was to assess the work-in-progress prototype of an image-guided, robotic system for accurate and consistent placement of transperineal needles into the prostate with intraoperative image guidance inside the gantry of a computed tomographic (CT) scanner. {\bf Materials and Methods.} The coach-mounted system consists of a seven-degrees-of-freedom, passive mounting arm; a remote-center-of-motion robot; and a motorized, radiolucent needle-insertion device to deliver 17--18-gauge implant and biopsy needles into the prostate with the transperineal route. The robot is registered to the image space with a stereotactic adapter. The surgeon plans and controls the intervention in the CT scanner room with a desktop computer that receives DICOM images from the CT scanner. The complete system fits in a carry-on suitcase, does not need calibration, and does not utilize vendor-specific features of the CT scanner. {\bf Results.} In open air, the average accuracy was better than 1 mm at a 5--8-cm depth. In various phantoms, the average orientation error was 1.3 degrees, and the average distance between the needle tip and the target was 2 mm. {\bf Conclusion.} Results of preliminary experiments indicate that this robotic system may be suitable for transperineal needle placement into the prostate and shows potential in a variety of other percutaneous clinical applications.
   
   @ARTICLE{Fichtinger:2002:AcadRad,
   AUTHOR = {Gabor Fichtinger and Theodore L. DeWeese and Alexandru Patriciu and Attila Tanacs and Dumitru Mazilu and James H. Anderson and Ken Masamune and Russel H. Taylor and Dan Stoianovici},
   JOURNAL = {Academic Radiology},
   TITLE = {System for Robotically Assisted Prostate Biopsy and Therapy with Intraoperative CT Guidance},
   YEAR = {2002},
   NUMBER = {1},
   PAGES = {60--74},
   VOLUME = {9},
   DOI = {10.1016/S1076-6332(03)80297-0},
   }


4. Attila Kuba and Emese Balogh. Reconstruction of convex 2D discrete sets in polynomial time. Theoretical Computer Science, 283:223-242, June 2002. [doi:10.1016/S0304-3975(01)00080-9]
   Abstract: The reconstruction problem is considered in those classes of discrete sets where the reconstruction can be performed from two projections in polynomial time. The reconstruction algorithms and complexity results are summarized in the case of hv-convex sets, hv-convex 8-connected sets, hv-convex polyominoes, and directed h-convex sets. As new results some properties of the feet and spines of the hv-convex 8-connected sets are proven and it is shown that the spine of such a set can be determined from the projections in linear time. Two algorithms are given to reconstruct hv-convex 8-connected sets. Finally, it is shown that the directed h-convex sets are uniquely reconstructible with respect to their row and column sum vectors.
   
   @ARTICLE{Kuba2002,
   AUTHOR = {Attila Kuba and Emese Balogh},
   JOURNAL = {Theoretical Computer Science},
   TITLE = {Reconstruction of convex 2D discrete sets in polynomial time},
   YEAR = {2002},
   MONTH = {June},
   PAGES = {223-242},
   VOLUME = {283},
   DOI = {10.1016/S0304-3975(01)00080-9},
   }


5. Laszlo G. Nyul, Alexandre X. Falcao, and Jayaram K. Udupa. Fuzzy-Connected 3D Object Segmentation at Interactive Speeds. Graphical Models, 64(5):258-281, September 2002. [PDF] [doi:10.1016/S1077-3169(02)00005-9]
   Abstract: Image segmentation techniques using fuzzy connectedness principles have shown their effectiveness in segmenting a variety of objects in several large applications in recent years. However, one problem with these algorithms has been their excessive computational requirements. In an attempt to substantially speed them up, in the present paper, we study systematically a host of 18 'optimal' graph search algorithms. Extensive testing of these algorithms on a variety of 3D medical images taken from large ongoing applications demonstrates that a 20-1000-fold improvement over current speeds is achievable with a combination of algorithms and fast modern PCs. Utilizing efficient algorithms and careful selection of implementations can speed up the computation of fuzzy connectedness values by a factor of 16-29 (on the same hardware), as compared to the implementation previously used in our applications utilizing fuzzy object segmentation. The optimality of an algorithm depends on the input data as well as on the choice of the fuzzy affinity relation. The running time is reduced considerably (by a factor up to 34 for brain MR and even more for bone CT), when the algorithms make use of predetermined thresholds for the fuzzy objects. The reliable recognition (assisted by human operators) and the accurate, efficient, and sophisticated delineation (automatically performed by the computer) can be effectively incorporated into a single interactive process. If images having intensities with tissue-specific meaning (such as CT or standardized MR images) are utilized, most of the parameters for the segmentation method can be fixed once for all, all intermediate data (feature and fuzzy affinity values for the whole scene) can be computed before the user interaction is needed and the user can be provided with more information at the time of interaction.
   
   @ARTICLE{Nyul:2002:FC3,
   AUTHOR = {Laszlo G. Nyul and Alexandre X. Falcao and Jayaram K. Udupa},
   JOURNAL = {Graphical Models},
   TITLE = {Fuzzy-Connected 3D Object Segmentation at Interactive Speeds},
   YEAR = {2002},
   MONTH = {September},
   NUMBER = {5},
   PAGES = {258--281},
   VOLUME = {64},
   DOI = {10.1016/S1077-3169(02)00005-9},
   }


6. Kalman Palagyi. A 3-subiteration 3D thinning algorithm for extracting medial surfaces. Pattern Recognition Letters, 23:663-675, 2002. [PDF]
   Abstract: Thinning is an iterative layer by layer erosion for extracting skeletons. This paper presents an effcient 3D parallel thinning algorithm which produces medial surfaces. A 3-subiteration strategy is proposed: the thinning operation is changed from iteration to iteration with a period of 3 according to the three deletion directions.
   
   @ARTICLE{PalagyiPRL2002,
   AUTHOR = {Kalman Palagyi},
   JOURNAL = {Pattern Recognition Letters},
   TITLE = {A 3-subiteration 3D thinning algorithm for extracting medial surfaces},
   YEAR = {2002},
   PAGES = {663-675},
   VOLUME = {23},
   }


7. Erich Sorantin, Csongor Halmai, Balazs Erdohelyi, Kalman Palagyi, Laszlo G. Nyul, Krisztian Olle, Bernhard Geiger, Franz Lindbichler, Gerhard Friedrich, and Karl Kiesler. Spiral-CT-based Assessment of Tracheal Stenoses Using 3-D-skeletonization. IEEE Transactions on Medical Imaging, 21(3):263-273, March 2002. [PDF]
   Abstract: Purpose: Demonstration of a technique for three-dimensional (3-D) assessment of tracheal-stenoses, regarding site, length and degree, based on spiral computed tomography (S-CT). Patients and Methods: S-CT scanning and automated segmentation of the laryngo-tracheal tract (LTT) was followed by the extraction of the LTT medial axis using a skeletonization algorithm. Orthogonal to the medial axis the LTT 3-D cross-sectional profile was computed and presented as line charts, where degree and length was obtained. Values for both parameters were compared between 36 patients and 18 normal controls separately. Accuracy and precision was derived from 17 phantom studies. Results: Average degree and length of tracheal stenoses was found to be 60.5% and 4.32 cm in patients compared with minor caliber changes of 8.8% and 2.31 cm in normal controls ( p<0.0001). For the phantoms an excellent correlation between the true and computed 3-D cross-sectional profile was found ( p < 0.005) and an accuracy for length and degree measurements of 2.14 mm and 2.53% respectively could be determined. The corresponding figures for the precision were found to be 0.92 mm and 2.56%. Conclusion: LTT 3-D cross-sectional profiles permit objective, accurate and precise assessment of LTT caliber changes. Minor LTT caliber changes can be observed even in normals and, in case of an otherwise normal S-CT study, can be regarded as artifacts.
   
   @ARTICLE{Sorantin:2002:SAT,
   AUTHOR = {Erich Sorantin and Csongor Halmai and Balazs Erdohelyi and Kalman Palagyi and Laszlo G. Nyul and Krisztian Olle and Bernhard Geiger and Franz Lindbichler and Gerhard Friedrich and Karl Kiesler},
   JOURNAL = {IEEE Transactions on Medical Imaging},
   TITLE = {Spiral-CT-based Assessment of Tracheal Stenoses Using 3-D-skeletonization},
   YEAR = {2002},
   MONTH = {March},
   NUMBER = {3},
   PAGES = {263--273},
   VOLUME = {21},
   }


8. Erich Sorantin, Georg Werkgartner, Emese Balogh, Anna Vilanova i Bartroli, Kalman Palagyi, Laszlo G. Nyul, and Laszlo Rusko. Virtual dissection and automated polyp detection of the colon based on spiral CT data --- Techniques and preliminary experience on a cadaveric phantom. European Surgery -- Acta Chirurgica Austriaca, 34:143-149, 2002. [WWW] [doi:10.1046/j.1563-2563.2002.02018.x]
   Abstract: Background: CT colonography was found to be sensitive and specific for detection of colonic polyps and colorectal cancer (CRC). Depending on the software used, CT colonography requires a certain amount of operator interaction, which limits it's widespread usage. The goal of this papers is to present two novel automated techniques for displaying CT colonography: virtual dissection and automated colonic polyp detection. Methods: Virtual dissection refers to a technique where the entire colon is virtually stretched and flattened thus simulating the view on the pathologist's table. Colonic folds show a ``global outward bulging of the contour'', whereas colonic polyps exhibit the inverse (``local inward bulging''). This feature is used to map areas of ``local inward bulging'' with colours on 3D reconstructions. A cadaveric phantom with 13 artificially inserted polyps was used for validation of both techniques. Results: On virtual dissection all 13 inserted polyps could be identified. They appeared either as bumps or as local broadening of colonic folds. In addition, the automated colonic polyp detection algorithm was able to tag all polyps. Only 10 min of operator interaction were necessary for both techniques. Conclusions: Virtual dissection overcomes the shortcomings of CT colonography, and automated colonic polyp detection establishes a roadmap of the polyps.
   
   @ARTICLE{SorantinEtalACA2002,
   AUTHOR = {Erich Sorantin and Georg Werkgartner and Emese Balogh and Vilanova i Bartroli, Anna and Kalman Palagyi and Laszlo G. Nyul and Laszlo Rusko},
   JOURNAL = {European Surgery -- Acta Chirurgica Austriaca},
   TITLE = {Virtual dissection and automated polyp detection of the colon based on spiral CT data --- Techniques and preliminary experience on a cadaveric phantom},
   YEAR = {2002},
   PAGES = {143-149},
   VOLUME = {34},
   URL = {http://www.blackwell-synergy.com/doi/abs/10.1046/j.1563-2563.2002.02018.x},
   DOI = {10.1046/j.1563-2563.2002.02018.x},
   }


9. Josiane Zerubia, Andre Jalobeanu, and Zoltan Kato. Markov random fields in image processing, application to remote sensing and astrophysics. Journal de Physique, EDP Sciences, IV(12):117-136, 2002. [WWW]
   
   @ARTICLE{Zerubia-etal2002,
   AUTHOR = {Josiane Zerubia and Andre Jalobeanu and Zoltan Kato},
   JOURNAL = {Journal de Physique, EDP Sciences},
   TITLE = {Markov random fields in image processing, application to remote sensing and astrophysics},
   YEAR = {2002},
   NUMBER = {12},
   PAGES = {117--136},
   VOLUME = {IV},
   URL = {http://www.edpsciences.org/articles/jp4/abs/2002/01/jp4pr1p117/jp4pr1p117.html},
   }

Conference articles

1. Emese Balogh, Erich Sorantin, Laszlo G. Nyul, Kalman Palagyi, Attila Kuba, Georg Werkgartner, and Ekke Spuller. Virtual Dissection of the Colon -- Technique and First Experiments with Artificial and Cadaveric Phantoms. In S. K. Mun, editor, Proceedings of Medical Imaging 2002: Visualization, Image-Guided Procedures, and Display, volume 4681 of SPIE Proceedings, San Diego, USA, pages 713-721, May 2002. SPIE. [doi:10.1117/12.466982]
   Abstract: Virtual dissection refers to a display technique for polyp detection, where the colon is digitally straightened and then flattened using multirow detector Computed Tomograph (CT) images. As compared to virtual colonoscopy where polyps may be hidden from view behind the folds, the unravelled colon is more suitable for polyp detection, because the entire inner surface of the colon is displayed in a single view. The method was tested both on artificial and cadaveric phantoms. All polyps could be recognized on both phantoms. This technique for virtual dissection requires only a minimum of operator interaction.
   
   @INPROCEEDINGS{Balogh:2002:VDC,
   AUTHOR = {Emese Balogh and Erich Sorantin and Laszlo G. Nyul and Kalman Palagyi and Attila Kuba and Georg Werkgartner and Ekke Spuller},
   BOOKTITLE = {Proceedings of Medical Imaging 2002: Visualization, Image-Guided Procedures, and Display},
   TITLE = {Virtual Dissection of the Colon -- Technique and First Experiments with Artificial and Cadaveric Phantoms},
   YEAR = {2002},
   ADDRESS = {San Diego, USA},
   EDITOR = {S. K. Mun},
   MONTH = {May},
   PAGES = {713--721},
   PUBLISHER = {SPIE},
   SERIES = {SPIE Proceedings},
   VOLUME = {4681},
   DOI = {10.1117/12.466982},
   }


2. Gabor Fichtinger, Axel Krieger, Robert C. Susil, Attila Tanacs, Louis L. Whitcomb, and Ergin Atalar. Transrectal prostate biopsy inside closed MRI scanner with remote actuation, under real-time image guidance. In Takeyoshi Dohi and Ron Kikins, editors, Proceedings of the International Conference on Medical Image Computing & Computer Assisted Intervention (MICCAI), volume 2488 (1) of Lecture Notes in Computer Science, Tokyo, Japan, pages 91-98, September 2002. [PDF]
   Abstract: We present the proof-of-concept prototype of a prostate biopsy robot to be used inside a conventional high-field MRI scanner. A three degree-of-freedom (DOF) mechanical device translates and rotates inside the rectum and enters a needle into the body, and steers the needle to a target point pre-selected by the user. The device is guided by real-time images from the scanner. Networked computers process the medical images and enable the clinician to control the motion of the mechanical device that is operated remotely from outside the imager. The system is also applicable to localized prostate therapy and also demonstrates potential in other intra-cavitary procedures.
   
   @INPROCEEDINGS{Fichtinger:2002:MICCAI,
   AUTHOR = {Gabor Fichtinger and Axel Krieger and Robert C. Susil and Attila Tanacs and Louis L. Whitcomb and Ergin Atalar},
   BOOKTITLE = {Proceedings of the International Conference on Medical Image Computing & Computer Assisted Intervention (MICCAI)},
   TITLE = {Transrectal prostate biopsy inside closed MRI scanner with remote actuation, under real-time image guidance},
   YEAR = {2002},
   ADDRESS = {Tokyo, Japan},
   EDITOR = {Takeyoshi Dohi and Ron Kikins},
   MONTH = {September},
   PAGES = {91--98},
   SERIES = {Lecture Notes in Computer Science},
   VOLUME = {2488 (1)},
   }


3. Zoltan Kato, Xiaowen Ji, Tamas Sziranyi, Zoltan Toth, and Laszlo Czuni. Content-Based Image Retrieval Using Stochastic Paintbrush Transformation. In Proceedings of the International Conference on Image Processing, volume 1, New York, USA, pages 944-947, September 2002. IEEE. [PDF] [PS]
   Abstract: We propose a new content based image retrieval method. The novelty of our approach lies in the applied image similarity measure: unlike traditional features, such as color, texture or shape, our measure is based on a painted representation of the original image. We use paintbrush stroke parameters as features. These strokes are produced by a stochastic paintbrush algorithm which simulates a painting process. Stroke parameters include color, orientation and location. Therefore, it provides information not only about the color content but also about the structural properties of an image. Experimental results on a database of more than 500 images show that the CBIR method using paintbrush features has a higher retrieval rate than methods using color features only.
   
   @INPROCEEDINGS{Kato-etal2002a,
   AUTHOR = {Zoltan Kato and Xiaowen Ji and Tamas Sziranyi and Zoltan Toth and Laszlo Czuni},
   BOOKTITLE = {Proceedings of the International Conference on Image Processing},
   TITLE = {Content-Based Image Retrieval Using Stochastic Paintbrush Transformation},
   YEAR = {2002},
   ADDRESS = {New York, USA},
   MONTH = {September},
   ORGANIZATION = {IEEE},
   PAGES = {944-947},
   VOLUME = {1},
   PS = {../papers/icip2002.ps},
   }


4. Zoltan Kato, Ting Chuen Pong, and Guo Qiang Song. Multicue MRF Image Segmentation: Combining Texture and Color. In Proceedings of the International Conference on Pattern Recognition, volume 1, Quebec, Canada, pages 660-663, August 2002. IAPR, IEEE. [PDF] [PS]
   Abstract: We propose a new Markov random field (MRF) image segmentation model which aims at combining color and texture features. The model has a multilayer structure: each feature has its own layer, called feature layer, where an MRF model is defined using only the corresponding feature. A special layer is assigned to the combined MRF model. This layer interacts with each feature layer and provides the segmentation based on the combination of different features. The uniqueness of our algorithm is that it provides both color only and texture only segmentations as well as a segmentation based on combined color and texture features. The number of classes on feature layers is given by the user, but it is estimated on the combined layer.
   
   @INPROCEEDINGS{Kato-etal2002,
   AUTHOR = {Zoltan Kato and Ting Chuen Pong and Guo Qiang Song},
   BOOKTITLE = {Proceedings of the International Conference on Pattern Recognition},
   TITLE = {Multicue MRF Image Segmentation: Combining Texture and Color},
   YEAR = {2002},
   ADDRESS = {Quebec, Canada},
   MONTH = {August},
   ORGANIZATION = {IAPR},
   PAGES = {660-663},
   PUBLISHER = {IEEE},
   VOLUME = {1},
   PS = {../papers/icpr2002.ps},
   }


5. Laszlo G. Nyul and Jayaram K. Udupa. A Protocol-independent Brain MRI Segmentation Method. In M. Sonka and J. M. Fitzpatrick, editors, Proceedings of Medical Imaging 2002: Image Processing, volume 4684 of SPIE Proceedings, San Diego, USA, pages 1588-1599, May 2002. [PDF]
   Abstract: We present a segmentation method that combines the robust, accurate, and efficient techniques of fuzzy connectedness with standardized MRI intensities and fast algorithms. The result is a general segmentation framework that more efficiently utilizes the user input (for recognition) and the power of computer (for delineation). This same method has been applied to segment brain tissues from a variety of MRI protocols. Images were corrected for inhomogeneity and standardized to yield tissue-specific intensity values. All parameters for the fuzzy affinity relations were fixed for a specific input protocol. Scale-based fuzzy affinity was used to better capture fine structures. Brain tissues were segmented as 3D fuzzy-connected objects by using relative fuzzy connectedness. The user can specify seed points in about a minute and tracking the 3D fuzzy-connected objects takes about 20 seconds per object. All other computations were performed before any user interaction took place. Segmentation of brain tissues as 3D fuzzy-connected objects from MRI data is feasible at interactive speeds. Utilizing the robust fuzzy connectedness principles and fast algorithms, it is possible to interactively select fuzzy affinity, seed point, and threshold parameters and perform efficient, precise, and accurate segmentations.
   
   @INPROCEEDINGS{Nyul:2002:PBM,
   AUTHOR = {Laszlo G. Nyul and Jayaram K. Udupa},
   BOOKTITLE = {Proceedings of Medical Imaging 2002: Image Processing},
   TITLE = {A Protocol-independent Brain MRI Segmentation Method},
   YEAR = {2002},
   ADDRESS = {San Diego, USA},
   EDITOR = {M. Sonka and J. M. Fitzpatrick},
   MONTH = {May},
   PAGES = {1588--1599},
   SERIES = {SPIE Proceedings},
   VOLUME = {4684},
   }


6. Juerg Tschirren, Kalman Palagyi, Joseph M. Reinhardt, Eric A. Hoffman, and Milan Sonka. Segmentation, skeletonization, and branchpoint matching - A fully automated quantitative evaluation of human intrathoratic airway trees. In Takeyoshi Dohi and Ron Kikinis, editors, Proceedings of the International Conference on Medical Image Computing & Computer Assisted Intervention (MICCAI), volume 2489 of Lecture Notes in Computer Science, Tokyo, Japan, pages 12-19, September 2002. Springer Verlag. [PDF]
   Abstract: Modern multislice X-ray CT scanners provide high-resolution volumetric image data containing a wealth of structural and functional information. The size of the volumes makes it more and more di?cult for human observers to visually evaluate their contents. Similar to other areas of medical image analysis, highly automated extraction and quantitative assessment of volumetric data is increasingly important in pulmonary physiology, diagnosis, and treatment. We present a method for a fully automated segmentation of a human airway tree, its skeletonization, identi?cation of airway branches and branchpoints, as well as a method for matching the airway trees, branches, and branchpoints for the same subject over time and across subjects. The validation of our method shows a high correlation between the automatically obtained results and reference data provided by human observers.
   
   @INPROCEEDINGS{TschirrenEtalMICCAI2002,
   AUTHOR = {Juerg Tschirren and Kalman Palagyi and Joseph M. Reinhardt and Eric A. Hoffman and Milan Sonka},
   BOOKTITLE = {Proceedings of the International Conference on Medical Image Computing & Computer Assisted Intervention (MICCAI)},
   TITLE = {Segmentation, skeletonization, and branchpoint matching - A fully automated quantitative evaluation of human intrathoratic airway trees},
   YEAR = {2002},
   ADDRESS = {Tokyo, Japan},
   EDITOR = {Takeyoshi Dohi and Ron Kikinis},
   MONTH = {September},
   PAGES = {12-19},
   PUBLISHER = {Springer Verlag},
   SERIES = {Lecture Notes in Computer Science},
   VOLUME = {2489},
   }

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