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Author Blume, M.; Martinez-Moller, A.; Keil, A.; Navab, N.; Rafecas, M.
Title Joint Reconstruction of Image and Motion in Gated Positron Emission Tomography Type Journal Article
Year 2010 Publication IEEE Transactions on Medical Imaging Abbreviated Journal IEEE Trans. Med. Imaging
Volume 29 Issue 11 Pages 1892-1906
Keywords Gating; motion compensation; positron emission tomography (PET); reconstruction
Abstract We present a novel intrinsic method for joint reconstruction of both image and motion in positron emission tomography (PET). Intrinsic motion compensation methods exclusively work on the measured data, without any external motion measurements. Most of these methods separate image from motion estimation: They use deformable image registration/optical flow techniques in order to estimate the motion from individually reconstructed gates. Then, the image is estimated based on this motion information. With these methods, a main problem lies in the motion estimation step, which is based on the noisy gated frames. The more noise is present, the more inaccurate the image registration becomes. As we show both visually and quantitatively, joint reconstruction using a simple deformation field motion model can compete with state-of-the-art image registration methods which use robust multilevel B-spline motion models.
Address [Blume, Moritz; Rafecas, Magdalena] Univ Valencia, CSIC, IFIC, E-46071 Valencia, Spain, Email: moritz.blume@cs.tum.edu
Corporate Author Thesis
Publisher Ieee-Inst Electrical Electronics Engineers Inc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition (up)
ISSN 0278-0062 ISBN Medium
Area Expedition Conference
Notes ISI:000283941800007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 340
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Author Borja, E.F.; Diaz-Polo, J.; Garay, I.; Livine, E.R.
Title Dynamics for a 2-vertex quantum gravity model Type Journal Article
Year 2010 Publication Classical and Quantum Gravity Abbreviated Journal Class. Quantum Gravity
Volume 27 Issue 23 Pages 235010 - 34pp
Keywords
Abstract We use the recently introduced U(N) framework for loop quantum gravity to study the dynamics of spin network states on the simplest class of graphs: two vertices linked with an arbitrary number N of edges. Such graphs represent two regions, in and out, separated by a boundary surface. We study the algebraic structure of the Hilbert space of spin networks from the U(N) perspective. In particular, we describe the algebra of operators acting on that space and discuss their relation to the standard holonomy operator of loop quantum gravity. Furthermore, we show that it is possible to make the restriction to the isotropic/homogeneous sector of the model by imposing the invariance under a global U(N) symmetry. We then propose a U(N)-invariant Hamiltonian operator and study the induced dynamics. Finally, we explore the analogies between this model and loop quantum cosmology and sketch some possible generalizations of it.
Address [Borja, Enrique F.; Garay, Inaki] Univ Erlangen Nurnberg, Inst Theoret Phys 3, D-91058 Erlangen, Germany, Email: etera.livine@ens-lyon.fr
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition (up)
ISSN 0264-9381 ISBN Medium
Area Expedition Conference
Notes ISI:000284211600011 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 341
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Author CDF Collaboration (Aaltonen, T. et al); Cabrera, S.
Title Measurement of the Lambda(0)(b) Lifetime in Lambda(0)(b) -> Lambda(+)(c)pi(-) Decays in p(p)over-bar Collisions at root s=1.96 TeV Type Journal Article
Year 2010 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 104 Issue 10 Pages 102002 - 8pp
Keywords
Abstract We report a measurement of the lifetime of the Lambda(0)(b) baryon in decays to the Lambda(+)(c)pi(-) final state in a sample corresponding to 1.1 fb(-1) collected in p (p) over bar collisions at root s = 1.96 TeV by the CDF II detector at the Tevatron collider. Using a sample of about 3000 fully reconstructed Lambda(0)(b) events we measure tau(Lambda(0)(b) ) = 1.401 +/- 0.046(stat) +/- 0.035(syst) ps (corresponding to c tau(Lambda(0)(b)) = 420.1 +/- 13.7(stat) +/- 10.6(syst) μm, where c is the speed of light). The ratio of this result and the world average B-0 lifetime yields tau(Lambda(0)(b))/tau(B-0) = 0.918 +/- 0.038 (stat) and (syst), in good agreement with recent theoretical predictions.
Address [Aaltonen, T.; Mehtala, P.; Orava, R.; Osterberg, K.; Saarikko, H.; van Remortel, N.] Univ Helsinki, Dept Phys, Div High Energy Phys, FIN-00014 Helsinki, Finland
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition (up)
ISSN 0031-9007 ISBN Medium
Area Expedition Conference
Notes ISI:000275543500011 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 294
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Author Tolos, L.; Molina, R.; Oset, E.; Ramos, A.
Title (K)over-bar* mesons in dense matter Type Journal Article
Year 2010 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 82 Issue 4 Pages 045210 - 12pp
Keywords
Abstract We study the properties of (K) over bar* mesons in nuclear matter using a unitary approach in coupled channels within the framework of the local hidden gauge formalism and incorporating the (K) over bar pi decay channel in matter. The in-medium (K) over bar *N interaction accounts for Pauli blocking effects and incorporates the (K) over bar* self-energy in a self-consistent manner. We also obtain the (K) over bar* (off-shell) spectral function and analyze its behavior at finite density and momentum. At a normal nuclear matter density, the (K) over bar* meson feels a moderately attractive potential, while the (K) over bar* width becomes five times larger than in free space. We estimate the transparency ratio of the gamma A -> K+K*(-) A` reaction, which we propose as a feasible scenario at the present facilities to detect changes in the properties of the (K) over bar* meson in nuclear medium.
Address [Tolos, L.] Univ Groningen, Theory Grp KVI, NL-9747 AA Groningen, Netherlands, Email: tolos@kvi.nl
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition (up)
ISSN 0556-2813 ISBN Medium
Area Expedition Conference
Notes ISI:000283648400011 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 335
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Author Bizzeti, P.G. et al; Gadea, A.
Title Transition probabilities in the X(5) candidate Ba-122 Type Journal Article
Year 2010 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 82 Issue 5 Pages 054311 - 10pp
Keywords
Abstract To investigate the possible X(5) character of Ba-122, suggested by the ground-state band energy pattern, the lifetimes of the lowest yrast states of Ba-122 have been measured, via the recoil distance Doppler-shift method. The relevant levels have been populated by using the Cd-108(O-16,2n)Ba-122 and the Sn-112(C-13, 3n)Ba-122 reactions. The B(E2) values deduced in the present work are compared to the predictions of the X(5) model and to calculations performed in the framework of the IBA-1 and IBA-2 models.
Address [Bizzeti, P. G.; Bizzeti-Sona, A. M.; Giannatiempo, A.; Melon, B.; Perego, A.; Sona, P.] Univ Firenze, Dipartimento Fis & Astron, IT-50019 Florence, Italy
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition (up)
ISSN 0556-2813 ISBN Medium
Area Expedition Conference
Notes ISI:000284205900004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 336
Permanent link to this record