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Author Acena, A.; Anabalon, A.; Astefanesei, D.; Mann, R. pdf  doi
openurl 
  Title Hairy planar black holes in higher dimensions Type Journal Article
  Year 2014 Publication Journal Of High Energy Physics Abbreviated Journal J. High Energy Phys.  
  Volume Issue 1 Pages 21 pp  
  Keywords Classical Theories of Gravity; Black Holes  
  Abstract We construct exact hairy planar black holes in D-dimensional AdS gravity. These solutions are regular except at the singularity and have stress-energy that satisfies the null energy condition. We present a detailed analysis of their thermodynamical properties and show that the first law is satisfied. We also discuss these solutions in the context of AdS/CFT duality and construct the associated c-function.  
  Address [Acena, Andres] Univ Nacl Cuyo, Inst Ciencias Basicas, RA-5500 Mendoza, Argentina, Email: acena.andres@gmail.com;  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1029-8479 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000346240600002 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 431  
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Author Acuna, V.; Ferreira, C.E.; Freire, A.S.; Moreno, E. pdf  doi
openurl 
  Title Solving the maximum edge biclique packing problem on unbalanced bipartite graphs Type Journal Article
  Year 2014 Publication Discrete Applied Mathematics Abbreviated Journal Discret Appl. Math.  
  Volume 164 Issue Pages 2-12  
  Keywords Maximum edge biclique packing; Branch-and-price; Metabolic networks; Product bundling  
  Abstract A biclique is a complete bipartite graph. Given an (L, R)-bipartite graph G = (V, E) and a positive integer k, the maximum edge biclique packing (num') problem consists in finding a set of at most k bicliques, subgraphs of G, such that the bicliques are vertex disjoint with respect to a subset of vertices S, where S E {V, L, R}, and the number of edges inside the bicliques is maximized. The maximum edge biclique (mEs) problem is a special case of the MEBP problem in which k = 1. Several applications of the MEB problem have been studied and, in this paper, we describe applications of the MEBP problem in metabolic networks and product bundling. In these applications the input graphs are very unbalanced (i.e., IRI is considerably greater than ILI), thus we consider carefully this property in our models. We introduce a new formulation for the MEB problem and a branch-and-price scheme, using the classical branch rule by Ryan and Foster, for the MEBP problem. Finally, we present computational experiments with instances that come from the described applications and also with randomly generated instances. (C) 2011 Elsevier B.V. All rights reserved.  
  Address [Acuna, V.] Univ Lyon 1, F-69622 Villeurbanne, France, Email: afreire@ime.usp.br  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0166-218x ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000332427400002 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 361  
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Author Aiyangar, A.K.; Vivanco, J.; Au, A.G.; Anderson, P.A.; Smith, E.L.; Ploeg, H.L. pdf  doi
openurl 
  Title Dependence of Anisotropy of Human Lumbar Vertebral Trabecular Bone on Quantitative Computed Tomography-Based Apparent Density Type Journal Article
  Year 2014 Publication Journal Of Biomechanical Engineering-Transactions Of The Asme Abbreviated Journal J. Biomech. Eng.-Trans. ASME  
  Volume 136 Issue 9 Pages 10 pp  
  Keywords human lumbar vertebrae; trabecular bone; anisotropic ratio; transverse isotropy; elastic modulus-density relationship; strain-density relationship  
  Abstract Most studies investigating human lumbar vertebral trabecular bone (HVTB) mechanical property-density relationships have presented results for the superior-inferior (SI), or “ on-axis” direction. Equivalent, directly measured data from mechanical testing in the transverse (TR) direction are sparse and quantitative computed tomography (QCT) density-dependent variations in the anisotropy ratio of HVTB have not been adequately studied. The current study aimed to investigate the dependence of HVTB mechanical anisotropy ratio on QCT density by quantifying the empirical relationships between QCT-based apparent density of HVTB and its apparent compressive mechanical propertieselastic modulus (E-app), yield strength (sigma(y)), and yield strain (epsilon(y))-in the SI and TR directions for future clinical QCT-based continuum finite element modeling of HVTB. A total of 51 cylindrical cores (33 axial and 18 transverse) were extracted from four L1 human lumbar cadaveric vertebrae. Intact vertebrae were scanned in a clinical resolution computed tomography (CT) scanner prior to specimen extraction to obtain QCT density, rho(CT). Additionally, physically measured apparent density, computed as ash weight over wet, bulk volume, rho(app), showed significant correlation with rho(CT) [rho(CT) = 1.0568 x rho(app), r = 0.86]. Specimens were compression tested at room temperature using the Zetos bone loading and bioreactor system. Apparent elastic modulus (E-app) and yield strength (sigma(y)) were linearly related to the rho(CT) in the axial direction [E-SI = 1493.8 x (rho(CT)), r = 0.77, p < 0.01; sigma(Y,SI) = 6.9 x (rho(CT)) = 0.13, r = 0.76, p < 0.01] while a power-law relation provided the best fit in the transverse direction [E-TR 3349.1 x (rho(CT))(1.94), r = 0.89, p < 0.01; sigma(Y,TR) 18.81 x (rho(CT)) 1.83, r = 0.83, p < 0.01]. No significant correlation was found between epsilon(y) and rho(CT) in either direction. E-app and sigma(y) in the axial direction were larger compared to the transverse direction by a factor of 3.2 and 2.3, respectively, on average. Furthermore, the degree of anisotropy decreased with increasing density. Comparatively, epsilon(y) exhibited only a mild, but statistically significant anisotropy: transverse strains were larger than those in the axial direction by 30%, on average. Ability to map apparent mechanical properties in the transverse direction, in addition to the axial direction, from CT-based densitometric measures allows incorporation of transverse properties in finite element models based on clinical CT data, partially offsetting the inability of continuum models to accurately represent trabecular architectural variations.  
  Address [Aiyangar, Ameet K.] EMPA Swiss Fed Labs Mat Sci & Technol Dubendorf, Lab Mech Syst Engn 304, CH-8600 Dubendorf, Switzerland, Email: ameetaiyangar@gmail.com  
  Corporate Author Thesis  
  Publisher Asme Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0148-0731 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000340617700003 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 401  
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Author Anabalon, A.; Astefanesei, D. pdf  doi
openurl 
  Title Black holes in omega-deformed gauged N=8 supergravity Type Journal Article
  Year 2014 Publication Physics Letters B Abbreviated Journal Phys. Lett. B  
  Volume 732 Issue Pages 137-141  
  Keywords  
  Abstract Motivated by the recently found 4-dimensional omega-deformed gauged supergravity, we investigate the black hole solutions within the single scalar field consistent truncations of this theory. We construct black hole solutions that have spherical, toroidal, and hyperbolic horizon topologies. The scalar field is regular everywhere outside the curvature singularity and the stress-energy tensor satisfies the null energy condition. When the parameter CO does not vanish, there is a degeneracy in the spectrum of black hole solutions for boundary conditions that preserve the asymptotic Anti-de Sitter symmetries. These boundary conditions correspond to multi-trace deformations in the dual field theory. (C) 2014 The Authors. Published by Elsevier B.V.  
  Address [Anabalon, Andres] Univ Adolfo Ibanez, Fac Artes Liberales, Dept Ciencias, Vina Del Mar, Chile, Email: andres.anabalon@uai.cl;  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-2693 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000335307900023 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 375  
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Author Anabalon, A.; Bicak, J.; Saavedra, J. pdf  doi
openurl 
  Title Hairy black holes: Stability under odd-parity perturbations and existence of slowly rotating solutions Type Journal Article
  Year 2014 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 90 Issue 12 Pages 6 pp  
  Keywords  
  Abstract We show that, independently of the scalar field potential and of specific asymptotic properties of the spacetime (asymptotically flat, de Sitter or anti-de Sitter), any static, spherically symmetric or planar, black hole solution of the Einstein theory minimally coupled to a real scalar field with a general potential is mode stable under linear odd-parity perturbations. To this end, we generalize the Regge-Wheeler equation for a generic self-interacting scalar field, and show that the potential of the relevant Schrodinger operator can be mapped, by the so-called S-deformation, to a semipositively defined potential. With these results at hand we study the existence of slowly rotating configurations. The frame dragging effect is compared with the corresponding effect in the case of a Kerr black hole.  
  Address [Anabalon, Andres] Univ Adolfo Ibanez, Fac Artes Liber, Dept Ciencias, Vina Del Mar, Chile, Email: andres.anabalon@uai.cl;  
  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  
  ISSN 1550-7998 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000349414800003 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 450  
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Author Anabalon, A.; Cisterna, A.; Oliva, J. pdf  doi
openurl 
  Title Asymptotically locally AdS and flat black holes in Horndeski theory Type Journal Article
  Year 2014 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 89 Issue 8 Pages 9 pp  
  Keywords  
  Abstract In this paper we construct asymptotically locally AdS and flat black holes in the presence of a scalar field whose kinetic term is constructed out from a linear combination of the metric and the Einstein tensor. The field equations as well as the energy-momentum tensor are second order in the metric and the field, therefore the theory belongs to the ones defined by Horndeski. We show that in the presence of a cosmological term in the action, it is possible to have a real scalar field in the region outside the event horizon. The solutions are characterized by a single integration constant, the scalar field vanishes at the horizon and it contributes to the effective cosmological constant at infinity. We extend these results to the topological case. The solution is disconnected from the maximally symmetric AdS background, however, within this family there exists a gravitational soliton which is everywhere regular. This soliton is therefore used as a background to define a finite Euclidean action and to obtain the thermodynamics of the black holes. For a certain region in the space of parameters, the thermodynamic analysis reveals a critical temperature at which a Hawking-Page phase transition between the black hole and the soliton occurs. We extend the solution to arbitrary dimensions greater than 4 and show that the presence of a cosmological term in the action allows one to consider the case in which the standard kinetic term for the scalar it is not present. In such a scenario, the solution reduces to an asymptotically flat black hole.  
  Address [Anabalon, Andres] Univ Adolfo Ibanez, Fac Artes Liber, Dept Ciencias, Vina Del Mar, Chile, Email: andres.anabalon@uai.cl;  
  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  
  ISSN 1550-7998 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000334336100005 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 371  
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Author Barrera, J.; Ycart, B. pdf  url
openurl 
  Title Bounds for left and right window cutoffs Type Journal Article
  Year 2014 Publication Alea-Latin American Journal Of Probability And Mathematical Statistics Abbreviated Journal ALEA-Latin Am. J. Probab. Math. Stat.  
  Volume 11 Issue 2 Pages 445-458  
  Keywords cutoff; exponential ergodicity  
  Abstract The location and width of the time window in which a sequence of processes converges to equilibrum are given under conditions of exponential convergence. The location depends on the side: the left-window and right-window cutoffs may have different locations. Bounds on the distance to equilibrium are given for both sides. Examples prove that the bounds are tight.  
  Address [Barrera, Javiera] Univ Adolfo Ibanez, Fac Ingn & Ciencias, Santiago, Chile, Email: javiera.barrera@uai.cl;  
  Corporate Author Thesis  
  Publisher Impa Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1980-0436 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000209555300005 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 568  
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Author Barria, A.M.; Lardies, M.A.; Beckerman, A.P.; Bacigalupe, L.D. pdf  doi
openurl 
  Title Latitude or biogeographic breaks? Determinants of phenotypic (co)variation in fitness-related traits in Betaeus truncatus along the Chilean coast Type Journal Article
  Year 2014 Publication Marine Biology Abbreviated Journal Mar. Biol.  
  Volume 161 Issue 1 Pages 111-118  
  Keywords  
  Abstract Ectothermal organisms distributed along environmental gradients in a wide geographical distribution display extensive phenotypic variation. This is particularly pervasive along latitudinal clines, which are linked to gradual changes in environmental factors. Widespread species may also be distributed among biogeographic breaks, which in contrast to smooth clines, often show abrupt changes in phenotypic traits. In species with widespread latitudinal distribution that also encompass important biogeographical breaks, it is not clear which of those factors prevails on shaping the phenotypic variation or if some traits are particularly more sensitive to one or the other. To evaluate this, we measured 4 fitness-related traits in 6 populations of the intertidal snapping shrimp Betaeus truncatus, as its distribution along Chile expands over 40A degrees in latitude and three major biogeographical provinces. Here, we statistically evaluated the role of both, latitude and biogeographic breaks, on mean population values of fitness-related traits but also on the variances and covariances (i.e., P-matrix) between them. Overall, our results (1) indicate that latitude is more important than breaks in shaping the phenotypic variation of most of these fitness-related traits, (2) show that the differences in the variance-covariance relationship among traits between the extremes of the gradient arises from gradual increases in variance and rather sharp changes in covariance at mid-latitudes and (3) show that at present, it is difficult to unambiguously determine whether natural selection or plasticity is responsible for the observed pattern in means, variances and covariances and only further work might disentangle these possibilities.  
  Address [Barria, Aura M.; Beckerman, Andrew P.; Bacigalupe, Leonardo D.] Univ Austral Chile, Inst Ciencias Ambientales & Evolutivas, Fac Ciencias, Valdivia, Chile, Email: lbacigal@gmail.com  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0025-3162 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000329792700010 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 342  
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Author Berkovits, N.; Chandia, O. pdf  doi
openurl 
  Title Simplified pure spinor b ghost in a curved heterotic superstring background Type Journal Article
  Year 2014 Publication Journal Of High Energy Physics Abbreviated Journal J. High Energy Phys.  
  Volume Issue 6 Pages 12 pp  
  Keywords Superstrings and Heterotic Strings; Conformal Field Models in String Theory  
  Abstract Using the RNS-like fermionic vector variables introduced in arXiv:1305.0693, the pure spinor b ghost in a curved heterotic superstring background is easily constructed. This construction simplifies and completes the b ghost construction in a curved background of arXiv:1311.7012.  
  Address [Berkovits, Nathan] Univ Estadual Paulista, UNESP, Inst Fis Teor, ICTP South Amer Inst Fundamental Res, BR-01140070 Sao Paulo, Brazil, Email: nberkovi@ift.unesp.br;  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1029-8479 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000338964600001 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 392  
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Author Besson, S.; Dumais, J. pdf  doi
openurl 
  Title Stochasticity in the symmetric division of plant cells: when the exceptions are the rule Type Journal Article
  Year 2014 Publication Frontiers In Plant Science Abbreviated Journal Front. Plant Sci.  
  Volume 5 Issue Pages 4 pp  
  Keywords  
  Abstract  
  Address [Besson, Sebastien] Univ Dundee, Ctr Gene Regulat & Express, Coll Life Sci, Dundee, Scotland, Email: jacques.dumais@uai.cl  
  Corporate Author Thesis  
  Publisher Frontiers Research Foundation Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1664-462x ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000344740100002 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 456  
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Author Bitran, E.; Rivera, P.; Villena, M.J. pdf  doi
openurl 
  Title Water management problems in the Copiapo Basin, Chile: markets, severe scarcity and the regulator Type Journal Article
  Year 2014 Publication Water Policy Abbreviated Journal Water Policy  
  Volume 16 Issue 5 Pages 844-863  
  Keywords Aquifers; Economic incentives; Regulations; Sustainable water management; Water markets  
  Abstract This research focuses on the determination of the factors that led to the failure of water management in the Copiapo Basin in Chile. Interestingly, the existence of full private ownership and free tradability of water rights has not prevented the overexploitation of groundwater resources. In the paper, firstly, water regulation and the role of the regulator in Chile are briefly discussed. Secondly, the evolution of water resources in the Copiapo region is characterized and analyzed, and the granting of water use rights in the basin in the last 30 years is concisely described. Thirdly, we examine and analyze prices and quantities traded in the water market of the Copiapo region. We will argue that this crisis is a consequence first of failure in regulatory implementation and second of an extremely rigid regulatory framework that leaves limited room for adjustment to changing conditions, especially regarding the emergence of new information concerning water availability. We believe this investigation is not only relevant for this case in particular, but also for other regions and countries where water markets are in place.  
  Address [Bitran, Eduardo; Villena, Marcelo J.] Univ Adolfo Ibanez, Fac Engn & Sci, Santiago, Chile, Email: marcelo.villena@uai.cl  
  Corporate Author Thesis  
  Publisher Iwa Publishing Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1366-7017 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000349029200005 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 449  
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Author Braun, S.; Asenjo, F.A.; Mahajan, S.M. pdf  doi
openurl 
  Title Comment on “Spin-Gradient-Driven Light Amplification in a Quantum Plasma” Reply Type Journal Article
  Year 2014 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.  
  Volume 112 Issue 12 Pages 1 pp  
  Keywords  
  Abstract  
  Address [Braun, S.; Asenjo, F. A.; Mahajan, S. M.] Univ Texas AustinStudies, Inst Fus Studies, Austin, TX 78712 USA, Email: faz@physics.utexas.edu;  
  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  
  ISSN 0031-9007 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000333921000007 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 471  
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Author Canessa, E.; Chaigneau, S. pdf  doi
openurl 
  Title The dynamics of social agreement according to Conceptual Agreement Theory Type Journal Article
  Year 2014 Publication Quality & Quantity Abbreviated Journal Qual. Quant.  
  Volume 48 Issue 6 Pages 3289-3309  
  Keywords Conceptual Agreement Theory; Agent-based modeling; Conceptual diversity; Dynamics of conceptual development  
  Abstract Many social phenomena can be viewed as processes in which individuals in social groups develop agreement (e.g., public opinion, the spreading of rumor, the formation of social and linguistic conventions). Conceptual Agreement Theory (CAT) models social agreement as a simplified communicational event in which an Observer and Actor exchange ideas about a concept , and where uses that information to infer whether 's conceptual state is the same as its own (i.e., to infer agreement). Agreement may be true (when infers that is thinking and this is in fact the case, event ) or illusory (when infers that is thinking and this is not the case, event ). In CAT, concepts that afford or become more salient in the minds of members of social groups. Results from an agent-based model (ABM) and probabilistic model that implement CAT show that, as our conceptual analyses suggested would be the case, the simulated social system selects concepts according to their usefulness to agents in promoting agreement among them (Experiment 1). Furthermore, the ABM exhibits more complex dynamics where similar minded agents cluster and are able to retain useful concepts even when a different group of agents discards them (Experiment 2). We discuss the relevance of CAT and the current findings for analyzing different social communication events, and suggest ways in which CAT could be put to empirical test.  
  Address [Canessa, Enrique] Univ Adolfo Ibanez, Fac Ingn & Ciencias, Vina Del Mar, Chile, Email: ecanessa@uai.cl;  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0033-5177 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000343294900024 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 418  
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Author Canfora, F.; Gomez, A.; Sorella, S.P.; Vercauteren, D. pdf  doi
openurl 
  Title Study of Yang-Mills.-Chern-Simons theory in presence of the Gribov horizon Type Journal Article
  Year 2014 Publication Annals Of Physics Abbreviated Journal Ann. Phys.  
  Volume 345 Issue Pages 166-177  
  Keywords Topologically massive gauge theory; Gribov quantization; Gauge propagator  
  Abstract The two-point gauge correlation function in Yang-Mills-Chern-Simons theory in three dimensional Euclidean space is analysed by taking into account the non-perturbative effects of the Gribov horizon. In this way, we are able to describe the confinement and de-confinement regimes, which naturally depend on the topological mass and on the gauge coupling constant of the theory. (C) 2014 Elsevier Inc. All rights reserved.  
  Address [Canfora, Fabrizio] Ctr Estudios Cient, Valdivia, Chile, Email: canfora@cecs.cl;  
  Corporate Author Thesis  
  Publisher Academic Press Inc Elsevier Science Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-4916 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000335546400009 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 374  
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Author Chandia, O. pdf  doi
openurl 
  Title The non-minimal heterotic pure spinor string in a curved background Type Journal Article
  Year 2014 Publication Journal Of High Energy Physics Abbreviated Journal J. High Energy Phys.  
  Volume Issue 3 Pages 16 pp  
  Keywords Superstrings and Heterotic Strings; Conformal Field Models in String Theory; Topological Strings  
  Abstract We study the non-minimal pure spinor string in a curved background. We find that the minimal BRST invariance implies the existence of a non-trivial stress-energy tensor for the minimal and non-minimal variables in the heterotic curved background. We find constraint equations for the b ghost. We construct the b ghost as a solution of these constraints.  
  Address [Chandia, Osvaldo] Univ Adolfo Ibanez, Fac Artes Liberales, Santiago, Chile, Email: ochandiaq@gmail.com  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1029-8479 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000333802200001 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 364  
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Author Chandia, O.; Bevilaqua, L.I.; Vallilo, B.C. pdf  doi
openurl 
  Title AdS pure spinor superstring in constant backgrounds Type Journal Article
  Year 2014 Publication Journal Of High Energy Physics Abbreviated Journal J. High Energy Phys.  
  Volume Issue 6 Pages 16 pp  
  Keywords Superstrings and Heterotic Strings; Conformal Field Models in String Theory; BRST Symmetry  
  Abstract In this paper we study the pure spinor formulation of the superstring in AdS(5) x S-5 around point particle solutions of the classical equations of motion. As a particular example we quantize the pure spinor string in the BMN background.  
  Address [Chandia, Osvaldo] Univ Adolfo Ibanez, Fac Artes Liberales, Fac Ingn & Ciencias, Dept Ciencias, Santiago, Chile, Email: ochandiaq@gmail.com;  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1029-8479 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000347856200001 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 437  
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Author Chuaqui, M.; Hamada, H.; Hernandez, R.; Kohr, G. pdf  doi
openurl 
  Title Pluriharmonic mappings and linearly connected domains in C-n Type Journal Article
  Year 2014 Publication Israel Journal Of Mathematics Abbreviated Journal Isr. J. Math.  
  Volume 200 Issue 1 Pages 489-506  
  Keywords  
  Abstract In this paper we obtain certain sufficient conditions for the univalence of pluriharmonic mappings defined in the unit ball of C-n . The results are generalizations of conditions of Chuaqui and Hernandez that relate the univalence of planar harmonic mappings with linearly connected domains, and show how such domains can play a role in questions regarding injectivity in higher dimensions. In addition, we extend recent work of Hernandez and Martin on a shear type construction for planar harmonic mappings, by adapting the concept of stable univalence to pluriharmonic mappings of the unit ball into C-n .  
  Address [Chuaqui, Martin] Pontificia Univ Catolica Chile, Fac Matemat, Santiago 22, Chile, Email: mchuaqui@mat.puc.cl;  
  Corporate Author Thesis  
  Publisher Hebrew Univ Magnes Press Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-2172 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000338204700022 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 389  
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Author Comisso, L.; Asenjo, F.A. pdf  doi
openurl 
  Title Thermal-Inertial Effects on Magnetic Reconnection in Relativistic Pair Plasmas Type Journal Article
  Year 2014 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.  
  Volume 113 Issue 4 Pages 5 pp  
  Keywords  
  Abstract The magnetic reconnection process is studied in relativistic pair plasmas when the thermal and inertial properties of the magnetohydrodynamical fluid are included. We find that in both Sweet-Parker and Petschek relativistic scenarios there is an increase of the reconnection rate owing to the thermal-inertial effects, both satisfying causality. To characterize the new effects we define a thermal-inertial number which is independent of the relativistic Lundquist number, implying that reconnection can be achieved even for vanishing resistivity as a result of only thermal-inertial effects. The current model has fundamental importance for relativistic collisionless reconnection, as it constitutes the simplest way to get reconnection rates faster than those accessible with the sole resistivity.  
  Address [Comisso, Luca] Politecn Torino, Dipartimento Energia, I-10129 Turin, Italy, Email: luca.comisso@polito.it;  
  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  
  ISSN 0031-9007 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000339620300007 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 393  
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Author Contreras, G.M. pdf  doi
openurl 
  Title Stochastic volatility models at rho = +/- 1 as second class constrained Hamiltonian systems Type Journal Article
  Year 2014 Publication Physica A-Statistical Mechanics And Its Applications Abbreviated Journal Physica A  
  Volume 405 Issue Pages 289-302  
  Keywords Fokker-Planck equation; Stochastic volatility models; Option pricing; Singular Lagrangian systems; Dirac's method; Constrained Hamiltonian path integrals  
  Abstract The stochastic volatility models used in the financial world are characterized, in the continuous-time case, by a set of two coupled stochastic differential equations for the underlying asset price S and volatility sigma. In addition, the correlations of the two Brownian movements that drive the stochastic dynamics are measured by the correlation parameter rho (-1 <= rho <= 1). This stochastic system is equivalent to the Fokker-Planck equation for the transition probability density of the random variables S and sigma. Solutions for the transition probability density of the Heston stochastic volatility model (Heston, 1993) were explored in Dragulescu and Yakovenko (2002), where the fundamental quantities such as the transition density itself, depend on rho in such a manner that these are divergent for the extreme limit rho = +/- 1. The same divergent behavior appears in Hagan et al. (2002), where the probability density of the SABR model was analyzed. In an option pricing context, the propagator of the bi-dimensional Black-Scholes equation was obtained in Lemmens et al. (2008) in terms of the path integrals, and in this case, the propagator diverges again for the extreme values rho = +/- 1. This paper shows that these similar divergent behaviors are due to a universal property of the stochastic volatility models in the continuum: all of them are second class constrained systems for the most extreme correlated limit rho = +/- 1. In this way, the stochastic dynamics of the rho = +/- 1 cases are different of the rho (1 <= rho <= 1) case, and it cannot be obtained as a continuous limit from the rho not equal +/- 1 regimen. This conclusion is achieved by considering the Fokker-Planck equation or the bi-dimensional Black-Scholes equation as a Euclidean quantum Schrodinger equation. Then, the analysis of the underlying classical mechanics of the quantum model, implies that stochastic volatility models at rho = +/- 1 correspond to a constrained system. To study the dynamics in an appropriate form, Dirac's method for constrained systems (Dirac, 1958, 1967) must be employed, and Dirac's analysis reveals that the constraints are second class. In order to obtain the transition probability density or the option price correctly, one must evaluate the propagator as a constrained Hamiltonian path-integral (Henneaux and Teitelboim, 1992), in a similar way to the high energy gauge theory models. In fact, for all stochastic volatility models, after integrating over momentum variables, one obtains an effective Euclidean Lagrangian path integral over the volatility alone. The role of the second class constraints is determining the underlying asset price S completely in terms of volatility, so it plays no role in the path integral. In order to examine the effect of the constraints on the dynamics for both extreme limits, the probability density function is evaluated by using semi-classical arguments, in an analogous manner to that developed in Hagan et al. (2002), for the SABR model. (C) 2014 Elsevier B.V. All rights reserved.  
  Address Univ Adolfo Ibanez, Fac Ingn & Ciencias, Santiago, Chile, Email: mauricio.contreras@uai.cl  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0378-4371 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000337854200030 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 382  
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Author Contreras, M.; Hojman, S.A. pdf  doi
openurl 
  Title Option pricing, stochastic volatility, singular dynamics and constrained path integrals Type Journal Article
  Year 2014 Publication Physica A-Statistical Mechanics And Its Applications Abbreviated Journal Physica A  
  Volume 393 Issue Pages 391-403  
  Keywords Option pricing; Stochastic volatility; Quantum mechanics; Singular Lagrangian systems; Dirac's method; Constrained Hamiltonian path integrals  
  Abstract Stochastic volatility models have been widely studied and used in the financial world. The Heston model (Heston, 1993) [7] is one of the best known models to deal with this issue. These stochastic volatility models are characterized by the fact that they explicitly depend on a correlation parameter p which relates the two Brownian motions that drive the stochastic dynamics associated to the volatility and the underlying asset. Solutions to the Heston model in the context of option pricing, using a path integral approach, are found in Lemmens et al. (2008) [21] while in Baaquie (2007,1997) [12,13] propagators for different stochastic volatility models are constructed. In all previous cases, the propagator is not defined for extreme cases rho = +/- 1. It is therefore necessary to obtain a solution for these extreme cases and also to understand the origin of the divergence of the propagator. In this paper we study in detail a general class of stochastic volatility models for extreme values rho = +/- 1 and show that in these two cases, the associated classical dynamics corresponds to a system with second class constraints, which must be dealt with using Dirac's method for constrained systems (Dirac, 1958,1967) [22,23] in order to properly obtain the propagator in the form of a Euclidean Hamiltonian path integral (Henneaux and Teitelboim, 1992) [25]. After integrating over momenta, one gets an Euclidean Lagrangian path integral without constraints, which in the case of the Heston model corresponds to a path integral of a repulsive radial harmonic oscillator. In all the cases studied, the price of the underlying asset is completely determined by one of the second class constraints in terms of volatility and plays no active role in the path integral. (C) 2013 Elsevier B.V. All rights reserved.  
  Address [Contreras, Mauricio] Univ Adolfo Ibanez, Fac Ingn & Ciencias, Santiago, Chile, Email: mauricio.contreras@uai.cl  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0378-4371 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000328179200034 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 335  
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