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Automatic brain tissue segmentation in fetal MRI using convolutional neural networksJun 11 2019MR images of fetuses allow clinicians to detect brain abnormalities in an early stage of development. The cornerstone of volumetric and morphologic analysis in fetal MRI is segmentation of the fetal brain into different tissue classes. Manual segmentation ... More

Automatic segmentation of the intracranialvolume in fetal MR imagesJul 31 2017MR images of the fetus allow non-invasive analysis of the fetal brain. Quantitative analysis of fetal brain development requires automatic brain tissue segmentation that is typically preceded by segmentation of the intracranial volume (ICV). This is challenging ... More

Flat rank 2 vector bundles on genus 2 curvesJan 10 2014Jul 27 2015We study the moduli space of trace-free irreducible rank 2 holomorphic connections over a complex projective curve of genus 2 and the forgetful map towards the moduli space of underlying vector bundles (including unstable bundles), for which we compute ... More

QIS-XML: An Extensible Markup Language for Quantum Information ScienceJun 14 2011This Master thesis examines issues of interoperability and integration between the Classic Information Science (CIS) and Quantum Information Science (QIS). It provides a short introduction to the Extensible Markup Language (XML) and proceeds to describe ... More

On the logarithmic connections over curvesMay 11 2012We study two different actions on the moduli spaces of logarithmic connections over smooth complex projective curves. Firstly, we establish a dictionary between logarithmic orbifold connections and parabolic logarithmic connections over the quotient curve. ... More

Non-flat extension of flat vector bundlesSep 10 2014Oct 29 2015We construct a pair (E ,F), where E is a holomorphic vector bundle over a compact Riemann surface and F a holomorphic subbundle of E, such that both F and E/F admit holomorphic connections, but E does not.

Hitchin Hamiltonians in genus 2Jun 08 2015We give an explicit expression of the Hitchin Hamiltonian system for rank two vector bundles with trivial determinant bundle over a curve of genus two.

Algebraic isomonodromic deformations and the mapping class groupDec 17 2016Feb 18 2018The germ of the universal isomonodromic deformation of a logarithmic connection on a stable n-pointed genus g-curve always exists in the analytic category. The first part of this paper investigates under which conditions it is the analytic germification ... More

Isomonodromic deformations of irregular connections and stability of bundlesAug 02 2016Let $G$ be a reductive affine algebraic group defined over $\mathbb C$, and let $\nabla_0$ be a meromorphic $G$-connection on a holomorphic $G$-bundle $E_0$, over a smooth complex curve $X_0$, with polar locus $P_0 \subset X_0$. We assume that $\nabla_0$ ... More

Isomonodromic deformations and very stable vector bundles of rank twoMar 21 2017For the universal isomonodromic deformation of an irreducible logarithmic rank two connection over a smooth complex projective curve of genus at least two, consider the family of holomorphic vector bundles over curves underlying this universal deformation. ... More

Isomonodromic deformations of logarithmic connections and stabilityMay 20 2015Oct 18 2015Let X_0 be a compact connected Riemann surface of genus g with D_0\subset X_0 an ordered subset of cardinality n, and let E_G be a holomorphic principal G-bundle on X_0, where G is a complex reductive affine algebraic group, that admits a logarithmic ... More

Isomonodromic deformations of logarithmic connections and stable parabolic vector bundlesJul 30 2018We consider irreducible logarithmic connections $(E,\,\delta)$ over compact Riemann surfaces $X$ of genus at least two. The underlying vector bundle $E$ inherits a natural parabolic structure over the singular locus of the connection $\delta$; the parabolic ... More

Isomonodromic deformations of logarithmic connections and stable parabolic vector bundlesJul 30 2018Apr 01 2019We consider irreducible logarithmic connections $(E,\,\delta)$ over compact Riemann surfaces $X$ of genus at least two. The underlying vector bundle $E$ inherits a natural parabolic structure over the singular locus of the connection $\delta$; the parabolic ... More

The Riemann-Hilbert mapping for $\mathfrak{sl}_2$ -systems over genus two curvesFeb 06 2016Nov 30 2018We prove in two different ways that the monodromy map from the space of irreducible $\mathfrak{sl}_2$-differential-systems on genus two Riemann surfaces, towards the character variety of $\mathrm{SL}_2$-representations of the fundamental group, is a local ... More

The Riemann-Hilbert mapping for $\mathfrak{sl}_2$ -systems over genus two curvesFeb 06 2016Nov 21 2016We prove in two different ways that the monodromy map from the space of irreducible $\mathfrak{sl}_2$-differential-systems on genus two Riemann surfaces, towards the character variety of $\mathrm{SL}_2$-representations of the fundamental group, is a local ... More

The Riemann-Hilbert mapping for $\mathfrak{sl}_2$ -systems over genus two curvesFeb 06 2016We prove in two different ways that the monodromy map from the space of irreducible $\mathfrak{sl}_2$-differential-systems on genus two Riemann surfaces, towards the character variety of $\mathrm{SL}_2$-representations of the fundamental group, is a local ... More

Quantum back action cancellation in the audio bandDec 25 2018We report on the cancellation of quantum back action noise in an optomechanical cavity. We perform two measurements of the displacement of the microresonator, one in reflection of the cavity, and one in transmission of the cavity. We show that measuring ... More

The global structure of galactic discsApr 30 1998A statistical study of global galaxy parameters can help to improve our understanding of galaxy formation processes. In this paper we present the analysis of global galaxy parameters based on optical and near-infrared observations of a large sample of ... More

Flexible Widely-Linear Multi-Branch Decision Feedback Detection Algorithms for Massive MIMO SystemsDec 19 2015This paper presents widely-linear multi-branch decision feedback detection techniques for large-scale multiuser multiple-antenna systems. We consider a scenario with impairments in the radio-frequency chain in which the in-phase (I) and quadrature (Q) ... More

Matrix model formulation of four dimensional gravityNov 06 2000The attempt of extending to higher dimensions the matrix model formulation of two-dimensional quantum gravity leads to the consideration of higher rank tensor models. We discuss how these models relate to four dimensional quantum gravity and the precise ... More

Generalized Ladder Operators for the Dirac-Coulomb Problem via SUSY QMNov 11 2003May 17 2004The supersymmetry in quantum mechanics and shape invariance condition are applied as an algebraic method to solve the Dirac-Coulomb problem. The ground state and the excited states are investigated using new generalized ladder operators.

Adaptive and Iterative Multi-Branch MMSE Decision Feedback Detection Algorithms for MIMO SystemsAug 13 2013In this work, decision feedback (DF) detection algorithms based on multiple processing branches for multi-input multi-output (MIMO) spatial multiplexing systems are proposed. The proposed detector employs multiple cancellation branches with receive filters ... More

Generalized Reduced-Rank Decompositions Using Switching and Adaptive Algorithms for Space-Time Adaptive ProcessingApr 06 2013This work presents generalized low-rank signal decompositions with the aid of switching techniques and adaptive algorithms, which do not require eigen-decompositions, for space-time adaptive processing. A generalized scheme is proposed to compute low-rank ... More

Quantum singular operator limits of thin Dirichlet tubes via $Γ$-convergenceOct 11 2010The $\Gamma$-convergence of lower bounded quadratic forms is used to study the singular operator limit of thin tubes (i.e., the vanishing of the cross section diameter) of the Laplace operator with Dirichlet boundary conditions; a procedure to obtain ... More

Early stages of ramified growth in quasi-two-dimensional electrochemical depositionDec 22 1995I have measured the early stages of the growth of branched metal aggregates formed by electrochemical deposition in very thin layers. The growth rate of spatial Fourier modes is described qualitatively by the results of a linear stability analysis [D.P. ... More

The K-band luminosity functions of cluster galaxiesNov 15 2016Nov 16 2016We derive the galaxy luminosity function in the $K_s$ band for galaxies in 24 clusters to provide a local reference for higher redshift studies and to analyse how and if the luminosity function varies according to environment and cluster properties. We ... More

Study of Distributed Spectrum Estimation Using Alternating Mixed Discrete-Continuous AdaptationApr 11 2016This paper proposes a distributed alternating mixed discrete-continuous (DAMDC) algorithm to approach the oracle algorithm based on the diffusion strategy for parameter and spectrum estimation over sensor networks. A least mean squares (LMS) type algorithm ... More

Study of Distributed Conjugate Gradient Strategies for Distributed Estimation Over Sensor NetworksJan 16 2016This paper presents distributed conjugate gradient algorithms for distributed parameter estimation and spectrum estimation over wireless sensor networks. In particular, distributed conventional conjugate gradient (CCG) and modified conjugate gradient ... More

On the Dirac OscillatorJul 08 2007Dec 18 2007In the present work we obtain a new representation for the Dirac oscillator based on the Clifford algebra $C\ell_7.$ The symmetry breaking and the energy eigenvalues for our model of the Dirac oscillator are studied in the non-relativistic limit.

The K-band luminosity functions of cluster galaxiesNov 15 2016We derive the galaxy luminosity function in the $K_s$ band for galaxies in 24 clusters to provide a local reference for higher redshift studies and to analyse how and if the luminosity function varies according to environment and cluster properties. We ... More

Canonical ``Loop'' Quantum Gravity and Spin Foam ModelsMar 19 1999Apr 26 1999The canonical ``loop'' formulation of quantum gravity is a mathematically well defined, background independent, non perturbative standard quantization of Einstein's theory of General Relativity. Some among the most meaningful results of the theory are: ... More

The $q$-Deformed Wigner Oscillator in Quantum MechanicsAug 28 2003Using a super-realization of the Wigner-Heisenberg algebra a new realization of the q-deformed Wigner oscillator is implemented.

The Quantum Mechanics SUSY Algebra: An Introductory ReviewMay 02 2002Sep 12 2002Starting with the Lagrangian formalism with N=2 supersymmetry in terms of two Grassmann variables in Classical Mechanics, the Dirac canonical quantization method is implemented. The N=2 supersymmetry algebra is associated to one-component and two-component ... More

Report on Two-Step Knowledge-Aided Iterative ESPRIT AlgorithmMar 21 2017In this work, we propose a subspace-based algorithm for direction-of-arrival (DOA) estimation, referred to as two-step knowledge-aided iterative estimation of signal parameters via rotational invariance techniques (ESPRIT) method (Two-Step KAI-ESPRIT), ... More

Robust Low-Rank LCMV Beamforming Algorithms Based on Joint Iterative Optimization StrategiesFeb 10 2013This chapter presents reduced-rank linearly constrained minimum variance (LCMV) algorithms based on the concept of joint iterative optimization of parameters. The proposed reduced-rank scheme is based on a constrained robust joint iterative optimization ... More

Massive MIMO Systems: Signal Processing Challenges and Research TrendsOct 28 2013This article presents a tutorial on multiuser multiple-antenna wireless systems with a very large number of antennas, known as massive multi-input multi-output (MIMO) systems. Signal processing challenges and future trends in the area of massive MIMO ... More

Extended 2d generalized dilaton gravity theoriesMay 06 2006Aug 06 2008We show that an anomaly-free description of matter in (1+1) dimensions requires a deformation of the 2d relativity principle, which introduces a non-trivial center in the 2d Poincare algebra. Then we work out the reduced phase-space of the anomaly-free ... More

Modeling Epidermis Homeostasis and Psoriasis PathogenesisDec 05 2013Dec 23 2014We present a computational model to study the spatiotemporal dynamics of the epidermis homeostasis under normal and pathological conditions. The model consists of a population kinetics model of the central transition pathway of keratinocyte proliferation, ... More

Network theory approach for data evaluation in the dynamic force spectroscopy of biomolecular interactionsNov 12 2009Investigations of molecular bonds between single molecules and molecular complexes by the dynamic force spectroscopy are subject to large fluctuations at nanoscale and possible other aspecific binding, which mask the experimental output. Big efforts are ... More

On the Hydrogen Atom via Wigner-Heisenberg AlgebraDec 03 2008Aug 18 2009We extend the usual Kustaanheimo-Stiefel $4D\to 3D$ mapping to study and discuss a constrained super-Wigner oscillator in four dimensions. We show that the physical hydrogen atom is the system that emerges in the bosonic sector of the mapped super 3D ... More

Monogamy Inequality and Residual Entanglement of Three Qubits under DecoherenceFeb 27 2009Aug 28 2009Exploring an analytical expression for the convex roof of the pure state squared concurrence for rank 2 mixed states the entanglement of a system of three particles under decoherence is studied, using the monogamy inequality for mixed states and the residual ... More

Quantum Correlations in Multipartite Quantum SystemsJun 09 2017We review some concepts and properties of quantum correlations, in particular multipartite measures, geometric measures and monogamy relations. We also discuss the relation between classical and total correlations

Knowledge-Aided Normalized Iterative Hard Thresholding Algorithms and Applications to Sparse ReconstructionSep 25 2018This paper deals with the problem of sparse recovery often found in compressive sensing applications exploiting a priori knowledge. In particular, we present a knowledge-aided normalized iterative hard thresholding (KA-NIHT) algorithm that exploits information ... More

Target Fragmentation and Fracture FunctionsOct 01 1997We analyse recent data on the production of forward neutrons in deep inelastic scattering at HERA in the framework of a perturbative QCD description for semi-inclusive processes, which includes fracture functions.

Vacuum polarization by topological defects in de Sitter spacetimeFeb 23 2010In this paper we investigate the vacuum polarization effects associated with a massive quantum scalar field in de Sitter spacetime in the presence of gravitational topological defects. Specifically we calculate the vacuum expectation value of the field ... More

Comment to "Fine structure constant in the spacetime of a cosmic string"Jul 07 2005In the paper Phys. Lett. B614 (2005), 140-142, F. Nasseri shows that the values of the fine structure constant reduces due to the presence of a cosmic string. In this comment I want to point out that this conclusion is not completely correct in the sense ... More

Effects of Anomalous Magnetic Moment in the Quantum Motion of Neutral Particle in Magnetic and Electric Fields Produced by a Linear Source in a Conical SpacetimeMar 01 2004Jun 09 2004In this paper we analyse the effect of the anomalous magnetic moment on the non-relativistic quantum motion of a neutral particle in magnetic and electric fields produced by linear sources of constant current and charge density, respectively.

Vacuum Polarization Effects in the Global Monopole Spacetime in the Presence of Wu-Yang Magnetic MonopoleJul 05 2002In this paper we consider the presence of the Wu-Yang magnetic monopole in the global monopole spacetime and their influence on the vacuum polarization effects around these two monopoles placed together. According to Wu-Yang [Nucl. Phys. {\bf B107}, 365 ... More

N-representability and density-functional construction in curvilinear coordinatesDec 15 1997In practical implementations of density-functional theory, the only term where an orbital description is needed is the kinetic one. Even this term in principle depends on the density only, but its explicit form is unknown. We provide a novel solution ... More

The Faint End of the Luminosity Function in Abell 426 and 539May 21 1998We derive $I$ band luminosity functions for galaxies in Abell 426 (Perseus and Abell 539, two rich, low galactic latitude clusters at moderate redshift. Cluster members are selected via the color-magnitude relation for bright galaxies. We find $\alpha=-1.56 ... More

Improved limits on photon velocity oscillationsMay 04 2002The mixing of the photon with a hypothetical sterile paraphotonic state would have consequences on the cosmological propagation of photons. The absence of distortions in the optical spectrum of distant Type Ia supernov\ae allows to extend by two orders ... More

Knizhnik-Zamolodchikov equation and extended symmetry for stable Hall statesMay 24 1995We describe a $n$ component abelian Hall fluid as a system of {\it composite bosons} moving in an average null field given by the external magnetic field and by the statistical flux tubes located at the position of the particles. The collective vacuum ... More

so(4) Plebanski Action and Relativistic Spin Foam ModelApr 26 1998Jun 30 1998In this note we study the correspondence between the ``relativistic spin foam'' model introduced by Barrett, Crane and Baez and the so(4) Plebanski action. We argue that the $so(4)$ Plebanski model is the continuum analog of the relativistic spin foam ... More

Vacuum polarization by a scalar field in de Sitter spacetime in the presence of global monopoleMay 11 2009Feb 09 2010In this paper we analyse the vacuum polarization effects associated with massive scalar quantum fields in a higher-dimensional de Sitter space in the presence of a global monopole. Because this analysis has been developed in a pure de Sitter space, here ... More

Euclidean Scalar Green Function in a Higher Dimensional Global SpacetimeSep 28 2001We construct the explicit Euclidean scalar Green function associated with a massless field in a higher dimensional global monopole spacetime, i.e., a $(1+d)$-spacetime with $d\geq3$ which presents a solid angle deficit. Our result is expressed in terms ... More

Fracture Functions for Diffractive and Leading Proton DISAug 11 1998We present a combined QCD analysis of diffractive and leading proton deep inelastic scattering data using the framework of fracture functions. It is shown that this framework allows a precise and unified perturbative QCD description for the data, alternative ... More

First Measurement of the Double Spin Asymmetry in $\vec{e}\vec{p}\to e' π^+ n$ in the Resonance RegionNov 23 2001Feb 07 2002The double spin asymmetry in the $\vec{e}\vec{p}\to e' \pi^+ n$ reaction has been measured for the first time in the resonance region for four-momentum transfer $Q^2=0.35-1.5$ GeV$^2$. Data were taken at Jefferson Lab with the CLAS detector using a 2.6 ... More

Effective low-energy theory of superconductivity in carbon nanotube ropesMay 13 2004We derive and analyze the low-energy theory of superconductivity in carbon nanotube ropes. A rope is modelled as an array of metallic nanotubes, taking into account phonon-mediated as well as Coulomb interactions, and arbitrary Cooper pair hopping amplitudes ... More

Induced self-interactions in the spacetime of a global monopole with finite coreApr 20 2012In this paper we analyze induced self-interactions for point-like particles with electric and scalar charges placed at rest in the spacetime of a global monopole admitting a general spherically symmetric inner structure to it. In order to develop this ... More

Wightman functions in de Sitter and anti-de Sitter spacetimes in the presence of cosmic stringApr 26 2012In this paper we evaluate the Wightman functions associated with a massive quantum scalar field in de Sitter and anti-de Sitter spacetimes in the presence of a cosmic string. Having these functions we calculate the corresponding renormalized vacuum expectation ... More

The Implicit Function Theorem when the matrix $\frac{\partial F}{\partial y}(x,y)$ is only continuous at the base pointDec 09 2013Aug 31 2015This article presents an elementary proof of the Implicit Function Theorem for differentiable maps F(x,y), defined on a finite-dimensional Euclidean space, with $\frac{\partial F}{\partial y}(x,y)$ only continuous at the base point. In the case of a single ... More

Kinematic segregation of nearby disk stars from the Hipparcos databaseApr 25 2007To better understand our Galaxy, we investigate the pertinency of describing the sys tem of nearby disk stars in terms of a two-components Schwarzschild velocity distributio n.Using the proper motion and parallax information of Hipparcos database, we ... More

The relation between velocity dispersions and chemical abundances in RAVE giantsSep 15 2017We developed a Bayesian framework to determine in a robust way the relation between velocity dispersions and chemical abundances in a sample of stars. Our modelling takes into account the uncertainties in the chemical and kinematic properties. We make ... More

Study of Polarization-Driven Shortening for Polar Codes Designed with the Gaussian ApproximationAug 01 2018This paper presents a polarization-driven (PD) shortening technique for the design of rate-compatible polar codes. The proposed shortening strategy consists of reducing the generator matrix by relating its row index with the channel polarization index. ... More

Inclusive and Semi-Inclusive Polarized DIS Data RevisitedJul 07 2000We perform a combined next to leading order analysis to both inclusive and semi-inclusive polarized deep inelastic scattering data, assessing the impact of new data in the extraction of the sea quark and gluon spin dependent densities. In particular, ... More

${\cal O}(α_{s})$ Spin-Dependent Weak Structure FunctionsDec 07 1994The complete next to leading logarithmic (${\cal O}(\alpha_{s})$) corrections to the spin dependent weak deep inelastic structure functions $g_{1},g_{3}$ and $g_{4}$, are calculated using dimensional regularization within the HVBM method. Analysing the ... More

Induced fermionic current densities by magnetic flux in higher dimensional cosmic string spacetimeJul 23 2009Mar 03 2010In this paper we analyse the vacuum fluctuations of quantum fermionic current densities, $<j^A(x)>$, induced by a magnetic flux running along the core of the conical space produced by the presence of cosmic string, in a $(1+d)-$dimensional bulk, for $2\leq ... More

Beam spin asymmetry in deep and exclusive pi0 electroproductionNov 29 2007Dec 04 2007The beam spin asymmetry (BSA) in the exclusive reaction ep->ep pi0 was measured with the CEBAF 5.77 GeV polarized electron beam and Large Acceptance Spectrometer(CLAS). The xB, Q2, t and phi dependences of the pi0 BSA are presented in the deep inelastic ... More

Rashba spin-orbit coupling and spin precession in carbon nanotubesJun 29 2005Sep 07 2005The Rashba spin-orbit coupling in carbon nanotubes and its effect on spin-dependent transport properties are analyzed theoretically. We focus on clean non-interacting nanotubes with tunable number of subbands $N$. The peculiar band structure is shown ... More

Acoustic phonon exchange, attractive interactions, and the Wentzel-Bardeen singularity in single-wall nanotubesDec 17 2002May 09 2003We derive the effective low-energy theory for interacting electrons in metallic single-wall carbon nanotubes taking into account acoustic phonon exchange within a continuum elastic description. In many cases, the nanotube can be described as a standard ... More

Two-electron bound states near a Coulomb impurity in gapped grapheneNov 16 2016Jan 23 2017We formulate and solve the perhaps simplest two-body bound state problem for interacting Dirac fermions in two spatial dimensions. A two-body bound state is predicted for gapped graphene monolayers in the presence of weakly repulsive electron-electron ... More

Blind Adaptive MIMO Receivers for CDMA Systems with Space-Time Block-Codes and Low-Cost AlgorithmsOct 21 2014In this paper we present low-complexity blind multi-input multi-output (MIMO) adaptive linear multiuser receivers for direct sequence code division multiple access (DS-CDMA) systems using multiple transmit antennas and space-time block codes (STBC) in ... More

Detection and Estimation Algorithms in Massive MIMO SystemsAug 21 2014This book chapter reviews signal detection and parameter estimation techniques for multiuser multiple-antenna wireless systems with a very large number of antennas, known as massive multi-input multi-output (MIMO) systems. We consider both centralized ... More

Low-Rank STAP Algorithm for Airborne Radar Based on Basis-Function ApproximationMar 20 2013In this paper, we develop a novel reduced-rank space-time adaptive processing (STAP) algorithm based on adaptive basis function approximation (ABFA) for airborne radar applications. The proposed algorithm employs the well-known framework of the side-lobe ... More

Near-Infrared Scanning Cavity Ringdown for Optical Loss Characterization of SupermirrorsMar 22 2019Apr 30 2019A cavity ringdown system for probing the spatial variation of optical loss across high-reflectivity mirrors is described. This system is employed to examine substrate-transferred crystalline supermirrors and quantify the effect of manufacturing process ... More

Near-Infrared Scanning Cavity Ringdown for Optical Loss Characterization of SupermirrorsMar 22 2019A cavity ringdown system for probing the spatial variation of optical loss across high-reflectivity mirrors is described. This system is employed to examine substrate-transferred crystalline supermirrors and quantify the effect of manufacturing process ... More

Gaia Data Release 1: Catalogue validationJan 01 2017Before the publication of the Gaia Catalogue, the contents of the first data release have undergone multiple dedicated validation tests. These tests aim at analysing in-depth the Catalogue content to detect anomalies, individual problems in specific objects ... More

Abelian Hall Fluids and Edge States: a Conformal Field Theory ApproachMay 08 1995We show that a Coulomb gas Vertex Operator representation of 2D Conformal Field Theory gives a complete description of abelian Hall fluids: as an euclidean theory in two space dimensions leads to the construction of the ground state wave function for ... More

Persistent Currents in Superconducting Quantum Interference DevicesApr 04 2007Jul 26 2007Starting from the reduced dynamical model of a two-junction quantum interference device, a quantum analog of the system has been exhibited, in order to extend the well known properties of this device to the quantum regime. By finding eigenvalues of the ... More

Nuclear parton distributions at next to leading orderNov 18 2003We perform a next to leading order QCD global analysis of nuclear deep inelastic scattering and Drell-Yan data using the convolution approach to parameterize nuclear parton densities. We find both a significant improvement in the agreement with data compared ... More

The Euclidean Scalar Green Function in the Five-Dimensional Kaluza-Klein Magnetic Monopole SpacetimeNov 16 2005In this paper we present, in a integral form, the Euclidean Green function associated with a massless scalar field in the five-dimensional Kaluza-Klein magnetic monopole superposed to a global monopole, admitting a non-trivial coupling between the field ... More

Fermionic vacuum polarization in higher-dimensional global monopole spacetimeAug 16 2007In this paper we analyse the vacuum polarization effects associated with a massless fermionic field in a higher-dimensional global monopole spacetime in the "braneworld" scenario. In this context we admit that the our Universe, the bulk, is represented ... More

Reply to "Comment on 'Gravitating Magnetic Monopole in the Global Monopole Spacetime' "Apr 03 2003Oct 15 2003In this Reply I present some arguments in favor of the stability of the topological defect composed by global and magnetic monopoles.

ESR theory for interacting 1D quantum wiresSep 10 2001We compute the electron spin resonance (ESR) intensity for one-dimensional quantum wires in semiconductor heterostructures, taking into account electron-electron interactions and spin-orbit coupling. The ESR spectrum is shown to be very sensitive to interactions. ... More

The Implicit Function Theorem for maps that are only differentiable: an elementary proofAug 04 2017This article shows a very elementary and straightforward proof of the Implicit Function Theorem for differentiable maps $F(x,y)$ defined on a finite-dimensional Euclidean space. There are no hypothesis on the continuity of the partial derivatives of $F$. ... More

The Initial Mass Function and the Dynamical Evolution of Open Clusters. IV. Realistic SystemsJan 03 1997This paper is the fourth one of a series whose chief objective is studying the influence of different mass spectra on the dynamical evolution of open star clusters. Results from several N-body calculations with primordial binaries and mass loss due to ... More

Mechanical Ringdown Studies of Large-Area Substrate-Transferred GaAs/AlGaAs Crystalline CoatingsNov 14 2018We investigated elastic loss in GaAs/AlGaAs multilayers to help determine the suitability of these coatings for future gravitational wave detectors. We measured large ($\approx 70$-mm diameter) substrate-transferred crystalline coating samples with an ... More

Spiral galaxy distance indicators based on near-infrared photometryJun 17 1999We compare two methods of distance determination to spiral galaxies using optical/near-infrared (NIR) observations, the (I-K) versus M_K colour - absolute magnitude (CM) relation and the I and K-band Tully-Fisher relation (TFR). Dust-free colours and ... More

The shape of galaxy disks: how the scale height increases with galactocentric distanceFeb 25 1997We present the results of a detailed study of vertical surface brightness profiles of edge-on disk galaxies. Although the exponential disk scale height is constant to first order approximation, we show that for the large majority of galaxies in our sample, ... More

The scatter in the near-infrared colour-magnitude relation in spiral galaxiesAug 21 1998We have determined a dust-free colour-magnitude (CM) relation for spiral galaxies, by using I-K colours in edge-on galaxies above the plane. We find that the scatter in this relation is small and approximately as large as can be explained by observational ... More

The Origin of Color Gradients in Early-Type Systems and Their Compactness at High-zMay 06 2009In this Letter, we present mean optical+NIR color gradient estimates for 5080 early-type galaxies (ETGs) in the grizYJHK wavebands of the Sloan Digital Sky Survey (SDSS) plus UKIRT Infrared Deep Sky Survey (UKIDSS). The color gradient is estimated as ... More

Photometric Properties of 47 Clusters of Galaxies: I. The Butcher-Oemler EffectJan 04 2000We present gri CCD photometry of 44 Abell clusters and 4 cluster candidates. Twenty one clusters in our sample have spectroscopic redshifts. Fitting a relation between mean g, r and i magnitudes, and redshift for this subsample, we have calculated photometric ... More

Study of Puncturing Techniques for Polar Codes in 5G Cellular and IoT NetworksDec 10 2018This paper presents a puncturing technique based on the channel polarization index for the design of rate-compatible polar codes in the fifth generation (5G) of wireless systems. The proposed strategy consists of two steps: we first generate the codeword ... More

Understanding the evolution of Atira-class asteroid 2019 AQ3, a major step towards the future discovery of the Vatira populationMay 21 2019May 22 2019Orbiting the Sun at an average distance of 0.59 au and with the shortest aphelion of any known minor body, at 0.77 au, the Atira-class asteroid 2019 AQ3 may be an orbital outlier or perhaps an early indication of the presence of a new population of objects: ... More

Ghosts of Jupiter's past: is 2017 UV43 a relative of comet Shoemaker-Levy 9?Dec 08 2017Dec 13 2017The present-day orbit of 2017 UV43 resembles the average one of the fragments of comet Shoemaker-Levy 9. Here, we present numerical evidence suggesting that 2017 UV43 might be related to Shoemaker-Levy 9. With our exploratory results we intend to encourage ... More

Geometric characterization of the Arjuna orbital domainOct 15 2014Dec 31 2014Arjuna-type orbits are characterized by being Earth-like, having both low-eccentricity and low-inclination. Objects following these trajectories experience repeated trappings in the 1:1 commensurability with the Earth and can become temporary Trojans, ... More

Comparative orbital evolution of transient Uranian co-orbitals: exploring the role of ephemeral multibody mean motion resonancesApr 10 2014Apr 30 2014Uranus has three known co-orbitals: 83982 Crantor (2002 GO9), 2010 EU65 and 2011 QF99. Here, we perform a comparative analysis of the orbital evolution of these transient co-orbitals to understand better how they got captured in the first place and what ... More

Microlensing planets in M22: free-floating or bound?Aug 17 2001We use detailed numerical simulations and theoretical estimates to show that, if confirmed, the unusually brief microlensing events observed by Sahu et al. (2001) in the field of the globular cluster M22 might be explained as a result of microlensing ... More

Finding Planet Nine: apsidal anti-alignment Monte Carlo resultsJul 19 2016Aug 03 2016The distribution of the orbital elements of the known extreme trans-Neptunian objects or ETNOs has been found to be statistically incompatible with that of an unperturbed asteroid population following heliocentric or, better, barycentric orbits. Such ... More

Commensurabilities between ETNOs: a Monte Carlo surveyApr 20 2016May 05 2016Many asteroids in the main and trans-Neptunian belts are trapped in mean motion resonances with Jupiter and Neptune, respectively. As a side effect, they experience accidental commensurabilities among themselves. These commensurabilities define characteristic ... More