Diagnosis and treatment of pseudoachalasia: how to catch the mimic

Published: 25 June 2020Pseudoachalasia, or secondary achalasia, is an uncommon esophageal dysmotility syndrome with symptoms and manometric findings indistinguishable from primary achalasia, but due to any mechanism other than idiopathic degeneration of the inhibitory neurons of the esophageal submucosal myenteric plexus. Whilst pseudoachalasia is rare, affecting some 1.4–5.4% of all achalasia patients, it is essential this diagnosis is always considered and excluded, as the treatment and outcomes for these patients will be very different from those with true achalasia. Pseudoachalasia can be difficult to differentiate from primary or “idiopathic achalasia”. Several particular clinical features have been described as more common in patients with pseudoachalasia than in achalasia, but because of the low prevalence of this condition, the positive predictive value remains low. The majority of patients with pseudoachalasia have an underlying malignancy, predominantly gastro-esophageal adenocarcinoma, which is usually advanced. Management revolves around treating the underlying cause where possible, as this may lead to reversal of the esophageal dysmotility. In patients presenting with symptoms and manometry findings consistent with achalasia, the diagnosis initially should be one of an achalasia-like syndrome. Idiopathic achalasia can then only be confirmed after other potential causes have been considered and excluded. We describe a case of pseudoachalasia encountered in our clinical practice, followed by a review of current practice regarding diagnosis and management of pseudoachalasia.Dylan R. Barnett, George L. Balalis, Jennifer C. Myers, Peter G. Devit

Rational foundation of GR in terms of statistical mechanic in the AdS/CFT framework

In this article, we work out the microscopic statistical foundation of the supergravity description of the simplest 1/2 BPS sector in the AdS(5)/CFT(4). Then, all the corresponding supergravity observables are related to thermodynamical observables, and General Relativity is understood as a mean-field theory. In particular, and as an example, the Superstar is studied and its thermodynamical properties clarified.Comment: 13 pages, 6 eps figures, latex, some improvements introduced, reference added, typos correcte

Theory of Multiphonon Excitation in Heavy-Ion Collisions

We study the effects of channel coupling in the excitation dynamics of giant resonances in relativistic heavy ions collisions. For this purpose, we use a semiclassical approximation to the Coupled-Channels problem and separate the Coulomb and the nuclear parts of the coupling into their main multipole components. In order to assess the importance of multi-step processes, we neglect the resonance widths and solve the set of coupled equations exactly. Finite widths are then considered. In this case, we handle the coupling of the ground state with the dominant Giant Dipole Resonance exactly and study the excitation of the remaining resonances within the Coupled-Channels Born Approximation. A comparison with recent experimental data is made.Comment: 29 pages, 7 Postscript figures available upon reques

Counter-propagating entangled photons from a waveguide with periodic nonlinearity

The conditions required for spontaneous parametric down-conversion in a waveguide with periodic nonlinearity in the presence of an unguided pump field are established. Control of the periodic nonlinearity and the physical properties of the waveguide permits the quasi-phase matching equations that describe counter-propagating guided signal and idler beams to be satisfied. We compare the tuning curves and spectral properties of such counter-propagating beams to those for co-propagating beams under typical experimental conditions. We find that the counter-propagating beams exhibit narrow bandwidth permitting the generation of quantum states that possess discrete-frequency entanglement. Such states may be useful for experiments in quantum optics and technologies that benefit from frequency entanglement.Comment: submitted to Phys. Rev.

Coarse-Graining the Lin-Maldacena Geometries

The Lin-Maldacena geometries are nonsingular gravity duals to degenerate vacuum states of a family of field theories with SU(2|4) supersymmetry. In this note, we show that at large N, where the number of vacuum states is large, there is a natural `macroscopic' description of typical states, giving rise to a set of coarse-grained geometries. For a given coarse-grained state, we can associate an entropy related to the number of underlying microstates. We find a simple formula for this entropy in terms of the data that specify the geometry. We see that this entropy function is zero for the original microstate geometries and maximized for a certain ``typical state'' geometry, which we argue is the gravity dual to the zero-temperature limit of the thermal state of the corresponding field theory. Finally, we note that the coarse-grained geometries are singular if and only if the entropy function is non-zero.Comment: 29 pages, LaTeX, 3 figures; v2 references adde

Inhaltliche und erzieherische Kompetenzen im Lernprozess

Prije nego će progovoriti o sadržajnim i odgojnim kompetencijama u procesu učenja, autor podsjeća na podrijetlo i razlog govora o kompetencijama u obrazovanju u Europskoj Uniji i u Hrvatskoj. Početni poticaj dolazi iz ekonomskih krugova radi osiguranja učinkovitosti pojedinih kompanija i povećavanja zaposlenosti i konkurentnosti. Početno zanimanje za jezične i tehničke kompetencije za društvo znanja radi održanja i povećanja europske ekonomske i gospodarske konkurentnosti s vremenom je primijenjeno i na sveukupno odgojno–obrazovno područje. U obrazovnim sustavima pojedinih europskih zemalja i u njihovim nacionalnim obrazovnim standardima, planovima i programima spominju se i kompetencije koje se odnose na vjeronauk kao školski predmet. U članku se posebno razmatra dokument njemačkih biskupa koji govori o uključivanju školskog vjeronauka u njemački obrazovni standard u četverogodišnjoj osnovnoj školi. Razmatraju se specifične sadržajne i odgojne kompetencije vjeroučitelja i vjeroučenika. Tvrdi se kako ispravnim vrednovanjem odgojno–obrazovne funkcije škole vjeronauk može postati i ostati predmet koji promiče i podržava sadržajne i odgojne kompetencije vjeroučitelja i vjeroučenika. Time će ujedno doprinijeti i boljitku i napretku hrvatske škole i društva općenito.Before discussing the content and educational competence in the learning process the author recalls the origin and reason for the debate regarding competence in education in the European Union and Croatia. The initial impetus came from economic circles to secure the performance of individual companies and increase employment and competitiveness. The initial interest in the linguistic and technical competence for a society of knowledge for the sake of maintaining and increasing Europe\u27s economic and financial competitiveness over time has been applied overall to the area of education. The educational systems of some European countries in their national educational standards, plans and programs mention various competencies related to religion as a school subject. The article specifically discusses a document of the German bishops regarding the inclusion of religious instruction within the German educational standard in the first four years of primary school. The document reflects upon specific content and educational competencies regarding religion teachers and pupils enrolled in religion class. Through the proper evaluation of educational functions of the school, religion can become and remain a subject that promotes and supports the content and educational competence of teachers of religion and its pupils. This will also contribute to the improvement and progress of Croatian schools and society in general.Vor der Behandlung der inhaltlichen und erzieherischen Kompetenzen im Lernprozess erinnert der Autor auf den Ursprung und den Grund der Rede über Kompetenzen in der Bildung in der EU und in Kroatien. Der erste Impuls kommt aus den wirtschaftlichen Kreisen, damit dadurch die Effektivität einzelner Firmen und Gesellschaften gesichert wird und dass die Arbeitnehmerzahl sowie die Konkurrenzfähigkeit gesteigert werden. Das anfängliche Interesse für sprachliche und technische Kompetenzen zwecks Erzielung einer Wissens-Gesellschaft, damit europäische ökonomische und wirtschaftliche Konkurrenzfähigkeit aufrechterhalten und vergrössert werden kann, ist mit der Zeit auch auf den gesamten Bildungsbereich angewandt worden. In den Bildungssystemen einzelner europäischen Länder und in ihren nationalen Bildungsstandarden, Plänen und Programmen werden auch Kompetenzen erwähnt, die sich auf den Religionsunterricht als Schulfach beziehen. In diesem Artikel wird besonders das Dokument der deutschen Bischöfe betrachtet, in dem von der Eingliederung des schulischen Religionsunterrichts in den Bildungsstandard der vierjährigen Grundschule die Rede ist. Es werden spezifische inhaltliche und pädagogische Kompetenzen der Religionslehrer sowie der Religionsschüler betrachtet. Es wird darauf aufmerksam gemacht, dass durch richtige Bewertung der erzieherischen und bildenden Funktion der Schule der Religionsunterricht ein Schulfach werden und bleiben kann, der inhaltliche und erzieherische Kompetenzen der Religionslehrer sowie der Religionsschüler fördert und unterstützt. Dadurch wird er auch dem Wohlergehen und dem Fortschritt der kroatischen Schule und der Gesellschaft insgesamt beitragen

An Improved Quantum Molecular Dynamics Model and its Applications to Fusion Reaction near Barrier

An improved Quantum Molecular Dynamics model is proposed. By using this model, the properties of ground state of nuclei from $^{6}$Li to $^{208}$Pb can be described very well with one set of parameters. The fusion reactions for $^{40}$Ca+$^{90}$Zr, $^{40}$Ca+$^{96}$Zr and $^{48}$Ca+$^{90}$Zr at energy near barrier are studied by this model. The experimental data of the fusion cross sections for $^{40}$Ca+$^{90,96}$Zr at the energy near barrier can be reproduced remarkably well without introducing any new parameters. The mechanism for the enhancement of fusion probability for fusion reactions with neutron-rich projectile or target is analyzed.Comment: 20 pages, 12 figures, 3 table

The Giant Inflaton

We investigate a new mechanism for realizing slow roll inflation in string theory, based on the dynamics of p anti-D3 branes in a class of mildly warped flux compactifications. Attracted to the bottom of a warped conifold throat, the anti-branes then cluster due to a novel mechanism wherein the background flux polarizes in an attempt to screen them. Once they are sufficiently close, the M units of flux cause the anti-branes to expand into a fuzzy NS5-brane, which for rather generic choices of p/M will unwrap around the geometry, decaying into D3-branes via a classical process. We find that the effective potential governing this evolution possesses several epochs that can potentially support slow-roll inflation, provided the process can be arranged to take place at a high enough energy scale, of about one or two orders of magnitude below the Planck energy; this scale, however, lies just outside the bounds of our approximations.Comment: 31 pages, 4 figures, LaTeX. v2: references added, typos fixe

Semi-classical Probe Strings on Giant Gravitons Backgrounds

In the first part of this paper we study two $Z_2$ symmetries of the LLM metric, both of which exchange black and white regions. One of them which can be interpreted as the particle-hole symmetry is the symmetry of the whole supergravity solution while the second one is just the symmetry of the metric and changes the sign of the fivefrom flux. In the second part of the paper we use closed string probes and their semi-classical analysis to compare the two 1/2 BPS deformations of $AdS_5\times S^5$, the smooth LLM geometry which contains localized giant gravitons and the superstar case which is a solution with naked singularity corresponding to smeared giants. We discuss the realization of the $Z_2$ symmetry in the semi-classical closed string probes point of view.Comment: 29 pages, 6 .eps figures; v2: References adde

Extended Fermion Representation of Multi-Charge 1/2-BPS Operators in AdS/CFT -- Towards Field Theory of D-Branes --

We extend the fermion representation of single-charge 1/2-BPS operators in the four-dimensional N=4 super Yang-Mills theory to general (multi-charge) 1/2-BPS operators such that all six directions of scalar fields play roles on an equal footing. This enables us to construct a field-theorectic representation for a second-quantized system of spherical D3-branes in the 1/2-BPS sector. The Fock space of D3-branes is characterized by a novel exclusion principle (called `Dexclusion' principle), and also by a nonlocality which is consistent with the spacetime uncertainty relation. The Dexclusion principle is realized by composites of two operators, obeying the usual canonical anticommutation relation and the Cuntz algebra, respectively. The nonlocality appears as a consequence of a superselction rule associated with a symmetry which is related to the scale invariance of the super Yang-Mills theory. The entropy of the so-called superstars, with multiple charges, which have been proposed to be geometries corresponding to the condensation of giant gravitons is discussed from our viewpoint and is argued to be consistent with the Dexclusion principle. Our construction may be regarded as a first step towards a possible new framework of general D-brane field theory.Comment: 43 pages, 4 figures; version 2, corrected typos and added reference