358 research outputs found

    Successful Non-Invasive treatment of stricturing fibrosing colonopathy in an adult patient

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    <p>Abstract</p> <p>Objective</p> <p>Fibrosing colonopathy (FC) is a rare entity associated with cystic fibrosis (CF). Until now, patients with stricturing FC have usually been treated surgically. In this instance, we aimed at avoiding surgery by applying a new conservative approach.</p> <p>Methods</p> <p>Case report on an adult with CF who developed persistent abdominal pain due to a non-passable stricture in the right transverse colon. Histology confirmed fibrosing colonopathy.</p> <p>Results</p> <p>Initially we treated the patient with prednisolone pulse therapy and additive antibiotic therapy. For maintenance therapy we administered budesonide. The patient underwent clinical, laboratory and endoscopic follow-up over a three-year period. The stricture healed and was easy to pass. A relapse in the cecum at the ileocecal valve again improved under steroid and antibiotic therapy.</p> <p>Conclusions</p> <p>We present a novel therapeutic approach for advanced stricturing FC in an adult patient which successfully avoided surgery (right hemicolectomy) over a three year follow up.</p

    Hidden order in bosonic gases confined in one dimensional optical lattices

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    We analyze the effective Hamiltonian arising from a suitable power series expansion of the overlap integrals of Wannier functions for confined bosonic atoms in a 1d optical lattice. For certain constraints between the coupling constants, we construct an explicit relation between such an effective bosonic Hamiltonian and the integrable spin-SS anisotropic Heisenberg model. Therefore the former results to be integrable by construction. The field theory is governed by an anisotropic non linear σ\sigma-model with singlet and triplet massive excitations; such a result holds also in the generic non-integrable cases. The criticality of the bosonic system is investigated. The schematic phase diagram is drawn. Our study is shedding light on the hidden symmetry of the Haldane type for one dimensional bosons.Comment: 5 pages; 1 eps figure. Revised version, to be published in New. J. Phy

    Systematic Density Expansion of the Lyapunov Exponents for a Two-dimensional Random Lorentz Gas

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    We study the Lyapunov exponents of a two-dimensional, random Lorentz gas at low density. The positive Lyapunov exponent may be obtained either by a direct analysis of the dynamics, or by the use of kinetic theory methods. To leading orders in the density of scatterers it is of the form A0n~lnn~+B0n~A_{0}\tilde{n}\ln\tilde{n}+B_{0}\tilde{n}, where A0A_{0} and B0B_{0} are known constants and n~\tilde{n} is the number density of scatterers expressed in dimensionless units. In this paper, we find that through order (n~2)(\tilde{n}^{2}), the positive Lyapunov exponent is of the form A0n~lnn~+B0n~+A1n~2lnn~+B1n~2A_{0}\tilde{n}\ln\tilde{n}+B_{0}\tilde{n}+A_{1}\tilde{n}^{2}\ln\tilde{n} +B_{1}\tilde{n}^{2}. Explicit numerical values of the new constants A1A_{1} and B1B_{1} are obtained by means of a systematic analysis. This takes into account, up to O(n~2)O(\tilde{n}^{2}), the effects of {\it all\/} possible trajectories in two versions of the model; in one version overlapping scatterer configurations are allowed and in the other they are not.Comment: 12 pages, 9 figures, minor changes in this version, to appear in J. Stat. Phy

    Exact results on the Kitaev model on a hexagonal lattice: spin states, string and brane correlators, and anyonic excitations

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    In this work, we illustrate how a Jordan-Wigner transformation combined with symmetry considerations enables a direct solution of Kitaev's model on the honeycomb lattice. We (i) express the p-wave type fermionic ground states of this system in terms of the original spins, (ii) adduce that symmetry alone dictates the existence of string and planar brane type correlators and their composites, (iii) compute the value of such non-local correlators by employing the Jordan-Wigner transformation, (iv) affirm that the spectrum is inconsequential to the existence of topological quantum order and that such information is encoded in the states themselves, and (v) express the anyonic character of the excitations in this system and the local symmetries that it harbors in terms of fermions.Comment: 14 pages, 7 figure

    An introduction to network psychometrics:Relating ising network models to item response theory models

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    In recent years, network models have been proposed as an alternative representation of psychometric constructs such as depression. In such models, the covariance between observables (e.g., symptoms like depressed mood, feelings of worthlessness, and guilt) is explained in terms of a pattern of causal interactions between these observables, which contrasts with classical interpretations in which the observables are conceptualized as the effects of a reflective latent variable. However, few investigations have been directed at the question how these different models relate to each other. To shed light on this issue, the current paper explores the relation between one of the most important network models—the Ising model from physics—and one of the most important latent variable models—the Item Response Theory (IRT) model from psychometrics. The Ising model describes the interaction between states of particles that are connected in a network, whereas the IRT model describes the probability distribution associated with item responses in a psychometric test as a function of a latent variable. Despite the divergent backgrounds of the models, we show a broad equivalence between them and also illustrate several opportunities that arise from this connection

    Improved Modeling of Residential Air Conditioners and Heat Pumps for Energy Calculations

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    This report presents improved air conditioner and heat pump modeling methods in the context of whole-building simulation tools, with the goal of enabling more accurate evaluation of cost effective equipment upgrade opportunities and efficiency improvements in residential buildings

    Bowel Preparation for Colonoscopy with Sodium Phosphate Solution versus Polyethylene Glycol-Based Lavage: A Multicenter Trial

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    Background: Adequate bowel preparation is essential for accurate colonoscopy. Both oral sodium phosphate (NaP) and polyethylene glycol-based lavage (PEG-ELS) are used predominantly as bowel cleansing modalities. NaP has gained popularity due to low drinking volume and lower costs. The purpose of this randomized multicenter observer blinded study was to compare three groups of cleansing (NaP, NaP + sennosides, PEG-ELS + sennosides) in reference to tolerability, acceptance, and cleanliness. Patient and Methods: 355 outpatients between 18 and 75 years were randomized into three groups (A, B, C) receiving NaP = A, NaP, and sennosides = B or PEG-ELS and sennosides = C. Gastroenterologists performing colonoscopies were blinded to the type of preparation. All patients documented tolerance and adverse events. Vital signs, premedication, completeness, discomfort, and complications were recorded. A quality score (0–4) of cleanliness was generated. Results: The three groups were similar with regard to age, sex, BMI, indication for colonoscopy, and comorbidity. Drinking volumes (L) (A = 4.33 + 1.2, B = 4.56 + 1.18, C = 4.93 + 1.71) were in favor of NaP (P = .005). Discomfort from ingested fluid was recorded in A = 39.8% (versus C: P = .015), B = 46.6% (versus C: P = .147), and C = 54.6%. Differences in tolerability and acceptance between the three groups were statistically not significant. No differences in adverse events and the cleanliness effects occurred in the three groups (P = .113). The cleanliness quality scores 0–2 were calculated in A: 77.7%, B: 86.7%, and C: 85.2%. Conclusions: These data fail to demonstrate significant differences in tolerability, acceptance, and preparation quality between the three types of bowel preparation for colonoscopy. Cleansing with NaP was not superior to PEG-ELS
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