Gastroesophageal reflux and idiopathic pulmonary fibrosis: A prospective study

Background and Objective: Idiopathic pulmonary fibrosis (IPF) is the most common of the idiopathic interstitial pneumonias. There is evidence of the increased prevalence of gastroesophageal reflux disease in patients with IPF. The aim of this prospective study was to evaluate reflux in patients with IPF by analyzing the scores of the reflux cough questionnaire, measurement of pepsin in exhaled breath condensate (EBC) to detect extraesophageal reflux, and Helicobacter pylori serology to evaluate the prevalence of this stomach bacterium in patients with IPF. Material and Methods: The Hull airway reflux questionnaire (HARQ) was completed by 40 patients with IPF and 50 controls in order to evaluate reflux symptoms. EBC was collected from 23 patients (17 patients with IPF and 6 controls) for measurement of pepsin by the lateral flow technique. A prospective study of 57 subjects (34 patients with IPF and 23 controls) for H. pylori antibody detection by ELISA was performed. Results: Significantly higher HARQ scores (maximum score, 70) were recorded in patients with IPF compared with controls (19.6 [SD, 12.4] vs. 3 [SD, 2.9],

Aging, jamming, and the limits of stability of amorphous solids

Apart from not having crystallized, supercooled liquids can be considered as being properly equilibrated and thus can be described by a few thermodynamic control variables. In contrast, glasses and other amorphous solids can be arbitrarily far away from equilibrium and require a description of the history of the conditions under which they formed. In this paper we describe how the locality of interactions intrinsic to finite-dimensional systems affects the stability of amorphous solids far off equilibrium. Our analysis encompasses both structural glasses formed by cooling and colloidal assemblies formed by compression. A diagram outlining regions of marginal stability can be adduced which bears some resemblance to the quasi-equilibrium replica meanfield theory phase diagram of hard sphere glasses in high dimensions but is distinct from that construct in that the diagram describes not true phase transitions but kinetic transitions that depend on the preparation protocol. The diagram exhibits two distinct sectors. One sector corresponds to amorphous states with relatively open structures, the other to high density, more closely-packed ones. The former transform rapidly owing to there being motions with no free energy barriers; these motions are string-like locally. In the dense region, amorphous systems age via compact activated reconfigurations. The two regimes correspond, in equilibrium, to the collisional or uniform liquid and the so called landscape regime, respectively. These are separated by a spinodal line of dynamical crossovers. Owing to the rigidity of the surrounding matrix in the landscape, high-density part of the diagram, a sufficiently rapid pressure quench adds compressive energy which also leads to an instability toward string-like motions with near vanishing barriers. (SEE REST OF ABSTRACT IN THE ARTICLE.)Comment: submitted to J Phys Chem

Absorption imaging of a quasi 2D gas: a multiple scattering analysis

Absorption imaging with quasi-resonant laser light is a commonly used technique to probe ultra-cold atomic gases in various geometries. Here we investigate some non-trivial aspects of this method when it is applied to in situ diagnosis of a quasi two-dimensional gas. Using Monte Carlo simulations we study the modification of the absorption cross-section of a photon when it undergoes multiple scattering in the gas. We determine the variations of the optical density with various parameters, such as the detuning of the light from the atomic resonance and the thickness of the gas. We compare our results to the known three-dimensional result (Beer-Lambert law) and outline the specific features of the two-dimensional case.Comment: 22 pages, 5 figure

Risk Profile and 3-Year Outcomes From the SYNTAX Percutaneous Coronary Intervention and Coronary Artery Bypass Grafting Nested Registries

ObjectivesThe aim of this study was to evaluate the use of percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) in “real-world” patients unsuitable for the alternative treatment.BackgroundNo data are available on the risk profile and outcomes of patients that can only undergo PCI or CABG.MethodsIn the SYNTAX (Synergy between PCI with TAXUS and Cardiac Surgery) trial, a multidisciplinary Heart Team reached a consensus on whether PCI and CABG could result in clinical equipoise; if so, the patient was randomized. If not, the patient was enrolled in a CABG-ineligible PCI registry or PCI-ineligible CABG registry. A proportion (60%) of patients in the CABG registry was randomly assigned to be followed up for 5 years. No statistical comparisons were performed between randomized and registry patients. Major adverse cardiac or cerebrovascular event (MACCE) rates are presented as observational only.ResultsA total of 3,075 patients were treated in the SYNTAX trial; 198 (6.4%) and 1,077 (35.0%) patients were included in PCI and CABG registries, respectively. The main reason for inclusion in the CABG registry was too complex coronary anatomy (70.9%), and the main reason for inclusion in the PCI registry was too high-risk for surgery (70.7%). Three-year MACCE was 38.0% after PCI and 16.4% after CABG. Stratification by SYNTAX score terciles demonstrated a step-wise increase of MACCE rates in both PCI and CABG registries.ConclusionsThe SYNTAX Heart Team concluded that PCI and CABG remained the only treatment options for 6.4% and 35.0% of patients, respectively. Inoperable patients with major comorbidities that underwent PCI had high MACCE rates. In patients not suitable for PCI, surgical results were excellent. (SYNTAX Study: TAXUS Drug-Eluting Stent Versus Coronary Artery Bypass Surgery for the Treatment of Narrowed Arteries, NCT00114972

Safe Transfert of Medical Images by Conjoined Coding : Selective Encryption by AES Using the Stream Cipher Mode OFB and JPEG Compression

The traffic of digital images has increased rapidly in the wide networks. The protection of this kind of data becomes important for many reasons such as confidentiality, obscurity and security. Nowadays, the most important engine to provide confidentiality is encryption. Therefore, the classical and modern ciphers are not suitable for such huge quantity of data in real-time environment. Selective encryption (SE) is an approach to encode a portion of the data in order to reduce computational requirements and to provide a proportional privacy. This paper presents a new method of partial or selective encryption for JPEG images. It is based on encoding of some Huffman bitstream with AES cipher. The proposed method results in a significant reduction in encrypting and decrypting processing time, provides a constant bit rate and keeps the JPEG bitstream compliance.Le trafic des images numériques augmente rapidement sur les réseaux. La protection des données numériques, et en particulier les images médicales, devient importante pour de nombreuses raisons telles que la confidentialité et l'intégrité. Actuellement, la façon la plus répandue de répondre au problème de la confidentialité est le cryptage. Cependant, les algorithmes classiques et modernes de chiffrement ne sont pas capables de chiffrer une énorme quantité de données dans un environnement en temps réel. Le cryptage sélectif (CS) est une approche qui ne chiffre qu'une partie des données afin de diminuer le temps de calcul tout en assurant une certaine sécurité. Cet article présente une nouvelle méthode de cryptage sélectif pour des images médicales comprimées au format JPEG. Cette méthode est basée sur le cryptage par flot avec AES d'une partie du flux binaire issue du codage par Huffman. Les résultats de la méthode proposée présentent un gain de temps de calcul significatif tout en conservant le taux de compression et le format initial de JPEG

Interference scheme to measure light-induced nonlinearities in Bose-Einstein condensates

Light-induced nonlinear terms in the Gross-Pitaevskii equation arise from the stimulated coherent exchange of photons between two atoms. For atoms in an optical dipole trap this effect depends on the spatial profile of the trapping laser beam. Two different laser beams can induce the same trapping potential but very different nonlinearities. We propose a scheme to measure light-induced nonlinearities which is based on this observation.Comment: 2 figure

Optical linewidth of a low density Fermi-Dirac gas

We study propagation of light in a Fermi-Dirac gas at zero temperature. We analytically obtain the leading density correction to the optical linewidth. This correction is a direct consequence of the quantum statistical correlations of atomic positions that modify the optical interactions between the atoms at small interatomic separations. The gas exhibits a dramatic line narrowing already at very low densities.Comment: 4 pages, 2 figure

Treatment of bronchial airway obstruction using a rotating tip microdebrider: a case report

BACKGROUND: Central airway obstruction is a common complication of lung cancer. The microdebrider is a new device available for treatment of central airway obstruction. CASE DESCRIPTION: We report a case a 59-yr-old male with T3N2M1 non-small cell lung cancer with malignant distal left mainstem obstruction treated successfully with a novel elongated rotating tip microdebrider via rigid bronchoscopy with sufficient length to reach distal bronchial lesions. DISCUSSION AND CONCLUSION: The microdebrider is an excellent addition to the spectrum of interventions available for the management of central airway obstruction with advantages including accuracy and immediate removal of debris without a need for separate suctioning or limitation in oxygenation

Quantum field theory of cooperative atom response: Low light intensity

We study the interactions of a possibly dense and/or quantum degenerate gas with driving light. Both the atoms and the electromagnetic fields are represented by quantum fields throughout the analysis. We introduce a field theory version of Markov and Born approximations for the interactions of light with matter, and devise a procedure whereby certain types of products of atom and light fields may be put to a desired, essentially normal, order. In the limit of low light intensity we find a hierarchy of equations of motion for correlation functions that contain one excited-atom field and one, two, three, etc., ground state atom fields. It is conjectured that the entire linear hierarchy may be solved by solving numerically the classical equations for the coupled system of electromagnetic fields and charged harmonic oscillators. We discuss the emergence of resonant dipole-dipole interactions and collective linewidths, and delineate the limits of validity of the column density approach in terms of non-cooperative atoms by presenting a mathematical example in which this approach is exact.Comment: 35 pages, RevTe