Exact Solution of the one-impurity quantum Hall problem

The problem of a non-relativistic electron in the presence of a uniform electromagnetic field and of one impurity, described by means of an Aharonov-Bohm point-like vortex, is studied. The exact solution is found and the quantum Hall's conductance turns out to be the same as in the impurity-free case. This exactly solvable model seems to give indications, concerning the possible microscopic mechanisms underlying the integer quantum Hall effect, which sensibly deviate from some proposals available in the literature.Comment: 25 pages, TeX, to appear in J. Phys.

The Casimir Effect for Parallel Plates Revisited

The Casimir effect for a massless scalar field with Dirichlet and periodic boundary conditions (b.c.) on infinite parallel plates is revisited in the local quantum field theory (lqft) framework introduced by B.Kay. The model displays a number of more realistic features than the ones he treated. In addition to local observables, as the energy density, we propose to consider intensive variables, such as the energy per unit area $\epsilon$, as fundamental observables. Adopting this view, lqft rejects Dirichlet (the same result may be proved for Neumann or mixed) b.c., and accepts periodic b.c.: in the former case $\epsilon$ diverges, in the latter it is finite, as is shown by an expression for the local energy density obtained from lqft through the use of the Poisson summation formula. Another way to see this uses methods from the Euler summation formula: in the proof of regularization independence of the energy per unit area, a regularization-dependent surface term arises upon use of Dirichlet b.c. but not periodic b.c.. For the conformally invariant scalar quantum field, this surface term is absent, due to the condition of zero trace of the energy momentum tensor, as remarked by B.De Witt. The latter property does not hold in tha application to the dark energy problem in Cosmology, in which we argue that periodic b.c. might play a distinguished role.Comment: 25 pages, no figures, late

The gauge theory of dislocations: static solutions of screw and edge dislocations

We investigate the T(3)-gauge theory of static dislocations in continuous solids. We use the most general linear constitutive relations bilinear in the elastic distortion tensor and dislocation density tensor for the force and pseudomoment stresses of an isotropic solid. The constitutive relations contain six material parameters. In this theory both the force and pseudomoment stresses are asymmetric. The theory possesses four characteristic lengths l1, l2, l3 and l4 which are given explicitely. We first derive the three-dimensional Green tensor of the master equation for the force stresses in the translational gauge theory of dislocations. We then investigate the situation of generalized plane strain (anti-plane strain and plane strain). Using the stress function method, we find modified stress functions for screw and edge dislocations. The solution of the screw dislocation is given in terms of one independent length l1=l4. For the problem of an edge dislocation, only two characteristic lengths l2 and l3 arise with one of them being the same l2=l1 as for the screw dislocation. Thus, this theory possesses only two independent lengths for generalized plane strain. If the two lengths l2 and l3 of an edge dislocation are equal, we obtain an edge dislocation which is the gauge theoretical version of a modified Volterra edge dislocation. In the case of symmetric stresses we recover well known results obtained earlier.Comment: 33 pages, 17 figure

Disk diffusion method for fluconazole susceptibility testing of Candida spp. isolates

Fil: Rodero, L. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Micología; Argentina.Fil: Córdoba, Susana. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Micología; Argentina.Fil: Vivot, W. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Micología; Argentina.Fil: Campo, M. Universidad Católica Argentina. Cátedra de Microbiología; Argentina.Fil: Corfield, P. Universidad Católica Argentina. Cátedra de Microbiología; Argentina.Fil: Olguín, C. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Micología; Argentina.Fil: Cuirolo, A. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Micología; Argentina.Fil: Soria, M. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Micología; Argentina.Fil: Guelfand, L. Universidad Católica Argentina. Cátedra de Microbiología; Argentina.Fil: Canteros, C. E. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Micología; Argentina.Fil: Davel, Graciela Odelsia. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Micología; Argentina.Fil: Red de Vigilancia de la Resistencia a los Antimicrobianos WHONET; Argentina.Se estudiaron 1193 aislamientos clínicos para estandarizar y evaluar un método de difusión con discos de fluconazol de lectura visual, que permita detectar levaduras sensibles al antifúngico. Las especies analizadas fueron: Candida albicans (n=584), Candida parapsilosis (n=196), Candida tropicalis (n=200), Candida glabrata (n=113), Candida krusei (n=50), Candida spp. y otras levaduras oportunistas (n=50). Los discos fueron manufacturados en el INEIANLIS “Dr. Carlos G. Malbrán”. Se midieron los halos de inhibición del crecimiento producidos por fluconazol y la concentración inhibitoria mínima (CIM) por el método de referencia M27-A2 modificado por EUCAST. Se establecieron los valores de corte del método de difusión en: ³ 16 mm para levaduras sensibles a fluconazol (CIM £ 8 μg/ml), entre 9 y 15 mm para sensibles dependientes de la dosis (CIM = 16-32 mg/ml) y £ 8 mm para resistentes (CIM ³ 64 μg/ml). El método de difusión tuvo 94,7% de concordancia con el de referencia, con 0,2% de errores very major y 0,3% de errores major. La reproducibilidad inter e intralaboratorio fue muy buena. Para detectar aislamientos sensibles a fluconazol, este método resulta confiable y de bajo costo; sin embargo, es conveniente que los aislamientos con halos £ 15 mm sean reevaluados por el método de referencia. (EN) In order to standardize and evaluate a disk diffusion method with visual reading to detect in vitro fluconazole susceptibility of yeast, 1193 clinical isolates were tested. These included 584 Candida albicans, 196 Candida parapsilosis, 200 Candida tropicalis, 113 Candida glabrata, 50 Candida krusei and 50 Candida spp. and other opportunistic yeasts. The disks were manufactured in the INEI-ANLIS “Dr. Carlos G. Malbrán”. The disk diffusion method results were compared to MIC results obtained by the reference CLSI M27-A2 broth microdilution method modified by EUCAST. The interpretative breakpoints for in vitro susceptibility testing of fluconazole were established at: zone diameter ³ 16 mm for MIC £ 8 μg/ml (susceptible isolates), between 9 and 15 mm for MIC = 16-32 mg/ml (susceptible dose-dependent isolates), and £ 8 mm for MIC ³ 64 μg/ml (resistant isolates). Overall agreement between the two methods was 94.7%, with 0.2% very major errors, and 0.3% major errors. Inter - and intralaboratory agreement was good. The disk diffusion method for drug susceptibility testing of Candida spp. isolates is inexpensive, reliable and reproducible. However, when the inhibition zone diameter is £ 15 mm, it is advisable to test the isolate by the reference microdilution method

Disk diffusion method for fluconazole susceptibility testing of Candida spp. isolates

Fil: Rodero, L. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Micología; Argentina.Fil: Córdoba, Susana. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Micología; Argentina.Fil: Vivot, W. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Micología; Argentina.Fil: Campo, M. Universidad Católica Argentina. Cátedra de Microbiología; Argentina.Fil: Corfield, P. Universidad Católica Argentina. Cátedra de Microbiología; Argentina.Fil: Olguín, C. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Micología; Argentina.Fil: Cuirolo, A. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Micología; Argentina.Fil: Soria, M. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Micología; Argentina.Fil: Guelfand, L. Universidad Católica Argentina. Cátedra de Microbiología; Argentina.Fil: Canteros, C. E. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Micología; Argentina.Fil: Davel, Graciela Odelsia. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Micología; Argentina.Fil: Red de Vigilancia de la Resistencia a los Antimicrobianos WHONET; Argentina.Se estudiaron 1193 aislamientos clínicos para estandarizar y evaluar un método de difusión con discos de fluconazol de lectura visual, que permita detectar levaduras sensibles al antifúngico. Las especies analizadas fueron: Candida albicans (n=584), Candida parapsilosis (n=196), Candida tropicalis (n=200), Candida glabrata (n=113), Candida krusei (n=50), Candida spp. y otras levaduras oportunistas (n=50). Los discos fueron manufacturados en el INEIANLIS “Dr. Carlos G. Malbrán”. Se midieron los halos de inhibición del crecimiento producidos por fluconazol y la concentración inhibitoria mínima (CIM) por el método de referencia M27-A2 modificado por EUCAST. Se establecieron los valores de corte del método de difusión en: ³ 16 mm para levaduras sensibles a fluconazol (CIM £ 8 μg/ml), entre 9 y 15 mm para sensibles dependientes de la dosis (CIM = 16-32 mg/ml) y £ 8 mm para resistentes (CIM ³ 64 μg/ml). El método de difusión tuvo 94,7% de concordancia con el de referencia, con 0,2% de errores very major y 0,3% de errores major. La reproducibilidad inter e intralaboratorio fue muy buena. Para detectar aislamientos sensibles a fluconazol, este método resulta confiable y de bajo costo; sin embargo, es conveniente que los aislamientos con halos £ 15 mm sean reevaluados por el método de referencia. (EN) In order to standardize and evaluate a disk diffusion method with visual reading to detect in vitro fluconazole susceptibility of yeast, 1193 clinical isolates were tested. These included 584 Candida albicans, 196 Candida parapsilosis, 200 Candida tropicalis, 113 Candida glabrata, 50 Candida krusei and 50 Candida spp. and other opportunistic yeasts. The disks were manufactured in the INEI-ANLIS “Dr. Carlos G. Malbrán”. The disk diffusion method results were compared to MIC results obtained by the reference CLSI M27-A2 broth microdilution method modified by EUCAST. The interpretative breakpoints for in vitro susceptibility testing of fluconazole were established at: zone diameter ³ 16 mm for MIC £ 8 μg/ml (susceptible isolates), between 9 and 15 mm for MIC = 16-32 mg/ml (susceptible dose-dependent isolates), and £ 8 mm for MIC ³ 64 μg/ml (resistant isolates). Overall agreement between the two methods was 94.7%, with 0.2% very major errors, and 0.3% major errors. Inter - and intralaboratory agreement was good. The disk diffusion method for drug susceptibility testing of Candida spp. isolates is inexpensive, reliable and reproducible. However, when the inhibition zone diameter is £ 15 mm, it is advisable to test the isolate by the reference microdilution method

Data for: MANAGEMENT OF GIANT OMPHALOCELE WITH A SIMPLE AND EFFICIENT NON-SURGICAL SILO

RESULTADOS EXPERIENCIA SILO NO QUIRÚRGICO PARA RECIÉN NACIDOS CON ONFALOCELE GIGANTETHIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV

Laparoscopic excision of a gastric duplication cyst detected on antenatal ultrasound scan

Art. no. E38 Copyright © 2004 Elsevier Inc. All rights reserved.W.D.A. Ford, M. Guelfand, P.J. Lopez, and M.E. Furnesshttp://www.elsevier.com/wps/find/journaldescription.cws_home/623148/description#descriptio

Thoracoscopic repair of esophageal atresia with and without tracheoesophageal fistula Reparación toracoscópica de atresia esofágica con y sin fistula traqueoesofágica

© 2014, Sociedad Chilena de Pediatria. All rights reserved. Introduction: Esophageal atresia (EA) is the interruption of the continuity of the esophagus, with or without persistent communication with the trachea. Recent advances in surgical techniques have made possible correction with minimally invasive surgery (MIS). Objective: To evaluate the management of thoracoscopic technique in the treatment of EA. Patients and Method: Retrospective analysis of medical records in two centers was carried out between 2007 and 2012. Variables such as gestational age, gender, weight, type of esophageal atresia, malformations, surgery and postoperative complications were recorded. Results: Twenty patients, 15 of them with type III EA, 4 with type I and one unclassifiable, were part of the study. 13 patients underwent ligation, cut of tracheoesophageal fistula and end to end anastomosis. Two underwent laparoscopic gastrostomy and fistula ligation. One patient required conversion and underwent esopha