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Full-Text Articles in Physics
Transforming Fabry-Pérot Resonances Into A Tamm Mode, Maxim Durach, Anastasia Rusina
Transforming Fabry-Pérot Resonances Into A Tamm Mode, Maxim Durach, Anastasia Rusina
Department of Physics and Astronomy Faculty Publications
We propose an optical structure composed of two metal nanolayers enclosing a distributed Bragg reflector (DBR) mirror. The structure is an open photonic system whose bound modes are coupled to external radiation. We apply the special theoretical treatment based on inversion symmetry of the structure to classify its resonances. We show that the structure supports resonances transitional between Fabry-Pérot modes and Tamm plasmons. When the dielectric contrast of the DBR is removed these modes are a pair of conventional Fabry-Pérot resonances. They spectrally merge into a Tamm mode at high contrast. The optical properties of the structure in the frequency …
Approximate Mean-Field Equations Of Motion For Quasi-Two-Dimensional Bose-Einstein Condensates, Mark Edwards, Michael Krygier, Hadayat Seddiqi, Brandon Benton, Charles W. Clark
Approximate Mean-Field Equations Of Motion For Quasi-Two-Dimensional Bose-Einstein Condensates, Mark Edwards, Michael Krygier, Hadayat Seddiqi, Brandon Benton, Charles W. Clark
Department of Physics and Astronomy Faculty Publications
We present a method for approximating the solution of the three-dimensional, time-dependent Gross-Pitaevskii equation (GPE) for Bose-Einstein-condensate systems where the confinement in one dimension is much tighter than in the other two. This method employs a hybrid Lagrangian variational technique whose trial wave function is the product of a completely unspecified function of the coordinates in the plane of weak confinement and a Gaussian in the strongly confined direction having a time-dependent width and quadratic phase. The hybrid Lagrangian variational method produces equations of motion that consist of (1) a two-dimensional (2D) effective GPE whose nonlinear coefficient contains the width …
A Hemoglobin-Based Multifunctional Therapeutic: Polynitroxylated Pegylated Hemoglobin, Carleton C. J. Hsia, Li Ma
A Hemoglobin-Based Multifunctional Therapeutic: Polynitroxylated Pegylated Hemoglobin, Carleton C. J. Hsia, Li Ma
Department of Physics and Astronomy Faculty Publications
Polynitroxylated pegylated hemoglobin (PNPH) as a multifunctional therapeutic takes advantage of the ability of hemoglobin (Hb) to transport oxygen, the antioxidative stress activities from the redox coupling of nitroxide and heme iron, and the hypercolloid properties of pegylation. The published preclinical data demonstrating that PNPH acts as a neurovascular protective multifunctional therapeutic in an animal model simulating prehospital resuscitation of traumatic brain injury (TBI) with hemorrhagic shock (HS) are reviewed. Preliminary results on the potential utility of PNPH for neurovascular protection in thrombolytic stroke therapy and for correction of vascular dysfunction through transfusion in sickle-cell disease (SCD) are also discussed. …
Polynitroxyl Albumin And Albumin Therapy After Pediatric Asphyxial Cardia Arrest: Effects On Cerebral Blood Flow And Neurologic Outcome, Mioara D. Manole, Patrick M. Kochanek, Lesley M. Foley, T. Kevin Hitchens, Hülya Bayır, Henry Alexander, Robert Garman, Li Ma, Carleton J. C. Hsia, Chien Ho, Robert S. B. Clark
Polynitroxyl Albumin And Albumin Therapy After Pediatric Asphyxial Cardia Arrest: Effects On Cerebral Blood Flow And Neurologic Outcome, Mioara D. Manole, Patrick M. Kochanek, Lesley M. Foley, T. Kevin Hitchens, Hülya Bayır, Henry Alexander, Robert Garman, Li Ma, Carleton J. C. Hsia, Chien Ho, Robert S. B. Clark
Department of Physics and Astronomy Faculty Publications
Postresuscitation cerebral blood flow (CBF) disturbances and generation of reactive oxygen species likely contribute to impaired neurologic outcome after pediatric cardiac arrest (CA). Hence, we determined the effects of the antioxidant colloid polynitroxyl albumin (PNA) versus albumin or normal saline (NS) on CBF and neurologic outcome after asphyxial CA in immature rats. We induced asphyxia for 9 minutes in male and female postnatal day 16 to 18 rats randomized to receive PNA, albumin, or NS at resuscitation from CA or sham surgery. Regional CBF was measured serially from 5 to 150 minutes after resuscitation by arterial spin-labeled magnetic resonance imaging. …
A Ray Model Of Sound Focusing With A Balloon Lens: An Experiment For High School Students, Cleon Dean, Kendez Parker
A Ray Model Of Sound Focusing With A Balloon Lens: An Experiment For High School Students, Cleon Dean, Kendez Parker
Department of Physics and Astronomy Faculty Publications
A weather balloon filled with carbon dioxide gas is used as a positive spherical acoustic lens. High frequency but audible sound from a circular loudspeaker ensonifies the balloon and produces increased sound pressure levels in a region along the principal axis according to a ray acoustics model. This enhancement was measured experimentally and was found to agree with theory. The possibility that interference from reflected sound off walls or the floor could mask or mimic the expected focusing was countered by calculating and measuring within a “shadow zone” in which only direct rays or rays refracted by the balloon exist …
Metric Theory Of Gravity With Torsion In An Extra Dimension, Karthik H. Shankar, Anand Balaraman, Kameshwar C. Wali
Metric Theory Of Gravity With Torsion In An Extra Dimension, Karthik H. Shankar, Anand Balaraman, Kameshwar C. Wali
Department of Physics and Astronomy Faculty Publications
We consider a theory of gravity with a hidden extra dimension and metric-dependent torsion. A set of physically motivated constraints are imposed on the geometry so that the torsion stays confined to the extra dimension and the extra dimension stays hidden at the level of four-dimensional geodesic motion. At the kinematic level, the theory maps onto general relativity, but the dynamical field equations that follow from the action principle deviate markedly from the standard Einstein equations. We study static spherically symmetric vacuum solutions and homogeneous-isotropic cosmological solutions that emerge from the field equations. In both cases, we find solutions of …