Wind tunnel studies of circulation control elliptical airfoils

Effects of blown jets on the lift and drag of cambered elliptical airfoils are described. Performance changes due to a splitter plate attached to the lower surface of an elliptical airfoil near the trailing edge with and without blowing are indicated. Lift and drag characteristics of airfoils with two blown jets are compared with airfoils with single blowing jets. Airfoil designs that vary the location of a second jet relative to a fixed jet are described

Expression of Sindbis virus structural proteins via recombinant vaccinia virus: synthesis, processing, and incorporation into mature Sindbis virions

We have obtained a vaccinia virus recombinant which contains a complete cDNA copy of the 26S RNA of Sindbis virus within the thymidine kinase gene of the vaccinia virus genome. This recombinant constitutively transcribed the Sindbis sequences throughout the infectious cycle, reflecting the dual early-late vaccinia promoter used in this construction. The Sindbis-derived transcripts were translationally active, giving rise to both precursor and mature structural proteins of Sindbis virus, including the capsid protein (C), the precursor of glycoprotein E2 (PE2), and the two mature envelope glycoproteins (E1 and E2). These are the same products translated from the 26S mRNA during Sindbis infection, and thus these proteins were apparently cleaved, glycosylated, and transported in a manner analogous to that seen during authentic Sindbis infections. By using epitope-specific antibodies, it was possible to demonstrate that recombinant-derived proteins were incorporated into Sindbis virions during coinfections with monoclonal antibody-resistant Sindbis variants. These results suggest that all the information necessary to specify the proper biogenesis of Sindbis virus structural proteins resides within the 26S sequences and that vaccinia may provide an appropriate system for using DNA molecular genetic manipulations to unravel a variety of questions pertinent to RNA virus replication

Neomycin resistance as a dominant selectable marker for selection and isolation of vaccinia virus recombinants

The antibiotic G418 was shown to be an effective inhibitor of vaccinia virus replication when an appropriate concentration of it was added to cell monolayers 48 h before infection. Genetic engineering techniques were used in concert with DNA transfection protocols to construct vaccinia virus recombinants containing the neomycin resistance gene (neo) from transposon Tn5. These recombinants contained the neo gene linked in either the correct or incorrect orientation relative to the vaccinia virus 7.5-kilodalton gene promoter which is expressed constitutively throughout the course of infection. The vaccinia virus recombinant containing the chimeric neo gene in the proper orientation was able to grow and form plaques in the presence of G418, whereas both the wild-type and the recombinant virus with the neo gene in the opposite polarity were inhibited by more than 98%. The effect of G418 on virus growth may be mediated at least in part by selective inhibition of the synthesis of a subset of late viral proteins. These results are discussed with reference to using this system, the conferral of resistance to G418 with neo as a positive selectable marker, to facilitate constructing vaccinia virus recombinants which contain foreign genes of interest

Zero-mode contribution to the light-front Hamiltonian of Yukawa type models

Light-front Hamiltonian for Yukawa type models is determined without the framework of canonical light-front formalism. Special attention is given to the contribution of zero modes.Comment: 14 pages, Latex, revised version with minor changes, Submitted to J.Phys.

Calculation of the Mass Spectrum of QED-2 in Light-Front Coordinates

With the aim of a further investigation of the nonperturbative Hamiltonian approach in gauge field theories, the mass spectrum of QED-2 is calculated numerically by using the corrected Hamiltonian that was constructed previously for this theory on the light front. The calculations are performed for a wide range of the ratio of the fermion mass to the fermion charge at all values of the parameter \hat\theta related to the vacuum angle \theta. The results obtained in this way are compared with the results of known numerical calculations on a lattice in Lorentz coordinates. A method is proposed for extrapolating the values obtained within the infrared-regularized theory to the limit where the regularization is removed. The resulting spectrum agrees well with the known results in the case of \theta=0; in the case of \theta=\pi, there is agreement at small values of the fermion mass (below the phase-transition point).Comment: LaTex 2.09, 20 pages, 7 figures. New improved expression for the effective LF Hamiltonian was adde

Pauli-Villars Regularization in nonperturbative Hamiltonian approach on the Light Front

The advantage of Pauli-Villars regularization in quantum field theory quantized on the light front is explained. Simple examples of scalar $\lambda\varphi^4$ field theory and Yukawa-type model are used. We give also an example of nonperturbative calculation in the theory with Pauli-Villars fields, using for that a model of anharmonic oscillator modified by inclusion of ghost variables playing the role similar to Pauli-Villars fields.Comment: LaTeX, 10 pages, 2 figures. Article will be published in AIP Conference Proceedings, the final publication will be available at http://scitation.aip.org/content/aip/proceeding/aipc

Graphene-like optical light field and its interaction with two-level atoms

The theoretical basis leading to the creation of a light field with a hexagonal honeycomb structure resembling graphene is considered along with its experimental realization and its interaction with atoms. It is argued that associated with such a light field is an optical dipole potential which leads to the diffraction of the atoms, but the details depend on whether the transverse spread of the atomic wave packet is larger than the transverse dimensions of the optical lattice (resonant Kapitza-Dirac effect) or smaller (optical Stern-Gerlach effect). Another effect in this context involves the creation of gauge fields due to the Berry phase acquired by the atom moving in the light field. The experimental realization of the light field with a honeycomb hexagonal structure is described using holographic methods and we proceed to explore the atom diffraction in the Kapitza-Dirac regime as well as the optical Stern-Gerlach regime, leading to momentum distributions with characteristic but different hexagonal structures. The artificial gauge fields too are shown to have the same hexagonal spatial structure and their magnitude can be significantly large. The effects are discussed with reference to typical parameters for the atoms and the fields

Quantum Fields on the Light Front, Formulation in Coordinates close to the Light Front, Lattice Approximation

We review the fundamental ideas of quantizing a theory on a Light Front including the Hamiltonian approach to the problem of bound states on the Light Front and the limiting transition from formulating a theory in Lorentzian coordinates (where the quantization occurs on spacelike hyperplanes) to the theory on the Light Front, which demonstrates the equivalence of these variants of the theory. We describe attempts to find such a form of the limiting transition for gauge theories on the Wilson lattice.Comment: LaTeX 2e, 14 page

Canonical formulation of the embedded theory of gravity equivalent to Einstein's General Relativity

We study the approach in which independent variables describing gravity are functions of the space-time embedding into a flat space of higher dimension. We formulate a canonical formalism for such a theory in a form, which requires imposing additional constraints, which are a part of Einstein's equations. As a result, we obtain a theory with an eight-parameter gauge symmetry. This theory becomes equivalent to Einstein's general relativity either after partial gauge fixing or after rewriting the metric in the form that is invariant under the additional gauge transformations. We write the action for such a theory.Comment: LaTeX, 17 page