Topologically Massive Gauge Theory: A Lorentzian Solution

We obtain a lorentzian solution for the topologically massive non-abelian gauge theory on AdS space by means of a SU(1, 1) gauge transformation of the previously found abelian solution. There exists a natural scale of length which is determined by the inverse topological mass. The topological mass is proportional to the square of the gauge coupling constant. In the topologically massive electrodynamics the field strength locally determines the gauge potential up to a closed 1-form via the (anti-)self-duality equation. We introduce a transformation of the gauge potential using the dual field strength which can be identified with an abelian gauge transformation. Then we present the map from the AdS space to the pseudo-sphere including the topological mass. This is the lorentzian analog of the Hopf map. This map yields a global decomposition of the AdS space as a trivial circle bundle over the upper portion of the pseudo-sphere which is the Hyperboloid model for the Lobachevski geometry. This leads to a reduction of the abelian field equation onto the pseudo-sphere using a global section of the solution on the AdS space. Then we discuss the integration of the field equation using the Archimedes map from the pseudo-sphere to the cylinder over the ideal Poincare circle. We also present a brief discussion of the holonomy of the gauge potential and the dual-field strength on the upper portion of the pseudo-sphere.Comment: 23 pages, 1 postscript figur

Covariant Hamiltonian Field Theory

A consistent, local coordinate formulation of covariant Hamiltonian field theory is presented. Whereas the covariant canonical field equations are equivalent to the Euler-Lagrange field equations, the covariant canonical transformation theory offers more general means for defining mappings that preserve the form of the field equations than the usual Lagrangian description. It is proved that Poisson brackets, Lagrange brackets, and canonical 2-forms exist that are invariant under canonical transformations of the fields. The technique to derive transformation rules for the fields from generating functions is demonstrated by means of various examples. In particular, it is shown that the infinitesimal canonical transformation furnishes the most general form of Noether's theorem. We furthermore specify the generating function of an infinitesimal space-time step that conforms to the field equations.Comment: 93 pages, no figure

Detecting Molecular Rotational Dynamics Complementing the Low-Frequency Terahertz Vibrations in a Zirconium-Based Metal-Organic Framework

We show clear experimental evidence of co-operative terahertz (THz) dynamics observed below 3 THz (~100 cm-1), for a low-symmetry Zr-based metal-organic framework (MOF) structure, termed MIL-140A [ZrO(O2C-C6H4-CO2)]. Utilizing a combination of high-resolution inelastic neutron scattering and synchrotron radiation far-infrared spectroscopy, we measured low-energy vibrations originating from the hindered rotations of organic linkers, whose energy barriers and detailed dynamics have been elucidated via ab initio density functional theory (DFT) calculations. For completeness, we obtained Raman spectra and characterized the alterations to the complex pore architecture caused by the THz rotations. We discovered an array of soft modes with trampoline-like motions, which could potentially be the source of anomalous mechanical phenomena, such as negative linear compressibility and negative thermal expansion. Our results also demonstrate coordinated shear dynamics (~2.5 THz), a mechanism which we have shown to destabilize MOF crystals, in the exact crystallographic direction of the minimum shear modulus (Gmin).Comment: 10 pages, 6 figure

The z<=0.1 Surface Brightness Distribution

The surface brightness distribution (SBD) function describes the number density of galaxies as measured against their central surface brightness. Because detecting galaxies with low central surface brightnesses is both time-consuming and complicated, determining the shape of this distribution function can be difficult. In a recent paper Cross, et al. suggested a bell-shaped SBD disk-galaxy function which peaks near the canonical Freeman value of 21.7 and then falls off significantly by 23.5 B mag arcsec-2. This is in contradiction to previous studies which have typically found flat (slope=0) SBD functions out to 24 - 25 B mag arcsec^-2 (the survey limits). Here we take advantage of a recent surface-brightness limited survey by Andreon & Cuillandre which reaches considerably fainter magnitudes than the Cross, et.al sample (M_B reaches fainter than -12 for Andreon & Cuillandre while the Cross, et.al sample is limited to M_B < -16) to re-evaluate both the SBD function as found by their data and the SBD for a wide variety of galaxy surveys, including the Cross, et al. data. The result is a SBD function with a flat slope out through the survey limits of 24.5 B mag arcsec^-2, with high confidence limits.Comment: 5 pages including 5 figures. accepted by A&A

Feather growth rate and mass in nearctic passerines with variablemigratory behavior and molt pattern

Bird species vary greatly in the duration of their annual complete feather molt. However, such variation is not well documented in birds from many biogeographic areas, which restricts our understanding of the diversification of molt strategies. Recent research has revealed that molt duration can be estimated in passerines from ptilochronology-based measurements of the growth rate of their tail feathers. We used this approach to explore how molt duration varied in 98 Nearctic species that have different migratory strategies and molt patterns. As previously documented for Palearctic species, migration was associated with a shortening of molt duration among species that molted during summer on their breeding range. However, molts of winter-molting migratory species were as long as those of summer-molting sedentary species, which suggests that winter molt also allows Nearctic migrants to avoid the temporal constraints experienced during summer. Our results also suggest that migratory species that undergo a stopover molt within the Mexican monsoon region have the shortest molt duration among all Nearctic passerines. Interestingly, and contrary to expectations from a potential tradeoff between molt duration and feather quality, observed variation in feather growth rate was positively correlated with differences in tail feather mass, which may be caused by differences among groups in the availability of resources for molting. We encourage the use of similar approaches to study the variation in molt duration in other geographic areas where knowledge of the evolution of molt is limited.

Interaction of Charged 3D Soliton with Coulomb Center

The Einstein - de Broglie particle-soliton concept is applied to simulate stationary states of an electron in a hydrogen atom. According to this concept, the electron is described by the localized regular solutions to some nonlinear equations. In the framework of Synge model for interacting scalar and electromagnetic fields a system of integral equations has been obtained, which describes the interaction between charged 3D soliton and Coulomb center. The asymptotic expressions for physical fields, describing soliton moving around the fixed Coulomb center, have been obtained with the help of integral equations. It is shown that the electron-soliton center travels along some stationary orbit around the Coulomb center. The electromagnetic radiation is absent as the Poynting vector has non-wave asymptote $O(r^{-3})$ after averaging over angles, i.e. the existence of spherical surface corresponding to null Poynting vector stream, has been proved. Vector lines for Poynting vector are constructed in asymptotical area.Comment: LaTeX ,12 page

Treatment of Porphyromonas gulae infection and downstream pathology in the aged dog by lysine-gingipain inhibitor COR388.

COR388, a small-molecule lysine-gingipain inhibitor, is currently being investigated in a Phase 2/3 clinical trial for Alzheimer's disease (AD) with exploratory endpoints in periodontal disease. Gingipains are produced by two species of bacteria, Porphyromonas gingivalis and Porphyromonas gulae, typically associated with periodontal disease and systemic infections in humans and dogs, respectively. P. gulae infection in dogs is associated with periodontal disease, which provides a physiologically relevant model to investigate the pharmacology of COR388. In the current study, aged dogs with a natural oral infection of P. gulae and periodontal disease were treated with COR388 by oral administration for up to 90 days to assess lysine-gingipain target engagement and reduction of bacterial load and downstream pathology. In a 28-day dose-response study, COR388 inhibited the lysine-gingipain target and reduced P. gulae load in saliva, buccal cells, and gingival crevicular fluid. The lowest effective dose was continued for 90 days and was efficacious in continuous reduction of bacterial load and downstream periodontal disease pathology. In a separate histology study, dog brain tissue showed evidence of P. gulae DNA and neuronal lysine-gingipain, demonstrating that P. gulae infection is systemic and spreads beyond its oral reservoir, similar to recent observations of P. gingivalis in humans. Together, the pharmacokinetics and pharmacodynamics of COR388 lysine-gingipain inhibition, along with reduction of bacterial load and periodontal disease in naturally occurring P. gulae infection in the dog, support the use of COR388 in targeting lysine-gingipain and eliminating P. gingivalis infection in humans

Deep Near-IR Surface Photometry of 57 Galaxies in the Local Sphere of Influence

We present H-band surface photometry of 57 galaxies drawn from the Local Sphere of Influence (LSI) with distances of less than 10 Mpc from the Milky Way. The images with a typical surface brightness limit 4 mag fainter than 2MASS (24.5 mag arcsec^-2 < sb_lim < 26 mag arcsec ^-2) have been obtained with IRIS2 on the 3.9 m Anglo-Australian Telescope. A total of 22 galaxies that remained previously undetected in the near-IR and potentially could have been genuinely young galaxies were found to have an old stellar population with a star density 1-2 magnitudes below the 2MASS detection threshold. The cleaned near-IR images reveal the morphology and extent of many of the galaxies for the first time. For all program galaxies, we derive radial luminosity profiles, ellipticities, and position angles, together with global parameters such as total magnitude, mean effective surface brightness and half-light radius. Our results show that 2MASS underestimates the total magnitude of galaxies with _eff between 18-21 mag arcsec^-2 by up to 2.5 mag. The Sersic parameters best describing the observed surface brightness profiles are also presented. Adopting accurate galaxy distances and a H-band mass-to-light ratio of Upsilon_H=1.0 +/- 0.4, the LSI galaxies are found to cover a stellar mass range of 5.6 < log_10 (M_stars) < 11.1. The results are discussed along with previously obtained optical data. Our sample of low luminosity galaxies is found to follow closely the optical-infrared B versus H luminosity relation defined by brighter galaxies with a slope of 1.14 +/- 0.02 and scatter of 0.3 magnitudes. Finally we analyse the luminosity - surface brightness relation to determine an empirical mass-to-light ratio of Upsilon_H=0.78 +/- 0.08 for late-type galaxies in the H-band.Comment: Accepted by AJ. High resolution version available at http://www.mso.anu.edu.au/~emma/KirbyHband.pd

Ultraviolet Detection of the Binary Companion to the Type IIb SN 2001ig

We present HST/WFC3 ultraviolet imaging in the F275W and F336W bands of the Type IIb SN 2001ig at an age of more than 14 years. A clear point source is detected at the site of the explosion having $m_{\rm F275W}=25.39 \pm 0.10$ and $m_{\rm F336W}=25.88 \pm 0.13$ mag. Despite weak constraints on both the distance to the host galaxy NGC 7424 and the line-of-sight reddening to the supernova, this source matches the characteristics of an early B-type main sequence star having $19,000 < T_{\rm eff} < 22,000$ K and $\log (L_{\rm bol}/L_{\odot})=3.92 \pm 0.14$. A BPASS v2.1 binary evolution model, with primary and secondary masses of 13 M$_{\odot}$ and 9 M$_{\odot}$ respectively, is found to resemble simultaneously in the Hertzsprung-Russell diagram both the observed location of this surviving companion, and the primary star evolutionary endpoints for other Type IIb supernovae. This same model exhibits highly variable late-stage mass loss, as expected from the behavior of the radio light curves. A Gemini/GMOS optical spectrum at an age of 6 years reveals a narrow He II emission line, indicative of continuing interaction with a dense circumstellar medium at large radii from the progenitor. We review our findings on SN 2001ig in the context of binary evolution channels for stripped-envelope supernovae. Owing to the uncrowded nature of its environment in the ultraviolet, this study of SN 2001ig represents one of the cleanest detections to date of a surviving binary companion to a Type IIb supernova.Comment: 8 pages, 3 figures. Resubmitted to ApJ after minor changes requested by refere