Winterfat, saltbush – forage shrubs for the Canadian prairies

Non-Peer Reviewe

Bacterial viability and biological seed treatment of canola

Non-Peer ReviewedThe use of sulfur-oxidizing plant growth promoting rhizobacteria (PGPR) applied as seed treatment for increasing canola yield has been reported previously (Kloepper et al., 1988; Yesmin and Banerjee, 2000). For consistent plant growth response colonization of the rhizosphere and rhizoplane by the PGPR is essential. In many cases, however, results have been variable or not comparable. Inadequate colonization of the roots by the introduced PGPR strain is considered to be a major reason for sub-optimal results (Schippers et al., 1995). Bacterial viability is one of the most important factors for successful and adequate colonization of the rhizosphere and rhizoplane that ultimately affect the plant yield. Thus, the ability of microbial inoculants to successfully colonize expanding root systems is of major importance in determining the potential success of the biological seed treatments (Parke, 1991). Seed is used as a carrier for inoculum and biologicals should be in a state where it can most effectively colonize the emerging roots. Biological activity, however, may decline rapidly between the time of inoculation and seeding to field. The present study investigates the survivals of PGPR on biologically treated seeds with non-coated (bare), peat coated and fungicide-coated seeds. Mixture of PGPR strains were also examined as that might have greater potential to give a consistent performance under different environmental and growth conditions

Comparison of inoculant media for sulfur-oxidizing plant growth promoting rhizobacteria in canola

Non-Peer ReviewedThe ability of rhizosphere microorganisms to influence plant growth is gaining considerable attention worldwide. Various studies have already proven the beneficial effect of plant growth promoting rhizobacteria (PGPR) on different agricultural crops (Kloepper, 1993; Banerjee, 1995). Canola, like other oil seed crop has high sulfur demand. In recent years, several attempts have been made to utilize S-oxidizing microorganisms to meet plant S requirement and to substitute costly S fertilizer. But the success is variable, as the information on S-oxidizing PGPR is limited and the mechanisms also not yet fully understood. In many cases, no standard methods were followed and different inoculation media were used. The population density and activities of microorganisms could vary with the inoculation media. The aim of the present study was to compare the effects of PGPR if any due to the difference in the commonly used inoculant media like seed, soil and elemental S fertilizer

Noncommuting Electric Fields and Algebraic Consistency in Noncommutative Gauge theories

We show that noncommuting electric fields occur naturally in $\theta$-expanded noncommutative gauge theories. Using this noncommutativity, which is field dependent, and a hamiltonian generalisation of the Seiberg-Witten Map, the algebraic consistency in the lagrangian and hamiltonian formulations of these theories, is established. A comparison of results in different descriptions shows that this generalised map acts as canonical transformation in the physical subspace only. Finally, we apply the hamiltonian formulation to derive the gauge symmetries of the action.Comment: 16 pages, LaTex, considerably expanded version with a new section on `Gauge symmetries'; To appear in Phys. Rev.

Radiation Damage of F8 Lead Glass with 20 MeV Electrons

Using a 20 MeV linear accelerator, we investigate the effects of electromagnetic radiation on the optical transparency of F8 lead glass. Specifically, we measure the change in attenuation length as a function of radiation dose. Comparing our results to similar work that utilized a proton beam, we conclude that F8 lead glass is more susceptible to proton damage than electron damage.Comment: 5 pages, 6 figure

Measurement of Magnetic Relaxation in the peak regime of V3Si

Magnetization relaxation measurements are carried out in the Peak effect regime of superconducting V3Si crystal, using Quantum Design SQUID magnetometer. Relaxation in the increasing field scan is logarithmic in time, consistent with the theory of flux creep. The relaxation on the decreasing field scan however exhibits athermal behavior which is predominantly governed by the flux avalanches triggered by the small external field perturbation experienced by the superconductor during measurement scan in an inhomogeneous field.Comment: PDF, 17 pages including 9 figure

Meson-Baryon-Baryon Vertex Function and the Ward-Takahashi Identity

Ohta proposed a solution for the well-known difficulty of satisfying the Ward-Takahashi identity for a photo-meson-baryon-baryon amplitude ($\gamma$MBB) when a dressed meson-baryon-baryon (MBB) vertex function is present. He obtained a form for the $\gamma$MBB amplitude which contained, in addition to the usual pole terms, longitudinal seagull terms which were determined entirely by the MBB vertex function. He arrived at his result by using a Lagrangian which yields the MBB vertex function at tree level. We show that such a Lagrangian can be neither hermitian nor charge conjugation invariant. We have been able to reproduce Ohta's result for the $\gamma$MBB amplitude using the Ward-Takahashi identity and no other assumption, dynamical or otherwise, and the most general form for the MBB and $\gamma$MBB vertices. However, contrary to Ohta's finding, we find that the seagull terms are not robust. The seagull terms extracted from the $\gamma$MBB vertex occur unchanged in tree graphs, such as in an exchange current amplitude. But the seagull terms which appear in a loop graph, as in the calculation of an electromagnetic form factor, are, in general, different. The whole procedure says nothing about the transverse part of the ($\gamma$MBB) vertex and its contributions to the amplitudes in question.Comment: A 20 pages Latex file and 16 Postscript figures in an uuencoded format. Use epsf.sty to include the figures into the Latex fil

Entropy spectrum of a Kerr anti-de Sitter black hole

The entropy spectrum of a spherically symmetric black hole was derived without the quasinormal modes in the work of Majhi and Vagenas. Extending this work to rotating black holes, we quantize the entropy and the horizon area of a Kerr anti-de Sitter black hole by two methods. The spectra of entropy and area are obtained via the Bohr-Sommerfeld quantization rule and the adiabatic invariance in the first way. By addressing the wave function of emitted (absorbed) particles, the entropy and the area are quantized in the second one. Both results show that the entropy and the area spectra are equally spaced.Comment: Accepted for publication in The European Physical Journal C, Volume 72, Issue

Black Hole Entropy: From Shannon to Bekenstein

In this note we have applied directly the Shannon formula for information theory entropy to derive the Black Hole (Bekenstein-Hawking) entropy. Our analysis is semi-classical in nature since we use the (recently proposed [8]) quantum mechanical near horizon mode functions to compute the tunneling probability that goes in to the Shannon formula, following the general idea of [5]. Our framework conforms to the information theoretic origin of Black Hole entropy, as originally proposed by Bekenstein.Comment: 9 pages Latex, Comments are welcome; Thoroughly revised version, reference and acknowledgements sections enlarged, numerical error in final result corrected, no major changes, to appear in IJT

Interacting Ricci Dark Energy with Logarithmic Correction

Motivated by the holographic principle, it has been suggested that the dark energy density may be inversely proportional to the area $A$ of the event horizon of the universe. However, such a model would have a causality problem. In this work, we consider the entropy-corrected version of the holographic dark energy model in the non-flat FRW universe and we propose to replace the future event horizon area with the inverse of the Ricci scalar curvature. We obtain the equation of state (EoS) parameter $\omega_{\Lambda}$, the deceleration parameter $q$ and $\Omega_D'$ in the presence of interaction between Dark Energy (DE) and Dark Matter (DM). Moreover, we reconstruct the potential and the dynamics of the tachyon, K-essence, dilaton and quintessence scalar field models according to the evolutionary behavior of the interacting entropy-corrected holographic dark energy model.Comment: 24 pages, accepted for publication in 'Astrophysics and Space Science, DOI:10.1007/s10509-012-1031-8