Partial characterization of a Pasteuria sp. attacking the citrus nematode, Tylenchulus semipenetrans, in Florida

Des juvéniles et des mâles du nématode des citrus, #Tylenchulus semipenetrans, infestés par #Pasteuria sp. ont été détectés dans des échantillons de sol de vergers de citrus de la partie centrale de la Floride. Au cours d'essais au laboratoire, il a été observé que trois à seize endospores s'attachent à la cuticule du nématode. Des endospores mûres sont présentes à l'intérieur du nématode 18 jours après l'attache des endospores. Le développement du parasite est asynchrone, dépendant du spécimen du nématode. Chez les mâles, la région du corps contenant les spermatocytes n'est pas colonisée. Les juvéniles de deuxième stade et les mâles infestés contiennent de 320 à 400 endospores (18 jours après l'attache des endospores, à 25 °C). Les femelles ne sont pas parasitées et aucune endospore n'a été détectée sur leur cuticule. Les endospores de #Pasteuria sp. ne s'attachent pas à la cuticule de #Meloidogyne incognita, M. javanica, Radopholus citrophilus ou #R. similis$. (Résumé d'auteur

Classical stability of U(1)_A domain walls in dense matter QCD

It was recently shown that there exists metastable U(1)_A domain wall configurations in high-density QCD (\mu >> 1 GeV). In the following we will assess the stability of such non-trivial field configurations at intermediate densities (\mu < 1 GeV). The existence of such configurations at intermediate densities could have interesting consequences for the physics of neutron stars with high core density.Comment: 13 pages, 2 Postscript figures, typos correcte

Global Strings in High Density QCD

We show that several types of global strings occur in colour superconducting quark matter due to the spontaneous violation of relevant U(1) symmetries. These include the baryon U(1)_B, and approximate axial U(1)_A symmetries as well as an approximate U(1)_S arising from kaon condensation. We discuss some general properties of these strings and their interactions. In particular, we demonstrate that the U(1)_A strings behave as superconducting strings. We draw some parallels between these strings and global cosmological strings and discuss some possible implications of these strings to the physics in neutron star cores.Comment: LaTeX JHEP-format (26 pages) Option in source for REVTeX4 forma

Drum vortons in high density QCD

Recently it was shown that high density QCD supports of number of topological defects. In particular, there are U(1)_Y strings that arise due to K^0 condensation that occurs when the strange quark mass is relatively large. The unique feature of these strings is that they possess a nonzero K^+ condensate that is trapped on the core. In the following we will show that these strings (with nontrivial core structure) can form closed loops with conserved charge and currents trapped on the string worldsheet. The presence of conserved charges allows these topological defects, called vortons, to carry angular momentum, which makes them classically stable objects. We also give arguments demonstrating that vortons carry angular momentum very efficiently (in terms of energy per unit angular momentum) such that they might be the important degrees of freedom in the cores of neutron stars.Comment: 11 pages, accepted for publication in Physical Review

Charge Neutrality of the Color-Flavor Locked Phase from the Low Energy Effective Theory

We investigate the issue of charge neutrality of the CFL$K^0$ phase of dense quark matter using the low energy effective theory of high density QCD. We show that the local electric and color charge neutrality of the ground state in a homogeneous color superconducting medium follows from its dynamics. We also consider the situation of a spatially inhomogeneous medium, such as may be found in a neutron star core. We find that spatial inhomogeneity results in the generation of electric fields, and positrons/electrons may be present in the ground state. We estimate the concentration of charged leptons in the ground state to be $n_{e}\sim{10^2}{cm}^{-3}$ and consider their influence on the opacity of the medium with respect to the modified photons.Comment: typos corrected, this version to appear in PR