Scientists at the University of Rochester and the J. Craig Venter Institute have discovered a copy of the entire genome of Wolbachia, a bacterial parasite, residing inside the genome of its completely different host species Drosophila Ananassae, the fruitfly. To isolate the fly’s genome from the parasite’s, the flies were fed with a simple antibiotic, killing the Wolbachia, but Wolbachia genes were still there. The scientists found that the genes were residing directly inside the second chromosome of the insect, and that some of these genes are even transcribed in uninfected flies, so that copies of the gene sequence are made in cells that could be used to make Wolbachia proteins.

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Physicists from the University of Texas at Austin found that “a liquid jet can bounce off a bath of the same liquid if the bath is moving horizontally with respect to the jet. Previous observations of jets rebounding off a bath (e.g. Kaye effect) have been reported only for non-Newtonian fluids, while we observe bouncing jets in a variety of Newtonian fluids, including mineral oil poured by hand. A thin layer of air separates the bouncing jet from the bath, and the relative motion replenishes the film of air. Jets with one or two bounces are stable for a range of viscosity, jet flow rate and velocity, and bath velocity. The bouncing phenomenon exhibits hysteresis and multiple steady states”.¹

1. M. Thrasher, S. Jung, Y. Kwong Pang, C. Chuu, H. L. Swinney, “The Bouncing Jet: A Newtonian Liquid Rebounding off a Free Surface“, arXiv:0707.1721v1 [physics.flu-dyn] (2007). [↩]

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From ACQAO through The Quantum Pontiff: “Theorists from the UQ (Ashton Bradley, Simon Haine, Murray Olsen) and ANU Faculties (Joseph Hope) nodes of the ARC Centre of Excellence for Quantum-Atom Optics (ACQAO) have come up with a scheme to teleport quantum states of collections of atoms from one position to another by converting the quantum state to light and back again. The scheme relies on the sender and receiver each having a reservoir of extremely cold atoms, known as a Bose-Einstein condensate [and] it gets around the need for the sender and receiver to share entanglement, as the quantum state to be teleported is never actually measured“.¹

1. A. S. Bradley, M. K. Olsen, S. A. Haine, J. J. Hope, “Teleportation of massive particles without shared entanglement“, arXiv:0706.0062v1 [quant-ph] (2007). [↩]

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From PhysicsWeb News: “The existence of a hypothetical particle called the axion has been put into further doubt now that the team that first claimed its discovery has failed to reproduce their results. Physicists working on the PVLAS experiment in Italy say that the tiny rotation in the polarization of laser light that they reported last year does not support the existence of axions, but rather is an artifact related to how the experiment had been performed”¹.

1. E. Zavattini et al., “New PVLAS results and limits on magnetically induced optical rotation and ellipticity in vacuum“, arXiv:0706.3419v1 (2007) [↩]

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From PhysicsWeb News: “A physicist in the US has analysed radio waves from distant galaxies to obtain a new upper bound on the electrical charge of the photon. Brett Altschul of Indiana University has found that the charge is no more than 10^-46 times the charge of the electron — assuming the existence of photons with positive and negative charges. This is 13 orders of magnitude better than the previous direct bound on the charge of a particle that we normally assume to be neutral”¹.

1. Phys. Rev. Lett. 98 261801 [↩]

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