Efficient generation of graph states for quantum computation

We present an entanglement generation scheme which allows arbitrary graph states to be efficiently created in a linear quantum register via an auxiliary entangling bus. The dynamics of the entangling bus is described by an effective non-interacting fermionic system undergoing mirror-inversion in which qubits, encoded as local fermionic modes, become entangled purely by Fermi statistics. We discuss a possible implementation using two species of neutral atoms stored in an optical lattice and find that the scheme is realistic in its requirements even in the presence of noise.Comment: 4 pages, 3 figures, RevTex 4; v2 - Major changes and new result

Exact solution for the energy density inside a one-dimensional non-static cavity with an arbitrary initial field state

We study the exact solution for the energy density of a real massless scalar field in a two-dimensional spacetime, inside a non-static cavity with an arbitrary initial field state, taking into account the Neumann and Dirichlet boundary conditions. This work generalizes the exact solution proposed by Cole and Schieve in the context of the Dirichlet boundary condition and vacuum as the initial state. We investigate diagonal states, examining the vacuum and thermal field as particular cases. We also study non-diagonal initial field states, taking as examples the coherent and Schrodinger cat states.Comment: 10 pages, 8 figure

Toward in vitro fertilization in Brachiaria spp.

Brachiaria are forage grasses widely cultivated in tropical areas. In vitro pollination was applied to accessions of Brachiaria spp. by placing pollen of non-dehiscent anthers on a solid medium near isolated ovaries. Viability and in vitro germination were tested in order to establish good conditions for pollen development. Comparing sexual to apomictic plants, apomictic pollen has more abortion after meiosis during the microspore stage and a lower viability and, of both types, only some plants have sufficient germination in a high sugar concentration. Using in vitro pollination with the sexual plant, the pollen tube penetrates into the nucellus and micropyle, but the embryo sac degenerates and collapses. In the apomictic B. decumbens, in vitro pollination leads to the transfer of the sperm nuclei into the egg cell and the central cell. The results are discussed according to normal fertilization and barriers in sexual and apomictic plants

Near-infrared Observations of the Proto-Planetary Nebula IRAS~07131-0147

We have obtained near-infrared imaging and an optical spectrum of the proto-planetary nebula IRAS~07131-0147, a highly polarized bipolar reflection nebula believed to be in evolutionary transition from the asymptotic giant branch to the planetary nebula phase. Our images reveal point reflection symmetry in the lobes - a relatively rare morphological feature. We place an upper limit on the distance of 6.5 kpc. Utilizing numerical integrations of single grain scattering models we find the nebula to lie at an inclination angle of i=20\pm5 degrees in the plane of the sky. We present a refined geometric interpretation of IRAS~07131-0147 consistent with our new observational data and argue that the central star is likely to have an as yet undetected binary companion.Comment: 16 pages, compressed uuencoded file includes 6 postscript figures, also available via anonymous ftp at ftp://igpp.llnl.gov/pub/alves/; accepted for publication in the Astronomical Journa

Severe Pelvic Malformations in Caudal Regression Syndrome

info:eu-repo/semantics/publishedVersio