A new species of Dialeurodes Cockerell (Hemiptera: Aleyrodidae) on Schefflera Forst and Forst in Florida

Descriptions of pupal cases of Dialeurodes schefflerae, new species, as well as distribution records are presented. This species is known to occur in Florida, Hawaii and Puerto Rico appearing to feed only on species of Schefflera Forst and Forst. This restriction to plant hosts in the Asian genus Schefflera, along with its affinities with Dialeurodes agalmae Takahashi, Dialeurodes citri (Ashmead) and Dialeurodes kirkaldyi (Kotinsky), suggests it is an invasive species, probably endemic to the Asian region

Magnetometry of random AC magnetic fields using a single Nitrogen-Vacancy center

We report on the use of a single NV center to probe fluctuating AC magnetic fields. Using engineered currents to induce random changes in the field amplitude and phase, we show that stochastic fluctuations reduce the NV center sensitivity and, in general, make the NV response field-dependent. We also introduce two modalities to determine the field spectral composition, unknown a priori in a practical application. One strategy capitalizes on the generation of AC-field-induced coherence 'revivals', while the other approach uses the time-tagged fluorescence intensity record from successive NV observations to reconstruct the AC field spectral density. These studies are relevant for magnetic sensing in scenarios where the field of interest has a non-trivial, stochastic behavior, such as sensing unpolarized nuclear spin ensembles at low static magnetic fields.Comment: 11 pages, 3 figure

Structure and clumping in the fast wind of NGC6543

Far-UV spectroscopy from the FUSE satellite is analysed to uniquely probe spatial structure and clumping in the fast wind of the central star of the H-rich planetary nebula NGC6543 (HD164963). Time-series data of the unsaturated PV 1118, 1128 resonance line P Cygni profiles provide a very sensitive diagnostic of variable wind conditions in the outflow. We report on the discovery of episodic and recurrent optical depth enhancements in the PV absorption troughs, with some evidence for a 0.17-day modulation time-scale. SEI line-synthesis modelling is used to derive physical properties, including the optical depth evolution of individual `events'. The characteristics of these features are essentially identical to the `discrete absorption components' (DACs) commonly seen in the UV lines of massive OB stars. We have also employed the unified model atmosphere code CMFGEN to explore spectroscopic signatures of clumping, and report in particular on the clear sensitivity of the PV lines to the clump volume filling factor. The results presented here have implications for the downward revision of mass-loss rates in PN central stars. We conclude that the temporal structures seen in the PV lines of NGC6543 likely have a physical origin that is similar to that operating in massive, luminous stars, and may be related to near-surface perturbations caused by stellar pulsation and/or magnetic fields.Comment: 11 pages, 11 figures. Accepted for publication in MNRA

Lunar Outgassing, Transient Phenomena and The Return to The Moon, I: Existing Data

Herein the transient lunar phenomena (TLP) report database is subjected to a discriminating statistical filter robust against sites of spurious reports, and produces a restricted sample that may be largely reliable. This subset is highly correlated geographically with the catalog of outgassing events seen by the Apollo 15, 16 and Lunar Prospector alpha-particle spectrometers for episodic Rn-222 gas release. Both this robust TLP sample and even the larger, unfiltered sample are highly correlated with the boundary between mare and highlands, as are both deep and shallow moonquakes, as well as Po-210, a long-lived product of Rn-222 decay and a further tracer of outgassing. This offers another significant correlation relating TLPs and outgassing, and may tie some of this activity to sagging mare basalt plains (perhaps mascons). Additionally, low-level but likely significant TLP activity is connected to recent, major impact craters (while moonquakes are not), which may indicate the effects of cracks caused by the impacts, or perhaps avalanches, allowing release of gas. The majority of TLP (and Rn-222) activity, however, is confined to one site that produced much of the basalt in the Procellarum Terrane, and it seems plausible that this TLP activity may be tied to residual outgassing from the formerly largest volcanic ffusion sites from the deep lunar interior. With the coming in the next few years of robotic spacecraft followed by human exploration, the study of TLPs and outgassing is both promising and imperiled. We will have an unprecedented pportunity to study lunar outgassing, but will also deal with a greater burden of anthropogenic lunar gas than ever produced. There is a pressing need to study lunar atmosphere and its sources while still pristine. [Abstract abridged.]Comment: 35 pages, 3 figures, submitted to Icarus. Other papers in series found at http://www.astro.columbia.edu/~arlin/TLP

Experimental Implementation of Logical Bell State Encoding

Liquid phase NMR is a general purpose test-bed for developing methods of coherent control relevant to quantum information processing. Here we extend these studies to the coherent control of logical qubits and in particular to the unitary gates necessary to create entanglement between logical qubits. We report an experimental implementation of a conditional logical gate between two logical qubits that are each in decoherence free subspaces that protect the quantum information from fully correlated dephasing.Comment: 9 Pages, 5 Figure

Beyond deficiency:Potential benefits of increased intakesof vitamin K for bone and vascular health

Vitamin K is wellknown for its role in the synthesisof a number of blood coagulationfactors.During recent years vitaminK-dependent proteins werediscovered to be of vital importancefor bone and vascular health.Recommendations for dietary vitaminK intake have been made onthe basis of the hepatic requirementsfor the synthesis of bloodcoagulation factors.Accumulatingevidence suggests that the requirementsfor other functions thanblood coagulation may be higher.This paper is the result of a closedworkshop (Paris,November 2002)in which a number of Europeanvitamin K experts reviewed theavailable data and formulated theirstandpoint with respect to recommendeddietary vitamin K intakeand the use of vitamin K-containingsupplements

Switchable lasing in coupled multimode microcavities

We propose the new concept of a switchable multimode microlaser. As a generic, realistic model of a multimode microresonator a system of two coupled defects in a two-dimensional photonic crystal is considered. We demonstrate theoretically that lasing of the cavity into one selected resonator mode can be caused by injecting an appropriate optical pulse at the onset of laser action (injection seeding). Temporal mode-to-mode switching by re-seeding the cavity after a short cool-down period is demonstrated by direct numerical solution. A qualitative analytical explanation of the mode switching in terms of the laser bistability is presented.Comment: Accepted for publication in Physical Review Letters. Published, somewhat shortened versio

Fidelity enhancement by logical qubit encoding

We demonstrate coherent control of two logical qubits encoded in a decoherence free subspace (DFS) of four dipolar-coupled protons in an NMR quantum information processor. A pseudo-pure fiducial state is created in the DFS, and a unitary logical qubit entangling operator evolves the system to a logical Bell state. The four-spin molecule is partially aligned by a liquid crystal solvent, which introduces strong dipolar couplings among the spins. Although the system Hamiltonian is never fully specified, we demonstrate high fidelity control over the logical degrees of freedom. In fact, the DFS encoding leads to higher fidelity control than is available in the full four-spin Hilbert space.Comment: 10 pages, 2 figure

Species Richness, Distribution, and Relative Abundance of Freshwater Mussels (Bivalvia: Unionidae) of the Buffalo National River, Arkansas

The Buffalo River in north-central Arkansas is approximately 246 km long and flows through the Boston Mountains and Springfield and Salem Plateaus to the White River near Buffalo City. The Buffalo River is America’s first National River with the National Park Service owning 11% of land in the watershed. The objectives of this project were to survey the entire perennially wet length of river, search for mussels of conservation concern, and document the freshwater mussel assemblages. During 2004 and 2005, 235 km of the river were qualitatively and quantitatively surveyed. We documented 64 mussel assemblages. Time constrained qualitatively sampled assemblages (n=41) resulted in a mean richness of 7.8 with a range of 2 to 12 species. Quantitatively sampled mussel assemblages (n=23) had a mean richness of 9.5, ranging from 4 to 16 species and a mean density of 6.9 individuals/m2 , ranging from 1.3 to 25.6 individuals/m2 . Detrended correspondence analysis revealed 4 distinct community types dominated by: 1) Ptychobranchus occidentalis (Conrad 1836), 2) Villosa iris (Lea 1829), 3) Cyclonaias tuberculata (Rafinesque 1820), and 4) Actinonaias ligamentina (Lamarck 1819) that represented approximate species gradients along the river’s length. Previous surveys collectively recorded a total of 26 species for the river, however; only 23 species were identified in this survey with no federally listed threatened or endangered species found. The Buffalo National River has a moderately diverse and abundant native freshwater mussel fauna. Seventy-eight percent of the current species are considered to be of conservation concern (S1-S3). Consequently, the Buffalo National River may prove to be an important refuge for a declining mussel resource