Spatial imaging of Zn and other elements in Huanglongbing-affected grapefruit by synchrotron-based micro X-ray fluorescence investigation

Huanglongbing (HLB) is a highly destructive, fast-spreading disease of citrus, causing substantial economic losses to the citrus industry worldwide. Nutrient levels and their cellular distribution patterns in stems and leaves of grapefruit were analysed after graft-inoculation with lemon scions containing 'Candidatus Liberibacter asiaticus' (Las), the heat-tolerant Asian type of the HLB bacterium. After 12 months, affected plants showed typical HLB symptoms and significantly reduced Zn concentrations in leaves. Micro-XRF imaging of Zn and other nutrients showed that preferential localization of Zn to phloem tissues was observed in the stems and leaves collected from healthy grapefruit plants, but was absent from HLB-affected samples. Quantitative analysis by using standard references revealed that Zn concentration in the phloem of veins in healthy leaves was more than 10 times higher than that in HLB-affected leaves. No significant variation was observed in the distribution patterns of other elements such as Ca in stems and leaves of grapefruit plants with or without graft-inoculation of infected lemon scions. These results suggest that reduced phloem transport of Zn is an important factor contributing to HLB-induced Zn deficiency in grapefruit. Our report provides the first in situ, cellular level visualization of elemental variations within the tissues of HLB-affected citrus. © 2014 © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology

Orbital approach to microstate free entropy

Motivated by Voiculescu's liberation theory, we introduce the orbital free entropy $\chi_orb$ for non-commutative self-adjoint random variables (also for "hyperfinite random multi-variables"). Besides its basic properties the relation of $\chi_orb$ with the usual free entropy $\chi$ is shown. Moreover, the dimension counterpart $\delta_{0,orb}$ of $\chi_orb$ is discussed, and we obtain the relation of $\delta_{0,orb}$ with the original free entropy dimension $\delta_0$ with applications to $\delta_0$ itself.Comment: 38 pages; Section 5 was largely improved and Section 6 was adde

Management of pediatric radiation dose using Philips fluoroscopy systems DoseWise: perfect image, perfect sense

Although image quality (IQ) is the ultimate goal for accurate diagnosis and treatment, minimizing radiation dose is equally important. This is especially true when pediatric patients are examined, because their sensitivity to radiation-induced cancer is two to three times greater than that of adults. DoseWise is an ALARA-based philosophy within Philips Medical Systems that is active at every level of product design. It encompasses a set of techniques, programs and practices that ensures optimal IQ while protecting people in the X-ray environments. DoseWise methods include management of the X-ray beam, less radiation-on time and more dose information for the operator. Smart beam management provides automatic customization of the X-ray beam spectrum, shape, and pulse frequency. The Philips-patented grid-controlled fluoroscopy (GCF) provides grid switching of the X-ray beam in the X-ray tube instead of the traditional generator switching method. In the examination of pediatric patients, DoseWise technology has been scientifically documented to reduce radiation dose to <10% of the dose of traditional continuous fluoroscopy systems. The result is improved IQ at a significantly lower effective dose, which contributes to the safety of patients and staff

Regular Poisson structures on massive non-rotating BTZ black holes

We revisit the non-rotating massive BTZ black hole within a pseudo-Riemannian symmetric space context. Using classical symmetric space techniques we find that every such space intrinsically carries a regular Poisson structure whose symplectic leaves are para-hermitian symmetric surfaces. We also obtain a global expression of the metric yielding a dynamical description of the black hole from its initial to its final singularity.Comment: LaTex, 18 pages, 3 figures, version published in Nucl. Phys.

The Fefferman-Graham Ambiguity and AdS Black Holes

Asymptotically anti-de Sitter space-times in pure gravity with negative cosmological constant are described, in all space-time dimensions greater than two, by classical degrees of freedom on the conformal boundary at space-like infinity. Their effective boundary action has a conformal anomaly for even dimensions and is conformally invariant for odd ones. These degrees of freedom are encoded in traceless tensor fields in the Fefferman-Graham asymptotic metric for any choice of conformally flat boundary and generate all Schwarzschild and Kerr black holes in anti-de Sitter space-time. We argue that these fields describe components of an energy-momentum tensor of a boundary theory and show explicitly how this is realized in 2+1 dimensions. There, the Fefferman-Graham fields reduce to the generators of the Virasoro algebra and give the mass and the angular momentum of the BTZ black holes. Their local expression is the Liouville field in a general curved background.Comment: Latex, 14 pages; one reference modified, minor misprints correcte

It is not all about being sweet: differences in floral traits and insect visitation among hybrid carrot cultivars

Cytoplasmically male-sterile (CMS) carrot cultivars suffer from low pollination rates. In this study, insect visitation varied more than eightfold between 17 CMS carrot cultivars in a field-based cultivar evaluation trial. The visitation rates of honey bees, nectar scarabs, muscoid flies, and wasps each significantly differed among these cultivars. No significant difference in visitation rates was observed among cultivars of different CMS type (brown-anther or petaloid) or flower colour, but cultivars of Berlicumer root type had significantly higher insect visitation rates than Nantes. Six cultivars were further compared in regard to selected umbel traits: as umbel diameter increased, so did the visitation of soldier beetles, while that of honey bees decreased. Finally, nectar of these six cultivars was analysed for sugar content, which revealed monosaccharides to be the most common sugars in all. There was high variation in the levels of sugars from individual umbellets but no significant difference in nectar sugar composition among cultivars, suggesting that nectar sugar composition is of minor importance regarding pollinator attraction to hybrid CMS carrot umbels

Non-Linear Vibrations in Nuclei

We have perfomed Time Dependant Hartree-Fock (TDHF) calculations on the non linear response of nuclei. We have shown that quadrupole (and dipole) motion produces monopole (and quadrupole) oscillations in all atomic nuclei. We have shown that these findings can be interpreted as a large coupling between one and two phonon states leading to large anharmonicities.Comment: 4 pages, 3 figure

Non-hermitian Exact Local Bosonic Algorithm for Dynamical Quarks

We present an exact version of the local bosonic algorithm for the simulation of dynamical quarks in lattice QCD. This version is based on a non-hermitian polynomial approximation of the inverse of the quark matrix. A Metropolis test corrects the systematic errors. Two variants of this test are presented. For both of them, a formal proof is given that this Monte Carlo algorithm converges to the right distribution. Simulation data are presented for different lattice parameters. The dynamics of the algorithm and its scaling in lattice volume and quark mass are investigated.Comment: 32 pages, LaTex, 8 ps figure

Systematic study of autocorrelation time in pure SU(3) lattice gauge theory

Results of our autocorrelation measurement performed on Fujitsu AP1000 are reported. We analyze (i) typical autocorrelation time, (ii) optimal mixing ratio between overrelaxation and pseudo-heatbath and (iii) critical behavior of autocorrelation time around cross-over region with high statistic in wide range of $\beta$ for pure SU(3) lattice gauge theory on $8^4$, $16^4$ and $32^4$ lattices. For the mixing ratio K, small value (3-7) looks optimal in the confined region, and reduces the integrated autocorrelation time by a factor 2-4 compared to the pseudo-heatbath. On the other hand in the deconfined phase, correlation times are short, and overrelaxation does not seem to matter For a fixed value of K(=9 in this paper), the dynamical exponent of overrelaxation is consistent with 2 Autocorrelation measurement of the topological charge on $32^3 \times 64$ lattice at $\beta$ = 6.0 is also briefly mentioned.Comment: 3 pages of A4 format including 7-figure