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228 results on '"Toomey, L."'

51. Comparison of ion channel inhibitor combinations for limiting secondary degeneration following partial optic nerve transection

Author

Toomey, L., Bartlett, C., Majimbi, Maimuna, Gopalasingam, G., Rodger, J., Fitzgerald, Melinda, Toomey, L., Bartlett, C., Majimbi, Maimuna, Gopalasingam, G., Rodger, J., and Fitzgerald, Melinda

Abstract

Following neurotrauma, secondary degeneration of neurons and glia adjacent to the injury leads to further functional loss. A combination of ion channel inhibitors (lomerizine + oxATP + YM872) has been shown to be effective at limiting structural and functional loss due to secondary degeneration. Here we assess efficacy of the combination where oxATP is replaced with Brilliant Blue G (BBG), a more clinically applicable P2X7 receptor inhibitor. Partial optic nerve transection was used to model secondary degeneration in adult female rats. Animals were treated with combinations of lomerizine + YM872 + oxATP or lomerizine + YM872 + BBG, delivered via osmotic mini-pump directly to the injury site. Outcomes assessed were Iba1 + and ED1 + microglia and macrophages, oligodendroglial cell numbers, node/paranode structure and visual function using the optokinetic nystagmus test. The lomerizine + BBG + YM872 combination was at least as effective at the tested concentrations as the lomerizine + oxATP + YM872 combination at preserving node/paranode structure and visual function when delivered locally. However, neither ion channel inhibitor combination significantly improved microglial/macrophage nor oligodendroglial numbers compared to vehicle-treated controls. In conclusion, a locally delivered combination of ion channel inhibitors incorporating lomerizine + BBG + YM872 is at least as effective at limiting secondary degeneration following partial injury to the optic nerve as the combination incorporating oxATP.

Published
2018

52. Comparison of pulsar positions from timing and very long baseline astrometry

Author

Wang, J., Coles, W., Hobbs, G., Shannon, Ryan, Manchester, R., Kerr, M., Yuan, J., Wang, N., Bailes, M., Bhat, N., Dai, S., Dempsey, J., Keith, M., Lasky, P., Levin, Y., Oslowski, S., Ravi, V., Reardon, D., Rosado, P., Russell, C., Spiewak, R., van Straten, W., Toomey, L., Wen, L., You, X., Zhu, X., Wang, J., Coles, W., Hobbs, G., Shannon, Ryan, Manchester, R., Kerr, M., Yuan, J., Wang, N., Bailes, M., Bhat, N., Dai, S., Dempsey, J., Keith, M., Lasky, P., Levin, Y., Oslowski, S., Ravi, V., Reardon, D., Rosado, P., Russell, C., Spiewak, R., van Straten, W., Toomey, L., Wen, L., You, X., and Zhu, X.

Published
2017

53. Wide-band profile domain pulsar timing analysis

Author

Lentati, L., Kerr, M., Dai, S., Hobson, M., Shannon, Ryan, Hobbs, G., Bailes, M., Ramesh Bhat, N., Burke-Spolaor, S., Coles, W., Dempsey, J., Lasky, P., Levin, Y., Manchester, R., Oslowski, S., Ravi, V., Reardon, D., Rosado, P., Spiewak, R., van Straten, W., Toomey, L., Wang, J., Wen, L., You, X., Zhu, X., Lentati, L., Kerr, M., Dai, S., Hobson, M., Shannon, Ryan, Hobbs, G., Bailes, M., Ramesh Bhat, N., Burke-Spolaor, S., Coles, W., Dempsey, J., Lasky, P., Levin, Y., Manchester, R., Oslowski, S., Ravi, V., Reardon, D., Rosado, P., Spiewak, R., van Straten, W., Toomey, L., Wang, J., Wen, L., You, X., and Zhu, X.

Abstract

We extend profile domain pulsar timing to incorporate wide-band effects such as frequencydependent profile evolution and broad-band shape variation in the pulse profile. We also incorporate models for temporal variations in both pulse width and in the separation in phase of the main pulse and interpulse. We perform the analysis with both nested sampling and Hamiltonian Monte Carlo methods. In the latter case, we introduce a new parametrization of the posterior that is extremely efficient in the low signal-to-noise regime and can be readily applied to a wide range of scientific problems. We apply this methodology to a series of simulations, and to between seven and nine years of observations for PSRs J1713+0747, J1744-1134 and J1909-3744 with frequency coverage that spans 700-3600 Mhz. We use a smooth model for profile evolution across the full frequency range, and compare smooth and piecewise models for the temporal variations in dispersion measure (DM). We find that the profile domain framework consistently results in improved timing precision compared to the standard analysis paradigm by as much as 40 per cent for timing parameters. Incorporating smoothness in the DM variations into the model further improves timing precision by as much as 30 per cent. For PSR J1713+0747, we also detect pulse shape variation uncorrelated between epochs, which we attribute to variation intrinsic to the pulsar at a level consistent with previously published analyses. Not accounting for this shape variation biases the measured arrival times at the level of ~30 ns, the same order of magnitude as the expected shift due to gravitational waves in the pulsar timing band.

Published
2017

54. Gravitational-Wave Cosmology across 29 Decades in Frequency

Author

Lasky, P., Mingarelli, C., Smith, T., Giblin, J., Thrane, E., Reardon, D., Caldwell, R., Bailes, M., Bhat, N., Burke-Spolaor, S., Dai, S., Dempsey, J., Hobbs, G., Kerr, M., Levin, Y., Manchester, R., Oslowski, S., Ravi, V., Rosado, P., Shannon, Ryan, Spiewak, R., van Straten, W., Toomey, L., Wang, J., Wen, L., You, X., Zhu, X., Lasky, P., Mingarelli, C., Smith, T., Giblin, J., Thrane, E., Reardon, D., Caldwell, R., Bailes, M., Bhat, N., Burke-Spolaor, S., Dai, S., Dempsey, J., Hobbs, G., Kerr, M., Levin, Y., Manchester, R., Oslowski, S., Ravi, V., Rosado, P., Shannon, Ryan, Spiewak, R., van Straten, W., Toomey, L., Wang, J., Wen, L., You, X., and Zhu, X.

Published
2016

55. Timing analysis for 20 millisecond pulsars in the Parkes Pulsar Timing Array

Author

Swinburne University of Technology. Faculty of Science, Engineering and Technology Centre for Astrophysics & Supercomputing, Reardon, D. J., Hobbs, G., Coles, W., Levin, Y., Keith, M. J., Bailes, M., Bhat, N. D. R., Burke-Spolaor, S., Dai, S., Kerr, M., Lasky, P. D., Manchester, R. N., Oslowski, S., Ravi, V., Shannon, R. M., van Straten, W., Toomey, L., Wang, J., Wen, L., You, X. P., Zhu, X. J., Swinburne University of Technology. Faculty of Science, Engineering and Technology Centre for Astrophysics & Supercomputing, Reardon, D. J., Hobbs, G., Coles, W., Levin, Y., Keith, M. J., Bailes, M., Bhat, N. D. R., Burke-Spolaor, S., Dai, S., Kerr, M., Lasky, P. D., Manchester, R. N., Oslowski, S., Ravi, V., Shannon, R. M., van Straten, W., Toomey, L., Wang, J., Wen, L., You, X. P., and Zhu, X. J.

Abstract

We present timing models for 20 millisecond pulsars in the Parkes Pulsar Timing Array. The precision of the parameter measurements in these models has been improved over earlier results by using longer data sets and modelling the non-stationary noise. We describe a new noise modelling procedure and demonstrate its effectiveness using simulated data. Our methodology includes the addition of annual dispersion measure (DM) variations to the timing models of some pulsars. We present the first significant parallax measurements for PSRs J1024-0719, J1045-4509, J1600-3053, J1603-7202, and J1730-2304, as well as the first significant measurements of some post-Keplerian orbital parameters in six binary pulsars, caused by kinematic effects. Improved Shapiro delay measurements have resulted in much improved pulsar mass measurements, particularly for PSRs J0437-4715 and J1909-3744 with M-p = 1.44 +/- 0.07 and 1.47 +/- 0.03 M-circle dot, respectively. The improved orbital period-derivative measurement for PSR J0437-4715 results in a derived distance measurement at the 0.16 per cent level of precision, D = 156.79 +/- 0.25 pc, one of the most fractionally precise distance measurements of any star to date.

Published
2016

56. Responses of the arcto-boreal krill species Thysanoessa inermis to variations in water temperature: coupling Hsp70 isoform expressions with metabolism

Author

Huenerlage, Kim, Cascella, Kévin, Corre, E., Toomey, L., Lee, C.Y., Buchholz, Friedrich, Toullec, Jean-Yves, Huenerlage, Kim, Cascella, Kévin, Corre, E., Toomey, L., Lee, C.Y., Buchholz, Friedrich, and Toullec, Jean-Yves

Abstract

Recent studies have indicated a metabolic temperature sensitivity in both the arcto-boreal krill species Thysanoessa inermis and Thysanoessa raschii that may determine these species' abundance and population persistence at lower latitudes (up to 40° N). T. inermis currently dominates the krill community in the Barents Sea and in the high Arctic Kongsfjord. We aimed to increase the knowledge on the upper thermal limit found in the latter species by estimating the CT50 value (19.7 °C) (critical temperature at which 50 % of animals are reactive) and by linking metabolic rate measurements with molecular approaches. Optical oxygen sensors were used to measure respiration rates in steps of 2 °C (from 0 to 16 °C). To follow the temperature-mediated mechanisms of passive response, i.e., as a proxy for molecular stress, molecular chaperone heat shock protein 70 (Hsp70) sequences were extracted from a transcriptome assembly, and the gene expression kinetics were monitored during an acute temperature exposure to 6 or 10 °C with subsequent recovery at 4 °C. Our results showed upregulation of hsp70 genes, especially the structurally constitutive and mitochondrial isoforms. These findings confirmed the temperature sensitivity of T. inermis and showed that the thermal stress took place before reaching the upper temperature limit estimated by respirometry at 12 °C. This study provides a baseline for further investigations into the thermal tolerances of arcto-boreal Thysanoessa spp. and comparisons with other krill species under different climatic regimes, especially Antarctica.

Published
2016

57. Genetic structure of Patagonian toothfish populations from otolith DNA

Author

Toomey, L., Welsford, D., Appleyard, S., Polanowski, A., Faux, C., Deagle, B., Belchier, M., Marthick, J., Jarman, Simon, Toomey, L., Welsford, D., Appleyard, S., Polanowski, A., Faux, C., Deagle, B., Belchier, M., Marthick, J., and Jarman, Simon

Abstract

© Antarctic Science Ltd 2016. The Patagonian toothfish, Dissostichus eleginoides, is a valuable fishery species and has a discontinuous distribution across the Southern Ocean. Identification of the genetic stock structure of toothfish would allow evaluation of the suitability of the spatial scale at which fisheries management operates. Genetic subdivision seems likely given the species distribution. Population genetics studies of this species have been performed; however, they have been limited by sample size, spatial coverage and/or the type of markers investigated. As a potential solution, we developed methods for extracting toothfish DNA from otoliths that are available in large numbers from collections held at several research institutes. Genetic differentiation between the three oceanic sectors was investigated. Four mitochondrial and four nuclear markers with multiple single nucleotide polymorphisms were sequenced by high throughput sequencing for samples from six locations. Genetic differentiation was found between three sectors with nuclear markers. However, only the Pacific sector was differentiated from other sectors with mitochondrial markers. This study demonstrates the usefulness of otolith DNA as a means of increasing sample sizes for population genetics research of fish. Additionally, the combination of nuclear and mitochondrial markers may allow insight into how the observed differences in movements between male and female toothfish impact population structure.

Published
2016

58. Timing analysis for 20 millisecond pulsars in the Parkes Pulsar Timing Array

Author

Reardon, D., Hobbs, G., Coles, W., Levin, Y., Keith, M., Bailes, M., Bhat, Ramesh, Burke-Spolaor, S., Dai, S., Kerr, M., Lasky, P., Manchester, R., Oslowski, S., Ravi, V., Shannon, Ryan, van Straten, W., Toomey, L., Wang, J., Wen, L., You, X., Zhu, X., Reardon, D., Hobbs, G., Coles, W., Levin, Y., Keith, M., Bailes, M., Bhat, Ramesh, Burke-Spolaor, S., Dai, S., Kerr, M., Lasky, P., Manchester, R., Oslowski, S., Ravi, V., Shannon, Ryan, van Straten, W., Toomey, L., Wang, J., Wen, L., You, X., and Zhu, X.

Abstract

We present timing models for 20 millisecond pulsars in the Parkes Pulsar Timing Array. The precision of the parameter measurements in these models has been improved over earlier results by using longer data sets and modelling the non-stationary noise. We describe a new noise modelling procedure and demonstrate its effectiveness using simulated data. Our methodology includes the addition of annual dispersion measure (DM) variations to the timing models of some pulsars. We present the first significant parallax measurements for PSRs J1024−0719, J1045−4509, J1600−3053, J1603−7202, and J1730−2304, as well as the first significant measurements of some post-Keplerian orbital parameters in six binary pulsars, caused by kinematic effects. Improved Shapiro delay measurements have resulted in much improved pulsar mass measurements, particularly for PSRs J0437−4715 and J1909−3744 with Mp = 1.44 ± 0.07 and 1.47 ± 0.03 M⊙, respectively. The improved orbital period-derivative measurement for PSR J0437−4715 results in a derived distance measurement at the 0.16 per cent level of precision, D = 156.79 ± 0.25 pc, one of the most fractionally precise distance measurements of any star to date.

Published
2016

59. The disturbance of a millisecond pulsar magnetosphere

Author

Shannon, Ryan, Lentati, L., Kerr, M., Bailes, M., Bhat, N., Coles, W., Dai, S., Dempsey, J., Hobbs, G., Keith, M., Lasky, P., Levin, Y., Manchester, R., Oslowski, S., Ravi, V., Reardon, D., Rosado, P., Spiewak, R., Van Straten, W., Toomey, L., Wang, J., Wen, L., You, X., Zhu, X., Shannon, Ryan, Lentati, L., Kerr, M., Bailes, M., Bhat, N., Coles, W., Dai, S., Dempsey, J., Hobbs, G., Keith, M., Lasky, P., Levin, Y., Manchester, R., Oslowski, S., Ravi, V., Reardon, D., Rosado, P., Spiewak, R., Van Straten, W., Toomey, L., Wang, J., Wen, L., You, X., and Zhu, X.

Abstract

Pulsar timing has enabled some of the strongest tests of fundamental physics. Central to the technique is the assumption that the detected radio pulses can be used to accurately measure the rotation of the pulsar. Here, we report on a broadband variation in the pulse profile of the millisecond pulsar J1643−1224. A new component of emission suddenly appears in the pulse profile, decays over four months, and results in a permanently modified pulse shape. Profile variations such as these may be the origin of timing noise observed in other millisecond pulsars. The sensitivity of pulsar-timing observations to gravitational radiation can be increased by accounting for this variability.

Published
2016

60. Versatile directional searches for gravitational waves with Pulsar Timing Arrays

Author

Madison, D., Zhu, X., Hobbs, G., Coles, W., Shannon, Ryan, Wang, J., Tiburzi, C., Manchester, R., Bailes, M., Bhat, Ramesh, Burke-Spolaor, S., Dai, S., Dempsey, J., Keith, M., Kerr, M., Lasky, P., Levin, Y., Oslowski, S., Ravi, V., Reardon, D., Rosado, P., Spiewak, R., van Straten, W., Toomey, L., Wen, L., You, X., Madison, D., Zhu, X., Hobbs, G., Coles, W., Shannon, Ryan, Wang, J., Tiburzi, C., Manchester, R., Bailes, M., Bhat, Ramesh, Burke-Spolaor, S., Dai, S., Dempsey, J., Keith, M., Kerr, M., Lasky, P., Levin, Y., Oslowski, S., Ravi, V., Reardon, D., Rosado, P., Spiewak, R., van Straten, W., Toomey, L., Wen, L., and You, X.

Abstract

By regularly monitoring the most stable millisecond pulsars over many years, pulsar timing arrays (PTAs) are positioned to detect and study correlations in the timing behaviour of those pulsars. Gravitational waves (GWs) from supermassive black hole binaries (SMBHBs) are an exciting potentially detectable source of such correlations. We describe a straightforward technique by which a PTA can be ‘phased-up’ to form time series of the two polarization modes of GWs coming from a particular direction of the sky. Our technique requires no assumptions regarding the time-domain behaviour of a GW signal. This method has already been used to place stringent bounds on GWs from individual SMBHBs in circular orbits. Here, we describe the methodology and demonstrate the versatility of the technique in searches for a wide variety of GW signals including bursts with unmodelled waveforms. Using the first six years of data from the Parkes Pulsar Timing Array, we conduct an all-sky search for a detectable excess of GW power from any direction. For the lines of sight to several nearby massive galaxy clusters, we carry out a more detailed search for GW bursts with memory, which are distinct signatures of SMBHB mergers. In all cases, we find that the data are consistent with noise.

Published
2016

61. Wide-band profile domain pulsar timing analysis

Author

Lentati, L., primary, Kerr, M., additional, Dai, S., additional, Hobson, M. P., additional, Shannon, R. M., additional, Hobbs, G., additional, Bailes, M., additional, Bhat, N. D. Ramesh, additional, Burke-Spolaor, S., additional, Coles, W., additional, Dempsey, J., additional, Lasky, P. D., additional, Levin, Y., additional, Manchester, R. N., additional, Osłowski, S., additional, Ravi, V., additional, Reardon, D. J., additional, Rosado, P. A., additional, Spiewak, R., additional, van Straten, W., additional, Toomey, L., additional, Wang, J., additional, Wen, L., additional, You, X., additional, and Zhu, X., additional

Published
2016
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62. The International Pulsar Timing Array: First data release

Author

Verbiest, J. P. W., primary, Lentati, L., additional, Hobbs, G., additional, van Haasteren, R., additional, Demorest, P. B., additional, Janssen, G. H., additional, Wang, J.-B., additional, Desvignes, G., additional, Caballero, R. N., additional, Keith, M. J., additional, Champion, D. J., additional, Arzoumanian, Z., additional, Babak, S., additional, Bassa, C. G., additional, Bhat, N. D. R., additional, Brazier, A., additional, Brem, P., additional, Burgay, M., additional, Burke-Spolaor, S., additional, Chamberlin, S. J., additional, Chatterjee, S., additional, Christy, B., additional, Cognard, I., additional, Cordes, J. M., additional, Dai, S., additional, Dolch, T., additional, Ellis, J. A., additional, Ferdman, R. D., additional, Fonseca, E., additional, Gair, J. R., additional, Garver-Daniels, N. E., additional, Gentile, P., additional, Gonzalez, M. E., additional, Graikou, E., additional, Guillemot, L., additional, Hessels, J. W. T., additional, Jones, G., additional, Karuppusamy, R., additional, Kerr, M., additional, Kramer, M., additional, Lam, M. T., additional, Lasky, P. D., additional, Lassus, A., additional, Lazarus, P., additional, Lazio, T. J. W., additional, Lee, K. J., additional, Levin, L., additional, Liu, K., additional, Lynch, R. S., additional, Lyne, A. G., additional, Mckee, J., additional, McLaughlin, M. A., additional, McWilliams, S. T., additional, Madison, D. R., additional, Manchester, R. N., additional, Mingarelli, C. M. F., additional, Nice, D. J., additional, Osłowski, S., additional, Palliyaguru, N. T., additional, Pennucci, T. T., additional, Perera, B. B. P., additional, Perrodin, D., additional, Possenti, A., additional, Petiteau, A., additional, Ransom, S. M., additional, Reardon, D., additional, Rosado, P. A., additional, Sanidas, S. A., additional, Sesana, A., additional, Shaifullah, G., additional, Shannon, R. M., additional, Siemens, X., additional, Simon, J., additional, Smits, R., additional, Spiewak, R., additional, Stairs, I. H., additional, Stappers, B. W., additional, Stinebring, D. R., additional, Stovall, K., additional, Swiggum, J. K., additional, Taylor, S. R., additional, Theureau, G., additional, Tiburzi, C., additional, Toomey, L., additional, Vallisneri, M., additional, van Straten, W., additional, Vecchio, A., additional, Wang, Y., additional, Wen, L., additional, You, X. P., additional, Zhu, W. W., additional, and Zhu, X.-J., additional

Published
2016
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63. A study of multifrequency polarization pulse profiles of millisecond pulsars

Author

Dai, S., Hobbs, G., Manchester, R., Kerr, M., Shannon, Ryan, van Straten, W., Mata, A., Bailes, M., Bhat, N., Burke-Spolaor, S., Coles, W., Johnston, S., Keith, M., Levin, Y., Oslowski, S., Reardon, D., Ravi, V., Sarkissian, J., Tiburzi, C., Toomey, L., Wang, H., Wang, J., Wen, L., Xu, R., Yan, W., Zhu, X., Dai, S., Hobbs, G., Manchester, R., Kerr, M., Shannon, Ryan, van Straten, W., Mata, A., Bailes, M., Bhat, N., Burke-Spolaor, S., Coles, W., Johnston, S., Keith, M., Levin, Y., Oslowski, S., Reardon, D., Ravi, V., Sarkissian, J., Tiburzi, C., Toomey, L., Wang, H., Wang, J., Wen, L., Xu, R., Yan, W., and Zhu, X.

Published
2015

64. Gravitational waves from binary supermassive black holes missing in pulsar observations

Author

Shannon, Ryan, Ravi, V., Lentati, L., Lasky, P., Hobbs, G., Kerr, M., Manchester, R., Coles, W., Levin, Y., Bailes, M., Bhat, N., Burke-Spolaor, S., Dai, S., Keith, M., Oslowski, S., Reardon, D., Van Strateni, W., Toomey, L., Wang, J., Wen, L., Wyithe, J., Zhu, X., Shannon, Ryan, Ravi, V., Lentati, L., Lasky, P., Hobbs, G., Kerr, M., Manchester, R., Coles, W., Levin, Y., Bailes, M., Bhat, N., Burke-Spolaor, S., Dai, S., Keith, M., Oslowski, S., Reardon, D., Van Strateni, W., Toomey, L., Wang, J., Wen, L., Wyithe, J., and Zhu, X.

Abstract

Gravitational waves are expected to be radiated by supermassive black hole binaries formed during galaxy mergers. A stochastic superposition of gravitational waves from all such binary systems would modulate the arrival times of pulses from radio pulsars. Using observations of millisecond pulsars obtained with the Parkes radio telescope, we constrained the characteristic amplitude of this background, Acyr, to be <1.0 × 10-15 with 95% confidence.This limit excludes predicted ranges for Acyr from current models with 91 to 99.7% probability. We conclude that binary evolution is either stalled or dramatically accelerated by galactic-center environments and that higher-cadence and shorterwavelength observations would be more sensitive to gravitational waves.

Published
2015

65. Pulsar observations of extreme scattering events

Author

Coles, W., Kerr, M., Shannon, Ryan, Hobbs, G., Manchester, R., You, X., Bailes, M., Bhat, N., Burke-Spolaor, S., Dai, S., Keith, M., Levin, Y., Oslowski, S., Ravi, V., Reardon, D., Toomey, L., Straten, W., Wang, J., Wen, L., Zhu, X., Coles, W., Kerr, M., Shannon, Ryan, Hobbs, G., Manchester, R., You, X., Bailes, M., Bhat, N., Burke-Spolaor, S., Dai, S., Keith, M., Levin, Y., Oslowski, S., Ravi, V., Reardon, D., Toomey, L., Straten, W., Wang, J., Wen, L., and Zhu, X.

Abstract

Extreme scattering events (ESEs) in the interstellar medium (ISM) were first observed in regular flux measurements of compact extragalactic sources. They are characterized by a flux variation over a period of weeks, suggesting the passage of a "diverging plasma lens" across the line of sight (LOS). Modeling the refraction of such a lens indicates that the structure size must be of the order of AU and the electron density of the order of 10s of cm−3. Similar structures have been observed in measurements of pulsar intensity scintillation and group delay. Here we report observations of two ESEs, showing increases in both intensity scintillation and dispersion made with the Parkes Pulsar Timing Array. These allow us to make more complete models of the ESE, including an estimate of the "outer-scale" of the turbulence in the plasma lens. These observations clearly show that the ESE structure is fully turbulent on an AU scale. They provide some support for the idea that the structures are extended along the LOS, such as would be the case for a scattering shell. The dispersion measurements also show a variety of AU scale structures that would not be called ESEs, yet involve electron density variations typical of ESEs and likely have the same origin.

Published
2015

66. Searching for gravitational wave memory bursts with the Parkes Pulsar Timing Array

Author

Wang, J., Hobbs, G., Coles, W., Shannon, Ryan, Zhu, X., Madison, D., Kerr, M., Ravi, V., Keith, M., Manchester, R., Levin, Y., Bailes, M., Bhat, N., Burke-Spolaor, S., Dai, S., Oslowski, S., van Straten, W., Toomey, L., Wang, N., Wen, L., Wang, J., Hobbs, G., Coles, W., Shannon, Ryan, Zhu, X., Madison, D., Kerr, M., Ravi, V., Keith, M., Manchester, R., Levin, Y., Bailes, M., Bhat, N., Burke-Spolaor, S., Dai, S., Oslowski, S., van Straten, W., Toomey, L., Wang, N., and Wen, L.

Abstract

Anisotropic bursts of gravitational radiation produced by events such as supermassive black hole mergers leave permanent imprints on space. Such gravitational wave ‘memory’ (GWM) signals are, in principle, detectable through pulsar timing as sudden changes in the apparent pulse frequency of a pulsar. If an array of pulsars is monitored as a GWM signal passes over the Earth, the pulsars would simultaneously appear to change pulse frequency by an amount that varies with their sky position in a quadrupolar fashion. Here, we describe a search algorithm for such events and apply the algorithm to approximately six years of data from the Parkes Pulsar Timing Array. We find no GWM events and set an upper bound on the rate for events which could have been detected. We show, using simple models of black hole coalescence rates, that this non-detection is not unexpected.

Published
2015

67. Versatile directional searches for gravitational waves with Pulsar Timing Arrays

Author

Madison, D. R., primary, Zhu, X.-J., additional, Hobbs, G., additional, Coles, W., additional, Shannon, R. M., additional, Wang, J. B., additional, Tiburzi, C., additional, Manchester, R. N., additional, Bailes, M., additional, Bhat, N. D. R., additional, Burke-Spolaor, S., additional, Dai, S., additional, Dempsey, J., additional, Keith, M., additional, Kerr, M., additional, Lasky, P., additional, Levin, Y., additional, Osłowski, S., additional, Ravi, V., additional, Reardon, D., additional, Rosado, P., additional, Spiewak, R., additional, van Straten, W., additional, Toomey, L., additional, Wen, L., additional, and You, X., additional

Published
2015
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68. Timing analysis for 20 millisecond pulsars in the Parkes Pulsar Timing Array

Author

Reardon, D. J., primary, Hobbs, G., additional, Coles, W., additional, Levin, Y., additional, Keith, M. J., additional, Bailes, M., additional, Bhat, N. D. R., additional, Burke-Spolaor, S., additional, Dai, S., additional, Kerr, M., additional, Lasky, P. D., additional, Manchester, R. N., additional, Osłowski, S., additional, Ravi, V., additional, Shannon, R. M., additional, van Straten, W., additional, Toomey, L., additional, Wang, J., additional, Wen, L., additional, You, X. P., additional, and Zhu, X.-J., additional

Published
2015
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70. An all-sky search for continuous gravitational waves in the parkes pulsar timing array data set

Author

Zhu, XJ, Zhu, XJ, Hobbs, G, Wen, L, Coles, WA, Wang, JB, Shannon, RM, Manchester, RN, Bailes, M, Bhat, NDR, Burke-Spolaor, S, Dai, S, Keith, MJ, Kerr, M, Levin, Y, Madison, DR, Osłowski, S, Ravi, V, Toomey, L, Van Straten, W, Zhu, XJ, Zhu, XJ, Hobbs, G, Wen, L, Coles, WA, Wang, JB, Shannon, RM, Manchester, RN, Bailes, M, Bhat, NDR, Burke-Spolaor, S, Dai, S, Keith, MJ, Kerr, M, Levin, Y, Madison, DR, Osłowski, S, Ravi, V, Toomey, L, and Van Straten, W

Abstract

We present results of an all-sky search in the Parkes Pulsar Timing Array (PPTA) Data Release 1 data set for continuous gravitational waves (GWs) in the frequency range from 5 × 10-9 to 2 × 10-7 Hz. Such signals could be produced by individual supermassive binary black hole systems in the early stage of coalescence.We phase up the pulsar timing array data set to form, for each position on the sky, two data streams that correspond to the twoGWpolarizations and then carry out an optimal search for GW signals on these data streams. Since no statistically significant GWs were detected, we place upper limits on the intrinsic GW strain amplitude h0 for a range of GW frequencies. For example, at 10-8 Hz our analysis has excluded with 95 per cent confidence the presence of signals with h0 ≥ 1.7 × 10-14. Our new limits are about a factor of 4 more stringent than those of Yardley et al. based on an earlier PPTA data set and a factor of 2 better than those reported in the recent Arzoumanian et al. paper.We also present PPTA directional sensitivity curves and find that for the most sensitive region on the sky, the current data set is sensitive to GWs from circular supermassive binary black holes with chirp masses of 109M⊙ out to a luminosity distance of about 100 Mpc. Finally, we set an upper limit of 4 × 10-3 Mpc-3 Gyr-1 at 95 per cent confidence on the coalescence rate of nearby (z ≲ 0.1) supermassive binary black holes in circular orbits with chirp masses of 1010M⊙.

Published
2014

71. Rheumatoid arthritis and incident fracture in women: a case-control study

Author

Brennan, SL, Toomey, L, Kotowicz, MA, Henry, MJ, Griffiths, H, Pasco, JA, Brennan, SL, Toomey, L, Kotowicz, MA, Henry, MJ, Griffiths, H, and Pasco, JA

Abstract

BACKGROUND: To examine fracture incidence in women with rheumatoid arthritis (RA) for an entire geographical region of south-eastern Australia. METHODS: Women aged 35 years and older, resident in the Barwon Statistical Division (BSD) and clinically diagnosed with RA 1994-2001 were eligible for inclusion as cases (n = 1,008). The control population (n = 172,422) comprised the entire female BSD population aged 35 years and older, excluding those individuals identified as cases. Incident fractures were extracted from the prospective Geelong Osteoporosis Study Fracture Grid. We calculated rate ratios (RR) and 95% confidence intervals (CI) to compare the age-adjusted rate of fracture between the RA and non-RA populations, and used a chi-square test to compare proportions of fractures between women with and without RA, and a two-sided Mann-Whitney U-test to examine age-differences. RESULTS: Among 1,008 women with RA, 19 (1.9%) sustained a fracture, compared to 1,981 fractures sustained by the 172,422 women without RA (1.2%). Fracture rates showed a trend for being greater among women diagnosed with RA (age-adjusted RR 1.43, 95%CI 0.98-2.09, p = 0.08). Women with RA sustained vertebral fractures at twice the expected frequency, whereas hip fractures were underrepresented in the RA population (p < 0.001). RA status was not associated with the likelihood of sustaining a fracture at sites adjacent to joints most commonly affected by RA (p = 0.22). CONCLUSION: Given that women with RA have a greater risk of fracture compared to women without RA, these patients may be a suitable target population for anti-resorptive agents; however, larger studies are warranted.

Published
2014

72. Limitations in timing precision due to single-pulse shape variability in millisecond pulsars

Author

Shannon, R., Oslowski, S., Dai, S., Bailes, M., Hobbs, G., Manchester, R., van Straten, W., Raithel, C., Ravi, V., Toomey, L., Bhat, Ramesh, Burke-Spolaor, S., Coles, W., Keith, M., Kerr, M., Levin, Y., Sarkissian, J., Wang, J., Wen, L., Zhu, X., Shannon, R., Oslowski, S., Dai, S., Bailes, M., Hobbs, G., Manchester, R., van Straten, W., Raithel, C., Ravi, V., Toomey, L., Bhat, Ramesh, Burke-Spolaor, S., Coles, W., Keith, M., Kerr, M., Levin, Y., Sarkissian, J., Wang, J., Wen, L., and Zhu, X.

Abstract

High-sensitivity radio-frequency observations of millisecond pulsars usually show stochastic, broad-band, pulse-shape variations intrinsic to the pulsar emission process. These variations induce jitter noise in pulsar timing observations; understanding the properties of this noise is of particular importance for the effort to detect gravitational waves with pulsar timing arrays. We assess the short-term profile and timing stability of 22 millisecond pulsars that are part of the Parkes Pulsar Timing Array sample by examining intraobservation arrival time variability and single-pulse phenomenology. In 7 of the 22 pulsars, in the band centred at approximately 1400 MHz, we find that the brightest observations are limited by intrinsic jitter. We find consistent results, either detections or upper limits, for jitter noise in other frequency bands. PSR J1909-3744 shows the lowest levels of jitter noise, which we estimate to contribute ~10 ns root mean square error to the arrival times for hour-duration observations. Larger levels of jitter noise are found in pulsars with wider pulses and distributions of pulse intensities. The jitter noise in PSR J0437-4715 decorrelates over a bandwidth of ~2 GHz. We show that the uncertainties associated with timing pulsar models can be improved by including physically motivated jitter uncertainties. Pulse-shape variations will limit the timing precision at future, more sensitive, telescopes; it is imperative to account for this noise when designing instrumentation and timing campaigns for these facilities.

Published
2014

73. An all-sky search for continuous gravitational waves in the Parkes Pulsar Timing Array data set

Author

Zhu, X., Hobbs, G., Wen, L., Coles, W., Wang, J., Shannon, R., Manchester, R., Bailes, M., Bhat, Ramesh, Burke-Spolaor, S., Dai, S., Keith, M., Kerr, M., Levin, Y., Madison, D., Oslowski, S., Ravi, V., Toomey, L., van Straten, W., Zhu, X., Hobbs, G., Wen, L., Coles, W., Wang, J., Shannon, R., Manchester, R., Bailes, M., Bhat, Ramesh, Burke-Spolaor, S., Dai, S., Keith, M., Kerr, M., Levin, Y., Madison, D., Oslowski, S., Ravi, V., Toomey, L., and van Straten, W.

Abstract

We present results of an all-sky search in the Parkes Pulsar Timing Array (PPTA) Data Release 1 data set for continuous gravitational waves (GWs) in the frequency range from 5 × 10−9 to 2 × 10−7 Hz. Such signals could be produced by individual supermassive binary black hole systems in the early stage of coalescence. We phase up the pulsar timing array data set to form, for each position on the sky, two data streams that correspond to the two GW polarizations and then carry out an optimal search for GW signals on these data streams. Since no statistically significant GWs were detected, we place upper limits on the intrinsic GW strain amplitude h0 for a range of GW frequencies. For example, at 10−8 Hz our analysis has excluded with 95 per cent confidence the presence of signals with h0 ≥ 1.7 × 10−14. Our new limits are about a factor of 4 more stringent than those of Yardley et al. based on an earlier PPTA data set and a factor of 2 better than those reported in the recent Arzoumanian et al. paper. We also present PPTA directional sensitivity curves and find that for the most sensitive region on the sky, the current data set is sensitive to GWs from circular supermassive binary black holes with chirp masses of 109 M☉ out to a luminosity distance of about 100 Mpc. Finally, we set an upper limit of 4 × 10−3 Mpc−3 Gyr−1 at 95 per cent confidence on the coalescence rate of nearby (z ≤ 0.1) supermassive binary black holes in circular orbits with chirp masses of 1010 M☉.

Published
2014

74. Searching for gravitational wave memory bursts with the Parkes Pulsar Timing Array

Author

Wang, J. B., primary, Hobbs, G., additional, Coles, W., additional, Shannon, R. M., additional, Zhu, X. J., additional, Madison, D. R., additional, Kerr, M., additional, Ravi, V., additional, Keith, M. J., additional, Manchester, R. N., additional, Levin, Y., additional, Bailes, M., additional, Bhat, N. D. R., additional, Burke-Spolaor, S., additional, Dai, S., additional, Osłowski, S., additional, van Straten, W., additional, Toomey, L., additional, Wang, N., additional, and Wen, L., additional

Published
2014
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75. Searching for gravitational wave memory bursts with the Parkes Pulsar Timing Array.

Author

J. B. Wang, Hobbs, G., Coles, W., Shannon, R. M., X. J. Zhu, Madison, D. R., Kerr, M., Ravi, V., Keith, M. J., Manchester, R. N., Levin, Y., Bailes, M., Bhat, N. D. R., Burke-Spolaor, S., Dai, S., Osłowski, S., van Straten, W., Toomey, L., N. Wang, and L. Wen

Subjects
BINARY pulsars, GRAVITATIONAL wave astronomy, DOMAIN walls (String models), GALAXIES, INTEGRAL field spectroscopy, FIBER optical sensors, ASTRONOMICAL observations, ASTRONOMICAL observatories
Abstract

Anisotropic bursts of gravitational radiation produced by events such as supermassive black hole mergers leave permanent imprints on space. Such gravitational wave 'memory'(GWM) signals are, in principle, detectable through pulsar timing as sudden changes in the apparent pulse frequency of a pulsar. If an array of pulsars is monitored as a GWM signal passes over the Earth, the pulsars would simultaneously appear to change pulse frequency by an amount that varies with their sky position in a quadrupolar fashion. Here, we describe a search algorithm for such events and apply the algorithm to approximately six years of data from the Parkes Pulsar Timing Array. We find no GWM events and set an upper bound on the rate for events which could have been detected. We show, using simple models of black hole coalescence rates, that this non-detection is not unexpected. [ABSTRACT FROM AUTHOR]

Published
2015
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76. Good Cooking vs. Drinking

Author

Toomey, L. A., Toomey, L. A., Toomey, L. A., and Toomey, L. A.

Abstract

Catholic world. / Volume 64, Issue 382, Page(s) 480-483, (dlps) volume: bac8387.0064.382, (dlps) article: bac8387.0064.382:8, http://quod.lib.umich.edu/t/text/accesspolicy.html

77. Abstraction of Methyl from Neutral Fischer-Type Carbene Complexes:  A New Site for Nucleophilic Attack

Author

Toomey, L. M. and Atwood, J. D.

Abstract

Reactions of Fischer-type carbene complexes, M(CO)5(C(OMe)Ph) (M = Cr, W), with metal carbonyl anions (M‘- = CpFe(CO)2-, Re(CO)5-, Mn(CO)4PPh3-, Co(CO)3PPh3-, Cp*Cr(CO)3-, CpMo(CO)3-) result in demethylation of the carbene complexes. The products are M(CO)5C(O)Ph- and M‘−Me, characterized by infrared and NMR spectroscopy. A slower rate for reaction with W(CO)5(C(OEt)Ph) in comparison to the methyl analogue is consistent with nucleophilic attack of the metal carbonyl anion on the methyl of the methoxy group of the carbene. This is a new type of nucleophilic attack on a Fischer-type carbene.

Published
1997

78. Diorganogallium β-Diketonates and Their Lewis Acid−Base Adducts. Crystal and Molecular Structures of Mes<INF>2</INF>Ga(hfac) and Me<INF>2</INF>Ga(hfac)·NC<INF>5</INF>H<INF>5</INF>

Author

Beachley, O. T., Jr., Gardinier, J. R., Churchill, M. R., and Toomey, L. M.

Abstract

Compounds of the type R2Ga(bdk) (R = Me, Et, Mes (mesityl); bdk = 2,4-pentanedionato (acac), 1,1,1-trifluoro-2,4-pentanedionato (tfac), 1,1,1,5,5,5-hexafluoro-2,4-penatedionato (hfac), 2,2,6,6-tetramethyl-3,5-heptanedionato (tmhd)) have been prepared by multiple routes, including hydrocarbon elimination, metathesis, and ligand redistribution reactions, and fully characterized by elemental analyses, cryoscopic molecular weight studies in benzene, and IR and multinuclear NMR spectroscopic studies. An X-ray structural study of Mes2Ga(hfac) demonstrated four-coordinate gallium with σ bonds to the two mesityl rings and to the two oxygen atoms of the β-diketonate ligand. The Lewis acidities of the diorganogallium β-diketonate derivatives toward NMe3 and/or pyridine were also investigated. Two adducts, Me2Ga(hfac)·NMe and Me2Ga(hfac)·py, were stable to dissociation at room temperature and thus were fully characterized by elemental analysis, cryoscopic molecular weight studies in benzene, vapor pressure−temperature studies, and IR and multinuclear NMR (including variable temperature) spectroscopic studies. The compound Me2Ga(hfac)·py was also characterized by an X-ray structural study. The structure involved five-coordinate gallium with one Ga−N, two (inequivalent) Ga−O, and two Ga−C bonds.

Published
1998

79. Room Temperature Cyclopentadiene Elimination Reaction for the Synthesis of Diethylgallium−Amides, −Phosphides, and −Thiolates. Crystal and Molecular Structures of [Et<INF>2</INF>GaP(t-Bu)<INF>2</INF>]<INF>2</INF> and [Et<INF>2</INF>GaS(SiPh<INF>3</INF>)]<INF>2</INF>

Author

Beachley, O. T., Jr., Rosenblum, D. B., Churchill, M. R., Lake, C. H., and Toomey, L. M.

Abstract

The compounds [Et2GaNEt2]2, [Et2GaN(H)(Me)]2, [Et2GaN(H)(t-Bu)]2, [Et2GaP(i-Pr)2]2, [Et2GaP(t-Bu)2]2, and [Et2GaS(SiPh3)]2 have been prepared in high yields at room temperature by the elimination of cyclopentadiene from Et2Ga(C5H5) and the corresponding amine, phosphine, or thiol. The three diethylgallium amides and [Et2GaP(i-Pr)2]2 are liquids, whereas the other phosphide and the thiolate are crystalline solids at room temperature. All compounds were fully characterized by elemental analyses, 1H and 31P NMR spectroscopy, and cryoscopic molecular weight studies in benzene, as appropriate, and are dimeric in solution. The crystalline compounds [Et2GaP(t-Bu)2]2, and [Et2GaS(SiPh3)]2 were characterized by X-ray structural studies. Even though [Et2GaN(H)(t-Bu)]2 and [Et2GaS(SiPh3)]2 were prepared at room temperature and isolated in high yield, 1H NMR studies revealed that neither compound was formed in high yield in solution. Removal of the cyclopentadiene by either dimerization or distillation and/or dimerization of the gallium product are necessary to prevent the back-reaction to re-form the reactants.

Published
1996

81. IBM Parallel FORTRAN

Author

Toomey, L. J., primary, Plachy, E. C., additional, Scarborough, R. G., additional, Sahulka, R. J., additional, Shaw, J. F., additional, and Shannon, A. W., additional

Published
1988
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85. Studying the Solar system with the International Pulsar Timing Array

Author

R. S. Lynch, L. Toomey, Paul Demorest, J. K. Swiggum, X. Siemens, Gregory Desvignes, A. Possenti, T. J. W. Lazio, Gilles Theureau, D. R. Madison, Lucas Guillemot, Joseph Simon, Renée Spiewak, Kejia Lee, Alberto Sesana, Andrea N. Lommen, Gemma H. Janssen, Ramesh Karuppusamy, Xing-Jiang Zhu, Ismaël Cognard, Chiara M. F. Mingarelli, Benjamin Stappers, Stefan Oslowski, Sean T. McWilliams, Scott M. Ransom, S. A. Sanidas, David J. Nice, Kang Liu, G. Shaifullah, Marjorie Gonzalez, Y J Guo, Caterina Tiburzi, Robert D. Ferdman, James M. Cordes, P. Lazarus, N. D. R. Bhat, Jonathan R. Gair, Daniel R. Stinebring, George Hobbs, Sarah Burke-Spolaor, Nipuni Palliyaguru, Benetge Perera, Daniel J. Reardon, Richard N. Manchester, Shi Dai, Michael Kramer, Ryan Shannon, A. Brazier, R. van Haasteren, Joris P. W. Verbiest, Zaven Arzoumanian, M. Burgay, Timothy T. Pennucci, W. van Straten, Lina Levin, K. Plant, Ingrid H. Stairs, Peter A. Gentile, Duncan R. Lorimer, E. Graikou, Weiwei Zhu, N. Garver-Daniels, D. J. Champion, Matthew Bailes, S. J. Chamberlin, Delphine Perrodin, Sourav Chatterjee, Kevin Stovall, Michael Keith, Matthew Kerr, Timothy Dolch, J. B. Wang, R. N. Caballero, C. G. Bassa, Emmanuel Fonseca, Michael T. Lam, Stephen Taylor, Paul D. Lasky, J. W. McKee, Maura McLaughlin, Laboratoire de physique et chimie de l'environnement (LPCE), Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Laboratoire Univers et Théories (LUTH (UMR_8102)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS), Caballero, R, Guo, Y, Lee, K, Lazarus, P, Champion, D, Desvignes, G, Kramer, M, Plant, K, Arzoumanian, Z, Bailes, M, Bassa, C, Bhat, N, Brazier, A, Burgay, M, Burke-Spolaor, S, Chamberlin, S, Chatterjee, S, Cognard, I, Cordes, J, Dai, S, Demorest, P, Dolch, T, Ferdman, R, Fonseca, E, Gair, J, Garver-Daniels, N, Gentile, P, Gonzalez, M, Graikou, E, Guillemot, L, Hobbs, G, Janssen, G, Karuppusamy, R, Keith, M, Kerr, M, Lam, M, Lasky, P, Lazio, T, Levin, L, Liu, K, Lommen, A, Lorimer, D, Lynch, R, Madison, D, Manchester, R, Mckee, J, Mclaughlin, M, Mcwilliams, S, Mingarelli, C, Nice, D, Osłowski, S, Palliyaguru, N, Pennucci, T, Perera, B, Perrodin, D, Possenti, A, Ransom, S, Reardon, D, Sanidas, S, Sesana, A, Shaifullah, G, Shannon, R, Siemens, X, Simon, J, Spiewak, R, Stairs, I, Stappers, B, Stinebring, D, Stovall, K, Swiggum, J, Taylor, S, Theureau, G, Tiburzi, C, Toomey, L, van Haasteren, R, van Straten, W, Verbiest, J, Wang, J, Zhu, X, and Zhu, W

Subjects
Solar System, Dwarf planet, FOS: Physical sciences, Astrophysics, Ephemeris, 01 natural sciences, Jovian, Pulsar, pulsars: general, 0103 physical sciences, Sensitivity (control systems), ephemerides, 010303 astronomy & astrophysics, Physics, Earth and Planetary Astrophysics (astro-ph.EP), methods: statistical, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Astronomy and Astrophysics, Planetary system, Ephemeride, methods: data analysis, 13. Climate action, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Physics::Space Physics, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Methods: data analysi, Reference frame, Astrophysics - Earth and Planetary Astrophysics
Abstract

Pulsar-timing analyses are sensitive to errors in the solar-system ephemerides (SSEs) that timing models utilise to estimate the location of the solar-system barycentre, the quasi-inertial reference frame to which all recorded pulse times-of-arrival are referred. Any error in the SSE will affect all pulsars, therefore pulsar timing arrays (PTAs) are a suitable tool to search for such errors and impose independent constraints on relevant physical parameters. We employ the first data release of the International Pulsar Timing Array to constrain the masses of the planet-moons systems and to search for possible unmodelled objects (UMOs) in the solar system. We employ ten SSEs from two independent research groups, derive and compare mass constraints of planetary systems, and derive the first PTA mass constraints on asteroid-belt objects. Constraints on planetary-system masses have been improved by factors of up to 20 from the previous relevant study using the same assumptions, with the mass of the Jovian system measured at 9.5479189(3)$\times10^{-4}$ $M_{\odot}$. The mass of the dwarf planet Ceres is measured at 4.7(4)$\times10^{-10}$ $M_{\odot}$. We also present the first sensitivity curves using real data that place generic limits on the masses of UMOs, which can also be used as upper limits on the mass of putative exotic objects. For example, upper limits on dark-matter clumps are comparable to published limits using independent methods. While the constraints on planetary masses derived with all employed SSEs are consistent, we note and discuss differences in the associated timing residuals and UMO sensitivity curves., Comment: Accepted for publication by the Monthly Notices of the Royal Astronomical Society

Published
2018
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86. Effects of zooplankton abundance on the spawning phenology of winter-spawning Downs herring (Clupea harengus).

Author

Marchal P, Giraldo C, Johns D, Lefebvre S, Loots C, and Toomey L

Subjects
Animals, North Sea, Seasons, Fishes physiology, Zooplankton physiology, Reproduction physiology, Temperature
Abstract

We have investigated phenological shifts in autumn- and winter-spawning Atlantic herring (Clupea harengus) in the Eastern English Channel and the Southern North Sea (Downs component), in relation to temperature and the availability of potential zooplanktonic prey (Calanus finmarchicus, Calanus helgolandicus, Temora longicornis). A two-tiered approach building on the monthly distribution of commercial herring landings was developed, which consisted of, (1) calculating the timing and duration of spawning season based on estimated deviations from basic harmonic signals and, (2) analysing their inter-annual variations in relation to biotic (zooplankton abundance) and abiotic (temperature) environmental variables through time series analyses. The start, midpoint and ending of herring spawning season were increasingly delayed over the period 1999-2021, a process which was correlated with the abundance of Calanus finmarchicus. The resulting duration of spawning season slightly decreased. Direct effects of sea temperatures on any phenological metrics could not be clearly evidenced. Different ecological processes were likely involved in the start and ending of spawning season. Additional covariates (including size/age composition, the biotic and abiotic factors other than those examined in our study) could contribute to a better explanation of the phenological drift in Downs herring spawning., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2025 Marchal et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Published
2025
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88. Comparative analysis of blood protein fractions in two mediterranean farmed fish: Dicentrarchus labrax and Sparus aurata.

Author

Alfonso S, Fiocchi E, Toomey L, Boscarato M, Manfrin A, Dimitroglou A, Papaharisis L, Passabi E, Stefani A, Lembo G, and Carbonara P

Subjects
Animals, Aquaculture, Mediterranean Sea, Bass blood, Sea Bream blood, Blood Proteins analysis
Abstract

Total protein levels in fish are widely used in health and welfare studies, providing a simple and accessible measure. However, the multifaceted role of blood proteins makes it sometimes challenging to link total protein content to specific health issues, while specific protein fractions may offer more precise insights into fish biology and health, particularly in farmed fish species where such data is often lacking. Data were gathered from two experiments involving Dicentrarchus labrax and Sparus aurata, key species in European marine aquaculture. The aim was (1) to assess how different globulin fractions contribute to total protein content in blood and (2) how these contributions vary across different sampling times in healthy animals. In D. labrax, the beta1 globulin fraction emerged as the major contributor (34.16%), followed by albumin and alpha2 globulins (18.24% and 16.41%, respectively). In contrast, pre-albumins and alpha1 fractions had the least contribution (5.49% and 7.71%). S. aurata exhibited albumin as the primary contributor (23.39%), followed by beta1 and alpha2 globulins (19.71% and 19.15%, respectively), with gamma and alpha1 fractions contributing the least (5.34% and 8.63%). Notably, the study revealed relatively stable contributions of globulin fractions to total proteins within both species, albeit with minor variations over time, potentially linked to environmental and individual factors. Furthermore, larger fish displayed higher total protein levels. This research underscores the need for further investigation into the diverse factors influencing globulin contributions to total proteins, ultimately enhancing health and welfare monitoring for farmed fish species., (© 2024. The Author(s).)

Published
2024
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89. Growth performance, gut microbiota composition, health and welfare of European sea bass (Dicentrarchus labrax) fed an environmentally and economically sustainable low marine protein diet in sea cages.

Author

Alfonso S, Mente E, Fiocchi E, Manfrin A, Dimitroglou A, Papaharisis L, Barkas D, Toomey L, Boscarato M, Losasso C, Peruzzo A, Stefani A, Zupa W, Spedicato MT, Nengas I, Lembo G, and Carbonara P

Subjects
Animals, Diet, Fish Oils metabolism, Fatty Acids metabolism, Diet, Protein-Restricted, Animal Feed analysis, Bass metabolism, Gastrointestinal Microbiome
Abstract

The large use of fish meal/fish oil in carnivorous fish feeds is the main concern regarding environmental sustainability of aquaculture. Here, we evaluated the effects of an innovative diet, designed to be (1) environmentally sustainable by lowering the marine protein content while being (2) cost effective by using sustainable alternative raw materials with acceptable cost and produced on an industrial scale, on growth performance, gut microbiota composition, health and welfare of European sea bass (Dicentrarchus labrax), a key species of the Mediterranean marine aquaculture, reared in sea cages. Results show that the specific growth rate of fish fed the low marine protein diet was significantly lower than those fed conventional diet (0.67% vs 0.69%). Fatty acid profile of fillets from fish fed a low marine protein diet presented significant lower n-6 and higher n-3 content when compared to conventional ones. Then, a significant increase in the abundance of Vibrio and reduction of Photobacterium were found in the gut of fish fed with the low marine protein diet but effects on sea bass health needs further investigation. Finally, no major health and welfare alterations for fish fed the low marine protein diet were observed, combined with a potential slight benefit related to humoral immunity. Overall, these results suggest that despite the low marine protein diet moderately affects growth performance, it nevertheless may enhance environmental and economic sustainability of the sea bass aquaculture., (© 2023. The Author(s).)

Published
2023
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90. Impact of temperature on Downs herring (Clupea harengus) embryonic stages: First insights from an experimental approach.

Author

Toomey L, Giraldo C, Loots C, Mahé K, Marchal P, and MacKenzie K

Subjects
Animals, Female, Humans, Temperature, Larva, Hot Temperature, Ecosystem, Fishes
Abstract

Among all human-induced pressures, ocean warming is expected to be one of the major drivers of change in marine ecosystems. Fish species are particularly vulnerable during embryogenesis. Here, the impact of temperature was assessed on embryonic stages of Atlantic herring (Clupea harengus), a species of high socio-economic interest, with a particular focus on the under-studied eastern English Channel winter-spawning component (Downs herring). Key traits linked to growth and development were experimentally evaluated at three temperatures (8°C, 10°C and 14°C), from fertilization to hatching, in standardized controlled conditions. Overall negative impacts of increased temperature were observed on fertilization rate, mean egg diameter at eyed stage, hatching rate and yolk sac volume. A faster developmental rate and a change in development stage frequency of newly hatched larvae were also observed at higher temperature. Potential parental effects were detected for four key traits (i.e. fertilization rate, eyed survival rate, mean egg diameter and hatching rate), despite a limited number of families. For instance, a large variability among families was shown in survival rate at eyed stage (between 0 and 63%). Potential relationships between maternal characteristics and embryo traits were therefore explored. We show that a substantial proportion of variance (between 31 and 70%) could be explained by the female attributes considered. More particularly, age, traits linked to life history (i.e. asymptotic average length and Brody growth rate coefficient), condition and length were important predictors of embryonic key traits. Overall, this study constitutes a stepping-stone to investigate potential consequences of warming on Downs herring recruitment and provides first insights on potential parental effects., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Toomey et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Published
2023
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91. AquaDesign: A tool to assist aquaculture production design based on abiotic requirements of animal species.

Author

Butruille G, Thomas M, Pasquet A, Amoussou N, Toomey L, Rosenstein A, Chauchard S, and Lecocq T

Subjects
Animals, Fresh Water, Agriculture, Aquaculture methods
Abstract

Farming new species and promoting polyculture can enhance aquaculture sustainability. This implies to define the rearing conditions that meet the ecological requirements of a target species and/or to assess if different species can live in the same farming environment. However, there is a large number of rearing conditions and/or taxon combinations that can be considered. In order to minimise cumbersome and expensive empirical trials to explore all possibilities, we introduce a tool, AquaDesign. It is based on a R-script and package which help to determine farming conditions that are most likely suitable for species through in silico assessment. We estimate farming conditions potentially suitable for an aquatic organism by considering the species niche. We define the species n-dimensional niche hypervolume using a correlative approach in which the species niche is estimated by relating distribution data to environmental conditions. Required input datasets are mined from several public databases. The assistant tool allows users to highlight (i) abiotic conditions that are most likely suitable for species and (ii) combinations of species potentially able to live in the same abiotic environment. Moreover, it offers the possibility to assess if a particular set of abiotic conditions or a given farming location is potentially suitable for the monoculture or the polyculture of species of interest. Our tool provides useful pieces of information to develop freshwater aquacultures. Using the large amount of biogeographic and abiotic information available in public databases allows us to propose a pragmatic and operational tool even for species for which abiotic requirements are poorly or not available in literature such as currently non-produced species. Overall, we argue that the assistant tool can act as a stepping stone to promote new aquatic productions which are required to enhance aquaculture sustainability., Competing Interests: The authors have declared that no competing interests exist.

Published
2022
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92. Split it up and see: using proxies to highlight divergent inter-populational performances in aquaculture standardised conditions.

Author

Toomey L, Dellicour S, Kapusta A, Żarski D, Buhrke F, Milla S, Fontaine P, and Lecocq T

Subjects
Animals, Domestication, Phenotype, Aquaculture, Perches
Abstract

Background: Considering wild inter-populational phenotypic differentiation can facilitate domestication and subsequent production of new species. However, comparing all populations across a species range to identify those exhibiting suitable key traits for aquaculture (KTA; i.e. important for domestication and subsequent production) expressions is not feasible. Therefore, proxies highlighting inter-populational divergences in KTA are needed. The use of such proxies would allow to identify, prior to bioassays, the wild population pairs which are likely to present differentiations in KTA expressions in aquaculture conditions. Here, we assessed the relevance of three alternative proxies: (i) genetic distance, (ii) habitat divergence, and (iii) geographic/hydrologic distances. We performed this evaluation on seven allopatric populations of Perca fluviatilis for which divergences in KTA had already been shown., Results: We showed differences in the correlation degree between the alternative proxy-based and KTA-based distance matrices, with the genetic proxy being correlated to the highest number of KTA. However, no proxy was correlated to all inter-populational divergences in KTA., Conclusion: For future domestication trials, we suggest using a multi-proxy assessment along with a prioritisation strategy to identify population pairs which are of interest for further evaluation in bioassays., (© 2021. The Author(s).)

Published
2021
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94. Comparison of single- and multi-trait approaches to identify best wild candidates for aquaculture shows that the simple way fails.

Author

Toomey L, Lecocq T, Bokor Z, Espinat L, Ferincz Á, Goulon C, Vesala S, Baratçabal M, Barry MD, Gouret M, Gouron C, Staszny Á, Mauduit E, Mean V, Muller I, Schlick N, Speder K, Thumerel R, Piatti C, Pasquet A, and Fontaine P

Subjects
Animals, Breeding, Humans, Perches growth & development, Phenotype, Polymorphism, Single Nucleotide genetics, Aquaculture, Domestication, Perches genetics, Quantitative Trait Loci genetics
Abstract

In agriculture, diversifying production implies picking up, in the wild biodiversity, species or populations that can be domesticated and fruitfully produced. Two alternative approaches are available to highlight wild candidate(s) with high suitability for aquaculture: the single-trait (i.e. considering a single phenotypic trait and, thus, a single biological function) and multi-trait (i.e. considering multiple phenotypic traits involved in several biological functions) approaches. Although the former is the traditional and the simplest method, the latter could be theoretically more efficient. However, an explicit comparison of advantages and pitfalls between these approaches is lacking to date in aquaculture. Here, we compared the two approaches to identify best candidate(s) between four wild allopatric populations of Perca fluviatilis in standardised aquaculture conditions. Our results showed that the single-trait approach can (1) miss key divergences between populations and (2) highlight different best candidate(s) depending on the trait considered. In contrast, the multi-trait approach allowed identifying the population with the highest domestication potential thanks to several congruent lines of evidence. Nevertheless, such an integrative assessment is achieved with a far more time-consuming and expensive study. Therefore, improvements and rationalisations will be needed to make the multi-trait approach a promising way in the aquaculture development.

Published
2020
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95. Domestication may affect the maternal mRNA profile in unfertilized eggs, potentially impacting the embryonic development of Eurasian perch (Perca fluviatilis).

Author

Rocha de Almeida T, Alix M, Le Cam A, Klopp C, Montfort J, Toomey L, Ledoré Y, Bobe J, Chardard D, Schaerlinger B, and Fontaine P

Subjects
Animals, Embryonic Development genetics, Domestication, Ovum metabolism, Perches embryology, Perches genetics, RNA, Messenger, Stored genetics, Transcriptome genetics
Abstract

Domestication is an evolutionary process during which we expect populations to progressively adapt to an environment controlled by humans. It is accompanied by genetic and presumably epigenetic changes potentially leading to modifications in the transcriptomic profile in various tissues. Reproduction is a key function often affected by this process in numerous species, regardless of the mechanism. The maternal mRNA in fish eggs is crucial for the proper embryogenesis. Our working hypothesis is that modifications of maternal mRNAs may reflect potential genetic and/or epigenetic modifications occurring during domestication and could have consequences during embryogenesis. Consequently, we investigated the trancriptomic profile of unfertilized eggs from two populations of Eurasian perch. These two populations differed by their domestication histories (F1 vs. F7+-at least seven generations of reproduction in captivity) and were genetically differentiated (FST = 0.1055, p<0.05). A broad follow up of the oogenesis progression failed to show significant differences during oogenesis between populations. However, the F1 population spawned earlier with embryos presenting an overall higher survivorship than those from the F7+ population. The transcriptomic profile of unfertilized eggs showed 358 differentially expressed genes between populations. In conclusion, our data suggests that the domestication process may influence the regulation of the maternal transcripts in fish eggs, which could in turn explain differences of developmental success., Competing Interests: The authors declare that they have no competing interests.

Published
2019
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96. Responses of the arcto-boreal krill species Thysanoessa inermis to variations in water temperature: coupling Hsp70 isoform expressions with metabolism.

Author

Huenerlage K, Cascella K, Corre E, Toomey L, Lee CY, Buchholz F, and Toullec JY

Subjects
Amino Acid Sequence, Animals, Euphausiacea growth & development, HSP70 Heat-Shock Proteins classification, HSP70 Heat-Shock Proteins genetics, High-Throughput Nucleotide Sequencing, Kinetics, Phylogeny, Protein Isoforms classification, Protein Isoforms genetics, Protein Isoforms metabolism, RNA chemistry, RNA isolation & purification, RNA metabolism, Sequence Alignment, Sequence Analysis, RNA, Temperature, Transcriptome, Water chemistry, Euphausiacea metabolism, HSP70 Heat-Shock Proteins metabolism
Abstract

Recent studies have indicated a metabolic temperature sensitivity in both the arcto-boreal krill species Thysanoessa inermis and Thysanoessa raschii that may determine these species' abundance and population persistence at lower latitudes (up to 40° N). T. inermis currently dominates the krill community in the Barents Sea and in the high Arctic Kongsfjord. We aimed to increase the knowledge on the upper thermal limit found in the latter species by estimating the CT 50 value (19.7 °C) (critical temperature at which 50 % of animals are reactive) and by linking metabolic rate measurements with molecular approaches. Optical oxygen sensors were used to measure respiration rates in steps of 2 °C (from 0 to 16 °C). To follow the temperature-mediated mechanisms of passive response, i.e., as a proxy for molecular stress, molecular chaperone heat shock protein 70 (Hsp70) sequences were extracted from a transcriptome assembly, and the gene expression kinetics were monitored during an acute temperature exposure to 6 or 10 °C with subsequent recovery at 4 °C. Our results showed upregulation of hsp70 genes, especially the structurally constitutive and mitochondrial isoforms. These findings confirmed the temperature sensitivity of T. inermis and showed that the thermal stress took place before reaching the upper temperature limit estimated by respirometry at 12 °C. This study provides a baseline for further investigations into the thermal tolerances of arcto-boreal Thysanoessa spp. and comparisons with other krill species under different climatic regimes, especially Antarctica.

Published
2016
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97. Rheumatoid arthritis and incident fracture in women: a case-control study.

Author

Brennan SL, Toomey L, Kotowicz MA, Henry MJ, Griffiths H, and Pasco JA

Subjects
Adult, Aged, Arthritis, Rheumatoid diagnosis, Case-Control Studies, Chi-Square Distribution, Female, Fractures, Bone diagnosis, Hip Fractures epidemiology, Humans, Incidence, Middle Aged, Risk Factors, Sex Factors, Spinal Fractures epidemiology, Time Factors, Victoria epidemiology, Arthritis, Rheumatoid epidemiology, Fractures, Bone epidemiology
Abstract

Background: To examine fracture incidence in women with rheumatoid arthritis (RA) for an entire geographical region of south-eastern Australia., Methods: Women aged 35 years and older, resident in the Barwon Statistical Division (BSD) and clinically diagnosed with RA 1994-2001 were eligible for inclusion as cases (n = 1,008). The control population (n = 172,422) comprised the entire female BSD population aged 35 years and older, excluding those individuals identified as cases. Incident fractures were extracted from the prospective Geelong Osteoporosis Study Fracture Grid. We calculated rate ratios (RR) and 95% confidence intervals (CI) to compare the age-adjusted rate of fracture between the RA and non-RA populations, and used a chi-square test to compare proportions of fractures between women with and without RA, and a two-sided Mann-Whitney U-test to examine age-differences., Results: Among 1,008 women with RA, 19 (1.9%) sustained a fracture, compared to 1,981 fractures sustained by the 172,422 women without RA (1.2%). Fracture rates showed a trend for being greater among women diagnosed with RA (age-adjusted RR 1.43, 95%CI 0.98-2.09, p = 0.08). Women with RA sustained vertebral fractures at twice the expected frequency, whereas hip fractures were underrepresented in the RA population (p < 0.001). RA status was not associated with the likelihood of sustaining a fracture at sites adjacent to joints most commonly affected by RA (p = 0.22)., Conclusion: Given that women with RA have a greater risk of fracture compared to women without RA, these patients may be a suitable target population for anti-resorptive agents; however, larger studies are warranted.

Published
2014
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98. Nursing leadership in disaster preparedness and response.

Author

Knebel AR, Toomey L, and Libby M

Abstract

Nurses serve as leaders in disaster preparedness and response at multiple levels: within their own homes and neighborhoods, at disaster scenes, and the workplace, which can vary from a health care facility, in the community, or at the state, national, or international level. This chapter provides an overview on theories of leadership with a historical context for nursing leadership; setting the context for nursing leadership in disaster preparedness and response. Although few research studies exist, there are numerous examples of nurses who provide leadership for disaster preparedness and response. To define the current state of the science, the research studies cited in this chapter are supplemented with case studies from particular disasters. The major finding of this review is that nursing leadership in disaster preparedness and response is a field of study that needs to be developed.

Published
2012
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99. Midwife-led debriefing after operative birth: four to six year follow-up of a randomised trial [ISRCTN24648614].

Author

Small R, Lumley J, and Toomey L

Subjects
Adult, Depression, Postpartum psychology, Female, Follow-Up Studies, Humans, Maternal Welfare psychology, Mental Health, Pregnancy, Randomized Controlled Trials as Topic, Cesarean Section psychology, Counseling, Midwifery, Parturition psychology, Postnatal Care, Postoperative Care
Abstract

Background: There is little evidence that single-session debriefing is effective in reducing adverse mental health outcomes after trauma. Few trials have included long-term follow-up, but two also suggest possible negative effects of debriefing. We aimed to assess longer-term maternal health outcomes in a trial of midwife-led debriefing following an operative birth, given that findings at six months could not rule out a possible adverse effect of debriefing., Methods: Four to six years after participating in a midwife-led trial of debriefing following an operative birth, 1039/1041 women were mailed a questionnaire containing the Edinburgh Postnatal Depression Scale (EPDS) and the SF-36 health status measure., Results: Responses were obtained from 534 women (51.4%). Responders from the two trial groups remained comparable 4-6 years postpartum. No significant differences on maternal health outcomes were found between the trial groups., Conclusion: In the longer term, maternal health status was neither positively nor adversely affected by the experience of debriefing, despite a hint of adverse effects at six months postpartum. Short debriefing interventions have not proven effective in improving mental health outcomes for women following childbirth.

Published
2006
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100. Inhibition of HHV-8/KSHV infected primary effusion lymphomas in NOD/SCID mice by azidothymidine and interferon-alpha.

Author

Wu W, Rochford R, Toomey L, Harrington W Jr, and Feuer G

Subjects
Animals, Antineoplastic Agents therapeutic use, Apoptosis Regulatory Proteins, Epstein-Barr Virus Infections complications, Epstein-Barr Virus Infections prevention & control, Epstein-Barr Virus Infections virology, Herpesvirus 4, Human isolation & purification, Herpesvirus 8, Human isolation & purification, Humans, Membrane Glycoproteins metabolism, Mice, Mice, Inbred NOD, Mice, SCID, Reverse Transcriptase Inhibitors therapeutic use, Survival Rate, TNF-Related Apoptosis-Inducing Ligand, Time Factors, Tumor Cells, Cultured transplantation, Tumor Necrosis Factor-alpha metabolism, Apoptosis drug effects, Interferon-alpha therapeutic use, Lymphoma, B-Cell prevention & control, Lymphoma, B-Cell virology, Zidovudine therapeutic use
Abstract

Kaposi's sarcoma-associated herpesvirus/human herpesvirus type-8 (KSHV/HHV-8) is associated with primary effusion lymphomas (PEL), a rare form of B-cell lymphoma. PEL cell lines infected with HHV-8, but negative for Epstein-Barr virus (EBV), were analyzed for their tumorigenic potential in a small animal model system. Inoculation of PEL cell lines into non-obese diabetic/severe combined immunodeficient (NOD/SCID) mice results in efficient engraftment and tumorigenesis in vivo. PEL-engrafted NOD/SCID (PEL/SCID) mice displayed malignant ascites development with notable abdominal distension, consistent with the clinical manifestations of PEL in humans. Azidothymidine (AZT, zidovudine) and interferon-alpha (IFN-alpha) induce apoptosis in HHV-8+/EBV- PEL cells in culture, by induction of a tumor necrosis factor-related apoptosis inducing ligand (TRAIL) mediated suicide program and has been proposed as a therapy for herpesvirus-associated lymphomas. Daily injection of AZT and IFN-alpha significantly increased mean survival time (MST) of PEL/SCID mice suggesting that induction of apoptosis in PEL cells in vivo may be exploited as an effective relatively non-toxic therapy targeting HHV-8 infected PEL. These data demonstrate that the PEL/SCID mouse is an important preclinical model to characterize efficacy and anti-tumor mechanisms of new therapeutic targets in vivo and will be useful in the design and testing of agents in viral lymphoproliferative diseases.

Published
2005
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