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151. LUNASKA simultaneous neutrino searches with multiple telescopes

Author

Bray, J., Ekers, Ronald, James, C., Roberts, P., Brown, A., Phillips, C., Protheroe, R., Reynolds, J., McFadden, R., Aartsen, M., Bray, J., Ekers, Ronald, James, C., Roberts, P., Brown, A., Phillips, C., Protheroe, R., Reynolds, J., McFadden, R., and Aartsen, M.

Abstract

The most sensitive method for detecting neutrinos at the very highest energies is the lunar Cherenkov technique, which employs the Moon as a target volume, using conventional radio telescopes to monitor it for nanosecond-scale pulses of Cherenkov radiation from particle cascades in its regolith. Multiple-antenna radio telescopes are difficult to effectively combine into a single detector for this purpose, while single antennas are more susceptible to false events from radio interference, which must be reliably excluded for a credible detection to be made. We describe our progress in excluding such interference in our observations with the single-antenna Parkes radio telescope, and our most recent experiment (taking place the week before the ICRC) using it in conjunction with the Australia Telescope Compact Array, exploiting the advantages of both types of telescope.

Published
2011

152. Ionospheric propagation effects for UHE neutrino detection with the lunar Cherenkov technique

Author

McFadden, R., Ekers, Ronald, Bray, J., McFadden, R., Ekers, Ronald, and Bray, J.

Abstract

Lunar Cherenkov experiments aim to detect nanosecond pulses of Cherenkov emission produced during UHE cosmic ray or neutrino interactions in the lunar regolith. Pulses from these interactions are dispersed, and therefore reduced in amplitude, during propagation through the Earth's ionosphere. Pulse dispersion must therefore be corrected to maximise the received signal to noise ratio and subsequent chances of detection. The pulse dispersion characteristic may also provide a powerful signature to determine the lunar origin of a pulse and discriminate against pulses of terrestrial radio frequency interference (RFI). This characteristic is parameterised by the instantaneous Total Electron Content (TEC) of the ionosphere and therefore an accurate knowledge of the ionospheric TEC provides an experimental advantage for the detection and identification of lunar Cherenkov pulses. We present a new method to calibrate the dispersive effect of the ionosphere on lunar Cherenkov pulses using lunar Faraday rotation measurements combined with geomagnetic field models.

Published
2011

155. Lunar radio Cherenkov observations of UHE neutrinos

Author

Ekers, Ronald, James, C., Protheroe, R., McFadden, R., Ekers, Ronald, James, C., Protheroe, R., and McFadden, R.

Abstract

The lunar radio Cherenkov technique uses the moon as a large-volume detector for ultra-high energy (UHE) cosmic rays and neutrinos. We review the issues and techniques needed for sensitive radio detection of nanosecond pulses from UHE neutrino events in the lunar regolith. Historical experiments and limits are discussed. We compare experiments using single telescopes with focal plane array and both incoherent and coherent detection with aperture plane arrays of telescopes. Opportunities for future experiments at both high and low frequencies with massive arrays such as the SKA will be considered. © 2009.

Published
2009

156. Status report and future prospects on LUNASKA lunar observations with ATCA

Author

James, C., Ekers, Ronald, Alvarez-Muñiz, J., Protheroe, R., McFadden, R., Phillips, C., Roberts, P., James, C., Ekers, Ronald, Alvarez-Muñiz, J., Protheroe, R., McFadden, R., Phillips, C., and Roberts, P.

Abstract

LUNASKA (Lunar UHE Neutrino Astrophysics with the Square Kilometre Array) is a theoretical and experimental project developing the lunar Cherenkov technique for the next generation of giant radio-telescope arrays. Here we report on a series of observations with ATCA (the Australia Telescope Compact Array). Our current observations use three of the six 22 m ATCA antennas with a 600 MHz bandwidth at 1.2-1.8 GHz, analogue dedispersion filters to correct for the typical night-time ionospheric dispersion, and state-of-the-art 2 GHz FPGA-based digital pulse detection hardware. We have observed so as to maximise the UHE neutrino sensitivity in the region surrounding the galactic centre and to Centaurus A, to which current limits on the highest-energy neutrinos are relatively weak. Crown Copyright © 2009.

Published
2009

157. Developments in Nanosecond Pulse Detection Methods and Technology

Author

McFadden, R. A., Bhat, N. D. R., Ekers, R. D., James, C. W., Jones, D., Tingay, S. J., Roberts, P. P., Phillips, C. J., Protheroe, R. J., McFadden, R. A., Bhat, N. D. R., Ekers, R. D., James, C. W., Jones, D., Tingay, S. J., Roberts, P. P., Phillips, C. J., and Protheroe, R. J.

Abstract

A promising method for the detection of UHE neutrinos is the Lunar Cherenkov technique, which utilises Earth-based radio telescopes to detect the coherent Cherenkov radiation emitted when a UHE neutrino interacts in the outer layers of the Moon. The LUNASKA project aims to overcome the technological limitations of past experiments to utilise the next generation of radio telescopes in the search for these elusive particles. To take advantage of broad-bandwidth data from potentially thousands of antennas requires advances in signal processing technology. Here we describe recent developments in this field and their application in the search for UHE neutrinos, from a preliminary experiment using the first stage of an upgrade to the Australia Telescope Compact Array, to possibilities for fully utilising the completed Square Kilometre Array. We also explore a new real time technique for characterising ionospheric pulse dispersion which specifically measures ionospheric electron content that is line of sight to the moon., Comment: 4 pages, 1 figure, Proceedings from 30th ICRC, Merida, Mexico, 2007

Published
2008

158. Status Report and Future Prospects on LUNASKA Lunar Observations with ATCA

Author

James, C. W., Ekers, R. D., Alvarez-Muniz, J., Protheroe, R. J., McFadden, R. A., Phillips, C. J., Roberts, P., James, C. W., Ekers, R. D., Alvarez-Muniz, J., Protheroe, R. J., McFadden, R. A., Phillips, C. J., and Roberts, P.

Abstract

LUNASKA (Lunar UHE Neutrino Astrophysics with the Square Kilometre Array) is a theoretical and experimental project developing the lunar Cherenkov technique for the next generation of giant radio-telescope arrays. Here we report on a series of observations with ATCA (the Australia Telescope Compact Array). Our current observations use three of the six 22m ATCA antennas with a 600 MHz bandwidth at 1.2-1.8 GHz, analogue dedispersion filters to correct for the typical night-time ionospheric dispersion, and state-of-the-art 2 GHz FPGA-based digital pulse detection hardware. We have observed so as to maximise the UHE neutrino sensitivity in the region surrounding the galactic centre and to Centaurus A, to which current limits on the highest-energy neutrinos are relatively weak., Comment: 4 pages, 4 figures, presented at ARENA 2008, Rome, Italy

Published
2008
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160. LOFAR: The LOw-Frequency ARray

Author

van Haarlem, M. P., primary, Wise, M. W., additional, Gunst, A. W., additional, Heald, G., additional, McKean, J. P., additional, Hessels, J. W. T., additional, de Bruyn, A. G., additional, Nijboer, R., additional, Swinbank, J., additional, Fallows, R., additional, Brentjens, M., additional, Nelles, A., additional, Beck, R., additional, Falcke, H., additional, Fender, R., additional, Hörandel, J., additional, Koopmans, L. V. E., additional, Mann, G., additional, Miley, G., additional, Röttgering, H., additional, Stappers, B. W., additional, Wijers, R. A. M. J., additional, Zaroubi, S., additional, van den Akker, M., additional, Alexov, A., additional, Anderson, J., additional, Anderson, K., additional, van Ardenne, A., additional, Arts, M., additional, Asgekar, A., additional, Avruch, I. M., additional, Batejat, F., additional, Bähren, L., additional, Bell, M. E., additional, Bell, M. R., additional, van Bemmel, I., additional, Bennema, P., additional, Bentum, M. J., additional, Bernardi, G., additional, Best, P., additional, Bîrzan, L., additional, Bonafede, A., additional, Boonstra, A.-J., additional, Braun, R., additional, Bregman, J., additional, Breitling, F., additional, van de Brink, R. H., additional, Broderick, J., additional, Broekema, P. C., additional, Brouw, W. N., additional, Brüggen, M., additional, Butcher, H. R., additional, van Cappellen, W., additional, Ciardi, B., additional, Coenen, T., additional, Conway, J., additional, Coolen, A., additional, Corstanje, A., additional, Damstra, S., additional, Davies, O., additional, Deller, A. T., additional, Dettmar, R.-J., additional, van Diepen, G., additional, Dijkstra, K., additional, Donker, P., additional, Doorduin, A., additional, Dromer, J., additional, Drost, M., additional, van Duin, A., additional, Eislöffel, J., additional, van Enst, J., additional, Ferrari, C., additional, Frieswijk, W., additional, Gankema, H., additional, Garrett, M. A., additional, de Gasperin, F., additional, Gerbers, M., additional, de Geus, E., additional, Grießmeier, J.-M., additional, Grit, T., additional, Gruppen, P., additional, Hamaker, J. P., additional, Hassall, T., additional, Hoeft, M., additional, Holties, H. A., additional, Horneffer, A., additional, van der Horst, A., additional, van Houwelingen, A., additional, Huijgen, A., additional, Iacobelli, M., additional, Intema, H., additional, Jackson, N., additional, Jelic, V., additional, de Jong, A., additional, Juette, E., additional, Kant, D., additional, Karastergiou, A., additional, Koers, A., additional, Kollen, H., additional, Kondratiev, V. I., additional, Kooistra, E., additional, Koopman, Y., additional, Koster, A., additional, Kuniyoshi, M., additional, Kramer, M., additional, Kuper, G., additional, Lambropoulos, P., additional, Law, C., additional, van Leeuwen, J., additional, Lemaitre, J., additional, Loose, M., additional, Maat, P., additional, Macario, G., additional, Markoff, S., additional, Masters, J., additional, McFadden, R. A., additional, McKay-Bukowski, D., additional, Meijering, H., additional, Meulman, H., additional, Mevius, M., additional, Middelberg, E., additional, Millenaar, R., additional, Miller-Jones, J. C. A., additional, Mohan, R. N., additional, Mol, J. D., additional, Morawietz, J., additional, Morganti, R., additional, Mulcahy, D. D., additional, Mulder, E., additional, Munk, H., additional, Nieuwenhuis, L., additional, van Nieuwpoort, R., additional, Noordam, J. E., additional, Norden, M., additional, Noutsos, A., additional, Offringa, A. R., additional, Olofsson, H., additional, Omar, A., additional, Orrú, E., additional, Overeem, R., additional, Paas, H., additional, Pandey-Pommier, M., additional, Pandey, V. N., additional, Pizzo, R., additional, Polatidis, A., additional, Rafferty, D., additional, Rawlings, S., additional, Reich, W., additional, de Reijer, J.-P., additional, Reitsma, J., additional, Renting, G. A., additional, Riemers, P., additional, Rol, E., additional, Romein, J. W., additional, Roosjen, J., additional, Ruiter, M., additional, Scaife, A., additional, van der Schaaf, K., additional, Scheers, B., additional, Schellart, P., additional, Schoenmakers, A., additional, Schoonderbeek, G., additional, Serylak, M., additional, Shulevski, A., additional, Sluman, J., additional, Smirnov, O., additional, Sobey, C., additional, Spreeuw, H., additional, Steinmetz, M., additional, Sterks, C. G. M., additional, Stiepel, H.-J., additional, Stuurwold, K., additional, Tagger, M., additional, Tang, Y., additional, Tasse, C., additional, Thomas, I., additional, Thoudam, S., additional, Toribio, M. C., additional, van der Tol, B., additional, Usov, O., additional, van Veelen, M., additional, van der Veen, A.-J., additional, ter Veen, S., additional, Verbiest, J. P. W., additional, Vermeulen, R., additional, Vermaas, N., additional, Vocks, C., additional, Vogt, C., additional, de Vos, M., additional, van der Wal, E., additional, van Weeren, R., additional, Weggemans, H., additional, Weltevrede, P., additional, White, S., additional, Wijnholds, S. J., additional, Wilhelmsson, T., additional, Wucknitz, O., additional, Yatawatta, S., additional, Zarka, P., additional, Zensus, A., additional, and van Zwieten, J., additional

Published
2013
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162. The Lunar Cherenkov Technique: From Parkes Onwards

Author

James, C. W., Ekers, R. D., McFadden, R. A., Protheroe, R. J., James, C. W., Ekers, R. D., McFadden, R. A., and Protheroe, R. J.

Abstract

The lunar Cherenkov technique, which aims to detect the coherent Cherenkov radiation produced when UHE particles interact in the lunar regolith, was first attempted with the Parkes radio-telescope in 1995, though the theory was not sufficiently developed at this time to calculate a limit on the UHE neutrino flux from the non-observation. Since then, the technique has evolved to include experiments utilising lower frequencies, wider bandwidths, and entire arrays of antenna. We develop a simulation to analyse the full range of experiments, and calculate the UHE neutrino flux limit from the Parkes experiment, including the directional dependence. Our results suggest a methodology for planning future observations, and demonstrate how to utilise all available information on the nature of radio pulses from the Moon for the detection of UHE particles., Comment: 5 pages, 5 figures; Proceedings from 30th ICRC, Merida, Mexico, 2007 (4 pages in proceedings)

Published
2007

163. Towards Mg-β-NMR resonance linewidths adequate for applications in magnesium chemistry.

Author

Stachura, M., McFadden, R., Chatzichristos, A., Dehn, M., Gottberg, A., Hemmingsen, L., Jancso, A., Karner, V., Kiefl, R., Larsen, F., Lassen, J., Levy, C., Li, R., MacFarlane, W., Morris, G., Pallada, S., Pearson, M., Szunyogh, D., Thulstrup, P., and Voss, A.

Subjects
*NUCLEAR magnetic resonance, *MAGNESIUM, *METALLOPROTEINS, *LORENTZIAN function, *RESONANCE
Published
2017
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164. Development of a polarized Mg beam as a spin-1/2 probe for BNMR.

Author

Levy, C., Pearson, M., Dehn, M., Karner, V., Kiefl, R., Lassen, J., Li, R., MacFarlane, W., McFadden, R., Morris, G., Stachura, M., Teigelhöfer, A., and Voss, A.

Subjects
MAGNESIUM ions, SPIN-half particle, PROTON beams, MAGNESIUM oxide, NUCLEAR magnetic resonance spectroscopy
Abstract

A 28 keV beam of Mg ions was extracted from a uranium carbide, proton-beam-irradiated target coupled to a laser ion source. The ion beam was nuclear-spin polarized by collinear optical pumping on the $^{2}\textit {S}_{1/2}$ - $^{2}\textit {P}_{1/2}$ transition at 280 nm. The polarization was preserved by an extended 1 mT guide field as the beam was transported via electrostatic bends into a 2.5 T longitudinal magnetic field. There the beam was implanted into a single crystal MgO target and the beta decay asymmetry was measured. Both hyperfine ground states were optically pumped with a single frequency light source, using segmentation of the beam energy, which boosted the polarization by approximately 50 % compared to pumping a single ground state. The total decay asymmetry of 0.06 and beam intensity were sufficient to provide a useful spin-1/2 beam for future BNMR experiments. A variant of the method was used previously to optically pump the full Doppler-broadened absorption profile of a beam of Be with a single-frequency light source. [ABSTRACT FROM AUTHOR]

Published
2016
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166. LUNASKA neutrino search with the Parkes and ATCA telescopes

Author

Bray, J. D., primary, Ekers, R. D., additional, Protheroe, R. J., additional, James, C. W., additional, Phillips, C. J., additional, Roberts, P., additional, Brown, A., additional, Reynolds, J. E., additional, McFadden, R. A., additional, and Aartsen, M., additional

Published
2013
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167. Low-k interconnect stack with metal-insulator-metal capacitors for 22nm high volume manufacturing

Author

Ingerly, D., primary, Agrawal, A., additional, Ascazubi, R., additional, Blattner, A., additional, Buehler, M., additional, Chikarmane, V., additional, Choudhury, B., additional, Cinnor, F., additional, Ege, C., additional, Ganpule, C., additional, Glassman, T., additional, Grover, R., additional, Hentges, P., additional, Hicks, J., additional, Jones, D., additional, Kandas, A., additional, Khan, H., additional, Lazo, N., additional, Lee, K. S., additional, Liu, H., additional, Madhavan, A., additional, McFadden, R., additional, Mule, T., additional, Parsons, D., additional, Parthangal, P., additional, Rangaraj, S., additional, Rao, D., additional, Roesler, J., additional, Schmitz, A., additional, Sharma, M., additional, Shin, J., additional, Shusterman, Y., additional, Speer, N., additional, Tiwari, P., additional, Wang, G., additional, Yashar, P., additional, and Mistry, K., additional

Published
2012
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168. A 22nm high performance and low-power CMOS technology featuring fully-depleted tri-gate transistors, self-aligned contacts and high density MIM capacitors

Author

Auth, C., primary, Allen, C., additional, Blattner, A., additional, Bergstrom, D., additional, Brazier, M., additional, Bost, M., additional, Buehler, M., additional, Chikarmane, V., additional, Ghani, T., additional, Glassman, T., additional, Grover, R., additional, Han, W., additional, Hanken, D., additional, Hattendorf, M., additional, Hentges, P., additional, Heussner, R., additional, Hicks, J., additional, Ingerly, D., additional, Jain, P., additional, Jaloviar, S., additional, James, R., additional, Jones, D., additional, Jopling, J., additional, Joshi, S., additional, Kenyon, C., additional, Liu, H., additional, McFadden, R., additional, McIntyre, B., additional, Neirynck, J., additional, Parker, C., additional, Pipes, L., additional, Post, I., additional, Pradhan, S., additional, Prince, M., additional, Ramey, S., additional, Reynolds, T., additional, Roesler, J., additional, Sandford, J., additional, Seiple, J., additional, Smith, P., additional, Thomas, C., additional, Towner, D., additional, Troeger, T., additional, Weber, C., additional, Yashar, P., additional, Zawadzki, K., additional, and Mistry, K., additional

Published
2012
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169. Optimized trigger for ultra-high-energy cosmic-ray and neutrino observations with the low frequency radio array

Author

Singh, K., primary, Mevius, M., additional, Scholten, O., additional, Anderson, J.M., additional, van Ardenne, A., additional, Arts, M., additional, Avruch, M., additional, Asgekar, A., additional, Bell, M., additional, Bennema, P., additional, Bentum, M., additional, Bernadi, G., additional, Best, P., additional, Boonstra, A.-J., additional, Bregman, J., additional, van de Brink, R., additional, Broekema, C., additional, Brouw, W., additional, Brueggen, M., additional, Buitink, S., additional, Butcher, H., additional, van Cappellen, W., additional, Ciardi, B., additional, Coolen, A., additional, Damstra, S., additional, Dettmar, R., additional, van Diepen, G., additional, Dijkstra, K., additional, Donker, P., additional, Doorduin, A., additional, Drost, M., additional, van Duin, A., additional, Eisloeffel, J., additional, Falcke, H., additional, Garrett, M., additional, Gerbers, M., additional, Grießmeier, J.-M., additional, Grit, T., additional, Gruppen, P., additional, Gunst, A., additional, van Haarlem, M., additional, Hoeft, M., additional, Holties, H., additional, Hörandel, J., additional, Horneffer, L.A., additional, Huijgen, A., additional, James, C., additional, de Jong, A., additional, Kant, D., additional, Kooistra, E., additional, Koopman, Y., additional, Koopmans, L., additional, Kuper, G., additional, Lambropoulos, P., additional, van Leeuwen, J., additional, Loose, M., additional, Maat, P., additional, Mallary, C., additional, McFadden, R., additional, Meulman, H., additional, Mol, J.-D., additional, Morawietz, J., additional, Mulder, E., additional, Munk, H., additional, Nieuwenhuis, L., additional, Nijboer, R., additional, Norden, M.J., additional, Noordam, J., additional, Overeem, R., additional, Paas, H., additional, Pandey, V.N., additional, Pandey-Pommier, M., additional, Pizzo, R., additional, Polatidis, A., additional, Reich, W., additional, de Reijer, J., additional, Renting, A., additional, Riemers, P., additional, Roettgering, H., additional, Romein, J., additional, Roosjen, J., additional, Ruiter, M., additional, Schoenmakers, A., additional, Schoonderbeek, G., additional, Sluman, J., additional, Smirnov, O., additional, Stappers, B., additional, Steinmetz, M., additional, Stiepel, H., additional, Stuurwold, K., additional, Tagger, M., additional, Tang, Y., additional, ter Veen, S., additional, Vermeulen, R., additional, de Vos, M., additional, Vogt, C., additional, van der Wal, E., additional, Weggemans, H., additional, Wijnholds, S., additional, Wise, M., additional, Wucknitz, O., additional, Yattawatta, S., additional, and van Zwieten, J., additional

Published
2012
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170. Evidence for middle Eocene and younger land emergence in central Panama: Implications for Isthmus closure

Author

Montes, C., primary, Cardona, A., additional, McFadden, R., additional, Moron, S. E., additional, Silva, C. A., additional, Restrepo-Moreno, S., additional, Ramirez, D. A., additional, Hoyos, N., additional, Wilson, J., additional, Farris, D., additional, Bayona, G. A., additional, Jaramillo, C. A., additional, Valencia, V., additional, Bryan, J., additional, and Flores, J. A., additional

Published
2012
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171. Detecting ultra high energy neutrinos with LOFAR

Author

Mevius, M., primary, Buitink, S., additional, Falcke, H., additional, Hörandel, J., additional, James, C.W., additional, McFadden, R., additional, Scholten, O., additional, Singh, K., additional, Stappers, B., additional, and ter Veen, S., additional

Published
2012
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180. A large light-mass component of cosmic rays at 1017–1017.5electronvolts from radio observations

Author

Buitink, S., Corstanje, A., Falcke, H., Hörandel, J. R., Huege, T., Nelles, A., Rachen, J. P., Rossetto, L., Schellart, P., Scholten, O., ter Veen, S., Thoudam, S., Trinh, T. N. G., Anderson, J., Asgekar, A., Avruch, I. M., Bell, M. E., Bentum, M. J., Bernardi, G., Best, P., Bonafede, A., Breitling, F., Broderick, J. W., Brouw, W. N., Brüggen, M., Butcher, H. R., Carbone, D., Ciardi, B., Conway, J. E., de Gasperin, F., de Geus, E., Deller, A., Dettmar, R.-J., van Diepen, G., Duscha, S., Eislöffel, J., Engels, D., Enriquez, J. E., Fallows, R. A., Fender, R., Ferrari, C., Frieswijk, W., Garrett, M. A., Grießmeier, J. M., Gunst, A. W., van Haarlem, M. P., Hassall, T. E., Heald, G., Hessels, J. W. T., Hoeft, M., Horneffer, A., Iacobelli, M., Intema, H., Juette, E., Karastergiou, A., Kondratiev, V. I., Kramer, M., Kuniyoshi, M., Kuper, G., van Leeuwen, J., Loose, G. M., Maat, P., Mann, G., Markoff, S., McFadden, R., McKay-Bukowski, D., McKean, J. P., Mevius, M., Mulcahy, D. D., Munk, H., Norden, M. J., Orru, E., Paas, H., Pandey-Pommier, M., Pandey, V. N., Pietka, M., Pizzo, R., Polatidis, A. G., Reich, W., Röttgering, H. J. A., Scaife, A. M. M., Schwarz, D. J., Serylak, M., Sluman, J., Smirnov, O., Stappers, B. W., Steinmetz, M., Stewart, A., Swinbank, J., Tagger, M., Tang, Y., Tasse, C., Toribio, M. C., Vermeulen, R., Vocks, C., Vogt, C., van Weeren, R. J., Wijers, R. A. M. J., Wijnholds, S. J., Wise, M. W., Wucknitz, O., Yatawatta, S., Zarka, P., and Zensus, J. A.

Abstract

High-resolution radio measurements of air showers—cascades of secondary particles in the atmosphere initiated by cosmic rays—reveal that cosmic rays with energies of 1017–1017.5electronvolts have a mixed composition, with light elements (protons and helium nuclei) making up 80 per cent of their mass.

Published
2016
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184. When Does f-1 = 1/f?

Author

Cheng, R., primary, Dasgupta, A., additional, Ebanks, B. R., additional, Kinch, L. F., additional, Larson, L. M., additional, and McFadden, R. B., additional

Published
1998
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189. High vitamin D3 diet administered during active colitis negatively affects bone metabolism in an adoptive T cell transfer model.

Author

Larmonier, C. B., McFadden, R.-M. T., Hill, F. M., Schreiner, R., Ramalingam, R., Besselsen, D. G., Ghishan, F. K., and Kiela, P. R.

Subjects
*VITAMIN D content of food, *COLITIS, *BONE metabolism, *T cells, *CELL transformation, *INFLAMMATORY bowel diseases, *BONE resorption
Abstract

Decreased bone mineral density (BMD) represents an extraintestinal complication of inflammatory bowel disease (IBD). Vitamin D3 has been considered a viable adjunctive therapy in IBD. However, vitamin D3 plays a pleiotropic role in bone modeling and regulates the bone formation-resorption balance, depending on the physiological environment, and supplementation during active IBD may have unintended consequences. We evaluated the effects of vitamin D3 supplementation during the active phase of disease on colonic inflammation, BMD, and bone metabolism in an adoptive IL-10-/- CD4+ T cell transfer model of chronic colitis. High-dose vitamin D3 supplementation for 12 days during established disease had negligible effects on mucosal inflammation. Plasma vitamin D3 metabolites correlated with diet, but not disease, status. Colitis significantly reduced BMD. High-dose vitamin D3 supplementation did not affect cortical bone but led to a further deterioration of trabecular bone morphology. In mice fed a high vitamin D3 diet, colitis more severely impacted bone formation markers (osteocalcin and bone alkaline phosphatase) and increased bone resorption markers, ratio of receptor activator of NF-B ligand to osteoprotegrin transcript, plasma osteoprotegrin level, and the osteoclast activation marker tartrate-resistant acid phosphatase (ACp5). Bone vitamin D receptor expression was increased in mice with chronic colitis, especially in the high vitamin D3 group. Our data suggest that vitamin D3, at a dose that does not improve inflammation, has no beneficial effects on bone metabolism and density during active colitis or may adversely affect BMD and bone turnover. These observations should be taken into consideration in the planning of further clinical studies with high-dose vitamin D3 supplementation in patients with active IBD. [ABSTRACT FROM AUTHOR]

Published
2013
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190. LUNASKA experiment observational limits on UHE neutrinos from Centaurus A and the Galactic Centre.

Author

James, C. W., Protheroe, R. J., Ekers, R. D., Alvarez-Muñiz, J., McFadden, R. A., Phillips, C. J., Roberts, P., and Bray, J. D.

Subjects
NEUTRINOS, ACTIVE galaxies, GALACTIC nuclei, LARGE astronomical telescopes, DARK matter, COSMIC rays
Abstract

ABSTRACT We present the first observational limits to the ultra-high-energy (UHE) neutrino flux from the Galactic Centre, and from Centaurus A which is the nearest active galactic nucleus. These results are based on our 'Lunar UHE Neutrino Astrophysics using the Square Kilometre Array' (LUNASKA) project experiments at the Australia Telescope Compact Array (ATCA). We also derive limits for the previous experiments and compare these limits with expectations for acceleration and superheavy dark matter models of the origin of UHE cosmic rays. [ABSTRACT FROM AUTHOR]

Published
2011
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191. Oblique dilation, melt transfer, and gneiss dome emplacement.

Author

McFadden, R. R., Teyssier, C., Siddoway, C. S., Whitney, D. L., and Fanning, C. M.

Subjects
*GNEISS, *CRYSTALLIZATION, *CRETACEOUS stratigraphic geology, *MAGMATISM, *CRUST of the earth
Abstract

The upward transfer of partially molten crust and the formation of gneiss domes and metamorphic core complexes commonly take place by localization of normal or oblique extension in the middle and upper crust. In Marie Byrd Land, Antarctica, a transition from wrench to oblique extension occurred during oblique plate divergence along the East Gondwana margin and intracontinental crustal extension associated with the West Antarctic Rift System in mid-Cretaceous time. Migmatites in the Fosdick dome record steep fabrics formed during wrenching, and associated granite networks display crystallization ages of 117-115 Ma. These steep fabrics are overprinted by subhorizontal foliation and leucogranite sheets with crystallization ages in the 109-102 Ma range. Syntectonic emplacement of granite sheets in the South Fosdick detachment zone indicates that detachment tectonics led to rapid exhumation of the terrain by 100 Ma. This study has implications for understanding melt transport, magma accumulation, and the formation of detachments in an oblique tectonic setting. [ABSTRACT FROM AUTHOR]

Published
2010
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193. Effect of transjugular intrahepatic portosystemic shunt on thrombocytopenia associated with cirrhosis.

Author

Karasu, Zeki, Gurakar, Ahmet, Kerwin, Barbara, Hulagu, Saadettin, Jazzar, Ahmad, Mcfadden, Robert, Nour, Bakr, Sebastian, Anthony, Cassidy, Francis, Stokes, Kenneth, Van Thiel, David, Wright, Harlan, Karasu, Z, Gurakar, A, Kerwin, B, Hulagu, S, Jazzar, A, McFadden, R, Nour, B, and Sebastian, A

Abstract

Thrombocytopenia is a frequent complication of cirrhosis. Its pathogenesis is not well known, but it has been suggested that splenic congestion induced by portal hypertension may be a major contributory factor. However, the available data regarding the effect of portal decompression either by surgical shunts or transjugular intrahepatic portosystemic shunt (TIPS) on peripheral platelet count in cirrhotics is conflicting. We studied the effects of TIPS on platelet count and mean platelet volume, following a successful TIPS placement. The platelet count had a tendency to decrease but was not statistically significant (120,100 +/- 72,100/mm3 before TIPS vs 99,800 +/- 51,400/mm3 after TIPS). The mean platelet volume remained essentially unchanged (9.8 +/- 1.5 fL before TIPS and 9.9 +/- 1.5 fL after TIPS). These results confirm that TIPS has an unpredictable effect on platelet count in cirrhotic patients with thrombocytopenia. The lack of a consistent increase in the peripheral mean platelet volume following TIPS placement suggests that TIPS is unable to significantly enhance the release of platelets sequestered in the splenic compartment in portal hypertension. [ABSTRACT FROM AUTHOR]

Published
2000
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194. Pericardial Effusion Associated with Pancreatitis.

Author

Sassaris, M., McFadden, R., Woods, M., and Hunter, F.

Subjects
PANCREATITIS, HEART diseases, EXUDATES & transudates, INFLAMMATION, PANCREATIC diseases, PEOPLE with alcoholism
Abstract

Pericardial effusion associated with pancreatitis is rare. We describe a case of recurrent pancreatitis complicated by pancreatic pseudocyst and pleural and pericardial effusion in an alcohol abuser. [ABSTRACT FROM AUTHOR]

Published
1981

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