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4. VA Budgetary Shortfall Threatens Veteran Benefits

Author

Nicholson, R. James

Subjects
United States. Senate. Committee on Veterans' Affairs -- Powers and duties, United States. Department of Veterans Affairs -- Government finance, Budget deficits -- Laws, regulations and rules, Government regulation, Business, international
Abstract

Overview As Congress shifts from negotiating positions on appropriations bills to building a continuing resolution (CR) for the rest of the calendar year, the Department of Veterans' Affairs (VA) has [...]

Published
2024

5. The impact of star cluster environments on planet formation

Author

Nicholson, R., Parker, R., Habergham-Mawson, S., and James, P.

Subjects
523.4, QB Astronomy, QC Physics
Abstract

It is thought that most stars, including our Sun, form within clusters alongside many other stars. Planet formation and star formation occur simultaneously, and therefore the birth environment of stars will shape the formation of planets. Properties of the present day Solar System hint to a past in which the Sun formed in the presence of many other stars. There is an intrinsic interest in knowing the birthplace of the only known planetary system hosting life within the Universe and whether conditions of the birth environment are common or atypical. Understanding the origin of the Solar System could provide important constraints on star and planet formation. Observations of the present day Solar System have revealed a conflict between the need for a large cluster containing massive stars so that disc enrichment can occur and to explain the orbits and enrichment levels of some objects within the Solar System, and the need for a low-mass, quiescent cluster where dynamical and radiative effects will not disrupt or disperse planet forming discs. Low-mass clusters containing massive stars may present a solution to this problem. The presence of massive stars within star-forming regions will affect planet forming discs to varying degrees, depending on the initial conditions of the region. How the initial conditions of star-forming regions change the relationship between massive stars and protoplanetary discs is unknown. This thesis focuses on how the birth environment of stars can shape planet formation. The processes behind star formation, planet formation, and the impacts that star-forming regions can have on the formation of planets are reviewed. This thesis reviews what is currently known about the birth environment of the Sun based on evidence found within the Solar System and what this tells us. In this thesis, I show that low-mass star-forming regions containing one or two massive stars are viable environments for creating enriched planet forming discs that resemble the levels of enrichment found in the Solar System. These unusual clusters enrich planet forming discs at a similar rate to more massive (>1000 Mₒ) clusters. Based on the percentage of stars enriched by Supernovae within low-mass clusters, and the percentage of low-mass clusters containing massive stars in comparison to more massive clusters, it is possible that a significant number of unperturbed, enriched stars have been produced within these star-forming environments. However, the UV radiation produced by massive stars within low-mass clusters is still strong enough to cause protoplanetary discs to disperse on short timescales, potentially inhibiting planet formation. I find that the rate at which protoplanetary discs are dispersed depends on the initial conditions of the cluster and the location of the massive stars. The mass of the cluster, if massive stars are present, does not significantly alter the rate at which planet forming discs are dispersed. The initial density of the cluster is the most important aspect to consider. The background UV field produced by star-forming regions also varies depending on the initial spatial stellar profile. Planet forming discs within simulations that represent the initial conditions of nearby star-forming regions show that planet forming discs are dispersed on short (~1-3 Myr) time-scales. This means on of three things; either the majority of planets form in low-mass star-forming regions, giant planet formation must occur on very short timescales, or the current calculations of mass-loss in discs due to external photoevaporation severely overestimate the detrimental effects of EUV and FUV radiation. By calculating the UV background field in star-forming regions, I find that the initial spatial distribution of stars greatly affects the amount of UV radiation that stars receive. Delaying the effects of UV radiation by 0.5 Myr, to replicate the effects of delaying massive star formation, still results in vastly different UV field strengths. The types of stars that produce UV radiation are not limited to massive (≥15 Mₒ) stars, and lower mass (3 < M < 15 Mₒ) stars contribute large enough UV fields to potentially affect protoplanetary discs. This thesis has shown that the environment in which protoplanetary discs are born can dictate and strongly shape their evolution. The constraints on the birth environment of the Solar System have been relaxed, and the importance of considering the initial conditions of the star-forming region have been highlighted.

Published
2019
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6. Water immobilization by glass microspheres affects biological activity.

Author

Marangoni, A, Al-Abdul-Wahid, M, Nicholson, R, Roma, A, Gravelle, A, De Souza, J, Barbut, S, and Spagnuolo, P

Subjects
Cell Line, Tumor, Escherichia coli, Germination, Glass, Humans, Leukemia, Lymphoma, Microspheres, Seeds, Water
Abstract

We recently reported that the water holding capacity of myofibrillar protein hydrogels could be increased upon addition of small amounts of microparticles, particularly glass microspheres. Glass microspheres were found to decrease the spin-spin relaxation time (T2) of water protons in the gels, which was interpreted as enhanced water binding by the glass. We were thus interested in determining whether the observed effects on water proton relaxation were a direct consequence of water-glass interactions. Here we show how glass microspheres reduce the mobility of pure water, reflected in large decreases in the T2 of water protons, decreases in the self-diffusion coefficient of water molecules, a lower water activity, and strengthening of O-H bonds. Even though glass is considered an inert material, glass microspheres were shown to inhibit the growth of human embryonic kidney cells, and stimulate or inhibit the growth of leukemia and monocytic lymphoma cells in vitro, depending on dose and time. The germination of alfalfa seeds and the growth of E.coli cells were also inhibited upon exposure to glass microspheres. This work indicates that the properties and behavior of materials, even ones considered inert, can be affected by their size. These observations suggest possible toxicological consequences of exposure to microparticles, but also open us possibilities to affect cellular/organism function via modulation of macromolecular hydration.

Published
2018

8. Pion contamination in the MICE muon beam

Author

Adams, D., Alekou, A., Apollonio, M., Asfandiyarov, R., Barber, G., Barclay, P., de Bari, A., Bayes, R., Bayliss, V., Bertoni, R., Blackmore, V. J., Blondel, A., Blot, S., Bogomilov, M., Bonesini, M., Booth, C. N., Bowring, D., Boyd, S., Bradshaw, T. W., Bravar, U., Bross, A. D., Capponi, M., Carlisle, T., Cecchet, G., Charnley, C., Chignoli, F., Cline, D., Cobb, J. H., Colling, G., Collomb, N., Coney, L., Cooke, P., Courthold, M., Cremaldi, L. M., DeMello, A., Dick, A., Dobbs, A., Dornan, P., Drews, M., Drielsma, F., Filthaut, F., Fitzpatrick, T., Franchini, P., Francis, V., Fry, L., Gallagher, A., Gamet, R., Gardener, R., Gourlay, S., Grant, A., Greis, J. R., Griffiths, S., Hanlet, P., Hansen, O. M., Hanson, G. G., Hart, T. L., Hartnett, T., Hayler, T., Heidt, C., Hills, M., Hodgson, P., Hunt, C., Iaciofano, A., Ishimoto, S., Kafka, G., Kaplan, D. M., Karadzhov, Y., Kim, Y. K., Kuno, Y., Kyberd, P., Lagrange, J-B, Langlands, J., Lau, W., Leonova, M., Li, D., Lintern, A., Littlefield, M., Long, K., Luo, T., Macwaters, C., Martlew, B., Martyniak, J., Mazza, R., Middleton, S., Moretti, A., Moss, A., Muir, A., Mullacrane, I., Nebrensky, J. J., Neuffer, D., Nichols, A., Nicholson, R., Nugent, J. C., Oates, A., Onel, Y., Orestano, D., Overton, E., Owens, P., Palladino, V., Pasternak, J., Pastore, F., Pidcott, C., Popovic, M., Preece, R., Prestemon, S., Rajaram, D., Ramberger, S., Rayner, M. A., Ricciardi, S., Roberts, T. J., Robinson, M., Rogers, C., Ronald, K., Rubinov, P., Rucinski, P., Sakamato, H., Sanders, D. A., Santos, E., Savidge, T., Smith, P. J., Snopok, P., Soler, F. J. P., Speirs, D., Stanley, T., Stokes, G., Summers, D. J., Tarrant, J., Taylor, I., Tortora, L., Torun, Y., Tsenov, R., Tunnell, C. D., Uchida, M. A., Vankova-Kirilova, G., Virostek, S., Vretenar, M., Warburton, P., Watson, S., White, C., Whyte, C. G., Wilson, A., Winter, M., Yang, X., Young, A., and Zisman, M.

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract

The international Muon Ionization Cooling Experiment (MICE) will perform a systematic investigation of ionization cooling with muon beams of momentum between 140 and 240\,MeV/c at the Rutherford Appleton Laboratory ISIS facility. The measurement of ionization cooling in MICE relies on the selection of a pure sample of muons that traverse the experiment. To make this selection, the MICE Muon Beam is designed to deliver a beam of muons with less than $\sim$1\% contamination. To make the final muon selection, MICE employs a particle-identification (PID) system upstream and downstream of the cooling cell. The PID system includes time-of-flight hodoscopes, threshold-Cherenkov counters and calorimetry. The upper limit for the pion contamination measured in this paper is $f_\pi < 1.4\%$ at 90\% C.L., including systematic uncertainties. Therefore, the MICE Muon Beam is able to meet the stringent pion-contamination requirements of the study of ionization cooling., Comment: 16 pages, 7 figures

Published
2015
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9. Electron-Muon Ranger: performance in the MICE Muon Beam

Author

Adams, D., Alekou, A., Apollonio, M., Asfandiyarov, R., Barber, G., Barclay, P., de Bari, A., Bayes, R., Bayliss, V., Bene, P., Bertoni, R., Blackmore, V. J., Blondel, A., Blot, S., Bogomilov, M., Bonesini, M., Booth, C. N., Bowring, D., Boyd, S., Bradshaw, T. W., Bravar, U., Bross, A. D., Cadoux, F., Capponi, M., Carlisle, T., Cecchet, G., Charnley, C., Chignoli, F., Cline, D., Cobb, J. H., Colling, G., Collomb, N., Coney, L., Cooke, P., Courthold, M., Cremaldi, L. M., Debieux, S., DeMello, A., Dick, A., Dobbs, A., Dornan, P., Drielsma, F., Filthaut, F., Fitzpatrick, T., Franchini, P., Francis, V., Fry, L., Gallagher, A., Gamet, R., Gardener, R., Gourlay, S., Grant, A., Graulich, J. S., Greis, J., Griffiths, S., Hanlet, P., Hansen, O. M., Hanson, G. G., Hart, T. L., Hartnett, T., Hayler, T., Heidt, C., Hills, M., Hodgson, P., Hunt, C., Husi, C., Iaciofano, A., Ishimoto, S., Kafka, G., Kaplan, D. M., Karadzhov, Y., Kim, Y. K., Kuno, Y., Kyberd, P., Lagrange, J-B, Langlands, J., Lau, W., Leonova, M., Li, D., Lintern, A., Littlefield, M., Long, K., Luo, T., Macwaters, C., Martlew, B., Martyniak, J., Masciocchi, F., Mazza, R., Middleton, S., Moretti, A., Moss, A., Muir, A., Mullacrane, I., Nebrensky, J. J., Neuffer, D., Nichols, A., Nicholson, R., Nicola, L., Messomo, E. Noah, Nugent, J. C., Oates, A., Onel, Y., Orestano, D., Overton, E., Owens, P., Palladino, V., Pasternak, J., Pastore, F., Pidcott, C., Popovic, M., Preece, R., Prestemon, S., Rajaram, D., Ramberger, S., Rayner, M. A., Ricciardi, S., Roberts, T. J., Robinson, M., Rogers, C., Ronald, K., Rothenfusser, K., Rubinov, P., Rucinski, P., Sakamato, H., Sanders, D. A., Sandstrom, R., Santos, E., Savidge, T., Smith, P. J., Snopok, P., Soler, F. J. P., Speirs, D., Stanley, T., Stokes, G., Summers, D. J., Tarrant, J., Taylor, I., Tortora, L., Torun, Y., Tsenov, R., Tunnell, C. D., Uchida, M. A., Vankova-Kirilova, G., Virostek, S., Vretenar, M., Warburton, P., Watson, S., White, C., Whyte, C. G., Wilson, A., Wisting, H., Yang, X., Young, A., and Zisman, M.

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract

The Muon Ionization Cooling Experiment (MICE) will perform a detailed study of ionization cooling to evaluate the feasibility of the technique. To carry out this program, MICE requires an efficient particle-identification (PID) system to identify muons. The Electron-Muon Ranger (EMR) is a fully-active tracking-calorimeter that forms part of the PID system and tags muons that traverse the cooling channel without decaying. The detector is capable of identifying electrons with an efficiency of 98.6%, providing a purity for the MICE beam that exceeds 99.8%. The EMR also proved to be a powerful tool for the reconstruction of muon momenta in the range 100-280 MeV/$c$., Comment: 22 pages, 19 figures

Published
2015
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13. Pion contamination in the MICE muon beam

Author

Adams, D, Alekou, A, Apollonio, M, Asfandiyarov, R, Barber, G, Barclay, P, de Bari, A, Bayes, R, Bayliss, V, Bertoni, R, Blackmore, VJ, Blondel, A, Blot, S, Bogomilov, M, Bonesini, M, Booth, CN, Bowring, D, Boyd, S, Brashaw, TW, Bravar, U, Bross, AD, Capponi, M, Carlisle, T, Cecchet, G, Charnley, C, Chignoli, F, Cline, D, Cobb, JH, Colling, G, Collomb, N, Coney, L, Cooke, P, Courthold, M, Cremaldi, LM, DeMello, A, Dick, A, Dobbs, A, Dornan, P, Drews, M, Drielsma, F, Filthaut, F, Fitzpatrick, T, Franchini, P, Francis, V, Fry, L, Gallagher, A, Gamet, R, Gardener, R, Gourlay, S, Grant, A, Greis, JR, Griffiths, S, Hanlet, P, Hansen, OM, Hanson, GG, Hart, TL, Hartnett, T, Hayler, T, Heidt, C, Hills, M, Hodgson, P, Hunt, C, Iaciofano, A, Ishimoto, S, Kafka, G, Kaplan, DM, Karadzhov, Y, Kim, YK, Kuno, Y, Kyberd, P, Lagrange, J-B, Langlands, J, Lau, W, Leonova, M, Li, D, Lintern, A, Littlefield, M, Long, K, Luo, T, Macwaters, C, Martlew, B, Martyniak, J, Mazza, R, Middleton, S, Moretti, A, Moss, A, Muir, A, Mullacrane, I, Nebrensky, JJ, Neuffer, D, Nichols, A, Nicholson, R, Nugent, JC, Oates, A, Onel, Y, Orestano, D, Overton, E, Owens, P, Palladino, V, and Pasternak, J

Subjects
Nuclear and Plasma Physics, Particle and High Energy Physics, Synchrotrons and Accelerators, Physical Sciences, Instrumentation for particle accelerators and storage rings - low energy, Beam-line instrumentation (beam position and profile, monitors, beam-intensity monitors, bunch length monitors), physics.ins-det, hep-ex, Engineering, Nuclear & Particles Physics, Physical sciences
Abstract

The international Muon Ionization Cooling Experiment (MICE) will perform a systematic investigation of ionization cooling with muon beams of momentum between 140 and 240 MeV/c at the Rutherford Appleton Laboratory ISIS facility. The measurement of ionization cooling in MICE relies on the selection of a pure sample of muons that traverse the experiment. To make this selection, the MICE Muon Beam is designed to deliver a beam of muons with less than ∼1% contamination. To make the final muon selection, MICE employs a particle-identification (PID) system upstream and downstream of the cooling cell. The PID system includes time-of-flight hodoscopes, threshold-Cherenkov counters and calorimetry. The upper limit for the pion contamination measured in this paper is fπ < 1.4% at 90% C.L., including systematic uncertainties. Therefore, the MICE Muon Beam is able to meet the stringent pion-contamination requirements of the study of ionization cooling.

Published
2016

14. Electron-muon ranger: Performance in the MICE muon beam

Author

Adams, D, Alekou, A, Apollonio, M, Asfandiyarov, R, Barber, G, Barclay, P, De Bari, A, Bayes, R, Bayliss, V, Bene, P, Bertoni, R, Blackmore, VJ, Blondel, A, Blot, S, Bogomilov, M, Bonesini, M, Booth, CN, Bowring, D, Boyd, S, Bradshaw, TW, Bravar, U, Bross, AD, Cadoux, F, Capponi, M, Carlisle, T, Cecchet, G, Charnley, C, Chignoli, F, Cline, D, Cobb, JH, Colling, G, Collomb, N, Coney, L, Cooke, P, Courthold, M, Cremaldi, LM, Debieux, S, Demello, A, Dick, A, Dobbs, A, Dornan, P, Drielsma, F, Filthaut, F, Fitzpatrick, T, Franchini, P, Francis, V, Fry, L, Gallagher, A, Gamet, R, Gardener, R, Gourlay, S, Grant, A, Graulich, JS, Greis, J, Griffiths, S, Hanlet, P, Hansen, OM, Hanson, GG, Hart, TL, Hartnett, T, Hayler, T, Heidt, C, Hills, M, Hodgson, P, Hunt, C, Husi, C, Iaciofano, A, Ishimoto, S, Kafka, G, Kaplan, DM, Karadzhov, Y, Kim, YK, Kuno, Y, Kyberd, P, Lagrange, JB, Langlands, J, Lau, W, Leonova, M, Li, D, Lintern, A, Littlefield, M, Long, K, Luo, T, Macwaters, C, Martlew, B, Martyniak, J, Masciocchi, F, Mazza, R, Middleton, S, Moretti, A, Moss, A, Muir, A, Mullacrane, I, Nebrensky, JJ, Neuffer, D, Nichols, A, Nicholson, R, Nicola, L, Messomo, EN, and Nugent, JC

Subjects
Particle identification methods, Particle tracking detectors, Performance of High Energy Physics Detectors, Calorimeters, physics.ins-det, hep-ex, Nuclear & Particles Physics, Other Physical Sciences, Physical Sciences, Engineering
Abstract

The Muon Ionization Cooling Experiment (MICE) will perform a detailed study of ionization cooling to evaluate the feasibility of the technique. To carry out this program, MICE requires an efficient particle-identification (PID) system to identify muons. The Electron-Muon Ranger (EMR) is a fully-active tracking-calorimeter that forms part of the PID system and tags muons that traverse the cooling channel without decaying. The detector is capable of identifying electrons with an efficiency of 98.6%, providing a purity for the MICE beam that exceeds 99.8%. The EMR also proved to be a powerful tool for the reconstruction of muon momenta in the range 100-280 MeV/c.

Published
2015

16. Characterisation of the muon beams for the Muon Ionisation Cooling Experiment

Author

The MICE Collaboration, Adams, D., Adey, D., Alekou, A., Apollonio, M., Asfandiyarov, R., Back, J., Barber, G., Barclay, P., de Bari, A., Bayes, R., Bayliss, V., Bertoni, R., Blackmore, V. J., Blondel, A., Blot, S., Bogomilov, M., Bonesini, M., Booth, C. N., Bowring, D., Boyd, S., Bradshaw, T. W., Bravar, U., Bross, A. D., Capponi, M., Carlisle, T., Cecchet, G., Charnley, G., Cobb, J. H., Colling, D., Collomb, N., Coney, L., Cooke, P., Courthold, M., Cremaldi, L. M., DeMello, A., Dick, A., Dobbs, A., Dornan, P., Fayer, S., Filthaut, F., Fish, A., Fitzpatrick, T., Fletcher, R., Forrest, D., Francis, V., Freemire, B., Fry, L., Gallagher, A., Gamet, R., Gourlay, S., Grant, A., Graulich, J. S., Griffiths, S., Hanlet, P., Hansen, O. M., Hanson, G. G., Harrison, P., Hart, T. L., Hartnett, T., Hayler, T., Heidt, C., Hills, M., Hodgson, P., Iaciofano, A., Ishimoto, S., Kafka, G., Kaplan, D. M., Karadzhov, Y., Kim, Y. K., Kolev, D., Kuno, Y., Kyberd, P., Lau, W., Leaver, J., Leonova, M., Li, D., Lintern, A., Littlefield, M., Long, K., Lucchini, G., Luo, T., Macwaters, C., Martlew, B., Martyniak, J., Moretti, A., Moss, A., Muir, A., Mullacrane, I., Nebrensky, J. J., Neuffer, D., Nichols, A., Nicholson, R., Nugent, J. C., Onel, Y., Orestano, D., Overton, E., Owens, P., Palladino, V., Pasternak, J., Pastore, F., Pidcott, C., Popovic, M., Preece, R., Prestemon, S., Rajaram, D., Ramberger, S., Rayner, M. A., Ricciardi, S., Richards, A., Roberts, T. J., Robinson, M., Rogers, C., Ronald, K., Rubinov, P., Rucinski, R., Rusinov, I., Sakamoto, H., Sanders, D. A., Santos, E., Savidge, T., Smith, P. J., Snopok, P., Soler, F. J. P., Stanley, T., Summers, D. J., Takahashi, M., Tarrant, J., Taylor, I., Tortora, L., Torun, Y., Tsenov, R., Tunnell, C. D., Vankova, G., Verguilov, V., Virostek, S., Vretenar, M., Walaron, K., Watson, S., White, C., Whyte, C. G., Wilson, A., Wisting, H., and Zisman, M.

Subjects
Physics - Accelerator Physics
Abstract

A novel single-particle technique to measure emittance has been developed and used to characterise seventeen different muon beams for the Muon Ionisation Cooling Experiment (MICE). The muon beams, whose mean momenta vary from 171 to 281 MeV/c, have emittances of approximately 1.5--2.3 \pi mm-rad horizontally and 0.6--1.0 \pi mm-rad vertically, a horizontal dispersion of 90--190 mm and momentum spreads of about 25 MeV/c. There is reasonable agreement between the measured parameters of the beams and the results of simulations. The beams are found to meet the requirements of MICE., Comment: Published in EPJC, 20 pages, 15 figures

Published
2013
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17. The design, construction and performance of the MICE target

Author

Booth, C. N., Hodgson, P., Howlett, L., Nicholson, R., Overton, E., Robinson, M., Smith, P. J., Apollonio, M., Barber, G., Dobbs, A., Leaver, J., Long, K. R., Shepherd, B., Adams, D., Capocci, E., McCarron, E., and Tarrant, J.

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment, Physics - Accelerator Physics
Abstract

The pion-production target that serves the MICE Muon Beam consists of a titanium cylinder that is dipped into the halo of the ISIS proton beam. The design and construction of the MICE target system are described along with the quality-assurance procedures, electromagnetic drive and control systems, the readout electronics, and the data-acquisition system. The performance of the target is presented together with the particle rates delivered to the MICE Muon Beam. Finally, the beam loss in ISIS generated by the operation of the target is evaluated as a function of the particle rate, and the operating parameters of the target are derived., Comment: 58 pages and 49 figures. To be published in JINST

Published
2012
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18. MICE: the Muon Ionization Cooling Experiment. Step I: First Measurement of Emittance with Particle Physics Detectors

Author

Bravar, U., Bogomilov, M., Karadzhov, Y., Kolev, D., Russinov, I., Tsenov, R., Wang, L., Xu, F. Y., Zheng, S. X., Bertoni, R., Bonesini, M., Mazza, R., Palladino, V., Cecchet, G., de Bari, A., Capponi, M., Iaciofano, A., Orestano, D., Pastore, F., Tortora, L., Ishimoto, S., Suzuki, S., Yoshimura, K., Mori, Y., Kuno, Y., Sakamoto, H., Sato, A., Yano, T., Yoshida, M., Filthaut, F., Vretenar, M., Ramberger, S., Blondel, A., Cadoux, F., Masciocchi, F., Graulich, J. S., Verguilov, V., Wisting, H., Petitjean, C., Seviour, R., Ellis, M., Kyberd, P., Littlefield, M., Nebrensky, J. J., Forrest, D., Soler, F. J. P., Walaron, K., Cooke, P., Gamet, R., Alecou, A., Apollonio, M., Barber, G., Dobbs, A., Dornan, P., Fish, A., Hare, R., Jamdagni, A., Kasey, V., Khaleeq, M., Long, K., Pasternak, J., Sashalmi, T., Blackmore, V., Cobb, J., Lau, W., Rayner, M., Tunnell, C. D., Witte, H., Yang, S., Alexander, J., Charnley, G., Griffiths, S., Martlew, B., Moss, A., Mullacrane, I., Oats, A., York, S., Apsimon, R., Alexander, R. J., Barclay, P., Baynham, D. E., Bradshaw, T. W., Courthold, M., Hayler, R. Edgecock T., Hills, M., Jones, T., McCubbin, N., Murray, W. J., Nelson, C., Nicholls, A., Norton, P. R., Prior, C., Rochford, J. H., Rogers, C., Spensley, W., Tilley, K., Booth, C. N., Hodgson, P., Nicholson, R., Overton, E., Robinson, M., Smith, P., Adey, D., Back, J., Boyd, S., Harrison, P., Norem, J., Bross, A. D., Geer, S., Moretti, A., Neuffer, D., Popovic, M., Qian, Z., Raja, R., Stefanski, R., Cummings, M. A. C., Roberts, T. J., DeMello, A., Green, M. A., Li, D., Sessler, A. M., Virostek, S., Zisman, M. S., Freemire, B., Hanlet, P., Huang, D., Kafka, G., Kaplan, D. M., Snopok, P., Torun, Y., Onel, Y., Cline, D., Lee, K., Fukui, Y., Yang, X., Rimmer, R. A., Cremaldi, L. M., Hart, T. L., Summers, D. J., Coney, L., Fletcher, R., Hanson, G. G., Heidt, C., Gallardo, J., Kahn, S., Kirk, H., and Palmer, R. B.

Subjects
Physics - Accelerator Physics, High Energy Physics - Experiment
Abstract

The Muon Ionization Cooling Experiment (MICE) is a strategic R&D project intended to demonstrate the only practical solution to providing high brilliance beams necessary for a neutrino factory or muon collider. MICE is under development at the Rutherford Appleton Laboratory (RAL) in the United Kingdom. It comprises a dedicated beamline to generate a range of input muon emittances and momenta, with time-of-flight and Cherenkov detectors to ensure a pure muon beam. The emittance of the incoming beam will be measured in the upstream magnetic spectrometer with a scintillating fiber tracker. A cooling cell will then follow, alternating energy loss in Liquid Hydrogen (LH2) absorbers to RF cavity acceleration. A second spectrometer, identical to the first, and a second muon identification system will measure the outgoing emittance. In the 2010 run at RAL the muon beamline and most detectors were fully commissioned and a first measurement of the emittance of the muon beam with particle physics (time-of-flight) detectors was performed. The analysis of these data was recently completed and is discussed in this paper. Future steps for MICE, where beam emittance and emittance reduction (cooling) are to be measured with greater accuracy, are also presented., Comment: Proceedings of the DPF-2011 Conference, Providence, RI, August 8-13, 2011

Published
2011

19. ULTRACAM: an ultra-fast, triple-beam CCD camera for high-speed astrophysics

Author

Dhillon, V. S., Marsh, T. R., Stevenson, M. J., Atkinson, D. C., Kerry, P., Peacocke, P. T., Vick, A. J. A., Beard, S. M., Ives, D. J., Lunney, D. W., McLay, S. A., Tierney, C. J., Kelly, J., Littlefair, S. P., Nicholson, R., Pashley, R., Harlaftis, E. T., and O'Brien, K.

Subjects
Astrophysics
Abstract

ULTRACAM is a portable, high-speed imaging photometer designed to study faint astronomical objects at high temporal resolutions. ULTRACAM employs two dichroic beamsplitters and three frame-transfer CCD cameras to provide three-colour optical imaging at frame rates of up to 500 Hz. The instrument has been mounted on both the 4.2-m William Herschel Telescope on La Palma and the 8.2-m Very Large Telescope in Chile, and has been used to study white dwarfs, brown dwarfs, pulsars, black-hole/neutron-star X-ray binaries, gamma-ray bursts, cataclysmic variables, eclipsing binary stars, extrasolar planets, flare stars, ultra-compact binaries, active galactic nuclei, asteroseismology and occultations by Solar System objects (Titan, Pluto and Kuiper Belt objects). In this paper we describe the scientific motivation behind ULTRACAM, present an outline of its design and report on its measured performance., Comment: 17 pages, 7 figures, accepted for publication in MNRAS

Published
2007
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21. Characterisation of the muon beams for the Muon Ionisation Cooling Experiment

Author

Adams, D, Adey, D, Alekou, A, Apollonio, M, Asfandiyarov, R, Back, J, Barber, G, Barclay, P, de Bari, A, Bayes, R, Bayliss, V, Bertoni, R, Blackmore, VJ, Blondel, A, Blot, S, Bogomilov, M, Bonesini, M, Booth, CN, Bowring, D, Boyd, S, Bradshaw, TW, Bravar, U, Bross, AD, Capponi, M, Carlisle, T, Cecchet, G, Charnley, G, Cobb, JH, Colling, D, Collomb, N, Coney, L, Cooke, P, Courthold, M, Cremaldi, LM, DeMello, A, Dick, AJ, Dobbs, A, Dornan, P, Fayer, S, Filthaut, F, Fish, A, Fitzpatrick, T, Fletcher, R, Forrest, D, Francis, V, Freemire, B, Fry, L, Gallagher, A, Gamet, R, Gourlay, S, Grant, A, Graulich, JS, Griffiths, S, Hanlet, P, Hansen, OM, Hanson, GG, Harrison, P, Hart, TL, Hartnett, T, Hayler, T, Heidt, C, Hills, M, Hodgson, P, Hunt, C, Iaciofano, A, Ishimoto, S, Kafka, G, Kaplan, DM, Karadzhov, Y, Kim, YK, Kolev, D, Kuno, Y, Kyberd, P, Lau, W, Leaver, J, Leonova, M, Li, D, Lintern, A, Littlefield, M, Long, K, Lucchini, G, Luo, T, Macwaters, C, Martlew, B, Martyniak, J, Middleton, S, Moretti, A, Moss, A, Muir, A, Mullacrane, I, Nebrensky, JJ, Neuffer, D, Nichols, A, Nicholson, R, Nugent, JC, Onel, Y, Orestano, D, Overton, E, Owens, P, and Palladino, V

Subjects
physics.acc-ph, Nuclear & Particles Physics, Quantum Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics
Abstract

A novel single-particle technique to measure emittance has been developed and used to characterise seventeen different muon beams for the Muon Ionisation Cooling Experiment (MICE). The muon beams, whose mean momenta vary from 171 to 281 MeV/c, have emittances of approximately 1.2-2.3 π mm-rad horizontally and 0.6-1.0 π mm-rad vertically, a horizontal dispersion of 90-190 mm and momentum spreads of about 25 MeV/c. There is reasonable agreement between the measured parameters of the beams and the results of simulations. The beams are found to meet the requirements of MICE. © 2013 The Author(s).

Published
2013

28. To Void or Not to Void After Minimally Invasive Benign Hysterectomy: That Is the Question.

Author

LeNeveu, M, Davis, J, Nicholson, R, Leaf, MC, Musselman, K, Simpson, K, Wu, H, Wahab, M, Borahay, M, Wang, KC, Patzkowsky, K, and Frost, A

Abstract

Determine outcomes of strict versus liberal voiding following benign, minimally invasive (MIS), hysterectomy among same-day discharge patients. The primary outcome was difference in post-anesthesia care unit (PACU) time between groups. Secondary outcomes included time to void, rates of post-operative urinary retention (POUR), urinary tract infection (UTI), and emergency room (ER) visits. Single-blinded randomized controlled trial. Tertiary care academic medical center. Patients who underwent benign, MIS hysterectomy between December 2022 and February 2024. Patients were randomized 1:1 to the void (V) or no void (NV) arms. Excluded patients were those with prior urologic procedures, known urologic disease, any urologic indication for surgery, or combined surgery with another service. Patients in the NV arm were contacted on post-operative day (POD) #1, and all patients were contacted on POD#30. Rates of urinary dysfunction, ER visits, and UTI diagnosis were recorded. During the study period, 494 hysterectomies were performed; 369 were eligible, and 203 were included in the final analysis (102 V arm, 101 NV arm). Patients in the NV arm were discharged 27 minutes earlier than those in the V arm (p=0.002). There was no difference in time to void between those patients who voided in the NV arm, and patients in the V arm (p=0.404). Three patients were diagnosed with a UTI within 30-days of surgery, one in the V arm and two in the NV arm. Four patients (1.9%) had POUR post-operatively, 3 in the V arm and 1 in the NV arm; all were detected in the PACU prior to discharge. No patients re-presented for POUR. A liberal voiding policy after benign MIS hysterectomy resulted in significantly less time in PACU. Further studies should be conducted to confirm safety. [ABSTRACT FROM AUTHOR]

Published
2024
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34. Occupational Therapy, Physical Therapy, and Orientation and Mobility Services in Public Schools

Author

Neal, J, Bigby ,L, and Nicholson, R

Abstract

The related service areas of occupational therapy, physical therapy, and orientation and mobility share some areas of professional practice but are quite distinct in the way services allow children with disabilities to fully participate in contemporary school environments. This article presents an overview of the roles and responsibilities of professionals in these areas and how they offer their services to children with disabilities.

Published
2004

37. Reliable and efficient parameter estimation using approximate continuum limit descriptions of stochastic models

Author

Simpson, MJ, Baker, RE, Buenzli, PR, Nicholson, R, and Maclaren, OJ

Subjects
Statistics and Probability, Likelihood Functions, Stochastic Processes, General Immunology and Microbiology, Applied Mathematics, Modeling and Simulation, Humans, Computer Simulation, General Medicine, General Agricultural and Biological Sciences, Models, Biological, General Biochemistry, Genetics and Molecular Biology, Algorithms
Abstract

Stochastic individual-based mathematical models are attractive for modelling biological phenomena because they naturally capture the stochasticity and variability that is often evident in biological data. Such models also allow us to track the motion of individuals within the population of interest. Unfortunately, capturing this microscopic detail means that simulation and parameter inference can become computationally expensive. One approach for overcoming this computational limitation is to coarse-grain the stochastic model to provide an approximate continuum model that can be solved using far less computational effort. However, coarse-grained continuum models can be biased or inaccurate, particularly for certain parameter regimes. In this work, we combine stochastic and continuum mathematical models in the context of lattice-based models of two-dimensional cell biology experiments by demonstrating how to simulate two commonly used experiments: cell proliferation assays and barrier assays. Our approach involves building a simple statistical model of the discrepancy between the expensive stochastic model and the associated computationally inexpensive coarse-grained continuum model. We form this statistical model based on a limited number of expensive stochastic model evaluations at design points sampled from a user-chosen distribution, corresponding to a computer experiment design problem. With straightforward design point selection schemes, we show that using the statistical model of the discrepancy in tandem with the computationally inexpensive continuum model allows us to carry out prediction and inference while correcting for biases and inaccuracies due to the continuum approximation. We demonstrate this approach by simulating a proliferation assay, where the continuum limit model is the well-known logistic ordinary differential equation, as well as a barrier assay where the continuum limit model is closely related to the well-known Fisher-KPP partial differential equation. We construct an approximate likelihood function for parameter inference, both with and without discrepancy correction terms. Using maximum likelihood estimation, we provide point estimates of the unknown parameters, and use the profile likelihood to characterise the uncertainty in these estimates and form approximate confidence intervals. For the range of inference problems considered, working with the continuum limit model alone leads to biased parameter estimation and confidence intervals with poor coverage. In contrast, incorporating correction terms arising from the statistical model of the model discrepancy allows us to recover the parameters accurately with minimal computational overhead. The main tradeoff is that the associated confidence intervals are typically broader, reflecting the additional uncertainty introduced by the approximation process. All algorithms required to replicate the results in this work are written in the open source Julia language and are available at GitHub.

Published
2022

38. The Primary Use of Endocrine Therapies

Author

Howell, A., Anderson, E., Blamey, R., Clarke, R. B., Dixon, J. M., Dowsett, M., Johnston, S. R. D., Miller, W. R., Nicholson, R., Robertson, J. F. R., Schlag, P. M., editor, Senn, H.-J., editor, Diehl, V., editor, Parkin, D. M., editor, Rajewsky, M. F., editor, Rubens, R., editor, Wannenmacher, M., editor, Senn, Hans-Jörg, editor, Gelber, Richard D., editor, Goldhirsch, Aron, editor, and Thürlimann, Beat, editor

Published
1998
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42. Chief Executive Officers Contracts and Compensation, 1981: A Study of the Contract Provisions, Language, Benefits, and Compensation of Chief Executive Officers of Two-Year Colleges for the 1981 Year.

Author

American Association of Community and Junior Colleges, Washington, DC. Presidents Academy. and Nicholson, R. Stephen

Abstract

In June 1981, the Presidents Academy conducted a study of the contract and compensation arrangements for chief executive officers (CEO's) of two-year colleges in the United States and its territories and Canada. Responses were received from 639 of the 1,231 colleges surveyed; 90% were public colleges. The study revealed that: (1) 72% of the CEO's had a contract; (2) contract terms ranged from one to five years, with 26% being for one year; (3) 40.5% of the contracts provided for annual review; (4) only 2% of the contracts specified the basic duties of the CEO; and (5) 8% provided for evaluation. The mean salary of CEO's was $48,402.09, and a clear relationship was revealed between enrollment and salary. With regard to other benefits, 25% of the colleges provided a home or housing allowance; 61.2% offered health benefits; 43% provided family tuition benefits; 71% paid a travel allowance; and 70% offered life insurance. The mean benefits of CEO's amounted to $13,258. The study report considers findings in terms of regional and institutional size differences. It includes a discussion of factors influencing compensation and excerpts from CEO contracts which cover areas including appointment, term, reappointment, duties, extent of services, housing, automobile allowance, liability, retirement, sabbaticals, disability, documentation, evaluation, discharge, termination, vacation, moving expenses, and contract clarification. The survey instrument is appended. (HB)

Published
1981

43. Chief Executive Officers: Contracts and Compensation.

Author

American Association of Community and Junior Colleges, Washington, DC. Presidents Academy. and Nicholson, R. Stephen

Abstract

In 1986, a study was conducted of the employment contracts of the chief executive officers (CEO's) of two-year colleges in the United States, Canada, and Puerto Rico. Questionnaires were mailed to the entire membership of the American Association of Community and Junior Colleges, totaling 1,110 colleges. Study findings, based on responses from 506 CEO's, included the following: (1) a 3-year term was the most popular length for 1986 contracts, as opposed to the 1-year term which was most common in 1981; (2) contract renewal based on an annual review gained popularity between 1981 and 1986; (3) almost 6% of the contracts were expressed as board resolutions, 6% as standard professional or state contract forms, and 59% as formal contracts; (4) a board-initiated termination provision was present in 25% of the contracts, up from 10% in 1981; (5) average salaries ranged from $49,853 for colleges with 1,000 students or less to $76,628 for colleges with more than 20,001 students; (6) the mean annual salary was $62,949 in 1986, representing an increase of 30% over 1981's mean of $48,402; (7) average salaries were highest in the far western United States, and lowest in the mountain states; and (8) 14.7% of the colleges provided homes for their CEO's, 88.3% provided paid medical coverage, 27% offered spouse tuition benefits, 67% provided between 10 and 14 paid holidays per year, 48% offered between 21 and 25 paid vacation days, and 71% provided life insurance and travel allowances. (AYC)

Published
1988

44. Reconstructing the history of helminth prevalence in the UK

Author

Ryan, H, Flammer, PG, Nicholson, R, Loe, L, Reeves, B, Allison, E, Guy, C, Doriga, IL, Waldron, T, Walker, D, Kirchhelle, C, Larson, G, and Smith, AL

Subjects
Feces, Infectious Diseases, Diphyllobothrium, Helminths, Ascaris, Public Health, Environmental and Occupational Health, Helminthiasis, Prevalence, Animals, Intestinal Diseases, Parasitic, United Kingdom
Abstract

Intestinal helminth parasites (worms) have afflicted humans throughout history and their eggs are readily detected in archaeological deposits including at locations where intestinal parasites are no longer considered endemic (e.g. the UK). Parasites provide valuable archaeological insights into historical health, sanitation, hygiene, dietary and culinary practices, as well as other factors. Differences in the prevalence of helminths over time may help us understand factors that affected the rate of infection of these parasites in past populations. While communal deposits often contain relatively high numbers of parasite eggs, these cannot be used to calculate prevalence rates, which are a key epidemiological measure of infection. The prevalence of intestinal helminths was investigated through time in England, based on analysis of 464 human burials from 17 sites, dating from the Prehistoric to Industrial periods. Eggs from two faecal-oral transmitted nematodes (Ascaris sp. and Trichuris sp.) and the food-derived cestodes (Taenia spp. and Diphyllobothrium latum syn Dibothriocephalus latus) were identified, although only Ascaris was detected at a high frequency. The changing prevalence of nematode infections can be attributed to changes in effective sanitation or other factors that affect these faecal-oral transmitted parasites and the presence of cestode infections reflect dietary and culinary preferences. These results indicate that the impact of helminth infections on past populations varied over time, and that some locations witnessed a dramatic reduction in parasite prevalence during the industrial era (18th-19th century), whereas other locations continued to experience high prevalence levels. The factors underlying these reductions and the variation in prevalence provide a key historical context for modern anthelmintic programs.

Published
2021

46. A Study of Public Two-Year College Organizational Structure and Development of Technical Curricula. Final Report.

Author

Nicholson, R. Stephen

Abstract

This study examines the organization of public 2-year colleges and relates it with goal achievement as represented by curriculum size and complexity. The research questions concerned: (1) range and distribution of size and age in the colleges; (2) range and distribution of curriculum size and complexity; (3) the relation of increased size or age to an increase in curriculum size or complexity; (4) range and distribution of faculty size in relation to size and age of the college; (5) any regional differences in size, age, and curriculum; (6) range and distribution of administrative size and of centralized curriculum control; (7) range and distribution of departmentalization and operational levels; (8) relationship between administrative size, centralized curriculum control, and curriculum size and complexity; (9) relationship between operational levels, departmentalization, and curriculum size and complexity. The findings provide suggestions for answering the questions, but also post other questions for exploration and the development of hypotheses to be tested. (HH)

Published
1971

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