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1. On-deck seismology: Lessons from InSight for future planetary seismology

Author

Panning, Mark P., Pike, W. Tom, Lognonné, Philippe, Banerdt, W. Bruce, Murdoch, Naomi, Banfield, Don, Charalambous, Constantinos, Kedar, Sharon, Lorenz, Ralph D., Marusiak, Angela G., McClean, John B., Nunn, Ceri, Stähler, Simon C., Stott, Alexander E., and Warren, Tristram

Subjects
Physics - Geophysics, Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

Before deploying to the surface of Mars, the short-period (SP) seismometer of the InSight mission operated on deck for a total of 48 hours. This dataset can be used to understand how deck-mounted seismometers can be used in future landed missions to Mars, Europa, and other planetary bodies. While operating on deck, the SP seismometer showed signals comparable to the Viking-2 seismometer near 3 Hz where the sensitivity of the Viking instrument peaked. Wind sensitivity showed similar patterns to the Viking instrument, although amplitudes on InSight were ~80% larger for a given wind velocity. However, during the low wind evening hours the instrument noise levels at frequencies between 0.1 and 1 Hz were comparable to quiet stations on Earth, although deployment to the surface below the Wind and Thermal Shield lowered installation noise by roughly 40 dB in acceleration power. With the observed noise levels and estimated seismicity rates for Mars, detection probability for quakes for a deck-mounted instrument are low enough that up to years of on-deck recordings may be necessary to observe an event. Because the noise is dominated by wind acting on the lander, though, deck-mounted seismometers may be more practical for deployment on airless bodies, and it is important to evaluate the seismicity of the target body and the specific design of the lander. Detection probabilities for operation on Europa reach over 99% for some proposed seismicity models for a similar duration of operation if noise levels are comparable to low-wind time periods on Mars., Comment: 20 pages, 7 figures, accepted to Journal of Geophysical Research: Planets

Published
2020
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4. The marsquake catalogue from InSight, sols 0–1011

Author

Ceylan, Savas, Clinton, John F., Giardini, Domenico, Stähler, Simon C., Horleston, Anna, Kawamura, Taichi, Böse, Maren, Charalambous, Constantinos, Dahmen, Nikolaj L., van Driel, Martin, Durán, Cecilia, Euchner, Fabian, Khan, Amir, Kim, Doyeon, Plasman, Matthieu, Scholz, John-Robert, Zenhäusern, Géraldine, Beucler, Eric, Garcia, Raphaël F., Kedar, Sharon, Knapmeyer, Martin, Lognonné, Philippe, Panning, Mark P., Perrin, Clément, Pike, William T., Stott, Alexander E., and Banerdt, William B.

Published
2022
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5. Simultaneous diagonalisation of the covariance and complementary covariance matrices in quaternion widely linear signal processing

Author

Xiang, Min, Enshaeifar, Shirin, Stott, Alexander E., Took, Clive Cheong, Xia, Yili, Kanna, Sithan, and Mandic, Danilo P.

Subjects
Computer Science - Numerical Analysis, Computer Science - Information Theory
Abstract

Recent developments in quaternion-valued widely linear processing have established that the exploitation of complete second-order statistics requires consideration of both the standard covariance and the three complementary covariance matrices. Although such matrices have a tremendous amount of structure and their decomposition is a powerful tool in a variety of applications, the non-commutative nature of the quaternion product has been prohibitive to the development of quaternion uncorrelating transforms. To this end, we introduce novel techniques for a simultaneous decomposition of the covariance and complementary covariance matrices in the quaternion domain, whereby the quaternion version of the Takagi factorisation is explored to diagonalise symmetric quaternion-valued matrices. This gives new insights into the quaternion uncorrelating transform (QUT) and forms a basis for the proposed quaternion approximate uncorrelating transform (QAUT) which simultaneously diagonalises all four covariance matrices associated with improper quaternion signals. The effectiveness of the proposed uncorrelating transforms is validated by simulations on both synthetic and real-world quaternion-valued signals., Comment: 41 pages, single column, 10 figures

Published
2017

6. The sound of a Martian dust devil

Author

Murdoch, N., Stott, A. E., Gillier, M., Hueso, R., Lemmon, M., Martinez, G., Apéstigue, V., Toledo, D., Lorenz, R. D., Chide, B., Munguira, A., Sánchez-Lavega, A., Vicente-Retortillo, A., Newman, C. E., Maurice, S., de la Torre Juárez, M., Bertrand, T., Banfield, D., Navarro, S., Marin, M., Torres, J., Gomez-Elvira, J., Jacob, X., Cadu, A., Sournac, A., Rodriguez-Manfredi, J. A., Wiens, R. C., and Mimoun, D.

Published
2022
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7. Seismic constraints from a Mars impact experiment using InSight and Perseverance

Author

Fernando, Benjamin, Wójcicka, Natalia, Maguire, Ross, Stähler, Simon C., Stott, Alexander E., Ceylan, Savas, Charalambous, Constantinos, Clinton, John, Collins, Gareth S., Dahmen, Nikolaj, Froment, Marouchka, Golombek, Matthew, Horleston, Anna, Karatekin, Ozgur, Kawamura, Taichi, Larmat, Carene, Nissen-Meyer, Tarje, Patel, Manish R., Plasman, Matthieu, Posiolova, Lilya, Rolland, Lucie, Spiga, Aymeric, Teanby, Nicholas A., Zenhäusern, Géraldine, Giardini, Domenico, Lognonné, Philippe, Banerdt, Bruce, and Daubar, Ingrid J.

Published
2022
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8. Companion guide to the marsquake catalog from InSight, Sols 0–478: Data content and non-seismic events

Author

Ceylan, Savas, Clinton, John F., Giardini, Domenico, Böse, Maren, Charalambous, Constantinos, Driel, Martin van, Horleston, Anna, Kawamura, Taichi, Khan, Amir, Orhand-Mainsant, Guenolé, Scholz, John-Robert, Stähler, Simon C., Euchner, Fabian, Banerdt, William B., Lognonné, Philippe, Banfield, Don, Beucler, Eric, Garcia, Raphaël F., Kedar, Sharon, Panning, Mark P., Pike, William T., Smrekar, Suzanne E., Spiga, Aymeric, Dahmen, Nikolaj L., Hurst, Kenneth, Stott, Alexander E., Lorenz, Ralph D., Schimmel, Martin, Stutzmann, Eléonore, Pierick, Jan ten, Conejero, Vincent, Pardo, Constanza, and Perrin, Clément

Published
2021
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9. The Marsquake catalogue from InSight, sols 0–478

Author

Clinton, John F., Ceylan, Savas, van Driel, Martin, Giardini, Domenico, Stähler, Simon C., Böse, Maren, Charalambous, Constantinos, Dahmen, Nikolaj L., Horleston, Anna, Kawamura, Taichi, Khan, Amir, Orhand-Mainsant, Guenolé, Scholz, John-Robert, Euchner, Fabian, Banerdt, William B., Lognonné, Philippe, Banfield, Don, Beucler, Eric, Garcia, Raphaël F., Kedar, Sharon, Panning, Mark P., Perrin, Clement, Pike, William T., Smrekar, Suzanne E., Spiga, Aymeric, and Stott, Alexander E.

Published
2021
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13. The atmosphere of Mars as observed by InSight

Author

Banfield, Don, Spiga, Aymeric, Newman, Claire, Forget, François, Lemmon, Mark, Lorenz, Ralph, Murdoch, Naomi, Viudez-Moreiras, Daniel, Pla-Garcia, Jorge, Garcia, Raphaël F., Lognonné, Philippe, Karatekin, Özgür, Perrin, Clément, Martire, Léo, Teanby, Nicholas, Hove, Bart Van, Maki, Justin N., Kenda, Balthasar, Mueller, Nils T., Rodriguez, Sébastien, Kawamura, Taichi, McClean, John B., Stott, Alexander E., Charalambous, Constantinos, Millour, Ehouarn, Johnson, Catherine L., Mittelholz, Anna, Määttänen, Anni, Lewis, Stephen R., Clinton, John, Stähler, Simon C., Ceylan, Savas, Giardini, Domenico, Warren, Tristram, Pike, William T., Daubar, Ingrid, Golombek, Matthew, Rolland, Lucie, Widmer-Schnidrig, Rudolf, Mimoun, David, Beucler, Éric, Jacob, Alice, Lucas, Antoine, Baker, Mariah, Ansan, Véronique, Hurst, Kenneth, Mora-Sotomayor, Luis, Navarro, Sara, Torres, Josefina, Lepinette, Alain, Molina, Antonio, Marin-Jimenez, Mercedes, Gomez-Elvira, Javier, Peinado, Veronica, Rodriguez-Manfredi, Jose-Antonio, Carcich, Brian T., Sackett, Stephen, Russell, Christopher T., Spohn, Tilman, Smrekar, Suzanne E., and Banerdt, W. Bruce

Published
2020
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14. The seismicity of Mars

Author

Giardini, D., Lognonné, P., Banerdt, W. B., Pike, W. T., Christensen, U., Ceylan, S., Clinton, J. F., van Driel, M., Stähler, S. C., Böse, M., Garcia, R. F., Khan, A., Panning, M., Perrin, C., Banfield, D., Beucler, E., Charalambous, C., Euchner, F., Horleston, A., Jacob, A., Kawamura, T., Kedar, S., Mainsant, G., Scholz, J.-R., Smrekar, S. E., Spiga, A., Agard, C., Antonangeli, D., Barkaoui, S., Barrett, E., Combes, P., Conejero, V., Daubar, I., Drilleau, M., Ferrier, C., Gabsi, T., Gudkova, T., Hurst, K., Karakostas, F., King, S., Knapmeyer, M., Knapmeyer-Endrun, B., Llorca-Cejudo, R., Lucas, A., Luno, L., Margerin, L., McClean, J. B., Mimoun, D., Murdoch, N., Nimmo, F., Nonon, M., Pardo, C., Rivoldini, A., Manfredi, J. A. Rodriguez, Samuel, H., Schimmel, M., Stott, A. E., Stutzmann, E., Teanby, N., Warren, T., Weber, R. C., Wieczorek, M., and Yana, C.

Published
2020
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16. An acoustic investigation of the near-surface turbulence on Mars

Author

Chide, Baptiste, primary, Blanc-Benon, Philippe, additional, Bertrand, Tanguy, additional, Jacob, Xavier, additional, Lasue, Jérémie, additional, Lorenz, Ralph D., additional, Montmessin, Franck, additional, Murdoch, Naomi, additional, Pla-Garcia, Jorge, additional, Seel, Fabian, additional, Schröder, Susanne, additional, Stott, Alexander E., additional, de la Torre Juarez, Manuel, additional, and Wiens, Roger C., additional

Published
2024
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18. Acoustic Propagation in the Near‐Surface Martian Atmosphere.

Author

Gillier, Martin, Petculescu, Andi, Stott, Alexander E., Murdoch, Naomi, Jacob, Xavier, Chide, Baptiste, Maurice, Sylvestre, and Mimoun, David

Subjects
ATMOSPHERIC acoustics, MARTIAN atmosphere, MARTIAN surface, ACOUSTIC wave propagation, ACOUSTIC field, ATMOSPHERIC turbulence
Abstract

This work introduces a comprehensive model of sound propagation on Mars, in light of the recent operation of several microphones on the Martian surface. The main outcome of this work is an operational acoustic model capable of simulating the sound field created by any source, at any location on the Martian surface, at any time. Expanding on the result of previous work (Gillier et al., 2024, https://doi.org/10.1029/2023je008257), we use the parabolic equation method for sound propagation in order to obtain the overall sound field produced by a source, in a given atmospheric composition and state, and accounting for ground properties. The resulting model enables the study of acoustics on Mars, and has the potential also to be used to probe the properties of the Martian environment using acoustic measurements with known sources. We investigate the effects of the Martian ground and the vertical profile of temperature and wind, on sound propagation. We find that the ground has a minor effect on sound propagation, and the wind profile strongly influences sound propagation as on Earth. However, the midday near surface temperature profiles on Mars are shown to cause refraction, which generates non‐negligible acoustic losses that are an order of magnitude stronger than typical refraction‐related acoustic losses on Earth. We show that the effect of the Martian atmospheric turbulence is to slightly reduce the acoustic losses due to refraction. Finally, we apply our model to show that refraction and atmospheric turbulence have a negligible effect on the propagation of sound from Ingenuity to the Perseverance rover. Plain Language Summary: Sound provides new ways for exploring the Martian environment. Whether to examine the characteristics of sound sources on Mars or to infer atmospheric properties from the behavior of sound waves in the Martian atmosphere, an accurate model of sound propagation on Mars is needed. This model must account for the path traveled by the sound waves in the atmosphere as well as their interactions with the planet's surface. We propose a model that allows us to compute the sound that would be received by a microphone depending on its relative position to a source given a set of atmospheric conditions. We investigate the effects of the ground, the vertical gradient of temperature and the wind speed, as well as the effects of atmospheric turbulence. We find that, because of the strong temperature gradient at noon on Mars, sound is bent upwards creating a quieter zone close to the ground. This effect also occurs on Earth, but is much stronger on Mars. The main outcome of this work is a model that can simulate the sound field created by any source for any location at the Martian surface at any time of year and any time of day. Key Points: We have developed a model to compute the sound field created by a specific sound source at any time and place near the Martian surfaceModel predictions show that the main parameters affecting sound propagation are the temperature and wind speed profilesRefraction and atmospheric turbulence have a small effect on acoustic waves at the altitude of the Ingenuity rotorcraft [ABSTRACT FROM AUTHOR]

Published
2024
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19. Organic thin film transistors : integration challenges

Author

Stott, J. E.

Subjects
621.3
Abstract

This thesis considers some of the requirements and challenges in the eld of organic thin lm transistors (OTFTs), from the standpoint of large scale integration using low temperature plastic compatible processes. A combination of processes and materials for use in the fabrication of OTFTs is developed, yielding device performance comparable with the state of the art for bottom-contact, bottom-gate, organic small molecule thin lm transistors. High quality silicon nitride (SiNx) gate dielectric material is developed using plasma enhanced chemical vapour deposition (PECVD) at a low temperature (150 C) compatible with plastic substrates. A variety of high quality lms are developed, allowing an investigation into the impact of changes in SiNx composition on OTFT performance. Surface modi cation strategies on SiNx substrates are considered, leading to almost an order of magnitude enhancement in OTFT performance, suggesting a suitable device architecture for large scale integration, and exploitation of novel organic material properties. We then examine organic semiconductor nanowire devices, which have begun to emerge as a new and exciting class of device in recent years. This work explores the possibilities of combining traditional thin lm transistor fabrication techniques with novel organic nanowires and examines the resultant transistor device behaviour. Two-dimensional arrays of nanowire devices are analysed, demonstrating the suitability of devices for large area applications. The combination of a large area and plastic compatible, low temperature dielectric with well known organic semiconductors in thin lm devices suggests that the integration of novel organic nanowires could provide an exciting performance enhancement over traditional OTFT devices.

Published
2013

22. Student pro-sociality: Measuring institutional and individual factors that predict pro-social behaviour at university

Author

Stiff, Chris, Rosenthal-Stott, Harriet E. S., Wake, Stephanie, and Woodward, Amelia

Subjects
Measurement, Surveys
Abstract

Author(s): Chris Stiff [sup.1] , Harriet E. S. Rosenthal-Stott [sup.2] , Stephanie Wake [sup.3] , Amelia Woodward [sup.1] Author Affiliations: (Aff1) 0000 0004 0415 6205, grid.9757.c, School of Psychology, Keele [...], Students operate within a bounded social context and often face decisions regarding whether to pursue selfish or group-level benefit. Yet little work has examined what predicts their behaviour towards fellow students. This work addresses this gap by investigating what factors may predict students' performance of pro-social actions at university, and how an institution may maximise such behaviour. Study 1 created the student pro-sociality scale, used to measure these tendencies in students. In study 2, 428 students from 25 UK universities took part an online survey study using this scale, and several other pre-existing measures of possible predictors. Analysis suggested that of those factors examined, role clarity, affective commitment, empathy, and perspective-taking emerged as the most influential. This first foray into this area can now inspire further research in finding the effective ways of fostering pro-social behaviour in students.

Published
2019
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23. Planetary Seismology: Nearly 3 years on Mars, and a return to the Moon

Author

Yana, Charles, Weber, Renee, Walsh, William, Standley, Ian, de Raucourt, Sebastien, Pont, Gabriel, Pike, W. Tom, Nunn, Ceri, Lognonné, Philippe, Kawamura, Taichi, Garcia, Raphael, Elliott, John, Cutler, James, Calcutt, Simon, Bugby, David, Bowles, Neil, Kedar, Sharon, Tharimena, S, Tauzin, B, Stutzmann, E, Schimmel, M, Schmelzbach, C, Nunn, C, Murdoch, N, Lekic, V, Brinkman, N, Kenda, B, Fayon, L, Spiga, A, Stott, A. E, Stähler, S, Orhand-Mainsant, G, Knapmeyer, M, Khan, A, Horleston, A, van Driel, M, Charalambous, C, Ceylan, S, Böse, M, Drilleau, M, Hurst, K, Weber, R, Teanby, N, Schmerr, N, Mimoun, D, Margerin, L, Knapmeyer-Endrun, B, Kedar, S, Kawamura, T, Irving, J, Garcia, R, Clinton, J, Bozdag, E, Lorenz, R, Giardini, D, Pike, W.T, Lognonné, P, Banerdt, W.B, and Panning, Mark

Published
2021

24. Planetary Seismology: Nearly 3 years on Mars, and a return to the Moon

Author

Panning, Mark, Banerdt, W.B, Lognonné, P, Pike, W.T, Giardini, D, Lorenz, R, Bozdag, E, Clinton, J, Garcia, R, Irving, J, Kawamura, T, Kedar, S, Knapmeyer-Endrun, B, Margerin, L, Mimoun, D, Schmerr, N, Teanby, N, Weber, R, Hurst, K, Drilleau, M, Böse, M, Ceylan, S, Charalambous, C, van Driel, M, Horleston, A, Khan, A, Knapmeyer, M, Orhand-Mainsant, G, Stähler, S, Stott, A. E, Spiga, A, Fayon, L, Kenda, B, Brinkman, N, Lekic, V, Murdoch, N, Nunn, C, Schmelzbach, C, Schimmel, M, Stutzmann, E, Tauzin, B, Tharimena, S, Kedar, Sharon, Bowles, Neil, Bugby, David, Calcutt, Simon, Cutler, James, Elliott, John, Garcia, Raphael, Kawamura, Taichi, Lognonné, Philippe, Nunn, Ceri, Pike, W. Tom, Pont, Gabriel, de Raucourt, Sebastien, Standley, Ian, Walsh, William, Weber, Renee, and Yana, Charles

Published
2021

27. Investigating Diurnal and Seasonal Turbulence Variations of the Martian Atmosphere Using a Spectral Approach

Author

Murdoch, Naomi, primary, Stott, Alexander E., additional, Mimoun, David, additional, Pinot, Baptiste, additional, Chatain, Audrey, additional, Spiga, Aymeric, additional, Temel, Orkun, additional, Garcia, Jorge Pla, additional, Onodera, Keisuke, additional, Lorenz, Ralph, additional, Gillier, Martin, additional, Newman, Claire, additional, Garcia, Raphael F., additional, Lange, Lucas, additional, and Banfield, Don, additional

Published
2023
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28. Prognosis Discussion and Referral to Community Palliative Care Services in Patients with Advanced Pancreatic Cancer Treated in a Tertiary Cancer Centre

Author

Clelland, Sarah, primary, Nuttall, Christina L., additional, Stott, Helen E., additional, Cope, Joseph, additional, Barratt, Natalie L., additional, Farrell, Kelly, additional, Eyong, Manyi V., additional, Gleeson, Jack P., additional, Lamarca, Angela, additional, Hubner, Richard A., additional, Valle, Juan W., additional, and McNamara, Mairéad G., additional

Published
2023
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29. Pharmacodynamics of ATI-2307 in a rabbit model of cryptococcal meningoencephalitis

Author

Giamberardino, Charles D., primary, Tenor, Jennifer L., additional, Toffaletti, Dena L., additional, Palmucci, Julia R., additional, Schell, Wiley, additional, Boua, Jane-Valeriane K., additional, Marius, Choiselle, additional, Stott, Katharine E., additional, Steele, Shelby L., additional, Hope, William, additional, Cilla, Don, additional, and Perfect, John R., additional

Published
2023
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31. The Response of Higher-Achieving South African Learners from Poverty to an Extracurricular Mathematics-guided Problem-based Learning Programme.

Author

Stott, Angela E. and Duvenhage, Monique

Subjects
*PROBLEM-based learning, *POOR communities, *MATHEMATICAL programming, *VIDEO recording, DEVELOPING countries
Abstract

Problem-based learning (PBL) has the potential to enhance both cognitive and affective engagement but has been criticised for being unsuitable for learners with low levels of knowledge and skills, such as South African learners from poor backgrounds. In such cases, guided problem-based learning (GPBL), which includes direct instruction and teacher prompting, may be more effective. However, little is known about the extent to which GPBL can replicate the cognitive and affective benefits of PBL for such learners in the context of middle-school mathematics problem-solving. It is also not clear what the optimal granularity of teacher prompting should be within GPBL. To address these issues, this instrumental case study was conducted with 26 higher-achieving Grade 8 and 9 learners from schools serving poor communities. These learners participated in a GPBL week-long extracurricular holiday mathematics programme in which they were guided to use trigonometry to determine the maximum height reached by a water rocket. Data were collected through video recordings, field notes, written work, and audio-recorded group discussions, and were coded using the multidimensional problem-solving (MPS) framework to identify cognitive and affective behaviors. The learners' affective responses suggested general positivity towards effortful problem-solving. Their cognitive responses suggested successful engagement in some, but not all, aspects of problem-solving. Although fine-grained prompting did not promote exploratory discussion, it was found to be necessary to guide productive mathematical activity. Medium-grained prompting, which did lead to exploratory discussion, did not appear to be directly productive, although it did appear to enhance learners' receptivity to subsequent fine-grained prompting. [ABSTRACT FROM AUTHOR]

Published
2024
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35. Potassium delivery to rivers : a case study of the Gara catchment, Devon

Author

Stott, Rachel E.

Subjects
363.738, Solute delivery, Slapton catchments
Abstract

Potassium is one of the three most important elements in fertiliser, but in comparison to the mobile anions nitrate and phosphate, there has been little study of its transport within drainage basins. Potassium is a monovalent cation that sorbs strongly to soil constituents; leaching losses are expected to be minimal. However, data from a variety of catchments indicate that concentrations of dissolved potassium increase up to ten-fold during storm events, suggesting that leaching does occur. Possible sources of potassium are vegetation, the soil, mobilised sediment on the hillslope and sediment within the river channel. Previous work has only considered vegetation as a source. Field data at three scales: the hillslope, first-order subcatchment and fourth-order catchment, are used to investigate the sources of potassium and the mechanisms involved during transport from the hillslope to the drainage basin outlet. The drainage basin studied is that of the River Gara, near Slapton in south west Devon, UK. A temporally and spatially intensive sampling programme of mobile and immobile soil waters at the hillslope scale was conducted during storm events in the winter of 1995-6. At this scale, old water that has been resident in the soil for some time is of higher potassium concentration than new water (precipitation inputs for that storm). Discharge of such water to the surface as return flow is particularly significant in potassium transport. The subcatchment response during storm events is consistent with these observations: maximum potassium concentrations occur at the same time as old water contributes to the storm hydrograph. Vegetation and mobilised sediment on the hillslope are demonstrated to increase the potassium concentration of overland flow, but the relative significance of these two mechanisms could not be assessed. Fertiliser applications of potassium are efficiently retained within the soil; no changes in the subcatchment response are apparent after a fertiliser application. At the catchment scale, the maximum potassium concentrations during storm events occurred at the same time as new water contributed to the storm hydrograph. This response is not consistent with the hillslope and subcatchment response. It is interpreted to indicate that the link between potassium transport from the hillslope to the basin outlet is complex, with storages and sinks of potassium reducing the significance of hillslope-scale processes in the catchment response. Suspended sediment within the river channel is demonstrated to contribute to the increase in potassium concentrations during storm events, although they do not account for all of the increase. An alternative explanation is that the land use of the subcatchment differs from that of the whole catchment. The percentage of land put to arable crops in the subcatchment was higher than in the whole catchment; this is likely to reduce the potassium concentration of overland flow (composed of new water), since organic material is more evenly distributed throughout the soil profile in this case. An autumn increase in potassium concentrations has previously been observed; this has been attributed to autumn leaf fall. Experimental data indicate that potassium lost from fallen leaves is efficiently retained within the soil. Weekly data from two gauging stations of Slapton Ley Field Centre (1987-1996) display a highly variable potassium response, and demonstrate no seasonal trend.

Published
1997

36. Correction to: AMBIsome Therapy Induction OptimisatioN (AMBITION): High Dose AmBisome for Cryptococcal Meningitis Induction Therapy in sub-Saharan Africa: Study Protocol for a Phase 3 Randomised Controlled Non-Inferiority Trial

Author

Lawrence, David S., Youssouf, Nabila, Molloy, Síle F., Alanio, Alexandre, Alufandika, Melanie, Boulware, David R., Boyer-Chammard, Timothée, Chen, Tao, Dromer, Francoise, Hlupeni, Admire, Hope, William, Hosseinipour, Mina C., Kanyama, Cecilia, Lortholary, Oliver, Loyse, Angela, Meya, David B., Mosepele, Mosepele, Muzoora, Conrad, Mwandumba, Henry C., Ndhlovu, Chiratidzo E., Niessen, Louis, Schutz, Charlotte, Stott, Katharine E., Wang, Duolao, Lalloo, David G., Meintjes, Graeme, Jaffar, Shabbar, Harrison, Thomas S., and Jarvis, Joseph N.

Published
2019
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37. Machine learning and marsquakes: a tool to predict atmospheric-seismic noise for the NASA InSight mission

Author

Stott, A. E., Garcia, R. F., Chedozeau, A., Spiga, A., Murdoch, N., Pinot, B., Mimoun, D., Charalambous, C., Horleston, A., King, Scott D., Kawamura, T., Dahmen, N., Barkaoui, S., Lognonne, P., Banerdt, W. B., Stott, A. E., Garcia, R. F., Chedozeau, A., Spiga, A., Murdoch, N., Pinot, B., Mimoun, D., Charalambous, C., Horleston, A., King, Scott D., Kawamura, T., Dahmen, N., Barkaoui, S., Lognonne, P., and Banerdt, W. B.

Abstract

The SEIS (seismic experiment for the interior structure of Mars) experiment on the NASA InSight mission has catalogued hundreds of marsquakes so far. However, the detectability of these events is controlled by the weather which generates noise on the seismometer. This affects the catalogue on both diurnal and seasonal scales. We propose to use machine learning methods to fit the wind, pressure and temperature data to the seismic energy recorded in the 0.4–1 and 2.2–2.6 Hz bandwidths to examine low- (LF) and high-frequency (HF) seismic event categories respectively. We implement Gaussian process regression and neural network models for this task. This approach provides the relationship between the atmospheric state and seismic energy. The obtained seismic energy estimate is used to calculate signal-to-noise ratios (SNR) of marsquakes for multiple bandwidths. We can then demonstrate the presence of LF energy above the noise level during several events predominantly categorized as HF, suggesting a continuum in event spectra distribution across the marsquake types. We introduce an algorithm to detect marsquakes based on the subtraction of the predicted noise from the observed data. This algorithm finds 39 previously undetected marsquakes, with another 40 possible candidates. Furthermore, an analysis of the detection algorithm’s variable threshold provides an empirical estimate of marsquake detectivity. This suggests that events producing the largest signal on the seismometer would be seen almost all the time, the median size signal event 45–50 per cent of the time and smallest signal events 5−20 per cent of the time.

Published
2023

38. Nocturnal Turbulence at Jezero Crater as Determined From MEDA Measurements and Modeling

Author

Física aplicada I, Fisika aplikatua I, Plá García, Jorge, Munguira Ruiz, Asier, Rafkin, Scot, Newman, Claire E., Bertrand, Tanguy, Martínez, Germán, Hueso Alonso, Ricardo, Sánchez Lavega, Agustín María, Del Río Gaztelurrutia, María Teresa, Stott, Alexander E., Murdoch, Naomi, de la Torre Juárez, Manuel, Lemmon, Mark T., Chide, Baptiste, Viúdez Moreiras, Daniel, Savijärvi, Hannu, Richardson, Mark I., Marín Jiménez, Mercedes, Sebastián, Eduardo, Lepinette, Alain, Mora Sotomayor, Luis, Rodríguez Manfredi, José Antonio, Física aplicada I, Fisika aplikatua I, Plá García, Jorge, Munguira Ruiz, Asier, Rafkin, Scot, Newman, Claire E., Bertrand, Tanguy, Martínez, Germán, Hueso Alonso, Ricardo, Sánchez Lavega, Agustín María, Del Río Gaztelurrutia, María Teresa, Stott, Alexander E., Murdoch, Naomi, de la Torre Juárez, Manuel, Lemmon, Mark T., Chide, Baptiste, Viúdez Moreiras, Daniel, Savijärvi, Hannu, Richardson, Mark I., Marín Jiménez, Mercedes, Sebastián, Eduardo, Lepinette, Alain, Mora Sotomayor, Luis, and Rodríguez Manfredi, José Antonio

Abstract

Mars 2020 Mars Environmental Dynamics Analyzer (MEDA) instrument data acquired during half of a Martian year (Ls 13°–180°), and modeling efforts with the Mars Regional Atmospheric Modeling System (MRAMS) and the Mars Climate Database (MCD) enable the study of the seasonal evolution and variability of nocturnal atmospheric turbulence at Jezero crater. Nighttime conditions in Mars's Planetary Boundary Layer are highly stable because of strong radiative cooling that efficiently inhibits convection. However, MEDA nighttime observations of simultaneous rapid fluctuations in horizontal wind speed and air temperatures suggest the development of nighttime turbulence in Jezero crater. Mesoscale modeling with MRAMS also shows a similar pattern and enables us to investigate the origins of this turbulence and the mechanisms at play. As opposed to Gale crater, less evidence of turbulence from breaking mountain wave activity was found in Jezero during the period studied with MRAMS. On the contrary, the model suggests that nighttime turbulence at Jezero crater is explained by increasingly strong wind shear produced by the development of an atmospheric bore-like disturbance at the nocturnal inversion interface. These atmospheric bores are produced by downslope winds from the west rim undercutting a strong low-level jet aloft from ∼19:00 to 01:00 LTST and from ∼01:00 LTST to dawn when undercutting weak winds aloft. The enhanced wind shear leads to a reduction in the Richardson number and an onset of mechanical turbulence. Once the critical Richardson Number is reached (Ri ∼ <0.25), shear instabilities can mix warmer air aloft down to the surface.

Published
2023

39. Wind and turbulence observations with the Mars microphone on Perseverance

Author

Stott, Alexander E., primary, Murdoch, Naomi, additional, Gillier, Martin, additional, Banfield, Don, additional, Bertrand, Tanguy, additional, Chide, Baptiste, additional, De la Torre Juarez, Manuel, additional, Hueso, Ricardo, additional, Lorenz, Ralph, additional, Martinez, German, additional, Munguira, Asier, additional, Sotomayor, Luis Mora, additional, Navarro, Sara, additional, Newman, Claire, additional, Pilleri, Paolo, additional, Pla‐Garcia, Jorge, additional, Rodriguez‐Manfredi, Jose Antonio, additional, Sanchez‐Lavega, Agustin, additional, Smith, Michael, additional, Moreiras, Daniel Viudez, additional, Williams, Nathan, additional, Maurice, Sylvestre, additional, Wiens, Roger C., additional, and Mimoun, David, additional

Published
2023
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40. Population pharmacokinetics and CSF penetration of flucytosine in adults with HIV-associated cryptococcal meningoencephalitis

Author

Stott, Katharine E, primary, Ahmadu, Ajisa, additional, Kajanga, Cheusisime, additional, Moyo, Melanie, additional, Gondwe, Ebbie, additional, Chimang’anga, Wezzie, additional, Chasweka, Madalitso, additional, Unsworth, Jennifer, additional, Jimenez-Valverde, Ana, additional, Jagota, Bhavana, additional, Shah, Reya V, additional, Lawrence, David S, additional, Lalloo, David G, additional, Harrison, Tom, additional, Jarvis, Joseph N, additional, Hope, William, additional, and Mwandumba, Henry C, additional

Published
2023
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46. Overview of the ITER Diagnostic System

Author

Costley, A. E., Ebisawa, K., Edmonds, P., Janeschitz, G., Johnson, L. C., Kasai, S., de Kock, L., Mukhovatov, V., Stott, P. E., Vayakis, G., Walker, C., Yamamoto, S., Young, K. M., Zaveriaev, V., Stott, Peter E., editor, Gorini, Giuseppe, editor, Prandoni, Paolo, editor, and Sindoni, Elio, editor

Published
1998
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47. Role and Requirements for Plasma Measurements on ITER

Author

ITER Joint Central Team and Home Teams, Mukhovatov, V. S., Bartiromo, R., Boucher, D., Costley, A. E., de Kock, L., Ebisawa, K., Edmonds, P., Gribov, Yu., Janeschitz, G., Johnson, L. C., Kasai, S., Marmar, E., Nagashima, A., Petrov, M., Post, D. E., Stott, P. E., Strelkov, V. S., Vayakis, G., Walker, C. I., Wesley, J., Yamamoto, S., Young, K. M., Zaveriaev, V. S., Stott, Peter E., editor, Gorini, Giuseppe, editor, Prandoni, Paolo, editor, and Sindoni, Elio, editor

Published
1998
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48. SEIS: Insight’s Seismic Experiment for Internal Structure of Mars

Author

Lognonné, P., Banerdt, W. B., Giardini, D., Pike, W. T., Christensen, U., Laudet, P., de Raucourt, S., Zweifel, P., Calcutt, S., Bierwirth, M., Hurst, K. J., Ijpelaan, F., Umland, J. W., Llorca-Cejudo, R., Larson, S. A., Garcia, R. F., Kedar, S., Knapmeyer-Endrun, B., Mimoun, D., Mocquet, A., Panning, M. P., Weber, R. C., Sylvestre-Baron, A., Pont, G., Verdier, N., Kerjean, L., Facto, L. J., Gharakanian, V., Feldman, J. E., Hoffman, T. L., Klein, D. B., Klein, K., Onufer, N. P., Paredes-Garcia, J., Petkov, M. P., Willis, J. R., Smrekar, S. E., Drilleau, M., Gabsi, T., Nebut, T., Robert, O., Tillier, S., Moreau, C., Parise, M., Aveni, G., Ben Charef, S., Bennour, Y., Camus, T., Dandonneau, P. A., Desfoux, C., Lecomte, B., Pot, O., Revuz, P., Mance, D., tenPierick, J., Bowles, N. E., Charalambous, C., Delahunty, A. K., Hurley, J., Irshad, R., Liu, Huafeng, Mukherjee, A. G., Standley, I. M., Stott, A. E., Temple, J., Warren, T., Eberhardt, M., Kramer, A., Kühne, W., Miettinen, E.-P., Monecke, M., Aicardi, C., André, M., Baroukh, J., Borrien, A., Bouisset, A., Boutte, P., Brethomé, K., Brysbaert, C., Carlier, T., Deleuze, M., Desmarres, J. M., Dilhan, D., Doucet, C., Faye, D., Faye-Refalo, N., Gonzalez, R., Imbert, C., Larigauderie, C., Locatelli, E., Luno, L., Meyer, J.-R., Mialhe, F., Mouret, J. M., Nonon, M., Pahn, Y., Paillet, A., Pasquier, P., Perez, G., Perez, R., Perrin, L., Pouilloux, B., Rosak, A., Savin de Larclause, I., Sicre, J., Sodki, M., Toulemont, N., Vella, B., Yana, C., Alibay, F., Avalos, O. M., Balzer, M. A., Bhandari, P., Blanco, E., Bone, B. D., Bousman, J. C., Bruneau, P., Calef, F. J., Calvet, R. J., D’Agostino, S. A., de los Santos, G., Deen, R. G., Denise, R. W., Ervin, J., Ferraro, N. W., Gengl, H. E., Grinblat, F., Hernandez, D., Hetzel, M., Johnson, M. E., Khachikyan, L., Lin, J. Y., Madzunkov, S. M., Marshall, S. L., Mikellides, I. G., Miller, E. A., Raff, W., Singer, J. E., Sunday, C. M., Villalvazo, J. F., Wallace, M. C., Banfield, D., Rodriguez-Manfredi, J. A., Russell, C. T., Trebi-Ollennu, A., Maki, J. N., Beucler, E., Böse, M., Bonjour, C., Berenguer, J. L., Ceylan, S., Clinton, J., Conejero, V., Daubar, I., Dehant, V., Delage, P., Euchner, F., Estève, I., Fayon, L., Ferraioli, L., Johnson, C. L., Gagnepain-Beyneix, J., Golombek, M., Khan, A., Kawamura, T., Kenda, B., Labrot, P., Murdoch, N., Pardo, C., Perrin, C., Pou, L., Sauron, A., Savoie, D., Stähler, S., Stutzmann, E., Teanby, N. A., Tromp, J., van Driel, M., Wieczorek, M., Widmer-Schnidrig, R., and Wookey, J.

Published
2019
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50. Requirements for ITER Diagnostics

Author

Costley, A E, Bartiromo, R, deKock, L, Marmar, E, Matoba, T, Mukhovatov, V, Muraoka, K, Nagashima, A, Orlinski, D, Petrov, M, Stott, P E, Strelkov, V, Yamamoto, S, Young, K M, Stott, Peter E., editor, Gorini, Giuseppe, editor, and Sindoni, Elio, editor

Published
1996
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