560 results on '"Jones Thomas"'
Search Results
2. Nurses' experiences on using Open Dialogue Approach in a local mental health service : an interpretative phenomenological analysis
- Author
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Jones, Thomas Mark
- Subjects
362.2 - Abstract
Background: Open Dialogue Approach (ODA) is a collaborative intervention and framework for using with service users with complex mental health such as psychosis. Aims: To explore nurses’ experiences when using ODA and in particular how ODA culture compares to other mental health cultures within a local health board. Method: Through the qualitative approach of Interpretative Phenomenological Analysis five members of staff were purposively sampled and participated in the research. Findings: The participants discussed ideas and concepts that developed into the following themes: the first theme was based on learning ODA skills and concluded that experiential learning and more formalised teaching is beneficial for ODA roll out, however, having a more experienced clinician partnered with a novice is crucial. The second theme focussed on participants perception of impact: all participants/clinicians agreed that ODA was an effective approach for the service users they worked with, due to the therapeutic relationship, service user empowerment and openness and transparency. The third theme identified ‘barriers’: the ODA principle of tolerance of uncertainty was a barrier that was encountered by the participants. Participants felt they must take positive risks and use minimal recording and not communicate about the service user without their presence, which is not in keeping with current legislation (UK and Wales). Also of significance is the fact that the service user is empowered within ODA to lead and direct the conversation which could be perceived as a barrier by some staff and professional groups who may feel threatened by this. This was evident in managing staff emotions within initial network meetings, managing risk and maintaining professional boundaries. In order to overcome this, the principle of tolerance of uncertainty was relaxed by participants in order to manage risk and for them to comply with current legislation. The empowered relationship in ODA is critical (through clinicians being open and truthful), as it appears to be the central and core intervention mechanism within ODA. Conclusion: ODA is reported as being effective by the participants within this study, but it will require further research to demonstrate this effectiveness within the UK to the wider clinical body and policy developers. The study also indicates a mechanism for ODA effectiveness: control and empowerment of the service user and openness/transparentness from clinicians. If this is employed then it appears that the principle of tolerance of uncertainty can be ameliorated to fit with UK legislation.
- Published
- 2019
3. Fissures and fountains : magma dynamics in basaltic conduits
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Jones, Thomas James
- Subjects
550 - Abstract
Basaltic volcanoes are responsible for the bulk of the planet’s magma output. Their eruptions are often spectacular and can have serious impacts on a local scale (through lava flows) and regional scale (through emission of ash and toxic gases). However, hazard planning and mitigation is challenging because these eruptions can be highly variable both temporally, lasting from hours to months, and spatially, localizing from a long, linear fissure to a discrete vent. In this thesis, I will explore the role that magma transport and eruption dynamics play in controlling the evolution of basaltic fissure eruptions in time and space. Firstly, I present results from a detailed field investigation of the proximal deposits from episode 1 of the 1969 fissure eruption of Mauna Ulu, Kīlauea, Hawai‘i. Exceptional preservation of the deposits allows for the reconstruction of vent-proximal lava drainage patterns and the assessment of the role that drainage played in controlling vent localization. Secondly, I provide the first in-depth textural classification of low Hawaiian fountaining (< 100 m) products. Using spatter from the Mauna Ulu fissure eruption, I describe how the magma matured and produced late-stage spatter during the waning stages of the eruption. Furthermore, a new type of spatter is identified and interpreted to form by the disruption of lava flows above tectonic ground cracks; presenting a potential for misinterpretation of eruptive vents. Thirdly, through a series of scaled analogue experiments, I explore how the simultaneous drainage of dense, degassed, viscous magma and upwelling of less dense, less viscous magma can influence flow processes in the volcanic conduit. This convective system is characterized via the dimensionless Grashof number (Gr), which is a ratio of viscous to buoyancy forces. At low Gr (≲ 0.1), efficient laminar flow is observed with narrow, well-defined fingers of upwelling fluid separated by broad regions of downwelling fluid. As Gr increases (to ~ 100), the flow becomes increasingly chaotic and exchange becomes inefficient – no stable fingers or regions of coherent flow are established. Furthermore, the intrinsic properties of the fissure system (Gr) are related to the extrinsic properties (Reynolds number, Re – a ratio of inertial to viscous forces) to give the empirical relationship: Re = 0.0401Gr^(0.767). Together, these field and lab data suggest that “top-down” lava drainage processes and “bottom-up” convective processes in basaltic fissure eruptions conspire together to control their localization and longevity. This new knowledge advances our understanding of how magma dynamics can influence key, hazard-relevant eruption parameters, such as: mass eruption rate, dynamics of proximal lava flow emplacement, lava fountain vigour, and eruption evolution. This work highlights the importance of understanding the central role that magma dynamics have in shaping volcanic eruptions in order to develop more robust conceptual and physical models of eruptive behaviour.
- Published
- 2018
4. Enhanced electrodeposition for the filling of micro-vias
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Jones, Thomas David Arthur, Desmulliez, Marc, and Flynn, David
- Subjects
621.3815 - Abstract
This thesis investigated the introduction of megasound (MS) (1MHz) acoustic technology as an enhanced agitation method of an electrolyte solution for the electrochemical deposition of copper (Cu), used in electroplating processes. The thesis, carried out at Merlin Circuit Technology Ltd, studied the possibility of improving processing capabilities for use in Printed Circuit Board (PCB) industrial manufacture. Prior laboratory experiments demonstrated increased metallisation of vertical interconnect access (via) features in a Printed Circuit Board (PCB), which, if applied within manufacturing, would enable increased connectivity throughout a PCB and result in cost savings. PCB manufacturing quality after MS-assisted Cu electroplating was assessed by measurements of the topography of the electrodeposits, using scanning electron microscopy and white-light interferometry. Cu plating rate changes were also measured on the surface of the PCB and inside the vias. After plating Cu with MS-assistance, the macro and microscale surface composition was demonstrated to alter due to the direct influence of the acoustic waves. Systematic characteristic of the surface was conducted by varying the settings of the acoustic transducer device as well as the process parameters including electrical current distribution, bath additive chemistry and solution temperature. MS processing was shown to produce unique Cu artefacts. Their deleterious formation was demonstrated to be influenced by acoustic standing waves and microbubble formations at the electrolyte solution/PCB interface. Causes of these artefacts, microfluidic streaming and cavitation, were also observed and controlled to reduce the creation of these artefacts. MS plating Cu down through-hole via (THV) and blind-via (BV) interconnects was shown to produce measureable benefits. These include, for THVs, a 700 % increase of Cu plating deposit thickness within a 175 μm diameter, depth-to-width aspect ratio (ar) of 5.7:1, compared with processing under no-agitation conditions. For BVs, a 60 % average increase in Cu deposition in 150 μm and 200 μm, ar 1:1, was demonstrated against plating under standard manufacturing conditions - bubble agitation and panel movement.
- Published
- 2017
5. Rethinking natural hazards research and engagement to include co-creation with Indigenous communities
- Author
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Jones, Thomas J., Nyce, Harry, Moigne, Yannick Le, Williams-Jones, Glyn, Nyce, Deanna, Jones, Thomas J., Nyce, Harry, Moigne, Yannick Le, Williams-Jones, Glyn, and Nyce, Deanna
- Abstract
Indigenous peoples are widely affected by natural hazards and their history and knowledge can directly inform on past events and mitigation strategies. Here we show how effective co-creation of resources and bi-lateral knowledge exchange between natural hazard researchers and local Indigenous communities provides an effective, equitable, and sustainable way to conduct research.
- Published
- 2024
6. Spread or Splash : The Ubiquitous Role of Droplets in Mafic Explosive Eruptions
- Author
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Comida, Pier Paolo, Jones, Thomas J., Comida, Pier Paolo, and Jones, Thomas J.
- Abstract
Magma fragmentation is an essential process driving explosive volcanic eruptions, generating a distribution of pyroclasts with characteristic shape and grain size. These characteristics are often used to inform on the energetics of magma fragmentation and the associated eruption style and intensity. However, a portion of these pyroclasts, droplets when still in the molten state, are likely to be generated through impact mechanisms (i.e., collisions), and subsequent secondary fragmentation (i.e., splashing). Here, we successfully apply and dynamically scale concepts and findings of liquid droplet impacts in engineering to magma fragmentation processes in volcanology. We compile and model physical data for two mafic melt compositions (kimberlite and basalt) and use specific eruption examples from Igwisi Hills, Kīlauea and Stromboli volcanoes to define composition‐specific impact dynamics. Pyroclast impact dynamics have a direct control on in‐conduit processes, eruption dynamics, and ash dispersal. For low viscosity mafic melts such as kimberlite and basalt, pyroclast impacts can lead to both splash and deposition on the conduit wall, resulting either in conduit clearing or conduit narrowing, respectively. In both cases, shifting the impact regime toward surface deposition will lead to an inexorable decay in explosiveness, potentially switching the eruption style to effusive behavior. This has direct consequences for the transport of volcanic ash at the surface and inferring magma fragmentation processes (e.g., energies) from the depositional record.
- Published
- 2024
7. Mildly explosive eruptions at Martian low-shield volcanoes
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Pieterek, Bartosz, Jones, Thomas J., Pieterek, Bartosz, and Jones, Thomas J.
- Abstract
Ongoing acquisition of Martian surface imagery constantly provides new opportunities to reveal previously undiscovered small-scale volcanic landforms, yielding critical insights into volcanic processes, and challenging existing inferences. Here, using the most recent, high-resolution topographical data, we mapped the accumulation of pyroclastic deposits occurring along the margins of several volcanic vents. They share morphological similarities with terrestrial volcanic deposits attributed to low-intensity lava fountaining occurring during mild explosive activity. Our identified, explosive volcanic deposits are associated with late Amazonian volcanic activity in Tharsis. The identification of these very recent (
- Published
- 2024
8. Permeability of granular mixtures under shear
- Author
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Lipiejko, Natalia, Jones, Thomas, Lipiejko, Natalia, and Jones, Thomas
- Abstract
Fluidised granular flows are gas–particle mixtures that occur in a wide range of industrial applications and geophysical flows. One factor governing the fluidisation behaviour of a granular flow is its permeability — the ability of the gas to move through the particle column. Although extensive research has been carried out on the gas–particle permeability under static conditions, most of the industrial and geophysical processes are dynamic phenomena, where parameters such as the shear rate change with both time and space. Here, the effects of shear rate on the permeability of gas–particle mixtures were studied through novel experiments where a granular column comprising particles of diameter 63–250 Um was sheared at shear rates between 0 and 213 s−1 while an increasing flux of compressed air was introduced into the base of the column. Regardless of the shear rate, the granular column starts to expand upon increasing the air velocity, however, columns sheared at higher rates require greater air velocities to exhibit bubbling (and column expansion). We also instrumented the column with a pressure sensor. For the static column, as the air velocity increases, the pressure gradient across the granular column increases linearly until it reaches a maximum value, slightly decreases, and then plateaus. Conversely, for high shear rates, the pressure gradient continuously increases with increased air velocity, never reaching a maximum value or a plateau. The pressure gradient data were analysed alongside the videography in terms of the minimum fluidisation velocity and the minimum bubbling velocity, and both were found to be greater for higher shear rates. Consequently, our results show that increased shear increases the permeability of granular columns and the experimental data further suggests that in order to accurately describe the evolution of the pressure gradient across a sheared granular column, processes in the vertical as well as radial plane should be taken into ac
- Published
- 2024
9. Percutaneous Balloon-Expandable Stent Implantation to Treat Transverse Aortic Arch Obstruction: Medium- to Long-Term Outcomes of a Retrospective Multicenter Study
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Cardiologie, Cluster A, Circulatory Health, Team Medisch, Salavitabar, Arash, Eisner, Mariah, Armstrong, Aimee K, Boe, Brian A, Chisolm, Joanne L, Cheatham, John P, Cheatham, Sharon L, Forbes, Thomas, Jones, Thomas K, Krings, Gregor J, Morray, Brian H, Steinberg, Zachary L, Akam-Venkata, Jyothsna, Voskuil, Michiel, Berman, Darren P, Cardiologie, Cluster A, Circulatory Health, Team Medisch, Salavitabar, Arash, Eisner, Mariah, Armstrong, Aimee K, Boe, Brian A, Chisolm, Joanne L, Cheatham, John P, Cheatham, Sharon L, Forbes, Thomas, Jones, Thomas K, Krings, Gregor J, Morray, Brian H, Steinberg, Zachary L, Akam-Venkata, Jyothsna, Voskuil, Michiel, and Berman, Darren P
- Published
- 2024
10. Water-soluble rare earth elements (REEs) recovered from uranium tailings
- Author
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Levett, Alan, van der Ent, Antony, Ray Jones, Thomas, Bolouri, Kimiya, Kelly, Kieran, Vaughan, James, Edraki, Mansour, Erskine, Peter, Southam, Gordon, Levett, Alan, van der Ent, Antony, Ray Jones, Thomas, Bolouri, Kimiya, Kelly, Kieran, Vaughan, James, Edraki, Mansour, Erskine, Peter, and Southam, Gordon
- Abstract
The global energy transition from fossil fuels to renewable sources poses substantial challenges to increase metal production, including industry-critical rare earth elements (REEs). Environmental and social concerns obfuscate the production of these ‘green’ metals and only ∼1% of REE demand is met from recycling. This work highlights the potential for the ‘economic rehabilitation’ of the Mary Kathleen Mine, a relinquished uranium (U) mine with very high (∼3 wt%) total REE concentrations within the tailings storage facility (TSF). Leaching of the tailings revealed that approximately 5% of the REEs are water-soluble, suggesting the possibility for in situ extraction. Using an in situ water leach, the projected total REE recovery is >10,000 t, which would exceed the total amount of U recovered (7,532 t) during the initial mining operation. The proposed in situ recovery would offer a truck-free mine, using solar energy and water recycling technologies to recover REEs from a waste source, reducing environmental contamination.
- Published
- 2024
11. Understanding spectral artefacts in SKA-LOW 21-cm cosmology experiments: the impact of cable reflections
- Author
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O'Hara, Oscar Sage David, Dulwich, Fred, Acedo, Eloy de Lera, Dhandha, Jiten, Gessey-Jones, Thomas, Anstey, Dominic, Fialkov, Anastasia, O'Hara, Oscar Sage David, Dulwich, Fred, Acedo, Eloy de Lera, Dhandha, Jiten, Gessey-Jones, Thomas, Anstey, Dominic, and Fialkov, Anastasia
- Abstract
The Cosmic Dawn marks the first star formations and preceded the Epoch-of-Reionization, when the Universe underwent a fundamental transformation propelled by the radiation from these first stars and galaxies. Interferometric 21-cm experiments aim to probe redshifted neutral hydrogen signals from these periods, constraining the conditions of the early Universe. The SKA-LOW instrument of the Square Kilometre Array telescope is envisaged to be the largest and most sensitive radio telescope at m and cm wavelengths. The latest Aperture Array Verification Systems feature 7m coaxial transmission lines connecting the Low Noise Amplifiers to optical transmitters at the front of the analogue-receiving chain. An impedance mismatch between these components results in a partially reflected electromagnetic signal, which introduces chromatic aberrations in the instrument bandpass. This causes power from the foreground signals to appear at higher delays, potentially contaminating the EoR window, a region at which the 21-cm signal should be detectable. We present an end-to-end simulation pipeline for SKA-LOW using a composite sky model combining radio foregrounds from The GLEAM Survey, Haslam $408$MHz, and a $1.5$cGpc 21-cm brightness temperature cube generated with the 21cmSPACE simulator. Iterating a parametric approach, we derive a model for the scattering parameters of a coaxial transmission line in terms of its specifications and bulk material properties. Assuming identical cables of length $\leq 15.0$m with impedance mismatch $\leq 10\Omega$ confines the reflection to k-modes below the EoR window. However, we demonstrate that even a $0.1$% length tolerance introduces contamination with an RMSE of $\sim 10$% across all accessible k-modes., Comment: 16 pages, 11 figures
- Published
- 2024
12. Identifying rheological regimes within pyroclastic density currents
- Author
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Jones, Thomas. J., Shetty, Abhishek, Chalk, Caitlin, Dufek, Josef, Gonnermann, Helge M., Jones, Thomas. J., Shetty, Abhishek, Chalk, Caitlin, Dufek, Josef, and Gonnermann, Helge M.
- Abstract
Pyroclastic density currents (PDCs) are the most lethal of all volcanic hazards. An ongoing challenge is to accurately forecast their run-out distance such that effective mitigation strategies can be implemented. Central to this goal is an understanding of the flow mobility—a quantitative rheological model detailing how the high temperature gas-pyroclast mixtures propagate. This is currently unknown, yet critical to accurately forecast the run-out distance. Here, we use a laboratory apparatus to perform rheological measurements on real gas-pyroclast mixtures at dynamic conditions found in concentrated to intermediate pumice-rich PDCs. We find their rheology to be non-Newtonian featuring (i) a yield stress where deposition occurs; (ii) shear-thinning behavior that promotes channel formation and local increases in velocity and (iii) shear-thickening behavior that promotes decoupling and potential co-PDC plume formation. We provide a universal regime diagram delineating these behaviors and illustrating how flow can transition between them during transport.
- Published
- 2024
13. Advancing the Development of the Magneto-Active Slosh Control (MaSC) System for Spacecraft and Launch Vehicles
- Author
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antalece, Antalec, Eden, Kolipaka, Karthik, Murray, Jack, Belekewicz, Cora, Metz, Dara, Damon, Anthony, Wlodarski, Michal, Rocha-Puscar, Jose, Jones, Thomas, antalece, Antalec, Eden, Kolipaka, Karthik, Murray, Jack, Belekewicz, Cora, Metz, Dara, Damon, Anthony, Wlodarski, Michal, Rocha-Puscar, Jose, and Jones, Thomas
- Abstract
The Magneto-Active Propellant Management Device (MAPMD) system is designed to address safety hazards in liquid-propellant spaceflight caused by sloshing. This innovative system of Magneto-Active Slosh Control surpasses traditional passive slosh baffles by reducing mass, improving surface wave suppression, and minimizing volumetric intrusion (Santhanam 2012). In prior fight experiments conducted in collaboration between Embry-Riddle Aeronautical University and Carthage College, remnant slosh suppression was observed, however the effective slosh damping did not meet our expectations due to inadequate control forces. We are redesigning the magnetic membrane with multiple layers of ultrahigh-permeability metallic glass film and are developing an optimized configuration of current-carrying coils to increase magnetic force and field performance. These advancements are expected to elevate the MAPMD system's Technology Readiness Level (TRL) from 3 to 4 in order to pave the way for microgravity flight testing. The MAPMD system promises to enhance the safety and performance of liquid-propellant spaceflight by actively managing slosh dynamics.
- Published
- 2024
14. Integrating above and belowground components of biodiversity across spatial scales : the role of host plants in the distribution of Arbuscular Mycorrhizal fungi
- Author
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Jones, Thomas Michael
- Subjects
579.5 ,QK Botany ,QR Microbiology - Abstract
The Arbuscular Mycorrhizal (AM) fungi are a group of obligate plant root endosymbionts, which form associations with an estimated two thirds of terrestrial plant species. Their extra-radical mycelium extends throughout the soil and absorbs nutrients that are transferred to their host plant in exchange for a purely phytogenic carbon supply. Due to their ubiquity and their functional importance, they are the subject of much research into their community ecology, yet much is still unknown. For instance: whether or not AM fungi display preference for certain host plant species; how environmental heterogeneity and energy availability affect communities; and the relative influence of niche and neutral processes. This thesis describes experiments which profile AM fungal communities and environmental properties of their habitat at different spatial scales in different plant species. Network analysis revealed patterns indicative of niche-based processes structuring AM fungal communities more than neutral processes, phenotypic trade-offs between AM fungi, and of priority effects influencing diversity and unevenness. Difference between plant species in the heterogeneity of surrounding soil was dependent on spatial scale. The effect of decreased carbon allocation on AM fungal communities is greater in more heterogeneous habitats. These results suggest that the detection of host plant preference in AM fungi is dependent on spatial scale of sampling, driven by interspecific variation in plant root architecture, soil physical properties and AM fungal vital rates.
- Published
- 2015
15. Concurrent training : neuroendocrine and molecular mechanisms of strength and endurance training incompatibility
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Jones, Thomas, French, Duncan, Howatson, Glyn, and Russell, Mark
- Subjects
613.7 ,C600 Sports Science - Abstract
Combining strength and endurance training within the same regimen is aptly referred to as “concurrent training”. Research conducted over the previous 3 decades has indicated concurrent training can result in attenuated development of strength, power and hypertrophy when compared to strength training in isolation. Despite extensive research the mechanisms contributing to this so called “interference effect” are yet to be fully elucidated, as is the influence of manipulating acute training programme variables within a concurrent regimen. As such, the purposes of this thesis were to investigate and draw conclusions regarding underlying physiological mechanisms relating to the interference effect. Additionally, this thesis sought to examine the effects of manipulating programme variables, including frequency and sequencing of exercise within concurrent training regimens on strength related adaptation. The findings of this thesis indicate overall training volume and frequency of endurance training within a concurrent intervention influences the presence and magnitude of the inhibition of strength development. Concurrent training volumes of 3 d·wk-1 elicited muted strength development, whereas lower frequencies did not. Whilst interference was not attributable to neuromuscular factors, it was reported that cortisol was only elevated following higher training frequencies, indicating training stress and catabolism may contribute to interference. Additionally, the sequencing of strength and endurance training can influence endocrine and signalling responses associated with strength adaptation, and it appears strength prior to endurance elicits greater increases in growth associated signalling. The findings of this thesis indicate that overall training stress influences the presence and magnitude of interference experienced, and is reflected in catabolic endocrine responses. Additionally, strength prior to endurance training promotes more favourable anabolic signalling than vice versa, which over time may contribute to greater strength type adaptations.
- Published
- 2014
16. French republican exiles in Britain, 1848-1870
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Jones, Thomas Chewning
- Subjects
900 ,Political refugees--France--History--19th century ,Political refugees--Great Britain--History--19th century ,France--Politics and government--1848-1870 ,Great Britain--History--19th century - Published
- 2010
17. The response of low-latitude calcareous phytoplankton to global change through the Eocene-Oligocene transition
- Author
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Jones, Thomas Dunkley
- Subjects
560 - Abstract
This thesis documents the response of calcareous phytoplankton assemblages to major changes in global climate during the Eocene-Oligocene transition (EOT) at three low-latitude sites Tanzanian Drilling Project (TDP) Sites 12 & 17 (southern coastal Tanzania), Deep Sea Drilling Site 242 (Mozambique Channel, western Indian Ocean) and St Stephens Quarry (Alabama, USA). High-resolution nannofossil count data from all three study sites clearly indicate a major change in coccolithophore assemblage compositions directly coincident with the first step change in the positive oxygen isotope (d180) shift into the early Oligocene Glacial Maximum (EOGM). This is followed by continued shifts in coccolithophore assemblages in the vicinity of the Eocene-Oligocene boundary to reach new "Oligocene" assemblage compositions before the second step in duO and peak glacial conditions of the EOGM. At all sites there is a marked increase in the abundance of Cyclicargolithus floridanus (>5um) and to a lesser extent Sphenolithus predistentus, combined with a general loss of warm-water and oligotrophic taxa including Calcidiscus protoannulus, discoaster and holococcolith species. This consistent pattern of biotic change, from sites with varying species compositions and preservation states, indicates a large and geographically widespread perturbation in the low-latitude surface water environment and is consistent with new trace metal paleothermometry that indicates a significant, 2-3 C, cooling of surface waters in the earliest stages of the EOT. An exceptionally-well preserved and highly diverse nannofossil assemblage from late Eocene-early Oligocene (nannofossil zones NP19/20 to NP21 Martini 1971) sediments of coastal Tanzania is described and its implications for the Cenozoic history of the coccolithophores is discussed. This consists of a total of 114 species-equivalent morphotypes, one new genus (Pocillithus), six new species (Reticulofenestra macmillanii, Blackites culter, Rhabdosphaera suptilis, Orthozygus occultus, Orthozygus arms, Pocillithus spinulifer) and a previously unknown Paleogene deep-photic zone assemblage including representatives of the extant genera Gladiolithus, Algirosphaera and Acanthoica.
- Published
- 2008
18. Natural enemies in aphid communities
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Jones, Thomas
- Subjects
595.717 - Published
- 2007
19. Deposition and the absolute king : the 'Confessio Amantis' and Gower's philosophy of kingship
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Hodgson-Jones, Thomas Jeffrey
- Subjects
821.1 - Published
- 2006
20. Accounting and technology transfer : a sociological study
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Jones, Thomas Colwyn
- Subjects
658 ,Advanced manufacturing technology - Published
- 1995
21. The phenomenology of love
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Jones, Thomas Paul
- Subjects
100 ,Philosophy - Published
- 1995
22. Transport and eruption of mantle xenoliths creates a lagging problem
- Author
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Russell, James K., Jones, Thomas J., Russell, James K., and Jones, Thomas J.
- Abstract
Mantle-derived xenoliths entrained by low viscosity magmas indicate transport through great thicknesses of orogenic (≲50-80 km) and cratonic (≲20 km) mantle lithosphere. The size and density of xenoliths dictate that, relative to the ascending magma, they continuously settle during transport. This creates a lag time between when the initial sampling magma reaches the Earth’s surface and the arrival of the xenoliths. The magnitude of this lag time depends on xenolith properties, sampling depth and the magma ascent velocity. Here, using settling calculations, we develop this lag time concept and show how eruption durations and volumes can impact the distribution, abundance, and properties (e.g., sample depths, size) of xenoliths. Lag times can account for heterogenous xenolith distributions within volcanic deposits, the potential biased sampling of the mantle lithosphere, and can constrain minimum eruption volumes required to transport and erupt the deepest sourced xenoliths such as those producing diamondiferous kimberlites.
- Published
- 2023
23. Physiological responses and performance factors for double-poling and diagonal-stride treadmill roller-skiing time-trial exercise
- Author
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Andersson, Erik P., Lögdal, Nestor, Byrne, Darragh, Jones, Thomas W., Andersson, Erik P., Lögdal, Nestor, Byrne, Darragh, and Jones, Thomas W.
- Abstract
Purpose To compare physiological responses between a self-paced 4-min double-poling (DP) time-trial (TTDP) versus a 4-min diagonal-stride (DS) time-trial (TTDS). The relative importance of peak oxygen uptake (V˙V˙O2peak), anaerobic capacity, and gross efficiency (GE) for projection of 4-min TTDP and TTDS roller-skiing performances were also examined. Methods Sixteen highly trained male cross-country skiers performed, in each sub-technique on separate occasions, an 8 × 4-min incremental submaximal protocol, to assess individual metabolic rate (MR) versus power output (PO) relationships, followed by a 10-min passive break and then the TTDP or TTDS, with a randomized order between sub-techniques. Results In comparison to TTDS, the TTDP resulted in 10 ± 7% lower total MR, 5 ± 4% lower aerobic MR, 30 ± 37% lower anaerobic MR, and 4.7 ± 1.2 percentage points lower GE, which resulted in a 32 ± 4% lower PO (all P < 0.01). The V˙V˙O2peak and anaerobic capacity were 4 ± 4% and 30 ± 37% lower, respectively, in DP than DS (both P < 0.01). The PO for the two time-trial (TT) performances were not significantly correlated (R2 = 0.044). Similar parabolic pacing strategies were used during both TTs. Multivariate data analysis projected TT performance using V˙V˙O2peak, anaerobic capacity, and GE (TTDP, R2 = 0.974; TTDS, R2 = 0.848). The variable influence on projection values for V˙V˙O2peak, anaerobic capacity, and GE were for TTDP, 1.12 ± 0.60, 1.01 ± 0.72, and 0.83 ± 0.38, respectively, and TTDS, 1.22 ± 0.35, 0.93 ± 0.44, and 0.75 ± 0.19, respectively. Conclusions The results show that a cross-country skier’s “metabolic profile” and performance capability are highly sub-technique specific and that 4-min TT performance is differentiated by physiological factors, such as V˙V˙O2peak, anaerobic capacity, and GE.
- Published
- 2023
- Full Text
- View/download PDF
24. Influenza Adverse Events in Patients with Rheumatoid Arthritis, Ulcerative Colitis, or Psoriatic Arthritis in the Tofacitinib Clinical Development Programs
- Author
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Winthrop, Kevin L., Yndestad, Arne, Henrohn, Dan, Danese, Silvio, Marsal, Sara, Galindo, Maria, Woolcott, John C., Jo, Hyejin, Kwok, Kenneth, Shapiro, Andrea B., Jones, Thomas V., Diehl, Annette, Su, Chinyu, Panes, Julian, Cohen, Stanley B., Winthrop, Kevin L., Yndestad, Arne, Henrohn, Dan, Danese, Silvio, Marsal, Sara, Galindo, Maria, Woolcott, John C., Jo, Hyejin, Kwok, Kenneth, Shapiro, Andrea B., Jones, Thomas V., Diehl, Annette, Su, Chinyu, Panes, Julian, and Cohen, Stanley B.
- Abstract
Introduction: This post hoc analysis evaluated influenza adverse events (AEs) across rheumatoid arthritis (RA), ulcerative colitis (UC), and psoriatic arthritis (PsA) tofacitinib clinical programs. Methods: Available data from phase 1, randomized phase 2/3/3b/4 clinical trials (completed by 2018), and long-term extension (LTE) studies (up to May 2019) in patients with RA, UC, and PsA were included [randomized or Overall (phase 1-3b/4 and LTE studies) tofacitinib cohorts]. Incidence rates (IRs; events per 100 patient-years) of combined influenza AEs (seasons 2004/2005 to 2018/2019) were analyzed, including by tofacitinib dose [5 or 10 mg twice daily (BID)] and age (< 65 versus >= 65 years). Logistic regression models evaluated risk factors for influenza AEs in the RA Overall tofacitinib cohort. Results: In randomized cohorts, combined influenza AE IRs were generally similar across tofacitinib, adalimumab, methotrexate, and placebo groups, across indications. Among Overall tofacitinib cohorts, combined influenza AE IRs with tofacitinib 5/10 mg BID, respectively, were higher in the UC (3.66/5.09) versus RA (2.38/2.19) and PsA (1.74/1.29) cohorts. IRs were generally similar across tofacitinib dose and age groups. Most influenza AEs were nonserious and did not require changes to tofacitinib treatment. Significant risk factors for influenza AEs in patients with RA were geographic region, baseline oral corticosteroid and methotrexate use, and tofacitinib dose. Conclusions: In the RA, UC, and PsA clinical programs, combined influenza AE IRs were highest in UC, while in each indication they were generally similar across tofacitinib, placebo, and comparator groups. Influenza AEs were predominantly nonserious and not associated with changes to tofacitinib treatment.
- Published
- 2023
- Full Text
- View/download PDF
25. Physical properties of pyroclastic density currents : relevance, challenges and future directions
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Jones, Thomas J., Beckett, Frances, Bernard, Benjamin, Breard, Eric C. P., Dioguardi, Fabio, Dufek, Josef, Engwell, Samantha, Eychenne, Julia, Jones, Thomas J., Beckett, Frances, Bernard, Benjamin, Breard, Eric C. P., Dioguardi, Fabio, Dufek, Josef, Engwell, Samantha, and Eychenne, Julia
- Abstract
Pyroclastic density currents (PDCs) are hazardous and destructive phenomena that pose a significant threat to communities living in the proximity of active volcanoes. PDCs are ground-hugging density currents comprised of high temperature mixtures of pyroclasts, lithics, and gas that can propagate kilometres away from their source. The physical properties of the solid particles, such as their grain size distribution, morphology, density, and componentry play a crucial role in determining the dynamics and impact of these flows. The modification of these properties during transport also records the causative physical processes such as deposition and particle fragmentation. Understanding these processes from the study of deposits from PDCs and related co-PDC plumes is essential for developing effective hazard assessment and risk management strategies. In this article, we describe the importance and relevance of the physical properties of PDC deposits and provide a perspective on the challenges associated with their measurement and characterization. We also discuss emerging topics and future research directions such as electrical charging, granular rheology, ultra-fine ash and thermal and surface properties that are underpinned by the characterization of pyroclasts and their interactions at the micro-scale. We highlight the need to systematically integrate experiments, field observations, and laboratory measurements into numerical modelling approaches for improving our understanding of PDCs. Additionally, we outline a need for the development of standardised protocols and methodologies for the measurement and reporting of physical properties of PDC deposits. This will ensure comparability, reproducibility of results from field studies and also ensure the data are sufficient to benchmark future numerical models of PDCs. This will support more accurate simulations that guide hazard and risk assessments.
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- 2023
26. Inverse Compton cooling of thermal plasma in colliding-wind binaries
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Mackey, Jonathan, Jones, Thomas A. K., Brose, Robert, Grassitelli, Luca, Reville, Brian, Mathew, Arun, Mackey, Jonathan, Jones, Thomas A. K., Brose, Robert, Grassitelli, Luca, Reville, Brian, and Mathew, Arun
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The inverse-Compton effect (IC) is a widely recognized cooling mechanism for both relativistic and thermal electrons in various astrophysical environments, including the intergalactic medium and X-ray emitting plasmas. Its effect on thermal electrons is however frequently overlooked in theoretical and numerical models of colliding-wind binaries (CWB). In this article, we provide a comprehensive investigation of the impact of IC cooling in CWBs, presenting general results for when the photon fields of the stars dominate the cooling of the thermal plasma and when shocks at the stagnation point are expected to be radiative. Our analysis shows that IC cooling is the primary cooling process for the shocked-wind layer over a significant portion of the relevant parameter space, particularly in eccentric systems with large wind-momentum ratios, e.g., those containing a Wolf-Rayet and O-type star. Using the binary system WR 140 as a case study, we demonstrate that IC cooling leads to a strongly radiative shocked wind near periastron, which may otherwise remain adiabatic if only collisional cooling was considered. Our results are further supported by 2D and 3D simulations of wind-wind collisions. Specifically, 3D magnetohydrodynamic simulations of WR 140 show a significant decrease in hard-X-ray emission around periastron, in agreement with observations but in contrast to equivalent simulations that omit IC cooling. A novel method is proposed for constraining mass-loss rates of both stars in eccentric binaries where the wind-collision zone switches from adiabatic to radiative approaching periastron. IC scattering is an important cooling process in the thermal plasma of CWBs., Comment: Accepted to MNRAS, 17 pages, 13 figures
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- 2023
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27. Using Multivariate Data Analysis to Project Performance in Biathletes and Cross-Country Skiers
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Jones, Thomas W., Lindblom, Hampus P., Laaksonen, Marko, McGawley, Kerry, Jones, Thomas W., Lindblom, Hampus P., Laaksonen, Marko, and McGawley, Kerry
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Purpose: To determine whether competitive performance, as defined by International Biathlon Union (IBU) and International Ski Federation (FIS) points in biathlon and cross-country (XC) skiing, respectively, can be projected using a combination of anthropometric and physiological metrics. Shooting accuracy was also included in the biathlon models. Methods: Data were analyzed using multivariate methods from 45 (23 female and 22 male) biathletes and 202 (86 female and 116 male) XC skiers who were all members of senior national teams, national development teams, or ski-university or high school invite-only programs (age range: 16-36 y). Anthropometric and physiological characteristics were assessed via dual-energy X-ray absorptiometry and incremental roller-ski treadmill tests, respectively. Shooting accuracy was assessed via an outdoor standardized testing protocol. Results: Valid projective models were identified for female biathletes' IBU points (R2 = .80/ Q2 = .65) and female XC skiers' FIS distance (R2 = .81/Q2 = .74) and sprint (R2 = .81/Q2 = .70) points. No valid models were identified for the men. The most important variables for the projection of IBU points were shooting accuracy, speeds at blood lactate concentrations of 4 and 2 mmol center dot L-1, peak aerobic power, and lean mass. The most important variables for the projection of FIS distance and sprint points were speeds at blood lactate concentrations of 4 and 2 mmol center dot L-1 and peak aerobic power. Conclusions: This study highlights the relative importance of specific anthropometric, physiological, and shooting-accuracy metrics in female biathletes and XC skiers. The data can help to identify the specific metrics that should be targeted when monitoring athletes' progression and designing training plans.
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- 2023
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28. A Computer Model of Simple Forms of Learning
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Jones, Thomas L. and Jones, Thomas L.
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- 2023
29. Piecewise Normalizing Flows
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Bevins, Harry, Handley, Will, Gessey-Jones, Thomas, Bevins, Harry, Handley, Will, and Gessey-Jones, Thomas
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Normalizing flows are an established approach for modelling complex probability densities through invertible transformations from a base distribution. However, the accuracy with which the target distribution can be captured by the normalizing flow is strongly influenced by the topology of the base distribution. A mismatch between the topology of the target and the base can result in a poor performance, as is typically the case for multi-modal problems. A number of different works have attempted to modify the topology of the base distribution to better match the target, either through the use of Gaussian Mixture Models (Izmailov et al., 2020; Ardizzone et al., 2020; Hagemann & Neumayer, 2021) or learned accept/reject sampling (Stimper et al., 2022). We introduce piecewise normalizing flows which divide the target distribution into clusters, with topologies that better match the standard normal base distribution, and train a series of flows to model complex multi-modal targets. We demonstrate the performance of the piecewise flows using some standard benchmarks and compare the accuracy of the flows to the approach taken in Stimper et al. (2022) for modelling multi-modal distributions. We find that our approach consistently outperforms the approach in Stimper et al. (2022) with a higher emulation accuracy on the standard benchmarks., Comment: 11 pages, 5 figures
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- 2023
30. Cosmic mysteries and the hydrogen 21-cm line: bridging the gap with lunar observations
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Fialkov, Anastasia, Gessey-Jones, Thomas, Dhandha, Jiten, Fialkov, Anastasia, Gessey-Jones, Thomas, and Dhandha, Jiten
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The hydrogen 21-cm signal is predicted to be the richest probe of the young Universe including eras known as the cosmic Dark Ages, the Cosmic Dawn when the first star and black hole formed, and the Epoch of Reionization. This signal holds the key to deciphering processes that take place at the early stages of cosmic history. In this opinion piece, we discuss the potential scientific merit of lunar observations of the 21-cm signal and their advantages over more affordable terrestrial efforts. The moon is a prime location for radio cosmology which will enable precision observations of the low-frequency radio sky. The uniqueness of such observations is that they will provide an unparalleled opportunity to test cosmology and the nature of dark matter using the Dark Ages 21-cm signal. No less enticing is the opportunity to obtain a much clearer picture of Cosmic Dawn than what is achievable from the ground, which will allow us to probe properties of the first stars and black holes., Comment: 15 pages, 3 figures, accepted for publication in Philosophical Transactions A
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- 2023
31. Quantifying the Water‐to‐Melt Mass Ratio and Its Impact on Eruption Plumes During Explosive Hydromagmatic Eruptions
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Hajimirza, Sahand, Jones, Thomas J., Moreland, William M., Gonnermann, Helge M., Thordarson, Thor, Hajimirza, Sahand, Jones, Thomas J., Moreland, William M., Gonnermann, Helge M., and Thordarson, Thor
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The interaction of magma with external water commonly enhances magma fragmentation through the conversion of thermal to mechanical energy and results in an increased production of fine-grained volcanic tephra. Magma-water interaction is thus of importance for hazard mitigation on both a local and a regional scales. The relative proportion of water that interacts with magma, quantified as the water-to-melt mass ratio, is thought to determine the efficiency of thermal to mechanical energy conversion, termed the fragmentation efficiency. Here, we analyze the pyroclast size distributions from the 10th century Eldgjá fissure eruption in Iceland, where parts of the fissure erupted subglacially and other erupted subaerially. The subglacially erupted magma passed through a column of glacial meltwater, resulting in a larger proportion of finer pyroclast sizes relative to the subaerially erupted, purely magmatic tephra. This finer grain size distribution has been attributed to quench-granulation induced by enhanced cooling upon interaction with external water. We hypothesize that the additional fragmentation (surface) energy required to produce the finer grained hydromagmatic deposits is due to the conversion of thermal to mechanical energy associated with the entrainment of water into the volcanic jet, as it passed through a column of subglacial melt water. Based on field and granulometry data, we estimate that the interaction of the volcanic jet with the meltwater provided an additional fragmentation energy of approximately 3–14 kJ per kg of pyroclasts. We numerically model the hydrofragmentation energy within a jet that passes through a layer of meltwater. We find that the water-to-melt mass ratio of entrained water required to produce the additional fragmentation energy is in the range of 1–2, which requires a minimum ice melting rate of 104 m3 s−1. Our simulation results show that the water-to-melt ratio is an important parameter that controls the ascent of plume in the
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- 2022
32. Inflated pyroclasts in proximal fallout deposits reveal abrupt transitions in eruption behaviour
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Jones, Thomas J., Moigne, Yannick Le, Russell, James K., Williams-Jones, Glyn, Giordano, Daniele, Dingwell, Donald B., Jones, Thomas J., Moigne, Yannick Le, Russell, James K., Williams-Jones, Glyn, Giordano, Daniele, and Dingwell, Donald B.
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During explosive eruption of low viscosity magmas, pyroclasts are cooled predominantly by forced convection. Depending on the cooling efficiency relative to other timescales, a spectrum of deposits can be formed. Deposition of hot clasts, above their glass transition temperature, can form spatter mounds, ramparts and clastogenic lava flows. Clasts may also be deposited cold, producing tephra cones and blankets. Thus, the deposit and pyroclast type can provide information about eruption dynamics and magma properties. Here we examine pyroclasts from Tseax volcano, British Columbia, Canada. These newly identified inflated pyroclasts, are fluidal in form, have undergone post-depositional expansion, and are found juxtaposed with scoria. Detailed field, chemical and textural observations, coupled with high temperature rheometry and thermal modelling, reveal that abrupt transitions in eruptive behaviour — from lava fountaining to low-energy bubble bursts — created these pyroclastic deposits. These findings should help identify transitions in eruptive behaviour at other mafic volcanoes worldwide.
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- 2022
33. Relationships Between Undergraduate Student Performance, Engagement, and Attendance in an Online Environment
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Jones, Thomas J. and Jones, Thomas J.
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Monitoring student attendance and engagement is common practice during undergraduate courses at university. Attendance data typically show a strong positive relationship with student performance and regular monitoring is an important tool to identify students who may require additional academic provisions, wellbeing support and pastoral care, for example. However, most of the previous studies and our framework for monitoring attendance and engagement is based on traditional on-campus, in-person delivery. Accelerated by the COVID-19 pandemic, our transition to online teaching delivery requires us to re-evaluate what constitutes attendance and engagement in a purely online setting and what are the most accurate ways of monitoring. Here, I show how statistics derived from student interaction with a virtual learning environment, Canvas, can be used as a monitoring tool. I show how basic statistics such as the number and frequency of page views are not adequate and do not correlate with student performance. A more in-depth analysis of video viewing duration, rather than simple page clicks/views is required, and weakly correlates with student performance. Lastly, I provide a discussion of the potential pitfalls and advantages of collecting such data and provide a perspective on some of the associated challenges.
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- 2022
34. Using multivariate data analysis to project performance in biathletes and cross-country skiers
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Jones, Thomas W., Wanner, Jeremy, Laaksonen, Marko, McGawley, Kerry, Jones, Thomas W., Wanner, Jeremy, Laaksonen, Marko, and McGawley, Kerry
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Previous research has indicated that pacing strategies within biathlon are influenced by terrain. However, it is not known if biathletes shooting performance within competition influences any pacing strategies employed. As such, the purpose of this study was to assess the impact of shooting performance on skiing speed and pacing strategies within sprint and individual competitionin elite female biathletes. Global navigation satellite system (GNSS) and heart data were collected during the female sprint and individual competitions of the 2019 IBU World Championships. Eight female biathletes (age 27 ± 2 years, IBU points 45 ± 18) competing in the sprint and individual events of the 2019 IBU World Championships volunteered and gave their written informed consent to participate in the study. Statistical analyses were conducted on shooting bout accuracy and speed and GNSS data to determine whether the accuracy and speed of the shooting bout influenced skiing speed in the subsequent lap of the race. No significant differences in skiing speed nor pacing strategies were observed subsequent to accurate or inaccurate shooting bouts, furthermore no significant differences in skiing speed were observed subsequent to fast or slow shooting bouts. As such, it appears in the biathletes assessed here, skiing speed and pacing was independent of shooting performance, although this was observed in a small sample of female biathletes.
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- 2022
35. Performance of a prototype TORCH time-of-flight detector
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Bhasin, Srishti, Blake, Thomas, Brook, Nicholas, Cicala, Maria Flavia, Conneely, Thomas, Cussans, David, van Dijk, Maarten, Forty, Roger, Frei, Christoph, Gabriel, Emmy, Gao, Rui, Gershon, Timothy, Gys, Thierry, Hadavizadeh, Tom, Hancock, Thomas, Jones, Thomas, Harnew, Neville, Kreps, Michal, Milnes, James, Piedigrossi, Didier, Rademacker, Jonas, Smallwood, Jennifer Clare, Bhasin, Srishti, Blake, Thomas, Brook, Nicholas, Cicala, Maria Flavia, Conneely, Thomas, Cussans, David, van Dijk, Maarten, Forty, Roger, Frei, Christoph, Gabriel, Emmy, Gao, Rui, Gershon, Timothy, Gys, Thierry, Hadavizadeh, Tom, Hancock, Thomas, Jones, Thomas, Harnew, Neville, Kreps, Michal, Milnes, James, Piedigrossi, Didier, Rademacker, Jonas, and Smallwood, Jennifer Clare
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TORCH is a novel time-of-flight detector, designed to provide charged particle identification of pions, kaons and protons in the momentum range 2-20 GeV/c over a 9.5 m flight path. A detector module, comprising a 10mm thick quartz plate, provides a source of Cherenkov photons which propagate via total internal reflection to one end of the plate. Here, the photons are focused onto an array of custom-designed Micro-Channel Plate Photo-Multiplier Tubes (MCP-PMTs) which measure their positions and arrival times. The target time resolution per photon is 70 ps which, for 30 detected photons per charged particle, results in a 10-15 ps time-of-flight resolution. A 1.25 m length TORCH prototype module employing two MCP-PMTs has been developed, and tested at the CERN PS using a charged hadron beam of 8 GeV/c momentum. The construction of the module, the properties of the MCP-PMTs and the readout electronics are described. Measurements of the collected photon yields and single-photon time resolutions have been performed as a function of particle entry points on the plate and compared to expectations. These studies show that the performance of the TORCH prototype approaches the design goals for the full-scale detector., Comment: 18 pages, 16 figures, to be published in Nucl. Instrum. Methods A. During review, clarity added to description throughout; updated figures 15 and 16; revised argument in section 6.3
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- 2022
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36. Reintervention and Survival After Transcatheter Pulmonary Valve Replacement
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McElhinney, Doff B., Zhang, Yulin, Levi, Daniel S., Georgiev, Stanimir, Biernacka, Elzbieta Katarzyna, Goldstein, Bryan H., Shahanavaz, Shabana, Qureshi, Athar M., Cabalka, Allison K., Bauser-Heaton, Holly, Torres, Alejandro J., Morray, Brian H., Armstrong, Aimee K., Millan-Iturbe, Oscar, Peng, Lynn F., Aboulhosn, Jamil A., Ruzyllo, Witold, Berger, Felix, Sondergaard, Lars, Schranz, Dietmar, Cheatham, John P., Jones, Thomas K., Ewert, Peter, Schubert, Stephan, McElhinney, Doff B., Zhang, Yulin, Levi, Daniel S., Georgiev, Stanimir, Biernacka, Elzbieta Katarzyna, Goldstein, Bryan H., Shahanavaz, Shabana, Qureshi, Athar M., Cabalka, Allison K., Bauser-Heaton, Holly, Torres, Alejandro J., Morray, Brian H., Armstrong, Aimee K., Millan-Iturbe, Oscar, Peng, Lynn F., Aboulhosn, Jamil A., Ruzyllo, Witold, Berger, Felix, Sondergaard, Lars, Schranz, Dietmar, Cheatham, John P., Jones, Thomas K., Ewert, Peter, and Schubert, Stephan
- Abstract
BACKGROUND Transcatheter pulmonary valve (TPV) replacement (TPVR) has become the standard therapy for postoperative pulmonary outflow tract dysfunction in patients with a prosthetic conduit/valve, but there is limited information about risk factors for death or reintervention after this procedure.OBJECTIVES This study sought to evaluate mid- and long-term outcomes after TPVR in a large multicenter cohort.METHODS International registry focused on time-related outcomes after TPVR.RESULTS Investigators submitted data for 2,476 patients who underwent TPVR and were followed up for 8,475 patient-years. A total of 95 patients died after TPVR, most commonly from heart failure (n = 24). The cumulative incidence of death was 8.9% (95% CI: 6.9%-11.5%) 8 years after TPVR. On multivariable analysis, age at TPVR (HR: 1.04 per year; 95% CI: 1.03-1.06 per year; P < 0.001), a prosthetic valve in other positions (HR: 2.1; 95% CI: 1.2-3.7; P = 0.014), and an existing transvenous pacemaker/implantable cardioverter-defibrillator (HR: 2.1; 95% CI: 1.3-3.4; P = 0.004) were associated with death. A total of 258 patients underwent TPV reintervention. At 8 years, the cumulative incidence of any TPV reintervention was 25.1% (95% CI: 21.8%-28.5%) and of surgical TPV reintervention was 14.4% (95% CI: 11.9%-17.2%). Risk factors for surgical reintervention included age (0.95 per year [95% CI: 0.93-0.97 per year]; P < 0.001), prior endocarditis (2.5 [95% CI: 1.4-4.3]; P = 0.001), TPVR into a stented bioprosthetic valve (1.7 [95% CI: 1.2-2.5]; P = 0.007), and postimplant gradient (1.4 per 10 mm Hg [95% CI: 1.2-1.7 per 10 mm Hg]: P < 0.001).CONCLUSIONS These findings support the conclusion that survival and freedom from reintervention or surgery after TPVR are generally comparable to outcomes of surgical conduit/valve replacement across a wide age range. (C) 2022 by the American College of Cardiology Foundation.
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- 2022
37. Intracluster magnetic filaments and an encounter with a radio jet
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Rudnick, Lawrence, Bruggen, Marcus, Brunetti, Gianfranco, Cotton, William, Forman, William, Jones, Thomas W., Nolting, Chris, Schellenberger, Gerrit, van Weeren, Reinout, Rudnick, Lawrence, Bruggen, Marcus, Brunetti, Gianfranco, Cotton, William, Forman, William, Jones, Thomas W., Nolting, Chris, Schellenberger, Gerrit, and van Weeren, Reinout
- Abstract
Thin synchrotron-emitting filaments are increasingly seen in the intracluster medium (ICM). We present the first example of a direct interaction between a magnetic filament, a radio jet, and a dense ICM clump in the poor cluster Abell 194. This enables the first exploration of the dynamics and possible histories of magnetic fields and cosmic rays in such filaments. Our observations are from the MeerKAT Galaxy Cluster Legacy Survey and the LOFAR Two Metre Sky Survey. Prominent 220 kpc long filaments extend east of radio galaxy 3C40B, with very faint extensions to 300 kpc, and show signs of interaction with its northern jet. They curve around a bend in the jet and intersect the jet in Faraday depth space. The X-ray surface brightness drops across the filaments; this suggests that the relativistic particles and fields contribute significantly to the pressure balance and evacuate the thermal plasma in a $\sim$35 kpc cylinder. We explore whether the relativistic electrons could have streamed along the filaments from 3C40B, and present a plausible alternative whereby magnetized filaments are a) generated by shear motions in the large-scale, post-merger ICM flow, b) stretched by interactions with the jet and flows in the ICM, amplifying the embedded magnetic fields, and c) perfused by re-energized relativistic electrons through betatron-type acceleration or diffusion of turbulently accelerated ICM cosmic ray electrons. We use the Faraday depth measurements to reconstruct some of the 3D structures of the filaments and of 3C40A and B., Comment: Accepted for publication in ApJ. 32 pages, 28 figures. Each of the last four figures has a corresponding movie file (mpeg), available under the Ancillary Files associated with this preprint
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- 2022
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38. Plasma physics of the intracluster medium
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Kunz, Matthew W., Jones, Thomas W., Zhuravleva, Irina, Kunz, Matthew W., Jones, Thomas W., and Zhuravleva, Irina
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This Chapter provides a brief tutorial on some aspects of plasma physics that are fundamental to understanding the dynamics and energetics of the intracluster medium (ICM). The tutorial is split into two parts: one that focuses on the thermal plasma component -- its stability, viscosity, conductivity, and ability to amplify magnetic fields to dynamical strengths via turbulence and other plasma processes; and one that focuses on the non-thermal population of charged particles known as cosmic rays -- their acceleration, re-acceleration, and transport throughout the cluster volume. Observational context is woven throughout the narrative, from constraints on the strength and geometry of intracluster magnetic fields and the effective viscosity of the ICM, to examples of radio halos, radio relics, and cluster shocks that can test theories of particle acceleration. The promise of future X-ray missions to probe intracluster turbulence and discover the impact of small-scale plasma physics, coupled with sensitive, high-resolution radio observations of synchrotron-emitting plasma that reveal the properties of intracluster magnetic fields and particle-acceleration mechanisms, are likely to establish galaxy clusters as the premier cosmic laboratories for deciphering the fundamental physics of hot, dilute plasmas., Comment: This Chapter will appear in the Section "Galaxy Clusters" (Section Editors: E. Pointecouteau, E. Rasia, A. Simionescu) of the "Handbook of X-ray and Gamma-ray Astrophysics" (Editors in chief: C. Bambi and A. Santangelo)
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- 2022
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39. Picosecond timing of charged particles using the TORCH detector
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Cicala, Maria Flavia, Bhasin, Srishti, Blake, Thomas, Brook, Nick H., Conneely, Thomas, Cussans, David, van Dijk, Maarten W. U., Forty, Roger, Frei, Christoph, Gabriel, Emmy P. M., Gao, Rui, Gershon, Timothy, Gys, Thierry, Hadavizadeh, Thomas, Hancock, Thomas Henry, Harnew, Neville, Jones, Thomas, Kreps, Michal, Milnes, James, Piedigrossi, Didier, Rademacker, Jonas, Smallwood, Jennifer Clare, Cicala, Maria Flavia, Bhasin, Srishti, Blake, Thomas, Brook, Nick H., Conneely, Thomas, Cussans, David, van Dijk, Maarten W. U., Forty, Roger, Frei, Christoph, Gabriel, Emmy P. M., Gao, Rui, Gershon, Timothy, Gys, Thierry, Hadavizadeh, Thomas, Hancock, Thomas Henry, Harnew, Neville, Jones, Thomas, Kreps, Michal, Milnes, James, Piedigrossi, Didier, Rademacker, Jonas, and Smallwood, Jennifer Clare
- Abstract
TORCH is a large-area, high-precision time-of-flight (ToF) detector designed to provide charged-particle identification in the 2-20 GeV$/c$ momentum range. Prompt Cherenkov photons emitted by charged hadrons as they traverse a 10mm quartz radiator are propagated to the periphery of the detector, where they are focused onto an array of micro-channel plate photomultiplier tubes (MCP-PMTs). The position and arrival times of the photons are used to infer the particles' time of entry in the radiator, to identify hadrons based on their ToF. The MCP-PMTs were developed with an industrial partner to satisfy the stringent requirements of the TORCH detector. The requirements include a finely segmented anode, excellent time resolution, and a long lifetime. Over an approximately 10m flight distance, the difference in ToF between a kaon and a pion with 10GeV$/c$ momentum is 35ps, leading to a 10-15ps per track timing resolution requirement. On average 30 photons per hadron are detected, which translates to a single-photon time resolution of 70ps. The TORCH research and development program aims to demonstrate the validity of the detector concept through laboratory and beam tests, results from which are presented. A timing resolution of 70-100ps was reached in beam tests, approaching the TORCH design goal. Laboratory timing tests consist of operating the MCP-PMTs coupled to the TORCH readout electronics. A time resolution of about 50ps was measured, meeting the TORCH target timing resolution., Comment: Vienna Instrumentation Conference 2022 proceedings. 13 pages,5 figures, 1 table
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- 2022
40. An Analysis of Warm-Up Strategies at a Cross-Country Skiing National Championship
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Jones, Thomas W., Govus, Andrew D., Buskqvist, Alfred, Andersson, Erik P., McGawley, Kerry, Jones, Thomas W., Govus, Andrew D., Buskqvist, Alfred, Andersson, Erik P., and McGawley, Kerry
- Abstract
Purpose: To provide a descriptive analysis of the warm-up (WU) strategies employed by cross-country skiers prior to distance and sprint competitions at a national championship and to compare the skiers' planned and executed WUs prior to the respective competitions. Methods: Twenty-one national- and international-level skiers (11 women and 10 men) submitted WU plans prior to the distance and sprint competitions, and after the competitions, reported any deviations from the plans. Skiers used personal monitors to record heart rate (HR) during WU, races, and cooldown. Quantitative statistical analyses were conducted on WU durations, durations in HR-derived intensity zones, and WU loads. Qualitative analyses were conducted on skiers' WU plans and their reasons for deviating from the plans. Results: Skiers' planned WUs were similar in content and planned time in HR-derived intensity zones for both the distance and sprint competitions. However, 45% of the women and 20% of the men reported that their WU was not carried out as planned, with reasons detailed as being due to incorrect intensities and running out of time. WU activities including skiing across variable terrain, muscle-potentiating exercises, and heat-maintenance strategies were missing from the skiers' planned routines. Conclusions: Skiers favored a long, traditional WU approach for both the sprint and distance events, performing less high-intensity and more moderate-intensity exercise during their WUs than planned. In addition, elements likely relevant to successful performance in cross-country skiing were missing from WU plans.
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- 2022
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41. Electromechanics and MEMS
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Jones, Thomas B. and Nenadic, Nenad G.
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- 2013
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42. A Companion to the Mountain Barometer
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Jones, Thomas
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- 2012
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43. Lived Experiences and Reflections of Joint NCATE-State Reviews.
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Samaras, Anastasia P., Francis, Shari L., Holt, Yvonne D., Jones, Thomas W., Martin, David S., Thompson, Joan L., and Tom, Alan R.
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Teacher education faculty members, state certification officers, and National Council for Accreditation of Teacher Education (NCATE) staff share what they have learned from their NCATE-state joint review and accreditation visits, noting dilemmas concerning the joint review (e.g., proactive versus reactive measures, issues of partnership versus separateness, and process versus product frameworks in planning and documenting growth). (SM)
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- 1999
44. Day and Night M.C.E.
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Jones, Thomas, Jones, Thomas, Jones, Thomas, and Jones, Thomas
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This music score was submitted for the Kaleidoscope 2020 Call for Scores, an open access collaboration with the UCLA Music Library.
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- 2020
45. Sing
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Jones, Thomas, Jones, Thomas, Jones, Thomas, and Jones, Thomas
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This music score was submitted for the Kaleidoscope 2020 Call for Scores, an open access collaboration with the UCLA Music Library.
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- 2020
46. Villanelle
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Jones, Thomas, Jones, Thomas, Jones, Thomas, and Jones, Thomas
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This music score was submitted for the Kaleidoscope 2020 Call for Scores, an open access collaboration with the UCLA Music Library.
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- 2020
47. Amsterdam’s Zero-Waste City Ho(s)tel: Re-imagining the building materials industry to meet the challenges of the 21st century
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Jones, Thomas (author) and Jones, Thomas (author)
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Jordaan’s Driehoekstraat Hostel targets a group of people that are intent on learning more about material consumption and shared knowledge potentials for more sustainable living. The building and its architecture aims to underline the sustainable values that will lead Amsterdam and various other European cities into a new circular economy. Its guests will co-habit and join together as part of a learning experience that explores a new route into sustainable tourism. A strong emphasis on reuse of building products and materials is imperative to show the public and necessary organisations that there is an urgent need for a shift in the resource efficiency discourse in the Netherlands. By reusing and repurposing different elements and materials, buildings, such as Hotels or Hostels, can be justified for their implementation into city models. The chosen site (Driehoekstraat, Jordaan) was intentional to show how such a building could operate and influence the conditions of a neighbourhood and its attitude towards its new economic system., City Hotel, Architecture, Urbanism and Building Sciences | Interiors Buildings Cities
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- 2021
48. Post-qualification admissions reform : government consultation
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Wilson, Philip, Craig, Kate, Julings, Martha, Jones, Thomas, Wilson, Philip, Craig, Kate, Julings, Martha, and Jones, Thomas
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- 2021
49. Multicenter Study of Endocarditis After Transcatheter Pulmonary Valve Replacement
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McElhinney, Doff B., Zhang, Yulin, Aboulhosn, Jamil A., Morray, Brian H., Biernacka, Elżbieta Katarzyna, Qureshi, Athar M., Torres, Alejandro J., Shahanavaz, Shabana, Goldstein, Bryan H., Cabalka, Allison K., Bauser-Heaton, Holly, Georgiev, Stanimir, Berger, Felix, Millan-Iturbe, Oscar, Peng, Lynn F., Armstrong, Aimee K., Levi, Daniel S., Fronczak-Jakubczyk, Aneta, Sondergaard, Lars, Anderson, Jason H., Schranz, Dietmar, Jones, Thomas K., Cheatham, John P., Schubert, Stephan, Ewert, Peter, McElhinney, Doff B., Zhang, Yulin, Aboulhosn, Jamil A., Morray, Brian H., Biernacka, Elżbieta Katarzyna, Qureshi, Athar M., Torres, Alejandro J., Shahanavaz, Shabana, Goldstein, Bryan H., Cabalka, Allison K., Bauser-Heaton, Holly, Georgiev, Stanimir, Berger, Felix, Millan-Iturbe, Oscar, Peng, Lynn F., Armstrong, Aimee K., Levi, Daniel S., Fronczak-Jakubczyk, Aneta, Sondergaard, Lars, Anderson, Jason H., Schranz, Dietmar, Jones, Thomas K., Cheatham, John P., Schubert, Stephan, and Ewert, Peter
- Abstract
Background: Endocarditis has emerged as one of the most impactful adverse events after transcatheter pulmonary valve replacement (TPVR), but there is limited information about risk factors for and outcomes of this complication. Objectives: The purpose of this study was to evaluate risk factors for and outcomes of endocarditis in a large multicenter cohort. Methods: The authors established an international registry focused on characterizing endocarditis after TPVR, including the incidence, risk factors, characteristics, and outcomes. Results: Investigators submitted data for 2,476 patients who underwent TPVR between July 2005 and March 2020 and were followed for 8,475 patient-years. In total, 182 patients were diagnosed with endocarditis a median of 2.7 years after TPVR, for a cumulative incidence of 9.5% (95% CI: 7.9%-11.1%) at 5 years and 16.9% (95% CI: 14.2%-19.8%) at 8 years (accounting for competing risks: death, heart transplant, and explant) and an annualized incidence of 2.2 per 100 patient-years. Staphylococcus aureus and Viridans group Streptococcus species together accounted for 56% of cases. Multivariable analysis confirmed that younger age, a previous history of endocarditis, and a higher residual gradient were risk factors for endocarditis, but transcatheter pulmonary valve type was not. Overall, right ventricular outflow tract (RVOT) reintervention was less often to treat endocarditis than for other reasons, but valve explant was more often caused by endocarditis. Endocarditis was severe in 44% of patients, and 12 patients (6.6%) died, nearly all of whom were infected with Staphylococcus aureus. Conclusions: The incidence of endocarditis in this multicenter registry was constant over time and consistent with prior smaller studies. The findings of this study, along with ongoing efforts to understand and mitigate risk, will be critical to improve the lifetime management of patients with heart disease involving the RVOT. Although endocarditis can be a
- Published
- 2021
50. Anthropometric, Physiological, and Performance Developments in Cross-country Skiers
- Author
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Jones, Thomas W., Lindblom, Hampus, Karlsson, Øyvind, Andersson, Erik, McGawley, Kerry, Jones, Thomas W., Lindblom, Hampus, Karlsson, Øyvind, Andersson, Erik, and McGawley, Kerry
- Abstract
Purpose This study aimed to describe changes in laboratory-assessed anthropometric and physiological characteristics, training volumes, and competitive performance in national development-team cross-country skiers over a 25-month period, and to analyze whether changes in competitive performance could be predicted by changes in laboratory-assessed qualities and training volumes. Methods Data collected over 25 months from 30 national development-team cross-country skiers (14 women, 16 men; age, 18–23 yr) were analyzed retrospectively using multivariate statistics. Anthropometric and physiological characteristics were assessed via dual-energy x-ray absorptiometry and incremental roller-ski treadmill tests, respectively. Total training volumes and distributions of low- and high-intensity training were analyzed from online training diaries, and competitive performance was determined by International Ski Federation (FIS) distance and sprint points. Results Whole- and upper-body lean mass increased in the full cohort of skiers (n = 30; both P < 0.05), whereas lower-body lean mass, whole-body fat mass, speed and oxygen uptake (V˙O2) at a blood lactate concentration (BLa) of 2 and 4 mmol·L−1, as well as time-trial completion time, power output, and peak V˙O2, improved in the women only (all P < 0.05). Valid predictive models were identified for female skiers’ best FIS distance points (R2 = 0.81/Q2 = 0.51) and changes in FIS distance points (R2 = 0.83/Q2 = 0.54), with body mass, fat mass, lean mass, V˙O2peak, and speed at a BLa of 4 mmol·L−1 identified as consistently important variables for projection. Conclusions The valid prediction of competitive performance was achieved for women only in distance events. This study suggests that improvements in body composition and aerobic capacity may be more beneficial for elite female development-level skiers than for their male counterparts. These results have implications for athlete selection and performance development.
- Published
- 2021
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