9 research outputs found
L’intensité compétitive appliquée au cyclisme : Modélisation et impacts potentiels sur l’organisation des courses professionnelles
No full textCompetitive balance is a concept having led to numerous studies in sports economics. Recently, it has been completed by the concept of competitive intensity. Nevertheless, these notions have been developed essentially for team sports. This article suggests a model of competitive intensity adapted to cycling. Based on the fact that individual performance is the most important in this sport, the model takes into account three elements which generate competitive intensity in the context of stage races: uncertainty for the general classification, uncertainty for the stage victory and attacks. After having detailed the calculations for each of these three elements, the competitive intensity of two stages with similar profile is compared so as to identify some factors which create uncertainty. The extension of this approach can help organisers in their choices for the routes to be favoured
Temporary organizational forms and coopetition in cycling: What makes a breakaway successful in the Tour de France?
No full textPurpose: In road cycling races, one of riders’ main objectives is to win stages, which most often requires breaking away from the pack of riders. What is it that makes a breakaway succeed, i.e. enable one of its members to win the stage? Design/methodology/approach: Descriptive statistics were computed and a logit model of breakaway success was estimated, based on a new kind of statistical data describing the development of each of the 268 breakaways that occurred in the 76 regular stages of the Tour de France 2013 to 2016. Findings: Breakaway success partly depends on the physics of cycling: breakaways are more successful when the stage is hilly or in mountain than flat. In addition, the likelihood of breakaway success depends on strategic moves such as attack timing and the percentage of riders with a teammate in the breakaway. Research limitations/implications: Understanding why certain breakaways succeed and others do not is useful to comprehend cycling performance and to help coopetitive temporary organizational forms such as breakaways optimize their strategic behavior. A limitation is the focus on the Tour de France only. Originality/value: The present study adds to the literature on temporary organizational forms, coopetition and cycling performance by analyzing within-stage data in cycling and, as such, enabling to capture its strategic dimension
Modeling Performances and Competitive Balance in Professional Road Cycling
No full textIn the economics of professional team sports leagues, the concept of competitive balance is well documented. It postulates the necessity of equilibrium between the teams in a league in order to guarantee uncertainty of outcome and thus generate public demand. By contrast, performances and competitive balance are not easy to define in road cycling. This is because cycling can be seen as a team sport but the global team performance usually is of minor importance or even not taken into account at all. A large proportion of cyclists are in support of another rider, meaning that they do not care about their personal result but instead try to help their team leader(s). Moreover, a team leader generally has one specific objective amongst a range of possible ones. This chapter deals with the complex issue of modeling performances and competitive balance in professional road cycling. After a brief review of the literature on modeling performances and competitive balance in cycling, an innovative measure is introduced: competitive intensity in cycling. We illustrate this measure with two stages of the 2013 and 2014 Tour de France, and we discuss its implications
Modeling performances and competitive balance in road cycling competitions
No full textIn the economics of professional team sports leagues, the concept of competitive balance is well documented. It postulates the necessity of equilibrium between the teams in a league in order to guarantee uncertainty of outcome and thus generate public demand. By contrast, performances and competitive balance are hard to define in road cycling. This is because cycling can be seen as a team sport but the overall team performance usually is of minor importance or even not taken into account at all. A large proportion of cyclists in a race take part in support of another rider, meaning that they do not care about their personal result but instead try to help their team leader(s). Moreover, a team leader generally has one specific objective among a range of possible ones. This chapter deals with the complex issue of modeling performances and competitive balance in professional road cycling. After a brief review of the literature on modeling performances and competitive balance in cycling, an innovative measure is introduced: competitive intensity in cycling. We illustrate this measure with two stages of the 2020 Tour de France, and we discuss its implications
Poster 254: Mechanical Response of ACL to Submaximal Fatigue Loading
No full textOBJECTIVES: It has been previously reported that the ACL increases in size and strength throughout rodent adolescence following both voluntary(1) and forced(2) endurance running. Here, we expand upon these findings to investigate how the ACL responds to submaximal fatigue loading. The ACL of sexually mature mice was subjected to 3 days of in vivo repetitive loading with an intervening day for recovery. We hypothesized that direct repetitive loading would should a greater positive change in ACL mechanical properties than what was previously observed following endurance running. To test this hypothesis, we designed a custom loading fixture to apply repetitive ACL loading cycles up to a predetermined percentage of the ACL failure load while approximating the knee kinematics of a jump-landing with a pivot shift. METHODS: With Institutional approval, 20 C57BL/6J 10-week-old female mice underwent ACL fatigue loading across 3 days with an intervening recovery day following each training session. For each loading session, the right rear leg of the mouse was placed in a custom loading fixture with the knee at 90° flexion and the sole of the foot at 20° inversion to induce a valgus moment across the knee (Fig. 1). Once positioned, the foreleg was internally rotated. Internal tibial rotation combined with a valgus moment across the knee generates maximum peak ACL strain and replicates a well characterized clinical ACL injury mechanism(3). Based on our previous in vivo work we chose two ACL ultimate tensile strength (UTS) loading percentages that represent low and moderate loads to repetitively fatigue the ligament. An in vivo 60% ACL UTS reliably generates collagen triple helix degradation followed by a proteoglycan response (Fig. 2), while no such changes occur at an in vivo 30% ACL UTS. Therefore, for each training session the ACL was cyclically loaded in vivo between 30% and 60% of ACL UTS for 440 cycles at a loading rate of 0.75 mm/s. After the third session mice were allowed to recover for 72 hrs. Following this, the tested and age-matched control ACLs were ruptured in vivo using the same knee kinematics at a loading rate of 2.7 N/s. All ACLs failed interstitially with there being no visible damage to other supporting knee ligaments or menisci. The resulting load-displacement curves were analyzed using custom MatLab code to quantify the mechanical properties of the fatigued and non-fatigued ACLs. In vivo measures quantified included ACL UTS, stiffness (S), total yield strength (TYS) and post-yield displacement (PYD). Data were analyzed using a two-way ANOVA with final body weight included as a covariate in order to determine the mechanical effect that the 3 days of submaximal fatigue loading had on the ACL compared to controls. RESULTS: The submaximal fatigue loading had a significant effect on ACL mechanical properties when compared to controls. Five mice suffered an ACL failure during the fatigue loading experiment, suggesting that 60% ACL UTS may be near the fatigue failure threshold in these mice. The remaining 15 mice that completed the fatigue study showed a 24.0% increase in UTS, a 26.8% increase in S, a 18.5% increase in TYS, and a 130.5% increase in post-yield displacement, compared to controls (Table 1). CONCLUSIONS: The outcomes of this study partially confirmed our hypothesis. Three days of direct repetitive loading elicited a greater ACL mechanical response than similar aged female mice following 4 weeks of endurance running. The marked improvement in ACL mechanics following repetitive training was likely due to the greater ACL loads experienced and the time allowed for tissue recovery. Rodent ligaments can turn collagen over in ˜24 hours(4). This suggests that the accumulation of degenerated ACL collagen triple helix structures was repaired during recovery for 75% of the mice. However, it also suggests that for some mice, ACL collagen degeneration was not repaired but rather accumulated and propagated hierarchically to the fibril and fiber level, resulting in tissue failure, as was previously observed in human cadaver knees subjected to submaximal ACL fatigue loading(5). This study further elucidates how the ACL responds to loading during adolescence. We have demonstrated that systematic repetitive ACL loading in adolescent mice can generate a positive mechanical response in the ACL. However, our findings also suggest that for a subset of mice participating in this training the submaximal fatigue load was too high and/or the duration of the recovery period was insufficient, resulting in catastrophic failure of the ligament prior to study completion. In the future, these failures should be able to be prevented by reducing the maximum load experienced by the ACL, increasing the duration of the recovery period, or both. If translatable to humans, these and future findings may assist clinicans in identifying potential risks for ACL injury related to an individual’s training intensity and help guide clinical inteventions. (1)Schlecht et al., J Orthop Res, 2019; (2)Cabaud et al., Am J Sports Med, 1980; (3)Wojtys et al., J Orthop Res, 2016; (4)Sodek, Arch Oral Biol, 1977; (5)Chen et al., Am J Sports Med, 2019
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The James Webb Space Telescope Mission
No full textTwenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least 4 m. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the 6.5 m James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 yr, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit. © 2023. The Author(s). Published by IOP Publishing Ltd on behalf of the Astronomical Society of the Pacific (ASP). All rights reserved.Open access articleThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
A comparative study of form and theology in the works of Flannery O'Connor and Simone Weil
No full textIn this comparative study of the form and theology of Flannery O'Connor and Simone Weil I interrogate how Weil's philosophical writings and her theology illuminate O'Connor's use of both narrative and non-fictional forms, and her Catholicism. The Introduction analyses how Weil's concept of superposed reading provides a new method of approaching both O'Connor, her writings, and O'Connor
studies, and focuses on how such apparently different women interconnect. Chapter One explores how both Weil and O'Connor attempt to write their theologies on the
souls of their readers yet are each subject to constraints imposed by form. Weil's concept of locating equilibrium between incommensurates is discussed, and her
distinctively philosophical approach to fictions and fictionality is used to investigate O'Connor's notion of prophetic fictions and the writer's role. Chapter Two assesses how both writers revivify Christian paradoxes. Weil's monstrous concept of affiiction, and O'Connor's use of the grotesque genre to jolt secular man into an
awareness of the sacred are scrutinised. Chapter Three studies how both writers consider an encounter between God and man is possible through the action of grace. My Conclusion interrogates how Weil's work can deepen our understanding of O'Connor's writings, and examines how successful O'Connor is at realising a truly
Christian literature. I conclude that despite being a writer of powerful fictions, O'Connor can not be totally successful in her mission as writer-prophet because
ultimately fiction escapes orthodoxy
The James Webb Space Telescope Mission
No full textTwenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least 4 m. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the 6.5 m James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 yr, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit
The James Webb Space Telescope Mission
No full textTwenty-six years ago a small committee report, building on earlier studies,
expounded a compelling and poetic vision for the future of astronomy, calling
for an infrared-optimized space telescope with an aperture of at least .
With the support of their governments in the US, Europe, and Canada, 20,000
people realized that vision as the James Webb Space Telescope. A
generation of astronomers will celebrate their accomplishments for the life of
the mission, potentially as long as 20 years, and beyond. This report and the
scientific discoveries that follow are extended thank-you notes to the 20,000
team members. The telescope is working perfectly, with much better image
quality than expected. In this and accompanying papers, we give a brief
history, describe the observatory, outline its objectives and current observing
program, and discuss the inventions and people who made it possible. We cite
detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space
Telescope Overview, 29 pages, 4 figure
