relative energy
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2022 ◽  
pp. 101269022110727
Author(s):  
Anna Posbergh

Women's sport remains a contested realm that frequently features standards and regulations premised on women's inferiority and physiological distinctions from men. In response to these purported sex-based differences, a range of protective policies have been implemented to ostensibly ensure women's safety and health, defend “fair competition” in women's sport, and/or prevent the violation of social and medical boundaries that define who is a “woman.” Yet, protective policies encompass a multitude of rationales and strategies, demonstrating the malleability of “protection” in terms of who is protected and why. In this article, I draw from Michel Foucault's theory of “governmentality” to investigate the nuances of protective policies, especially their placed importance on sex differences. To do so, I examine three case studies: World Athletics’ (WA) 2019 female eligibility policy, WA's 2019 transgender eligibility policy, and the International Olympic Committee's (IOC) consensus statement on relative energy deficiency in sport (RED-S). Using document texts and semi-structured interviews with eight scientists involved with developing the case studies, I find that protective policies are developed through messy and often contentious processes that selectively draw from varying knowledges and discourses. This then culminates in contrasting methods of defining, protecting, and governing women athletes and their bodies.


2022 ◽  
Vol 8 (1) ◽  
Author(s):  
Sebastian Kaufmann ◽  
Martin Ziegler ◽  
Jana Werner ◽  
Christine Noe ◽  
Richard Latzel ◽  
...  

Abstract Background Artistic gymnastics is a popular Olympic discipline where female athletes compete in four and male athletes in six events with floor exercise having the longest competition duration in Women’s and Men’s artistic gymnastics (WAG, MAG). To date no valid information on the energetics of floor gymnastics is available although this may be important for specific conditioning programming. This study evaluated the metabolic profile of a simulated floor competition in sub-elite gymnasts. Methods 17 (9 male, 8 female) sub-elite gymnasts aged 22.5 ± 2.6y took part in a floor-training-competition where oxygen uptake was measured during and until 15 min post-exercise. Additionally, resting and peak blood lactate concentration after exercise were obtained. The PCr-LA-O2 method was used to calculate the metabolic energy and the relative aerobic (WAER), anaerobic alactic (WPCr) and anaerobic lactic (WBLC) energy contribution. Further, the athletes completed a 30 s Bosco-jumping test, a countermovement jump and a drop jump. Results The competition scores were 9.2 (CI:8.9–9.3) in WAG and 10.6 (CI:10.4–10.9) in MAG. The metabolic profile of the floor routine was mainly aerobic (58.9%, CI: 56.0–61.8%) followed by the anaerobic alactic (24.2%, CI: 21.3–27.1%) and anaerobic lactic shares (16.9%, CI:14.9–18.8%). While sex had a significant (p = .010, d = 1.207) large effect on energy contribution, this was not the case for competition duration (p = .728, d = 0.061). Relative energy contribution of WAG and MAG differed in WAER (64.0 ± 4.7% vs. 54.4 ± 6.8%, p = .004, d = 1.739) but not in WPCr (21.3 ± 6.1% vs. 26.7 ± 8.0%, p = .144, d = 0.801) and WBLC (14.7 ± 5.4% vs. 18.9 ± 4.2%, p = .085, d = 0.954). Further no correlation between any energy share and performance was found but between WPCr and training experience (r = .680, p = .044) and WBLC and competition level (r = .668, p = .049). Conclusion The results show a predominant aerobic energy contribution and a considerable anaerobic contribution with no significant difference between anaerobic shares. Consequently, gymnastic specific aerobic training should not be neglected, while a different aerobic share in WAG and MAG strengthens sex-specific conditioning. All in all, the specific metabolic share must secure adequate energy provision, while relative proportions of the two anaerobic pathways seem to depend on training and competition history.


Author(s):  
Braeden T. Charlton ◽  
Sara Forsyth ◽  
David C. Clarke

The Female Athlete Triad (Triad) and the more encompassing Relative Energy Deficiency in Sport (RED-S) are disorders caused by low energy availability (LEA). LEA is a state of insufficient energy intake by an athlete relative to their energy expenditure. Persistent LEA results in the deleterious consequences to health and performance that comprise RED-S. With respect to both the Triad and RED-S, researchers have called for more education of those involved with sport, particularly coaches, to help reduce the incidence of these disorders. Recent studies have shown that as few as 15% of coaches are aware of the Triad, with up to 89% unable to identify even one of its symptoms. RED-S is a more recently established concept such that coach knowledge regarding it has only begun to be assessed, but the results of these initial studies indicate similar trends as for the Triad. In this review, we synthesize research findings from 1986 to 2021 that pertains to LEA and RED-S, which coaches should know so they can better guide their athletes.


2022 ◽  
Vol 17 (01) ◽  
pp. C01025
Author(s):  
B. Bergmann ◽  
P. Smolyanskiy ◽  
P. Burian ◽  
S. Pospisil

Abstract In the present work, we study the Timepix2 pixels’ high energy response in the so-called adaptive gain mode. Therefore, Timepix2 with a 500 μm thick silicon sensor was irradiated with protons of energies in the range from 400 keV to 2 MeV and α-particles of 5.5 MeV from 241Am. A novel method was developed to determine the energy deposit in single pixels of particle imprints, which are spread out over a set of neighbor pixels (cluster). We show that each pixel is capable of measuring the deposited energy from 4 keV up to ∼3.2 MeV. Reconstructing the full energy content of the clusters, we found relative energy resolutions ( σ E ) better than 2.7% and better than 4% for proton and α-particle data, respectively. In a simple experiment with a 5.5 MeV α-particle source, we demonstrate that energy losses in thin (organic) specimen can be spatially resolved, mapping out sample thickness variations, with a resolution around 1–2 μm, across the sensor area. The inherent spatial resolution of the device was determined to be 350 nm in the best case.


2022 ◽  
Vol 0 (0) ◽  
pp. 0
Author(s):  
Yu Liu ◽  
Ting Zhang

<p style='text-indent:20px;'>In this paper, we define a renormalized dissipative measure-valued (rDMV) solution of the compressible magnetohydrodynamics (MHD) equations with non-monotone pressure law. We prove the existence of the rDMV solutions and establish a suitable relative energy inequality. And we obtain the weak (measure-valued)-strong uniqueness property of this rDMV solution with the help of the relative energy inequality.</p>


2022 ◽  
pp. 295-309
Author(s):  
Karen M. Sutton ◽  
Sarah M. Cheney ◽  
Elizabeth A. Fierro ◽  
Ellen K. Casey

Polymers ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 112
Author(s):  
Ioannis Tsampanakis ◽  
Alvin Orbaek White

The inherent value and use of hydrocarbons from waste plastics and solvents can be extended through open-loop chemical recycling, as this process converts plastic to a range of non-plastic materials. This process is enhanced by first creating plastic–solvent combinations from multiple sources, which then are streamlined through a single process stream. We report on the relevant mechanics for streamlining industrially relevant polymers such as polystyrene (PS), polypropylene (PP), high-density polyethylene (HDPE), and acrylonitrile butadiene styrene (ABS) into chemical slurries mixed with various organic solvents such as toluene, xylene, and cyclohexane. The miscibility of the polymer feedstock within the solvent was evaluated using the Relative Energy Difference method, and the dissolution process was evaluated using the “Molecular theories in a continuum framework” model. These models were used to design a batch process yielding 1 tonne/h slurry by setting appropriate assumptions including constant viscosity of solvents, disentanglement-controlled dissolution mechanism, and linear increase in the dissolved polymer’s mass fraction over time. Solvent selection was found to be the most critical parameter for the dissolution process. The characteristics of the ideal solvent are high affinity to the desired polymer and low viscosity. This work serves as a universal technical guideline for the open-loop chemical recycling of plastics, avoiding the growth of waste plastic by utilising them as a carbon feedstock towards a circular economy framework.


Author(s):  
G.G. Panchenko

The work is devoted to methods of calculating the total energy intensity of fuel, currency, products, labor costs, raw materials and materials necessary for the practical application of energy-economic analysis of production efficiency. The article proposes a simplified methodology and performs calculations to estimate the total energy intensity of currency and products of seven sectors of the economy of Ukraine, which produce food, mineral, chemical, metallurgical and machine-building products, as well as services - transport and computer programming. Calculations were made for three types of fuel - nuclear fuel, coal and natural gas, which in 2017 accounted for more than 76% of total fuel consumption in Ukraine. The main components of the total energy intensity of the products of the national economy are due to the use of fuel for the production of fuel, electricity and heat and raw materials, as well as the cost of fuel for the production of products that workers buy for wages. The article identifies the relative energy and economic efficiency of fuel use in the economy of Ukraine


2021 ◽  
Author(s):  
Davide Silvagni ◽  
Jim L Terry ◽  
William McCarthy ◽  
Amanda E Hubbard ◽  
Thomas Eich ◽  
...  

Abstract In some conditions, I-mode plasmas can feature pedestal relaxation events (PREs) that transiently enhance the energy reaching the divertor target plates. To shed light on their appearance, characteristics and energy reaching the divertor targets, a comparative study between two tokamaks – Alcator C-Mod and ASDEX Upgrade – is carried out. It is found that PREs appear only in a subset of I-mode discharges, mainly when the plasma is close to the H-mode transition. Also, a growing oscillating precursor before the PRE onset is observed in the region close to the separatrix in both devices, and a discussion on a possible triggering mechanism is outlined. The PRE relative energy loss from the confined region is found to increase with decreasing pedestal top collisionality ν* ped. Similarly, also the relative electron temperature drop at the pedestal top, which is related to the conductive energy loss, rises with decreasing ν* ped. Based on these relations, the PRE relative energy loss in future devices such as DEMO and ARC is estimated. Finally, the divertor peak energy fluence due to the PRE is measured on each device. Those values are then compared to the model introduced in [1] for type-I ELMs. The model is shown to provide an upper boundary for PRE energy fluence data, while a lower boundary is found by dividing the model by three. These two boundaries are used to make projections of the PRE divertor energy fluence to DEMO and ARC.


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