ABSTRACT Tracking long-term performance trends in both women’s and men’s sport can provide insight into the progression of female athletic performance and the contexts that shape it. This study examined results from 1,284 international events over the past 20 years in Canoe Sprint disciplines (Sprint Kayaking; KAY, Sprint Canoeing; CAN), and in Track Sprint Cycling (CYC), to benchmark the progression in women’s performance against men’s using the percentage difference in race times. We observed larger performance gaps in upper-body dominant disciplines (KAY ~14%, CAN ~ 20%) than in the lower-body dominant CYC (~11%). Notably, in CAN – where women’s elite-level inclusion has been more recent – performance gaps were both larger and continued to narrow over time. In contrast, KAY and CYC showed relatively stable differences, aligning with longer histories of women’s participation. These findings suggest that observed size and stability of performance gaps reflect both physiological sex differences and the influence of sport-specific development pathways and access. Monitoring performance trajectories across both sexes may provide insight into whether sex differences reflect biological ceilings or are shaped by contextual inequities in opportunity and support.

The aim of this study was to assess the effects of oxygen availability (normoxia vs. hypoxia), muscle mass and exercise type on pulse oxygen saturation, and quadriceps muscle oxygenation during repeated sprint exercises. Sixteen healthy participants completed 5 12 s sprints (21 s rest). This sprint-like exercise was performed under two environmental conditions (normoxia: FiO2=21%; systemic hypoxia: FiO2=13%) and for three exercise modalities: unilateral knee extensions (KE) involving the right leg extensors (UNI), bilateral KE involving both legs extensors (BIL), and bilateral leg cycling (CYC). Measurements included power output, pulse oxygen saturation (SpO2), and vastus lateralis oxygenation (delta in tissue saturation index; ΔTSI). In hypoxia, a similar minimal SpO2 was reported in UNI and BIL but SpO2 was lower in CYC (p=0.047 and p=0.021). ΔTSI during sprints and recoveries were similar in UNI and BIL but greater in CYC (p<0.001) and in normoxia compared to hypoxia (main condition effect; p=0.002). The power output was lower during KE exercises than during cycling, and no effect of hypoxia has been reported. The main results of this study indicate that unilateral and bilateral KE at high intensity induce comparable pulse and local muscular desaturation in hypoxia, and that these alterations are exacerbated during cycling.

The purpose of this study was to determine whether chronic sport training comprising of low or nonimpact musculoskeletal loading in road cycling (CYC) and distance running (RUN) were associated with tibial and ulnar bending strength and calcaneus and wrist BMD in male athletes. Method. Study subjects included 12 road cyclists (CYC), 12 distance runners (RUN) and 12 physically active nonathletic (CON). Tibial and ulnar bending strength (EI, Nm2) were assessed using a mechanical response tissue analyzer (MRTA), and BMD (g/cm2) of the wrist and calcaneus were assessed using a peripheral X-ray absorptiometry. Group means differences among the study groups were determined using ANCOVA. Results. Ulnar bending strength (EI, Nm2) of CYC were higher than CON (62.0 ± 20 vs 44.7 ± 9 Nm2, p&lt; 0.05), but not RUN. Tibial bending strength (EI, Nm2) of CYC and RUN were not higher than CON. Calcaneus BMD of RUN was higher than CON (0.666 ± 0.07 vs 0.579 ± 0.06 g/m2, p&lt;0.05), but not CYC. Wrist BMD of CYC was not higher than (p = 0.07) RUN and CON. Conclusion. Chronic engagement in CYC training induces osteogenic adaptation for increased ulnar bending strength and RUN training induces increased calcaneus BMD.

Comparative Effectiveness of 4 Exercise Interventions Followed by 2 Years of Exercise Maintenance in Multiple Sclerosis: A Randomized Controlled Trial

Impact of the dynamic vegetation on climate extremes during the wheat growing period over China

A decline in skeletal muscle function is thought to be a key factor contributing to the decreased functional capacity and quality of life associated with aging. Although the exact mechanism is not fully understood, impaired mitochondrial and microvascular function are thought to play a major role. A complicating factor in determining the physiological mechanisms of aging is the fact that aging typically coincides with a decline in physical fitness due to lifestyle changes. PURPOSE: To evaluate age-related differences in skeletal muscle oxidative function using near-infrared spectroscopy (NIRS), and to examine the role of physical fitness. METHODS: Nineteen young (Y: 26.2 ± 3.0 yrs) and twenty elderly (E: 62.4 ± 4.3 yrs) adults participated in this study. Skeletal muscle oxidative function was evaluated during whole-body exercise (cycling) and isolated muscle work (handgrip exercise) using NIRS. Muscle oxyhemoglobin saturation (SmO2) was measured in the leg and forearm. Vascular occlusions were applied at rest and immediately following submaximal cycling (CY) and handgrip (HG) exercise bouts at various intensities. End-exercise SmO2 values were calculated as the average SmO2 values during the last 30 s of each work bout, and muscle oxygen consumption (mVO2) was derived from the initial linear decrease in SmO2 during vascular occlusions. RESULTS: No differences were found in resting mVO2 for leg or forearm (all P > 0.05). Submaximal CY work rates were similar at low intensity (E: 81 ± 28 W vs Y: 89 ± 25 W, P = 0.17), but significantly lower for the elderly during high intensity (E: 182 ± 59 W vs Y: 217 ± 49 W, P = 0.02). All four submaximal HG work rates were similar for Y and E (P > 0.05). Although SmO2 responses during both exercise modes were more pronounced in Y, no significant differences between Y and E were found in end-exercise SmO2 values or mVO2 (all P > 0.05). CONCLUSION: When exercising at roughly equal absolute and relative work rates, muscle function was similar in E and Y, both during whole body CY as well as during isolated HG exercise. Since absolute and relative work rates were reasonably similar for both groups, the results indicate that not aging, but physical fitness level might be the determinant for the decreased muscle function that is thought to accompany aging.

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The benefits of cycling

Did COVID19 teach cycling

Among different ways of harnessing tidal energy, tidal stream turbines are gaining popularity over traditional tidal dams. This is owing to the lower capital cost, and potentially lower ecological impact of tidal turbines. However, compared to more developed sources of energy, tidal energy remains expensive, which impedes its large-scale utilization. Significant reduction in the cost of energy can be achieved by reducing the maintenance expenses and improving the capacity factor. In other words, improving reliability can make tidal energy substantially cheaper. In this context, this thesis investigates a horizontal axis tidal turbine (HATT) power take-off system with a direct-drive generator. The focus of this thesis is on improving the reliability of the electrical subsystems in the HATT power take-off system. From this perspective, power converter and generator are the two most important components in the drive train. For the converter, the reliability improvement is analyzed from the objective of delaying the thermal cycling failure in the power semiconductor modules beyond the turbine lifetime. Whereas on the generator side, a flooded generator is investigated as a potentially more reliable alternative to conventional airgap generator.

Responses of soil water content, soil inorganic nitrogen, aboveground and belowground biomass, soil respiration, ecosystem respiration, net ecosystem production, and gross ecosystem production to precipitation variability from a 3-y manipulative experiment (2004-2016) and a 12-y model simulation (2000-2011).

The polyaniline nanowire/self-supported graphene (PANI/SGr) composite was synthesized by one-step electrochemical exfoliation and electrodeposition method using graphite paper. The directional migration of electrolyte ions and the electropolymerization of aniline monomers through the electrical field simultaneously occurred in the mixed solution including Na2SO4, HCl and aniline (An) monomers. The stability of the PANI/SGr composite is enhanced by the combination of the new-born SGr with high activity and PANI. The uniform distribution of the nanowire-like PANI is achieved on the surface of the SGr. The PANI nanowires lead to the formation of the three-dimensional network architecture, where the existence of pores facilitates the diffusion of electrolyte ions into the internal structure of the PANI/SGr composite. The electrochemical tests of the PANI/SGr composite were conducted as a supercapacitor electrode material. The specific capacitance of 453 F·g−1 at a scan rate of 2 mV·s−1 is achieved. The rate capability of the PANI/SGr composite at the current densities of 0.5-10 A·g−1 is up to 73.1%. The cycling stability of the PANI/SGr composite is as high as 87.3% after 10000 discharge-charge cycles at the current density of 1 A·g−1. All of these results indicate that the PANI/SGr composite possesses good capacitive performance and excellent cycling stability. The PANI/SGr composite is promising for supercapacitor electrode materials.

The existence of the Covid 19 pandemic makes cycling activities in big city people a way of life to maintain fitness. Cycling during the Covid 19 pandemic has increased because cycling is considered to be able to get rid of boredom at home, increase immunity, fill spare time, and increase energy in carrying out daily routines. This study aims to determine the community's motivation for cycling during the Covid 19 pandemic in the city of Surabaya. This research method is survey research. The population in this study were all people who like cycling in the city of Surabaya. The sample in this study were 400 people who have a hobby of cycling who were randomly selected. The instrument used was a questionnaire to measure intrinsic and extrinsic motivation. The results of this study indicate that 50% of the community's motivation for cycling is included in the very high criteria, 48% is included in the high criteria, 2% is included in the moderate category. Intrinsic motivation of the community to cycling by 47% is included in the very high criteria, 50% is included in the high criteria, and 3% is in the moderate category. 67% of the community's extrinsic motivation to cycle is included in the very high criteria, 32% is included in the high criteria, and 1% is in the moderate category.

The Sn-based materials have been a focus as promising high-capacity electrode materials of lithium-ion battery. However, its poor cycling performance has severely restricted the large-scale practical applications. The Sn quantum dot/graphene (SnQds/rGO) composite electrode material was synthesized by chemical reduction method, using graphene oxide as the carrier. The Sn quantum dots with <10 nm were uniformly loaded on the surface of graphene. The experimental results show that the SnQds/rGO composite with Sn mass fraction of 90wt% has good comprehensive electrochemical performance. The first discharge capacity and Coulomb efficiency of the SnQds/rGO composite are 939 mAh/g and 66.6%, respectively. It’s discapacity can reach 621 mAh/g after 200 cycles and the capacity retention rate is 66.1%. The structure stability of SnQds/rGO composite is improve, meanwhile its impedance reduce, owing to the commposite of small size Sn quantum dots and graphenethe. As a result, the cycle performance and rate performance of the SnQds/rGO composite have been significantly improved. However, the initial Coulomb efficiency of SnQds/rGO composite decreases.

We analyzed the feeding ecology of Cynoglossus joyneri by carbon and nitrogen stable isotope analysis based on the samples collected from the bottom trawl surveys during spring and autumn of 2018 in Haizhou Bay, China. The results showed that the δ13C and δ15N values of C. joyneri ranged from -20.75‰ to -15.91‰ and from 5.98‰ to 12.02‰, respectively. The mean values of the δ13C and δ15N were (-17.79±1.00)‰ and (9.37±1.33)‰, respectively. There was a significantly negative correlation between the δ13C values and standard length and a positive correlation between the δ15N values and standard length. The mean trophic level of C. joyneri was (3.43±0.97). There was a significantly positive correlation between the trophic level and standard length. The dominant prey groups of C. joyneri were fish, crabs, shrimps, mollusca, polychaeta, plankton and particle organic matter (POM). The trophic contribution of shrimps was the highest among these prey groups. The trophic contribution of fish, crabs and shrimps was higher in autumn than those in spring. This study would help to understand the role of C. joyneri in the material cycling and energy flow in Haizhou Bay ecosystem, and provide scientific basis for the protection and rational utilization of this species.

Establishing monoculture of native broadleaved tree species and mixed coniferous broadleaved plantations is the tendency for forest management in subtropical China. The variations of structure and function of soil bacterial community in monoculture and mixed tree plantations are still not clear. We examined soil bacterial community structure and function under different soil layers (0-20, 20-40 and 40-60 cm) in three planted forests, including broadleaved Castanopsis hystrix, coniferous Pinus massoniana and their mixed plantation, in south subtropical China, using 16S rRNA gene high-throughput sequencing and PICRUSt prediction. The results showed that soil bacterial community structure of mixed plantation and P. massoniana plantation were similar but being significant different from that in C. hystrix plantation. The diversity, biological pathways metabolic function, and nitrogen cycling function of soil bacterial community in C. hystrix plantation were lower than those in P. massoniana plantation and mixed plantation. Soil total nitrogen, nitrate nitrogen and C/N were the main factors driving the variations of soil bacterial community structure and function among different forest types. Our results suggested that the mixed plantation of C. hystrix and P. massoniana is better than C. hystrix plantation in this area in terms of soil bacterial community structure and function.

Due to their technological advantages, lithium-ion-batteries have been established in stationary and mobile applications. In general, for electrochemical storage systems, there is a fundamental conflict between high energy density and temporal high power density for different applications. During the electrode production process, the material- and process-related parameters define the resulting cell properties. In the last step of the electrode manufacturing, the compaction process, a high volume fraction of active material is targeted at the expense of internal porosity. In contrast, porosity is essential for the cell functionality, especially for kinetic requirements. Thus, tailoring the microstructure of the electrode active material results in an effcient design for different applications. The present work aims at investigating and correlating the microstructural changes by active mass compaction with the resulting electrochemical properties. For technologically favorable electrode active mass compositions, a wide compaction down to porosities of less than 20% was considered and electrochemically cycled between C/20 and 5C to map different applications. Microstructural analyses were used to determine the influence of compaction on the active material particles within the active mass and on the binder/additive phase. In addition to the change in pore size distribution, the studies give insight on the freely accessible surface of the active material particles within the porous active mass, the number of potential near-surface pores and pore openings with access to deeper lying areas and interactions on active mass components due to the external force application depending on the degree of compaction. The electrochemical properties of variously compacted LiNi1/3Co1/3Mn1/3O2 (NCM) and graphite electrodes were determined in half-cells with a Li/Li+ counter electrode and in fullcell configuration with a graphite or NCM counter electrodes of constant porosity to finally correlate them with the active mass microstructure. From the performed capacities, the specific energy vs. specific power (gravimetric consideration) and the energy density vs. power density (volumetric consideration) were displayed in Ragone plots. By using this result, an optimal porosity of the electrodes and, at the same time, an effcient trade-off of the target variables energy and power was achieved. Electrochemical long-term cycling also provided insights into the limitations of the electrode active masses depending on the degree of compaction in different applications. Focusing on the manufacturing parameters and microstructure of the active mass coating of lithium-ion cells, the present results give guidelines for the design optimization of electrodes for energy cells and power cells as well.

Persistent organic pollutant cycling in forests

As the title suggests, cyclists are the main topic of this dissertation and more specifically, their behaviour while they are ‘in motion’. The term ‘in motion’ is used in the title to represent microscopic operational cycling behaviour, which is the behaviour of cyclists, treated as individuals (microscopic level), while they are riding their bicycle and making decisions on how to interact with other traffic participants and with the infrastructure (operational level). Within this dissertation, models are developed to capture this behaviour using data collected for this purpose. Further empirical data analyses led to more behavioural insights and design recommendations were provided based on the findings. In this summary, each of these elements is shortly discussed, along with the need for this research.

The aim of the expedition CACOON Sea was to investigate the transition from fresh water to salt water and its impact on fate and quality on dissolved and particulate organic and inorganic carbon and nitrogen. This is in accordance with the main Changing Arctic Carbon cycle in the cOastal Ocean Near-shore (CACOON, https://www.changing-arctic-ocean.ac.uk/project/cacoon/) project goal to investigate the changing freshwater export and impact of terrestrial permafrost thaw into the near-shore zone of the Laptev Sea.