EFFECTS OF SHOE COLLAR HEIGHT ON SAGITTAL ANKLE ROM, KINETICS AND POWER OUTPUT DURING SINGLE-LEG AND DOUBLE-LEG JUMPS

The aim of this research was to examine the effects of high-top shoes and low-top shoes on sagittal ankle ROM, kinetics and power output during single-leg and double-leg jumps. Twelve male subjects were requested to wear high-top and low-top shoes to perform single-leg and double-leg jumps. Ankle joint kinematics and kinetics data were collected using Vicon system and force plates. Shoe collar heights did not influence the jump height in both single-leg and double-leg jump tasks. However, high-top shoes adopted in this study resulted in a significant smaller sagittal ankle ROM during a quasi-static movement. In addition, wearing high-top shoe could also decrease the dorsiflexion ankle joint torque and power output during the push-off phase in single-leg jump. These findings provide preliminary evidence suggesting that a changed ankle kinematic and kinetic behaviour in the sagittal plane may be induced when wearing high-top shoes

Exclusive production of double light neutral mesons at the e+e−e^+e^- colliders

In this work we investigate the exclusive production of a pair of light neutral mesons in $e^+e^-$ annihilation, where the final state bears an even $C$-parity. The production processes can be initiated via the photon fragmentation or the non-fragmentation mechanism. While the fragmentation contribution can be rigorously accounted, the non-fragmentation contributions are calculated within the framework of collinear factorization, where only the leading-twist light-cone distribution amplitudes (LCDAs) of mesons are considered. Mediately solely by the non-fragmentation mechanism, the production rates of double light neutral pseudoscalar mesons are too small to be observed at the commissioning $e^+e^-$ facilities. In contrast, the production rates of a pair of light neutral vector mesons are greatly amplified owing to the significant kinematic enhancement brought by the fragmentation mechanism. It is found that, at $\sqrt{s}=3.77$ GeV, after including the destructive interference between the non-fragmentation and fragmentation contributions, the production rates for $e^+e^-\to \rho^{0}\rho^{0}$ and $\rho^0\omega$ can be lowered by about 10\% and 30\% relative to the fragmentation predictions. Future precise measurement of these exclusive double neutral vector meson production channels at {\tt BESIII} experiment may provide useful constraints on the LCDAs of light vector mesons.Comment: 20 pages, 4 tables, 6 figure

Surface terraces in pure tungsten formed by high-temperature oxidation

We observe large-scale surface terraces in tungsten oxidised at high temperature and in high vacuum. Their formation is highly dependent on crystal orientation, with only {111} grains showing prominent terraces. Terrace facets are aligned with {100} crystallographic planes, leading to an increase in total surface energy, making a diffusion-driven formation mechanism unlikely. Instead we hypothesize that preferential oxidation of {100} crystal planes controls terrace formation. Grain height profiles after oxidation and the morphology of samples heat treated with limited oxygen supply are consistent with this hypothesis. Our observations have important implications for the use of tungsten in extreme environments.Comment: 10 pages, 4 figures & supplementar

Elastic strain associated with irradiation-induced defects in self-ion irradiated tungsten

Elastic interactions play an important role in controlling irradiation damage evolution, but remain largely unexplored experimentally. Using transmission electron microscopy (TEM) and high-resolution on-axis transmission Kikuchi diffraction (HR-TKD), we correlate the evolution of irradiation-induced damage structures and the associated lattice strains in self-ion irradiated pure tungsten. TEM reveals different dislocation loop structures as a function of sample thickness, suggesting that free surfaces limit the formation of extended defect structures that are found in thicker samples. HR-TKD strain analysis shows the formation of crystallographically-orientated long-range strain fluctuations above 0.01 dpa and a decrease of total elastic energy above 0.1 dpa

High-Fidelity Lake Extraction via Two-Stage Prompt Enhancement: Establishing a Novel Baseline and Benchmark

The extraction of lakes from remote sensing images is a complex challenge due to the varied lake shapes and data noise. Current methods rely on multispectral image datasets, making it challenging to learn lake features accurately from pixel arrangements. This, in turn, affects model learning and the creation of accurate segmentation masks. This paper introduces a unified prompt-based dataset construction approach that provides approximate lake locations using point, box, and mask prompts. We also propose a two-stage prompt enhancement framework, LEPrompter, which involves prompt-based and prompt-free stages during training. The prompt-based stage employs a prompt encoder to extract prior information, integrating prompt tokens and image embeddings through self- and cross-attention in the prompt decoder. Prompts are deactivated once the model is trained to ensure independence during inference, enabling automated lake extraction. Evaluations on Surface Water and Qinghai-Tibet Plateau Lake datasets show consistent performance improvements compared to the previous state-of-the-art method. LEPrompter achieves mIoU scores of 91.48% and 97.43% on the respective datasets without introducing additional parameters or GFLOPs. Supplementary materials provide the source code, pre-trained models, and detailed user studies.Comment: 8 pages, 7 figure

Hard-scattering approach to strongly hindered electric dipole transitions between heavy quarkonia

The conventional wisdom in dealing with electromagnetic transition between heavy quarkonia is the multipole expansion, when the emitted photon has a typical energy of order quarkonium binding energy. Nevertheless, in the case when the energy carried by the photon is of order typical heavy quark momentum, the multipole expansion doctrine is expected to break down. In this work, we apply the "hard-scattering" approach originally developed to tackle the strongly hindered magnetic dipole ($M1$) transition [Y.~Jia {\it et al.}, Phys. \ Rev. \ D. 82, 014008 (2010)] to the strongly hindered electric dipole ($E1$) transition between heavy quarkonia. We derive the factorization formula for the strongly hindered $E1$ transition rates at the lowest order in velocity and $\alpha_s$ in the context of the non-relativistic QCD (NRQCD), and conduct a detailed numerical comparison with the standard predictions for various bottomonia and charmonia $E1$ transition processes.Comment: 18 pages, 2 figures, 4 table