THE PREDICTIVE MODEL OF INTERVAL TIME BASED ON PACING STRATEGY IN A 400 M HURDLES RACE

The purpose of the present study was to verify the reliability of the prediction equation for interval time (the times between hurdles) established from the hierarchical model in the 400 m hurdles. From 155 data samples of previous studies (record range: 47.42–50.99s), regression equations were established to predict each interval time throughout the race (model #1), during the first and latter halves (model #2) and during the first, middle, and last parts (model #3). Leave-one-out cross-validation was used to avoid overtraining for each regression equation. Models #2 and #3 showed better goodness of fit and generalization for each interval time compared to model #1. These hierarchical models are found to be more reliable compared to the non-hierarchical model. The hierarchical model will help to set the pace distribution to achieve the athlete’s target records accurately

HOW HITTING THE HURDLE AFFECTS PERFORMANCE IN THE 110 M HURDLES

This study aimed to clarify the kinematic factors of hurdle hitting and its effect on the performance in 110-m Hurdles. Three male hurdlers volunteered. The trial which from start to the second hurdle was conducted about 20 times and these trials were recorded by motion capture system with 240 Hz. From all trials, 19 Non-Hitting Trials (NHT) and 33 Hitting Trials (HT) were classified. Kinematic variables and hitting grade, which is a value obtained by root mean square of the acceleration of hurdle’s bar, were calculated. As a result, the cause of hitting the hurdle was the low height of centre of mass (CoM) of the body at the take-off. Moreover, hitting grade was correlated with decrease in velocity by hurdle hitting during the hurdle clearance phase (r = 0.43). Furthermore, a decrease in running speed after landing at the first hurdle was also confirmed in HT trials

Effect of Dy substitution in the giant magnetocaloric properties of HoB2_{2}

Recently, a massive magnetocaloric effect near the liquefaction temperature of hydrogen has been reported in the ferromagnetic material HoB$_{2}$. Here we investigate the effects of Dy substitution in the magnetocaloric properties of Ho$_{1-x}$Dy$_{x}$B$_{2}$ alloys ($\textit{x}$ = 0, 0.3, 0.5, 0.7, 1.0). We find that the Curie temperature ($\textit{T}$$_{C}$) gradually increases upon Dy substitution, while the magnitude of the magnetic entropy change |$\Delta \textit{S}_{M}$| at $\textit{T}$ = $\textit{T}_{C}$ decreases from 0.35 to 0.15 J cm$^{-3}$ K$^{-1}$ for a field change of 5 T. Due to the presence of two magnetic transitions in these alloys, despite the change in the peak magnitude of |$\Delta \textit{S}_{M}$|, the refrigerant capacity ($\textit{RC}$) and refrigerant cooling power ($\textit{RCP}$) remains almost constant in all doping range, which as large as 5.5 J cm$^{-3}$ and 7.0 J cm$^{-3}$ for a field change of 5 T. These results imply that this series of alloys could be an exciting candidate for magnetic refrigeration in the temperature range between 10-50 K.Comment: 19 pages, 5 figures, 2 table

Chirality-selected crystal growth and spin polarization over centimeters of transition metal disilicide crystals

We performed a chirality-controlled crystal growth of transition metal disilicide NbSi$_{2}$ and TaSi$_{2}$ by using a laser-diode-heated floating zone (LDFZ) method. The crystal chirality was evaluated in the crystals of centimeters in length by performing single crystal X-ray diffraction as well as probing a spin polarization originating from chirality-induced spin selectivity (CISS) effect. The crystals of right-handed NbSi$_{2}$ and of left-handed TaSi$_{2}$ were obtained in the conventional LDFZ crystal growth, while the left-handed NbSi$_{2}$ and right-handed TaSi$_{2}$ crystals were grown by the LDFZ method with the composition-gradient feed rods. The spin polarization via the CISS was observed over centimeters in the NbSi$_{2}$ single crystals and the sign of the CISS signals was dependent on the chirality of crystals. The correlation between the crystal chirality and CISS signals indicates that the CISS measurements work as a non-destructive method for chirality determination even in centimeter-long specimens.Comment: 9 pages, 6 figure

Anionic ordering in Pb₂Ti₄O₉F₂ revisited by nuclear magnetic resonance and density functional theory

複合アニオン材料の構造決定における実験と計算の融合的アプローチ. 京都大学プレスリリース. 2022-10-31.A combination of 19F magic angle spinning (MAS) nuclear magnetic resonance (NMR) and density functional theory (DFT) were used to study the ordering of F atoms in Pb₂Ti₄O₉F₂. This analysis revealed that F atoms predominantly occupy two of the six available inequivalent sites in a ratio of 73 : 27. DFT-based calculations explained the preference of F occupation on these sites and quantitatively reproduced the experimental occupation ratio, independent of the choice of functional. We concluded that the Pb atom's 6s2 lone pair may play a role (∼0.1 eV per f.u.) in determining the majority and minority F occupation sites with partial density of states and crystal orbital Hamiltonian population analyses applied to the DFT wave functions

Anionic ordering in Pb₂Ti₄O₉F₂ revisited by nuclear magnetic resonance and density functional theory

複合アニオン材料の構造決定における実験と計算の融合的アプローチ. 京都大学プレスリリース. 2022-10-31.A combination of 19F magic angle spinning (MAS) nuclear magnetic resonance (NMR) and density functional theory (DFT) were used to study the ordering of F atoms in Pb₂Ti₄O₉F₂. This analysis revealed that F atoms predominantly occupy two of the six available inequivalent sites in a ratio of 73 : 27. DFT-based calculations explained the preference of F occupation on these sites and quantitatively reproduced the experimental occupation ratio, independent of the choice of functional. We concluded that the Pb atom's 6s2 lone pair may play a role (∼0.1 eV per f.u.) in determining the majority and minority F occupation sites with partial density of states and crystal orbital Hamiltonian population analyses applied to the DFT wave functions

Structures of the wild-type MexAB–OprM tripartite pump reveal its complex formation and drug efflux mechanism

In Pseudomonas aeruginosa, MexAB–OprM plays a central role in multidrug resistance by ejecting various drug compounds, which is one of the causes of serious nosocomial infections. Although the structures of the components of MexAB–OprM have been solved individually by X-ray crystallography, no structural information for fully assembled pumps from P. aeruginosa were previously available. In this study, we present the structure of wild-type MexAB–OprM in the presence or absence of drugs at near-atomic resolution. The structure reveals that OprM does not interact with MexB directly, and that it opens its periplasmic gate by forming a complex. Furthermore, we confirm the residues essential for complex formation and observed a movement of the drug entrance gate. Based on these results, we propose mechanisms for complex formation and drug efflux