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A convenient but efficient tool for evaluating dietary intakes in Chinese professional athletes has yet to be established. The aim of this study was to assess the validity of a short semi-quantitative food frequency questionnaire (FFQ) through comparison with 3-day weighed food records (3DWFRs) and corresponding serum biomarkers from a cohort of 102 professional athletes, while also evaluating its reproducibility. The relative validity was assessed using Spearman correlation coefficients, cross-quintiles classification, weighted kappa, and Bland–Altman analysis, while reproducibility was evaluated using the Spearman correlation coefficients and intraclass correlation coefficient (ICC) between two FFQs. The results showed the median (range) crude correlation coefficients (CCs) between the first FFQ and 3DWFRs for energy and nutrients, and the food groups were 0.331 (0.219 to 0.568) and 0.292 (-0.035 to 0.455), respectively. Omega-3 polyunsaturated fatty acid (EPA, DHA, and EPA+DHA) intake estimated from the FFQ significantly correlated with corresponding serum biomarkers, with CCs ranging from 0.389 to 0.520. Weighted kappa statistics, indicating acceptable consistency (> 0.2) for most items, varied from -0.076 to 0.581, except for vitamin C, vegetables, and oils. Misclassification of nutrients and food groups into extreme quartiles was rare, with a median misclassification rate of 2% (ranging from 1% to 12%) and 3% (ranging 0 to 10%), respectively. Bland–Altman analysis revealed good agreement between FFQ and 3DWFRs, with over 90% of data points falling within the limits of agreement (LOA) for all assessed nutrients and food groups. In the reproducibility analysis, the median (range) crude CC and ICC for energy and nutrients were 0.574 (0.423 to 0.643) and 0.668 (0.558 to 0.763), respectively, while for food groups, they were 0.681 (0.242 to 0.764) and 0.640 (0.371 to 0.787), respectively. In conclusion, the short FFQ demonstrated acceptable relative validity and reproducibility for most nutrients and food groups, suggesting its potential as a valuable tool for assessing dietary intake and nutrition status among young Chinese athletes. [ABSTRACT FROM AUTHOR]

Rechargeable aqueous zinc‐ion batteries (AZIBs) are one of the most promising post‐lithium battery technologies due to their low cost, high safety, and environmental friendliness. However, their practical development is hindered by the issues of Zn metal anodes, including dendrite growth, passivation, hydrogen evolution and other side reactions. Herein, to circumvent these issues, a facile and universal alloy electrodeposition strategy is proposed to construct a 3D structured ternary Zn alloy artificial interphase layer on Zn foil as an anode for high‐performance AZIBs. The density functional theory (DFT) theoretical calculations, in situ optical visualization and spectroscopic results validate that the zincophilic Zn─Sn─Bi@Zn ternary alloy anode with lower migration energy barrier and weak hydrogen adsorption sites can promote the uniform Zn deposition and suppress hydrogen evolution reactions. The Zn─Sn─Bi@Zn//NH4V4O10 full cell demonstrates a high specific capacity 110.4 mAh g−1 even after 10 000 cycles at 5.0 A g−1. Notably, the full cell with a high NH4V4O10 cathode loading mass of ≈20.0 mg cm−2 maintains cyclic stability for 400 cycles. This work proposes an innovative Zn‐based ternary alloy anode methodology as a design strategy for advanced AZIBs and beyond. [ABSTRACT FROM AUTHOR]

Lithium iron phosphate (LiFePO4, LFP), an olivine–type cathode material, represents a highly suitable cathode option for lithium–ion batteries that is widely applied in electric vehicles and renewable energy storage systems. This work employed the ball milling technique to synthesize LiFePO4/carbon (LFP/C) composites and investigated the effects of various doping elements, including F, Mn, Nb, and Mg, on the electrochemical behavior of LFP/C composite cathodes. Our comprehensive work indicates that optimized F doping could improve the discharge capacity of the LFP/C composites at high rates, achieving 113.7 mAh g−1 at 10 C. Rational Nb doping boosted the cycling stability and improved the capacity retention rate (above 96.1% after 100 cycles at 0.2 C). The designed Mn doping escalated the discharge capacity of the LFP/C composite under a low temperature of −15 °C (101.2 mAh g−1 at 0.2 C). By optimizing the doping elements and levels, the role of doping as a modification method on the diverse properties of LFP/C cathode materials was effectively explored. [ABSTRACT FROM AUTHOR]

Inorganic components in the solid electrolyte interphases (SEIs) on lithium (Li) metal play a critical role in Li metal batteries (LMBs) since the presence of numerous inorganic constituents may promote ion diffusion and mechanical strength. However, manipulating inorganic components and acquiring an in-depth understanding of their roles in LMBs remain challenging. Herein, we deliberately introduce different kinds of inorganic components (e.g., LiF, Li3N, and their complexes) into SEIs on Li metal in LMBs by electrolyte engineering. Through in situ atomic force microscopy and electrochemical experiments, the roles of the specific inorganic component in SEIs played in the process of Li nucleation and evolution are revealed, and the detailed synergistic effect of LiF and Li3N is clarified. We demonstrate that the simultaneous presence of LiF and Li3N in SEIs enables homogeneous and dense lithium metal nucleation and growth, improving both the chemical stability and mechanical strength of SEIs for highly stable LMBs. In contrast, individual LiF and Li3N in SEIs induce needle morphology of Li metal and discrete Li deposition, respectively. These findings can provide rational guidelines for optimizing SEIs through electrolyte engineering for stable LMBs. [ABSTRACT FROM AUTHOR]

A gearbox which is developed independently and used for 200 km/h passenger locomotive is introduced. The analysis of gear and box is carried out respectively by the CAD and finite element analysis,and the high reliability of the gearbox is confirmed. The gear blanks are forged from 18 CrNiMo7-6 alloy steel which is electroslag remelted. In order to ensure the reliability and smoothness during the gear meshing,the carburizing,quenching,shot peening and profile correction are added in the process of gear forming. The material of the gearbox is adopted aluminum alloy instead of the ductile iron,not only meet the requirements of lightweight design,but also contribute to the cooling of the gearbox. During the type test,the gear box running smoothly,the temperature rise of the bearings is also meeting the requirement.

Taking designed labyrinth seal of a high speed EMU gearbox as the research object. The numerical simulation of the internal flow field of labyrinth seal is carried out by using the Fluent software,the pressure,speed,velocity vector and turbulence distribution cloud of the internal flow field of the labyrinth seal are obtained. The sealing mechanism and process of the gearbox labyrinth seal is analyzed. The results show that the fluid flows through the sealing gap when the pressure is reduced,the pressure is reduced very little.When the fluid flows out of the sealing gap into the cavity is the pressure equalizing process. After entering the cavity,the turbulivity of the cavity is the largest and the pressure is the smallest. As the distance from the center of the cavity increases,the speed increases and the pressure increases. The distribution characteristics of the flow field in the labyrinth seal under different pressure ratios are analyzed,which indicated that the leakage increases with the increase of the inlet/outlet pressure ratio,and the pressure ratio is not linearly related to the leakage. The simulation results can be used as reference for the design of gearbox labyrinth seal.

The dynamic numerical simulation of inner oil bath lubrication flow filed of a type locomotive gearbox is carried out by using dynamic mesh and Profile technology based on CFD software Fluent. A two- dimensional VOF multiphase model of the gearbox is built,the dynamic characteristic of the inner flow filed is calculated as the input velocity of the gearbox varied during the 3 speed（ starting at low speed,medium speed,maximum speed）. The phase,pressure and velocity distribution of internal flow field of the gearbox under different speed condition are obtained. The simulation results would provide a theoretical basis for the design and maintenance of the gearbox.

Taking a high- speed motor train unit transmission gear system as an example,by using gear analysis software KISSsoft,the deformation of gear supporting axial in the transmission process is calculated.Through the method of modification to compensate the influence of the shaft deformation on the gear meshing performance. Then,the difference between before and after the modification of gear meshing contact spot,tooth surface line load distribution and the transmission error,etc are compared to ensure the motor train unit gear transmission system working more stable and reliable. The work of the research has important reference value to the design of the motor train unit gear pair.

Due to the current situation of Chinese high-speed motor train unit（EMU） gearbox monopolized by foreign for a long time,and facing the gearbox body cracking problems frequently,the aluminum alloy box body of high-speed EMU is redesigned.By using the three-dimensional modeling software Solid Works,the box body model is created,and the load calculation of the designed box body under two conditions of short circuit and startup is carried out separately.By using the finite element analysis software Workbench,the strength is analyzed,then the simulation test results verify the designed box body won’t appear plastic deformation and crack in both working conditions.According to the analysis results evaluated by TJ / JW064-2015 in startup conditions,to testify that the designed housing meet the requirement of train operation.The research has important reference value to the independent research and development of the high speed Emu gearbox.

Taking the QT400-18 L low temperature ductile iron gear box used for locomotive as example,through the control of the element content of the material,the graphite spheroidization is more fully. At the same time,the samples are heat treated to ensure the stability of mechanical property. In the casting process,the casting process is improved to reduce the casting defects and to ensure the surface quality of the products.

Omega‐3 polyunsaturated fatty acids (omega‐3 PUFAs) are essential for improving the health and performance of athletes. The present study aimed to evaluate the nutritional status of omega‐3 PUFAs in Chinese elite athletes by both dietary intake analysis and serum biomarker detection. A cross‐sectional analysis of data from 54 elite athletes (24 men and 30 women) from Shanghai professional sports teams was conducted. A food frequency questionnaire (FFQ) was employed to analyze dietary intake, and gas chromatography–mass spectrometry (GC–MS/MS) was conducted to measure serum biomarkers of PUFAs. Correlation analysis was performed to investigate the relationships of PUFA biomarkers with diet, inflammation and oxidative stress. The results showed that the median intake of EPA + DHA among athletes was 132 mg/d, which is lower than the minimum value recommended by dietary guidelines (250 mg/d). The average serum EPA + DHA was 4.0 ± 1.1%, and the ratio of omega‐6/omega‐3 was 7.7 ± 1.7. Most (96.3%) of the athletes were below the targeted value of serum EPA + DHA, which is associated with a reduction in cardiovascular risk. Correlation analysis showed that the serum EPA + DHA was positively correlated with the long‐term dietary intake of EPA + DHA and negatively correlated with inflammatory markers. In conclusion, the serum circulating EPA + DHA and omega‐6/omega‐3 ratio are effective biomarkers reflecting the nutritional status of PUFAs in athletes. Omega‐3 PUFAs have a potential effect on inhibiting inflammatory markers. Hence, it is necessary for Chinese athletes to improve their suboptimal nutritional status of PUFAs through dietary intervention. [ABSTRACT FROM AUTHOR]

Introduction: Protein-bound uraemic toxins (PBUTs) are poorly removed by conventional dialytic techniques, given their high plasma protein binding, and thus low, free (dialysable) plasma concentration. Here, we evaluated and compared PBUTs removal among conventional haemodialysis (HD), adsorption-based HD, displacement-based HD, and their 2 combinations both in vitro and in vivo. Methods: The removal of PBUTs, including 3-carboxy-4-methyl-5-propyl-2-furan-propanoic acid (CMPF), p-cresyl sulphate (PCS), indoxyl sulphate (IS), indole-3-acetic acid (3-IAA), and hippuric acid, was first evaluated in an in vitro single-pass HD model. Adsorption consisted of adding 40 g/L bovine serum albumin (Alb) to the dialysate and displacement involved infusing fatty acid (FA) mixtures predialyser. Then, uraemic rats were treated with either conventional HD, Alb-based HD, lipid emulsion infusion-based HD or their combination to calculate the reduction ratio (RR), and the total solute removal (TSR) of solutes after 4 h of therapy. Results: In vitro dialysis revealed that FAs infusion prefilter increased the removal of PCS, IS, and 3-IAA 3.23-fold, 3.01-fold, and 2.24-fold, respectively, compared with baseline and increased the fractional removal of CMPF from undetectable at baseline to 14.33 ± 0.24%, with a dialysis efficacy markedly superior to Alb dialysis. In vivo dialysis showed that ω-6 soybean oil-based lipid emulsion administration resulted in higher RRs and more TSRs for PCS, IS, and 3-IAA after 4-h HD than the control, and the corresponding TSR values for PCS and IS were also significantly increased compared to that of Alb dialysis. Finally, the highest dialysis efficacy for highly bound solute removal was always observed with their combination both in vitro and in vivo. Conclusions: The concept of combined displacement- and adsorption-based dialysis may open up new avenues and possibilities in the field of dialysis to further enhance PBUTs removal in end-stage renal disease. [ABSTRACT FROM AUTHOR]