| 1 | Research on emergency rescue technology and equipment for train operation accidents on a heavy-haul railway network显示文摘Bridges,tunnels,cuttings and high subgrade account for a relatively large proportion in China’s heavy-haul railway system,where 10000 t of unit trains and 20000 t of combined trains are in operation.When a train operation accident occurs,it can easily cause vehicle intrusions,slant-span lines,tipping and stacking.Based on the viewpoint of system engineering,rescue methods such as hoisting,lifting,pulling and overturning are integrated,according to the characteristics of heavy-haul transport and the construction practice of train accident rescue system.A scheme of technical research and equipment configuration relating to heavy-haul railway rescue in China is put forward based on the situation—embankment,bridge,tunnel(including cuttings),ramp and curve rescue,and so on—and three-dimensional finite-element modelling and calculation checks on the key components are carried out. | Xianping Zhou Xiang Wei Lin Ma Fuwei Bai Hongwei Huang | 2020 | Transportation Safety and Environment2020，2，4： | 0 |
| 2 | Isotope effect on the Casimir force显示文摘Isotopic dependence of the Casimir force is key to probing new physics and pushing novel technologies at the micro and nanoscale, but is largely unexplored. In 2002, an isotope effect of 10^(-4) was estimated for metals—orders of magnitude beyond the experimental resolution. Here, by employing the Lifshitz theory, we reveal a significant isotope effect of over 10^(-1) for polar dielectrics. This effect arises from the isotope-mass-induced line shift of the zone-center optical phonons and is insensitive to the linewidth. We perform numerical analyses on both the imaginary and real-frequency axes, and derive analytical formulas for predicting the isotope effect. The three-orders-of-magnitude difference between polar dielectrics and metals arises from the distinct isotopic dependence of the phonon and plasma frequencies. Our work opens up a new avenue for engineering forces at small scales and may also facilitate the quest for the fifth force of nature. | Lanyi Xie Fuwei Yang Bai Song | 2023 | Science China(Physics,Mechanics & Astronomy)2023，66，10： | 0 |
| 3 | Discharge heart rate and 1-year clinical outcomes in heart failure patients with atrial fibrillation显示文摘Background: The association between heart rate and 1-year clinical outcomes in heart failure (HF) patients with atrial fibrillation (AF), and whether this association depends on left ventricular ejection fraction (LVEF), are unclear. We investigated the relationship between discharge heart rate and 1-year clinical outcomes after discharge among hospitalized HF patients with AF, and further explored this association that differ by LVEF level.Methods: In this analysis, we enrolled 1760 hospitalized HF patients with AF from the China Patient-centered Evaluative Assessment of Cardiac Events Prospective Heart Failure study from August 2016 to May 2018. Patients were categorized into three groups with low (<65 beats per minute [bpm]), moderate (65-85 bpm), and high (≥86 bpm) heart rate measured at discharge.Cox proportional hazard models were employed to explore the association between heart rate and 1-year primary outcome, which was defined as a composite outcome of all-cause death and HF rehospitalization.Results: Among 1760 patients, 723 (41.1%) were women, the median age was 69 (interquartile range [IQR]: 60-77) years, median discharge heart rate was 75 (IQR: 69-84) bpm, and 934 (53.1%) had an LVEF <50%. During 1-year follow-up, a total of 792 (45.0%) individuals died or had at least one HF hospitalization. After adjusting for demographic characteristics, smoking status, medical history, anthropometric characteristics, and medications used at discharge, the groups with low (hazard ratio [HR]: 1.32, 95% confidence interval [CI]: 1.05-1.68,P = 0.020) and high (HR: 1.34, 95% CI: 1.07-1.67,P = 0.009) heart rate were associated with a higher risk of 1-year primary outcome compared with the moderate group. A significant interaction between discharge heart rate and LVEF for the primary outcome was observed (P for interaction was 0.045). Among the patients with LVEF ≥50%, only those with high heart rate were associated with a higher risk of primary outcome compared with the group with moderate heart rate (HR: 1.38, 95% CI: 1.01-1.89,P = 0.046), whereas there was no difference between the groups with low and moderate heart rate. Among the patients with LVEF <50%, only those with low heart rate were associated with a higher risk of primary outcome compared with the group with moderate heart rate (HR: 1.46, 95% CI: 1.09-1.96,P = 0.012), whereas there was no difference between the groups with high and moderate heart rate.Conclusions: Among the overall HF patients with AF, both low (<65 bpm) and high (≥86 bpm) heart rates were associated with poorer outcomes as compared with moderate (65-85 bpm) heart rate. Among patients with LVEF ≥50%, only a high heart rate was associated with higher risk;while among those with LVEF <50%, only a low heart rate was associated with higher risk as compared with the group with moderate heart rate.Trail Registration: Clinicaltrials.gov;NCT02878811. | Fuwei Xing Xin Zheng Lihua Zhang Shuang Hu Xueke Bai Danli Hu Bing Li Jing Li | 2022 | Chinese Medical Journal2022，，1： | 0 |
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