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Aiming at the existing heavy-haul railway, bridges hardly meet the transportation requirements. Based on the spatial vibration calculation model of the freight train–track–bridge (FTTB) system, the FTTB spatial vibration model under the condition of auxiliary steel beam reinforcement is established. Besides, according to the random analysis method of train derailment energy, coming up with an evaluation method of auxiliary steel beam reinforcement is based on safety and dynamic response, which is used to discuss the train safety and the change law of FTTB system vibration response. The results show that the derailment resistance of the FTTB system is increased by 22.6% after the auxiliary steel beam is reinforced. Compared with the previous speed (115.56 km/h), the speed is 132.73 km/h after the auxiliary steel beam reinforcement; at the same time, the allowable limit speed increases from 92.49 km/h to 106.18 km/h. In addition, the reinforcement of the auxiliary steel beam can not only effectively reduce the lateral vibration response of the FTTB system under the action of empty wagon but also effectively decline the vertical vibration response of the FTTB system under the action of the loaded wagon, which can meet the stability requirement for running at the speed of 90 km/h. In summary, the reinforcement of auxiliary steel beams can improve the running safety of trains, reduce the vibration response of the FTTB system, and meet the requirements of operation stability.

Abstract Background The combined effects of anticancer drugs with nutritional factors against tumor cells have been reported previously. This study characterized the efficacy and possible mechanisms of the combination of sorafenib and vitamin K1 (VK1) on glioma cell lines. Methods We examined the effects of sorafenib, VK1 or their combination on the proliferation and apoptosis of human malignant glioma cell lines (BT325 and U251) by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, flow cytometry and 4′,6-diamidino-2-phenylindole (DAPI) assay. The signaling pathway changes were detected by western blotting. Results Sorafenib, as a single agent, showed antitumor activity in a dose-dependent manner in glioma cells, but the effects were more pronounced when used in combination with VK1 treatment. Sorafenib in combination with VK1 treatment produced marked potentiation of growth inhibition and apoptosis, and reduced expression of phospho-mitogen-activated protein kinase kinase (MEK) and phospho-extracellular signal-regulated kinase (ERK). Furthermore, the expression levels of antiapoptotic proteins Bcl-2 and Mcl-1 were significantly reduced. Conclusions Our findings indicated that VK1 enhanced the cytotoxicity effect of sorafenib through inhibiting the Raf/MEK/ERK signaling pathway in glioma cells, and suggested that sorafenib in combination with VK1 maybe a new therapeutic option for patients with gliomas.

To study the impact of upwarp deformation in the ballastless track on the jumping behavior of the high-speed vehicle, utilizing UM and ANSYS joint simulation, a vertical vibration model of high-speed vehicle on CRTS II slab ballastless track was developed based on the non-Hertz wheel–rail contact model of virtual penetration theory. By using the single-wave cosine curve simulating the characteristics of upwarp deformation in the track slab, we calculated the whole process of wheel jumping. This allowed us to analyze how the amplitude and wavelength of the track slab upward deformation influence the vibration response of the vehicle–track system. Our findings indicate that when a wheel passes through the arch section of the track slab, the entire wheel jumping process consists of distinct stages: "wheel–rail bonding, wheel–rail separation, wheel–rail impact (one or more times), and wheel–rail bonding." As the amplitude of upwarp deformation increases and the wavelength decreases, significant changes occur in several parameters, including the vertical force between the wheel and rail, wheel unloading rate, wheel jump height, frequency, duration, and vertical displacement of the rail. Additionally, when the wavelength is between 2 and 6 m and the amplitude is 8 mm, the vertical force between the wheel and rail becomes zero, the wheel load reduction rate is one, and the wheel jumps. When the wavelength is less than 3 m, the wheel jump height exceeds the flange height, increasing the risk of derailment. Meanwhile, during the first wheel–rail impact, the wheel–rail vertical force and the rail vertical displacement reach their maximum, potentially impacting rail service performance negatively. Finally, compared to the amplitude of the track slab camber deformation, its wavelength has a greater impact on the entire process of wheel jumping. It is recommended that attention be paid to the change in the wavelength of the track slab camber during the maintenance and repair of the ballastless track. [ABSTRACT FROM AUTHOR]

Background: There is a gap between the principles of person-centred dementia care and their actual implementation. However, scoping reviews of the barriers and facilitators to implementing person-centred dementia care in long-term care facilities for Western countries and Asian countries are lacking. Objective: To identify and compare the barriers and facilitators to implementing person-centred dementia care in long-term care facilities between Western and Asian countries. Methods: In line with Arksey and O'Malley's methodology, a scoping review was conducted and is reported following PRISMA-ScR guidelines. Nine English language databases and three Chinese databases were searched to identify qualitative and quantitative research studies published in English and Chinese. Thematic analysis was used to summarise and characterize the barriers and facilitators to implementing person-centred dementia care in long-term care facilities for Western and Asian countries. Results: Thirty-three studies were included. Over half were conducted in Western countries (n =20). Barriers and facilitators were grouped under four high level themes: Nursing and care staff factors, people living with dementia and family factors, organizational factors, and resource factors. Inadequate knowledge of person-centred care, staffing shortages, time constraints, and low wages were the principal barriers to implementing person-centred dementia care in both Western and Asian countries. Conclusions: The findings indicate that staff encounter numerous obstacles and needs in implementing person-centred care for people living with dementia in long-term care settings. Educational levels of nursing staff in Western countries were generally higher compared to Asian countries. Additionally, work-related injuries and stigma associated with dementia care presented unique challenges for nursing staff in Asia and were not cited in Western studies. Conversely, family-related factors were more frequently and elaborately cited as influencing person-centred dementia care in Western long-term care facilities. Moreover, Asian studies identified a significant lack of educational training support for person-centred dementia care, as well as shortages in staffing and poor availability of personalized, home-like environments [ABSTRACT FROM AUTHOR]