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In this study, under the conformity of engineering reality, considering the influence of slip coefficient on the variation range of winding angle, 15 composite lay‐up schemes of hydrogen storage vessels were designed using grid theory, and the hydrogen storage vessels's structural strength was analyzed. The distribution of non‐geodesic fiber windings on the outer surface of the inner layer was solved using differential theory and the winding principle, and ABAQUS established the finite element model. The maximum stress value and stress distribution of the composite layer of the hydrogen storage vessel along the fiber direction were studied, the damage of the composite layer was analyzed, and the pressure and mode of the bursting were predicted. Results show that the structural strength of the hydrogen storage vessel designed by this method can be effectively guaranteed. The hoop winding layer bears the majority of the stress on the hydrogen storage vessel, while the helical winding layer's fiber strength is not entirely utilized. The hydrogen storage vessel gains greater structural strength when the circumferential winding layer is concentrated and situated at the outermost portion of the composite layer. The layup scheme has an impact of approximately 17.21% on burst pressure. Highlights: Effect of slip coefficient on the change of winding angle.Different forms of composite lay‐up schemes were designed.The stress distribution in the composite layer was studied.Analyzed structural strength and damage of the composite layer.Predicted the pressure and mode of bursting. [ABSTRACT FROM AUTHOR]

Introduction: White matter hyperintensities (WMH) are commonly associated with balance and gait disturbances. Little is known whether WMH may affect post-stroke balance and gait recovery. We aim to investigate the association of post-stroke balance and gait recovery with imaging marker of WMH on magnetic resonance imaging (MRI). Methods: This prospective cohort study will enroll consecutive patients with first-ever ischemic hemisphere stroke, between September 2023 and December 2024. Clinical data will be collected on day 30 ± 3 and at 3 months after stroke onset. WMH on FLAIR are graded according to the modified Fazekas scale. Resting-state functional MRI (rs-fMRI) and diffusion tensor imaging (DTI) will be acquired to evaluate functional and structural connectivity. The primary endpoint is balance recovery, defined as a Postural Assessment Scale for Stroke score of 32 or higher at 3 months. The secondary endpoint is gait recovery, assessed using the modified Fugl-Meyer Gait Assessment at 3 months. We will investigate the association of post-stroke balance and gait recovery with WMH severity as well as WMH-related functional and structural connectivity. Conclusion: The study may contribute to clarify the effect of WMH on post-stroke balance and gait disorder recovery. [ABSTRACT FROM AUTHOR]

Background: Patients with cardiovascular comorbidities are at high risk of poor outcome from COVID-19. However, how the burden (number) of vascular risk factors influences the risk of severe COVID-19 disease remains unresolved. Our aim was to investigate the association of severe COVID-19 illness with vascular risk factor burden.Methods: We included 164 (61.8 ± 13.6 years) patients with COVID-19 in this retrospective study. We compared the difference in clinical characteristics, laboratory findings and chest computed tomography (CT) findings between patients with severe and non-severe COVID-19 illness. We evaluated the association between the number of vascular risk factors and the development of severe COVID-19 disease, using a Cox regression model.Results: Sixteen (9.8%) patients had no vascular risk factors; 38 (23.2%) had 1; 58 (35.4%) had 2; 34 (20.7%) had 3; and 18 (10.9%) had ≥4 risk factors. Twenty-nine patients (17.7%) experienced severe COVID-19 disease with a median (14 [7-27] days) duration between onset to developing severe COVID-19 disease, an event rate of 4.47 per 1000-patient days (95%CI 3.10-6.43). Kaplan-Meier curves showed a gradual increase in the risk of severe COVID-19 illness (log-rank P < 0.001) stratified by the number of vascular risk factors. After adjustment for age, sex, and comorbidities as potential confounders, vascular risk factor burden remained associated with an increasing risk of severe COVID-19 illness.Conclusions: Patients with increasing vascular risk factor burden have an increasing risk of severe COVID-19 disease, and this population might benefit from specific COVID-19 prevention (e.g., self-isolation) and early hospital treatment measures. [ABSTRACT FROM AUTHOR]