ABSTRACT
Background and purpose: Diabetes mellitus (DM) is a well-established cardiovascular risk factor for atherosclerotic disease; however, its effect on the risk of rupture of intracranial aneurysms remains controversial. Herein, we aimed to perform a case-control study to investigate the relationship between DM and aneurysmal subarachnoid hemorrhage (aSAH). Methods: We retrospectively reviewed the data of patients with ruptured or unruptured aneurysms who were treated between 2013 and 2023. Univariate and multivariate analyses were performed. Propensity score matching (PSM) analysis was conducted to evaluate the relationship between DM and risk of aSAH. Results: A total of 4,787 patients with 5,768 intracranial aneurysms were included. Among them, 2,957 (61.8%) were females, 1765 (36.9%) had ruptured aneurysms, and 531 (11.1%) presented with DM. Female sex, current drinking, and hypercholesterolemia were associated with a higher risk of aSAH, whereas old age, former smoking, and DM were associated with a lower risk of aSAH in multivariate analysis (p < 0.05). The incidence of DM (13.4%, 406/3022) in the unruptured group was higher than that in the ruptured group (7.1%, 125/1765) (odds ratio, 0.55; 95% confidence interval, 0.444-0.680) (p < 0.001). After propensity score matching, 530 patients with DM were successfully matched, and DM was still associated with a lower risk of aSAH (odds ratio, 0.24; 95% confidence interval, 0.185-0.313) (p < 0.001). Conclusion: Patients with aSAH have a lower incidence of DM, however, this case-cohort study could not establish a causal relationship. A prospective and large study with long-term follow-up is warranted to establish a causal relationship.
ABSTRACT
How to solve the pollution problem of water environment in river network is a hot issue in the world. Artificial floating island is an efficient way to deal with water pollution. Taking Jiashan, Zhejiang, China, as an example, Lattice Boltzmann method (LBM) is used to simulate the law of hydrodynamics and pollutant transport in river network. Lattice Boltzmann equations are established in both artificial floating island and non-artificial floating island sections, and the river network boundary is automatically identified. The simulation results have high accuracy and are more suitable for the establishment of complex boundaries. On this basis, combined with the genetic algorithm (GA) module, the location of the artificial floating island is optimized, and the retention ratio of the pollution in optimized layout of artificial floating island is between and 2.4 and 7.2%. The research results of this paper can provide theoretical reference for the selection and location of artificial floating island in practical engineering.
Subject(s)
Rivers , Water Pollution , Computer Simulation , China , AlgorithmsABSTRACT
Understanding the hydrodynamic behavior of side jets in compound open channels with vegetated floodplain is crucial to jet dilution, sediment transport, and bank stability. Large eddy simulation was used to study horizontal side jets in compound open channels with vegetated floodplain. Predicted mean velocity, turbulent kinetic energy, and secondary currents were compared with experimental data, with a good agreement between measured and calculated data. Analyses of bed shear stress showed that vegetation in the floodplain increases the total drag and decreases bed shear stress, thus governing sediment transport and protecting the bank. The transport mechanism was quantitatively investigated by the quadrant analysis, concentration, and Reynolds flux. The ejection and sweep events were major contributors to the momentum and scalar flux transport. Analyses of concentration and Reynolds flux showed that the secondary flow influenced the spreading of the jet and the location of the concentration peaks, and the distribution of concentration and Reynolds flux did not strictly follow Fickian law in the whole region due to the effect of secondary flow on the concentration distributions. Additionally, the typical vortexes and spatiotemporal evolution of vortex structures in compound open channels, especially those near the junction between the main channel and floodplain, were successfully demonstrated.
