Three-dimensional printing (3Dp) is being increasingly used in medical education. Although the use of such lifelike models is beneficial, well-powered, randomized studies supporting this statement are scarce. Two spinal fracture simulation models were generated by 3Dp. Altogether, 120 medical students (54.2% females) were randomized into three teaching module groups [two-dimensional computed tomography images (CT), 3D, or 3Dp] and asked to answer 10 key anatomical and 4 evaluative questions. Students in the 3Dp or 3D group performed significantly better than those in the CT group, although males in the 3D group scored higher than females. Students in the 3Dp group were the first to answer all questions, and there were no sex-related differences. Pleasure, assistance, effect, and confidence were more predominant in students in the 3Dp group than in those in the 3D and CT groups. This randomized study revealed that the 3Dp model markedly improved the identification of complex spinal fracture anatomy by medical students and was equally appreciated and comprehended by both sexes. Therefore, the lifelike fracture model made by 3Dp technology should be used as a means of premedical education.

Summary Based on the consolidation theory raised by Fredlund, the solutions for the equal‐strain consolidation of unsaturated foundation with the prefabricated vertical drain considering smear effect and drain resistance are analytically formulated in this paper. Firstly, governing equations for excess pore pressures (i.e., excess pore‐air and pore‐water pressures) under the equal‐strain hypothesis are derived with the introduction of radial boundary conditions. Afterwards, the obtained coupled equations are solved by applying general integration, decoupling process, and Fourier sine series expansion. The smear coefficients and factors of drain resistance corresponding to air and water phases are both captured explicitly in the final solutions. Furthermore, the degenerated solutions are employed to verify the reliability of the current solutions. Finally, a parametric study is conducted to study the consolidation characteristics of the proposed foundation model against modeling sizes (S and N), smear coefficients (αa and αw), and drain resistance factors (Ga and Gw).

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Developing an analytical solution for the consolidation of unsaturated soils remains a challenging task due to the complexity of coupled governing equations for air and water phases. This paper presents an equal-strain model for the radial consolidation of unsaturated soils by vertical drains, and the effect of drain resistance is also considered. Simplified governing equations are established, and an analytical solution to calculate the excess pore-air and pore-water pressures is derived by using the methods of matrix analysis and eigenfunction expansion. The average degrees of consolidation for air and water phases and the ground surface settlement are also given. The solutions of the equal-strain model are verified by comparing the proposed free-strain model with the equal-strain model, and reasonably good agreement is obtained. Moreover, parametric studies regarding the drain resistance effect are graphically presented.

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Objective: To explore the preliminary application of three-dimensional (3D) printing technique in preoperative localization of meningiomas in primary hospitals. Patients and Methods: The enrolled subjects were 13 patients in the