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Magneto-electro-elastic (MEE) materials are a specific class of advanced smart materials that simultaneously manifest the coupling behavior under electric, magnetic, and mechanical loads. This unique combination of properties allows MEE materials to respond to mechanical, electric, and magnetic stimuli, making them versatile for various applications. This paper investigates the static and time-harmonic field solutions induced by the surface load in a three-dimensional (3D) multilayered transversally isotropic (TI) linear MEE layered solid. Green's functions corresponding to the applied uniform load (in both horizontal and vertical directions) are derived using the Fourier-Bessel series (FBS) system of vector functions. By virtue of this FBS method, two sets of first-order ordinary differential equations (i.e., N-type and LM-type) are obtained, with the expansion coefficients being Love numbers. It is noted that the LM-type system corresponds to the MEE-coupled P-, SV-, and Rayleigh waves, while the N-type corresponds to the purely elastic SH- and Love waves. By applying the continuity conditions across interfaces, the solutions for each layer of the structure (from the bottom to the top) are derived using the dual-variable and position (DVP) method. This method (i.e., DVP) is unconditionally stable when propagating solutions through different layers. Numerical examples illustrate the impact of load types, layering, and frequency on the response of the structure, as well as the accuracy and convergence of the proposed approach. The numerical results are useful in designing smart devices made of MEE solids, which are applicable to engineering fields like renewable energy. [ABSTRACT FROM AUTHOR]

Background: Studies have confirmed that osteoporosis has been considered as one of the complications of diabetes, and the health hazards to patients are more obvious. This study is mainly based on the Taiwan National Health Insurance Database (TNHID). Through the analysis of TNHID, it is shown that the combined treatment of traditional Chinese medicine (TCM) medicine in patients of diabetes with osteoporosis (T2DOP) with lower related risks. Methods: According to the study design, 3131 patients selected from TNHID who received TCM treatment were matched by 1-fold propensity score according to gender, age, and inclusion date as the control group. Cox proportional hazards analyzes were performed to compare fracture surgery, hospitalization, and all-cause mortality during a mean follow-up from 2000 to 2015. Results: A total of 1055/1469/715 subjects (16.85%/23.46%/11.42%) had fracture surgery/inpatient/all-cause mortality of which 433/624/318 (13.83%/19.93%/10.16%) were in the TCM group) and 622/845/397 (19.87%/26.99%/12.68%) in the control group. Cox proportional hazards regression analysis showed that subjects in the TCM group had lower rates of fracture surgery, inpatient and all-cause mortality (adjusted HR = 0.467; 95% CI = 0.225–0.680, P<0.001; adjusted HR = 0.556; 95% CI = 0.330–0.751, P<0.001; adjusted HR = 0.704; 95% CI = 0.476–0.923, P = 0.012). Kaplan-Meier analysis showed that the cumulative risk of fracture surgery, inpatient and all-cause mortality was significantly different between the case and control groups (all log-rank p<0.001). Conclusion: This study provides longitudinal evidence through a cohort study of the value of integrated TCM for T2DOP. More research is needed to fully understand the clinical significance of these results. [ABSTRACT FROM AUTHOR]

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Mathematical modeling of multilayered piezoelectric (PE) ceramic substantially acquires attention due to its distinctive advantages of fast response time, positioning, optical systems, vibration feedback, and sensors, such as deformation and vibration control. As such, fundamental solution of a PE structure is essential. This paper presents three-dimensional (3D) static and dynamic solutions (i.e. Green's functions) in a multilayered transversally isotropic (TI) PE layered half-space. The uniform vertical mechanical load, vertical electrical displacement, and horizontal mechanical load are applied on the surface of the structure. The novel Fourier-Bessel series (FBS) system of vector functions (which is computationally more powerful and streamlined) and the dual-variable and position (DVP) method are employed to solve the related boundary-value problem. Two systems of first-order ordinary differential equations (i.e. the LM- and N-types) are obtained in terms of the FBS system of vector functions, with these expansion coefficients being the Love numbers. A recursive relation for the expansion coefficients is established by using DVP method that facilitates the combination of two neighboring layers into a new one and minimizes the computational effort to a great extent. The corresponding physical-domain solutions are acquired by applying the appropriate boundary/interface conditions. Several numerical examples pertaining to static and dynamic response are solved, and the efficiency and accuracy of the proposed solutions are validated with the existing results for the reduced cases. The solutions provided could be beneficial to better developments of PE materials, configurations, fabrication, and applications in the future. [ABSTRACT FROM AUTHOR]