Bismuth layer-structured ferroelectrics (BLSFs) have become the preferred high-temperature piezoelectric ceramics due to their elevated Curie temperature (T_C) and environmental friendliness. Bi₄Ti₃O₁₂ (BIT) exhibits a remarkable T_C of 675 °C, demonstrating promising potential for high-temperature device applications. However, oxygen vacancies generated during sintering degrade piezoelectric activity. To address this limitation, an A/B-site co-doping strategy was employed to reduce oxygen vacancy concentration and enhance comprehensive electrical properties. Results reveal that introducing A-site substituents with ionic radii comparable to Bi³⁺ based on non-equivalent B-site doping simultaneously improves piezoelectric performance while maintaining high T_C.

Background: Blunt chest injuries are the predominant cause of rib fractures, which frequently result in pulmonary complications. We hypothesized that different trauma mechanisms and fracture patterns are associated with pulmonary complications in elderly patients (≥65 years) with isolated rib fractures.

Methods: We retrospectively reviewed the data of patients with rib fractures recorded in the electronic medical record system of a trauma center from 2015 to 2019. The correlation between age, comorbidities, trauma mechanisms, fracture patterns, and pulmonary complications was examined.

Results: A total of 168 elderly patients with isolated rib fractures after trauma were included in the study. Except for one patient who died, all other patients recovered and were discharged. Univariate analysis identified age, trauma mechanisms, and fracture patterns as potential risk factors for pulmonary complications. Multivariate logistic regression analysis found that falls [odds ratio (OR) 5.051, 95% confidence interval (CI): 1.380–18.485; P=0.01], rib fracture displacement (OR 4.924, 95% CI: 1.826–13.275; P=0.002), and multiple rib fractures (≥2 ribs) (OR 2.984, 95% CI: 1.182–7.531; P=0.02) were the independent risk factors for pulmonary complications. Subgroup analysis showed that hemothorax occurred in 47 (85.5%, P=0.001) patients with falls, 69 (89.6%, P<0.001) patients with displaced rib fractures, and 99 (74.4%, P<0.001) patients with multiple rib fractures.

Conclusions: The traumatic mechanisms and fracture patterns appear to be related to pulmonary complications, with patients experiencing falls, displaced rib fractures, and multiple rib fractures being more likely to develop these complications.

Keywords: Mechanisms; pulmonary complications; isolated rib fractures; elderly