To prepare high-permittivity composite materials for dielectrically functional gradient materials (d-FGMs) by the stereolithographic 3D-printing technique, three ceramic powders (i.e., alumina, barium titanate, and strontium titanate) are selected as functional fillers for a UV-curable resin matrix. The viscosity and UV curing depth of the uncured slurry are tested for feasibility of 3D printing. Comprehensive electrical properties, including volume resistivity, permittivity, dielectric loss, and breakdown strength of the cured composites are measured. The effects of the filler types, morphologies, particle sizes, and volume fractions on the UV curing characteristics of the slurry and dielectric properties of cured composites are systematically analyzed. The experimental results show that spherical fillers with large particle sizes, smooth surfaces, and high permittivity are conducive for reducing the slurry viscosity, increasing curing depth and adjusting the composite’s permittivity over a wide range. We believe that the proposed strategy for material system establishment can improve the 3D printability of high-permittivity composites and promote other applications of the d-FGMs by the stereolithography technique.

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We conducted a systematic review and meta-analysis to compare the efficacy and safety between laparoscopic reduction (LR) and open reduction (OR) of intussusception in infants and children. Literature searches were conducted to identify studies having compared LR and OR for children with intussusception failed to enema reduction. Parameters such as operative time, time to oral intake, length of hospital stay, overall postoperative complications, and recurrence were pooled and compared by meta-analysis. Among the 502 pediatric participants included in the 11 studies, 275 had received LR and 227 received OR. There were shorter length of hospital stays and time to oral intake with the LR approach compared with OR. However, no significant difference was found between LR and OR in the secondary outcome, such as the overall postoperative complications and recurrence. LR is a feasible, safe, and effective surgical procedure alternative to OR for pediatric intussusception. Compared with OR, LR has the advantage of shorter hospital stay and faster time to oral intake. Besides, the overall postoperative complications may be slightly lower in LR. We conclude that LR should be considered an acceptable option for children.

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