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BACKGROUND: This prospective randomized controlled study compared the short- and long-term efficacy and advantages of modified Park's submucosal over Milligan-Morgan hemorrhoidectomy (MMH) in the treatment of grade III and IV circumferential prolapsed hemorrhoids (CPH). METHODS: A total of 186 consecutive patients with grade III or IV CPH were enrolled. The patients were randomized to MPSH (n = 93) or MMH (n = 93) treatment groups. Patient data included demographics, clinical characteristics, surgical parameters, underlying or arising complications, and CPH recurrence. The patients were closely followed up for at least 24 months. RESULTS: The patient demographic data and clinical parameters were comparable in the two groups (P > 0.05). MPSH took significantly longer operative time (P < 0.05). Although there was no significant difference in mean postoperative pain between the two groups at days 3 and 14, pain at day 7 was significantly more frequent and severe in the MMH group (P < 0.05). There were no significant group differences in postoperative bleeding, intraoperative blood loss, or development of anal stenosis (P > 0.05). However, the cumulative relapse-free rate was substantially higher in the MPSH group (P < 0.05). CONCLUSION: MPSH and MMH are both practical and safe techniques for treating grade III and IV CPH disease. However, MPSH is safer, easier, and faster to perform and is associated with fewer recurrences within 24 months of surgery. Additional clinical studies are needed to validate these conclusions.

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Highly efficient shielding materials with an excellent electromagnetic wave absorption have gained increased attention. A new design was used to provide cellulose paper with a high electromagnetic shielding effectiveness (EMI SE) and improve the absorption performance by constructing an asymmetry sandwich structure that consisted of a dense nickel coating, Fe3O4 nanoparticles and a porous nickel layer. This unique structure caused a "multiple reflection-absorb-reflection" process when the electromagnetic waves penetrated the sample. The EMI absorption (SEA) and total SE (SET) increased with Fe3O4 absorption time increasing at 8.2-12.4 GHz, which was attributed to the synergistic effect between porous nickel layer and Fe3O4 nanoparticles. The SEA and SET of the sample with a thickness of 0.195 mm can achieved 18.57 and 41.88 dB, respectively. The design was conducive to improving the magnetic and corrosion resistance properties. This study provided a novel path to obtain a low cost and lightweight electromagnetic shielding material that can reduce secondary radiation.

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The functional design of paper-based material surfaces with renewable functions and environmentally friendly properties is prevalent nowadays. Herein, a superhydrophobic surface with a coral reef-like structure was prepared on filter paper by electroless copper plating, rapid silver nitrate etching, and facile 1-hexadecanethiol impregnation. After low-surface-energy thiol treatment, this unique coral reef-like structure surface showed excellent superhydrophobicity with a water contact angle of 163.8° and superoleophobicity with an oil contact angle of 0°, which could be used for oil-water separation and had a separation efficiency above 89.17% after 12 consecutive oil-water separations. Because the copper layer and silver nanostructure are both excellent conductive materials, the modified paper exhibited excellent electromagnetic shielding properties, and the electromagnetic interface shielding effectiveness exceeded 63 dB from 9 kHz to 1.5 GHz. The modified paper also had excellent self-cleaning properties and a better corrosion resistance. The unique three-dimensional interweaving structure between the cellulose fibers in the filter paper is fully utilized, and the substitution reaction between the silver ion and the copper coating produces a coral reef-like structure, which provides a new strategy for promoting the wide application of paper-based materials.