The iridium­(III)–cyanine complex (IrCy) was fabricated by conjugating an iridium­(III) complex to a cyanine dye with an intense near-infrared (NIR) absorption. IrCy complex nanoparticles (NPs) with high water solubility and photostability were prepared by a solvent evaporation-induced self-assembly strategy. Considering their effective photacoustic (PA) imaging and generation of 1O2 property with 808 nm laser irradiation in aqueous solution, PA imaging guided NIR-driven photodynamic therapy in vivo was effectively conducted in the 4T1 xenograft model. We developed a real-time PA imaging methodology to investigate the pharmacokinetics, tumor targeting, and biodistribution of IrCy NPs. Taking advantage of the analysis of the PA signal of the common iliac vein, the blood circulation half-life of IrCy NPs in mice was calculated to be ∼18 h, and the enhanced permeability and retention effect of IrCy NPs offered the maximum targeting property in the tumor at about 24 h. The obvious change of PA imaging signal in kidney and bladder confirmed IrCy NPs should be excreted partially from the urine system, and the PA signal decreased from 12.5× to 2.8× in the liver, and from 28.8× to 9.4× in the spleen also confirmed the hepatic metabolic pathway.

Automated fiber placement (AFP) is an advanced manufacturing method for composites, which is especially suitable for large-scale composite components. However, some manufacturing defects inevitably appear in the AFP process, which can affect the mechanical properties of composites. This work aims to investigate the recent works on manufacturing defects and their online detection techniques during the AFP process. The main content focuses on the position defect in conventional and variable stiffness laminates, the relationship between the defects and the mechanical properties, defect control methods, the modeling method for a void defect, and online detection techniques. Following that, the contributions and limitations of the current studies are discussed. Finally, the prospects of future research concerning theoretical and practical engineering applications are pointed out.

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In bone tissue engineering, three-dimensional printed biological scaffolds play an important role in the development of bone regeneration. The ideal scaffolds should have the ability to match the bone degradation rate and osteogenic ability. This article optimizes the unit cell model of the microstructure including spherical pore, gyroid, and topology to explore degradation performance of scaffolds. Boolean operation of array microstructure unit cells and selected part of a computer-aided design (CAD) femur model are adopted to create a reconstructed scaffold model. Polylactic acid/[Formula: see text]-tricalcium phosphate/hydroxyapatite scaffolds with spherical pore, gyroid, and topology-optimized structures are manufactured by three-dimensional printing utilizing the composition of bio-ink including polylactic acid, [Formula: see text]-tricalcium phosphate, and hydroxyapatite. After degradation of the scaffolds in vitro for several days, the mechanical properties are analyzed to study the effects of different microstructures on the degradation properties. The results show that the gyroid scaffolds with favorable degradability still maintain excellent mechanical properties after degradation. Mechanical properties of the scaffolds with topology-optimized structure and spherical pore microstructure scaffolds have a significant decrease after degradation.

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