Interlayer reinforcement of 3D printed concrete by the in-process deposition of U-nails

3D concrete printing has tremendous potential for construction manufacturing; however, weak interface bonding between adjacent layers remains a well-known issue that affects the mechanical properties of printed structures. The layers introduce anisotropy and reduce the capacity to resist tensile and shear loads. Reinforcements, inserted perpendicular to the printed layers to traverse the interfaces, can improve these limitations, but the insertion of reinforcements is difficult to achieve in practice, and there are few published studies exploring appropriate methods. This study presents a promising approach using U-shaped nails inserted into concrete during the printing process. The bridging effect and dowel action of the applied U-nails are visualised and analysed to elucidate the toughness improvement. The ultimate tensile strength and shear strength of 3D printed concrete are significantly increased by 145.0% and 220.0%, respectively. U-nails with a filament thickness of 2–2.5 mm are recommended to yield optimal improvement in the interlayer strength

Additional file 1 of Inhalable CAR-T cell-derived exosomes as paclitaxel carriers for treating lung cancer

Additional file 1: Figure S1. The purity of different batches of CAR-Exos. Exosome purity level required for preclinical studies: 1 × 1011 particle/mg. Figure S2. Representative TEM image of PTX@CAR-Exo. Scale bar: 100 nm. Size distribution and zeta potential of CAR-Exo and PTX@CAR-Exo measured by NTA and DLS. Data are presented as the mean ± SD of three biological replicates. Figure S3. Determination of the standard curve for detecting PTX using a spectrophotometer. Mass of PTX = 0.77636 × OD value − 0.01551. Figure S4. Storage stability of CAR-Exo or PTX@CAR-Exo at − 80 °C. The average size of PTX@CAR-Exo did not change within 30 days at − 80 °C. Data are presented as the mean ± SD of three biological replicates. Figure S5. Representative histological images for H&E staining were obtained from the lung, liver, spleen, heart, and kidney of mice with different treatments post inhalation. Scale bars: 100 µm. Body weights of control mice and mice receiving different treatments. Serum ALT, ALP, and AST levels in mice from different treatments were used as indicators of liver injury. Serum CRE and BUN levels in mice from different treatments were used as indicators of kidney function. Data are presented as the mean ± SD of three biological replicates. PBS, T-Exo, CAR-Exo, PTX@CAR-Exo. Figure S6. The targeting of CAR-Exos to the orthotopic lung cancer in vivo. The accumulation of inhaled CAR-Exos labeled with DiR post administration were measured by IVIS system. Figure S7. Survival analysis of tumor-bearing mice after CAR-Exos inhalation. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001, ns: not significant. Figure S8. Cytokine concentrations in mouse peripheral blood following intravenous CAR-T cells administration or inhalation of CAR-Exos. Data are presented as the mean ± SD of three biological replicates. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001, ns: not significant

Flexible and Degradable Paper-Based Strain Sensor with Low Cost

It is a challenge to fabricate low-cost and flexible electronic devices with degradable materials. In this work, a flexible and degradable strain sensor was fabricated on a paper substrate by dip-coating in an aqueous suspension of carbon black (CB) and carboxymethyl cellulose (CMC). The composition of CB and CMC in the suspension was first studied for producing a uniform conducting layer on the paper. Then the strain sensor was obtained by assembling the coated paper and wires with silver paste. The sensor exhibits gauge factor of 4.3 and responsive time of approximately 240 ms, demonstrating the capability of monitoring various human motions with high stability >1000 cycles. The microgaps between CB particles and cracks on the surface of the CB layer can account for this resistive-type sensitivity. The degradation test shows that the sensor can be degraded soon under gentle rubbing in wet state, implying it is an environmentally friendly “green” electronic device. Furthermore, the cost of the sensor is quite low (<$0.001/sensor) due to the cheap raw materials used, which provides an opportunity for its future utilization in various intelligent systems