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4D printing enables 3D printed structures to change shape over "time" in response to environmental stimulus. Because of relatively high modulus, shape memory polymers (SMPs) have been widely used for 4D printing. However, most SMPs for 4D printing are thermosets, which only have one permanent shape. Despite the efforts that implement covalent adaptable networks (CANs) into SMPs to achieve shape reconfigurability, weak thermomechanical properties of the current CAN-SMPs exclude them from practical applications. Here, we report reconfigurable 4D printing via mechanically robust CAN-SMPs (MRC-SMPs), which have high deformability at both programming and reconfiguration temperatures (>1400%), high Tg (75°C), and high room temperature modulus (1.06 GPa). The high printability for DLP high-resolution 3D printing allows MRC-SMPs to create highly complex SMP 3D structures that can be reconfigured multiple times under large deformation. The demonstrations show that the reconfigurable 4D printing allows one printed SMP structure to fulfill multiple tasks.. [ABSTRACT FROM AUTHOR]

A PCM was added to filling materials in an appropriate proportion to realize the effective collection and storage of geothermal energy. Based on the theory of heat transfer and similarity, the heat-storage performance of filling body was numerically simulated in different states, then, the influences of paraffin proportion, initial temperature of filling body, surrounding rock temperature, stope air-flow temperature, and velocity on the heat-storage behavior of filling body were analyzed. The results revealed that reducing the initial heat-storage temperature of filling body, increasing surrounding rock temperature, and increasing the air-flow temperature in the stope all effectively increased the heatstorage capacity of filling body. In which the influence of initial temperature and surrounding rock temperature were more significant. At the end of 16 hours heatstorage period, when the initial temperature of filling body was reduced from 24 °C to 18 °C, the heat transfer capacity of filling body without paraffin and that with 5% paraffin decreased by 2.85 · 103 kJ and 2.40 · 103 kJ, respectively. When surrounding rock temperature increased from 35 °C to 45 °C, the amount of heat stored by two bodies increased by 3.89 · 103 kJ and 4.51 · 103 kJ, respectively. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate whether diminazene attenuates myocardial infarction (MI) in rats. In addition, the present study investigated whether ACE2 signaling was involved in the effects of diminazene on protein function. A rat model of acute myocardial infarction (AMI) was established by occlusion of the left anterior descending coronary artery. The AMI model rats received intraperitoneal injections of diminazene (5 mg/kg/day) for 3 days. Treatment with diminazene significantly inhibited the expression of casein kinase and lactate dehydrogenase, and reduced infarct size in AMI rats. The findings indicated that diminazene significantly reduced the levels of inflammatory factors including tumor necrosis factor‑α and interleukin‑6, suppressed the protein expression of cytochrome c oxidase subunit 2 (COX‑2) and inducible nitric oxide synthase (iNOS), and activated angiotensin‑converting enzyme 2 (ACE2), angiotensin II receptor type 1 (AT1R) and MAS1 proto‑oncogene, G protein‑coupled receptor (MasR) protein expression in AMI model rats. In conclusion, the present study demonstrated that diminazene attenuated AMI in rats via suppression of inflammation, reduction of COX‑2 and iNOS expression, and activation of the ACE2/AT1R/MasR signaling pathway. [ABSTRACT FROM AUTHOR]