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To investigate the potential for further enhancing the cracking resistance of thin-walled UHPC by prestressing, the uniaxial tensile and three-point bending experiments for UHPC specimens reinforced with iron-based shape memory alloy (Fe-SMA) wires were conducted. The specimens were placed in an oven and heated to 150 °C, 200 °C, and 250 °C, which was intended to activate the Fe-SMA wires to produce self-prestress. The characteristics of different reinforced methods and heating temperatures were systematically compared. The cracking load and the crack development were recorded using Digital Image Correlation (DIC) techniques. The result shows that at the temperature of 150 ºC, compared to the dog-bone shaped specimens without reinforcement and the specimens with steel wires, the mean cracking load of specimens with Fe-SMA wires was enhanced by 13.4% and 9.8%, respectively. The study preliminary verified that this method can activate Fe-SMA inside UHPC. [ABSTRACT FROM AUTHOR]

Neuropeptide Y (NPY), a 36‐amino‐acid peptide, functions as a neurotransmitter in both the central and peripheral nervous systems by activating the NPY receptor subfamily. Notably, NPY analogs display varying selectivity and exert diverse physiological effects through their interactions with this receptor family. [Pro34]–NPY and [Leu31, Pro34]–NPY, mainly acting on Y1R, reportedly increases blood pressure and postsynaptically potentiates the effect of other vasoactive substances above all, while N‐terminal cleaved NPY variants in human body primary mediates angiogenesis and neurotransmitter release inhibition through Y2R. However, the recognition mechanisms of Y1R and Y2R with specific agonists remain elusive, thereby hindering subtype receptor‐selective drug development. In this study, we report three cryo‐electron microscopy (cryo‐EM) structures of Gi2‐coupled Y1R and Y2R in complexes with NPY, as well as Y1R bound to a selective agonist [Leu31, Pro34]–NPY. Combined with cell‐based assays, our study not only reveals the conserved peptide‐binding mode of NPY receptors but also identifies an additional sub‐pocket that confers ligand selectivity. Moreover, our analysis of Y1R evolutionary dynamics suggests that this sub‐pocket has undergone functional adaptive evolution across different species. Collectively, our findings shed light on the molecular underpinnings of neuropeptide recognition and receptor activation, and they present a promising avenue for the design of selective drugs targeting the NPY receptor family. [ABSTRACT FROM AUTHOR]

This paper aimed to investigate the mechanical performances of woven tube-reinforced cementitious composites. Polyoxymethylene fibers were used to form woven tubes. The integrated woven tube and splicing woven tube-reinforced cementitious composites were prepared with different textile structures. The compressive and bending properties of woven tube-reinforced cementitious composites were experimentally characterized through compression and bending tests, and the testing processes were recorded by camera. The results showed that both the integrated woven tube and the splicing woven tube could apparently enhance the compressive and bending properties. The compressive and bending strengths of the integrated woven tube-reinforced cementitious composite could reach 44 and 21 MPa, respectively. Due to low splicing strength, the splicing woven tube-reinforced cementitious composite was likely to split, which led to the disassembly. The integrated woven tube-reinforced cementitious composite had higher compressive and bending strengths than the splicing woven tube-reinforced cementitious composite. Moreover, the integrated woven tube-reinforced cementitious composite exhibited better energy absorption ability and integrity after testing than the splicing woven tube-reinforced cementitious composite. The energy absorption of the integrated woven tube-reinforced cementitious composite could reach over 7 MJ/m3 during compression. Under compression, the splicing woven tube-reinforced cementitious composite and pure cement only had one compressive peak stress, which was caused by the damage to the cement, whereas the integrated woven tube-reinforced cementitious composite had two compressive peak stresses: the second compressive peak stress was caused by fiber breakage. In general, the integrated woven tube is more suitable for reinforcing cement than the splicing woven tube. [ABSTRACT FROM AUTHOR]