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Non‐invasive human‐machine interactions (HMIs) are expected to be promoted by epidermal tactile receptive devices that can accurately perceive human activities. In reality, however, the HMI efficiency is limited by the unsatisfactory perception capability of mechanosensors and the complicated techniques for device fabrication and integration. Herein, a paradigm is presented for high‐throughput fabrication of multimodal epidermal mechanosensors based on a sequential "femtosecond laser patterning‐elastomer infiltration‐physical transfer" process. The resilient mechanosensor features a unique hybrid sensing layer of rigid cellular graphitic flakes (CGF)‐soft elastomer. The continuous microcracking of CGF under strain enables a sharp reduction in conductive pathways, while the soft elastomer within the framework sustains mechanical robustness of the structure. As a result, the mechanosensor achieves an ultrahigh sensitivity in a broad strain range (GF of 371.4 in the first linear range of 0–50%, and maximum GF of 8922.6 in the range of 61–70%), a low detection limit (0.01%), and a fast response/recovery behavior (2.6/2.1 ms). The device also exhibits excellent sensing performances to multimodal mechanical stimuli, enabling high‐fidelity monitoring of full‐range human motions. As proof‐of‐concept demonstrations, multi‐pixel mechanosensor arrays are constructed and implemented in a robot hand controlling system and a security system, providing a platform toward efficient HMIs. [ABSTRACT FROM AUTHOR]

Simple Summary: Tachykinin1 (tac1) gene products participate in the regulation of hormone secretion in the pituitary of Dabry's sturgeon. Two products of tac1 gene, Substance P (SP) and neurokinin A (NKA), were initially confirmed to regulate the gene expression of two gonadotropins (lh and fsh) in the Dabry's sturgeon pituitary tissue by intraperitoneal injection in vivo and co-culture of primary cells in vitro. This research presents the initial investigation into the reproductive role of SP and NKA in Dabry's sturgeon, offering a valuable insights for advancing efficient ripening techniques in artificial breeding of sturgeon. As an ancient and endangered species unique to the Yangtze River in China, the wild population of the Dabry's sturgeon has become scarce. Due to the long time till the first sexual maturity of Dabry's sturgeon, the population of artificially bred Dabry's sturgeon recovered slowly. As a member of the tachykinin family, TAC1 has been reported to have a variety of functions in mammals such as pain control, smooth muscle contraction and reproductive cycle regulation, but the function of Tac1 in fish has been rarely reported. In this study, we synthesized two tac1 gene products, Substance P (SP) and neurokinin A (NKA), and further verified the effect of two tac1 gene products on the secretion of related hormones in the pituitary of Dabry's Sturgeon by intraperitoneal injection and co-culture of primary cells. Expression studies revealed that the newly cloned tac1 were mainly distributed in the hypothalamus and pituitary tissue of the brain. In prepubertal Dabry's sturgeon, this study showed that the two gonadotropins' mRNA levels in pituitary tissue can be significantly increased by SP and NKA through intraperitoneal injection, and the LH protein level in serum was also increased. Further study showed that both NKA and SP could promote the two gonadotropins' mRNA expression in pituitary cells of Dabry's sturgeon. In addition, we explored the optimal dose and time of SP and NKA on pituitary cells is 24 h and over 10 nM. These results, as a whole, suggested that tac1 gene products play an important role in gonadotropin release and gonadal development in prepubertal Dabry's sturgeon. [ABSTRACT FROM AUTHOR]

Compared with conventional water-filled tensiometers, polymer-filled osmotic tensiometers (OTs) can measure a higher matric suction by increasing the osmotic pressure of the water inside the tensiometer. The measuring range of an OT is equal to the osmotic pressure of water inside the OT. All previous research has used commercial polymers in developing OTs and the mechanism of long-term pressure decay of OTs was not found. In this study, polymers including polyacrylamide (PAM) and sodium polyacrylate (NaPA) with different degrees of cross-linking were synthesised by ultraviolet polymerisation to develop new OTs. Long-term pressure variations of OTs indicated that the pressure decay was more likely due to the stress relaxation of polymer materials instead of polymer leakage. PAM-filled OTs have a faster stress relaxation behaviour than NaPA-filled OTs, so that they can keep constant pressure (i.e. constant measuring range) for a long time and there is no need for pressure correction based on the pressure decay rate. However, the measuring range of PAM-filled OTs is lower than that of NaPA-filled OTs. The result of matric suction measurements demonstrated that the proposed OTs can be used to measure matric suction both in low and high ranges with fast response and high accuracy. [ABSTRACT FROM AUTHOR]