Xinhua Pan

Honeycomb-like NiO/ZnO heterostructured nanorods (NRs) were fabricated by a simple photochemical deposition method. The morphology of the NiO nanostructures can be rationally tailored by changing the concentration of the solution, reaction time and annealing temperature. A reasonable formation mechanism of the honeycomb-like NiO/ZnO NRs is proposed, which is closely related to the production of OH− in the vicinity of ZnO NRs during the photochemical deposition process. The fabricated NiO/ZnO p–n heterojunction shows a well-defined rectifying characteristic with a turn-on voltage of 0.66 V and a negligible leakage current. Moreover, the UV detection performance increases considerably compared to that of bare ZnO NRs, which is attributed to the change of nanostructure and the extended carrier depletion region near p-NiO/n-ZnO junctions.

Retina-inspired visual sensors play a crucial role in the realization of neuromorphic visual systems. Nevertheless, significant obstacles persist in the pursuit of achieving bidirectional synaptic behavior and attaining high performance in the context of photostimulation. In this study, we propose a reconfigurable all-optical controlled synaptic device based on the IGZO/SnO/SnS heterostructure, which integrates sensing, storage and processing functions. Relying on the simple heterojunction stack structure and the role of energy band engineering, synaptic excitatory and inhibitory behaviors can be observed under the light stimulation of ultraviolet (266 nm) and visible light (405, 520 and 658 nm) without additional voltage modulation. In particular, junction field-effect transistors based on the IGZO/SnO/SnS heterostructure were fabricated to elucidate the underlying bidirectional photoresponse mechanism. In addition to optical signal processing, an artificial neural network simulator based on the optoelectrical synapse was trained and recognized handwritten numerals with a recognition rate of 91%. Furthermore, we prepared an 8 × 8 optoelectrical synaptic array and successfully demonstrated the process of perception and memory for image recognition in the human brain, as well as simulated the situation of damage to the retina by ultraviolet light. This work provides an effective strategy for the development of high-performance all-optical controlled optoelectronic synapses and a practical approach to the design of multifunctional artificial neural vision systems.

Abstract Research on tumour cell‐derived small extracellular vesicles (sEVs) that regulate tumour microenvironment (TME) has provided strategies for targeted therapy of head and neck squamous cell carcinoma (HNSCC). Herein, we demonstrated that sEVs derived from HNSCC cancer cells carried CD73 (sEVs CD73 ), which promoted malignant progression and mediated immune evasion. The sEVs CD73 phagocytosed by tumour‐associated macrophages (TAMs) in the TME induced immunosuppression. Higher CD73 high TAMs infiltration levels in the HNSCC microenvironment were correlated with poorer prognosis, while sEVs CD73 activated the NF‐κB pathway in TAMs, thereby inhibiting immune function by increasing cytokines secretion such as IL‐6, IL‐10, TNF‐α, and TGF‐β1. The absence of sEVs CD73 enhanced the sensitivity of anti‐PD‐1 therapy through reversed immunosuppression. Moreover, circulating sEVs CD73 increased the risk of lymph node metastasis and worse prognosis. Taken together, our study suggests that sEVs CD73 derived from tumour cells contributes to immunosuppression and is a potential predictor of anti‐PD‐1 responses for immune checkpoint therapy in HNSCC.