Tunable synaptic behaviors of solution-processed InGaO films for artificial visual systems.

Due to their persistent photoconductivity, amorphous metal oxide thin films are promising for construction of artificial visual systems. In this work, large-scale, uniformly distributed amorphous InGaO thin films with an adjustable In/Ga ratio and thickness are prepared successfully by a low-cost environmentally friendly and easy-to-handle solution process for constructing artificial visual systems. With the increase of the In/Ga ratio and film thickness, the number of oxygen vacancies increases, along with the increase of post-synaptic current triggered by illumination, benefiting the transition of short-term plasticity to long-term plasticity.

Toward High-Performance Self-Powered Near-Ultraviolet Photodetection by Constructing a Unipolar Heterojunction.

Constructing a unipolar heterojunction is an effective energy band engineering strategy to improve the performance of photoelectric devices, which could suppress dark current and enhance detectivity by modulating the transfer of carriers. In this work, unipolar heterojunctions of Si/PbI and GaSb/PbI are constructed successfully for high-performance self-powered near-ultraviolet photodetection. Owing to the unique band offset of unipolar heterojunctions, the transport of holes is blocked, and only photogenerated electrons in PbI can flow unimpeded under the driving force of the built-in electric field.

Tunable Contacts of Bi O Se Nanosheets MSM Photodetectors by Metal-Assisted Transfer Approach for Self-Powered Near-Infrared Photodetection.

Owing to the Fermi pinning effect arose in the metal electrodes deposition process, metal-semiconductor contact is always independent on the work function, which challenges the next-generation optoelectronic devices. In this work, a metal-assisted transfer approach is developed to transfer Bi O Se nanosheets onto the pre-deposited metal electrodes, benefiting to the tunable metal-semiconductor contact. The success in Bi O Se nanosheets transfer is contributed to the stronger van der Waals adhesion of metal electrodes than that of growth substrates.

Time trends and endoscopic management of foreign body ingestion in the upper GI tract: a retrospective analysis of 1,152 cases in China.

Objectives: foreign body ingestions are encountered in the clinical practice and sometimes require endoscopic management. However, time trends and epidemiology of these cases have not been fully clarified. Whether seasons and festivals have an effect on the occurrence has been poorly described.