As an indispensable component in human beings, the acetylcholine system regulates multiple physiological processes not only in neuronal tissues but also in nonneuronal tissues. However, since the concept of the “Nonneuronal cholinergic system (NNCS)” has been proposed, the role of the acetylcholine system in nonneuronal tissues has received increasing attention. A growing body of research shows that the acetylcholine system also participates in modulating inflammatory responses, regulating contraction and mucus secretion of respiratory tracts, and influencing the metastasis and invasion of lung cancer. In addition, the susceptibility and severity of respiratory tract infections caused by pathogens such as Mycobacterium Tuberculosis and the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) can also correlate with the regulation of the acetylcholine system. In this review, we summarized the major roles of the acetylcholine system in respiratory diseases. Despite existing achievements in the field of the acetylcholine system, we hope that more in-depth investigations on this topic will be conducted to unearth more possible pharmaceutical applications for the treatment of diverse respiratory diseases.

Magnetic semiconductors have become a widely studied direction in spintronic materials due to their unique energy band structure and two different spin transport channels. In this work, we imported rare-earth atoms into quaternary Heusler compounds and considered on Slater-Pauling rules. Magnetic semiconductors FeCrYSn, FeCrYGe, FeCrLuGe, FeCrLuSn, FeCrLuSi, FeVLuSb, MnCrYSb, and MnCrLuSb were found through first-principle calculations. According to the result, the band gaps of these quaternary Heusler compounds are extremely narrow.

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