This article proposes an adaptive back‐stepping flight controller under angle of attack (AOA) constraints. Taking the hypersonic flight vehicle (HFV) for example, considering the AOA constraints caused by the scramjet intake requirements, the asymmetric integral barrier Lyapunov function is used to design the controller, while the AOA is directly limited to a predefined interval without setting the tracking error and virtual control constraints separately. Furthermore, the neural networks and disturbance observer are applied in the controller to deal with the model uncertainty and external disturbance. The system stability and the AOA constraints are proved via Lyapunov analysis. Simulation tests on HFV longitudinal dynamics present that the proposed controller can prevent the AOA from exceeding the given bounds while altitude and velocity tracking.

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Background: Diabetes and periodontitis are common chronic diseases, and the pathogeneses of the 2 diseases both involve chronic inflammation. The presence of either of the 2 diseases increases the risk of the other, while the treatment of 1 can reduce the risk of the other. This study sought to summarize the current status of research in this field via a bibliometric analysis. Methods:The Science Citation Index Expanded (SCI-E) database was searched to retrieve relevant articles using the following search terms: "periodontitis" and "diabetes". Citespace software was used to analyze the search results, including the number of citations, the distribution of the countries, institutions, and journals that published the articles, the distribution of the authors, and the use of keywords in the articles.Results: A total of 2,151 articles, with 63,668 citations, were included in the analysis. The top 5 countries in terms of the number of published papers were the United States (US), China, Brazil, Japan, and the United Kingdom (UK), and the top 5 institutions in terms of the number of published papers were Columbia

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