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Newly developed oblique photogrammetry (OP) techniques based on unmanned aerial vehicles (UAVs) equipped with multicamera imaging systems are widely used in many fields. Smartphones cost less than the cameras commonly used in the existing UAV OP system, providing high-resolution images from a built-in imaging sensor. In this paper, we design and implement a novel low-cost and ultralight UAV OP system based on smartphones. Firstly, five digital cameras and their accessories detached from the smartphones are then fitted into a very small device to synchronously shoot images at five different perspective angles. An independent automatic capture control system is also developed to realize this function. The proposed smartphone-based multicamera imaging system is then mounted on a modified version of an existing lightweight UAV platform to form a UAV OP system. Three typical application examples are then considered to evaluate the performance of this system through practical experiments. Our results indicate that both horizontal and vertical location accuracy of the generated 3D models in all three test applications achieve centimeter-level accuracy with respect to different ground sampling distances (GSDs) of 1.2 cm, 2.3 cm, and 3.1 cm. The accuracy of the two types of vector maps derived from the corresponding 3D models also meet the requirements set by the surveying and mapping standards. The textural quality reflected by the 3D models and digital ortho maps (DOMs) are also distinguishable and clearly represent the actual color of different ground objects. Our experimental results confirm the quality and accuracy of our system. Although flight efficiency and the accuracy of our designed UAV OP system are lower than that of the commercial versions, it provides several unique features including very low-cost, ultralightweight, and significantly easier operation and maintenance.

Alcohol liver disease (ALD) caused by excessive alcohol consumption is a progressive disease, and alcohol fatty liver disease is the primary stage. Currently, there is no approved drug for its treatment. Abstinence is the best way to heal, but patients’ compliance is poor. Unlike other chronic diseases, alcohol fatty liver disease is not caused by nutritional deficiencies; it is caused by the molecular action of ingested alcohol and its metabolites. More and more studies have shown the potential of Penthorum chinense Pursh (PCP) in the clinical use of alcohol fatty liver treatment. The purpose of this paper is to reveal from the essence of PCP treatment of alcohol liver mechanism mainly by the ethanol dehydrogenase (ADH) and microsomal ethanol oxidation system-dependent cytochrome P4502E1 (CYP2E1) to exert antilipogenesis, antioxidant, anti-inflammatory, antiapoptotic, and autophagy effects, with special emphasis on its mechanisms related to SIRT1/AMPK, KEAP-1/Nrf2, and TLR4/NF-κB. Overall, data from the literature shows that PCP appears to be a promising hepatoprotective traditional Chinese medicine (TCM).

Nonalcoholic fatty liver disease, a type of metabolic syndrome, continues to rise globally. Currently, there is no approved drug for its treatment. Improving lifestyle and exercise can alleviate symptoms, but patients’ compliance is poor. More and more studies have shown the potential of Polygoni Multiflori Radix (PMR) in the treatment of NAFLD and metabolic syndrome. Therefore, this paper reviews the pharmacological effects of PMR and its main chemical components (tetrahydroxystilbene glucoside, emodin, and resveratrol) on NAFLD. PMR can inhibit the production of fatty acids and promote the decomposition of triglycerides, reduce inflammation, and inhibit the occurrence of liver fibrosis. At the same time, it maintains an oxidation equilibrium status in the body, to achieve the therapeutic purpose of NAFLD and metabolic syndrome. Although more standardized studies and clinical trials are needed to confirm its efficacy, PMR may be a potential drug for the treatment of NAFLD and its complications. However, the occurrence of adverse reactions of PMR has affected its extensive clinical application. Therefore, it is necessary to further study its toxicity mechanism, enhance efficacy and control toxicity, and even reduce toxicity, which will contribute to the safe clinical use of PMR.