S C Lyu

Current global climate change, increasing energy depletion, and continuous environmental degradation have made it crucial to transform the economic development model into a low-carbon economy. Urban development, being one of the major sources of carbon emissions, has made low-carbon and ecological urban development an important topic on the international agenda. This article uses principal component analysis and the entropy weight method to quantitatively evaluate the development of low-carbon ecological cities in Guangdong Province from three aspects: economic and social factors, living environment, and resource and environmental factors. Based on the current situation, it proposes development strategies to provide references and guidance for further low-carbon ecological economic development in Guangdong Province. In the current world situation, with global climate warming, increasing energy depletion, and continuous environmental deterioration, the transformation of the economic development model into a low-carbon economy is of great significance. Urban development, being a major source of carbon emissions, makes low-carbon and ecological urban development an increasingly prominent topic in international societal development. This paper quantitatively evaluates the development of low-carbon and ecological cities in Guangdong Province using principal component analysis (PCA) and the entropy weight method. The results indicate that economic and social development plays a decisive role in the development of low-carbon cities. Strategies for development are proposed in response to the current situation, providing guidance and reference for further progress toward a low-carbon and ecological economy in Guangdong Province.

Objective: To analyze the changes on gut microbiota and metabolic products in patients with chronic heart failure. Methods: By searching the Pubmed, EMBASE, Cochrane Library, and CNKI, Wanfang, and CMB databases from the day of built up to December 2019, we screened related literature exploring the intestinal flora of chronic heart failure patients, and systematic review was performed to study changes in intestinal flora composition, function, and metabolites among chronic heart failure patients. Results: A total of 10 articles were included to study the gut microbiota of patients with chronic heart failure in this analysis. The systematic review showed significant changes in β-diversity in patients with heart failure. The abundance of faecalibacterium, blautia, bacteroides, prevotella and anaerostipes was decreased, while the abundance of streptococcus, escherichia/shigella, veillonella, and enterobacte was increased. The increased microbial gene function in patients with heart failure included tryptophan metabolism, lipid metabolism, LPS synthesis,and so on, especially, bacterial genes related to trimethylamine oxide production increased significantly, while genes related to key enzymes producing the beneficial metabolite butyrate decreased significantly, and harmful metabolite trimethylamine oxide levels increased in chronic heart failure patients. Conclusion: There are significant changes in the structure, function and metabolites of intestinal flora in patients with chronic heart failure.