[Carbon Emission Reduction Effect of Spatial Correlation Network Structure Characteristics: From the Perspective of Urban Agglomeration]

Based on social network and regression analyses, this study conducted research with regard to the spatial correlation and effect of carbon emissions in urban agglomerations of the Pearl River Delta (PRD) with the data of prefecture-level cities in Pearl River Delta urban agglomerations from 2001 to 2019. As the results suggested, ① the carbon emission links among cities in PRD urban agglomerations were relatively loose, the subordinate structure changed frequently, and the carbon emission exchanges and cooperation among cities need to be strengthened. ② The core-periphery structure of the spatial correlation network of carbon emissions was loose to a certain extent, the control ability of the central city to the overall network structure was weakened, and the marginal cities gradually changed from being controlled to adopting a controlling role. ③ The improvement in the overall network tightness and stability and the breaking of the network hierarchical structure significantly reduced regional carbon emissions, whereas the improvement in individual network centrality significantly promoted urban carbon emission reduction. The above analysis will help to provide reference for coordinating carbon dioxide emission reduction and low-carbon city development policies.

Integrated molecular and affiliation network analysis: Core-periphery social clustering is associated with HIV transmission patterns

This study investigates the two-mode core-periphery structures of venue affiliation networks of younger Black men who have sex with men (YBMSM). We examined the association between these structures and HIV phylogenetic clusters, defined as members who share highly similar HIV strains that are regarded as a proxy for sexual affiliation networks. Using data from 114 YBMSM who are living with HIV in two large U.S. cities, we found that HIV phylogenetic clustering patterns were associated with social clustering patterns whose members share affiliation with core venues that overlap with those of YBMSM. Distinct HIV transmission patterns were found in each city, a finding that can help to inform tailored venue-based and network intervention strategies.

A multi-agent model to study epidemic spreading and vaccination strategies in an urban-like environment

Worldwide urbanization calls for a deeper understanding of epidemic spreading within urban environments. Here, we tackle this problem through an agent-based model, in which agents move in a two-dimensional physical space and interact according to proximity criteria. The planar space comprises several locations, which represent bounded regions of the urban space. Based on empirical evidence, we consider locations of different density and place them in a core-periphery structure, with higher density in the central areas and lower density in the peripheral ones. Each agent is assigned to a base location, which represents where their home is. Through analytical tools and numerical techniques, we study the formation mechanism of the network of contacts, which is characterized by the emergence of heterogeneous interaction patterns. We put forward an extensive simulation campaign to analyze the onset and evolution of contagious diseases spreading in the urban environment. Interestingly, we find that, in the presence of a core-periphery structure, the diffusion of the disease is not affected by the time agents spend inside their base location before leaving it, but it is influenced by their motion outside their base location: a strong tendency to return to the base location favors the spreading of the disease. A simplified one-dimensional version of the model is examined to gain analytical insight into the spreading process and support our numerical findings. Finally, we investigate the effectiveness of vaccination campaigns, supporting the intuition that vaccination in central and dense areas should be prioritized.