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Understanding the framework of regional urban economic organization and its spatial effect requires a consideration of the networks. Urban network research has increasingly focused on urban spatial interaction and economic spillover effect based on the network externality theory in the context of transition from network research on structural description to performance evaluation. This study focused on Guangdong Province as the research area, built intercity passenger and freight flow networks based on the traffic, people, and express flow, studied the spatial structure of the network using social network analysis and other quantitative methods, and used a spatial Durbin model to estimate the economic spillover effect of the network. The conclusions from the results obtained can be summarized as follows. (1) In the network of traffic and people flow, Guangzhou and Foshan occupy the central positions. The core node of the express flow network spans Guangzhou, Dongguan, and Shenzhen. The spatial distribution of core linkages in the people flow network could be summarized as "the double-channel mode" of Guangzhou-Foshan and Shenzhen-Dongguan, while the corridor distribution of Foshan-Guangzhou-Dongguan-Shenzhen is the dominant flow organization pattern in the traffic flow network. In the express flow network, the dominant flow is dispersed eastward along the coast. (2) Guangzhou serves as the primary controlling entity of the network. Urban nodes clearly differ functionally in the express flow network; however, there is little functional difference in the traffic and people flow networks. (3) According to the spatial regression coefficients based on the SDM of the traffic, people, and the express flow networks, which are -0.974, -1.255, and -8.173, respectively, the economic externality of intercity passenger and freight flow networks reveal a substantial negative spillover. The current growth trend of Guangdong Province is not coordinated or complementary. (4) Coordinated expansion of the regional economy has been facilitated by improved functional connections between urban nodes. In addition, The movement of intercity factors could lower consumer market transaction costs and entrance barriers while allowing regional cities to enjoy the development advantages of borrowed size. However, the improvement of the conditions supporting the business infrastructure has expedited resource siphoning and intensified the province space's agglomeration shadow. This study created urban networks based on the movements of the passenger and freight flows, thereby enriching the empirical investigation of the externality theory in South China. This study also provides some guidance for advancing the regional economic integration and high-quality development.

Inter-city Venture Capital (VC) exchange is a micro-embodiment of the cross-regional flow of innovative elements such as capital and technology, and also an important driving force for shaping the network of VC cities. Compared with other types of investment activities, VC has more advantages in promoting the development of innovative industries, especially high-tech industries, and then driving urban economy and regional development; hence, it is widely regarded as a "catalyst" for economic growth and technological innovation. The study of VC networks is helpful in understanding the financial activity links between cities across the country and provides key support for further rational allocation of financial resources between cities. The existing research rarely uses the actual investment amount of VC transaction events between cities to construct the city network. The analysis of the continuous dynamic evolution research and the influencing factors of the overall spatial network structure over a long period of time needs to be strengthened. To compensate for the shortcomings in the above research, this study uses the data of China's inter-city VC flow between 2000 and 2018 to construct the Chinese urban VC network. The long-term spatial evolution characteristics and overall network structure influencing factors of the national inter-city VC network are discussed based on complex network analysis, GIS spatial technology analysis, multiple linear regression model, and so on. This study derives the following results: (1) The connection between cities tends to be closer, and the agglomeration degree of the national VC network increases, displaying obvious characteristics of high aggregation and small-world network. However, the cyber spatial structure of investors/start-ups tends to be flattened, there is a trend of decentralization. (2) The VC connection between cities has expanded from the eastern coastal axis to the central and western regions as a whole, exhibiting obvious characteristics of path dependence and distance attenuation. Additionally, the VC connection continues to sink from the three major urban agglomerations to other marginal cities, and the core node cities of the network also display a tendency of quantitative expansion and power transfer. (3) The city's entrepreneurial foundation, VC industry development level, financial environment, and urban accessibility all have differentiated impacts on the spatial structure of the national VC network. Moreover, the aforementioned are affected by various mechanisms such as multi-dimensional proximity, urban economy, and path dependence, which promote the construction of national and regional VC networks and the formation and evolution of regional capital centers.

Based on the space of flows theory, this study adopts China Smart Logistics Network big data to build China's e-commerce express logistics network, and explores the spatial structure characteristics of the e-commerce express logistics network, summarizes the regularity of the express logistics flows, finally reveals the formation mechanism of the network through complex network analysis, machine learning algorithms and other methods. The results are as follows: From the node dimension,the spatial inequality characteristics of the importance of e-commerce express logistics in Chinese cities are significant. Taking Heihe-Tengchong Line(Hu Line) as the boundary, the most important cities in the network are distributed within the four major urban agglomerations east of the boundary. The results based on random forest method show that express logistics export-oriented cities form the "e-commerce express logistics export belt" in the southeast coast. Macau and Taiwan receive express logistics input from Beijing-Tianjin-Hebei Urban Agglomeration and Yangtze River Delta Urban Agglomeration respectively on a small scale while Hong Kong plays an important role in logistics distribution function in the network as a high-equilibrium express logistics area. Additionally, from the dimensions of edges and overall network, the network density value is 0.927 0, and the average least connections value is 1.1375, indicating a wide network coverage and relatively complete express logistics routes between cities. Besides, China's e-commerce express logistics network has a small-world effect and high efficiency of the factor flows. A diamond-structured network is also formed with Shanghai, Guangzhou, Chongqing, and Beijing as the four core nodes. In comparison, the Yangtze River Delta Urban Agglomeration is more balanced in the development of e-commerce express logistics; Beijing-Tianjin-Hebei and Chengdu-Chongqing Urban Agglomerations are more dependent on the internal core cities; Guangdong-Hong Kong-Macao Greater Bay Area has the lowest network cohesion, and the express logistics links among Hong Kong, Macao and the other nine cities in the Pearl River Delta are weak. Overall, the network formation is influenced by the development of urban agglomerations. Driven by information technology, traditional and new infrastructure construction, etc., the network is less dependent on the distance factor. Express logistics elements mainly follow the hierarchical diffusion mechanism. This research expands the application of logistics big data in the field of urban network research, reveals the structural characteristics and formation mechanism of China's e-commerce express logistics network, helps enrich the theory of "space of flows", and is also of great significance for understanding the city correlation under the digital economy and the shaping of urban space by modern logistics elements, and promoting the digital transformation and high-quality development of express logistics.

Abnormal metabolism is a major hallmark of cancer and has been validated as a therapeutic target. Adenine monophosphate‐activated protein kinase (AMPK), an αβγ heterotrimer, performs essential functions in cancer progression due to its central role in maintaining the homeostasis of cellular energy. While the contributions of AMPKα and AMPKγ subunits to cancer development have been established, specific roles of AMPKβ1 and AMPKβ2 isoforms in cancer development are poorly understood. Here, we show the functions of AMPKβ1 and AMPKβ2 in colon cancer. Specifically, deletion of AMPKβ1 or AMPKβ2 leads to increased cell proliferation, colony formation, migration, and tumorigenesis in HCT116 and HT29 colon cancer cells. Interestingly, the AMPKβ1 and AMPKβ2 isoforms have slightly different effects on regulating cancer metabolism, as colon cancer cells with AMPKβ1 knockout showed decreased rates of glycolysis-related oxygen consumption, while AMPKβ2 deletion led to enhanced rates of oxygen consumption due to oxidative phosphorylation. These results demonstrate that functional AMPKβ1 and AMPKβ2 inhibit growth and tumorigenesis in colon cancer cells, suggesting their potential as effective targets for colon cancer therapy.

The transportation sector has become one of the largest industrial emissions source of greenhouses gases, such as CO2. What's worse, carbon emissions from this industry has continued to grow in recent years, posing serious challenges to human survival and global environmental security. Among the various transport modes, road transportation yields the highest levels of energy consumption and CO2 emissions. Therefore, scientifically measuring highway carbon emissions and analyzing their spatial differences are of great significance for energy conservation and emission reduction in the transportation sector. Taking Guangdong Province as an example, this study constructs a full-samples and high-precision carbon emissions model, which encompasses Class I~IV passenger cars and Class I~VI freight vehicles based on origin-destination traffic flow data recorded by the highway networking toll system. Finally, the study explores the spatial difference in carbon emissions of highways in Guangdong Province by using geospatial methods. The conclusions are as follows.Firstly, carbon emissions from highways in Guangdong Province mainly came from trucks, which accounted for 57.1% of the total carbon emissions; passenger cars accounted for 42.9%. To be specific, the carbon emissions mainly originated from small and medium-sized vehicles, including Class I passenger vehicles (i.e., cars) and Class I and III freight vehicles. Secondly, the high carbon emissions road sections were spatially auto-correlated, with peak aggregations on national highways, near economically developed and densely populated areas, and adjacent to airports and ports. Road sections with high carbon emissions in Guangdong Province were concentrated along national highways (9,477 t; 61.9%); the carbon emissions of provincial road sections were relatively low (5,834 t; 38.1%). The high-emission sections of passenger vehicles were mainly concentrated in the Pearl River Delta and radially distributed outwards along Guangzhou City. The high-emission sections of freight vehicles were mainly distributed in national highways. The smaller volume of trucks, the more concentrated the spatial distribution of carbon emissions. Furthermore, at the city scale, the cities with higher carbon emissions were mostly concentrated in the Pearl River Delta urban agglomerations, and Guangzhou had a evident primary city effect. The cities with lower carbon emissions were mainly concentrated in coastal areas, such as Zhuhai. At the county scale, the spatial non-equilibrium characteristics of the carbon emissions were significant. The counties with higher carbon emissions were located in the northern part of Guangdong Province and the center and east coast of the Pearl River Delta.Finally, different types of vehicles had differentiated carbon emission characteristics and emission reduction paths. For example, based on the large quantity and significant carbon emissions of Class I passenger vehicles, we must optimize the energy structure to increase the proportion of vehicles using renewable energy sources. Owing to the high unit fuel consumption of Class VI freight vehicles, improving their operation efficiencies is crucial to avoid empty carriages (i.e., no cargo) and we must optimize their driving routes. This research improves the scientificity and spatial analytical accuracy of measuring traffic carbon emissions, thus enriching the sustainable development theory of the transportation, practically promoting the precise emission reduction and green development of the transportation industry, and providing technical and strategic support for attaining dual carbon targets in China.

Volatile organic compounds (VOCs) are a significant source of environmental pollution, posing threats to human safety. With growing concerns about environmental degradation, catalytic oxidation technology emerges as a paramount and widely adopted approach for VOC elimination, renowned for its operational simplicity, energy efficiency, and environmental friendliness. As a representative transition metal catalyst, cobalt‐based catalysts have garnered widespread use in VOC catalytic oxidation due to their cost‐effectiveness, versatility, and distinctive physicochemical properties. This paper provides a detailed exposition of the construction strategies and structure‐activity relationship of Co3O4‐based catalysts in VOCs oxidation reaction, encompassing both monometallic Co3O4 and multimetallic cobalt‐based catalysts. Furthermore, it offers a comprehensive summary and discussion of the latest research progress concerning Co3O4‐based catalysts in practical applications. Concluding with a meticulous analysis, the paper addresses the technical challenges inherent in developing Co3O4‐based catalysts for VOCs degradation. Additionally, it proposes research directions aimed at overcoming these challenges, contributing to the ongoing discourse on environmental sustainability. [ABSTRACT FROM AUTHOR]