Southern City Research Articles

The polarisation of Italian metropolitan areas, 2000–2018: structural change, technology and growth

Abstract Large cities are a key driver of technological innovation and economic growth. This paper investigates the developments of Italian metropolitan areas, building on insights from economic geography and innovation studies. The key questions to be investigated are the following: (i) Which trajectories of population and economic change can be identified for Italian metropolitan areas? Are we facing a process of economic and technological polarisation that may worsen the country’s imbalances? (ii) What is the role played in such developments by technological and structural change, and in particular by digital technologies and the rise of finance? The empirical analysis investigates the patterns of technological and economic indicators for the period 2000–2018 for 14 Italian metropolitan areas, proxied by their provinces, providing evidence of growing polarisation between Milan, where most positive developments are concentrated, and the other metropolitan zones. Rome has been losing ground in most fields; Venice and Genoa are characterised by industrial decline. Few mid-sized cities show some economic dynamism—including Bologna and Cagliari—while most southern and insular Italian cities increase their gap relative to the performances of leading metropolitan areas.

Evaluating the influence of human disturbance on the ecosystem service scarcity value: an insightful exploration in Guangxi region

Investigating how human disturbance affects the ecosystem service scarcity value (ESSV) is crucial for maintaining ecosystem stability and achieving sustainable development goals (SDGs). This study separately assessed ESSV and human disturbance in Guangxi from 1990 to 2020, revealing their spatiotemporal distribution differences over time. The environmental Kuznets curve (EKC) is used to analyze the interrelationship between the two, with the purpose of filling the gap in current research. The main results are as follows: (1) From 1990 to 2020, ESSV in Guangxi increased significantly and reached its highest value in 2020. Under the four scenarios, ESSV increased significantly in Scenarios 2 and 4. Spatially, high ESSV was mainly distributed in some cities in central, southern, western and northeastern Guangxi. (2) The index of human disturbance in Guangxi continued to increase during the study period, with a high level of human disturbance in the central urban area and a low level of human disturbance in the peripheral areas, which were distributed in a radial pattern. (3) According to the EKC, the relationship between ESSV and human disturbance in Guangxi followed an inverted N-shaped curve. In addition, after 2010, the coupling and coordination level was dominated by “slightly balanced development”, and the area of “ESSV significantly lagged” gradually increased. This study provides a new perspective for understanding ESSV and its relationship with human disturbances, and provides an important reference for the sustainable management of ecosystems and the formulation of ecological conservation policies.

Historicizing Latin American urban politics and governments

ABSTRACT Existing studies about the politics of southern cities, particularly Latin American cities, need to pay more attention to the political institutions behind urban governance. These institutions, additionally, were not created by design but are a product of intertwined historical processes. This article analyzes the main features and transformations of Latin American local governments, their politics, and governance, looked at from the angle of their historical formation. Mobilizing arguments from urban studies and political science usually developed apart, I start with the legacies of two intertwined historical processes—urbanization(s) and state formation(s)—to later observe their recent transformations since the recent return(s) to democracy. The reconstruction of these intertwined historical trajectories and of the effects of the present democratic period help to jointly explain the most important features of the politics of local governments in Latin America that influence their governance and actions—capacities, political grammars, actors, and coalitions—as well as their recent transformations.

The impact of national land supervision system on urban low-carbon transformation: evidence from China

The land system is a crucial factor influencing urban low-carbon sustainable development. However, previous research has paid little attention to the effects and mechanisms of the national land supervision system (NLSS) on urban low-carbon transformation (ULCT). This study uses China’s routine land inspection as a quasi-natural experiment and examines the impact of NLSS on ULCT using panel data from 283 Chinese cities between 2005 and 2016. The study finds that NLSS significantly promotes ULCT, with a series of robustness checks supporting this conclusion, showing a 1.95% improvement in carbon emission performance in cities under supervision. NLSS mainly facilitates ULCT by improving land use efficiency, upgrading the structural of the service sector, and promoting technological progress. Compared to eastern cities, southern cities, large cities, and non-resource-based cities, NLSS more effectively promotes low-carbon transformation in central and western, northern, small- and medium-sized, and resource-based cities. Additionally, in contrast to cities with high environmental awareness, high marketization levels, high financial development levels, and high fiscal pressure, NLSS more strongly promotes ULCT in cities with lower levels of these factors. Furthermore, NLSS exhibits a significant positive spatial spillover effect in promoting ULCT. In advancing ULCT, NLSS can be synergized with smart city pilot policies and innovative city pilot policies but has not shown synergies with low-carbon city pilot policies.

Teachers’ Interaction with Prescribed Teaching Materials: Evaluation, Adaptation and Exploitation

In recent years, material development in English language teaching has received growing attention, yet the interaction between English language teachers and prescribed teaching materials remains an under-researched area. This study aims to address this issue and contribute to the understanding of teachers’ agency in their interactions with prescribed textbooks. The study addresses this gap by exploring how five high school English teachers in two major cities in southern and southwestern China interact with prescribed textbooks within the curriculum policy context. Through in-depth semi-structured interviews and documentary analysis, the study investigates teachers’ evaluation, adaptation, and exploitation of materials, revealing that while teachers exercise agency in material development, both textbook structure and external factors contribute to the deprofessionalisation of teachers. The findings underscore the complex relationship between a standardised curriculum and teachers’ context-sensitive practices, highlighting the need for flexible textbook designs and more supportive administrative practices to better facilitate teacher agency in classroom material use.

Exploring the relationship between digital infrastructure and carbon emission efficiency: New insights from the resource curse and green technology innovation in China

Resource-rich regions can fall prey to the resource curse, leading to a decline in carbon emissions efficiency (CEE). But amid this challenge, building digital infrastructure offers an opportunity to find solutions that will pave the way for sustainable development. An indicator evaluation system was constructed to measure the level of digital infrastructure (DI) using panel data for 275 Chinese cities from 2010 to 2020. The impact of DI on CEE is validated using several econometric models. As an innovation, the time lag effect and spatial spillover effects are considered in the analysis. The study found that DI significantly improves CEE, and this effect is more effective in central and resource-based cities, but only significant in southern cities, cities with high levels of marketization, and cities with high levels of human capital. Reducing the resource curse and increasing green technological innovation are important transmission pathways, which are considered to be the key role of DI. Further, the third period of lagged DI has the most significant effect, and there is a positive spatial spillover effect of DI on the CEE of neighboring cities, which is most prominent around 600 km. Policymakers are advised to improve the level of construction of DI, focus on digital management, and utilize the role of DI at the optimal time and distance.

Understanding Polycyclic Aromatic Hydrocarbon Accumulation in Road Dust of a Tropical Megacity in Southern Vietnam: Implications on Environmental Management

This study investigated the characteristics of 23 PAHs in road dust from various areas in Ho Chi Minh City (HCMC), focusing on spatial distribution, pollution levels, human health risks, and source apportionment. PAH levels in urban samples (residential and industrial sites) ranged from 208 to 7665 (μg/kg), significantly higher than background levels (135±42.2μg/kg). A west>east gradient in PAH distribution, particularly in crowded traffic intersections, suggested traffic activities as a major source. Pollution load indices indicated moderate to very high pollution in most urban sites. Incremental lifetime cancer risk assessments showed moderate to high risks, especially for children. Statistical analyses and diagnostic ratios identified vehicular emissions as the primary PAH sources, with Positive Matrix Factorization analysis attributing 46.6% to gasoline vehicles, 21.9% to diesel vehicles and petroleum evaporation, 18.3% to tar oil, and 10.2% to coal burning. This study fills a significant information gap on PAHs in road dust, which has not been previously reported in southern Vietnam, specifically in HCMC-a dynamic and rapidly developing city in Southeast Asia. The findings highlight the need for synchronized management and technical solutions to mitigate PAH risks in road dust, contributing valuable knowledge on PAH accumulation in a major southern city of Vietnam.

Investigation of Chinese-Style Greenhouse Usage Across Europe

Chinese-style greenhouses (CSGs), characterized by a distinct geometric shape compared to traditional greenhouses, are extensively utilized in China. In this study, this type of greenhouse was modeled using TRNSYS software version 18 and experimentally validated. The model can transiently determine the indoor conditions of the greenhouse and the requirement for additional heating. It calculates the heat loss due to plant evapotranspiration as well as all the heat gains and losses from the surfaces. The application of this greenhouse has been investigated from the southernmost to the northernmost regions of Europe. For this purpose, cities located at different latitudes (between 32.63° N and 69.65° N) were entered into the model, and the results were obtained and compared. The analysis conducted over the entire year demonstrated that the CSG indoor temperature is more dependent on solar energy during the day and on outdoor temperature at night. The two southernmost cities in our survey, Funchal, Portugal (32.63° N) and Luqa, Malta (35.83° N), had no winter heating requirement. The thermal covering was sufficient to minimize night heat loss and maintain a suitable indoor temperature. In northern cities, the heating requirement was relatively high due to the lower outdoor temperature and solar radiation. Consequently, the duration of the heating season increases towards the north. In the northernmost city, Tromso, Norway (69.65° N), the heating season was determined to last 12 months. In the absence of solar energy, the transparent surface of the greenhouse is covered with thermal insulation to prevent heat loss. It has been shown that with the appropriate selection of this thermal covering, which is controlled based on the presence of instantaneous solar energy, up to 80% savings can be achieved from additional heating in southern cities. In the north, this rate can be increased up to a maximum of 70% by increasing the thermal covering thickness.

A multi-index comprehensive evaluation method for assessing the water use balance between economic society and ecology considering efficiency-development-health-harmony.

Quantitative assessment of the water use balance between economic society and ecology (EEWB) is the basis for coordinating the competitive relationship of water use between human activity and ecological requirements and. It is of great significance for optimizing the water resources carrying capacity and achieving a healthy regional water balance. Based on the concept of harmonious balance, this paper puts forward the definition and connotation of EEWB regarding the competition in water use between economic society and ecology. And, a novel framework for assessing the EEWB is proposed. It has four aspects relating to water resources, economic society, ecology, and human-water relationship. Linked to these aspects the Data Envelopment Analysis (DEA) technique, Water Ecological Footprint (WEF) model, InVEST model and indicators system of human-water relationship are used to establish a water resources efficiency index (IEEWB-W), economic society high-quality development index (IEEWB-ES), ecology health index (IEEWB-E), harmony index of human-water relationship (IEEWB-H). The four indices were then integrated into the water use balance between economic society and ecology index (IEEWB) with Euclidean distance, thus forming the EEWB quantification method system. Finally, the temporal and spatial characteristics of EEWB during 2010-2022 was diagnosed in Henan Province and cities of China. Results reveal that: (1) The water resources utilization efficiency exhibit a changing trend of initial decrease followed by subsequent increase; (2) Southern cities in Henan Province have a higher economic society development level compared to northern cities; (3) IEEWB-E in Henan Province is below 0.60, indicating that the regional ecology health remains consistently vulnerable; (4) IEEWB-H in Henan Province shows an increasing trend, indicating that a gradual improvement and overall upward development in the human-water relationship; (5) IEEWB multi-year average was within [0.53, 0.65] in Henan Province, indicating a state of Proximity imbalance. The low level of ecological health is the primary influencing factor. These findings will contribute to a better understanding of the water use balance between economic society and ecology and provide scientific reference for achieving a healthy regional water balance.

The effects of extreme temperatures on carbon total factor productivity: Evidence from China

Climate change poses a severe threat to the low-carbon and high-quality development of Chinese cities. This paper uses panel data from 2007 to 2019 for Chinese cities, which covers the transition of China's economy from high-speed growth to high-quality development. Then, this paper investigates the causal effects and mechanisms of extreme temperatures on carbon total factor productivity (CTFP). There are four main findings. First, CTFP calculated by biennial non-radial Luenberger productivity index grows by 3%, which comes from technological advances rather than efficiency gains. Second, both extremely high and low temperatures significantly reduce CTFP, and this negative effect is persistent, especially in poor and southern cities. Third, this negative effect comes from the decline in efficiency change rather than technology change and can also be explained by a decline in the productivity and efficiency of the desired output. Fourth, the forecasted outcomes for the future scenarios under the Shared Socioeconomic Pathways 1 (SSP1) and 5 (SSP5) indicate a persistent escalation in the adverse effects of extreme high temperatures. The research provides a new perspective for China to cope with climate change on low-carbon development and provides a reference for other developing countries.

Spatiotemporal Characterization and Driving Factors of Fine Particulate Matter and Its Chemical Components in the Huaihe River Basin

According to the data sets of fine particulate matter （PM2.5） and its components in 35 cities in the Huaihe River Basin from 2015 to 2021, the temporal and spatial distribution patterns of pollutants were analyzed. The influence of meteorological factors on PM2.5 concentrations was examined using a random forest model. The original series of PM2.5, sulfate （SO42-）, nitrate （NO3-）, ammonium salt （NH4+）, organic matter （OM）, and black carbon （BC） were rebuilt using KZ （Kolmogorov-Zurbenko） filtering and multiple linear regression （MLR） to quantify the effects of meteorological conditions. The results demonstrated that from 2015 to 2021, the declining rates of PM2.5, SO42-, NO3-, NH4+, OM, and BC in the Huaihe River Basin were 4.71, 0.99, 1.05, 0.77, 1.01, and 0.19 μg·（m3·a）-1, respectively. The high mass concentrations of PM2.5 and its components were concentrated in the central and western regions of the HRB, whereas those in coastal and southern cities were lower. The variance contributions of the short-term, seasonal, and long-term components of PM2.5 to the original PM2.5 sequences in 35 cities were 51.6%, 35.9%, and 7.0%, respectively. The PM2.5 in coastal cities were more affected by the short-term components. The meteorological conditions were unfavorable for PM2.5 reduction in the HRB from 2015 to 2018, whereas the meteorological conditions supported the PM2.5 decrease from 2019 to 2021. From 2015 to 2021, the contribution rates of meteorological conditions to the long-term component reductions of PM2.5, SO42-, NO3-, NH4+, OM, and BC were 28.3%, 29.1%, 31.0%, 29.3%, 27.8%, and 28.6%, respectively. The contribution rates of meteorological conditions to the long-term PM2.5 reduction were 43.4%, 25.6%, 25.5%, and 20.6% in the HRB cities in Anhui, Shandong, Jiangsu, and Henan Provinces, respectively. With the decrease in PM2.5 concentration in the HRB, the sulfur oxidation rate （SOR） increased significantly, while the nitrogen oxide oxidation rate （NOR） changed little.

Urban bryophyte floras of Spain: a meta-analysis

ABSTRACT Introduction Bryophytes constitute an important part of the unmanaged plant diversity of urban areas. They represent, directly and indirectly, an important food, shelter and microhabitat-engineering resource allowing the establishment of other organisms, thereby increasing the biodiversity of urban areas. However, their contribution to urban biodiversity is generally overlooked and poorly understood. Methods In this study, we compared pre-existing data from 23 Spanish urban bryophyte floras and used taxon accumulation curves and ordination analyses to reveal emergent patterns related to urban biodiversity in Spain. Key results The compilation of these 23 floras revealed 286 bryophytes represented in urban areas in peninsular Spain and the Balearic Islands, including 2.80% and 3.50% of taxa considered under some threat category at the European and Iberian scales, respectively. Taxon richness and diversity varied greatly across cities and were strongly affected by climatic characteristics and extension of the studied cities. Ordination analyses showed an alignment of the different floras with the geographical location of the cities. Eurosiberian (Atlantic) and eastern and southern cities showed a higher taxon richness compared with cities from central Spain, which showed taxon assemblies comprising the commonest and widespread taxa. We also found that taxon richness was influenced by methodological factors (i.e. sampling intensity and the time the study was done). Conclusions Our study results suggest a need for adequate sampling of habitat heterogeneity within the urban landscape and point to the contribution of bryological knowledge to our understanding of the biodiversity of urban areas.

A comprehensive evaluation of the atmospheric impacts and health risks of cooking fumes from different cuisines

Pollutants emitted by catering enterprises pose a significant threat to the environment and public health. In this study, based on a systematic analysis of volatile organic compound (VOC) emission characteristics of different cuisines, the contribution of cooking emissions from catering enterprises to the PM2.5 and O3 concentrations in the atmosphere was evaluated using generation potential calculations and WRF-CAMx simulations. The health exposure risks of VOCs in kitchen breathing areas and those of PM2.5 and O3 contributed by the catering enterprises were evaluated. The generation potential calculation results showed that the catering enterprises exhibit 2.21–5.00 gO3/gVOCs of ozone formation potential (OFP) and 0.07–0.21 gSOA/gVOCs of secondary organic aerosol production potential (SOAP). The WRF-CAMx simulation results indicated that cooking emissions from catering enterprises contribute 0.36–1.91 μg/m3 and 0.05–0.21 μg/m3 to PM2.5 and maximum daily 8-h average (MDA8) concentrations of O3. The health exposure risks of PM2.5 and O3 were higher in catering enterprises in southern cities than in northern cities and were higher in urban areas than in suburban areas. The average hazardous VOCs (HVOCs) concentrations ranged from 53 ± 16 to 357 ± 31 μg/m3 in kitchen breathing areas. Acrolein was the primary contributor to the hazard index (HI) of all VOC species, accounting for 50.9%–99.5%. The total incremental lifetime carcinogenic risk (ILCR) of all cuisines exceeded the acceptable thresholds of 1.00 × 10−6. These findings provide insights that can aid in the formation and implementation of pollutant mitigation strategies in the catering industry.

Urban Sprawl and Imbalance between Supply and Demand of Ecosystem Services: Evidence from China’s Yangtze River Delta Urban Agglomerations

The contradiction between ecological resource protection and urban sprawl in urban agglomeration areas is becoming more and more prominent, facing a serious imbalance between the supply and demand of ecosystem services. To analyze the impact of urban agglomeration expansion on regional ecosystem services, based on multi-source data, an assessment model of supply and demand of ecosystem services for water conservation, carbon sequestration, soil conservation and crop production was constructed. With the help of value transformation model and spatial analysis method, this paper explores the risk of ecosystem service supply and demand imbalance faced by the Yangtze River Delta urban agglomeration in the process of expansion. This study found that the supply capacity of ecosystem services in the YRDUA has continued to decline at the spatial pixel scale; ecosystem service value deficits are a common problem in the YRDUA, with cities around Taihu Lake, such as Shanghai and Suzhou, being the most serious; the value surplus areas are concentrated in the southern cities, such as Xuancheng and Chizhou, but the balance between the supply of and demand for ecosystem services in these cities is also facing a challenge as the cities are expanding. This study analyzed the spatial pattern changes in the Yangtze River Delta region in the context of urban sprawl from the perspective of ecosystem service supply and demand, which helps to clarify the changing ecosystem service dynamics of the region and guide the formulation of urban planning policies and to achieve a balance between ecological supply and demand as well as sustainable development.

Socialization of Elementary School PJOK Teachers in the Southern City of Cimahi through Pickleball Sports

The aim of carrying out this community service activity is to provide knowledge and information about new types of sports that are currently popular with many people in all circles, and one of them is introducing the sport of Pickleball. Some of the implementation methods for this activity are delivery using lecture, discussion and question and answer methods, as well as direct demonstrations or practice. This research was carried out at Melong Mandiri 3 Elementary School, Cimahi City, involving one regional branch of South Cimahi City with a total of 7 schools involved. The results of this research show that what is proposed in this community service activity plan can be implemented well and fulfilled. From the results of the implementation of this activity, it was found that the majority of PJOK teachers in the South Cimahi area were still unfamiliar with the sport of pickleball because, from the test results using questions, an average of 85.7% of the 15 people present were not familiar with the sport of pickleball. Therefore, after being given this socialization material, the participants had quite a high enthusiasm for learning about the sport of pickleball.

Epidemiological characteristics and transmission dynamics of dengue fever in China

China has experienced successive waves of dengue epidemics over the past decade. Nationwide data on 95,339 dengue cases, 89 surveillance sites for mosquito density and population mobility between 337 cities during 2013-20 were extracted. Weekly dengue time series including time trends and harmonic terms were fitted using seasonal regression models, and the amplitude and peak timing of the annual and semiannual cycles were estimated. A data-driven model-inference approach was used to simulate the epidemic at city-scale and estimate time-evolving epidemiological parameters. We found that the geographical distribution of dengue cases was expanding, and the main imported areas as well as external sources of imported cases changed. Dengue cases were predominantly concentrated in southern China and it exhibited an annual peak of activity, typically peaking in September. The annual amplitude of dengue epidemic varied with latitude (F = 19.62, P = 0.0001), mainly characterizing by large in southern cities and small in northern cities. The effective reproduction number Reff across cities is commonly greater than 1 in several specific months from July to November, further confirming the seasonal fluctuations and spatial heterogeneity of dengue epidemics. The results of this national study help to better informing interventions for future dengue epidemics in China.

Research on characteristics and influencing factors of road dust emission in a southern city in China.

One of the primary causes of urban atmospheric particulate matter, which is harmful to human health in addition to affecting air quality and atmospheric visibility, is road dust. This study used online monitoring equipment to examine the characteristics of road dust emissions, the effects of temperature, humidity, and wind speed on road dust, as well as the correlation between road and high-space particulate matter concentrations. A section of a real road in Jinhua City, South China, was chosen for the study. The findings demonstrate that the concentration of road dust particles has a very clear bimodal single-valley distribution throughout the day, peaking between 8:00 and 11:00 and 19:00 and 21:00 and troughing between 14:00 and 16:00. Throughout the year, there is a noticeable seasonal change in the concentration of road dust particles, with the highest concentration in the winter and the lowest in the summer. Simultaneously, it has been discovered that temperature and wind speed have the most effects on particle concentration. The concentration of road dust particles reduces with increasing temperature and wind speed. The particle concentrations of road particles and those from urban environmental monitoring stations have a strong correlation, although the trend in the former is not entirely consistent, and the changes in the former occur approximately 1 h after the changes in the latter.

Specific persistent symptoms of COVID-19 and associations with reinfection: a community-based survey study in southern China.

Surveillance remains fundamental to understanding the changes in epidemiological patterns regarding post-COVID conditions and reinfections. Persistent symptoms and reinfection in previously infected individuals are increasing being reported in many countries, but their associations among general populations were seldomly reported. Understanding the association with persistent symptoms of COVID-19 reinfection is essential to develop strategies to mitigate the long-term health and socio-economic impacts of the post-COVID conditions. This study aimed to investigate the incidence of COVID-19 persistent symptoms among previously infected Chinese community residents and explore associations of specific COVID-19 persistent symptoms with reinfection and other factors. A community-based survey was conducted in a southern city of China with about 20 million residents from August 3 to 24, 2023. Face-to-face questionnaires were distributed to a total of 1,485 residents to collect their information about COVID-19 infection, reinfection, specific ongoing persistent symptoms, and other COVID-19 related information. Multivariable logistic regression analysis was used to examine the association between specific persistent symptoms and reinfection of COVID-19, along with age, gender, and educational level. Of the 1,485 participants, 1,089 (73.3%) reported they had been infected with COVID-19. Among them, 89.1% reported having ongoing persistent symptoms and 14.2% reported had two or more times of infection. About 20% participants were infected 1 year or more since their initial infection. Fatigue, cough, and headaches were the top 3 symptoms being reported. Participants with reinfection were associated with a higher probability of reporting headaches (OR: 1.54, 95% CI: 1.06-2.25), loss of or change in smell and/or taste (OR: 1.90, 95% CI: 1.27-2.83), impaired sleep (OR: 1.55, 95% CI: 1.02-2.35), and brain fog (OR: 1.76, 95% CI: 1.12-2.76). Participants aged 45 and above and who had a bachelor's or higher degree were more likely to report chest tightness or shortness of breath, impaired sleep, and brain fog. During the post-emergency period of COVID-19 pandemic, the incidence of ongoing persistent symptoms among Chinese residents remains high. Individuals whose initial infection was longer than 1 year have the highest probability of reporting having multiple symptoms. Reinfection may increase the risk of reporting headaches, loss of or change in smell and/or taste, impaired sleep, and brain fog. It is important to maintain routine syndromic surveillance among previously infected people and provide recommendations for clinical management of individuals with multiple ongoing symptoms.

Overlooked Trace Molecules in Organic Aerosol Revealed by Gas Chromatography-Orbitrap Mass Spectrometry.

Molecular characterization of organic aerosol (OA) is crucial for understanding its sources and atmospheric processes. However, the chemical components of OA remain not well constrained. This study used gas chromatography-Orbitrap mass spectrometry (GC-Orbitrap MS) and GC-Quadrupole MS (GC-qMS) to investigate the organic composition in PM2.5 from Xi'an, Northwest China. GC-Orbitrap MS identified 335 organic tracers, including overlooked isomers and low-concentration molecules, approximately 1.6 times more than GC-qMS. The "molecular corridor" assessment shows the superior capability of GC-Orbitrap MS in identifying an expansive range of compounds with higher volatility and oxidation states, such as furanoses/pyranoses, di/hydroxy/ketonic acids, di/poly alcohols, aldehydes/ketones, and amines/amides. Seasonal variations in OA composition reflect diverse sources: increased di/poly alcohols in winter are derived from indoor emissions, furanoses/pyranoses and heterocyclics in spring and summer might be from biogenic emissions and secondary formation, and amides in autumn are probably from biomass burning. Integrating partial least squares discriminant analysis (PLS-DA) and potential source contribution function (PSCF) models, the source similarities and differences are further elucidated, highlighting the role of local emissions and transport from southern cities. This study offers new insights into the OA composition aided by the high mass resolution and sensitivity of GC-Orbitrap MS.

Does environmental regulation matter for healthcare utilisation in China? An interrupted time series study.

In recent years, China has implemented a series of environmental regulation policies to improve air quality, but the health effects of these policy changes need to be accurately clarified and quantified. The objective of this study was to empirically examine the effects of levying construction dust pollution fees on healthcare utilisation in a southern city of China. The study used a unique administrative insurance claim dataset from the city's Urban Employee Basic Medical Insurance scheme between 2013 and 2015. The sample included 69,961 enrolees. An interrupted time series design was employed to investigate whether and how the healthcare utilisation of enrolees changed after the policy change. The results showed that this environmental regulation policy did not affect the inpatient utilisation of enrolees but did negatively impact outpatient utilisation. In addition, outpatient utilisation of chronic disease coverage decreased for patients with chronic diseases, including diabetes and hypertension. This study provides evidence that enhancing environmental regulations helps reduce medical costs, which can benefit China and other developing countries to improve environmental quality and promote public health.