Urban Environment Research Articles

A novel stereotyped phase change material with a low leakage rate for new energy storage building applications

Phase change materials (PCM) have been widely studied in the field of building energy storage. However, industrial grade high latent heat phase change paraffin (PW) has the problem of high melting point and easy leakage, and at the same time, it is necessary to absorb municipal solid waste on a large scale and reduce the damage of waste cellular concrete (WCC) to the urban ecological environment. Using binary paraffin wax (BP) prepared by hot fusion of solid paraffin (SP) and liquid paraffin (LP) as composite phase change materials, polypropylene (PP) and porous material WCC as support materials, a new WCC/PP/BP stereotyped phase change material (FCPCM) with low leakage rate and good stability was prepared by melt blending method and vacuum adsorption method, to meet the energy storage needs of buildings. The chemical compatibility, thermal performance and morphological stability of the prepared FCPCM were tested, and the heat storage/release performance test experiments were carried out to explore the thermal performance of the prepared energy storage concrete. The results show that the Encapsulated WCC/PP/BP has no new substance and good chemical compatibility. The results of scanning electron microscope (SEM) and mercury injection instrument (MIP) show that WCC has good adsorption properties for PP/BP. The melting phase change temperature increases by 14.08%, the latent heat of phase change decreases by 42.94%, and the initial phase change thermal properties are still maintained after several phases of phase change. It can maintain a stable form at 150℃. The 24 h leakage rate remained below 1%, which was nearly 44% lower than that of FCPCM with PP as the support material. Thermogravimetric curve (TGA) shows that the thermal stability of encapsulated FCPCM increases by 25.59%. In addition, the thermal performance test of energy storage concrete shows that compared with traditional concrete, energy storage concrete has greater heat storage density and stronger temperature control ability, which can effectively realize building energy saving.

Construction and optimization of Green Infrastructure Network in mountainous cities: a case study of Fuzhou, China

Green infrastructure networks enhance the protection and improvement of urban ecological environments, augment the efficiency and quality of ecosystem services, and furnish residents with healthier and more comfortable living conditions. Although previous research has investigated the construction or optimization methods of green infrastructure networks, these studies have been relatively isolated and lacking in case studies for mountainous cities. In the development of green infrastructure, mountainous cities must specifically consider the impact of terrain on network construction. Taking Fuzhou, a mountainous city in China, as an example, this study constructs and optimizes the green infrastructure network by employing morphological spatial pattern analysis, connectivity analysis, the Minimum Cumulative Resistance model, and circuit theory. These methodologies increase the connectivity of the Green Infrastructure within the study area, thereby promoting the health of the local ecosystem and creating conducive circumstances for the city’s sustainable development. The findings reveal that: (1) Green infrastructure in Fuzhou takes up 5366.38 ha, constituting 21.76% of the study area, primarily situated in the northwest and south; (2) Fuzhou’s Green Infrastructure network comprises 10 hubs and 17 corridors with a hub area of 1306.98 ha, predominantly distributed in the mountains encircling the city, including Meifeng Mountain, Gaogai Mountain, and Qingliang Mountain; (3) Based on optimization, the circuit centrality index categorizes hub importance into three protection levels, pinpointing nine crucial protected areas in the corridors and 680 areas requiring enhancement, including 68 areas for first-level improvement, 149 areas for second-level improvement, and 463 areas for third-level improvement. This research offers a methodological reference for constructing and optimizing green infrastructure networks in mountainous cities, providing both theoretical and practical foundations for optimizing green infrastructure networks in Fuzhou City.

Unfolding the entangled geosemiotics of technologically-mediated gated communities: Mountain View’s (2021) advertisement as a case study

Gated Communities (GCs), as residential enclaves in urban and suburban environments that offer exclusive housing and a multitude of onsite amenities, are burgeoning in many fast-growing Egyptian cities. In the past few years, several upscale Egyptian GCs have received unequivocal attention in high-profile TV advertisements and campaigns which package and technologically mediate social spaces overlaid with aesthetics of unique architectural character, distinctive leisure amenities, social exclusiveness, and prestigious lifestyles. Set against this backdrop, this paper takes up a postphenomenological-geosemiotic approach toward the examination of the affects of elitism that transpire in one upmarket urban enclave’s advertisement, namely Mountain View. Arguably, in the filmic narrative of the promoted social spaces, the technological mediation and intentionality of the camera shot scale modulate multi-sensory and multi-spatio-temporal relationships between viewers and the GC lifeworld/residents that are worthy of scrutiny. Key findings include how POV camera shots are employed and appropriated to mitigate (and mediate) the representation of transnational elite semiotic landscapes and the pertinent affective intersubjectivities of doing eliteness. The systematic analysis of MV’s semiotic aggregate unravels an affective aggregate that is, in essence, a concrete instantiation of Foucault’s notions of heterotopia and (post)-panopticism.

Assessment of genotoxicity of air pollution in urban areas using an integrated model of passive biomonitoring

Atmospheric pollution is a major public health issue and has become increasingly critical for human health. Urban atmospheric pollution is typically assessed through physicochemical indicators aligned with environmental legislation parameters, providing data on air quality levels. While the effects of pollution on sensitive organisms serve as a warning for public health decision-makers, there remains a need to explore the interpretation of environmental data on pollutants. The use of species adapted to urban environments as sentinels enables continuous and integrated monitoring of environmental pollution implications on biological systems. In this study, we investigated the use of the plant species Tradescantia pallida as a biomonitor to evaluate the genotoxic effects of atmospheric pollution under diverse vehicular traffic conditions. T. pallida was strategically planted at the leading urban intersections in Uberlândia, Brazil. During COVID-19 pandemic lockdowns, we compared indicators such as physical, biological, and traffic data at different intersections in residential and commercial zones. The reduction in vehicular traffic highlighted the sensitivity of plant species to changes in air and soil pollutants. T. pallida showed bioaccumulation of heavy metals Cd and Cr in monitored areas with higher traffic levels. Additionally, we established a multiple linear regression model to estimate genotoxicity using the micronucleus test, with chromium concentration in the soil (X1) and particulate matter (PM) in the atmosphere (X2) identified as the primary independent variables. Our findings provide a comprehensive portrait of the impact of vehicular traffic changes on PM and offer valuable insights for refining parameters and models of Environmental Health Surveillance.

No such thing as peacetime: Notes on Gaza, Hannah Arendt and cultural studies

This comment piece, prompted by the ongoing conflict in Gaza and the terrible toll of lives of Gazan people following the Hamas attack on Israel on 7 October 2023, argues that the field of cultural studies has its origins in a notion of post-war peacetime and that this has created a vocabulary deficit in regard to war, genocide and state violence. Paul Gilroy and Stuart Hall have confronted patterns of violence in regard to the urban environment and the policing of Black youth as well as the escalation in day-to-day authoritarianism and the rise of the right. There is a strong case to be made however for the field of cultural studies to more fully draw on political philosophy including Middle East scholarship to engage more directly with the politics of occupation, settler colonialism, neo-nationalism and the far right.

Towards Sustainable Urban Futures: Integrating a Novel Grey Multi-Criteria Decision Making Model for Optimal Pedestrian Walkway Site Selection

Today, urban development faces complex global challenges that require new approaches to influence its practices and policies. By prioritizing sustainability, mobility, and community resilience, we are moving towards a holistic approach that protects the well-being of residents and the environment. In this dynamic urban design environment, finding ways to identify pedestrian-friendly spaces and create safe, efficient, and sustainable urban environments is a major challenge, and it requires research that seeks to optimize this choice, especially in terms of integrating numerical modeling methods and a wide range of measurement tasks. This research is concerned with optimizing pedestrian accessibility, which directly contributes to reducing environmental impact, improving non-motorized transport, and reducing traffic congestion. It integrates a novel, mixed multi-criteria decision-making (MCDM) model that benefits from the use of Grey’s theory. This research’s purpose goes beyond addressing cities’ immediate challenges; it seeks to contribute to a broader understanding of sustainable urban planning. This study represents a pioneering effort to identify the challenges of optimal site selection for pedestrian walkways. By using a multi-criteria decision-making approach based on mathematical modelling and facility engineering, this effort addresses gaps in the current understanding of site selection criteria and aims to lead a paradigm shift toward a sustainable, efficient, and inclusive urban environment. The results show that the updated RANCOM-PIV greyscale is quite robust and reliable, when comparing the final results of the PIV greyscale and the MARCOS greyscale.

Histological and Physiological Study of the Effects of Biostimulants and Plant Growth Stimulants in Viburnum opulus 'Roseum'.

Biostimulants and other plant growth promoters can provide an effective solution to the challenge of urbanisation and climate change. Viburnum opulus 'Roseum' is a globally popular deciduous shrub species that can be made more resistant to urban influences by using natural growth-promoting substances. In our study, we investigated the effects of growth promoters Kelpak®, Bistep and Yeald Plus on the species, both histologically and physiologically (proline stress hormone measurement). Our measurements were complemented using the analysis of rhizosphere alkaline phosphatase, β-glucosidase and β-glucosaminidase enzymes, to obtain a more complete picture of the combined effect of biostimulants and species. We found that the Bistep biostimulant had an outstanding effect on the leaf tissue culture results of the variety. The transpiration and evapotranspiration findings also confirmed the efficacy of biostimulants. In the case of POD activity and rhizosphere enzyme measurements, Bistep and Yeald Plus obtained statistically higher values than the control group. Kelpak produced better results than the control group in several measurements (alkaline phosphatase levels; evapotranspiration results), but in other cases it resulted in lower values than the control treatment. The use of Bistep and Yeald Plus can greatly assist growers in the cultivation of V. opulus 'Roseum' in an urban environment.

Unraveling the Potential of Attentive Bi-LSTM for Accurate Obesity Prognosis: Advancing Public Health towards Sustainable Cities.

The global prevalence of obesity presents a pressing challenge to public health and healthcare systems, necessitating accurate prediction and understanding for effective prevention and management strategies. This article addresses the need for improved obesity prediction models by conducting a comprehensive analysis of existing machine learning (ML) and deep learning (DL) approaches. This study introduces a novel hybrid model, Attention-based Bi-LSTM (ABi-LSTM), which integrates attention mechanisms with bidirectional Long Short-Term Memory (Bi-LSTM) networks to enhance interpretability and performance in obesity prediction. Our study fills a crucial gap by bridging healthcare and urban planning domains, offering insights into data-driven approaches to promote healthier living within urban environments. The proposed ABi-LSTM model demonstrates exceptional performance, achieving a remarkable accuracy of 96.5% in predicting obesity levels. Comparative analysis showcases its superiority over conventional approaches, with superior precision, recall, and overall classification balance. This study highlights significant advancements in predictive accuracy and positions the ABi-LSTM model as a pioneering solution for accurate obesity prognosis. The implications extend beyond healthcare, offering a precise tool to address the global obesity epidemic and foster sustainable development in smart cities.

Drive-by Environmental Sensing Strategy to Reach Optimal and Continuous Spatio-Temporal Coverage Using Local Transit Network

Monitoring environmental features, such as air pollution, carbon dioxide emissions, noise, and heat, gives cities key data-driven insights to advise sustainable policies and city design. However, given the high variability of the environmental data, achieving good spatio-temporal resolution and coverage remains a major challenge. Even in well-monitored cities, such as Amsterdam, environmental sensors are usually placed in very few fixed locations, implying limited spatial coverage and an inability to adapt to changes in the urban environment. As cities evolve, they experience shifts in pollution sources, and fixed sensors might not adequately capture these changes without a costly and time-consuming reconfiguration process. To monitor the environmental qualities of Amsterdam’s roads, we present a “drive-by” sensing solution for a structured network of vehicles, meaning that sensors are designed to be deployed on buses and tramways, the trajectories and schedules of which are known. We propose a deployment strategy that combines the available fleets to reach optimal spatio-temporal coverage for different environmental features. For example, by optimizing the deployment of sensors on public transit vehicles, our proposal significantly enhances the monitoring of pollution-sensitive areas in Amsterdam. Depending on the desired spatio-temporal granularity and noting that one vehicle only hosts one sensor, the required number of sensors to be deployed on the structured network varies between 43 and 142, with the latter achieving the finest possible resolution.

#842 Validation of the excessive salt intake screening questionnaire in CKD patients

Abstract Background and Aims Excessive salt intake is implicated in the progression of hypertension, chronic kidney disease (CKD), diabetic nephropathy, cardiovascular diseases, cerebrovascular diseases, and increased mortality. In Japan, average salt consumption surpasses the levels recommended by national guidelines and the WHO. However, individuals seldom have the chance to gauge their salt intake accurately. This study aimed to validate a screening tool initially developed by Sasaki et al. to identify individuals with excessive salt intake using health check-up data from Asahi City, Chiba Prefecture, Japan. Method This study was conducted as a part of the Cities Changing Diabetes (CCD). CCD is Novo Nordisk's commitment to drive action against type 2 diabetes and obesity in cities globally. It is a partnership program to accelerate the prevention of diabetes and obesity by addressing the systemic change in urban environments. Participants of this study were drawn from specific health examinations in Asahi City. Consent was obtained, and dialysis patients were excluded. Spot urine samples were analyzed for sodium and creatinine to estimate daily salt intake via Tanaka's formula. The screening tool incorporated risk factors such as age, gender, Body Mass Index (obesity), hypertension (use of antihypertensive drugs), frequency of soup intake, saltiness of home-cooked meals compared to restaurants, efforts to reduce salt intake, and frequency of dining out. The primary outcome was excessive salt intake, defined as an intake exceeding one standard deviation above the mean. Discrimination was assessed using the Area Under the Curve (AUC), while calibration was evaluated with a calibration plot and the Hosmer-Lemeshow test. Results Of the 1532 CKD participants, the mean age was 76.3 years, with males comprising 46%. The average daily salt intake was 9.3 g (SD: 2.39), and the estimated Glomerular Filtration Rate (GFR) was 50.6 ml/min/1.73 m² (SD: 14.5). The distribution of CKD stages included 1198 stage 3a, 285 stage 3b, 43 stage 4, and 5 stage 5 patients. The AUC of screening tool was 0.65 (95% CI: 0.61 to 0.69), and its calibration slope (with an intercept) was 0.98 (95% CI: 0.72 to 1.25). The Hosmer-Lemeshow test yielded a p-value of 0.626. Conclusion The predictive capability of the existing model for excessive salt intake was limited in the CKD population, which may suggest a need for a screening method distinct from that used in the general population. Factors such as changes in sodium excretion due to reduced renal function and the effects of diuretics should also be considered when interpreting these results. Integrating this questionnaire into routine health check-ups could enhance dietary monitoring and intervention, potentially attenuating the progression of CKD and its associated complications. There remains scope for further refinement of the tool's accuracy by incorporating additional predictors.

Host weight, seasonality and anthropogenic factors contribute to parasite community differences between urban and rural foxes

Pathogens often occur at different prevalence along environmental gradients. This is of particular importance for gradients of anthropogenic impact such as rural-urban transitions presenting a changing interface between humans and wildlife. The assembly of parasite communities is affected by both the external environmental conditions and individual host characteristics. Hosts with low body weight (smaller individuals or animals with poor body condition) might be more susceptible to infection. Furthermore, parasites' mode of transmission might affect their occurrence: rural environments with better availability of intermediate hosts might favour trophic transmission, while urban environments, typically with dense definitive host populations, might favour direct transmission. We here study helminth communities (141 intestinal samples) within the red fox (Vulpes vulpes), a synanthropic host, using DNA metabarcoding of multiple marker genes. We analysed the effect of urbanisation, seasonality and host-intrinsic (weight, sex) variables on helminth communities. Helminth species richness increased in foxes with lower body weight and in winter and spring. Season and urbanisation, however, had strong effects on the community composition, i.e., on the identity of the detected species. Surprisingly, transmission in two-host life cycles (trophic transmission) was more pronounced in urban Berlin than in rural Brandenburg. This disagrees with the prevailing hypothesis that trophically transmitted helminths are less prevalent in urban areas than in rural areas. Generally, co-infestations with multiple helminths and high infection intensity are associated with lighter (younger, smaller or low body condition) animals. Both host-intrinsic traits and environmental drivers together shape parasite community composition and turnover along urban-rural gradients.

Interplay between greenspace interactions and sense of place in Seoul City

The intricate connection between urban residents and their surrounding greenspaces highlights the multifaceted relationship shaping individuals’ sense of place within urban environment. This study explores the influential relationship between greenspace interactions (GI) and the resultant greenspace sense of place (GSP) while considering four types of greenspaces (GT) as moderators. Employing partial least square-structural equation modeling (PLS-SEM), data was gathered from 400 participants, encompassing different GT within Seoul City, South Korea, to investigate the nuanced associations among psychological, physical, social, and environmental dimensions of GI and their impacts on place attachment (PA), sense of community (SoC), and utilitarian sense of place (USoP) in the GSP framework. Findings confirm a significant relationship between GI and GSP, emphasizing the role of environmental consciousness as a predominant factor influencing individuals’ overall perception on urban nature. Notably, despite conceptual expectations, the study revealed no moderation effect of different GT on the GI-GSP relationship, underscoring the universal relevance of urban greenspaces in fostering residents’ GSP. The result emphasizes the intrinsic value of urban greenspaces in shaping the preference of urban residents regarding urban nature.

Urban stormwater green infrastructure: Evaluating the public health service role of bioretention using microbial source tracking and bacterial community analyses

Bioretention cells (BRCs) control stormwater flow on-site during precipitation, reducing runoff and improving water quality through chemical, physical, and biological processes. While BRCs are effective in these aspects, they provide habitats for wildlife and may face microbial hazards from fecal shedding, posing a potential threat to human health and the nearby environment. However, limited knowledge exists regarding the ability to control microbial hazards (e.g., beyond using typical indicator bacteria) through stormwater biofiltration. Therefore, the purpose of this study is to characterize changes in the bacterial community of urban stormwater undergoing bioretention treatment, with the goal of assessing the public health implications of these green infrastructure solutions. Samples from BRC inflow and outflow in Columbus, Ohio, were collected post-heavy storms from October 2021 to March 2022. Conventional culture-based E. coli monitoring and microbial source tracking (MST) were conducted to identify major fecal contamination extent and its sources (i.e., human, canine, avian, and ruminant). Droplet digital polymerase chain reaction (ddPCR) was utilized to quantify the level of host-associated fecal contamination in addition to three antibiotic resistant genes (ARGs): tetracycline resistance gene (tetQ), sulfonamide resistance gene (sul1), and Klebsiella pneumoniae carbapenemase resistance gene (blaKPC). Subsequently, 16S rRNA gene sequencing was conducted to characterize bacterial community differences between stormwater BRC inflow and outflow. Untreated urban stormwater reflects anthropogenic contamination, suggesting it as a potential source of contamination to waterbodies and urban environments. When comparing inlet and outlet BRC samples, urban stormwater treated via biofiltration did not increase microbial hazards, and changes in bacterial taxa and alpha diversity were negligible. Beta diversity results reveal a significant shift in bacterial community structure, while simultaneously enhancing the water quality (i.e., reduction of metals, total suspended solids, total nitrogen) of urban stormwater. Significant correlations were found between the bacterial community diversity of urban stormwater with fecal contamination (e.g. dog) and ARG (sul1), rainfall intensity, and water quality (hardness, total phosphorous). The study concludes that bioretention technology can sustainably maintain urban microbial water quality without posing additional public health risks, making it a viable green infrastructure solution for heavy rainfall events exacerbated by climate change.

Temporary Urbanism as a Catalyst for Social Resilience: Insights from an Urban Living Lab Practice-Based Research

This research paper investigates the impact of Urban Living Labs (ULLs) on social resilience within urban communities, with a specific focus on the Multicultural City ChatterBox project in Portsmouth, the UK. Drawing on a rich body of literature and empirical data collected through ethnographic research methods, including interviews, focus groups, and participant observations, this study explores how participatory placemaking and co-creation activities foster community resilience. The ChatterBox project, a collaborative effort between the local community and researchers, led to the construction of a temporary timber pavilion in an underutilized urban space, serving as a vibrant hub for social interaction and engagement among diverse community groups. Our findings reveal that ULLs significantly contribute to enhancing social resilience by empowering communities, fostering a sense of belonging, and facilitating the development of social networks. Through the process of co-design and co-creation, participants not only gained a deeper understanding and ownership of their urban environment but also developed valuable skills and knowledge, thus strengthening their capacity to adapt to societal challenges. Furthermore, this study highlights the role of ULLs in bridging gaps between different community groups, thereby promoting inclusivity and social cohesion. The Multicultural City ChatterBox project exemplifies how ULL interventions can serve as catalysts for social innovation, offering flexible and adaptive solutions to urban challenges while simultaneously enriching the social fabric of cities. This paper contributes to the growing discourse on urban resilience, placemaking, and community-led urban development, providing valuable insights for policymakers, urban planners, and community organizers seeking to foster resilient and vibrant urban communities.

Healthy Neighbourhoods Hub (HNH) Framework: A Practical Guide for Fostering Healthy and Inclusive Living in Florence’s Urban Environment

By 2050, an estimated 69% of the global population will reside in urban areas, underscoring the pivotal role of city neighbourhoods in enhancing quality of life by respecting and accommodating diverse identities and needs. The physical environment of neighbourhoods significantly influences community health and well-being, alongside social factors and access to health services. In Italy, prioritising health-promoting and accessible designs in neighbourhoods can form a solid foundation for urban health strategies. This study introduces a theoretical framework developed for the Healthy Neighbourhoods Hub (HNH) project in Florence, Italy, aiming to enhance health and accessibility across different scales. The HNH framework categorises healthy and inclusive neighbourhoods into 7 themes, 25 general characteristics, and 67 specific attributes, supported by verifiable variables derived from comprehensive research and design tools. This innovative framework addresses the need for multilevel, multidisciplinary approaches, and spatialization efforts to ensure equitable benefits for all community members.

Potential drivers of vector-borne pathogens in urban environments: European hedgehogs (Erinaceus europaeus) in the spotlight

Vector-borne diseases (VBDs) are considered as (re-)emerging, but information on the transmission cycles and wildlife reservoirs is often incomplete, particularly with regard to urban areas. The present study investigated blood samples from European hedgehogs (Erinaceus europaeus) presented at wildlife rehabilitation centres in the region of Hanover. Past exposure to B. burgdorferi sensu lato (s.l.) and tick-borne encephalitis virus (TBEV) was assessed by serological detection of antibodies, while current infections with Borrelia spp., Anaplasma phagocytophilum, Rickettsia spp., Neoehrlichia mikurensis, Bartonella spp., Babesia spp. and Spiroplasma ixodetis were investigated by (q)PCR. Of 539 hedgehogs tested for anti-Borrelia antibodies, 84.8% (457/539) were seropositive, with a higher seropositivity rate in adult than subadult animals, while anti-TBEV antibodies were detected in one animal only (0.2%; 1/526). By qPCR, 31.2% (168/539) of hedgehog blood samples were positive for Borrelia spp., 49.7% (261/525) for A. phagocytophilum, 13.0% (68/525) for Bartonella spp., 8.2% for S. ixodetis (43/525), 8.0% (42/525) for Rickettsia spp. and 1.3% (7/525) for Babesia spp., while N. mikurensis was not detected. While further differentiation of Borrelia spp. infections was not successful, 63.2% of the A. phagocytophilum infections were assigned to the zoonotic ecotype I and among Rickettsia spp. infections, 50.0% to R. helvetica by ecotype- or species-specific qPCR, respectively. Sequencing revealed the presence of a Rickettsia sp. closely related to Rickettsia felis in addition to a Bartonella sp. previously described from hedgehogs, as well as Babesia microti and Babesia venatorum. These findings show that hedgehogs from rehabilitation centres are valuable sources to identify One Health pathogens in urban areas. The hedgehogs are not only exposed to pathogens from fleas and ticks in urban areas, but they also act as potent amplifiers for these vectors and their pathogens, relevant for citizens and their pets.

Navigating modernity: young adults’ perspective on urban transformation in three Lima neighbourhoods

ABSTRACT This article delves into young adults’ perceptions in Lima regarding urban modernization and its relationship with architectural styles and facades. Through semi-structured interviews and visual aids, the study examines how young adults perceive modernity in their urban environment and the discrepancies between their interpretations and conventional notions promoted by developers. Findings reveal a divergence between the envisioned improvements by modernists and the scepticism expressed by young adults, raising questions about the essence of modernization and its implications for Lima. The study underscores the importance of reconciling these discrepancies to ensure urban development aligns with the aspirations of Lima’s residents.

Enhancing trash classification in smart cities using federated deep learning

Efficient Waste management plays a crucial role to ensure clean and green environment in the smart cities. This study investigates the critical role of efficient trash classification in achieving sustainable solid waste management within smart city environments. We conduct a comparative analysis of various trash classification methods utilizing deep learning models built on convolutional neural networks (CNNs). Leveraging the PyTorch open-source framework and the TrashBox dataset, we perform experiments involving ten unique deep neural network models. Our approach aims to maximize training accuracy. Through extensive experimentation, we observe the consistent superiority of the ResNext-101 model compared to others, achieving exceptional training, validation, and test accuracies. These findings illuminate the potential of CNN-based techniques in significantly advancing trash classification for optimized solid waste management within smart city initiatives. Lastly, this study presents a distributed framework based on federated learning that can be used to optimize the performance of a combination of CNN models for trash detection.

#2550 Micro(nano)plastics in human urine: a surprising contrast between Chongqing's urban and rural regions

Abstract Background and Aims Microplastics (100 nm-5 mm) and nanoplastics (<100 nm) collectively referred to as micro(nano)plastics (MNPs), which are emerging pollutants all over the world. Environmental differences affect its distribution. The content of MNPs differs between urban and rural environments, according to previous studies. Method To understand the actual situation of human exposure to MNPs in various environments, this study collected 12 urine samples from volunteers in urban and rural regions of Chongqing and used pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and laser direct infrared spectroscopy (LDIR) to detect and analyze MNPs in urine. Results With an average abundance of 1.50 (2.31) mg/kg, MNPs were found in 9 samples by Py-GC/MS. Polyethylene (PE), polyvinyl chloride (PVC) and polyamide 66 (PA66), three different types of MNPs were found, with PE content being the highest among them. By using LDIR, MNPs were found in 7 samples, with an average abundance of 15.17 (23.13) particles/kg. Five different types of MNPs were found, with acrylates (ACR) being the main type, followed by polymethylmethacrylate (PMMA), polyurethane (PU), polypropylene (PP), polyethylene terephthalate (PET). Conclusion The findings demonstrated that urban region had much greater levels and more types of MNPs in human urine than rural. Additionally, regular contact with plastic toys and the use of personal care products are linked to the presence of MNPs. The influence of environmental factors on the actual exposure of the human body to MNPs was preliminary explored in this study, and two different methods were used for the first time to simultaneously detect and analyze MNPs in human urine. This allowed for the feasibility of comprehensively and effectively quantitatively analyzing the actual exposure of the human body to MNPs, and also provided the theoretical foundation for further research on the harm of MNPs to human health in different environments.

Dynamics of Heat Island Intensity in a Rapidly Urbanizing Area and the Cooling Effect of Ecological Land: A Case Study in Suzhou, Yangtze River Delta

Ecological land could play an important function in climate regulation to mitigate urban heat islands (UHIs) and enhance the quality of the living environment. In this work, we chose Suzhou as our case study for urban agglomeration in the Yangtze River Delta (YRD), eastern China. In this city, we analyzed the dynamics of heat island intensity from 2000 to 2021 by retrieving land surface temperature (LST). Subsequently, we examined the relationship between the urban thermal environment pattern and land use change, and finally, we explored the cooling effect provided by ecological land. The results indicated that, in 2000, the city’s UHI effect primarily centered around the central urban region as a singular patch; however, since 2014, the patch UHI effect in the central urban region has been mitigated, and the original small hotspots have converged into a large, contiguous expanse spreading outward. As the shift has occurred from low- to high-temperature zones, the proportion of conversion between ecological land has been decreasing, while the opposite trend has been seen for the proportions of ecological land transferred out and for unchanged artificial surfaces. The normalized difference built-up index was found to be the main contributor to the UHI effect, followed by the normalized difference vegetation index. These findings provide novel insights into the regulation of ecosystem services during urban expansion and offer a reference for improving the function of the cooling effect through urban renewal activities and the optimization of spatial planning.