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The increase in greenhouse gas emissions prompts the transport sector towards new technological perspectives on personal mobility. Addressing sustainable mobility through electric micromobility requires interdisciplinary design research methods and approaches. In the context of the LEONARDO project, funded under the Horizon 2020 framework, this paper addresses a critical literature review on the design thinking, design research models, tools, and mixed methods to be undertaken for driving product mobility innovation in a cross-disciplinary context. Following the “research through design” research strategy, the authors applied the Double-Diamond design thinking model to frame the design research process in four phases, aligning with three overarching objectives, four specific research objectives, and 24 research tasks, supported by a total of 71 mixed methods and tools. As a result, the transdisciplinary process provides a co-designed energy-efficient stand-alone microvehicle and a scalable interdisciplinary design model for urban transport product innovation. In conclusion, this case study suggests the value of the Double-Diamond design thinking model as a design research instrument capable of addressing sustainable mobility and guiding interdisciplinary design research, design practice, and education in the industrial engineering and design disciplinary sectors. Full article

In the context of urban space constraints, subway and underground projects have become crucial strategies to alleviate urban congestion and enhance residents’ quality of life. However, pit engineering, a frequent accident area in geotechnical engineering, urgently requires innovative safety monitoring technologies. Traditional monitoring methods face challenges such as high labor costs, lengthy monitoring cycles, high-risk working environments, and over-reliance on human judgment. To address these issues, this paper introduces an innovative monitoring system integrating Fiber Bragg Grating (FBG) sensing technology based on a subway pit project in Guangzhou. This system not only achieves fully automated data acquisition but also includes an intelligent monitoring cloud platform, providing unprecedented automated and intelligent monitoring solutions for support structures and the surrounding environment during mechanical shaft construction. The key findings of this paper include the following: (1) The breakthrough application of distributed optical fiber monitoring technology, including successfully deploying this advanced technology in complex pit engineering environments, enabling the precise and continuous monitoring of support structures and surrounding changes, and demonstrating its high effectiveness and intelligence in practical engineering. (2) The innovative design of an intelligent safety monitoring system. By integrating sensors and wireless communication technology, an efficient data networking architecture is constructed, supporting remote configuration and flexible adjustment of monitoring equipment, significantly enhancing data collection‘s real-time performance and continuity while greatly reducing safety risks for field staff, achieving an intelligent upgrade of monitoring work. (3) Comprehensive and accurate empirical analysis. During shaft excavation, the monitoring data collected by the system were stable and reliable, with all indicators maintained within reasonable ranges and closely matching expected changes caused by construction activities, validating the system’s practical application effectiveness in complex construction environments and providing a scientific basis for pit engineering safety management. Full article

Rectangular culverts are extensively employed in various municipal projects. Due to their frequent placement in weak strata within urban areas, these structures are susceptible to defects like cracks, which can significantly reduce their bearing capacity and even result in collapse or other failures. This study investigates the mechanical behavior of cracked rectangular culverts through laboratory tests, analyzing both the failure mechanisms and the impact of crack depth on the ultimate bearing capacity (UBC) of the culverts. Focusing solely on the effect of crack depth on the UBC of rectangular culverts with defects, this paper establishes fundamental assumptions and proposes a calculation method for the residual bearing capacity (RBC) of rectangular culverts under crack-induced conditions. The theoretical calculations closely align with the experimental results. The findings indicate that (1) the failure process of a rectangular culvert under trilateral normal external load can be categorized into the initial stage with no visible cracks, the crack progression stage, and the final failure stage; (2) the increase in crack depth leads to a decrease in the UBC of the rectangular culvert, indicating that cracks have a negative impact on its bearing capacity; and (3) when the crack depth reaches the protective layer’s thickness, the UBC of the rectangular culvert reduces by over 30%, providing further evidence that an increase in crack depth significantly diminishes its bearing capacity. Full article

Resource-depleted cities face challenges of land structure imbalance and ecological environmental degradation, necessitating relevant research. Clarifying the land use evolution path and exploring the rationality of urban expansion are of significant importance for the sustainable development of resource-depleted cities. This study employs a comprehensive approach utilizing the land use transfer matrix, expansion intensity, expansion speed, and the equal fan analysis method to investigate the evolution characteristics of construction land in Puyang, a typical resource-exhausted city in China, from 1990 to 2020. Additionally, it identifies the driving factors based on a comprehensive approach combining the variance inflation factor (VIF), grey relational analysis, and Pearson correlation analysis. The main findings include the following: (1) From 1990 to 2020, the cultivated land area in Puyang decreased by 181,296 hectares, while the newly added construction land amounted to 24,846.30 hectares, primarily converted from cultivated land. (2) Puyang comprises five counties and one district. Among them, Hualong District exhibited the highest expansion intensity, speed, and area, whereas Taiqian County showed the lowest. This disparity is attributed to resource-centered land development and utilization. (3) From 1990 to 2020, urban expansion in Puyang primarily concentrated in the northeast direction, exhibiting a concentric outward expansion pattern. (4) Socioeconomic factors positively influenced the expansion of construction land, with the “year-end total population” having the most significant impact. Conversely, land use and natural resource factors negatively impacted construction land expansion, with “cultivated land area” being the most prominent. Additionally, policy and institutional frameworks played a regulatory and restrictive role in the evolution of construction land, while topography and location served as fundamental conditions for urban expansion. This study provides methodologies for sustainable development research in resource-exhausted cities and offers a foundation for land use planning research in resource-based regions of China. Full article

The family Chironomidae is speciose and is present in almost all freshwater habitats. Adult non-biting midges emerge from waterbodies and swarm in high numbers, occasionally disrupting people’s outdoor activities. In order to understand the seasonal dynamics of species composition, a continuous observation of non-biting midge diversity was performed. Adult non-biting midges were collected using light traps from the autumn of 2022 to the summer of 2023 in an urban wetland park. Species were identified based on morphological characteristics and DNA barcodes. Alpha diversity was evaluated using Margalef, Pielou, and Shannon–Wiener indexes. Beta diversity was evaluated using unconstrained NMDS analysis and constrained CCA. The impacts of environmental factors, including barometric pressure, temperature, relative humidity, and wind speed, on the variation in species composition were estimated in the constrained analyses. A total of 42 species were identified, with 29 species belonging to Chironominae, 9 species belonging to Orthocladiinae, and 4 species belonging to Tanypodinae. The species composition varied across different seasons. Summer sites and autumn sites shared the highest similarity in diversity, and spring sites presented the lowest diversity. The variation was significantly correlated with environmental conditions. The results showed that seasonality is a factor influencing the diversity of adult non-biting midges. Full article

Background: Influenza poses a substantial health burden, especially among older adults in China. While vaccination is one of the most effective preventions, influenza vaccine uptake rates among Chinese older adults remain low. This study examines the individual and combined effects of behavioral interventions based on the Information–Motivation–Behavioral Skills (IMB) model and economic incentives in promoting influenza vaccine uptake among older adults living in China. Methods: The study will recruit 640 older adults living in eight communities that have not been covered by the free influenza vaccination policy. These eight communities (as clusters), stratified by urban and rural, will be randomized to four parallel arms, including a usual care arm, an IMB-based behavioral intervention arm, a conditional economic incentive arm, and a combined behavioral-economic arm. The interventions will start from the beginning of the flu season and last for about one month. Specifically, the IMB-based behavioral intervention encompasses health education brochures, healthcare provider-led lectures, interactive quizzes, and personalized consultations. The exact number of economic incentives is conditional on the timing of vaccination (a higher amount for early immunization) and the number of people within a household to be vaccinated at the same appointment (a higher amount for more people). The primary outcome is the influenza vaccination rate. Data will be gathered through vaccination records and questionnaires covering IMB-based vaccination cognitions. Mixed-effects models will be used to analyze the outcome of vaccination rate, reporting difference-in-differences estimates with 95% confidence intervals. Conclusions: The results of this study have the potential to inform influenza vaccination program scaleup among older adults who are not yet covered by the free influenza vaccination policy. Ethics and dissemination: Ethics approval has been granted by the ethics commission of Peking University Health Science Centre (IRB00001052-24090). Participants will be required to sign a written consent form. Findings will be reported in conferences and peer-reviewed publications in accordance with the recommendations of the Consolidated Standards of Reporting Trials. Registration number: This study was registered at the Chinese Clinical Trial Registry (ChiCTR2400090229). Full article

Cities concentrate many people, and studies have shown that resultant urban heat islands can be intense. Urban parks can function as “cool islands” that mitigate heat island effects. This study used the microclimate model ENVI-met 5.1 to assess the cooling effect of Panyu Park in the center of Shanghai, China. The primary objectives were to increase the diversity of data sources and to conduct a microclimate analysis. Two scenarios were examined: the actual park and no park. The results indicated that (1) the integration of satellite technology enhanced the data sources for ENVI-met and thereby increased the efficiency of urban modeling and (2) the simulated results for the park correlated well with the actual data observed at weather stations. The presence of the park resulted in a decrease in the maximum air temperature by 0.1 °C at 1.4 m above ground, a decrease in the wind speed by 1.67 m/s, a maximum increase of 0.2% in relative humidity, and a reduction of 1.94 in the Predicted Mean Vote. The results demonstrated the applicability of multi-source satellite data in microclimate research, saved time on data collection, and provided valuable information for studies undertaken in areas where the collection of field data is challenging and/or historical data are unavailable. Full article

Toxicity identification evaluation (TIE) is used to support sustainable soil management. However, TIE studies for sediment contamination have been limited and no previous study has validated its applicability to a species native to South Korea, to the best of our knowledge. Therefore, this study aims to validate the applicability of domestic species inhabiting East Asia to a TIE framework. We selected Glyptotendipes tokunagai, a common benthic invertebrate in urban areas. Contaminated sediment samples were generated using cadmium, copper, and ammonia, which are the major pollutants in sediment. Three different adsorbents were chosen as pollutant removal agents to validate the applicability of TIE using G. tokunagai. In the results, G. tokunagai exhibited a mortality rate that was dependent on the concentration of each pollutant. The mortality rate dramatically decreased after adding the chosen adsorbents to the contaminated sediments. Additionally, the observed reduction in toxicant concentrations suggests that these additives are efficient for toxicant removal. In contrast, WCA10L showed a mortality higher than 20% and seems not to be a proper additive for a toxicity assay. Through this study, G. tokunagai was demonstrated to be sufficiently sensitive to sediment contaminated with different pollutants and showed reproducible measurements, making it a suitable test organism for the TIE framework. Moreover, suitable adsorbents were suggested by measuring efficiency and toxicity after the toxicant removal procedure. Full article

The acceleration of urbanization with the increased proportion of impermeable surfaces has posed significant challenges for old urban drainage systems, particularly during periods of heavy rainfall. Urban initial rainwater runoff pollution, containing a considerable quantity of pollutants, has severely contaminated the urban water environment. The present study presented an A/O–magnetic flocculation (A/O-MF) process for the rapid treatment of urban initial rainwater runoff pollution to realize the simultaneous removal of NH₄⁺-N, TN, COD, TP, and SSs. The optimal operation parameters were obtained by the single-factor and orthogonal methods. The results showed that the optimal operation duration of the A/O process was 10 min for the anoxic process and 60 min for the aerobic process. The optimal dosages of the flocculants were 105 mg/L for PAC, 3 mg/L for PAM, and 30 mg/L for Fe₃O₄ with a sedimentation time of 2 min. To treat the actual runoff rainwater, the A/O-MF process improved the removal efficiencies of TP, SSs, NH₄⁺-N, and COD compared with the single A/O process, with efficiencies of 99.5%, 93.3%, 99.7%, and 91.3%, respectively. The total operation duration was only 74 min, which could enable the rapid and efficient treatment of urban runoff rainwater. Full article

As unconventional building structures, container houses are now widely used in urban tourism to create characteristic buildings. Nowadays, natural gas accidents occur frequently in cities and towns; however, the development of laws and influencing factors of natural gas accidents in container buildings have rarely been studied. In this paper, a natural gas explosion test was carried out in an ordinary container house, and a numerical simulation was carried out according to the test results. The influence of methane proportion, ignition position, pressure-relief area, and pressure-relief intensity on the explosion load was analyzed. Research shows that natural gas will gather from top to bottom during the process of leakage and diffusion, and vertical stratification will occur. The most unfavorable working condition is 9.5% methane. Using the roof of the container house as a pressure-relief panel can effectively control the influence range of natural gas explosion accidents and help reduce accident losses. It is suggested that the stacking of container buildings should be reduced as much as possible, and the roof strength should be weakened to ensure structural safety. The research results have certain reference values for the disaster prevention and reduction design of urban characteristic buildings. Full article

This paper presents a comparative study that examines the effects of the Dubai Creek extension on its hydrodynamics and water flushing dynamics. Dubai Creek (Khor Dubai) is a 24 km long artificial seawater stream located in the emirate of Dubai. The creek has experienced the impact of the rapid urbanization of Dubai and a major 13 km extension project, which connected the creek to the Arabian Gulf from the other side. In this paper, two-dimensional hydrodynamic and flushing models were created using Delft3D Flexible Mesh (2021.03) to investigate the water circulation and water quality of the creek before and after the extension. The hydrodynamic models were calibrated and validated to accurately simulate water levels and currents with correlation values close to 1 and very small RMSE and bias. Flushing models were created to simulate water renewal along the creek. The results of the flushing models showed a significant improvement in the flushing characteristics of pollutants in terms of the residence times of the extended creek (Existing Creek) model compared to the old one (Old Creek). This improvement emphasized the positive impact of the creek extension project on the local aquatic ecosystem and its overall water quality. Full article

Flooding hazards due to climate change are increasingly becoming a frequent global occurrence. The aim of this study is to provide a comprehensive review of the various structural mitigation and adaptation strategies available to engineers and designers at various stages of road construction and rehabilitation to increase the resilience of roads to flooding damage. The criteria for categorising the various strategies available were the time of intervention with respect to the occurrence of the hazard. Thus, all studied strategies were separated into pre-construction design changes, post-construction mitigation and adaptation options like Sustainable Urban Drainage Systems (SuDS). The main findings were that changing the specifications of commonly used materials can provide increased flood resilience, and a preliminary design for flooding can reduce post-flooding rehabilitation. The study can be used as a guide for the different options available to deliver a design that takes flooding into consideration. Full article

Carex is a type of herbaceous plant with high application value, playing an important role in the urban periphery. Due to its unique morphology and ecological characteristics, Carex is widely used in various fields, such as landscaping, ecological restoration and soil and water conservation, which help to maintain the balance of the ecosystem. In order to explore the potential molecular mechanisms of shade tolerance in Carex, transcriptome and metabolome sequencing were performed on the leaves of the shade = tolerant species Carex adrienii E. G. Camus. under 80% shade and no shade conditions. Compared to control group (CK), the total chlorophyll, chlorophyll a, chlorophyll b and total carotenoid content in the C. adrienii leaves of the shading treatment were significantly upregulated. The antioxidant enzyme activity of the leaves, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), were also remarkably upregulated in the shading treatment groups. In addition, the net photosynthesis rate (Pn), stomatal conductance (Gs) and transpiration rate (Tr) of the leaves were reduced, and the intercellular CO₂ concentration (Ci) of the leaves was increased under shade. The transcriptome identified 5056 differentially expressed genes (DEGs) and the metabolome identified 889 differential accumulated metabolites (DAMs) in three treated samples. The integrated transcriptomic and metabolomic analyses results showed that the DEGs and DAMs were enriched in photosynthesis, plant hormone signal transduction and flavonoid biosynthesis synthesis pathways. The ABA content of the C. adrienii leaves was significantly increased under shade. Therefore, the shading conditions led to changes in chlorophyll and abscisic acid (ABA), as well as the accumulation of flavonoids in C. adrienii, both of which were achieved by regulating genes involved in photosynthesis, plant hormone signal transduction and flavonoid biosynthesis molecular networks. Our results provide new knowledge for the molecular response and metabolic regulatory mechanisms of C. adrienii to shade stress, and valuable genetic resources for C. adrienii shade tolerance molecular breeding. Full article

This study investigates the impact of comprehensive reforms on the economic development and environmental protection of resource-based cities in China within the context of the `National Sustainable Development Plan for Resource-based Cities (2013–2020)’. Employing a difference-in-differences methodology, we find that these reforms not only bolster economic stability but also significantly enhance urban ecological environment, resulting in a win–win outcome for economic prosperity and environmental preservation. Our analysis reveals that the reforms drive sustained economic growth and ecological enhancement by downsizing industries, adopting green technologies, and optimizing industrial composition. Moreover, we identify that these impacts are more pronounced in mature and declining cities and in regions with robust official promotion strategies and stringent environmental regulations. These findings provide valuable insights for addressing the “resource curse” within social systems and for formulating policies that balance stable economic growth and environmental protection in resource-based cities. Full article

Chinese cities are increasingly developing exclusive bicycle paths to improve the safety and efficiency of bicycle transit. The width of bikeways is a critical factor influencing cyclists’ safety and comfort, with insufficient width identified as a major contributor to bicycle accidents. Therefore, determining the minimum operational width for human-powered bicycles is essential for bikeway design. While some countries’ design manuals consider speed as a factor in determining width, there is a lack of field experiments to validate these specifications from the perspective of cyclists’ safety and comfort. This study addresses this gap by conducting a field experiment to measure cycling workload, which reflects safety and comfort under different widths and cycling speeds. The experiment involved 12 cyclists on a test road, where cycling workload was measured at various preset widths and cycling speeds for a single human-powered cyclist. The results were further validated using conventional lateral distance measurement techniques, which are used in the existing literature to determine the cycling width. The results show that wider bikeway widths lead to a lower cycling workload, enhancing comfort and safety. However, both very high (over 20 km/h) and very low (under 5 km/h) speeds significantly increase cyclists’ workload, which in turn requires a wider path to maintain a safe and comfortable cycling experience. The study found that a minimum width of 0.90 m may be adequate for cyclists traveling at speeds between 10 and 15 km/h, while a width of 1.0 m is sufficient for speeds ranging from 5 km/h to 25 km/h, provided the bicycle width does not exceed 0.62 m. Given that cyclists typically progress from slower to faster speeds, a minimum operational width of 1.0 m is recommended for most cases. This study highlights the importance of considering cyclists’ workload in determining appropriate bikeway widths. It provides valuable insights for designing safer, more comfortable bike paths and reducing bicycle accidents, contributing to the sustainable development of urban cycling infrastructure. Full article