Search Results (935)

Despite the plethora of literature on urban agriculture (UA), an analysis of the reasons why many urban residents in Africa rarely engage in the practice remains incipient. This review examines the irony between large arable land and persistent hunger in African cities. It was inspired by the rising food insecurity driven by the heavy reliance on market-based food, high poverty, and rapid urbanization. The study conducts a systematic review to clarify the debate on why, in the midst of these setbacks, a disproportionate percentage of urban residents do not produce their own food. Through the PRISMA method and five inclusion benchmarks, the paper identified 38 peer-reviewed book chapters and journal articles that provide the underlying rationale for why UA is not prevalent in African cities. The paper found economic, environmental, governance, and prevailing sociocultural conditions as primary barriers. To that end, it suggests avenues for empowering urban residents to transition from simply being consumers to producers. It concludes by identifying the limitations of the paper and new lines of study that ought to be conducted to fully realize the potential of UA across the continent. Full article

New towns often experience a structural transit gap in early stages, where transport supply lags behind population growth. Demand-responsive transit (DRT) has emerged as a promising complementary solution; however, most studies rely on MNL-based ICLV models that do not account for error covariance across alternatives. This study applies an ICLV model, integrating an Error Component Mixed Logit kernel with latent variables, to analyze mode choice behavior in transit-poor new towns. Based on an SP-off-RP survey of 644 residents in new towns, 2576 observations were analyzed. The model incorporates five latent variables, including Transit Dissatisfaction, Convenience, Safety, Travel Time, and Travel Companion Sensitivity, and captures unobserved correlations through a two-level nesting structure. Results show that DRT has a significantly positive alternative-specific constant, indicating latent acceptance beyond observable attributes. DRT adoption is more common among transit-poor new town residents and highly educated individuals, but less common among car owners. Users are more sensitive to access and waiting time than to in-vehicle time. Convenience, Safety, and Travel Time significantly influence DRT utility, while Travel Companion Sensitivity reveals heterogeneous effects across modes. These findings provide behavioral insights for designing effective DRT strategies in transit-poor new towns. Full article

Air quality management in Santiago (Chile) primarily relies on measuring atmospheric particulate matter and other criteria pollutants. This data is generated mostly by fixed-site outdoor monitoring stations, and the results are used to estimate population exposure. However, this approach may not be able to capture individual variability arising from differences in personal behaviors and microenvironmental transitions. Here we conducted an exploratory case study using residential outdoor polyurethane foam passive samplers and personal silicone wristbands to evaluate the potential polycyclic aromatic hydrocarbon exposure patterns among a limited number of residents of Santiago (Chile). Our results suggested that outdoor passive samplers and personal silicone wristbands revealed different but complementary PAH concentration patterns. Outdoor passive samplers captured regional spatial variability, whereas personal samplers revealed greater heterogeneity among individuals even when sharing the same residential environment. These findings support the value of integrating personal passive sampling into future assessment studies in urban environments of Chile. Full article

Smart city mobility is increasingly governed by a techno-solutionist logic that prizes data, automation, and efficiency, often at the expense of public trust, social legitimacy, and lived experience. This article argues that the fate of a mobility transition appears to depend less on the sophistication of the technology than on the pace and posture of change. Building on the CalmMobility framework and on Weiser and Brown’s concept of calm technology, it develops the idea of calm smart mobility—a human-paced, options-first approach in which innovation enters everyday life gradually and with credible alternatives already in place, so that residents are not asked to continuously adapt. The framework’s three pillars (Comprehensiveness; Pacing–Sequencing–Inclusion; Future-Readiness) are mapped onto four recurring challenges of smart mobility (Policy Layering, Affective Mismatch, Governance Silos, and the Future-Readiness Gap) and then used as a descriptive analytical lens to characterize seven documented implementations across economic, spatial, mass-transit, service, and platform interventions and four world regions: the Stockholm congestion charge, the London ULEZ expansion, the Barcelona superblocks, Bogotá’s TransMilenio bus rapid transit and Ciclovía, Seoul’s Cheonggyecheon restoration and bus reform, Helsinki’s Whim Mobility-as-a-Service, and Sidewalk Toronto. Presented through a comparison table, a positioning map, and adoption trajectories rather than rankings, the characterization suggests that the provision of alternatives, the sequencing and pace of change, and the genuineness of co-creation are more closely associated with smooth adoption than the type of instrument deployed. The article is conceptual and framework-building. The cases illustrate and probe the framework instead of validating it, and a testable central hypothesis is specified for future empirical work. Calm smart mobility is offered as a transferable, citizen-centred logic for guiding smart city mobility transitions at a human pace. Full article

The rapid transformation of urban centers into smart environments introduces complex challenges at the intersection of technological advancement, environmental stewardship, and social justice. This study evaluates Lisbon’s smart city transition by establishing an integrated framework that links digital equity with Environmental, Social, and Governance principles. Employing a convergent qualitative research design, this paper triangulates a comprehensive regulatory policy analysis with primary empirical data gathered from twenty-five semi-structured interviews with municipal officials, academic experts, and residents of marginalized communities. The findings expose critical systemic disparities in digital infrastructure deployment, device affordability, and platform literacy across socio-economic strata, demonstrating how localized digital divides directly impede the execution of urban ESG objectives. While green financing mechanisms offer robust pathways for sustainable energy and transit infrastructure, their equity outcomes remain constrained without mandatory, transparent information disclosure systems that mitigate agency costs. Cultivating urban resilience requires shifting from tokenistic e-governance to genuine citizen empowerment. This study offers a novel theoretical contribution by operationalizing corporate ESG metrics within public urban governance frameworks, providing an empirical roadmap for municipal policymakers globally to balance digital innovation with structural inclusion and environmental accountability in smart city agendas. Full article

The increasing generation of organic waste and the growing demand for sustainable solid fuels have intensified interest in hydrothermal carbonisation (HTC) as a pathway for biomass valorization within circular bioeconomy systems. HTC uses subcritical water to upgrade moist biomass into hydrochar with improved fuel properties and combustion behavior. This review correlates key HTC parameters, including temperature, residence time, pH, and the nature of feedstock, with the chemical evolution and thermal reactivity of different hydrochars. Data synthesis identifies a typical ‘kinetic optimization’ range between 180 and 220 °C for conventional lignocellulosic feedstocks. Within this thermal interval, activation energy (E_a) decreases from 180–260 kJ/mol for raw biomass to 70–180 kJ/mol for hydrochars, while the high heating value (HHV) reaches up to ~28 MJ/kg. The results further demonstrate that feedstock composition strongly influences combustion reactivity and kinetic behavior under similar HTC conditions. The integration of isoconversional methods with thermodynamic parameters (ΔH, ΔG, ΔS) confirms a transition toward more ordered and thermally stable carbon structures. Additionally, Criado’s master plots indicate a shift from diffusion-controlled to reaction-controlled combustion mechanisms with increasing HTC severity. These findings provide valuable insights into the optimizing of HTC conditions for balance energy densification and combustion reactivity, offering a comprehensive understanding to guide future hydrochar-based energy applications and scale-up studies. Full article

Advancing urban sustainability transitions through effective environmental policies requires understanding how residents perceive and respond to policies. While perceived policy effectiveness (PPE) has been studied in waste management and recycling programs, its role in shaping demand for bio-based materials remains underexplored. This study investigates whether and how PPE is associated with bamboo product consumption among 1121 urban residents in Zhejiang Province, China. Drawing on an extended Theory of Planned Behavior (TPB) framework, we use ordinary least squares estimators to examine the direct and interactive associations between PPE and actual bamboo consumption behavior. Results show that PPE is significantly and positively associated with bamboo product consumption. Interaction analysis reveals heterogeneous effects: PPE shows a weak positive interaction with environmental knowledge, but a negative interaction with environmental values. This suggests that policy signals may complement cognitive preparedness while partly compensating for low value-based motivation. A supplementary analysis indicates that this conditioning extends to economic resources, with the association concentrated among lower-income, more price-sensitive consumers. This study extends PPE research from post-consumption management to the purchasing stage of sustainable products. It highlights the role of policy perceptions in shaping demand-side adoption of lower-impact materials, with implications for urban sustainability transitions and city-level policies promoting bio-based alternatives. Full article

This study, through a hybrid approach to post-occupancy evaluation (POE) of four types of high-energy-efficiency housing in rural Scotland, explores the manifestation, formation mechanism, and mitigation pathways of energy risks in high-energy-efficiency housing from environmental and socioeconomic dimensions. The findings reveal a “high-efficiency paradox”: better fabric performance and lower heating demand do not guarantee reduced carbon emissions, fuel poverty alleviation, or energy resilience. Actual energy risks are formed by the combined effects of multiple factors, including building size, energy infrastructure, resident characteristics, energy prices, and policy, exhibiting a clear systemic coupling characteristic. The study further verifies that, in the context of rural Scotland, relying solely on indicators such as EPC may lead to misjudgements of housing sustainability. Heating demand, total energy consumption, carbon emissions, and energy expenditure exhibit a partially decoupled relationship. Thus, rural housing sustainability should shift from a technically efficient approach to a comprehensive strategy integrating design, infrastructure, affordability, and social equity. The study proposes context-specific mitigation pathways including multi-source energy systems, place-sensitive policies, socio-economic support, and a multi-criteria assessment framework, providing empirical references for rural housing energy transition and energy risk governance. Full article

(1) Introduction: Transit-oriented development is often framed as a strategy to expand opportunity and advance equitable transportation. However, evidence suggests it can also contribute to rising housing costs and displacement in historically marginalized communities. This study examines how a light rail expansion reshaped displacement risk in a Latina/o community in the U.S. Southwest, identifying early mechanisms through residents’ interpretations of the expansion during construction. (2) Materials and Methods: Using a qualitative, community-engaged design, the study draws on ten in-depth pláticas with Latina/o residents conducted during construction of a major rail expansion. Data were analyzed abductively and guided by Critical Race Ecological Systems Theory (CrEST) to identify multilevel mechanisms linking infrastructure policy to lived social conditions. (3) Results: Findings identify three mechanisms through which transit investment generated displacement risk prior to relocation. First, historical and intergenerational memory shaping anticipatory displacement. Second, place-based belonging intensifying psychosocial stress and loss. Third, policy-mediated mobility constraining residents’ ability to remain or benefit from reinvestment. (4) Discussion: Transit infrastructure operates as a structural policy intervention that reorganizes risk, belonging, and stability when histories of racialized disinvestment are not incorporated into policy design. These findings position infrastructure planning as a critical site for social work policy analysis and prevention-oriented intervention. Full article

The blast furnace–basic oxygen furnace long process is the dominant steel production route in China. Increasing the scrap ratio is an effective way to reduce cost and carbon emissions, and scrap preheating is a key technology to achieve a high scrap ratio. To improve the low thermal efficiency and poor deep-bed melting performance of converter gas-based scrap preheating, an innovative process using oxygen-enriched combustion in a hot metal ladle is proposed. Numerical simulation is essential for capturing the complex multiphysics phenomena, as real-time monitoring of melting inside the packed scrap bed is extremely difficult. In this study, a novel multiphysics approach based on a User-Defined Function (UDF) is developed to dynamically track the progressive melting of the scrap skeleton, overcoming the key limitation of conventional enthalpy–porosity models that cannot capture the feedback between phase change and porous medium property evolution. A three-dimensional transient model was established, integrating turbulent combustion, gas–solid convective heat transfer in porous media, and solid–liquid phase change. The effects of impact pit depth, scrap porosity, and converter gas flow rate on temperature distribution, melting behavior, and thermal efficiency were systematically investigated. Results showed that porosity had the strongest influence; thermal efficiency increased from 33.92% to 65.59% as porosity rose from 0.6 to 0.8, due to a transition from conduction-dominated to coupled convection–conduction heat transfer. Converter gas flow rate exhibited a non-monotonic effect, peaking at 3688.14 m³·h⁻¹, highlighting a trade-off between energy input and gas residence time, while impact pit depth showed a limited effect with diminishing returns. A 600 s full-process simulation revealed stage-dependent melting, and the initial phase was crucial for process optimization. The optimal condition, with a pit depth of 64 cm, porosity of 0.8, and converter gas flow rate of 3688.14 m³·h⁻¹, achieved a 1.23% melting fraction and 65.59% thermal efficiency within 120 s. These findings clarify the combined roles of geometric confinement, permeability, and energy-residence time interactions, providing guidance for industrial scrap preheating design. Full article

Autoimmune myocarditis frequently progresses to inflammatory cardiomyopathy through dysregulated immune–stromal interactions. This study employs single-nuclei RNA-sequencing (snRNA-seq) to profile 46,233 cardiac nuclei from the experimental autoimmune myocarditis (EAM) mouse model at four timepoints: day 0 (healthy), day 14 (inflammation), day 21 (acute inflammation), and day 40 (late cardiac remodelling). Single-nuclei RNA profiling identified 18 transcriptionally distinct cell populations. Global cell–cell communication analysis revealed a dramatic peak of intercellular signalling at day 14 (5907 interactions), with fibroblast subpopulations and macrophages as dominant hubs, followed by partial resolution at day 21 (2264 interactions) and renewed remodelling at day 40 (4862 interactions). Subclustering of the macrophage compartment identified five subpopulations: Mac-TLF, Mac-MHCII, Mac-rMHCII, Mac-ResL, and Classical Monocytes. Tissue-resident macrophages (Mac-TLF, CCR2-) dominated at healthy state (~55%) but were rapidly depleted at day 14, coinciding with a dramatic influx of recruited CCR2⁺ macrophages (Mac-rMHCII), which expanded to over 70% of the compartment and maintained dominance through day 40. At inflammation (day 14), the expanded Mac-rMHCII subpopulation displayed a strongly pro-inflammatory signature (Il1b, Stat2, Parp14, Apoe), and the overall macrophage compartment was enriched for cytokine response, Fc-gamma receptor, and Notch signalling pathways, while downregulating homeostatic and mitochondrial metabolic programmes, potentially contributing to impaired efferocytosis and cardiomyocyte dysfunction. Macrophage-centred communication networks expanded markedly at day 14 (1047 interactions), with resting fibroblasts (FB-R) as the primary signalling partner, driving pro-inflammatory stromal activation marked by upregulation of Ccl2, Ccl7, and Csf2. Intra-macrophage subcluster communication also intensified at this timepoint (447 interactions). These findings delineate the temporal and functional heterogeneity of cardiac macrophages during EAM progression and identify key immune–stromal interactions driving pathological cardiac remodelling. The coexistence of pro-inflammatory and transitional reparative macrophage subsets highlights the limitations of broad immunosuppression and supports precision strategies targeting CCR2-mediated recruitment, the SPP1 signalling axis, and macrophage–fibroblast crosstalk as therapeutic avenues in myocarditis and its progression. Full article

Introduction: Long-term ecological monitoring is essential to understand the responses of fish communities to global change in transitional ecosystems. Coastal lagoons are particularly vulnerable to eutrophication, which can trigger abrupt regime shifts, mass mortality events, and loss of ecological functions. The Mar Menor coastal lagoon (SE Spain) represents one of the most impacted Mediterranean systems, providing a unique opportunity to assess long-term ecological responses of fish assemblages to sustained anthropogenic pressure. Objetives: This study aims to synthesize long-term monitoring data to evaluate structural, functional, and population-level responses of fish assemblages to eutrophication processes, and to identify critical habitats and mechanisms supporting resilience. Methodology: We integrated multiple datasets derived from long-term monitoring programs (2002–2004 as and 2018–2025), including community structure, functional diversity, population dynamics of resident species, and habitat-based indicators. Analyses encompassed pre-impact, eutrophication, and post-disturbance phases, allowing for a multi-scale assessment of ecological responses. Results: Eutrophication-driven disturbances caused major shifts in fish assemblages, including declines in biomass and abundance, species-specific responses, and increased dominance of opportunistic trophic groups. Functional diversity analyses revealed strong homogenization processes and loss of specialist traits, indicating reduced ecosystem functionality. Population dynamics of resident species reflected habitat degradation, highlighting their value as ecological indicators. Despite these impacts, shallow coastal habitats acted as critical refuges, buffering hypoxic conditions and enabling partial persistence and recovery of fish communities. Conclusions: Our results demonstrate that long-term monitoring provides essential insights into the mechanisms driving fish community responses to eutrophication. The identification of functional changes and refuge habitats is key for adaptive management. Protecting and restoring critical habitats, particularly shallow areas, is crucial to enhance resilience and guide conservation strategies in Mediterranean coastal lagoons under global change. Full article

Renal-resident macrophages (RMs) are essential regulators of kidney homeostasis and repair, yet the mechanisms governing RM niche regeneration after acute depletion remain poorly defined. To overcome these limitations, we have developed an inducible human CD59- intermedilysin (hCD59-ILY) ablation system, enabling rapid, specific, and reversible depletion of targeted macrophage populations, and subsequent replenishment of RMs, followed by longitudinal scRNA-seq analysis of kidneys at baseline and days 1, 3, and 7 post-ablation. RM ablation triggered a rapid and sustained upregulation of Cx3cl1, predominantly in proximal tubular epithelial cells (PTC1/PTC2), establishing a persistent chemotactic niche signal that coincided with macrophage repopulation. Regenerating RMs transitioned from inflammatory/stress-associated states toward metabolically active and proliferative phenotypes enriched in glycolysis, oxidative phosphorylation, MYC, and cell-cycle programs, with attenuation of canonical inflammatory pathways. Cell–cell communication analysis revealed an early burst of intercellular signaling at day 1, followed by progressive normalization, with fibronectin (Fn1), osteopontin (Spp1), chemokine (Ccl), and amyloid precursor protein (App) axes emerging as key mediators of niche restoration. Transcriptional network analysis identified a conserved regulatory module (Tfe3, Mitf, Hif1a, Myc, Gabpa, Rcor1) coordinating macrophage differentiation and regenerative programming, linking metabolic adaptation to lineage reconstitution. Sub-clustering revealed five dynamically shifting RM subsets with distinct inflammatory, remodeling, proliferative, and surveillance states, reflecting a hierarchical regeneration process. Functional validation using clodronate-mediated depletion in Secreted Phosphoprotein 1 (Spp1) (Opn)-deficient mice demonstrated impaired macrophage repopulation, establishing osteopontin as a critical regulator of RM regeneration. Together, these data define a coordinated epithelial–immune circuit in which Cx3cl1-driven chemotaxis, Spp1-dependent signaling, and a core transcriptional network orchestrate macrophage niche reconstitution and kidney repair following acute immune cell ablation. Full article

Current evaluation of bypass graft performance relies predominantly on wall shear stress metrics, even though thrombosis and atherogenesis are fundamentally governed by particle transport and residence within disturbed flow regions. This disconnect limits the ability of conventional hemodynamic indicators to capture mechanisms directly linked to graft failure. In this study, we investigate how helical bypass geometry reorganises the flow and, consequently, modifies transport behaviour within the distal anastomosis by combining experimentally validated flow visualisation with computational fluid dynamics under pulsatile conditions. Particle transport was quantified using a controlled injection of 151 tracers, enabling direct assessment of retention and washout across the graft–anastomosis system. The straight configuration exhibited persistent recirculation structures that promoted localised particle retention and delayed clearance. In contrast, the helical geometry disrupted these structures, enhancing flow mixing and accelerating downstream transport. At late stages of the cardiac cycle, the helical configuration reduced residual particle retention by approximately 43% compared to the straight bypass. These findings demonstrate a transition from recirculation-driven retention to washout-dominated transport, providing a mechanistic basis for interpreting bypass performance beyond shear-based metrics. This transport-centred perspective provides a mechanistic link between flow organisation and particle residence, supporting the functional relevance of helical graft design while remaining distinct from direct modelling of biological thrombosis or atherogenesis. Full article

Weekday commuting and weekend recreation are two mobility domains through which urban spatial structure shapes residents’ well-being and urban functioning, yet direct empirical evidence on how they are related remains limited. This study investigates how weekday commuting costs and weekend recreational mobility conditions are related within a jobs–housing–recreation spatial framework, using individual-level location-based services (LBS) data from the central urban area of Chongqing, China. Generalized additive models reveal a nonlinear and range-dependent commuting–recreation relationship. Distance-based and driving-time specifications provide the main evidence for a U-shaped relationship, whereas transit-time specifications do not clearly reproduce this pattern, reflecting short-distance cost overestimation and spatially shared public-transport constraints rather than realised mobility conditions. From a spatial-configuration perspective, this pattern suggests that work-related and recreational mobility conditions are unevenly combined across residential locations, rather than simply aligned or opposed. It also suggests that relatively favourable commuting and recreational mobility conditions can coexist within some residential contexts. Rather than establishing a universal rule, the Chongqing case provides a testable hypothesis that may be relevant to large cities with uneven and partially aligned employment, housing, transport, and recreational opportunities. The study provides an empirical entry point for integrated spatial-performance diagnosis and future evaluation of alternative jobs–housing–recreation configurations. Full article