Search Results (682)

Whereas environmental effects on driver cognition have been extensively studied in ground transportation, research linking low-altitude visual environment characteristics to pilot cognitive load (CL) in urban air mobility (UAM) remains scarce. This study combines multimodal physiological data with explainable machine learning to elucidate how low-altitude visual environments influence pilots’ CL. First, a CL quantification framework integrating electroencephalography (EEG) and eye-tracking data is developed to capture real-time cognitive dynamics during flight. Second, multidimensional visual environment indicators are extracted from low-altitude urban landscape images captured during simulated flights using computer vision techniques. These indicators, combined with flight dynamics features, serve as input variables for constructing pilot CL prediction models via machine learning approaches. The results demonstrate that a Bayesian-optimized XGBoost model achieves superior predictive performance. Further interpretability analysis based on SHAP reveals that environmental contrast and the visibility of buildings and water bodies are key factors influencing pilot CL. Additionally, significant interaction effects are also identified among spatial morphology, color characteristics, and landscape typology, with certain landscape elements exhibiting marked variations in both importance and directional influence across different low-altitude flight scenarios. These findings inform low-altitude route optimization, urban morphological regulation, and blue-green infrastructure configuration, advancing an air-ground synergistic planning paradigm. Full article

While silver halides (AgX) are promising visible-light photocatalysts for water remediation, their practical deployment is severely hindered by intrinsic photocorrosion, rapid charge recombination, and macroscopic recovery challenges. Here, we demonstrate a monolithic AgX/biomass carbon aerogel composite platform, constructed by anchoring AgX nanocrystals in situ onto a 3D hierarchical carbon skeleton. The carbon network not only suppresses nanoparticle aggregation but also plays contrasting optical roles: amplifying the intrinsic visible-light absorption of AgBr while endowing the otherwise UV-confined AgCl with substantial visible-light response. Consequently, the optimal 30 wt% AgBr/CA composite achieves a 95.68% methylene blue degradation efficiency within 60 min—outperforming pristine AgBr by 2.6-fold—while establishing robust activity against two additional, structurally distinct pollutants: rhodamine B and the colorless antibiotic ciprofloxacin. Notably, the free-standing monolith retains exceptional activity over six consecutive cycles. Mechanistic investigations reveal that the carbon aerogel functions as an electron-accepting reservoir, which accelerates interfacial charge separation and steers electron flow toward superoxide radical generation. Notably, XRD and XPS analyses confirm that no detectable metallic Ag⁰ is present in the as-prepared composites. This work establishes a sustainable and scalable architectural paradigm for designing highly efficient, stable, and easily recyclable photocatalytic systems. Full article

The lack of freshwater in the world requires a paradigm shift from linear water consumption to resilient and low-energy desalination technologies. Although reverse osmosis (RO) is the standard in the industry, its usefulness is essentially constrained by concentration polarization (CP) and non-useful hydraulic pressure losses. This paper applies a high-fidelity computational model in ANSYS Fluent 2022 R1 to conduct a comparative parametric evaluation of hexagonal and sinusoidal feed-spacer geometries relative to a baseline grid configuration. The solute concentration gradients at the fluid–membrane interface were solved using a 3D species transport model, which was optimized using one-micron near-wall inflation layers. The hexagonal configuration produced the lowest maximum membrane-surface salt mass fraction, decreasing it from 0.1127 kg/kg for the baseline grid to 0.0429 kg/kg, corresponding to a 61.9% reduction. Although the hexagonal design required an inlet pressure of 205.7 Pa, it produced a more favorable normalized mass-transfer–friction trade-off than the sinusoidal configuration (447.8 Pa), with a System Performance Index (η) of 2.53. These results demonstrate comparative micro-scale improvements in concentration polarization control and hydraulic performance under the simulated conditions. Experimental testing and system-level modeling are required before conclusions can be drawn regarding full-module energy consumption, photovoltaic integration, long-term fouling behavior, or economic feasibility. This study is consistent with the emerging Concepts and design for sustainability, whereby a circular and energy-efficient water economy is facilitated through an innovative mechanical design. Full article

Western Kazakhstan is one of the most climate-vulnerable macro-regions in Central Asia. Intensifying aridification, acute water scarcity, and active land degradation are already undermining its ecosystems and an economy built heavily on oil and gas. Yet investment in the region is still driven by short-term priorities rather than a systematic assessment of actual need. A previous study by the authors identified a significant investment gap for sustainable development in the Aktobe region, and showed that this problem calls for comprehensive, comparative analyses rather than a localized one. This study aims to assess and compare investment needs for sustainable development across the four regions of Western Kazakhstan (Aktobe Atyrau, West Kazakhstan, and Mangystau) for 2021–2024, accounting for sustainability thresholds derived from optimal population density. An improved eco-economic methodology was applied, combining per capita investment need calculations with thresholds indicators of regional vulnerability and adaptive capacity, based on official statistical and sectoral data. The results revealed substantial inter-regional differences in investment needs, driven by differing economic specializations, and pointed to an urgent need for targeted investment in water infrastructure modernization, land degradation prevention, and renewable energy development. A new development paradigm is proposed that integrates sustainability thresholds into investment planning, with region-specific recommendations, offering a reproducible framework for arid regions worldwide. The study’s limitations include its short data coverage period (2021–2024), its reliance on official statistics, and the indirect nature of the population-density threshold. The proposed framework was tested for the hydrocarbon-dependent arid regions of Western Kazakhstan. Full article

Bacterial disease is a major constraint on Magallana gigas larval production, yet hatchery microbiology has been characterised almost exclusively through the lens of Vibrio, and rarely across the whole production chain. We tracked bacterial communities throughout an entire larval rearing cycle at a commercial hatchery in northern China. A total of 78 samples were collected from the full production chain, from water intake to larvae. Bacterial communities were characterised using 16S rRNA (V4–V5) amplicon sequencing and culture-based isolation, with larvae sampled from three replicate tanks at six developmental stages. A protracted mortality event began at the D-veliger stage, with cumulative losses of roughly 40% before sinking ceased; ostreid herpesvirus 1 was not detected. The only taxon that rose above its healthy baseline during larval mortality was a single undescribed a single undescribed amplicon sequence variant (ASV) of the family Cryomorphaceae. Its relative abundance increased to a mean of 41% (with a tank-to-tank range of 33.7–51.6%) before disappearing once the mortality event concluded. No described species exceeds 92.2% 16S rRNA gene sequence identity to it, whereas its closest environmental relatives (97–98%) are, without exception, uncultured bacteria associated with marine invertebrates. It was an order of magnitude more abundant in larvae than in the surrounding water. Vibrio rose transiently at the onset of mortality but fell below its healthy-stage abundance while larvae were still dying. Tenacibaculum, by contrast, was the dominant genus of the rearing water yet was never recovered on Vibrio-selective medium and showed no association with mortality. Chlorination of the feed-room supply removed Tenacibaculum while leaving Vibrio uncontrolled. These findings reveal the limitations of the Vibrio-targeted, culture-based paradigm that has long dominated hatchery microbiology, as it overlooks both prevailing water-column organisms and mortality-linked taxa. Our results highlight the need for whole-community, culture-independent surveillance to better understand larval disease. Full article

The aim of this study is to explore the fire resilience of traditional ancient villages in Huizhou, China, and to reveal “traditional environmental planning knowledge” as a spatial survival strategy for high-density settlements. This study adopts a qualitative interpretive paradigm, combining historical geography with a literature review, field surveys, and overlay analysis. The study found that these villages, during site selection, utilized basin topography to construct a multi-level disaster mitigation system encompassing “macro-level water systems, meso-level alleyways, micro-level firewalls, and sandwich fire-extinguishing floors.” This endogenous physical technology, based on defensive awareness and community agreements, achieves a dynamic balance of resilience between humans and the environment. The cultural interpretation based on the indicators in this study primarily reflects the disaster resilience potential of traditional planning. The conclusions should be carefully interpreted within the framework of traditional environmental design. Furthermore, commercial intervention, infrastructure renovation, and population loss are leading to the neglect of this defensive space. This lack of a holistic perspective will trigger the “resilience degradation” of ancient villages. Future research urgently needs to establish a “resilience decay model” to quantitatively assess the disaster resistance capabilities remaining after damage to the surrounding buffer space, based on traditional environmental planning knowledge. Full article

Digital Twin (DT) technology has emerged as a transformative approach in pipeline engineering, enabling real-time monitoring, predictive analytics, and enhanced decision-making across the asset lifecycle. This review critically examines recent advancements in the application of digital twins for pipeline systems, with a particular focus on condition monitoring, leak detection, corrosion assessment, and predictive maintenance. The study synthesizes findings from a wide range of literature to identify key enabling technologies, including Internet of Things (IoT) sensors, data-driven modeling, computational fluid dynamics (CFD), and machine learning algorithms. Special attention is given to the integration of physics-based and data-driven models for improving the accuracy and reliability of digital twin frameworks. In addition, this paper proposes a unified reference architecture for pipeline digital twins, supported by a mathematical formulation of synchronization and a comparative synthesis of existing approaches. The review highlights how digital twins facilitate early fault detection and operational optimization by continuously synchronizing physical assets with their virtual counterparts. The review also emphasizes the importance of uncertainty-aware and reliability-informed digital twin frameworks for robust decision-making in safety-critical pipeline applications. Applications in subsea, oil and gas, and water distribution pipelines are explored, demonstrating the versatility of DT systems under different environmental and operational conditions. Despite significant progress, challenges remain in data integration, model validation, scalability, and cybersecurity. Furthermore, the lack of standardized architectures and interoperability frameworks limits widespread adoption. This paper concludes by outlining future research directions, including the development of hybrid modeling techniques, edge computing integration, and AI-driven autonomous decision systems. Overall, digital twin technology represents a paradigm shift in pipeline engineering, offering substantial potential to enhance safety, efficiency, and sustainability in complex infrastructure systems. Full article

The global wine industry generates substantial volumes of by-products, leading to significant environmental and economic challenges. This study explores the sustainable valorization of two key by-products from Moldovan red wine production—yeast lees and grape skin powder derived from autochthonous grape varieties Rară Neagră (RN) and Fetească Neagră (FN)—within the circular economy paradigm. Comprehensive physicochemical analyses demonstrated that yeast lees are a rich source of bioactive β-glucans (20.17–21.91%, w/w wet lees), proteins, and triglycerides; β-glucans of this type are reported in the literature to confer immunomodulatory and antioxidant properties, although these bioactivities were not directly evaluated in the present study. Grape skin powders exhibited high dietary fibre content and polyphenolic compounds, with FN showing superior total polyphenol content and antioxidant activity compared to RN. Advanced extraction techniques using green solvents such as glycerol, propylene glycol, and ethanol, including ultrasound-assisted methods, optimized polyphenol recovery while maintaining extract stability. Incorporation of these extracts into innovative oil-in-water cosmetic emulsions revealed notable physicochemical characteristics, with the RN extracts enhancing emulsion firmness via polyphenol–xanthan gum interactions, and the FN extracts providing high antioxidant potential without compromising texture. A preliminary single-subject biophysical assessment suggested good short-term skin compatibility, with hydration improvement and reduced transepidermal water loss in several formulations and no visible pigmentation; these observations require confirmation in a larger volunteer panel with dedicated safety testing. This work provides laboratory-scale evidence of the dual environmental and functional potential of recovering and applying Moldovan winery by-products, supporting their further development—pending pilot-scale and economic validation—as bio-ingredients for the food, cosmetic, and pharmaceutical sectors within a circular bioeconomy framework. Full article

Understanding how the spatiotemporal variability of precipitation affects ecosystem respiration (RE) is central to carbon–climate feedback in climate-smart agriculture, yet remains unresolved for the alpine agricultural region of the southern Qinghai–Tibet Plateau, where flux observations are sparse. Using 25 years (2000–2024) of monthly gridded climate and remote sensing data for the Yarlung Zangbo River Basin and Its Two Tributaries Basin, we developed a flux tower-constrained reference–respiration (R_ref) environment-matching model in which R_ref varies with the enhanced vegetation index (EVI) and land surface temperature (LST) to correct the Lloyd–Taylor parameterization. The correction reduced the RE root mean square error by 54.8% (1.04 → 0.47 gC·m⁻²·month⁻¹) and eliminated systematic bias (+0.80 → −0.001) relative to an independent gridded RECO product. We then constructed a multidimensional index of precipitation variability (intra-annual concentration, interannual variability, long-term trend, spatial clustering) and combined random forest, spatial regression, lag analysis, and structural equation modeling (SEM) to disentangle direct and indirect pathways from precipitation variability to RE. The central finding is an indirect-conduction mechanism: precipitation concentration (PCI) affects RE almost entirely through vegetation productivity (PCI → GPP → RE, indirect effect −0.676) rather than directly (direct effect +0.076, opposite in sign), because low temperature and high soil water holding capacity buffer the immediate soil moisture response. The basin functions as a net carbon source (mean NEP = −0.550 gC·m⁻²·month⁻¹) with a significant warming-driven interannual RE increase (Sen’s slope = 0.0025 yr⁻¹, p = 0.022) that is independent of the stable precipitation total. The framework offers a transferable paradigm for carbon flux attribution in alpine regions under sparse observation. Full article

The escalating global contradiction between water supply and demand has imposed novel imperatives on regional water security within the paradigm of resilient city development. To elucidate the supply–demand dynamics of water provisioning services under heterogeneous institutional contexts, this study selected the Guangdong–Hong Kong–Macao (GHKM) region as the empirical study area. Employing the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model, we coupled meteorological, land-use/land-cover (LULC), and pedological data to quantify the provisioning of water yield services in 2024. Concurrently, sector-specific water demands—encompassing agricultural, industrial, domestic, and ecological categories—were accounted for using statistical yearbooks. Subsequently, a Supply–Demand Index (SDI) was formulated to delineate the spatial matching patterns. The findings reveal pronounced spatial heterogeneity in water service provisioning; high-value zones are predominantly aggregated along the western and southern coastal belts, whereas low-value zones are dispersed across the northern mountainous terrains. Based on the SDI classification, the study area comprises 12 supply-surplus, 6 supply–demand-equilibrium, and 5 supply-deficit administrative units. Notably, the northern Guangdong mountainous region assumes a critical ecological role in water conservation, whereas the core megalopolises of the Pearl River Delta exhibit an acute dependency on extrinsic water subsidies, with Macao demonstrating a distinct ecological deficit in water provisioning. Furthermore, this study uncovers the overestimation artifact of water yield estimations over urban impervious surfaces, thereby providing a robust empirical foundation for the cross-regional synergistic governance and adaptive management of water resources. Full article

The concurrent disposal of industrial lithium slag (LS) and the remediation of heavy-metal-contaminated water remain critical environmental imperatives. Herein, industrial lithium slag was successfully upcycled into a high-capacity geopolymer via alkali activation to systematically evaluate its Pb(II) removal mechanisms. Synthesized under optimal conditions (11 mol/L alkali concentration, 0.616 solid-to-liquid ratio), the geopolymer showed exceptional Pb(II) capture, achieving ~99% removal efficiency within 120 min for a 100 mg/L Pb(II) solution at pH 6.0. The adsorption kinetics obeyed the pseudo-first-order model, yielding a remarkable theoretical equilibrium capacity of 284 mg/g. Thermodynamic results reveal a spontaneous (ΔG < 0), endothermic (ΔH = 17.66 kJ/mol) process with increased interfacial randomness (ΔS > 0). Integrating macroscopic performance with characterizations and density functional theory (DFT) computations elucidated a site-specific chemisorption mechanism and the precipitation of PbSO₄ caused by Pb(II) and SO₄²⁻ in LS. Ultimately, this work provides a sustainable paradigm for the value-added upcycling of industrial solid waste. Full article

The paradigm of sustainable development, coupled with contemporary inclinations towards green construction, exerts a considerable effect on the evolution of environmentally benign building composites. The main aim of this study is to create geopolymer composites with improved physical and mechanical properties. An examination of the properties of a geopolymer composite (GS), using ground granulated blast furnace slag (GGBFS) and plant fibers, is presented in this paper. Sisal (SF) and flax (FF) fibers, along with their combination (SF + FF), were integrated into the slag at concentrations of 0%, 0.5%, 1.0%, 1.5%, and 2% by weight. Before use, plant fibers were treated with a 5% NaOH solution. The geopolymer composites (GC) underwent evaluation for their density, compressive and flexural strengths, and water absorption characteristics. Scanning electron microscopy was employed to examine the fracture characteristics of the GC. The compressive and flexural strengths of GC were improved by including 1% SF, FF, and their combination, 0.5% SF + 0.5% FF. Compressive strength increases were 11.5%, 8.6%, and 14.5%, while flexural strength increases were 17.4%, 13%, and 19.6%, respectively. Water absorption of GC with 1% SF, FF, and SF + FF decreased by 14.6%, 10.8%, and 20.4%, respectively. The apparent synergistic performance of hybrid sisal-flax reinforcement at a total fiber content of 1% was revealed. GCs at the fracture have a homogeneous rough structure with microcracks and accumulations of geopolymer reaction products. The matrix-plant fiber interface in GC is identified by a rounded region with elongated fibers, indicating the fiber’s performance under mechanical stress. The findings of this investigation suggest the feasibility of utilizing plant fibers in environmentally sound geopolymer construction composites. Full article

Increasing planting density is an effective strategy for improving maize (Zea mays L.) productivity, but it can also intensify interplant competition and canopy shading. Enhanced nitrogen application may help offset these negative effects. A two-year field experiment was conducted in the Hexi Corridor, an arid region of northwestern China, using a full factorial design with three planting density levels D1 (75,000 plants ha⁻¹), D2 (90,000 plants ha⁻¹), and D3 (105,000 plants ha⁻¹), and three nitrogen application levels N1 (198 kg ha⁻¹), N2 (264 kg ha⁻¹), and N3 (330 kg ha⁻¹). The aim was to clarify how the interaction between planting density and nitrogen application regulates maize canopy structure and affects resource use efficiency in arid areas. The results showed that planting density, nitrogen rate, and their interaction significantly affected canopy structure, photosynthetic traits, grain yield, and water and nitrogen use efficiency. From the perspective of each growth stage, combinations of medium and high planting density and nitrogen application levels facilitated the optimization of maize canopy structure, promoted plant growth and dry matter accumulation, and elevated leaf SPAD values. Meanwhile, treatment D2N2 exhibited the most prominent improvement in maize yield components, with grain yield increased by 1.44–35.58% on average across experimental years. This treatment also sustained superior water and nitrogen use efficiency, achieving an average water use efficiency of 3.53 kg·m⁻³ and an average partial factor productivity of nitrogen of 53.41 kg·kg⁻¹. Comprehensive multi-index evaluation verified that D2N2 represented the optimal cultivation regime. This regime could reduce nitrogen fertilizer input by 20% while fully exploiting light and heat resources inherent to arid regions. Collectively, this study establishes a viable green and high-efficiency cultivation paradigm for maize production with high yield, reduced fertilizer input and water conservation, and delivers critical theoretical and technical references for the sustainable intensification of maize cultivation in arid regions of northwest China. Full article

With the rapid advancement of Maritime Autonomous Surface Ships (MASSs), developing intelligent decision-making systems that ensure navigation safety in complex waters has become a core priority for the maritime industry. To address the limitations of oversimplified ship dynamics, the instability in game-based strategies, and the presence of non-compliant ships in multi-ship encounters, a novel decision-making framework is developed based on Multi-Agent Deep Reinforcement Learning (MADRL). A three-degree-of-freedom (3-DOF) manoeuvring modelling group (MMG) model is incorporated to replace conventional constant-speed assumptions. By explicitly modelling the hydrodynamic forces acting on the hull, propeller, and rudder, the proposed framework captures the intrinsic coupling between the speed and heading, thereby ensuring that the generated manoeuvres conform to the physical and operational constraints. To achieve stable decision-making in multi-ship encounters, an MATD3-based decision-making module is integrated within a Centralised Training and Distributed Execution (CTDE) paradigm. This architecture enables ships to derive robust and decentralised policies, while benefiting from global information during training. In addition, the proposed method demonstrates a promising adaptability in the investigated multi-ship encounter scenarios. Simulations are conducted across a set of encounter scenarios restricted to open waters. The results demonstrate that the proposed framework achieves safe collision avoidance performance while generating COLREGs-consistent behaviours in basic encounters involving standard power-driven vessels under open-water conditions. Full article

Suspended sediment concentration (SSC) is a critical proxy for coastal water quality, geomorphological evolution, and biogeochemical cycles. In shallow macro-tidal embayments like Sanmen Bay (SMB), China, surface SSC exhibits highly dynamic spatiotemporal variations driven by intense, multi-scale tidal forcing. Using Sentinel-2 MSI imagery processed with the ACOLITE Dark Spectrum Fitting (DSF) algorithm, this study reconstructs the spatial distribution of surface SSC across the embayment. We then introduce the normalized Suspended Sediment Concentration Asymmetry Index ($A_{ssc}$) to quantitatively diagnose asymmetrical sediment responses across spring–neap and flood–ebb cycles. The results reveal a spatially divergent, dual-control mechanism governing sediment transport across the embayment’s hydro-geomorphic gradients. Quantitative trend-surface fittings and stratified regressions demonstrate that net sediment transport in deep bedrock channels is primarily governed by tidal pumping. Conversely, sediment dynamics on intertidal mudflats and shallow subtidal shoals are modulated by geomorphic resistance, exhibiting high morphodynamic sensitivity to minute water depth variations. By bridging process-based estuarine tidal theory with discrete satellite observations, this reproducible framework transforms multi-temporal remote sensing snapshots into spatially continuous diagnostics, providing a practical decision-support paradigm for coastal engineering and ecosystem management in dynamically analogous macro-tidal environments. Full article