Search Results (4,671)

The development of urban green infrastructures (UGI) is considered among the main nature-based solutions for climate mitigation in cities; however, the role of soils in the carbon (C) balance of UGI ecosystems remains largely overlooked. Urban green spaces are typically dominated by constructed Technosols, created by adding organic materials on top of former natural or agricultural subsoils. The combined effects of land-use history and current UGI management result in a high spatial variation of soil organic carbon (SOC) stocks and soil CO₂ emissions. Our study aimed to explore this variation for the case of Wageningen University campus. Developed on a former agricultural land, the campus area includes green spaces dominated by trees, shrubs, lawns, and herbs, with well-documented management practices for each vegetation type. Across the campus area (~32 ha), a random stratified topsoil sampling (n = 90) was conducted to map the spatial variation of topsoil (0–10 cm) SOC stocks. At the key sites (n = 8), representing different vegetation types and time of development (old, intermediate, and recent), SOC profile distribution was analyzed including SOC fractionation in surface and subsequent horizons, as well as the dynamics in soil CO₂ emissions, temperature, and moisture. Topsoil SOC contents on campus ranged from 1.1 to 5.5% (95% confidence interval). On average, SOC stocks under trees and shrubs were 10–15% higher than those under lawns and herbs. The highest CO₂ emissions were observed from soil under lawns and coincided with a high proportion of labile SOC fraction. Temporal dynamics in soil CO₂ emissions were mainly driven by soil temperature, with the strongest relation (R² = 0.71–0.88) observed for lawns. Extrapolating this relationship to the calendar year and across the campus area using high-resolution remote sensing data on surface temperatures resulted in a map of the CO₂ emissions/SOC stocks ratio, used as a spatial proxy for C turnover. Areas dominated by recent and intermediate lawns emerged as hotspots of rapid C turnover, highlighting important differences in the role of various UGI types in the C balance of urban green spaces. Full article

To investigate drug delivery in cancer therapy, we integrate fluorescence lifetime measurements, microspectrometry, and confocal laser scanning microscopy to track the uptake of inorganic–organic hybrid nanoparticles (IOH-NPs) by breast cancer cells over incubation periods ranging from 2 to 24 h. Non-radiative energy transfer (FRET) from the LysoTracker Green to the IOH-NPs confirms their lysosomal localization and possibly improves their optical excitation. Beyond the resolution limits of light and electron microscopy, fluorescence lifetime kinetics—including FRET—can thus reveal the nanoscale cellular localization of IOH-NPs and guide the optimization of fluorescence excitation. Here, we extend optical microscopy into a fifth dimension—picosecond fluorescence decay times—complementing 3D spatial and spectral information, establishing lifetime measurements as a versatile tool to study nanoparticle uptake in cancer therapy. Full article

Climate change affects surface water quality parameters, including river quality. This study analyses changes in climate parameters, specifically air temperature and solar radiation, and their impact on river water temperature. It also examines how changes in river water temperature and organic matter load affect oxygen saturation levels, a key indicator of river water quality. Using water quality data, the status as well as temporal and spatial trends of the analysed parameters were assessed for the period between 2007 and 2024 on the three largest Slovenian rivers: the Drava, Mura, and Sava. Relative importance analysis of temperature and biochemical oxygen demand (BOD) using the Random Forest machine learning method showed that water temperature in the analysed rivers has an impact ranging from 51% to 66% on predicting oxygen saturation. The selected approach to analysing watercourse quality parameters enables the assessment of the impact of these parameters on river water quality. Based on these results, it will be possible to implement appropriate measures promptly to achieve sustainable river management by establishing a strategy that, under climate change conditions, safeguards water quality and maintains ecosystem protection, ensuring long-term ecological and socio-economic benefits. Full article

Understanding how different pools of sediment organic carbon (OC) are associated with trace metals is essential for interpreting biogeochemical processes in small freshwater ecosystems. This study examines spatial and interannual patterns of total organic carbon (TOC), water-extractable organic carbon (WEOC), and cadmium (Cd) in sediments collected from streams, natural ponds, and drying ditches across three contrasting regions of Lithuania during 2022–2024. TOC and WEOC exhibited pronounced spatial gradients and a marked increase in 2023, while Cd showed a similar but more moderate temporal response. Correlation analysis, principal component analysis, regression modelling, and structural equation modelling consistently indicated that WEOC is more strongly associated with sediment Cd concentrations than bulk TOC. The results suggest that TOC influences Cd distribution primarily indirectly, through its control on the water-extractable OC pool. Multivariate analyses revealed a dominant organic–metal association gradient shared by TOC, WEOC, and Cd, as well as a secondary axis reflecting partial geochemical independence of Cd. These findings highlight the functional relevance of WEOC as an interface between sediment organic matter and Cd accumulation in small freshwater systems. Incorporating WEOC into sediment monitoring may improve interpretation of trace-metal patterns under conditions of hydrological variability. Full article

Iron (Fe) is an essential micronutrient for plant development and productivity. Nevertheless, the role of gibberellins (GAs) in the control of iron homeostasis is less studied compared to other growth regulators. We found that GAs modulate iron homeostasis in maize by inducing deficiency-like responses independent of rhizosphere iron availability. Plant phenotyping demonstrated that exogenous GA₃ application under iron-sufficient conditions phenocopied iron deprivation, while inhibiting GA biosynthesis with mepiquat chloride prevented the development of typical symptoms of Fe deficiency (–Fe). Gibberellins positively control strategy II Fe uptake genes, albeit indirectly, as opposed to the direct negative transcriptional regulation of phytosiderophore biosynthesis. Additionally, gibberellins disrupt iron partitioning by suppressing root-to-shoot Fe translocation, causing iron overaccumulation in roots of GA₃ treated plants. A functional ferrous iron uptake pathway was identified and was found to operate in conjunction with the strategy II uptake pathway via the differentially regulated Zea mays Iron-Regulated Transporter (IRT) paralogs ZmIRT1 and ZmIRT2. Root responses are spatially organized: gene expression in the lateral root sector reflects the shoot iron status, while transcriptional responses in the root apex correlate with local Fe demands. This study demonstrates that maize leverages a hybrid ferric/ferrous iron uptake strategy and establishes novel roles of GAs as pivotal regulators of iron homeostasis. Full article

Investigating how climatic and hydrological conditions in ecological resource-enriched zones of marginal seas respond to external forcing, particularly during past greenhouse climates, holds considerable significance for understanding current environmental and resource challenges driven by global warming. In marginal seas, climatic hydrological states, including salinity, redox conditions, and productivity, are key environmental parameters controlling organic matter production, preservation, and ultimately the formation of high-quality shale. Herein, high-resolution cyclostratigraphic and multi-proxy geochemical analyses were conducted on a continuous core from the upper part of Member 4 of the Eocene Shahejie Formation (Es4cu) in Well NY1, Dongying Sag, Bohai Bay Basin. Based on these data, a refined astronomical timescale was accordingly established for the studied interval. By integrating sedimentological observations with multiple proxy indicators, including elemental geochemistry (e.g., Sr/Ba and Ca/Al ratios), organic geochemistry, and mineralogical data, the evolution of climate and paleo-water mass conditions during the study period was reconstructed. Spectral analyses revealed prominent astronomical periodicities in paleosalinity, productivity, and redox proxies, indicating that sedimentation was modulated by cyclic changes in eccentricity, obliquity, and precession. It was hereby proposed that orbital forcing governed periodic shifts in basin hydrology by regulating the intensity and seasonality of the East Asian monsoon. Intervals of enhanced summer monsoon associated with high eccentricity and obliquity were typically accompanied by increased sediment supply and intensified chemical weathering. Increased precipitation and runoff raised the lake level while promoting stronger connectivity with the ocean. In contrast, during weak seasonal monsoon intervals linked to eccentricity minima, basin conditions shifted from humid to arid, characterized by reduced precipitation, lower lake level, decreased sediment supply, and a concomitant decline in proxies for water salinity. The present results demonstrated orbital forcing as a primary external driver of cyclical changes in conditions favorable for resource formation in the Eocene lacustrine strata of the Bohai Bay Basin. Overall, this study yields critical paleoclimate evidence and a mechanistic framework for predicting the spatial-temporal distribution of high-quality shale under comparable astronomical-climate boundary conditions. Full article

Background: Hypoxic–ischemic (HI) brain injury triggers a dynamic, multi-phase response involving early microglial efferocytosis followed by extracellular matrix (ECM) deposition and scar formation. Arginase-1 (ARG1), a key enzyme in tissue repair, is implicated in both processes, yet its role in neonatal microglia remains poorly defined. We characterize ARG1-linked pathways in neonatal microglia, identifying distinct efferocytic and fibrotic phases post-HI. Methods: HI was induced in P9 mice using the Vannucci model, and brains were collected at 24 h (D1) and 5 days (D5). Spatially resolved single-cell transcriptomics (seqFISH) was performed using a targeted panel enriched for microglial, ARG1-pathway, efferocytosis, and profibrotic genes. Cell segmentation, clustering, and spatial mapping were conducted using Navigator and Seurat. Differential expression, GSEA, and enrichment analyses were used to identify time- and injury-dependent pathways. Results: Spatial transcriptomics identified 12 transcriptionally distinct cell populations with preserved neuroanatomical organization. HI caused the expansion of microglia and astrocytes and the loss of glutamatergic neurons by D5. Microglia rapidly activated regenerative and profibrotic programs—including TGF-β, PI3K–Akt, cytoskeletal remodeling, and migration—driven by early DEGs such as Cd44, Reln, TGF-β1, and Col1a2. By D5, microglia adopted a collagen-rich fibrotic state with an upregulation of Bgn, Col11a1, Anxa5, and Npy. Conclusion: Neonatal microglia transition from early efferocytic responses to later fibrotic remodeling after HI, driven by the persistent activation of PI3K–Akt, TGF-β, and Wnt/FZD4 pathways. These findings identify microglia as central regulators of neonatal scar formation and highlight therapeutic targets within ARG1-linked signaling. Full article

This review describes the immunosuppressive effect of secreted phosphoprotein 1 (SPP1)+ tumor-associated macrophages (TAMs) in coordinating the tumor microenvironment (TME) as a functionally unique myeloid cell subgroup. SPP1+ TAMs transcend the traditional M1/M2 paradigm and represent a group of cells that are widely found in various cancer types. SPP1+ TAMs have the characteristics of high expression of SPP1 and promoting immune escape, matrix remodeling and metastasis. We clarify the dual developmental source of SPP1+ TAMs, and introduce the activation process of SPP1+ TAMs through recruitment, polarization and epigenetic locking. After SPP1+ TAMs are activated, they are strategically enriched in the tumor core and tumor marginal area to play their functions. Functionally, SPP1+ TAMs mainly promote the progression of tumors through three mechanisms: (1) Interacting with cancer-associated fibroblasts (CAFs): constructing an immunoexcluded fibrotic niche; (2) Multiple regulation of immune cells; (3) Promoting tumor metastasis and the construction of pre-metastatic niche (PMN). Overall, this review aims to provide a comprehensive overview of the mechanisms mediated by SPP1+ TAMs in the TME, and emphasize their unique role in cancer progression. At the same time, the treatment strategies targeting them are further explored, highlighting their potential as precise therapeutic targets for tumor treatment. Full article

The spatial localization of plant secondary cell wall polymers is a controversial issue. A relief of parallel-organized cellulose microfibrils was discovered, on the surface of which spherical nanoparticles were visualized. Spherical nanoparticles with a diameter of 20–50 nm were isolated using size exclusion chromatography from an aqueous extract of differentiating xylem of Norway spruce and visualized by SEM and AFM. The composition of isolated nanoparticles was determined by pyrolytic GC-MS, ¹H NMR spectroscopy, and nitrobenzene oxidation, followed by separation of the products by liquid chromatography. Lignin was detected in the isolated nanoparticles already at the stage of cell wall formation. The hypothesis about the intracellular synthesis of lignin was proposed based on the results obtained. Lignin in the form of a lignocarbohydrate complex is formed not in the cell wall, but inside the cell. The formation of lignin–carbohydrate complexes occurs in Golgi apparatus and vesicles, which discharged into the inner surface of the cell wall simultaneously with the deposition of cellulose microfibrils. A new model of the structure of secondary cell wall postulates the formation of cellulose microfibrils surrounded by lignin–carbohydrate spherical complexes having a carbohydrate shell and an aromatic core. Full article

Driven by factors such as meteorology, topography, and industrial structure, the concentrations of volatile organic compounds (VOCs) exhibit significant spatial heterogeneity. Investigating the characteristics and sources of VOCs in different regions is therefore crucial for formulating targeted strategies to mitigate their contributions to fine particulate matter (PM_2.5) and ozone (O₃) pollution. This study comprehensively investigated—for the first time—the concentration characteristics, sources, and contributions to secondary organic aerosol (SOA) and O₃ formation of VOCs at an urban background site in Ganzhou, a southern Chinese city, based on hourly observations of VOCs during 2023. Analyses included ozone formation potential (OFP), secondary organic aerosol formation potential (SOAFP), and positive matrix factorization (PMF) source apportionment. The influence of photochemical loss was assessed using a photochemical age parameterization method. The results showed an annual average total VOC concentration of 22.6 ± 13.17 ppbv, with higher levels in winter and lower in summer. Alkanes were the dominant species (45.76%). After correcting for photochemical loss, the initial concentration of VOCs (IC-VOCs) was approximately 60% higher than the observed concentration of VOCs (OC-VOCs), with alkenes becoming the dominant group in IC-VOCs (≈72%). OFP analysis indicated that the OFP calculated using initial VOC concentrations (IC-OFP) was substantially higher (by 320 μg/m³) than the values calculated using observed VOC concentrations (OC-OFP), primarily due to the increased contribution of alkenes. SOAFP was higher in spring and winter, and lower in summer and autumn, with aromatic hydrocarbons being the dominant contributors (>85%). PMF results based on month-case studies identified combustion and industrial process sources as the major contributors (>20%) in August, while combustion and vehicle exhaust dominated in January. Photochemical loss significantly influenced source apportionment, particularly leading to an underestimation of biogenic emissions during a warm month (August). These findings underscore the necessity of accounting for photochemical aging and offer a scientific basis for refining targeted VOC control measures in Ganzhou and similar regions. Full article

Rapid urbanization and persistent air pollution threaten the functional resilience of megacities in Southeast Asia, particularly Bangkok, where PM_2.5 concentrations consistently exceed World Health Organization (WHO) guidelines. To strengthen urban adaptive capacity, this study investigates the role of Nature-based Solutions (NbS), particularly urban green spaces, as resilience-oriented infrastructure for air quality management. Using data from 32 monitoring stations across the Bangkok Metropolitan Administration (BMA) and surrounding areas from 2021 to 2023, spatial and temporal trends in PM_2.5 concentrations were analyzed through geostatistical modeling and inferential statistics. Although all sites exceeded the WHO PM_2.5 guideline of 5 µg/m³, larger and more connected green spaces consistently exhibited better air-quality than the surrounding non-green urban mosaic. Areas with extensive vegetation, greater canopy cover, and more compact park geometries (lower perimeter-to-area ratios) demonstrated improved pollution attenuation capacity, while fragmented parks are more exposed to surrounding emissions. Integration of Local Climate Zone (LCZ) classification further indicated that compact high-rise zones and high-traffic corridors exhibited higher PM_2.5 levels due to reduced airflow and structural confinement. The study underscores the need to embed NbS within resilience-based urban planning to promote long-term environmental stability and public health recovery in rapidly urbanizing megacities like Bangkok. Full article

Polar sea ice is undergoing rapid change, with recent record-low extents in both hemispheres, raising the demand for skillful predictions from days to seasons for navigation, ecosystem management, and climate risk assessment. Accurate sea ice prediction is essential for understanding coupled climate processes, supporting safe polar operations, and informing adaptation strategies. Physics-based numerical models remain the backbone of operational forecasting, but their skill is limited by uncertainties in coupled ocean–ice–atmosphere processes, parameterizations, and sparse observations, especially in the marginal ice zone and during melt seasons. Statistical and empirical models can provide useful baselines for low-dimensional indices or short lead times, yet they often struggle to represent high-dimensional, nonlinear interactions and regime shifts. This review synthesizes recent progress of DL for key sea ice prediction targets, including sea ice concentration/extent, thickness, and motion, and organizes methods into (i) sequential architectures (e.g., LSTM/GRU and temporal Transformers) for temporal dependencies, (ii) image-to-image and vision models (e.g., CNN/U-Net, vision Transformers, and diffusion or GAN-based generators) for spatial structures and downscaling, and (iii) spatiotemporal fusion frameworks that jointly model space–time dynamics. We further summarize hybrid strategies that integrate DL with numerical models through post-processing, emulation, and data assimilation, as well as physics-informed learning that embeds conservation laws or dynamical constraints. Despite rapid advances, challenges remain in generalization under non-stationary climate conditions, dataset shift, and physical consistency (e.g., mass/energy conservation), interpretability, and fair evaluation across regions and lead times. We conclude with practical recommendations for future research, including standardized benchmarks, uncertainty-aware probabilistic forecasting, physics-guided training and neural operators for long-range dynamics, and foundation models that leverage self-supervised pretraining on large-scale Earth observation archives. Full article

Rapid urbanization and spatial constraints in high-density residential areas pose significant challenges to public health and well-being. This study investigates the mechanisms by which the visual environment of urban micro public spaces shapes residents’ psychophysiological responses to encourage spontaneous physical activity and advance active health. Using machine learning and semantic segmentation, 9 core visual elements across 20 micro public space scenes in high-density urban neighborhoods were quantified. An immersive virtual reality (VR) experiment was conducted, collecting synchronized multimodal psychophysiological data from 60 participants, which yielded 600 valid observations. Through an analytical framework combining Self-Organizing Map (SOM) clustering and Random Forest (RF) modeling, three distinct functional archetypes were identified: Restoration-Supporting, Activity-Promoting, and Stress-Inducing. The Activity-Promoting archetype was most effective in fostering spontaneous activity intention, characterized by a high proportion of activity areas, a moderate sky view factor, and minimal physical barriers. RF modeling further pinpointed pedestrian density, activity area ratio, and green space ratio as key visual drivers of health-promoting outcomes. Based on these findings, a “Visual Activation for Active Health” framework is proposed. It posits that moderate visual-environmental stimulation is the core mechanism for transforming passive spaces into health-promotive settings, thereby establishing a theoretical foundation for the evidence-based design of healthy and sustainable urban environments. Full article

As heritage museums shift toward more experience-oriented development, fragmented layouts and discontinuous visitor flows can reduce both spatial efficiency and the coherence of on-site experience. This study proposes an immersive experience-centred evaluation framework for exhibition layout in heritage museums, intended to translate experience goals into practical and diagnosable criteria for spatial optimization. An indicator system was refined through two rounds of Delphi consultation with an interdisciplinary expert panel, resulting in a hierarchical framework comprising five dimensions and multiple indicators. To support intervention prioritization in design and operations, weights were derived using the Group Analytic Hierarchy Process (GAHP), with Aggregation of Individual Judgments (AIJs) and consistency checks applied to control group judgement quality. A CV–entropy procedure was further used to support prioritization at the third-indicator level. Importance–Performance Analysis (IPA) was then employed to convert “importance–fit” assessments into an actionable sequence of optimization priorities. The results indicate that narrative and scene design carries the greatest weight (0.2877), followed by circulation and spatial organization (0.2281), sensory experience and atmosphere (0.1981), authenticity and sense of place (0.1644), and interactivity and participation (0.1217), suggesting that a “narrative–circulation–atmosphere” chain forms the core support for immersive layout design. A feasibility application using the Yinxu Museum demonstrates the framework’s value for benchmarking and diagnosis, helping decision-makers enhance visitor experience while respecting conservation constraints and more precisely target spatial investment priorities. Full article

Retinoic acid receptor (RARγ) mRNA is expressed spatially and temporally during mouse embryogenesis and largely within stem and progenitor cells, indicating a role in organ formation. RARγ agonism promoted the maintenance of hematopoietic stem cells, and blocked stem cell development as shown for hematopoiesis, zebrafish development, and chondrogenesis. Transgene expression enhanced the generation of induced pluripotent stem cells, indicating a role in ground-state pluripotency. RARγ is oncogenic in acute myeloid leukemia, cholangiocarcinoma, and colorectal, head and neck, hepatocellular, ovarian, pancreatic, prostate, and renal cancers. RARγ agonism or overexpression enhanced the proliferation of cancer cells. Conversely, antagonism or inhibition of all-trans retinoic acid synthesis led to the death of cancer cells including cancer stem cells. The pathways regulated by RARγ, via canonical activation and repression of gene expression, include Wnt/β-catenin and Notch signaling. RARγ also acts as a co-factor to Smad3 and reduced or enhanced TGFβ-driven and Smad3-mediated events when liganded and non-liganded, respectively. Collectively the findings support the view that RARγ plays a crucial role in controlling stem and progenitor cell behavior. Full article