Search Results (372)

In the context of low-carbon development targets, urban expansion within the karst ecoregions of southern China has intensified land-use-related carbon-stock losses, which highlights the necessity of scientific and sustainable land-use management strategies. Using multi-temporal land-use datasts spanning six periods from 2000 to 2025, this study integrates carbon-stock accounting and land-use transition-matrix analysis. Multicollinearity testing and spatial autocorrelation analysis are employed to reveal the driving mechanisms behind carbon-stock variations. Based on standardized beta coefficients (β), all driving factors are hierarchically classified into primary dominant factors, secondary constraint factors, and tertiary disturbance factors according to their regulatory intensity, and further grouped into topographic, ecological, and socioeconomic categories. On this basis, three differentiated land-management scenarios are constructed. By coupling the PLUS and InVEST models, this study simulates regional carbon-stock conditions for 2030 and 2035. The results show that regional carbon-stock exhibits a fluctuating pattern: it decreased from 2000 to 2005, rose continuously during 2005–2015 to reach its peak in 2015, and then declined persistently from 2015 to 2025. Spatially, obvious zonal differentiation can be observed: the northwestern mountainous areas maintain high carbon-stock levels, whereas southern coastal towns experience severe carbon-stock degradation. Topographic factors dominate regional carbon-stock dynamics; ecological factors exert critical buffering effects; human-induced land-use activities act as the secondary driver for carbon-stock loss. The conversion of farmland and woodland to construction land represents the major contributor to regional carbon-stock reduction. Under the “2035 Steep-slope Carbon-stock Protection Scenario”, the total regional carbon-stock increases by 1441.69 million tonnes relative to the “2035 Natural Development Scenario”. This scenario achieves the coordinated advancement of rocky desertification control and sustainable land use, facilitates synergistic low-carbon improvement and land-system sustainability, and provides practical references for low-carbon land governance in similar karst regions worldwide. Full article

Coastal zones rank among the most productive, densely populated, and rapidly transforming systems on Earth, yet the very development that sustains them increasingly compromises their long-term viability. Drawing on the international coastal management and marine science literature, this narrative review traces the ways in which human development along the coast drives environmental degradation and, in turn, elicits institutional and ecological responses. It shows that three principal activities—land reclamation, mariculture and marine aquaculture, and urban coastal sprawl—recur as the sources of a recurring suite of environmental harms, spanning shoreline erosion, plastic and heavy-metal pollution, invasive-species incursions, and the loss of blue-carbon habitat. In response, a growing literature documents integrated coastal management, marine functional zoning, carrying-capacity assessment, and climate-adaptive and nature-based solutions as progressively more integrated instruments of governance. The review argues that these three stages form a single development–degradation–response cycle, and that whether that cycle closes constructively depends less on the mere presence of development than on the quality of the governance response it elicits. Across the cases synthesized here, the most acute pressure–degradation couplings arise where rapid urbanization and intensive coastal use coincide with weak or fragmented governance, whereas durable institutions of integrated coastal management and zoning have demonstrably contained or reversed degradation. The review closes by identifying the most pressing research gaps and the policy levers available to decision-makers seeking to reconcile coastal development with sustainability. Full article

Polders are typical semi-artificial and human-dominated ecosystems widely distributed in the middle and lower reaches of the Yangtze River Basin. They serve as important sinks and sources of nitrogen (N) and phosphorus (P) in agricultural watersheds. Long-term intensive human intervention substantially alters the hydrological and biogeochemical processes of polder ecosystems, resulting in complex and uncertain effects on water quality that remain insufficiently understood. This study conducts a systematic literature review and narrative synthesis of evidence on N and P transport in polders across the middle–lower Yangtze River plain. The evidence is derived from field monitoring, plot experiments, and numerical simulations. The review focuses on the spatiotemporal patterns of nutrient variation, sink–source conversion functions of ditches and small ponds, drivers of nutrient loss, and current research bottlenecks under artificial sluice-pump regulation. The synthesized results indicate that polders exhibit a distinctive nutrient transport pattern characterized by dispersed in situ retention under conventional water management and concentrated pulse export during drainage events. Artificial sluice-pump operation drives episodic nutrient export throughout the crop growth period, imposing persistent pressure on the water quality of downstream rivers and lakes. N and P transformations are jointly controlled by natural hydrological fluctuations and human activities. Within agricultural lands of polders, fertilizers account for 73.3% of total nitrogen inputs and 87.9–93.5% of total phosphorus inputs. Crop harvesting and regulated drainage constitute the two dominant pathways for nutrient export. Hydraulic regulation prolongs water residence time in polder ditches and ponds, resulting in retention efficiencies of 52–65% for allochthonous N and P. However, seasonal flooding and waterlogging can induce sediment hypoxia and endogenous nutrient release, thereby causing secondary internal pollution and increasing the eutrophication risk of adjacent receiving water bodies. Three major research gaps are identified: insufficient long-term continuous multi-indicator monitoring data, limited model applicability for simulating human-regulated hydrology–nutrient coupling, and poorly defined critical thresholds for polder sink–source functional reversal. This regional systematic review advances the understanding of human–hydrology–nutrient coupling mechanisms in Yangtze River polder systems. It also provides targeted theoretical support for agricultural non-point source pollution mitigation and water environment management in floodplain agricultural areas. Full article

In the central nervous system, the neuropeptide oxytocin stimulates neural networks that regulate social behaviors, including social attachment, aggression, and complex social cognition. Perturbations in oxytocin and/or oxytocin receptor expression results in social behavioral deficits and are associated with a number of psychopathologies including autism spectrum disorder, schizophrenia, anxiety, and depression. In rodent models of autism spectrum disorder, oxytocin is effective at improving social behavior. However, limited translatability between animal models and human physiology has hindered successful translation of these findings into human therapeutics. Oxytocin variant-induced cellular signaling pathways and G-protein coupling have largely been investigated in HEK and CHO heterologous expression systems; however, cellular context is crucial, and these profiles likely differ from intact neurons. This project assessed oxytocin variants in in vitro human-derived neuron-like SH-SY5Y cells that endogenously express the oxytocin receptor. Results demonstrated that the naturally occurring oxytocin variants Leu⁸-OT, Pro⁸-OT and Val³-Pro⁸-OT activated intracellular signaling pathways and promoted neuronal differentiation-associated responses, including calcium mobilization, membrane hyperpolarization, and neurite outgrowth in a concentration-dependent manner. Knowledge of how oxytocin variants alter cellular structure and function has the potential to both identify mechanisms that produce social dysfunction and to inform the development of therapeutic agents. Full article

In an increasingly globalizing world, invasive species have become a serious concern worldwide. Numerous studies have focused on the biology of different invasive species, but few have systematically integrated socioeconomic and environmental factors. The framework of telecoupling (socioeconomic–environmental interactions over distances) can help address this challenge by allowing researchers to integrate human-nature interactions across distances. To demonstrate this potential, the framework was applied to the invasion of the Burmese python (Python bivittatus) from Southeast Asia. This species is a large constrictor currently invading the Greater Everglades ecosystem in South Florida, USA, through the pet trade. Results show many causes and effects of the invasion. The analysis also exposes several research gaps. The most prevalent is a lack of published research about the species’ native range, including biology in the wild as well as a socioeconomic understanding of the people involved in and affected by the invasion. The telecoupling framework connects scattered information, providing insights into flow-centered management approaches that could lead to more effective population control. This analysis shows the telecoupling framework’s potential to improve understanding of the complexities of invasive species, their causes, effects, future research directions, and management strategies. Full article

Inappropriate concentrations of elements in formulae for infants may lead to adverse health effects. Selenium (Se) is a trace element essential for the proper development of infants. It is naturally present in human milk and is also added to infant formulae. However, both insufficient and excessive Se intake may be harmful. The aim of this study was to determine Se concentrations and chemical forms in 148 formulae for infants available on the Polish market and to assess their nutritional safety. Se concentrations were determined using inductively coupled plasma mass spectrometry (ICP-iCRC-MS). Se speciation was performed using a HPLC system coupled to ICP-iCRC-MS. The Se concentrations in most analyzed formulae were in good agreement with the recommended EU limits (median 4.5 µg/100 kcal, range 0–15.6 µg/100 kcal). However, the estimated daily intake for 6-month-old infants exceeded the tolerable upper intake level in six formulae, indicating a potential health risk. Speciation analysis showed that the dominant Se forms were sodium selenite and sodium selenate, and their levels were mostly consistent with the manufacturers’ declarations. Additionally, trace amounts of selenometionine (SeMet) and methyloselenocysteine (MeSeCys) were detected. Therefore, regular monitoring of the composition of infant formulae remains necessary. The detection of SeMet and MeSeCys provides new avenues for research on Se content and Se speciation in formulae intended for infants. Full article

Pedestrian-induced vibration is a critical serviceability concern for flexible structures such as footbridges and long-span floors. Existing human–structure interaction models commonly rely on single-degree-of-freedom simplifications and time-domain simulations, making them less suitable for frequency-domain analysis. This paper proposes a spectral analysis model for crowd-structure interaction vibration under unrestricted pedestrian traffic. The structure was formulated as a multi-degree-of-freedom modal system, whereas each pedestrian is represented by an independent spring–mass–damper system. To address the time-varying nature of moving crowds, a piecewise stationary assumption was introduced: the continuous walking path was discretized into fixed position groups, within each of which a time-invariant coupled equation of motion was established. The response spectra obtained for different position groups were combined using residence-time weighting, thereby allowing nonuniform walking speeds to be considered. The corresponding frequency response function was derived using the state–space method, and the structural acceleration power spectral density and root mean square responses were obtained by incorporating an unrestricted crowd walking load spectral model. Comparisons with field measurements from two footbridges demonstrated reasonable agreement. The resulting framework offers an efficient frequency-domain approach for vibration serviceability assessment under unrestricted pedestrian traffic. Full article

Doppler Light Detection and Ranging (LIDAR) systems and a mesoscale meteorological model coupled with computational fluid dynamics (CFD) for the monitoring of low-level wind and turbulence have been extensively applied for the Hong Kong International Airport. This study represents the first application in Hong Kong to apply such techniques for the exploration of providing meteorological support for the operation of Unmanned Aircraft Systems (UASs) in a sandbox project in Hong Kong. The flight route under consideration is between the western coast of Hong Kong Island and an outlying island called Lamma Island, with a sea channel in between. Based on the LIDAR observations in three different prevailing wind directions, low-level turbulence may arise from wind flow disruptions by natural terrain and human-made buildings. Simulations of the wind and turbulence are attempted using the GPU-based FastEddy, with the turbulent kinetic energy equation being used to output the eddy dissipation rate (EDR). Comparisons between observed and simulated fields showed broadly consistent patterns across wind speed, wind direction, and EDR. Quantitative validation yielded RMSE of 1.35 m/s for wind speed, 28.4° for wind direction, and 0.032 m²/s² for EDR, with corresponding R² values of 0.72, 0.48, and 0.07, respectively. However, point-to-point comparison as in the scatter plot of the two datasets is still challenging, due to low correlation for EDR. Nonetheless, FastEddy is found to shed preliminary insights to generate reasonable simulations of low-level winds and turbulence to support the operation of UASs for the cases under study. These findings should be considered preliminary and exploratory given the limited number of case studies analyzed. More cases would need to be studied to find out the performance of FastEddy in other meteorological conditions. Full article

Initially identified as a hormone linking obesity to insulin resistance, resistin is now recognized as a pleiotropic mediator whose cellular sources and biological functions differ substantially between humans and rodents. Beyond its established roles in metabolic dysfunction and inflammation, emerging evidence suggests that resistin may contribute to tissue remodeling and fibrosis in a context-dependent manner. This review critically synthesizes mechanistic, translational, and clinical evidence across the heart, liver, lung, and kidney. Reported interactions with candidate receptors or binding partners, including adenylyl cyclase-associated protein 1 (CAP1) and Toll-like receptor 4 (TLR4), link resistin-associated signaling to inflammatory, oxidative-stress, and profibrotic pathways that can influence fibroblast activation, hepatic stellate cell responses, extracellular matrix production, and structural tissue remodeling. However, the strength and nature of the available evidence differ markedly among organ systems. Direct profibrotic effects are most strongly supported in cardiac experimental models and selected hepatic systems, whereas pulmonary mechanistic evidence is derived largely from studies of other RELM/FIZZ family members, particularly RELMα/FIZZ1 and RELMβ/FIZZ2, rather than human resistin itself, and renal evidence remains predominantly associative. We, therefore, propose a mechanistic paradigm shift that expands, rather than replaces, the established inflammatory role of resistin. Within this framework, the “fibrotic switch” is presented as a unifying hypothesis whereby persistent resistin-associated signaling may couple chronic inflammatory and metabolic stress to progressive fibrogenic remodeling, requiring further organ-, species-, and cell-specific validation. Defining the relevant cellular sources, receptors, and causal pathways will be essential for evaluating resistin as a biomarker and potential therapeutic target in fibrotic disease. Full article

The rubber tree is the world’s main source of natural latex. However, the latex extraction and harvesting system requires a high level of human labor with agricultural tractors, which can expose workers to adverse conditions, such as noise. This study focused on evaluating the noise level emitted by an agricultural tractor during rubber harvesting at different operating points and working speeds. The experimental design adopted was completely randomized in a two-factor factorial arrangement with six replications. The treatments consisted of two tractor engine speeds (900 and 1500 rpm) and two workstation positions (worker inside the tractor and inside the transport trailer) during the latex coagulate collection. For the harvesting operations, a Massey Ferguson model 265 tractor coupled with a transport trailer noise exposure were used during the following operations: 1—distribution of boxes between the rows of rubber trees; 2—loading of the boxes with the collected coagulate; 3—transport of the boxes with latex coagulate to the storage location for commercialization; 4—unloading of the boxes at the storage location for commercialization. Noise assessments were performed at the workers’ ear level using a decibel meter according to technical standards. The workers’ positions and the tractor’s engine speed influenced the noise level during latex coagulate harvesting. The highest noise levels were observed when the agricultural tractor operated at a higher engine speed (1500 rpm), compared to 900 rpm engine speed. Regarding the workstation position, it was found that the noise level at the tractor operator’s station was higher than the noise level at the trailer workers’ station in all harvesting operations. Full article

Spatiotemporal differentiation and coupled driving mechanisms of urban ecological resilience in transboundary composite economic belts remain an understudied niche within human–land coupling system research. Taking 29 prefecture-level and county-level units of the Huaihe River Eco-Economic Belt from 2014 to 2023 as research samples, this study constructs an ecological resilience evaluation framework tailored to the pollution disturbance characteristics of the Huaihe River Basin under a three-dimensional theoretical framework encompassing resistance, adaptability, and recoverability. The entropy weight method is adopted to calculate comprehensive ecological resilience values, while the geographically and temporally weighted regression (GTWR) model is applied to identify spatiotemporal heterogeneous correlations among multiple influencing factors. This paper further characterizes the spatiotemporal evolutionary patterns of urban ecological resilience across the study area and unpacks the coupled associative effects of natural, economic, and social driving factors. The empirical results reveal three key findings: (1) Temporally, the overall comprehensive ecological resilience of the study region rose from 0.318 to 0.416, with a total growth rate of 30.91%. Its evolutionary trajectory follows three successive phases: rapid growth, steady improvement, and slow saturation. Adaptability, which is predominantly boosted by anthropogenic environmental governance, constitutes the primary contributor to resilience growth. The range of urban resilience values narrowed by 9.97%, indicating continuous advancement in balanced regional development. (2) Spatially, ecological resilience presents a prominent core-periphery pattern, with high-resilience zones concentrated in mountainous southwestern areas and low-resilience zones distributed across northeastern plains. All low-resilience county-level units were eliminated by 2023. (3) In terms of driving associations, topographic relief and environmental governance investment maintain persistent positive correlations with ecological resilience, while per capita GDP acts as the core economic supportive factor. The proportion of secondary industry and population density exhibit significant negative correlations with resilience. The normalized difference vegetation index (NDVI) shifts from a negative correlation to a weak positive correlation alongside progressive ecological restoration, whereas river network variables exert negligible long-term associative impacts. Collectively, the spatiotemporally heterogeneous coupling of natural endowments, industrial-economic conditions, and social governance factors shapes the evolutionary patterns of regional ecological resilience. This study fills the research gap regarding long-timescale resilience driving mechanisms for transprovincial composite river basins covering five provinces. It identifies novel human–land coupling mechanisms, including the temporal reversal of vegetation’s ecological benefits and the dual stress imposed by industrial agglomeration and dense human settlements in plain regions. The quantitative outputs of this research can provide data-based references for differentiated coordinated ecological governance across the Huaihe Ecological Economic Belt. Full article

Freshwater resources constitute a fundamental component of coupled natural–human systems, underpinning ecosystem functioning, biogeochemical cycling, and socio-economic development. Anthropogenic climate change (i.e., climate change attributable to human activity, as distinct from natural climatic variability), driven primarily by greenhouse gas emissions and land-use change, is exerting significant pressure on the global hydrological cycle, resulting in increased hydroclimatic variability, intensification of extreme hydrometeorological events, and progressive degradation of freshwater quality and availability. This review synthesizes recent scientific evidence on climate-induced impacts on water systems together with emerging adaptation and resilience strategies. The analysis is based on a systematic assessment of 100 peer-reviewed studies indexed in the Web of Science Core Collection (2010–2025) and synthesized following a PRISMA-informed (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) narrative review protocol. Beyond confirming well-established trends in precipitation regimes, cryospheric decline, increasing evapotranspiration, and the growing frequency of droughts and floods, this review quantifies the magnitude of these changes across the reviewed literature, including an approximately 134% increase in flood-related disasters since 1980 and a 29% increase in drought duration since 2000. More importantly, it provides an integrated synthesis that links physical climate impacts with adaptation strategies and socio-ecological resilience frameworks within a unified analytical perspective, thereby complementing previous domain-specific reviews that have generally examined these dimensions separately. Prominent adaptation pathways identified across the reviewed literature include nature-based solutions, integrated water resources management frameworks, and the deployment of digital water technologies. In parallel, resilience is increasingly conceptualized as the adaptive capacity of socio-hydrological systems to absorb disturbances, reorganize, and transform under changing climatic conditions. The findings highlight the need to strengthen integrated and cross-sectoral water governance, enhance climate-informed decision-making, and expand monitoring and data infrastructures to improve long-term water security and socio-ecological resilience under accelerating climate change. Full article

Stationary human–structure interaction (HSI) can significantly modify the vibration characteristics of lightweight structures, yet it remains unclear whether a human model identified for an individual can be extended consistently to crowd conditions. This study investigates this issue through sweep-frequency tests on a single-degree-of-freedom (SDOF) rig under single-person standing, single-person seated and two- to five-person standing group conditions. The measured acceleration frequency response functions (FRFs) were fitted using a two-degree-of-freedom (2DOF) integrated HSI model to identify equivalent human/crowd and structural parameters. The experimental program involved 20 participants and 180 tests, yielding 40 averaged individual datasets and 50 averaged group-combination datasets. Clear double-peak FRF characteristics were observed under all occupied conditions, indicating coupled 2DOF behavior rather than a simple added-mass effect. Compared with seated occupants, standing occupants showed a slightly higher equivalent human natural frequency (6.76 Hz versus 6.45 Hz), but lower human damping ratio (23.37% versus 31.73%) and body mass ratio (BMR) (0.621 versus 0.729). For standing groups, the equivalent crowd damping ratio increased from 24.60% for the two-person group to 29.10% for the five-person group, and BMR increased from 0.66 to 0.80, whereas the equivalent crowd natural frequency remained within 6.74–7.02 Hz. These results support a unified but parameter-dependent 2DOF framework for stationary individuals and crowds, provided that posture- and crowd-dependent parameters are identified from the overall coupled-system FRF rather than obtained by direct averaging of individual properties. Full article

Innovation-oriented productive forces are increasingly concentrated in cities, but the multiscale mechanisms through which the built environment shapes these forces remain insufficiently understood. This study develops a spatial analytical framework linking firm-level new quality productive forces (NQPF) to fine-grained urban spatial structures. Using 89 A-share listed firms in the Xiamen–Zhangzhou–Quanzhou (XZQ) urban agglomeration, we first construct an entropy-weighted NQPF index from eleven financial indicators related to R&D human capital, advanced capital stock, intangible assets, and operational efficiency. Kernel density estimation is then used to transform discrete firm-level NQPF values into a continuous 600 m × 600 m grid surface as the dependent variable. On the explanatory side, 27 built-environment variables are organized into an integrated indicator system covering urban form, natural conditions, jobs–housing structure, and service infrastructures. We combine cross-validated recursive feature elimination (RFE-CV) with multiscale geographically weighted regression (MGWR) to construct two model specifications: a 7-variable parsimonious subset and a 14-variable highest-performing subset. This dual-subset design allows us to distinguish core structural drivers from more context-dependent spatial mechanisms. The results reveal three mechanisms. First, ecological adaptation reflects the scale-dependent enabling and constraining effects of infrastructure and natural-foundation variables. Second, structural coordination shows that mature cores may experience crowding-related suppression when functional and institutional resources become spatially mismatched. Third, boundary activation indicates that transport, public-service, and leisure-related facilities can activate peripheral and cross-jurisdictional interface zones when supported by network connectivity and institutional coordination. By coupling variable-specific bandwidths with local coefficients, this study advances the analysis of spatial heterogeneity and provides evidence for differentiated, innovation-oriented urban regeneration. Full article

This study developed an eco-epidemiological model incorporating constant prey refuge, predator disease transmission, and anthropogenic harvesting to explore the coupled dynamical behaviors of ecological populations under natural infection and human interference. All feasible equilibrium points of the proposed system were solved, and the local stability of the boundary equilibria and threshold conditions for transcritical bifurcations were systematically analyzed. The global asymptotic stability of the positive coexistence equilibrium was verified by constructing the appropriate Lyapunov functions. Furthermore, a parameter sensitivity analysis was performed to identify the dominant parameters governing population persistence and system stability. To balance ecological sustainability and economic benefits, an optimal harvesting control problem was investigated, and time-dependent optimal harvesting efforts were obtained by applying optimal control theory. Numerical simulations demonstrated that the optimal harvesting strategy can dynamically adjust the harvesting intensity to maximize long-term discounted economic profit while maintaining stable population coexistence. The theoretical and numerical results provide reliable theoretical guidance for the sustainable exploitation and ecological management of infected predator–prey ecosystems. Full article