Search Results (308)

Terrestrial ecosystems play a critical role in achieving carbon neutrality, yet the carbon sequestration potential (CSP) of China’s terrestrial ecosystems remains incompletely characterized, particularly regarding the roles of future climate scenarios and land–atmosphere moisture feedbacks. Here we quantify China’s CSP using a process-based model (LPJ-GUESS) that explicitly simulates vegetation dynamics, combined with potential natural vegetation (PNV) benchmarks and moisture recycling. We estimate China’s historical (1993–2022) actual terrestrial (AT) carbon stock at 91.7 PgC, with a PNV ceiling of 132.9 PgC, yielding a CSP of 41.2 PgC. Under future scenarios (2071–2100), CSP follows a non-linear trajectory. Relative to the historical baseline, it declines slightly under SSP119, peaks under SSP2-4.5, and remains elevated but slightly reduced under SSP5-8.5. High-CSP areas are concentrated along the Hu Line and the belts of the Tianshan, Kunlun, and Qilian mountains, while scattered areas in southern China exhibit negative CSP due to intensive human interventions. Moisture recycling consistently enhances CSP across all periods and scenarios. Historically, it raised national CSP by approximately 5 PgC, and this enhancement gradually weakens to 4 PgC under SSP119 and further declines to around 2 PgC under SSP2-4.5/SSP5-8.5—revealing that high emissions erode this positive feedback. Our findings identify a critical window for maximizing restoration gains under moderate forcing (SSP2-4.5) and demonstrate that low-to-moderate emission pathways not only preserve direct carbon benefits but also safeguard indirect moisture recycling amplification. Regionally tailored restoration strategies accounting for moisture recycling are essential for achieving China’s 2060 carbon neutrality goals. Full article

The spatial allocation of urban road infrastructure directly affects urban operational efficiency, social equity, and ecological environmental quality. Taking 36 major Chinese cities as the research subjects and drawing on data from municipal statistical yearbooks, this study employs a composite index method, Theil index decomposition, and correlation analysis to reveal spatial differentiation patterns, imbalances, and driving factors of urban road infrastructure levels, based on both aggregate and average indicators. The results indicate that the aggregate road infrastructure level exhibits a “high in the southeast, low in the northwest” pattern along the Hu Huanyong Line, while the average road infrastructure level reveals relatively lower performance in some first-tier cities. Imbalances exist in both aggregate and average dimensions, with Theil indices of 0.231 and 0.059, respectively; intra-regional disparities contribute more to total inequality than inter-regional disparities. Urban permanent population (ridge regression coefficient: 0.1991) and fiscal revenue (ridge regression coefficient: −0.1087) are the core driving factors among the four influencing factors of aggregate road infrastructure level spatial differentiation, whereas GDP (−0.0318) and built-up area (0.0703) exert only marginal effects. This suggests that current aggregate urban road infrastructure levels are shaped by the interplay of urbanization stage, economic development level, fiscal system, and spatial planning policies, all operating within the constraints imposed by the city’s natural geographical conditions, and have not yet adequately addressed residents’ demand for spatial equity. The study recommends establishing differentiated investment mechanisms, optimizing road network density in developed cities, and constructing a spatial matching early-warning system to promote people-oriented new urbanization and coordinated regional sustainable development. Full article

Background/Objectives: Advanced-stage hepatocellular carcinoma is characterized by a very poor prognosis; thus, highly effective medication is still needed. Often overexpressed heat shock protein 90 is a promising target due to its pivotal role in carcinogenesis. Methods: Antiproliferative effects of 246TMP-3SF5 on HepG2 and HuH-7 cells were assessed by crystal violet staining. Apoptosis was evaluated via subG1 peak, caspase-3 activity and PARP cleavage, and ferroptosis via ROS, glutathione and malondialdehyde levels. Migration was assessed by scratch assay, and in ovo models were used to study angiogenesis and drug effects on microtumors. CAM vascular networks were quantified by semi-automatic segmentation, morphometric and box-counting fractal analysis. Molecular docking and molecular dynamics simulation of heat shock protein 90 were carried out using Autodock Vina and Gromacs respectively. Results: Profound dose- and time-dependent antiproliferative effects of 246TMP-3SF5 against HCC cell lines were observed, revealing low micromolecular IC₅₀ values and selectivity for carcinoma cells with selectivity indices > 1. A significant increase in the sub-G1 peak, key effector caspase-3 activity, as well as cleavage of PARP strongly suggested apoptosis playing a crucial role in the antiproliferative effects. Additionally, HuH-7 cells revealed an elevation of reactive oxygen species and both cell lines showed significant glutathione depletion concomitant with an increase in malondialdehyde concentration upon treatment. The observed effect could be partially reversed by applying ferrostatin-1, suggesting ferroptosis as an additional relevant mode of action. Changes in the cell cycle as well as impaired tumor cell migration were observed. Upon treatment, angiogenesis was impaired and mass of microtumors was significantly reduced. Quantitative CAM analysis showed that vascularized area fraction increased in controls but decreased under both 17-AAG and 246TMP-3SF5. Likewise global mean vessel width decreased relative to controls, while box-counting dimension was reduced under 246TMP-3SF5. Molecular docking and molecular dynamics simulation analysis predicts 246TMP-3SF5 to be binding in catalytic site of heat shock protein 90. Conclusions: 246TMP-3SF5 is a promising novel inhibitor meriting further research as a potential treatment against hepatocellular carcinoma. Full article

High-fat diets may improve energy supply in laying hens, but they can also increase fat deposition in the liver and contribute to fatty liver hemorrhagic syndrome (FLHS), a metabolic disorder that impairs hen health and egg production. Bile acids (BAs), which are natural compounds produced in the liver to support fat digestion and metabolic regulation, may help reduce these negative effects. This study evaluated the effects of dietary BA supplementation on production performance, selected egg quality traits, lipid-related indices, liver histology, and cecal microbiota in late-phase laying hens fed a high-fat diet (HFD). A total of 150 Hy-Line Brown laying hens at 50 weeks of age were allocated either a normal diet (ND), a HFD, or a HFD supplemented with 300 mg/kg BAs (HFD + BAs) for 5 weeks. Compared with the HFD group, BA supplementation affected average daily feed intake (ADFI) and increased the Haugh unit (HU) (p < 0.05), whereas laying rate (LR), average egg weight (AEW), feed conversion ratio (FCR), and most other egg quality traits were not significantly changed. BA supplementation was also associated with differences in selected serum and hepatic lipid-related indices. Histological observations indicated differences in hepatic lipid deposition among treatments. Cecal microbiota analysis showed treatment-associated differences in microbial composition, and correlation analysis identified associations between selected taxa and lipid-related indices. These results indicate that, under the present HFD conditions, dietary BAs were associated with changes in selected egg quality traits, hepatic lipid-related indices, and cecal microbial composition. These findings indicate that dietary BAs may improve selected egg quality traits and liver health in late-phase laying hens by regulating lipid metabolism and intestinal microbiota. Full article

As a new generation of general technology, artificial intelligence (AI) provides crucial technical support for addressing the dilemmas of carbon emission reduction in cities. This paper selects data from 273 prefecture-level cities in China from 2010 to 2024 to examine the impact of AI on urban carbon emission intensity (CEI) and its mechanism of action. The results show that AI is negatively associated with CEI. AI lowers the threshold for scientific research, expands the scale of patent output, and generates groundbreaking high value patents, which indicates that both the quantity and quality of innovation are key paths to facilitating urban carbon emission reduction. The results of the heterogeneity test indicate that the carbon reduction effects of AI exhibit stratified characteristics, with cities southeast of the Hu Line, northern industrial cities, and resource-based cities demonstrating more prominent emission reduction effects. Accordingly, policy recommendations such as establishing regional digital low-carbon layouts and allocating policy resources based on resource endowments are put forward. The research provides a theoretical basis for reducing carbon emissions and achieving sustainable development goals relying on AI. Full article

This paper discusses the dynamic mechanism of stability and the possibility for breakthrough of the Hu Line based on the relationship between population, socioeconomic development and the environment. Against the background of sustainable development and climate change, we used historical census data from China and comparative analysis of three versions (IIASA, NUIST and Tsinghua) of the Shared Socioeconomic Pathways (SSPs) to analyze multidimensional demographic characteristics such as population size, age and education on both sides of the Hu Line (China’s population boundary). The study found that SSP scenarios and regional differences in the natural growth rate (defined by fertility and mortality) and urbanization rate jointly influenced the changes in the proportion on both sides of the Hu Line. In addition to the breakthrough of the population proportion on the west of the Hu Line, population quality deserves greater attention. The provinces on the east and west sides of the Hu Line can adopt different social and economic development paths to achieve sustained development of the population, economy, society, resources and environment. On the premise of sustained social and economic development, the total population will not rise or fall significantly, keeping the trend of aging under control, and enhancing the educational level. The central government should increase investment in basic education in the provinces west of the Hu Line and create more employment opportunities through the Belt and Road Initiative and the new urbanization strategy. In areas with abundant water resources on the west of the Hu Line, urbanization efforts should be rationally planned and advanced to gradually establish clusters of talent hubs. This will facilitate the effective conversion of human resources by retaining and attracting higher-education professionals to pursue employment and entrepreneurship opportunities. Full article

Fanconi anemia (FA) is a rare disease with a deficient homologous recombination DNA repair pathway and high sensitivity to mitomycin C (MMC). In FA cells, hydroxyurea (HU), when applied in the G2 phase of the cell cycle, exacerbates the chromosomal aberrations (CAs) induced by MMC. Here, we study how exposure to HU in the G2 phase results in an increased CAs frequency in FA cells with or without prior treatment with MMC. We performed chromosome aberration analysis, flow cytometry, and mRNA and protein expression in lymphoblastoid cell lines. We found that HU alone induces post-replicative DNA damage in the form of DNA double-strand breaks (DSBs) in both wild-type and FA cells and a similar increase in the activation of DSBs marker ɣH2AX. HU potentiates the amount of CAs only in MMC-treated FA cells by multiple mechanisms, including (1) hindering the ɣH2AX signal, (2) impairing the translocation of ribonucleotide reductase (RNR) into the cell nucleus, and (3) promoting the activity of WIP1 phosphatase. Concomitantly, increased levels of cell death were observed in FA cell cultures. HU induces DNA damage and potentiates pre-existent damage in FA cells by preventing the translocation of the RNR component p53R2 into the nucleus and activating checkpoint recovery, thus allowing the survival of a proportion of FA cells that have adapted to DNA damage. Full article

Urban sustainability depends not only on environmental efficiency but also on cities’ capacity to withstand ecological shocks, maintain essential services, and adapt to long-term resource constraints. This study examines whether the intelligent economy strengthens urban green resilience, a key foundation of sustainable urban development. Using a balanced panel of 273 Chinese prefecture-level cities from 2013 to 2023, we construct entropy-weighted indices and apply two-way fixed-effects, instrumental-variable, mechanism, heterogeneity, and spatial models. A one-standard-deviation increase in the intelligent-economy index is associated with a 0.205-standard-deviation increase in urban green resilience, and the result remains robust across alternative samples, variable treatments, machine-learning estimation, and instrumental-variable specifications. Digital inclusive finance and industrial structure rationalization partially transmit this effect. The gains are greater in cities with stronger human capital, stricter environmental mandates, locations southeast of the Hu Line, and closer access to fiber-optic backbone nodes. Spatially, adjacent-city development generates a negative conditional neighboring effect, whereas the feedback-adjusted indirect effect is positive, with significant diffusion within 200 km and a non-monotonic pattern across distance bands. These findings show that intelligent development supports urban sustainability when technological capacity is converted into inclusive finance, coordinated industrial transformation, effective governance, and regionally shared resilience. Full article

New-quality productive forces provide an important conceptual lens for understanding how innovation-driven development, digital empowerment, and the green transition jointly support sustainable regional development. From a geographical perspective, this study develops a multidimensional evaluation system for new-quality productive forces based on the three elements of productive forces: laborers, means of labor, and objects of labor. Using panel data for 31 provincial-level administrative units in China from 2012 to 2022, we integrate the entropy weight method, standard deviation ellipse, exploratory spatiotemporal data analysis, the obstacle degree model, and the random forest model to examine the spatiotemporal evolution and influencing mechanisms of new-quality productive forces. The results show that: (1) China’s new-quality productive forces increased steadily during the study period, but their overall level remained relatively low and regional disparities continued to widen. Spatially, they exhibited a pronounced “high in the east and low in the west” pattern, with South China and East China maintaining leading positions and Guangdong and Jiangsu forming a dual-core growth structure. (2) The spatial center of gravity remained southeast of the Hu Huanyong Line, and its expansion direction was broadly parallel to this line, indicating a relatively stable spatial configuration. The ESTDA results further reveal significant positive spatial autocorrelation, strong temporal inertia, and marked path dependence in local spatial transitions. (3) High-tech talent supply, innovation and entrepreneurship vitality, and ecological governance capacity constitute the main internal bottlenecks constraining the development of new-quality productive forces. The analysis of external factors indicates that economic scale and population size are the primary predictors of NQPF development, whereas government intervention, openness, urbanization, and industrial structure exhibit varying degrees of nonlinearity and regional heterogeneity. These findings enrich the geographical interpretation of new-quality productive forces and provide empirical evidence for formulating differentiated regional innovation policies and productivity transformation strategies. Full article

Using panel data from 282 prefecture-level and above cities in China, this study employs a difference-in-differences (DID) model to examine the impact of the National Sustainable Development Plan for Resource-Based Cities on carbon emission efficiency, as well as its underlying mechanisms and heterogeneous effects. The results indicate that the implementation of the Plan significantly improves carbon emission efficiency. This conclusion remains robust after a series of robustness tests, including the propensity score matching difference-in-differences (PSM-DID) approach. Mechanism analysis further reveals that technological innovation, industrial upgrading, and reductions in energy consumption constitute the primary channels through which the Plan enhances carbon emission efficiency. In addition, economic growth pressure and the degree of marketization exert negative and positive moderating effects, respectively, on the relationship between the Plan and carbon emission efficiency. Heterogeneity analysis shows that the positive effect of the Plan is significant only in resource-based cities located in eastern China, southern China, or southeast of the Hu Huanyong Line. In terms of city size, the positive effect is observed only in medium-sized cities and Type II large cities. Full article

Apolipoprotein A1 (APOA1) and paraoxonase 1 (PON1) are key proteins of high-density lipoproteins (HDL). The aim of the present study was to obtain and characterize an in vitro model for endogenous APOA1 and PON1 longstanding upregulation in hepatocytes that can be further used to decipher the mechanisms of their protective action. Cultured human hepatocytes (HuH-7 cell line) were transfected with CRISPR/dCas9 activation plasmids targeting APOA1/PON1 genes. Following selection with specific antibiotics, RNA sequencing was used for the transcriptomic characterization of the transfected hepatocytes. The functionality of the secreted APOA1/PON1 was evaluated as the capacity of the conditioned medium (CM) from transfected HuH-7 to modulate the oxidative and inflammatory stress in TNFα-activated primary human umbilical endothelial cells (HUVEC). The results showed that: (1) a robust, longstanding upregulation (46 days) of endogenous APOA1/PON1 was obtained after CRISPR/dCas9 transfection and antibiotics selection; (2) APOA1/PON1 upregulation led to a modified transcriptomic profile and increased the expression of several antioxidant genes in transfected hepatocytes as demonstrated by RNAseq analysis; (3) secreted APOA1/PON1 were functional as demonstrated by the CM ability to reduce the levels of reactive oxygen species and inflammatory markers (VCAM-1, MCP-1) in TNFα-activated HUVEC. In conclusion, we achieved an experimental model of successful longstanding upregulation of endogenous APOA1 and PON1 in human hepatocytes. The targeted proteins are secreted in a functional form and can be used for deciphering their complex mechanism of protective action in various pathological conditions. Full article

The phrase “simply do not divine, that is all there is to it” (bu zhan er yi yi 不占而已矣) attributed to Confucius in the Analects has long puzzled scholars in terms of understanding the Yijing. This study reexamines the proposition through a systematic analysis of the Yijing’s cosmology, moral constraints, and cultivation practices. Drawing on the Yizhuan (Ten Wings) and successive commentaries from Han to Song scholars, the paper argues that divination in the Yijing is founded on a cosmological principle: the Yi matches Heaven and Earth, so the hexagram and line images can mirror the order of the cosmos. However, divination is also governed by three moral constraints: jing 敬 (reverence), fu 孚 (sincerity/trust/correspondence), and zhen 貞 (upright steadfastness), which transform it from a technical operation into a discipline of purifying the heart/mind (xin 心). The core finding is that constant virtue (heng de 恒德) renders formal divination unnecessary: when a person cultivates constancy to the point where every action spontaneously accords with the dao of Heaven, the external tools of yarrow and tortoise are transcended. This state is described as “not divining yet divining” (bu zhan er zhan 不占而占). The Yizhuan’s phrase “Be shen 神 to grasp the ineffable and to illuminate spiritually, it is to be sought in the men (who use it)” (shen er ming zhi, cun hu qi ren 神而明之，存乎其人) captures the internalization process through which the practitioner embodies the cosmic order. The study concludes that Confucius’s remark is not a slogan that transforms divination into philosophy but the Yijing’s own highest teaching: the goal of studying change is to become a person who no longer needs to consult the Yijing, because every step is already in rhythm with Heaven and Earth. This interpretation clarifies the Yijing’s distinctive moral philosophy, which neither negates divination nor reduces it to technique, but points toward a form of self-transcendence where the bridge of divination becomes the ground on which one walks. Full article

Understanding the spatial hierarchy, distribution patterns, and driving mechanisms of A-level tourist attractions is essential for optimizing tourism resource allocation and promoting sustainable regional development. This study integrates core–periphery theory with a sustainability perspective to examine hierarchical differentiation of China’s A-level tourist attractions, using 15,699 POI data points collected in 2024 and applying the nearest neighbor index (NNI), kernel density estimation, spatial autocorrelation analysis, and the geographical detector model. The results indicate that these attractions exhibit an unbalanced spatial distribution characterized by a “dense east and sparse west” pattern, with the Hu Huanyong Line (Hu Line) as an important spatial boundary, showing east–west hierarchical disparities. The attractions demonstrate a clustered distribution pattern, although the degree of agglomeration decreases as attraction grades increase. Spatial associations exhibit a pattern of coordination in eastern regions and polarization in western regions, forming a three-tier spatial hierarchy of core–sub-core–periphery. Population density exhibits the strongest explanatory power. Interaction detector results reveal grade-dependent differences. 2A attractions show weak factor associations, whereas 5A attractions are more strongly linked to resource endowment, population density, and economic development. These findings advance the theoretical understanding of the hierarchical spatial structure and differentiated development mechanisms of tourist attractions. Full article

In order to promote the coordinated development of land use and energy equity, this study empirically examines the impact of land use on energy equity and its underlying mechanisms, using panel data from prefecture-level cities in China. The main findings are as follows: (1) An increase in land use intensity significantly hinders the development of energy equity. After a series of robustness checks and endogeneity treatments, this conclusion is still reliable. (2) Population agglomeration, energy consumption intensity, green innovation, and government intervention are the main pathways through which land use affects energy equity. (3) Small and medium-sized cities, resource-based cities, eastern China, and areas north of the Hu Line are where this negative effect is primarily concentrated. These results offer important policy recommendations for the coordinated governance of land use and energy equity. Full article

Optical modules serve as the core transmission interfaces for artificial intelligence computing networks and digital communications. In recent years, demand for these modules has experienced explosive growth. During mass production, the requirements for the accuracy of surface defect detection and noise resistance have continued to rise. Existing POL detection models are susceptible to environmental noise interference; effective defect information is easily overwhelmed by noise entropy, and these models exhibit a high false negative rate for low-contrast and minute defects. This paper proposes a traditional image processing detection scheme that incorporates information entropy constraints. All experimental samples were collected from actual industrial mass production lines. The core process includes: noise suppression during the calibration stage using an entropy-weighted Hough transform; Canny edge detection combined with local entropy filtering for contour localization; and defect fusion recognition based on Hu similarity matching and entropy difference verification. Experimental results show that, compared to traditional POL methods, the proposed approach (WOMC) achieves an average improvement of 35.77% in image clarity and approximately a 2.25-fold increase in detection rate under Gaussian and salt-and-pepper noise conditions. According to statistical analysis of the experiments, this method achieved an accuracy of 96.67%, a recall rate of 97.32%, and a false positive rate of 3.31% in defect detection. In addition, the comprehensive performance score of this detection model reached 96.99%. Moreover, it does not require the deployment of deep-learning models, has a low computing power cost, and is suitable for the detection requirements of large-scale mass production. Full article