Search Results (1,538)

Traditional Unmanned Aerial Vehicle (UAV) oblique photogrammetry for 3D real-scene modeling of historic cultural districts suffers from data gaps, insufficient texture, and poor accuracy in complex alleyway environments, hindering the widespread adoption of UAV technology. To address these challenges, this paper establishes a distortion region identification algorithm based on image grayscale variation range parameters. Then, through fusing UAV oblique photogrammetry, close-range smartphone photogrammetry, and Real-Time Kinematic (RTK) positioning technology, it ultimately constructs a 3D real-scene reconstruction technical framework. To validate the method’s effectiveness and reliability, a field experiment was conducted in the Zaoerxiang Historic Cultural District of Zhanggong District, Ganzhou City, Jiangxi Province, China. The experimental results demonstrate that the proposed algorithm can effectively identify distortions in the modeling results from UAV images. After fusing smartphone images from distorted regions and RTK measurements from ground control points (GCPs), the discrepancies in X, Y, and Z coordinates between the results and verification points mostly fall within 10 to 25 mm, while the differences from the measured lengths using a steel tape measure and a leveling rod were within the range of 10 to 20 mm. Furthermore, compared to approaches that rely solely on UAV images or on the fusion of UAV and all ground-based images for modeling, the method proposed in this paper restores building texture information in occluded areas and improves the accuracy of 3D real-scene modeling while simultaneously reducing data-processing and storage requirements and enhancing operational efficiency. It provides a referenceable technical framework for digital preservation, restoration planning, and smart cultural tourism of historic districts. Full article

Household livelihood resilience is an important foundation for sustainable rural development, particularly in rural areas exposed to climate risks, market fluctuations, and demographic pressures. This study examines whether participation in new rural collective economic organizations (NRCEOs) is associated with household livelihood resilience and explores the mechanisms and contextual heterogeneity underlying this association. Using survey data from 837 rural households in Jiangxi Province, China, we construct a multidimensional livelihood resilience index and apply ordinary least squares, propensity score matching, and lasso Regression, together with an exploratory IV-2SLS sensitivity analysis. The results show that participation in NRCEOs is positively associated with household livelihood resilience, and this relationship remains stable across alternative estimation strategies. Mechanism analysis provides evidence consistent with two pathways: land, labor, and capital allocation support the resource-allocation pathway, while production efficiency and agricultural income support the agricultural production pathway; the sales channel estimate remains inconclusive because online sales are rare in the sample and statistical power is limited. Overall, the findings indicate that the relationship between collective economic participation and household livelihood resilience varies across mechanism dimensions and local development contexts. Full article

Ning black autumn tea from Jiangxi, China, is often neglected by farmers due to quality decline under hot and arid autumn conditions. In this study, four soil moisture levels (T1–T4, ranging from 32.75% to 18.36%) were established through different sprinkler irrigation frequencies to investigate their effects on tea quality. T2 (27.98% soil moisture) exhibited the highest content of total free amino acids (13.77 mg/g), which was 13.33% higher than that in T4 (12.15 mg/g). Notably, T2 had the highest content of umami amino acids (6.75 mg/g) and the lowest content of bitter amino acids (3.07 mg/g) among all treatments. The total non-esterified catechin content in T2 (18.92 mg/g) was 2.74-fold higher than that in T4 (6.90 mg/g). Among the 55 volatile compounds identified, trans-nerolidol reached its highest odor activity value in T2 (11.77), contributing to a distinctive fruity and floral aroma. Sensory evaluation confirmed that T2 had the highest taste score (89.7), with significantly reduced bitterness and astringency, consistent with its enriched umami amino acids (6.75 mg/g) and lower bitter amino acids (3.07 mg/g). These findings demonstrate that maintaining soil moisture at approximately 28% through moderate sprinkler irrigation effectively balances flavor-related metabolites and improves autumn tea quality, offering a practical strategy to reduce resource waste and increase economic returns. Full article

This study developed a Photovoltaic–Reservoir Water Quality Impact Model (PVRWQIM) based on triangular fuzzy number theory (TFN) to address data sparsity and measurement uncertainty in conventional water quality assessment. The model consists of two components: a TFN-based exceedance-risk module for quantifying the likelihood of water quality parameters exceeding predefined risk thresholds, and a transitional TFN module for evaluating changes in exceedance risk before and after floating photovoltaic (FPV) construction. The model was applied to Junshan Reservoir in Jiangxi Province, China, using 15 observations each from before and after FPV construction. The results indicate the following: (i) Before construction, the exceedance probabilities for water temperature (T), dissolved oxygen (DO), permanganate index (COD_Mn), total phosphorus (TP), total nitrogen (TN), chlorophyll a (Chla), and cyanobacterial density (CD) were 16.7%, 16.1%, 31.3%, 33.7%, 33.3%, 32.7%, and 31.3%, respectively. After construction, the exceedance probabilities for T, DO, COD_Mn, TP, and TN increased to 93.1%, 89.7%, 82.5%, 83.5%, and 83.3%, respectively (p < 0.01), while the probabilities of exceedance for Chla and CD decreased to 14.8% and 14.2%, respectively (p < 0.05). (ii) T and DO are the primary threat factors triggered by FPV construction, with a probability of increased ecological risk of approximately 90%. (iii) The model reveals a statistical correlation pattern: the probability of reduced ecological risk for CD and Chla is 62%, while the probability of increased ecological risk for COD_Mn, TP, and TN is 77%. The two sets of indicators exhibit opposite trends, suggesting that FPV shading may directly suppress algae growth while simultaneously weakening self-purification capacity indirectly through cooling and reduced water flow, thereby contributing to nutrient accumulation. It should be noted that, based on limited observational data, this study reveals correlations rather than proven causal mechanisms; the aforementioned causal interpretations require further validation through controlled experiments or mechanistic models in the future. (iv) The proposed PVRWQIM provides a practical tool for quantifying reservoir water quality risks under sparse data and measurement uncertainty and can support environmental assessment of similar FPV projects. Full article

Early weaning can disrupt the intestinal function and microbial community balance of piglets, and trigger inflammation and oxidative stress, thereby affecting their production performance. In recent years, butyric acid has gained considerable interest as a functional feed additive. However, practical limitations such as its pungent odor and low absorption efficiency in the digestive tract have led to the development of more stable forms, including sodium butyrate, coated butyrate, and butyrate glycerides, etc. Research has shown that butyric acid and its derivatives can serve as effective feed additives by enhancing pigs’ resistance to pathogenic colonization, stabilizing the intestinal microbiota, and alleviating oxidative stress to mitigate challenges such as weaning stress and pathogenic infections. This review systematically highlights the role of butyric acid and its derivatives as dietary supplements for weaned piglets. Importantly, it underscores the potential of butyric acid and its derivatives may contribute to antibiotic-reduction strategies in weaned piglet nutrition, while also highlighting the need for optimized supplementation strategies and further investigation into synergistic effects with other feed additives. This review aims to offer both theoretical and practical insights for the application of butyric acid in weaned piglet nutrition. Full article

Traditional research was mostly focused on the effects of emulsions on the mechanical properties and durability of cement mortar, while studies on the regulation mechanism of emulsions on the rheological properties of cement-based materials and the coupling mechanism with the hydration process were rarely conducted. In this paper, a novel core–shell structured emulsion was prepared by free radical polymerization. The regulation of cement mortar yield stress, creep recovery, dynamic viscosity, and thixotropy by different dosages (0–10%) of the emulsion admixture was systematically investigated, and combined with characterization by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR), the microscopic action mechanism of the emulsion was elucidated. It was demonstrated that the Bingham fluid behavior of cement mortar was not altered by the core–shell emulsion, whereas a significant dosage-dependent regulatory effect on its rheological parameters was observed, and a critical regulation interval of 4–6% was identified. At an emulsion dosage of 10%, the yield stress of the mortar was increased by 937.0% compared to that of the control group. At dosages of 2–4%, the static structural stability and construction flowability of the mortar were synergistically optimized, and the weakest thixotropy and the best structural stability were exhibited at an emulsion dosage of 4%. A more pronounced shear-thinning behavior was shown by all modified mortars, and their high-shear flowability was not affected. Microstructural analysis confirmed that no chemical reaction occurred between the emulsion and the cement hydration products. Through the triple effects of “hydration retardation by physical coating, pore filling and densification, and composite network enhancement”, a film was formed on the surface of cement particles by the emulsion, which hindered the diffusion of water and ions, thereby regulating the cement hydration process and microstructural evolution. Full article

Rice–crayfish co-culture is a dominant aquaculture mode in China, while the regional heterogeneity in crayfish nutritional quality remains insufficiently clarified. This study collected rice-field-cultured crayfish samples from six major producing provinces (Henan, Hubei, Hunan, Jiangxi, Jiangsu, and Anhui) to systematically evaluate their meat yield, conventional nutritional components, amino acid and fatty acid profiles, and mineral element contents. Significant regional differences were observed in all measured indicators. Jiangsu crayfish showed the highest meat yield (22.97% in females, 20.72% in males), crude protein (18.5%), and total amino acids (16.59 g/100 g). Jiangxi samples had the highest crude fat (0.7%), ash (1.5%), and calcium (1280 mg/kg). Anhui crayfish exhibited the highest polyunsaturated fatty acid (PUFA) content (47.30%). Hubei recorded the highest total eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) (22.41%). Henan crayfish were highest in EPA (19.6%) and manganese (3.72 mg/kg), while Hunan samples had the highest iron (9.06 mg/kg). Valine was identified as the first limiting amino acid in all provinces, with secondary limiting amino acids varying regionally. Despite regional differences in specific nutritional indices, crayfish from all six provinces consistently exhibited high protein, low fat, balanced amino acid profiles, abundant unsaturated fatty acids, and rich essential minerals, with all measured nutritional mineral contents within national food safety limits. The findings provided empirical data and a scientific basis for crayfish quality evaluation, origin characteristic analysis, and targeted nutritional optimization of farming formulas, as well as for the differentiated development of regional crayfish industries. Full article

Traditional mineral drugs represent an underexploited reservoir of natural antitumor agents; however, their clinical translation has historically been hindered by poor bioavailability, non-specific biodistribution, and dose-limiting toxicity. This review comprehensively examines the pharmacological mechanisms and modern formulation strategies driving the renaissance of mineral-based oncology therapeutics. We highlight how mineral drugs exert potent anticancer effects through interconnected pathways, including regulated cell death (e.g., apoptosis, ferroptosis), cell-cycle arrest, and immunomodulation. Crucially, we evaluate recent advances in drug delivery systems, such as liposomes, polymeric nanoparticles, inorganic frameworks, and stimuli-responsive (e.g., pH, redox, enzyme) release systems that successfully overcome traditional pharmacological barriers. These bioengineering strategies not only improve solubility and tumor targeting but also significantly widen the therapeutic window, as evidenced by enhanced tumor suppression and reduced systemic toxicity in preclinical models. Despite this progress, challenges regarding in vivo chemical transformations and tumor heterogeneity remain. Ultimately, we propose a closed-loop “Composition–Mechanism–Delivery” design paradigm to guide future research, facilitating the translation of ethnopharmacological heritage into precision mineral-based therapeutics. Full article

Under global warming, understanding regional drought evolution is essential for drought early warning, food security, climate adaptation, and sustainable water-resource management. This study analyzed meteorological drought in Jiangxi Province during 1961–2022 using SPI-12, SPEI-12, and EDDI-12 from the CHM_Drought high-resolution multi-index dataset. The Mann–Kendall (MK) test, Theil–Sen slope estimator, three-threshold run theory, Morlet wavelet analysis, wavelet coherence (WTC), and cross-wavelet transform (XWT) were used to examine drought trends, event characteristics, periodicity, and inter-index relationships. Results showed a widespread drying tendency. EDDI-12 exhibited a highly significant increase in 99.86% of valid resampled raster pixels, indicating enhanced atmospheric evaporative demand, while SPEI-12 and SPI-12 showed significant decreasing trends in 97.96% and 93.24% of valid pixels, respectively. Stronger drying signals were mainly distributed in central and northern Jiangxi. Run-theory analysis indicated longer-duration cumulative droughts in southern mountainous areas and frequent short-duration drought events in the Poyang Lake Plain and central-northern Jiangxi. Wavelet analysis identified a dominant interdecadal periodicity of approximately 20–21 years. WTC and XWT revealed strong in-phase coherence between SPI and SPEI, whereas SPI/SPEI and EDDI mainly showed anti-phase statistical phase relationships. From a sustainability perspective, these findings provide scientific support for multi-index drought monitoring, adaptive agricultural water allocation, drought early warning, and climate-resilient water-resource management in humid monsoon regions. Full article

Life satisfaction (LS) is an important indicator of subjective well-being among college students. However, relatively few studies have integrated variable-centered and person-centered approaches to examine the associations among physical activity (PA), social support (SS), and LS in female college students. This cross-sectional study surveyed 2097 female college students from 11 universities in Jiangxi Province, China. PA, SS, and LS were assessed using self-report questionnaires. A mediation model was used to examine whether SS statistically mediated the association between PA and LS after controlling for education level and place of origin. Latent profile analysis was then conducted using six LS items, and the BCH method was used to compare PA and SS across profiles. The results showed that PA was positively associated with SS and LS, and SS was positively associated with LS. The indirect association between PA and LS through SS was statistically significant, suggesting a partial statistical mediation pattern. Latent profile analysis identified three level-based LS profiles: low-, medium-, and high-LS profiles. PA and SS increased progressively across these profiles, with the highest levels in the high-LS profile and the lowest levels in the low-LS profile. These findings suggest that PA, SS, and LS are closely interrelated and that meaningful quantitative heterogeneity exists in LS among female college students. Given the cross-sectional design and convenience sampling, the findings should be interpreted as statistical associations rather than causal effects. Full article

The Huomaxie granite in Ningdu, southern Jiangxi Province, is located in the central part of the Cathaysia Block. Previous studies assigned this pluton to the Huitong batholith as S-type granite, but lacked precise geochronological and petrogenetic constraints. This paper presents systematic petrography, whole-rock geochemistry, zircon U–Pb dating, in situ Hf isotopic analysis, and electron microprobe analysis (EPMA) of muscovite from the muscovite monzogranite of the pluton. The weighted mean ²⁰⁶Pb/²³⁸U age is 420.1 ± 3.1 Ma. The rocks are silicic, high-K calc-alkaline, and peraluminous S-type granites. Zircon ε_Hf(t) values range from −15.0 to −11.8, with two-stage Hf model ages (T_DM2) of 2360–2150 Ma. Geochemical characteristics and muscovite composition data indicate that the magma was derived from high-temperature partial melting of psammitic sedimentary rocks. Tectonic discrimination diagrams suggest that the pluton formed in a post-orogenic extensional setting. It was generated by lower crustal melting induced by asthenospheric upwelling. Full article

Improving detection performance across diverse synthetic aperture radar (SAR) scenes remains challenging because different datasets exhibit different levels of target–background separability. To address this issue, we propose a constant false alarm rate (CFAR)-guided mode-selective network (CGMSN), which selects an appropriate feature-fusion mode according to the CFAR target–background separation margin. Specifically, CFAR is used as an interpretable statistical tool to construct an anomaly response map. The separation margin is then calculated by comparing the average CFAR anomaly responses of annotated target regions and their surrounding contextual backgrounds. Based on this indicator, a You Only Look Once version 8 (YOLOv8)-based mode-selective detector is constructed with three key components. First, a lightweight representation-enhanced backbone that integrates ResNet18 and a dilated convolutional spatial pyramid (DCSP) module is adopted to improve contextual representation while maintaining moderate model complexity. Second, a mode-selective neck (MSN) is designed with three predefined fusion modes, where the appropriate fusion depth is selected according to the CFAR-guided target–background separation margin of each dataset. Third, a complete intersection over the union modulated head (CMH) is developed to enhance classification-regression alignment and suppress clutter-induced responses. Experiments on SAR-Aircraft-1.0, High-Resolution SAR Images Dataset (HRSID), and SAR Ship Detection Dataset (SSDD) indicate that datasets with smaller CFAR target–background separation margins benefit from deeper fusion, while datasets with larger separation margins can adopt shallower fusion. Moreover, the proposed CGMSN achieves superior performance over representative detectors, demonstrating its effectiveness on the evaluated SAR datasets with diverse scene characteristics. Full article

Auxin response factors (ARFs) are pivotal regulators mediating plant growth, development, and abiotic stress responses, especially during seed germination under stressful conditions. However, the ARF gene family has not been thoroughly studied or characterized in sesame. The identification and characterization of ARF family members in the sesame genome were analyzed by bioinformatics methods, and the expression patterns of sesame ARF genes were assessed by quantitative real-time PCR. In this study, a total of 23 ARF genes were identified in the sesame genome, distributed unevenly across 12 chromosomes. Additionally, 15 segmental duplication events were detected. Phylogenetic analysis classified the SiARF genes into four subfamilies, with members within each subgroup sharing conserved structural features and motif compositions. Promoter analysis revealed multiple cis-acting elements associated with plant growth, phytohormone responses, and stress responses. Expression profiling demonstrated distinct tissue-specific expression patterns among the SiARF genes. Notably, SiARF5 and SiARF15 showed predominant expression in seeds 5 days after pollination, whereas SiARF14 exhibited broad expression in roots, stems, leaves, and seeds germinated for 24 h. QRT-PCR analysis identified eight SiARF genes exhibiting biphasic expression patterns during seed germination under abiotic stresses, characterized by initial downregulation and subsequent upregulation. Among them, SiARF11 showed significant induction under all three stress conditions, while SiARF9 was specifically upregulated under salt stress, suggesting their critical roles in stress response regulation. These findings provide a foundation for further investigation into Auxin-mediated responses to abiotic stress during seed germination in sesame. Full article

In smallholder-dominated agricultural systems, farm expansion is often expected to improve agricultural performance, yet a larger operated area does not necessarily translate into higher returns per unit of land. This issue is particularly relevant in rice farming, where land fragmentation, labor constraints, and uneven access to agricultural services may limit the return-enhancing effect of farm-scale management (FSM). Using 2024 household survey data from 732 rice-farming households in Jiangxi Province, China, this study examines how FSM, service-scale management (SSM), and their organizational matching affect rice-farming returns (RFR). We apply ordinary least squares (OLS) regression models with interaction-term specifications and further conduct mechanism, moderation, and heterogeneity analyses. The results show that FSM alone does not automatically increase per-mu net operating returns, whereas SSM is positively associated with RFR. More importantly, the interaction between FSM and SSM is significantly positive, indicating that farm expansion generates return advantages mainly when supported by agricultural socialized services. Mechanism analysis suggests that this synergistic effect operates partly through higher land consolidation (LC) and more formalized service contractualization (SC), while smart agricultural technology (SAT) further strengthens the return-enhancing effect. Heterogeneity analysis further shows that the effect differs across farmers with different operating scales. These findings suggest that smallholder modernization should not be understood as land expansion alone but as the organizational matching between farm scale and the service-based division of labor. Policy efforts should therefore aim to improve agricultural socialized service systems, promote land consolidation, strengthen service contracts, and integrate smart agricultural technologies into service provision. Full article

The thiourea grafting method can effectively improve the ability of activated carbon to recover chloroauric acid (AuCl₄⁻). Conventional grafting strategies rely on acyl halide reactions using reagents such as SOCl₂ and CH₂Cl₂, which suffer from instability and high toxicity. Herein, we propose a green grafting strategy for thiourea by activating carboxyl groups with EDC-HCl/NHS in acetonitrile, followed by the amidation reaction to obtain thiourea-modified carbon (AC-NCS). FT-IR and XPS analyses confirm the successful grafting of thiourea onto the activated carbon surface. Compared with pristine activated carbon, the adsorption capacity of AC-NCS is 104.8 mg/g, increased by 5.76 times. Furthermore, it maintains a recovery rate of 84.2% after three cycles. XPS and FT-IR further reveal that adsorption occurs on the thiourea sulfur atoms (C=S) and protonated primary amines(-NH₃⁺), and the recovery of chloroauric acid is achieved through a synergistic “reduction–electrostatic attraction” mechanism. This method reduces the dependence on highly toxic reagents and provides a promising approach for the efficient and green recovery of gold from secondary resources. Full article